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Clara Guerra-Duarte
Laboratorio Central de Saude Publica, Fundacao Ezequiel Dias, Belo Horizonte, Brazil

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Journal article
Published: 20 June 2020 in International Journal of Biological Macromolecules
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Loxoscelism pose a health issue in the South America. The treatment for these accidents is based on the administration of antivenom produced in animals immunized with Loxosceles venom. In this work, a previously produced non-toxic multiepitopic chimeric protein (rMEPlox), composed of epitopes derived from the main toxins families (sphyngomielinase-D, metalloproteases, and hyaluronidases) of Loxosceles spider venoms, was used as antigen to produce monoclonal antibodies (mAbs). A selected anti-rMEPlox mAb (Lox-mAb3) reacted with metalloprotease from L. intermedia venom and showed cross-reactivity with metalloproteses from Brazilian and Peruvian Loxosceles laeta and Loxosceles gaucho venoms in immunoassays. The sequence recognized by Lox-mAb3 (184ENNTRTIGPFDYDSIMLYGAY205) corresponds to the C-terminal region of Astacin-like metalloprotease 1 and the amino acid sequence IGPFDYDSI, conserved among the homologs metalloproteases sequences, is important for antibody recognition. Lox-mAb3 neutralizes the fibrinogenolytic activity caused by metalloprotease from L. intermedia spider venom in vitro, which may lead to a decrease in hemorrhagic disturbances caused by Loxosceles envenomation. Our results show, for the first time, the use of a non-toxic multiepitopic protein for the production of a neutralizing monoclonal antibody against a metalloprotease of medically important Loxosceles venoms. These results contribute for the production improvement of therapeutic antivenom against loxoscelism.

ACS Style

Tamara G.F. Costa; Fernanda Costal-Oliveira; Thamyres C.S. de Assis; Sabrina A. Lima; Christina A. Martins; Alessandra B. Finco; Sílvio S. Veiga; Vanete T. Soccol; Ricardo A. Machado-De-Ávila; Luís F.M. Figueiredo; João C. Minozzo; Evanguedes Kalapothakis; Clara Guerra-Duarte; Larissa M. Alvarenga; Carlos Chávez-Olórtegui. Engineered antigen containing epitopes from Loxosceles spp. spider toxins induces a monoclonal antibody (Lox-mAb3) against astacin-like metalloproteases. International Journal of Biological Macromolecules 2020, 162, 490 -500.

AMA Style

Tamara G.F. Costa, Fernanda Costal-Oliveira, Thamyres C.S. de Assis, Sabrina A. Lima, Christina A. Martins, Alessandra B. Finco, Sílvio S. Veiga, Vanete T. Soccol, Ricardo A. Machado-De-Ávila, Luís F.M. Figueiredo, João C. Minozzo, Evanguedes Kalapothakis, Clara Guerra-Duarte, Larissa M. Alvarenga, Carlos Chávez-Olórtegui. Engineered antigen containing epitopes from Loxosceles spp. spider toxins induces a monoclonal antibody (Lox-mAb3) against astacin-like metalloproteases. International Journal of Biological Macromolecules. 2020; 162 ():490-500.

Chicago/Turabian Style

Tamara G.F. Costa; Fernanda Costal-Oliveira; Thamyres C.S. de Assis; Sabrina A. Lima; Christina A. Martins; Alessandra B. Finco; Sílvio S. Veiga; Vanete T. Soccol; Ricardo A. Machado-De-Ávila; Luís F.M. Figueiredo; João C. Minozzo; Evanguedes Kalapothakis; Clara Guerra-Duarte; Larissa M. Alvarenga; Carlos Chávez-Olórtegui. 2020. "Engineered antigen containing epitopes from Loxosceles spp. spider toxins induces a monoclonal antibody (Lox-mAb3) against astacin-like metalloproteases." International Journal of Biological Macromolecules 162, no. : 490-500.

Journal article
Published: 29 May 2020 in Toxicon
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Bothrops brazili is a pitviper from Amazonian region, responsible for many accidents in Peru. Despite its relevance, its venom has not been extensively characterized. In the present work, Bothrops brazili venom (BbV) components were analyzed by RP-HPLC, SDS-PAGE and MALDI-TOF/TOF. Approximately 37 proteins were identified, belonging to 7 families. Snake venom metalloproteinases (SVMPs) were the most abundant proteins of the venom (33.05%), followed by snake venom serine proteinases (SVSPs, 26.11%), phospholipases A2 (PLA2, 25.57%), snake C-type lectins (CTLs, 9.61%), L-aminoacid oxidase (LAAO, 3.80%), cystein-rich secretory proteins (CRISP, 1.67%) and Bradykinin-potentiating peptide (BPP, 0.20%). In vitro enzymatic activities of BbV showed high levels of SVMP activity and reduced Hyal activity in comparison with other bothropic venoms. Furthermore, BbV reduced VERO cells viability. ELISA and Western Blotting showed that both Peruvian and Brazilian bothropic antivenoms were able to recognize BbV components. This work provides an overview of BbV venom content and indicates a potential efficiency of Peruvian and Brazilian antivenoms to treat accidents with this species.

ACS Style

Carolina Rego Rodrigues; Denis Alexis Molina Molina; Thamyres C. Silva de Assis; Camila Liberato; Marcella N. Melo-Braga; César Bonilla Ferreyra; Javier Cárdenas; Fernanda Costal-Oliveira; Clara Guerra-Duarte; Carlos Chávez-Olórtegui. Proteomic and toxinological characterization of Peruvian pitviper Bothrops brazili (“jergón shushupe”), venom. Toxicon 2020, 184, 19 -27.

AMA Style

Carolina Rego Rodrigues, Denis Alexis Molina Molina, Thamyres C. Silva de Assis, Camila Liberato, Marcella N. Melo-Braga, César Bonilla Ferreyra, Javier Cárdenas, Fernanda Costal-Oliveira, Clara Guerra-Duarte, Carlos Chávez-Olórtegui. Proteomic and toxinological characterization of Peruvian pitviper Bothrops brazili (“jergón shushupe”), venom. Toxicon. 2020; 184 ():19-27.

Chicago/Turabian Style

Carolina Rego Rodrigues; Denis Alexis Molina Molina; Thamyres C. Silva de Assis; Camila Liberato; Marcella N. Melo-Braga; César Bonilla Ferreyra; Javier Cárdenas; Fernanda Costal-Oliveira; Clara Guerra-Duarte; Carlos Chávez-Olórtegui. 2020. "Proteomic and toxinological characterization of Peruvian pitviper Bothrops brazili (“jergón shushupe”), venom." Toxicon 184, no. : 19-27.

Journal article
Published: 25 May 2020 in International Journal of Biological Macromolecules
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Snakebites caused by Crotalus genus are the second most frequent in Brazil. Crotoxin is a beta-neurotoxin responsible for the main envenomation effects of Crotalus biting, while crotamine immobilizes the animal hind limbs, contributing to prey immobilization and to envenoming symptoms. As crotoxin and crotamine represent about 90% of Crotalus venom dry weight, these toxins are of great importance for antivenom therapy. In this sense, knowledge regarding the antigenicity/immunogenicity at the molecular level of these toxins can provide valuable information for the improvement of specific antivenoms. Therefore, the aims of this study are the identification of the B-cell epitopes from crotoxin and crotamine; and the characterization of the neutralizing potency of antibodies directed against the corresponding synthetic epitopes defined in the current study. Linear B-cell epitopes were identified using the Spot Synthesis technique probed with specific anti-C. d. terrificus venom horse IgG. One epitope of crotamine (F12PKEKICLPPSSDFGKMDCRW32) and three of crotoxin (L10LVGVEGHLLQFNKMIKFETR30; Y43CGWGGRGRPKDATDRCCFVH63 and T118YKYGYMFYPDSRCRGPSETC138) were identified. After synthesis in their soluble form, the peptides mixture correspondent to the mapped epitopes was entrapped in liposomes and used as immunogens for antibody production in rabbits. Anti-synthetic peptide antibodies were able to protect mice from the lethal activity of C. d. terrificus venom.

ACS Style

Patrícia D. Vaz de Melo; Sabrina De Almeida Lima; Priscila Araújo; Raíssa Medina Santos; Edgar Gonzalez; Andreza Alves Belo; Ricardo Andrez Machado de Ávila; Fernanda Costal-Oliveira; Vanete Thomaz Soccol; Clara Guerra-Duarte; Leonides Rezende; Carlos Chavez-Olortegui. Immunoprotection against lethal effects of Crotalus durissus snake venom elicited by synthetic epitopes trapped in liposomes. International Journal of Biological Macromolecules 2020, 161, 299 -307.

AMA Style

Patrícia D. Vaz de Melo, Sabrina De Almeida Lima, Priscila Araújo, Raíssa Medina Santos, Edgar Gonzalez, Andreza Alves Belo, Ricardo Andrez Machado de Ávila, Fernanda Costal-Oliveira, Vanete Thomaz Soccol, Clara Guerra-Duarte, Leonides Rezende, Carlos Chavez-Olortegui. Immunoprotection against lethal effects of Crotalus durissus snake venom elicited by synthetic epitopes trapped in liposomes. International Journal of Biological Macromolecules. 2020; 161 ():299-307.

Chicago/Turabian Style

Patrícia D. Vaz de Melo; Sabrina De Almeida Lima; Priscila Araújo; Raíssa Medina Santos; Edgar Gonzalez; Andreza Alves Belo; Ricardo Andrez Machado de Ávila; Fernanda Costal-Oliveira; Vanete Thomaz Soccol; Clara Guerra-Duarte; Leonides Rezende; Carlos Chavez-Olortegui. 2020. "Immunoprotection against lethal effects of Crotalus durissus snake venom elicited by synthetic epitopes trapped in liposomes." International Journal of Biological Macromolecules 161, no. : 299-307.

Other
Published: 11 May 2020
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The recent emergence of a previously unknown coronavirus (SARS-CoV-2), first confirmed in the city of Wuhan in China in December 2019, has caused serious public health and economic issues due to its rapid dissemination worldwide. Although 61,888 confirmed cases had been reported in Brazil by 28 April 2020, little was known about the SARS-CoV-2 epidemic in the country. To better understand the recent epidemic in the second most populous state in southeast Brazil (Minas Gerais, MG), we looked at existing epidemiological data from 3 states and sequenced 40 complete genomes from MG cases using Nanopore. We found evidence of multiple independent introductions from outside MG, both from genome analyses and the overly dispersed distribution of reported cases and deaths. Epidemiological estimates of the reproductive number using different data sources and theoretical assumptions all suggest a reduction in transmission potential since the first reported case, but potential for sustained transmission in the near future. The estimated date of introduction in Brazil was consistent with epidemiological data from the first case of a returning-traveler from Lombardy, Italy. These findings highlight the unique reality of MG’s epidemic and reinforce the need for real-time and continued genomic surveillance strategies as a way of understanding and therefore preparing against the epidemic spread of emerging viral pathogens.

ACS Style

Joilson Xavier; Marta Giovanetti; Talita Adelino; Vagner Fonseca; Alana Vitor Barbosa da Costa; Adriana Aparecida Ribeiro; Katlin Nascimento Felicio; Clara Guerra Duarte; Marcos Vinicius Ferreira Silva; Álvaro Salgado; Mauricio Teixeira Lima; Ronaldo de Jesus; Allison Fabri; Cristiane Franco Soares Zoboli; Thales Gutemberg Souza Santos; Felipe Iani; Ana Maria Bispo de Filippis; Marilda Agudo Mendonça Teixeira de Siqueira; André Luiz de Abreu; Vasco de Azevedo; Dario Brock Ramalho; Carlos F. Campelo de Albuquerque; Tulio de Oliveira; Edward C. Holmes; José Lourenço; Luiz Carlos Junior Alcantara; Marluce Aparecida Assunção Oliveira. The ongoing COVID-19 epidemic in Minas Gerais, Brazil: insights from epidemiological data and SARS-CoV-2 whole genome sequencing. 2020, 1 .

AMA Style

Joilson Xavier, Marta Giovanetti, Talita Adelino, Vagner Fonseca, Alana Vitor Barbosa da Costa, Adriana Aparecida Ribeiro, Katlin Nascimento Felicio, Clara Guerra Duarte, Marcos Vinicius Ferreira Silva, Álvaro Salgado, Mauricio Teixeira Lima, Ronaldo de Jesus, Allison Fabri, Cristiane Franco Soares Zoboli, Thales Gutemberg Souza Santos, Felipe Iani, Ana Maria Bispo de Filippis, Marilda Agudo Mendonça Teixeira de Siqueira, André Luiz de Abreu, Vasco de Azevedo, Dario Brock Ramalho, Carlos F. Campelo de Albuquerque, Tulio de Oliveira, Edward C. Holmes, José Lourenço, Luiz Carlos Junior Alcantara, Marluce Aparecida Assunção Oliveira. The ongoing COVID-19 epidemic in Minas Gerais, Brazil: insights from epidemiological data and SARS-CoV-2 whole genome sequencing. . 2020; ():1.

Chicago/Turabian Style

Joilson Xavier; Marta Giovanetti; Talita Adelino; Vagner Fonseca; Alana Vitor Barbosa da Costa; Adriana Aparecida Ribeiro; Katlin Nascimento Felicio; Clara Guerra Duarte; Marcos Vinicius Ferreira Silva; Álvaro Salgado; Mauricio Teixeira Lima; Ronaldo de Jesus; Allison Fabri; Cristiane Franco Soares Zoboli; Thales Gutemberg Souza Santos; Felipe Iani; Ana Maria Bispo de Filippis; Marilda Agudo Mendonça Teixeira de Siqueira; André Luiz de Abreu; Vasco de Azevedo; Dario Brock Ramalho; Carlos F. Campelo de Albuquerque; Tulio de Oliveira; Edward C. Holmes; José Lourenço; Luiz Carlos Junior Alcantara; Marluce Aparecida Assunção Oliveira. 2020. "The ongoing COVID-19 epidemic in Minas Gerais, Brazil: insights from epidemiological data and SARS-CoV-2 whole genome sequencing." , no. : 1.

Journal article
Published: 02 February 2020 in Molecular Immunology
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Crotoxin (Ctx) is the main lethal component of Crotalus durissus terrificus venom. It is a neurotoxin, composed of two subunits associated by noncovalent interactions, the non-toxic acid subunit (CA), named Crotapotin, and the basic subunit (CB), with phospholipase A2 (PLA2) activity. Employing the SPOT synthesis technique, we determined two epitopes located in the C-terminal of each Ctx subunit. In addition, 3 other epitopes were mapped in different regions of Ctx using subcutaneous spot implants surgically inserted in mice. All epitopes mapped here were expressed together as recombinant multi-epitopic protein (rMEPCtx), which was used to immunize New Zealand rabbits. Anti-rMEPCtx rabbit serum cross-reacted with Ctx and crude venoms from C. d. terrificus, Crotalus durissus ruruima, Peruvian C. durissus and Bothrops jararaca (with lower intensity). Furthermore, anti-rMEPCtx serum was able to neutralize Ctx lethal activity. As the recombinant multiepitopic protein is not toxic, it can be administered in larger doses without causing adverse effects on the immunized animals health. Therefore, our work evidences the identification of neutralizing epitopes of Ctx and support the use of recombinant multiepitopic proteins as an innovation to immunotherapeutics production.

ACS Style

Denis A. Molina Molina; Clara Guerra-Duarte; Fernanda Costal-Oliveira; Elizângela Almeida Rocha; Carolina Rego Rodrigues; Ricardo Andrez Machado de Ávila; Vanete Thomaz Soccol; Carlos Chávez-Olórtegui. Engineered protein containing crotoxin epitopes induces neutralizing antibodies in immunized rabbits. Molecular Immunology 2020, 119, 144 -153.

AMA Style

Denis A. Molina Molina, Clara Guerra-Duarte, Fernanda Costal-Oliveira, Elizângela Almeida Rocha, Carolina Rego Rodrigues, Ricardo Andrez Machado de Ávila, Vanete Thomaz Soccol, Carlos Chávez-Olórtegui. Engineered protein containing crotoxin epitopes induces neutralizing antibodies in immunized rabbits. Molecular Immunology. 2020; 119 ():144-153.

Chicago/Turabian Style

Denis A. Molina Molina; Clara Guerra-Duarte; Fernanda Costal-Oliveira; Elizângela Almeida Rocha; Carolina Rego Rodrigues; Ricardo Andrez Machado de Ávila; Vanete Thomaz Soccol; Carlos Chávez-Olórtegui. 2020. "Engineered protein containing crotoxin epitopes induces neutralizing antibodies in immunized rabbits." Molecular Immunology 119, no. : 144-153.

Articles
Published: 01 January 2020 in Emerging Microbes & Infections
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The recent emergence of a previously unknown coronavirus (SARS-CoV-2), first identified in the Chinese city of Wuhan in December 2019, has had major public health and economic consequences. Although 61,888 confirmed cases were reported in Brazil by 28 April 2020, little is known about the SARS-CoV-2 epidemic in this country. To better understand the recent epidemic in the second most populous state in southeast Brazil - Minas Gerais (MG) - we sequenced 40 complete SARS-CoV-2 genomes from MG cases and examined epidemiological data from three Brazilian states. Both the genome analyses and the geographical distribution of reported cases provided evidence for multiple independent introductions into MG. Epidemiological estimates of the reproductive number (R) using different data sources and theoretical assumptions suggest the potential for sustained virus transmission despite a reduction in R from the first reported case to the end of April 2020. The estimated date of SARS-CoV-2 introduction into Brazil was consistent with epidemiological data from the first case of a returned traveller from Lombardy, Italy. These findings highlight the nature of the COVID-19 epidemic in MG and reinforce the need for real-time and continued genomic surveillance strategies to better understand and prepare for the epidemic spread of emerging viral pathogens.

ACS Style

Joilson Xavier; Marta Giovanetti; Talita Adelino; Vagner Fonseca; Alana Vitor Barbosa Da Costa Bsc; Adriana Aparecida Ribeiro Bsc; Katlin Nascimento Felicio; Clara Guerra Duarte; Marcos Vinicius Ferreira Silva; Álvaro Salgado; Mauricio Teixeira Lima; Ronaldo de Jesus; Allison Fabri; Cristiane Franco Soares Zoboli Bsc; Thales Gutemberg Souza Santos; Felipe Iani; Massimo Ciccozzi; Ana Maria Bispo de Filippis; Marilda Agudo Mendonça Teixeira de Siqueira; André Luiz De Abreu Msc; Vasco de Azevedo; Dario Brock Ramalho Bsc; Carlos F. Campelo De Albuquerque Msc; Tulio de Oliveira; Edward C. Holmes; José Lourenço; Luiz Carlos Junior Alcantara; Marluce Aparecida Assunção Oliveira. The ongoing COVID-19 epidemic in Minas Gerais, Brazil: insights from epidemiological data and SARS-CoV-2 whole genome sequencing. Emerging Microbes & Infections 2020, 9, 1824 -1834.

AMA Style

Joilson Xavier, Marta Giovanetti, Talita Adelino, Vagner Fonseca, Alana Vitor Barbosa Da Costa Bsc, Adriana Aparecida Ribeiro Bsc, Katlin Nascimento Felicio, Clara Guerra Duarte, Marcos Vinicius Ferreira Silva, Álvaro Salgado, Mauricio Teixeira Lima, Ronaldo de Jesus, Allison Fabri, Cristiane Franco Soares Zoboli Bsc, Thales Gutemberg Souza Santos, Felipe Iani, Massimo Ciccozzi, Ana Maria Bispo de Filippis, Marilda Agudo Mendonça Teixeira de Siqueira, André Luiz De Abreu Msc, Vasco de Azevedo, Dario Brock Ramalho Bsc, Carlos F. Campelo De Albuquerque Msc, Tulio de Oliveira, Edward C. Holmes, José Lourenço, Luiz Carlos Junior Alcantara, Marluce Aparecida Assunção Oliveira. The ongoing COVID-19 epidemic in Minas Gerais, Brazil: insights from epidemiological data and SARS-CoV-2 whole genome sequencing. Emerging Microbes & Infections. 2020; 9 (1):1824-1834.

Chicago/Turabian Style

Joilson Xavier; Marta Giovanetti; Talita Adelino; Vagner Fonseca; Alana Vitor Barbosa Da Costa Bsc; Adriana Aparecida Ribeiro Bsc; Katlin Nascimento Felicio; Clara Guerra Duarte; Marcos Vinicius Ferreira Silva; Álvaro Salgado; Mauricio Teixeira Lima; Ronaldo de Jesus; Allison Fabri; Cristiane Franco Soares Zoboli Bsc; Thales Gutemberg Souza Santos; Felipe Iani; Massimo Ciccozzi; Ana Maria Bispo de Filippis; Marilda Agudo Mendonça Teixeira de Siqueira; André Luiz De Abreu Msc; Vasco de Azevedo; Dario Brock Ramalho Bsc; Carlos F. Campelo De Albuquerque Msc; Tulio de Oliveira; Edward C. Holmes; José Lourenço; Luiz Carlos Junior Alcantara; Marluce Aparecida Assunção Oliveira. 2020. "The ongoing COVID-19 epidemic in Minas Gerais, Brazil: insights from epidemiological data and SARS-CoV-2 whole genome sequencing." Emerging Microbes & Infections 9, no. 1: 1824-1834.

Short communication
Published: 01 January 2020 in Journal of Venomous Animals and Toxins including Tropical Diseases
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ACS Style

Ana Luiza Bittencourt Paiva; Alessandra Matavel; Bruno César Souza Silva; Clara Guerra-Duarte; Marcelo Ribeiro Vasconcelos Diniz. Gene sequence analysis of toxins from the spider Phoneutria nigriventer revealed an intronless feature. Journal of Venomous Animals and Toxins including Tropical Diseases 2020, 26, 1 .

AMA Style

Ana Luiza Bittencourt Paiva, Alessandra Matavel, Bruno César Souza Silva, Clara Guerra-Duarte, Marcelo Ribeiro Vasconcelos Diniz. Gene sequence analysis of toxins from the spider Phoneutria nigriventer revealed an intronless feature. Journal of Venomous Animals and Toxins including Tropical Diseases. 2020; 26 ():1.

Chicago/Turabian Style

Ana Luiza Bittencourt Paiva; Alessandra Matavel; Bruno César Souza Silva; Clara Guerra-Duarte; Marcelo Ribeiro Vasconcelos Diniz. 2020. "Gene sequence analysis of toxins from the spider Phoneutria nigriventer revealed an intronless feature." Journal of Venomous Animals and Toxins including Tropical Diseases 26, no. : 1.

Review article
Published: 11 November 2019 in Toxicon
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Loxosceles spp. (Araneae, Sicariidae), known as brown spiders, are distributed in temperate and tropical regions worldwide. Accidents caused by these spiders are known as loxoscelism and constitute a public health problem, especially in Brazil. The present review describes the taxonomy, distribution, and ecological profile of brown spiders, as well as the molecular and biochemical aspects of Loxosceles venom. Additionally, it presents an overview on L. similis, a species found in the Southeastern region of Brazil. In this region, the number of Loxosceles accidents has been increasing in the past few years, thus calling attention to its raising importance as a medically relevant spider species in Brazil.

ACS Style

Bárbara Bruna Ribeiro de Oliveira-Mendes; Maria Chatzaki; Douglas Ferreira Sales-Medina; Hortênsia Gomes Leal; Ray van der Veer; Gabriela Lago Biscoto; Priscila Mendes Gonçalves; Thais Soares da Silva; Clara Guerra-Duarte; Evanguedes Kalapothakis; Carolina Campolina Rebello Horta. From taxonomy to molecular characterization of brown spider venom: An overview focused on Loxosceles similis. Toxicon 2019, 173, 5 -19.

AMA Style

Bárbara Bruna Ribeiro de Oliveira-Mendes, Maria Chatzaki, Douglas Ferreira Sales-Medina, Hortênsia Gomes Leal, Ray van der Veer, Gabriela Lago Biscoto, Priscila Mendes Gonçalves, Thais Soares da Silva, Clara Guerra-Duarte, Evanguedes Kalapothakis, Carolina Campolina Rebello Horta. From taxonomy to molecular characterization of brown spider venom: An overview focused on Loxosceles similis. Toxicon. 2019; 173 ():5-19.

Chicago/Turabian Style

Bárbara Bruna Ribeiro de Oliveira-Mendes; Maria Chatzaki; Douglas Ferreira Sales-Medina; Hortênsia Gomes Leal; Ray van der Veer; Gabriela Lago Biscoto; Priscila Mendes Gonçalves; Thais Soares da Silva; Clara Guerra-Duarte; Evanguedes Kalapothakis; Carolina Campolina Rebello Horta. 2019. "From taxonomy to molecular characterization of brown spider venom: An overview focused on Loxosceles similis." Toxicon 173, no. : 5-19.

Original research article
Published: 21 October 2019 in Frontiers in Immunology
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Accidents involving Micrurus snakes are not the most common ones but are noteworthy due to their severity. Victims envenomed by Micrurus snakes are at high risk of death and therefore must be treated with coral antivenom. In Brazil, the immunization mixture used to fabricate coral antivenom contains Micrurus frontalis and Micrurus corallinus venoms, which are difficult to be obtained in adequate amounts. Different approaches to solve the venom limitation problem have been attempted, including the use of synthetic and recombinant antigens as substitutes. The present work proposes a combined immunization protocol, using priming doses of M. frontalis venom and booster doses of synthetic B-cell epitopes derived from M. corallinus toxins (four three-finger toxins-3FTX; and one phospholipase A2-PLA2) to obtain coral antivenom in a rabbit model. Immunized animals elicited a humoral response against both M. frontalis and M. corallinus venoms, as detected by sera reactivity in ELISA and Western Blot. Relevant cross-reactivity of the obtained sera with other Micrurus species (Micrurus altirostris, Micrurus lemniscatus, Micrurus spixii, Micrurus surinamensis) venoms was also observed. The elicited antibodies were able to neutralize PLA2 activity of both M. frontalis and M. corallinus venoms. In vivo, immunized rabbit sera completely protected mice from a challenge with 1.5 median lethal dose (LD50) of M. corallinus venom and 50% of mice challenged with 1.5 LD50 of M. frontalis venom. These results show that this combined protocol may be a suitable alternative to reduce the amount of venom used in coral antivenom production in Brazil.

ACS Style

Karen Larissa Pereira De Castro; Letícia Lopes-De-Souza; Daysiane De Oliveira; Ricardo Andrez Machado de Ávila; Ana Luiza Bittencourt Paiva; Cláudio F. De Freitas; Paulo Lee Ho; Carlos Delfin Chávez Olórtegui; Clara Guerra-Duarte. A Combined Strategy to Improve the Development of a Coral Antivenom Against Micrurus spp. Frontiers in Immunology 2019, 10, 2422 .

AMA Style

Karen Larissa Pereira De Castro, Letícia Lopes-De-Souza, Daysiane De Oliveira, Ricardo Andrez Machado de Ávila, Ana Luiza Bittencourt Paiva, Cláudio F. De Freitas, Paulo Lee Ho, Carlos Delfin Chávez Olórtegui, Clara Guerra-Duarte. A Combined Strategy to Improve the Development of a Coral Antivenom Against Micrurus spp. Frontiers in Immunology. 2019; 10 ():2422.

Chicago/Turabian Style

Karen Larissa Pereira De Castro; Letícia Lopes-De-Souza; Daysiane De Oliveira; Ricardo Andrez Machado de Ávila; Ana Luiza Bittencourt Paiva; Cláudio F. De Freitas; Paulo Lee Ho; Carlos Delfin Chávez Olórtegui; Clara Guerra-Duarte. 2019. "A Combined Strategy to Improve the Development of a Coral Antivenom Against Micrurus spp." Frontiers in Immunology 10, no. : 2422.

Journal article
Published: 05 September 2019 in Toxicon
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Accidents with venomous snakes are a major health hazard in tropical countries. Bothrops genus is responsible for almost 80% of snakebites in Brazil. Immunotherapy is the only approved specific treatment against snake toxins and the production of therapeutic antivenoms requires quality control tests to determine their neutralizing potency. Currently, these controls are performed by in vivo lethality neutralization, however, the inhibition of particular events produced by bothropic venoms such as coagulopathy, hemorrhage, edema or cytotoxic effects are also required. The aim of this work is to develop an in vitro alternative assay for antivenom pre-clinical evaluation. In this sense, we designed a cell viability assay using different amounts (0.2–10 μL/well) of low and high potency anti-bothropic sera, previously classified by the traditional in vivo test, for assessing the antivenom capacity to protect the cells against B. jararaca venom cytotoxicity (5xEC50 = 58.95 μg/mL). We found that high potency sera are more effective in neutralizing B. jararaca venom cytotoxicity when compared to low potency sera, which is in accordance to their pre-determined in vivo potency. Considering sera in vitro inhibitory concentration able to prevent 50% cell death (IC50) and their known in vivo potency, a cut-off point was determined to discriminate low and high potency sera. Our data provide insights for the development of an in vitro method which can determine the anti-bothropic antivenom potency during its production.

ACS Style

Letícia Lopes-De-Souza; Fernanda Costal-Oliveira; Stephanie Stransky; Cláudio Fonseca de Freitas; Clara Guerra-Duarte; Vania M.M. Braga; Carlos Chávez-Olórtegui. Development of a cell-based in vitro assay as a possible alternative for determining bothropic antivenom potency. Toxicon 2019, 170, 68 -76.

AMA Style

Letícia Lopes-De-Souza, Fernanda Costal-Oliveira, Stephanie Stransky, Cláudio Fonseca de Freitas, Clara Guerra-Duarte, Vania M.M. Braga, Carlos Chávez-Olórtegui. Development of a cell-based in vitro assay as a possible alternative for determining bothropic antivenom potency. Toxicon. 2019; 170 ():68-76.

Chicago/Turabian Style

Letícia Lopes-De-Souza; Fernanda Costal-Oliveira; Stephanie Stransky; Cláudio Fonseca de Freitas; Clara Guerra-Duarte; Vania M.M. Braga; Carlos Chávez-Olórtegui. 2019. "Development of a cell-based in vitro assay as a possible alternative for determining bothropic antivenom potency." Toxicon 170, no. : 68-76.

Journal article
Published: 30 August 2019 in Biochimie
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Loxosceles spiders are found in almost all countries of South America. In Peru, Loxosceles laeta species is the main responsible for the accidents caused by poisonous animals, being known as “killer spiders”, due to the large number of fatal accidents observed. Astacin-like metalloproteases, named LALPs (Loxosceles astacin-like metalloproteases) are highly expressed in Loxosceles spiders venom gland. These proteases may be involved in hemorrhage and venom spreading, being relevant to the envenoming proccess. Thus, the aim of this work was to analyze Peruvian L. laeta venom gland transcripts using bioinformatics tools, focusing on LALPs. A cDNA library from Peruvian L. laeta venom glands was constructed and sequenced by MiSeq (Illumina) sequencer. After assembly, the resulting sequences were annotated, seeking out for similarity with previously described LALPs. Nine possible LALPs isoforms from Peruvian L. laeta venom were identified and the results were validated by in silico and in vitro experiments. This study contributes to a better understanding of the molecular diversity of Loxosceles venom and provide insights about the action of LALPs.

ACS Style

Raíssa Medina-Santos; Clara Guerra-Duarte; Sabrina De Almeida Lima; Fernanda Costal-Oliveira; Priscilla Alves de Aquino; Anderson Oliveira Do Carmo; César Bonilla Ferreyra; Edgar E. Gonzalez-Kozlova; Evanguedes Kalapothakis; Carlos Chávez-Olórtegui. Diversity of astacin-like metalloproteases identified by transcriptomic analysis in Peruvian Loxosceles laeta spider venom and in vitro activity characterization. Biochimie 2019, 167, 81 -92.

AMA Style

Raíssa Medina-Santos, Clara Guerra-Duarte, Sabrina De Almeida Lima, Fernanda Costal-Oliveira, Priscilla Alves de Aquino, Anderson Oliveira Do Carmo, César Bonilla Ferreyra, Edgar E. Gonzalez-Kozlova, Evanguedes Kalapothakis, Carlos Chávez-Olórtegui. Diversity of astacin-like metalloproteases identified by transcriptomic analysis in Peruvian Loxosceles laeta spider venom and in vitro activity characterization. Biochimie. 2019; 167 ():81-92.

Chicago/Turabian Style

Raíssa Medina-Santos; Clara Guerra-Duarte; Sabrina De Almeida Lima; Fernanda Costal-Oliveira; Priscilla Alves de Aquino; Anderson Oliveira Do Carmo; César Bonilla Ferreyra; Edgar E. Gonzalez-Kozlova; Evanguedes Kalapothakis; Carlos Chávez-Olórtegui. 2019. "Diversity of astacin-like metalloproteases identified by transcriptomic analysis in Peruvian Loxosceles laeta spider venom and in vitro activity characterization." Biochimie 167, no. : 81-92.

Review
Published: 19 June 2019 in Toxins
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Brown spider envenomation results in dermonecrosis with gravitational spreading characterized by a marked inflammatory reaction and with lower prevalence of systemic manifestations such as renal failure and hematological disturbances. Several toxins make up the venom of these species, and they are mainly peptides and proteins ranging from 5-40 kDa. The venoms have three major families of toxins: phospholipases-D, astacin-like metalloproteases, and the inhibitor cystine knot (ICK) peptides. Serine proteases, serpins, hyaluronidases, venom allergens, and a translationally controlled tumor protein (TCTP) are also present. Toxins hold essential biological properties that enable interactions with a range of distinct molecular targets. Therefore, the application of toxins as research tools and clinical products motivates repurposing their uses of interest. This review aims to discuss possibilities for brown spider venom toxins as putative models for designing molecules likely for therapeutics based on the status quo of brown spider venoms. Herein, we explore new possibilities for the venom components in the context of their biochemical and biological features, likewise their cellular targets, three-dimensional structures, and mechanisms of action.

ACS Style

Daniele Moreira; Fernando Hitomi Matsubara; Zelinda Schemczssen-Graeff; Elidiana De Bona; Vanessa Ribeiro Heidemann; Clara Guerra-Duarte; Luiza Helena Gremski; Carlos Chávez-Olórtegui; Andrea Senff-Ribeiro; Olga Meiri Chaim; Raghuvir Krishnaswamy Arni; Silvio Sanches Veiga. Brown Spider (Loxosceles) Venom Toxins as Potential Biotools for the Development of Novel Therapeutics. Toxins 2019, 11, 355 .

AMA Style

Daniele Moreira, Fernando Hitomi Matsubara, Zelinda Schemczssen-Graeff, Elidiana De Bona, Vanessa Ribeiro Heidemann, Clara Guerra-Duarte, Luiza Helena Gremski, Carlos Chávez-Olórtegui, Andrea Senff-Ribeiro, Olga Meiri Chaim, Raghuvir Krishnaswamy Arni, Silvio Sanches Veiga. Brown Spider (Loxosceles) Venom Toxins as Potential Biotools for the Development of Novel Therapeutics. Toxins. 2019; 11 (6):355.

Chicago/Turabian Style

Daniele Moreira; Fernando Hitomi Matsubara; Zelinda Schemczssen-Graeff; Elidiana De Bona; Vanessa Ribeiro Heidemann; Clara Guerra-Duarte; Luiza Helena Gremski; Carlos Chávez-Olórtegui; Andrea Senff-Ribeiro; Olga Meiri Chaim; Raghuvir Krishnaswamy Arni; Silvio Sanches Veiga. 2019. "Brown Spider (Loxosceles) Venom Toxins as Potential Biotools for the Development of Novel Therapeutics." Toxins 11, no. 6: 355.

Journal article
Published: 14 June 2019 in Toxicon
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Hyaluronidases (HYALs) are enzymes ubiquitously found in venoms from diverse animals and seem to be related to venom spreading. HYAL activity might be important to Tityus spp. envenoming, since anti-Tityus serrulatus HYAL (TsHYAL) rabbit antibodies neutralize T. serrulatus venom (TsV) lethality. The present work aimed to verify and compare HYAL activity of venoms from other Brazilian Tityus spp. (Tityus bahiensis, Tityus stigmurus and Tityus obscurus) and to test whether anti-TsHYAL antibodies and Brazilian horse therapeutic scorpion antivenom (produced by Fundação Ezequiel Dias (FUNED), Butantan and Vital Brazil Institutes) can recognize and inhibit HYAL activity from these venoms. In ELISA assays, anti-TsHYAL and scorpion antivenoms recognized T. serrulatus, T. bahiensis and T. stigmurus venoms, however, they demonstrated weaker reaction with T. obscurus, which was also observed in Western blotting assay. Epitope mapping by SPOT assay revealed different binding patterns for each antivenom. The assay showed a weaker binding of scorpion antivenom produced by FUNED to peptides recognized by anti-TsHYAL antibodies. Anti-TsHYAL antibodies and antivenoms produced by Butantan and Vital Brazil institutes inhibited HYAL activity of all tested venoms in vitro, whereas FUNED antivenom did not show the same property. These results call attention to the importance of hyaluronidase inhibition, that can aid the improvement of antivenom production.

ACS Style

Clara Guerra-Duarte; Carolina Campolina Rebello Horta; Bárbara Bruna Ribeiro Oliveira-Mendes; Bárbara De Freitas Magalhães; Fernanda Costal-Oliveira; Stephanie Stransky; Cláudio Fonseca de Freitas; Délio Campolina; Pedro Pereira De Oliveira Pardal; Rejane Lira-Da-Silva; Ricardo Andrés Machado de Ávila; Evanguedes Kalapothakis; Carlos Chávez-Olórtegui. Determination of hyaluronidase activity in Tityus spp. Scorpion venoms and its inhibition by Brazilian antivenoms. Toxicon 2019, 167, 134 -143.

AMA Style

Clara Guerra-Duarte, Carolina Campolina Rebello Horta, Bárbara Bruna Ribeiro Oliveira-Mendes, Bárbara De Freitas Magalhães, Fernanda Costal-Oliveira, Stephanie Stransky, Cláudio Fonseca de Freitas, Délio Campolina, Pedro Pereira De Oliveira Pardal, Rejane Lira-Da-Silva, Ricardo Andrés Machado de Ávila, Evanguedes Kalapothakis, Carlos Chávez-Olórtegui. Determination of hyaluronidase activity in Tityus spp. Scorpion venoms and its inhibition by Brazilian antivenoms. Toxicon. 2019; 167 ():134-143.

Chicago/Turabian Style

Clara Guerra-Duarte; Carolina Campolina Rebello Horta; Bárbara Bruna Ribeiro Oliveira-Mendes; Bárbara De Freitas Magalhães; Fernanda Costal-Oliveira; Stephanie Stransky; Cláudio Fonseca de Freitas; Délio Campolina; Pedro Pereira De Oliveira Pardal; Rejane Lira-Da-Silva; Ricardo Andrés Machado de Ávila; Evanguedes Kalapothakis; Carlos Chávez-Olórtegui. 2019. "Determination of hyaluronidase activity in Tityus spp. Scorpion venoms and its inhibition by Brazilian antivenoms." Toxicon 167, no. : 134-143.

Research article
Published: 19 April 2019 in PLOS Neglected Tropical Diseases
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The hyaluronidase enzyme is generally known as a spreading factor in animal venoms. Although its activity has been demonstrated in several organisms, a deeper knowledge about hyaluronidase and the venom spreading process from the bite/sting site until its elimination from the victim's body is still in need. Herein, we further pursued the goal of demonstrating the effects of inhibition of T. serrulatus venom (TsV) hyaluronidase on venom biodistribution. We used technetium-99m radiolabeled Tityus serrulatus venom (99mTc-TsV) to evaluate the venom distribution kinetics in mice. To understand the hyaluronidase's role in the venom's biodistribution, 99mTc-TsV was immunoneutralized with specific anti-T.serrulatus hyaluronidase serum. Venom biodistribution was monitored by scintigraphic images of treated animals and by measuring radioactivity levels in tissues as heart, liver, lungs, spleen, thyroid, and kidneys. In general, results revealed that hyaluronidase inhibition delays venom components distribution, when compared to the non-neutralized 99mTc-TsV control group. Scintigraphic images showed that the majority of the immunoneutralized venom is retained at the injection site, whereas non-treated venom is quickly biodistributed throughout the animal's body. At the first 30 min, concentration peaks are observed in the heart, liver, lungs, spleen, and thyroid, which gradually decreases over time. On the other hand, immunoneutralized 99mTc-TsV takes 240 min to reach high concentrations in the organs. A higher concentration of immunoneutralized 99mTc-TsV was observed in the kidneys in comparison with the non-treated venom. Further, in situ neutralization of 99mTc-TsV by anti-T.serrulatus hyaluronidase serum at zero, ten, and 30 min post venom injection showed that late inhibition of hyaluronidase can still affect venom biodistribution. In this assay, immunoneutralized 99mTc-TsV was accumulated in the bloodstream until 120 or 240 min after TsV injection, depending on anti-hyaluronidase administration time. Altogether, our data show that immunoneutralization of hyaluronidase prevents venom spreading from the injection site. By comparing TsV biodistribution in the absence or presence of anti-hyaluronidase serum, the results obtained in the present work show that hyaluronidase has a key role not only in the venom spreading from the inoculation point to the bloodstream, but also in venom biodistribution from the bloodstream to target organs. Our findings demonstrate that hyaluronidase is indeed an important spreading factor of TsV and its inhibition can be used as a novel first-aid strategy in envenoming.

ACS Style

Bárbara Bruna Ribeiro De Oliveira-Mendes; Sued Eustáquio Mendes Miranda; Douglas Ferreira Sales-Medina; Bárbara De Freitas Magalhães; Yan Kalapothakis; Renan Pedra De Souza; Valbert Nascimento Cardoso; Andre Luis de Barros; Clara Guerra-Duarte; Evanguedes Kalapothakis; Carolina Campolina Rebello Horta. Inhibition of Tityus serrulatus venom hyaluronidase affects venom biodistribution. PLOS Neglected Tropical Diseases 2019, 13, e0007048 .

AMA Style

Bárbara Bruna Ribeiro De Oliveira-Mendes, Sued Eustáquio Mendes Miranda, Douglas Ferreira Sales-Medina, Bárbara De Freitas Magalhães, Yan Kalapothakis, Renan Pedra De Souza, Valbert Nascimento Cardoso, Andre Luis de Barros, Clara Guerra-Duarte, Evanguedes Kalapothakis, Carolina Campolina Rebello Horta. Inhibition of Tityus serrulatus venom hyaluronidase affects venom biodistribution. PLOS Neglected Tropical Diseases. 2019; 13 (4):e0007048.

Chicago/Turabian Style

Bárbara Bruna Ribeiro De Oliveira-Mendes; Sued Eustáquio Mendes Miranda; Douglas Ferreira Sales-Medina; Bárbara De Freitas Magalhães; Yan Kalapothakis; Renan Pedra De Souza; Valbert Nascimento Cardoso; Andre Luis de Barros; Clara Guerra-Duarte; Evanguedes Kalapothakis; Carolina Campolina Rebello Horta. 2019. "Inhibition of Tityus serrulatus venom hyaluronidase affects venom biodistribution." PLOS Neglected Tropical Diseases 13, no. 4: e0007048.

Journal article
Published: 19 March 2019 in Toxicon
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Phoneutria nigriventer spider venom has been studied for more than 40 years and several components with pharmacological potential have been described in it. However, studies on venoms from other species of the Phoneutria genus are scarce. In this work, a conventional cDNA library from the species Phoneutria pertyi venom glands was constructed, aiming to identify novel putative cysteine-rich peptide toxins for the genus Phoneutria. 296 unique sequences were identified and 51 sequences corresponded to putative cysteine-rich peptide toxins. Besides cysteine-rich peptide toxins, other putative venom components such as protease inhibitors, defensins and serine proteinases were identified. Furthermore, by manual curation of the sequences with no match at UniProt, we were able to identify glycine-rich proteins (GRP), a class of venom component never described in Phoneutria genus. This work describes the first complete sequences of toxins from the venom of P. pertyi and reveals that, despite most of the retrieved toxins show a high identity to toxins identified in Phoneutria genus, novel putative toxins remains to be described.

ACS Style

Ana L.B. Paiva; Mauricio A. Mudadu; Elaine H.T. Pereira; Camila A. Marri; Clara Guerra-Duarte; Marcelo R.V. Diniz. Transcriptome analysis of the spider Phoneutria pertyi venom glands reveals novel venom components for the genus Phoneutria. Toxicon 2019, 163, 59 -69.

AMA Style

Ana L.B. Paiva, Mauricio A. Mudadu, Elaine H.T. Pereira, Camila A. Marri, Clara Guerra-Duarte, Marcelo R.V. Diniz. Transcriptome analysis of the spider Phoneutria pertyi venom glands reveals novel venom components for the genus Phoneutria. Toxicon. 2019; 163 ():59-69.

Chicago/Turabian Style

Ana L.B. Paiva; Mauricio A. Mudadu; Elaine H.T. Pereira; Camila A. Marri; Clara Guerra-Duarte; Marcelo R.V. Diniz. 2019. "Transcriptome analysis of the spider Phoneutria pertyi venom glands reveals novel venom components for the genus Phoneutria." Toxicon 163, no. : 59-69.

Journal article
Published: 28 January 2019 in Scientific Reports
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Snake venom L-amino acid oxidases (LAAOs) are flavoproteins, which perform diverse biological activities in the victim such as edema, myotoxicity and cytotoxicity, contributing to the development of clinical symptoms of envenomation. LAAO cytotoxicity has been described, but the temporal cascade of events leading to cell death has not been explored so far. This study evaluates the involvement of LAAO in dermonecrosis in mice and its cytotoxic effects in normal human keratinocytes, the major cell type in the epidermis, a tissue that undergoes extensive necrosis at the snakebite site. Pharmacological inhibition by the antioxidant NAC (N-acetyl cysteine) prevented B. atrox venom-induced necrosis. Consistent with the potential role of oxidative stress in wounding, treatment with purified LAAO decreased keratinocyte viability with an Effective Concentration (EC50) of 5.1 μg/mL. Cytotoxicity caused by LAAO was mediated by H2O2 and treated cells underwent autophagy, followed by apoptosis and necrosis. LAAO induced morphological alterations that precede cell death. Our results show the chronological events leading to cell death and the temporal resolution from autophagy, apoptosis and necrosis as distinct mechanisms triggered by LAAO. Fluorescently-labelled LAAO was efficiently and rapidly internalized by keratinocytes, suggesting that catalysis of intracellular substrates may contribute to LAAO toxicity. A better understanding of LAAO cytotoxicity and its mechanism of action will help to identify potential therapeutic strategies to ameliorate localized snake envenomation symptoms.

ACS Style

Fernanda Costal Oliveira; Stephanie Stransky; Clara Guerra-Duarte; Dayane Lorena Naves de Souza; Dan E. Vivas-Ruiz; Armando Yarlequé; Eladio Oswaldo Flores Sanchez; Carlos Chávez-Olórtegui; Vania Braga. L-amino acid oxidase from Bothrops atrox snake venom triggers autophagy, apoptosis and necrosis in normal human keratinocytes. Scientific Reports 2019, 9, 1 -14.

AMA Style

Fernanda Costal Oliveira, Stephanie Stransky, Clara Guerra-Duarte, Dayane Lorena Naves de Souza, Dan E. Vivas-Ruiz, Armando Yarlequé, Eladio Oswaldo Flores Sanchez, Carlos Chávez-Olórtegui, Vania Braga. L-amino acid oxidase from Bothrops atrox snake venom triggers autophagy, apoptosis and necrosis in normal human keratinocytes. Scientific Reports. 2019; 9 (1):1-14.

Chicago/Turabian Style

Fernanda Costal Oliveira; Stephanie Stransky; Clara Guerra-Duarte; Dayane Lorena Naves de Souza; Dan E. Vivas-Ruiz; Armando Yarlequé; Eladio Oswaldo Flores Sanchez; Carlos Chávez-Olórtegui; Vania Braga. 2019. "L-amino acid oxidase from Bothrops atrox snake venom triggers autophagy, apoptosis and necrosis in normal human keratinocytes." Scientific Reports 9, no. 1: 1-14.

Preprint content
Published: 04 December 2018
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Background: The hyaluronidase enzyme is generally known as a spreading factor in animal venoms. Although its activity has been demonstrated in several organisms, a deeper knowledge about hyaluronidase and the venom spreading process from the bite/sting site until its elimination from the victim's body is still in need. Methods and principal findings: We used technetium-99m radiolabeled Tityus serrulatus venom (99mTc-TsV) to evaluate the venom distribution kinetics in mice. To understand the hyaluronidase’s role in the venom’s biodistribution, 99mTc-TsV was immunoneutralized with specific anti-T.serrulatus hyaluronidase serum. Venom biodistribution was monitored by scintigraphic images of treated animals and by measuring radioactivity levels in tissues as heart, liver, lungs, spleen, thyroid, and kidneys. In general, results revealed that hyaluronidase inhibition delays venom components distribution, when compared to the non-neutralized 99mTc-TsV control group. Scintigraphic images showed that the majority of the immunoneutralized venom is retained at the injection site, whereas non-treated venom is quickly biodistributed throughout the animal’s body. At the first 30 minutes, concentration peaks are observed in the heart, liver, lungs, spleen, and thyroid, which gradually decreases over time. On the other hand, immunoneutralized 99mTc-TsV takes 240 minutes to reach high concentrations in the organs. A higher concentration of immunoneutralized 99mTc-TsV was observed in the kidneys in comparison with the non-treated venom. Further, in situ neutralization of 99mTc-TsV by anti-T.serrulatus hyaluronidase serum at zero, ten, and 30 minutes post venom injection showed that late inhibition of hyaluronidase can still affect venom biodistribution. In this assay, immunoneutralized 99mTc-TsV was accumulated in the bloodstream until 120 or 240 minutes after TsV injection, depending on anti-hyaluronidase administration time. Altogether, our data show that immunoneutralization of hyaluronidase prevents venom spreading from the injection site. Conclusions: The results obtained in the present work show that hyaluronidase has a key role not only in the venom spreading from the inoculation point to the bloodstream, but also in venom biodistribution from the bloodstream to target organs. Our findings demonstrate that hyaluronidase is indeed an important spreading factor of TsV, and its inhibition can be used as a novel first-aid strategy in envenoming.

ACS Style

Bárbara Bruna Ribeiro De Oliveira-Mendes; Sued Eustáquio Mendes Miranda; Douglas Ferreira Sales-Medina; Bárbara De Freitas Magalhães; Yan Kalapothakis; Renan Pedra De Souza; Valbert Nascimento Cardoso; André Luís Branco De Barros; Clara Guerra-Duarte; Evanguedes Kalapothakis; Carolina Campolina Rebello Horta. Hyaluronidase: the spreading factor of Tityus serrulatus venom. 2018, 487298 .

AMA Style

Bárbara Bruna Ribeiro De Oliveira-Mendes, Sued Eustáquio Mendes Miranda, Douglas Ferreira Sales-Medina, Bárbara De Freitas Magalhães, Yan Kalapothakis, Renan Pedra De Souza, Valbert Nascimento Cardoso, André Luís Branco De Barros, Clara Guerra-Duarte, Evanguedes Kalapothakis, Carolina Campolina Rebello Horta. Hyaluronidase: the spreading factor of Tityus serrulatus venom. . 2018; ():487298.

Chicago/Turabian Style

Bárbara Bruna Ribeiro De Oliveira-Mendes; Sued Eustáquio Mendes Miranda; Douglas Ferreira Sales-Medina; Bárbara De Freitas Magalhães; Yan Kalapothakis; Renan Pedra De Souza; Valbert Nascimento Cardoso; André Luís Branco De Barros; Clara Guerra-Duarte; Evanguedes Kalapothakis; Carolina Campolina Rebello Horta. 2018. "Hyaluronidase: the spreading factor of Tityus serrulatus venom." , no. : 487298.

Journal article
Published: 03 November 2018 in Molecular Immunology
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Bothropasin is a hemorrhagic snake venom metalloproteinase (SVMP) from Bothrops jararaca venom, the snake responsible for most bites in Southeastern Brazil. SVMPs, such as bothropasin, are involved in the main bothropic envenoming symptoms, which include hemorrhage, inflammation, necrosis and blood coagulation deficiency. B-cell epitope mapping of SVMPs can lead to the identification of peptides capable of inducing neutralizing antibodies without causing toxic effects, therefore improving anti-venom production. Here, using the SPOT synthesis technique, we have identified an epitope located in the catalytic domain of bothropasin (202KARMYELANIVNEILRYLYMH222) which was synthesized and named BotEp1. The peptide was used to immunize Swiss mice and Anti-BotEp1 serum cross-reacted with bothropasin and crude venoms from B. jararaca and B. atrox venoms. Furthermore, Anti-BotEp1 antibodies were able to completely neutralize the hemorrhagic activity of a chromatographic fraction from B. jararaca venom, which contains hemorrhagic SVMPs. In addition, the coagulation activity of the hemorrhagic fraction showed to be diminished when tested in serum from rabbit immunized with BotEp1 (compared to serum from non-immunized animal). Our results show the identification of neutralizing epitopes in bothropasin and provide basis for the use of synthetic peptides to improve the production of immunotherapeutics.

ACS Style

Denis A. Molina Molina; Clara Guerra-Duarte; Dayane L. Naves de Souza; Fernanda Costal-Oliveira; Giovana Reis de Ávila; Vanete T. Soccol; Ricardo A. Machado-De-Ávila; Carlos Chávez-Olórtegui. Identification of a linear B-cell epitope in the catalytic domain of bothropasin, a metalloproteinase from Bothrops jararaca snake venom. Molecular Immunology 2018, 104, 20 -26.

AMA Style

Denis A. Molina Molina, Clara Guerra-Duarte, Dayane L. Naves de Souza, Fernanda Costal-Oliveira, Giovana Reis de Ávila, Vanete T. Soccol, Ricardo A. Machado-De-Ávila, Carlos Chávez-Olórtegui. Identification of a linear B-cell epitope in the catalytic domain of bothropasin, a metalloproteinase from Bothrops jararaca snake venom. Molecular Immunology. 2018; 104 ():20-26.

Chicago/Turabian Style

Denis A. Molina Molina; Clara Guerra-Duarte; Dayane L. Naves de Souza; Fernanda Costal-Oliveira; Giovana Reis de Ávila; Vanete T. Soccol; Ricardo A. Machado-De-Ávila; Carlos Chávez-Olórtegui. 2018. "Identification of a linear B-cell epitope in the catalytic domain of bothropasin, a metalloproteinase from Bothrops jararaca snake venom." Molecular Immunology 104, no. : 20-26.

Journal article
Published: 08 October 2018 in Scientific Reports
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Epitope identification is essential for developing effective antibodies that can detect and neutralize bioactive proteins. Computational prediction is a valuable and time-saving alternative for experimental identification. Current computational methods for epitope prediction are underused and undervalued due to their high false positive rate. In this work, we targeted common properties of linear B-cell epitopes identified in an individual protein class (metalloendopeptidases) and introduced an alternative method to reduce the false positive rate and increase accuracy, proposing to restrict predictive models to a single specific protein class. For this purpose, curated epitope sequences from metalloendopeptidases were transformed into frame-shifted Kmers (3 to 15 amino acid residues long). These Kmers were decomposed into a matrix of biochemical attributes and used to train a decision tree classifier. The resulting prediction model showed a lower false positive rate and greater area under the curve when compared to state-of-the-art methods. Our predictions were used for synthesizing peptides mimicking the predicted epitopes for immunization of mice. A predicted linear epitope that was previously undetected by an experimental immunoassay was able to induce neutralizing-antibody production in mice. Therefore, we present an improved prediction alternative and show that computationally identified epitopes can go undetected during experimental mapping.

ACS Style

Edgar Ernesto Gonzalez Kozlova; Loïc Cerf; Francisco Santos Schneider; Benjamin Thomas Viart; Christophe Nguyen; Bethina Trevisol Steiner; Sabrina De Almeida Lima; Franck Molina; Clara Guerra-Duarte; Liza Felicori; Carlos Delfin Chávez Olórtegui; Ricardo Andrez Machado-De-Ávila. Computational B-cell epitope identification and production of neutralizing murine antibodies against Atroxlysin-I. Scientific Reports 2018, 8, 1 -13.

AMA Style

Edgar Ernesto Gonzalez Kozlova, Loïc Cerf, Francisco Santos Schneider, Benjamin Thomas Viart, Christophe Nguyen, Bethina Trevisol Steiner, Sabrina De Almeida Lima, Franck Molina, Clara Guerra-Duarte, Liza Felicori, Carlos Delfin Chávez Olórtegui, Ricardo Andrez Machado-De-Ávila. Computational B-cell epitope identification and production of neutralizing murine antibodies against Atroxlysin-I. Scientific Reports. 2018; 8 (1):1-13.

Chicago/Turabian Style

Edgar Ernesto Gonzalez Kozlova; Loïc Cerf; Francisco Santos Schneider; Benjamin Thomas Viart; Christophe Nguyen; Bethina Trevisol Steiner; Sabrina De Almeida Lima; Franck Molina; Clara Guerra-Duarte; Liza Felicori; Carlos Delfin Chávez Olórtegui; Ricardo Andrez Machado-De-Ávila. 2018. "Computational B-cell epitope identification and production of neutralizing murine antibodies against Atroxlysin-I." Scientific Reports 8, no. 1: 1-13.

Review
Published: 10 September 2018 in Toxins
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Diagnostic tests for arachnid accidents remain unavailable for patients and clinicians. Together with snakes, these accidents are still a global medical concern, and are recognized as neglected tropical issues. Due to arachnid toxins’ fast mechanism of action, quick detection and quantification of venom is required to accelerate treatment decisions, rationalize therapy, and reduce costs and patient risks. This review aims to understand the current limitations for arachnid venom identification and quantification in biological samples. We benchmarked the already existing initiatives regarding test requirements (sample or biomarkers of choice), performances (time, detection limit, sensitivity and specificity) and their validation (on animal models or on samples from envenomed humans). Our analysis outlines unmet needs for improving diagnosis and consequently treatment of arachnid accidents. Hence, based on lessons from past attempts, we propose a road map for raising best practice guidelines, leading to recommendations for future progress in the development of arachnid diagnostic assays.

ACS Style

Camila Dias-Lopes; Ana Luiza Paiva; Clara Guerra-Duarte; Franck Molina; Liza Felicori. Venomous Arachnid Diagnostic Assays, Lessons from Past Attempts. Toxins 2018, 10, 365 .

AMA Style

Camila Dias-Lopes, Ana Luiza Paiva, Clara Guerra-Duarte, Franck Molina, Liza Felicori. Venomous Arachnid Diagnostic Assays, Lessons from Past Attempts. Toxins. 2018; 10 (9):365.

Chicago/Turabian Style

Camila Dias-Lopes; Ana Luiza Paiva; Clara Guerra-Duarte; Franck Molina; Liza Felicori. 2018. "Venomous Arachnid Diagnostic Assays, Lessons from Past Attempts." Toxins 10, no. 9: 365.