Igor Almeida

Prof. Igor Almeida

Border Biomedical Research Center (BBRC), Department of Biological Sciences, University of Texas at El Paso (UTEP), El Paso, TX 79968, USA

Research Focus & Metrics

Academic Career Length

34Years (1993-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 November 1996 in The Lancet
Verified
Journal Article
Closed access
AAAna Lucia S Sgambatti de Andrade
Ana Lucia S Sgambatti de Andrade
FZFabio Zicker
Fabio Zicker
RORenato Mauricio de Oliveira
Renato Mauricio de Oliveira
SSSimonne Almeida e Silva
Simonne Almeida e Silva
ALAlejandro Luquetti
Alejandro Luquetti
CMCelina Maria Turchi Martelli
Celina Maria Turchi Martelli

6 October 2014 in Cellular Microbiology
Verified
Journal Article
Open access
PDF file
GVGabriele Vargas
Gabriele Vargas
JRJuliana D. B. Rocha
Juliana D. B. Rocha
DODebora Leite Oliveira
Debora Leite Oliveira
PAPriscila Costa Albuquerque
Priscila Costa Albuquerque
SFSusana Frases
Susana Frases
LNLeonardo Nimrichter
Leonardo Nimrichter
The release of extracellular vesicles (EV) by fungal organisms is considered an alternative transport mechanism to trans‐cell wall passage of macromolecules. Previous studies have revealed the presence of EV in culture supernatants from fungal pathogens, such as Cryptococcus neoformans, Histoplasma capsulatum, Paracoccidioides brasiliensis, Sporothrix schenckii, Malassezia sympodialis and Candida albicans. Here we investigated the size, composition, kinetics of internalization by bone marrow‐derived murine macrophages (MO) and dendritic cells (DC), and the immunomodulatory activity of C. albicans EV. We also evaluated the impact of EV on fungal virulence using the Galleria mellonella larvae model. By transmission electron microscopy and dynamic light scattering, we identified two populations ranging from 50 to 100 nm and 350 to 850 nm. Two predominant seroreactive proteins (27 kDa and 37 kDa) and a group of polydispersed mannoproteins were observed in EV by immunoblotting analysis. Proteomic analysis of C. albicans EV revealed proteins related to pathogenesis, cell organization, carbohydrate and lipid metabolism, response to stress, and several other functions. The major lipids detected by thin‐layer chromatography were ergosterol, lanosterol and glucosylceramide. Short exposure of MO to EV resulted in internalization of these vesicles and production of nitric oxide, interleukin (IL)‐12, transforming growth factor‐beta (TGF‐β) and IL‐10. Similarly, EV‐treated DC produced IL‐12p40, IL‐10 and tumour necrosis factor‐alpha. In addition, EV treatment induced the up‐regulation of CD86 and major histocompatibility complex class‐II (MHC‐II). Inoculation of G. mellonella larvae with EV followed by challenge with C. albicans reduced the number of recovered viable yeasts in comparison with infected larvae control. Taken together, our results demonstrate that C. albicans EV were immunologically active and could potentially interfere with the host responses in the setting of invasive candidiasis.

1 January 2016 in Cell
Verified
Journal Article
Closed access
ASAnthony J. Szempruch
Anthony J. Szempruch
SSSteven E. Sykes
Steven E. Sykes
RKRudo Kieft
Rudo Kieft
LDLauren Dennison
Lauren Dennison
ABAllison C. Becker
Allison C. Becker
JHJohn M. Harrington
John M. Harrington

16 January 2018 in The Lancet Infectious Diseases
Verified
Journal Article
Closed access
FTFaustino Torrico
Faustino Torrico
JGJoaquim Gascon
Joaquim Gascon
LOLourdes Ortiz
Lourdes Ortiz
CACristina Alonso-Vega
Cristina Alonso-Vega
Maria Jesús PinazoMaria Jesús Pinazo
Maria Jesús Pinazo
WJWladimiro Jimenez
Wladimiro Jimenez

4 January 2013 in Journal of Proteome Research
Verified
Journal Article
Closed access
EBEthel Bayer-Santos
Ethel Bayer-Santos
CAClemente Aguilar-Bonavides
Clemente Aguilar-Bonavides
SRSilas Pessini Rodrigues
Silas Pessini Rodrigues
ECEsteban M Cordero
Esteban M Cordero
AMAlexandre F. Marques
Alexandre F. Marques
Igor AlmeidaIgor Almeida
Igor Almeida

1 January 2014 in Journal of Extracellular Vesicles
Verified
Journal Article
Open access
PDF file
AMAntonio Marcilla
Antonio Marcilla
LMLorena Martin‐Jaular
Lorena Martin‐Jaular
María TrelisMaría Trelis
María Trelis
AMArmando de Menezes‐Neto
Armando de Menezes‐Neto
AOAntonio Osuna
Antonio Osuna
HPHernando Del Portillo
Hernando Del Portillo
Parasitic diseases affect billions of people and are considered a major public health issue. Close to 400 species are estimated to parasitize humans, of which around 90 are responsible for great clinical burden and mortality rates. Unfortunately, they are largely neglected as they are mainly endemic to poor regions. Of relevance to this review, there is accumulating evidence of the release of extracellular vesicles (EVs) in parasitic diseases, acting both in parasite–parasite inter‐communication as well as in parasite–host interactions. EVs participate in the dissemination of the pathogen and play a role in the regulation of the host immune systems. Production of EVs from parasites or parasitized cells has been described for a number of parasitic infections. In this review, we provide the most relevant findings of the involvement of EVs in intercellular communication, modulation of immune responses, involvement in pathology, and their potential as new diagnostic tools and therapeutic agents in some of the major human parasitic pathogens.