Leprosy, an infectious disease caused by Mycobacterium leprae, affects millions of people worldwide. However, little is known regarding its molecular pathophysiological mechanisms. In this study, a comprehensive assessment of human mRNA was performed on leprosy skin lesions by using DNA chip microarrays, which included the entire spectrum of the disease along with its reactional states. Sixty-six samples from leprotic lesions (10TT, 10BT, 10BB, 10BL, 4LL, 14R1, and 10R2) and nine skin biopsies from healthy individuals were used as controls (CC) (ages ranged from 06 to 83 years, 48 were male and 29 female). The evaluation identified 1,580 differentially expressed mRNAs [Fold Change (FC)≥2.0, p<0.05] in diseased lesions versus healthy controls. Some of these genes were observed in all forms of the disease (CD2, CD27, chit1, FA2H, FAM26F, GZMB, MMP9, SLAMF7, UBD) and others were exclusive to reactional forms (Type "1" reaction: GPNMB, IL1B, MICAL2, FOXQ1; Type "2" reaction: AKR1B10, FAM180B, FOXQ1, NNMT, NR1D1, PTX3, TNFRSF25). In literature, these mRNAs have been associated with numerous pathophysiological processes and signaling pathways and are present in a large number of diseases. The role of these mRNAs maybe studied in the context of developing new diagnostic markers and therapeutic targets for leprosy.

Aim: To investigate the immune response of disseminated Ryzopus oryzae infection in immunocompetent mice. Methods: C57Bl/6, BALB/c and Swiss wild-type mice were intravenously infected with R. oryza...

Jorge Lobo's disease (Lacaziosis) is a subcutaneous infection of humans living in the Amazon region of Latin America, and in dolphins inhabiting the east coastal areas of the United States. The disease mainly affects people from rural areas living or working in close contact with vegetation and aquatic environments. Most patients refer having developed lesions after accidental trauma with plant thorns or insect bites. Inter-human transmission has never been confirmed suggesting that Lacazia loboi is acquired from environmental propagules.

Leprosy, a chronic infectious disease caused by Mycobacterium leprae, is a major public health problem in poor and developing countries of the Americas, Africa, and Asia. MicroRNAs (miRNAs), which are small non-coding RNAs (18–24 nucleotides), play an important role in regulating cell and tissue homeostasis through translational downregulation of messenger RNAs. Deregulation of miRNA expression is important for the pathogenesis of a wide variety of neoplastic and non-neoplastic diseases, and has been the focus of many publications; however, studies on the expression of miRNAs in leprosy are rare. Herein, an extensive evaluation of differentially expressed miRNAs was performed on leprosy skin lesions using microarrays. Leprosy patients, classified according to Ridley & Jopling’s classification or reactional states (R1 and R2), and healthy controls (HC) were included. Punch biopsies were collected from the borders of leprosy lesions (10 tuberculoid, 10 borderline tuberculoid, 10 borderline borderline, 10 borderline lepromatous, four lepromatous, 14 R1, and nine R2) and from nine HCs. miRNA expression profiles were obtained using the Agilent Microarray platform with miRBase, which consists of 1368 Homo sapiens (hsa)-miRNA candidates. TaqMan quantitative real-time reverse transcription polymerase chain reaction (RT-PCR) was used to validate differentially expressed miRNAs. Sixty-four differentially expressed miRNAs, including 50 upregulated and 14 downregulated [Fold Change (FC) ≥ 2.0, p-value ≤ 0.05] were identified after comparing samples from patients to those of controls. Twenty differentially expressed miRNAs were identified exclusively in the reactional samples (14 type 1 and six type 2). Eight miRNAs were validated by RT-PCR, including seven upregulated (hsa-miR-142-3p, hsa-miR-142-5p, hsa-miR-146b-5p, hsa-miR-342-3p, hsa-miR-361-3p, hsa-miR-3653, and hsa-miR-484) and one downregulated (hsa-miR-1290). These miRNAs were differentially expressed in leprosy and several other diseases, especially those related to the immune response. Moreover, the integration of analysis of validated mi/mRNAs obtained from the same samples allowed target pairs opposite expression pattern of has-miRNA-142-3p and AKR1B10, has-miRNA-342-3p and FAM180b, and has-miRNA-484 and FASN. This study identified several miRNAs that might play an important role in the molecular pathogenesis of the disease. Moreover, these deregulated miRNAs and their respective signaling pathways might be useful as therapeutic markers, therapeutic targets, which could help in the development

The in vitro cultivation of M. leprae has not been possible since it was described as causing leprosy, and the limitation of animal models for clinical aspects makes studies on leprosy and bacteria–human host interaction a challenge. Our aim was to standardize the ex vivo skin model (hOSEC) to maintenance and study of M. leprae as an alternative animal model. Bacillary suspensions were inoculated into human skin explants and sustained in DMEM medium for 60 days. Explants were evaluated by RT-PCR-16SrRNA and cytokine gene expression. The viability and infectivity of bacilli recovered from explants (D28 and D60) were evaluated using the Shepard’s model. All explants were RT-PCR-16SrRNA positive. The viability and infectivity of recovered bacilli from explants, analyzed after 5 months of inoculation in mice, showed an average positivity of 31%, with the highest positivity in the D28 groups (80%). Furthermore, our work showed different patterns in cytokine gene expression (TGF-β, IL-10, IL-8, and TNF-α) in the presence of alive or dead bacilli. Although changes can be made to improve future experiments, our results have demonstrated that it is possible to use the hOSEC to maintain M. leprae for 60 days, interacting with the host system, an important step in the development of experimental models for studies on the biology of the bacillus, its interactions, and drug susceptibility.