Project description:Here we report the data generated by short-read sequencing of mRNA (polyA) isolated from granuloma annulare and leprosy skin lesions. Our main aim was to identify putative mRNA biomarkers for distinguishing leprosy from other differential diagnoses. Additionally, we also explored the distinction between MB and PB by using differential expression analysis as well as training a penalized logistic regression to select important features. Our results showed that few genes are enough to differentiate leprosy lesions, including paucibacillary cases, from other morphological and histopathological similar skin diseases. Some of these genes have been replicated in a larger and more heterogeneous sample with RT-qPCR, validating their classification potential. We also suggest important novel gene candidates to improve our understanding of molecular differences between MB and PB lesions, which could either pinpoint new pathways and targets for host-based specialized adjuvant treatment for leprosy. Finally, this dataset has been used to explore the relationship between cornification and keratinocyte-related genes and TGFB-mediated epithelial-mesenchymal transition (EMT), which could indicate that in skin, M. leprae could be de-differentiating, directly or indirectly, other cell types into a progenitor/stem-like phenotype, facilitating mycobacterial survival and migration within the host. Alternatively, this could highlight which pathways are activated during granuloma formation and/or skin barrier assembly/disassembly.
Project description:In this study, a comprehensive assessment of human miRNA was performed on leprosy skin lesions using DNA chip microarrays, which included the entire spectrum of the disease along with its reactional states. Sixty-eight 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 differentially expressed miRNAs [Fold Change (FC)≥2.0, p<0.05] in disease lesions versus healthy controls or between them. Some of these miRNAs were validated by RT-PCR.
Project description:Skin biopsy specimens of skin lesions were profiled for miRNA expression. In this study, we indentified miRNA species that were differentially expressed in the skin lesions of either the lepromatous or tuberculoid forms of leprosy. One miRNA species, hsa-mir-21, found in the lepromatous lesions was capable of downregulating the vitamin D-dependent antimicrobial pathway. Scalpel or punch skin biopsy specimens were obtained after informed consent from patients with tuberculoid leprosy and patients with lepromatous leprosy at the time of diagnosis. Specimens were embedded in OCT medium, snap-frozen in liquid nitrogen and stored at 80°C until sectioning.
Project description:Skin biopsy specimens of skin lesions were profiled for miRNA expression. In this study, we indentified miRNA species that were differentially expressed in the skin lesions of either the lepromatous or tuberculoid forms of leprosy. One miRNA species, hsa-mir-21, found in the lepromatous lesions was capable of downregulating the vitamin D-dependent antimicrobial pathway.
Project description:Effective innate immunity against many microbial pathogens requires macrophage programs that upregulate phagocytosis and direct antimicrobial pathways, two functions generally assumed to be coordinately regulated. Here the regulation of these key functions was investigated in human blood-derived macrophages. IL-10 induced the phagocytic pathway, including CD209 and scavenger receptors, resulting in phagocytosis of mycobacteria and oxLDL. IL-15 induced the vitamin D-dependent antimicrobial pathway and CD209, yet the cells were less phagocytic. The differential regulation of macrophage functional programs was confirmed by analysis of the spectrum of leprosy lesions: the macrophage phagocytosis pathway was prominent in the clinically progressive, multibacillary form, whereas the vitamin D-dependent antimicrobial pathway predominated in the self-limited form of the disease and in patients undergoing reversal reactions from the multibacillary to the self-limited form. These data indicate that macrophage programs for phagocytosis and antimicrobial responses are distinct and differentially regulated in innate immunity in bacterial infections. Experiment Overall Design: 7 LL lesions, 10 BT lesions, 7 RR lesions
Project description:Neutrophil recruitment is pivotal to host defense against microbial infection, but also contributes to the immunopathology of disease. We investigated the mechanism of neutrophil recruitment in human infectious disease by bioinformatic pathways analysis of the gene expression profiles in the skin lesions of leprosy. In erythema nodosum leprosum (ENL), which occurs in patients with lepromatous leprosy (L-lep), and is characterized by neutrophil infiltration in lesions, the most overrepresented biologic functional group was “cell movement” including E-selectin, which was coordinately regulated with IL-1. In vitro activation of TLR2, upregulated in ENL lesions, triggered induction of IL-1, which together with IFN-, induced E-selectin expression on, and neutrophil adhesion to endothelial cells. Thalidomide, an effective treatment for ENL, inhibited this neutrophil recruitment pathway. The gene expression profile of ENL lesions comprised an integrated pathway of TLR2/FcR activation, neutrophil migration and inflammation, providing insight into mechanisms of neutrophil recruitment in human infectious disease. 6 ENL skin lesions and 7 Lepromatous leprosy skin lesions
Project description:In this study, a comprehensive assessment of human mRNA was performed on leprosy skin lesions 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 differentially expressed mRNAs [Fold Change (FC)â¥2.0, p<0.05] in disease lesions versus healthy controls or between them. Some of these genes were validated by RT-PCR and/or immunohistochemistry. The sequence of events for this study followed the order below. Patients who were treated for leprosy were examined by leprologists and submitted to two biopsy procedures. One biopsy was processed for histopathological analysis, bacilloscopy and immunohistochemistry (IHC), the other was immediately stored in RNAlater® solution (Ambion) for further RNA extraction. Sixty-eight samples from leprotic lesions (10TT, 10BT, 10BB, 10BL, 4LL, 14R1, and 10R2) were selected for analysis. In addition, nine skin biopsies from healthy individuals were usedas controls (CC). Differentially expressed genes identified in the cDNA microarray assay were validated by quantitative RT-PCR and IHC.
Project description:Transcriptome profiles derived from the site of human disease has led to the identification of genes that contribute to pathogenesis, yet the complex mixture of cell types in these lesions has been an obstacle for defining specific mechanisms. Leprosy provides an outstanding model to study host defense and pathogenesis in a human infectious disease, given its clinical spectrum which interrelates with the host immunologic and pathologic responses. Here, we investigated gene expression profiles derived from skin lesions for each clinical subtype of leprosy, analyzing gene co-expression modules by cell type deconvolution. In lesions from tuberculoid leprosy patients, those with the self-limited form of the disease, dendritic cells were linked with MMP12 as part of a tissue remodeling network that contributes to granuloma formation. In lesions from lepromatous leprosy patients, those with disseminated disease, macrophages were linked with a gene network that programs phagocytosis. In erythema nodosum leprosum, neutrophil and endothelial cell gene networks were identified as part of the vasculitis that results in tissue injury. The present integrated computational approach provides a systems approach towards identifying cell-defined functional networks that contribute to host defense and immunopathology at the site of human infectious disease.
Project description:In this study, a comprehensive assessment of human mRNA was performed on leprosy skin lesions 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 differentially expressed mRNAs [Fold Change (FC)≥2.0, p<0.05] in disease lesions versus healthy controls or between them. Some of these genes were validated by RT-PCR and/or immunohistochemistry.
Project description:Granulomas are complex cellular structures comprised predominantly of macrophages and lymphocytes that function to contain and kill invading pathogens. Here, we investigated single cell phenotypes associated with antimicrobial responses in human leprosy granulomas by applying single cell and spatial sequencing to leprosy biopsy specimens. We focused on reversal reactions (RR), a dynamic process in which some patients with disseminated lepromatous leprosy (L-lep) transition towards self-limiting tuberculoid leprosy (T-lep), mounting effective antimicrobial responses. We identified a set of genes encoding proteins involved in antimicrobial responses that are differentially expressed in RR versus L-lep lesions, and regulated by IFN- and IL-1. By integrating the spatial coordinates of the key cell types and antimicrobial gene expression in RR and T-lep lesions, we constructed a map revealing the organized architecture of granulomas depicting compositional and functional layers by which macrophages, T cells, keratinocytes and fibroblasts contribute to the antimicrobial response.