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Cotti Piccinelli S, Tagliapietra M, Cavallaro T, Labella B, Risi B, Caria F, Damioli S, Poli L, Padovani A, Ferrari S, Filosto M. Leprosy Neuropathy in a Non-Endemic Area: A Clinical and Pathological Study. Biomedicines 2023; 11:2468. [PMID: 37760909 PMCID: PMC10525615 DOI: 10.3390/biomedicines11092468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 08/13/2023] [Accepted: 08/17/2023] [Indexed: 09/29/2023] Open
Abstract
The extent of nerve involvement in leprosy is highly variable in distribution and clinical presentation. Mononeuropathies, multiple mononeuropathies, and polyneuropathies can present both in the context of a cutaneous and/or systemic picture and in the form of pure neuritic leprosy (PNL). The differential diagnosis of leprosy neuropathy remains challenging because it is a very rare condition and, especially in Western countries, is often overlooked. We report one case of the polyneuropathic form of PNL (P-PNL) and one case of multiple mononeuropathy in paucibacillary leprosy. In both cases, the diagnosis was achieved by performing a sural nerve biopsy, which showed subverted structure, severe infiltration of inflammatory cells in nerve fascicles, granulomatous abnormalities, and the presence of alcohol-acid-resistant, Ziehl-Neelsen-positive bacilli inside the nerve bundles. Leprosy remains an endemic disease in many areas of the world, and globalization has led to the spread of cases in previously disease-free countries. In this perspective, our report emphasizes that the diagnostic possibility of leprosy neuropathy should always be taken into account, even in Western countries, in the differential diagnostic process of an acquired sensory polyneuropathy or multineuropathy and confirms that nerve biopsy remains a useful procedure in working up neuropathies with unknown etiology.
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Affiliation(s)
- Stefano Cotti Piccinelli
- Department of Clinical and Experimental Sciences, University of Brescia, 25100 Brescia, Italy; (S.C.P.); (B.L.); (B.R.); (A.P.)
- NeMO-Brescia Clinical Center for Neuromuscular Diseases, Guusago, 25064 Brescia, Italy; (F.C.); (S.D.)
| | - Matteo Tagliapietra
- Neurology Unit, Department of Neurosciences, Biomedicine and Movement Sciences, 37100 Verona, Italy; (M.T.); (T.C.); (S.F.)
| | - Tiziana Cavallaro
- Neurology Unit, Department of Neurosciences, Biomedicine and Movement Sciences, 37100 Verona, Italy; (M.T.); (T.C.); (S.F.)
| | - Beatrice Labella
- Department of Clinical and Experimental Sciences, University of Brescia, 25100 Brescia, Italy; (S.C.P.); (B.L.); (B.R.); (A.P.)
- Unit of Neurology, ASST Spedali Civili, 25100 Brescia, Italy;
| | - Barbara Risi
- Department of Clinical and Experimental Sciences, University of Brescia, 25100 Brescia, Italy; (S.C.P.); (B.L.); (B.R.); (A.P.)
- NeMO-Brescia Clinical Center for Neuromuscular Diseases, Guusago, 25064 Brescia, Italy; (F.C.); (S.D.)
| | - Filomena Caria
- NeMO-Brescia Clinical Center for Neuromuscular Diseases, Guusago, 25064 Brescia, Italy; (F.C.); (S.D.)
| | - Simona Damioli
- NeMO-Brescia Clinical Center for Neuromuscular Diseases, Guusago, 25064 Brescia, Italy; (F.C.); (S.D.)
| | - Loris Poli
- Unit of Neurology, ASST Spedali Civili, 25100 Brescia, Italy;
| | - Alessandro Padovani
- Department of Clinical and Experimental Sciences, University of Brescia, 25100 Brescia, Italy; (S.C.P.); (B.L.); (B.R.); (A.P.)
- Unit of Neurology, ASST Spedali Civili, 25100 Brescia, Italy;
| | - Sergio Ferrari
- Neurology Unit, Department of Neurosciences, Biomedicine and Movement Sciences, 37100 Verona, Italy; (M.T.); (T.C.); (S.F.)
| | - Massimiliano Filosto
- Department of Clinical and Experimental Sciences, University of Brescia, 25100 Brescia, Italy; (S.C.P.); (B.L.); (B.R.); (A.P.)
- NeMO-Brescia Clinical Center for Neuromuscular Diseases, Guusago, 25064 Brescia, Italy; (F.C.); (S.D.)
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2
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Ebenezer GJ, Pena MT, Daniel AS, Truman RW, Adams L, Duthie MS, Wagner K, Zampino S, Tolf E, Tsottles D, Polydefkis M. Mycobacterium leprae induces Schwann cell proliferation and migration in a denervated milieu following intracutaneous excision axotomy in nine-banded armadillos. Exp Neurol 2022; 352:114053. [PMID: 35341747 DOI: 10.1016/j.expneurol.2022.114053] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 02/15/2022] [Accepted: 03/21/2022] [Indexed: 01/23/2023]
Abstract
Nine-banded armadillos develop peripheral neuropathy after experimental Mycobacterium leprae infection that recapitulates human disease. We used an intracutaneous excision axotomy model to assess the effect of infection duration by M. leprae on axonal sprouting and Schwan cell density. 34 armadillos (17 naïve and 17 M. leprae-infected) underwent 3 mm skin biopsies to create an intracutaneous excision axotomy followed by a concentric 4-mm overlapping biopsy 3 and 12-months post M. leprae inoculation. A traditional distal leg biopsy was obtained at 15mo for intraepidermal nerve fiber (IENF) density. Serial skin sections were immunostained against a axons (PGP9.5, GAP43), and Schwann cells (p75, s100) to visualize regenerating nerves. Regenerative axons and proliferation of Schwann cells was measured and the rate of growth at each time point was assessed. Increasing anti-PGL antibody titers and intraneural M. leprae confirmed infection. 15mo following infection, there was evidence of axon loss with reduced distal leg IENF versus naïve armadillos, p < 0.05. This was associated with an increase in Schwann cell density (11,062 ± 2905 vs. 7561 ± 2715 cells/mm3, p < 0.01). Following excisional biopsy epidermal reinnervation increased monotonically at 30, 60 and 90 days; the regeneration rate was highest at 30 days, and decreased at 60 and 90 days. The reinnervation rate was highest among animals infected for 3mo vs those infected for 12mo or naïve animals (mean ± SD, 27.8 ± 7.2 vs.16.2 ± 5.8vs. 15.3 ± 6.5 mm/mm3, p < 0.05). The infected armadillos displayed a sustained Schwann cell proliferation across axotomy time points and duration of infection (3mo:182 ± 26, 12mo: 256 ± 126, naive: 139 ± 49 cells/day, p < 0.05). M. leprae infection is associated with sustained Schwann cell proliferation and distal limb nerve fiber loss. Rates of epidermal reinnervation were highest 3mo after infection and normalized by 12 mo of infection. We postulate that excess Schwann cell proliferation is the main pathogenic process and is deleterious to sensory axons. There is a compensatory initial increase in regeneration rates that may be an attempt to compensate for the injury, but it is not sustained and eventually followed by axon loss. Aberrant Schwann cell proliferation may be a novel therapeutic target to interrupt the pathogenic cascade of M. leprae.
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Affiliation(s)
| | - Maria T Pena
- DHHS/HRSA/HSB/National Hansen's Disease Program, Baton Rouge, LA 70816, USA
| | | | - Richard W Truman
- DHHS/HRSA/HSB/National Hansen's Disease Program, Baton Rouge, LA 70816, USA
| | - Linda Adams
- DHHS/HRSA/HSB/National Hansen's Disease Program, Baton Rouge, LA 70816, USA
| | | | - Kelly Wagner
- Neurology, Johns Hopkins University, Baltimore, MD, USA
| | | | - Eleanor Tolf
- Neurology, Johns Hopkins University, Baltimore, MD, USA
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3
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Barral TD, Rebouças MF, Loureiro D, Raynal JT, Sousa TJ, Moura-Costa LF, Azevedo V, Meyer R, Portela RW. Chemokine production induced by Corynebacterium pseudotuberculosis in a murine model. Braz J Microbiol 2022; 53:1019-1027. [PMID: 35138630 PMCID: PMC9151972 DOI: 10.1007/s42770-022-00694-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 02/01/2022] [Indexed: 02/01/2023] Open
Abstract
Corynebacterium pseudotuberculosis is the etiological agent of caseous lymphadenitis. The main clinical sign of this disease is the development of granulomas, especially in small ruminants; however, the pathways that are involved in the formation and maintenance of these granulomas are unknown. Cytokines and chemokines are responsible for the migration of immune cells to specific sites and tissues; therefore, it is possible that chemokines participate in abscess formation. This study aimed to evaluate the induction of chemokine production by two C. pseudotuberculosis strains in a murine model. A highly pathogenic (VD57) and an attenuated (T1) strain of C. pseudotuberculosis, as well as somatic and secreted antigens derived from these strains, was used to stimulate murine splenocytes. Then, the concentrations of the chemokines CCL-2, CCL-3, CCL-4, and CCL-5 and the cytokines IL-1 and TNF were measured in the culture supernatants. The VD57 strain had a higher ability to stimulate the production of chemokines when compared to T1 strain, especially in the early stages of stimulation, which can have an impact on granuloma formation. The T1 lysate antigen was able to stimulate most of the chemokines studied herein when compared to the other antigenic fractions of both strains. These results indicate that C. pseudotuberculosis is a chemokine production inducer, and the bacterial strains differ in their induction pattern, a situation that can be related to the specific behavior of each strain.
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Affiliation(s)
- Thiago Doria Barral
- Laboratory of Immunology and Molecular Biology, Institute of Health Sciences, Federal University of Bahia, Salvador, Bahia State, 40110-100, Brazil
| | - Miriam Flores Rebouças
- Laboratory of Immunology and Molecular Biology, Institute of Health Sciences, Federal University of Bahia, Salvador, Bahia State, 40110-100, Brazil
| | - Dan Loureiro
- Laboratory of Immunology and Molecular Biology, Institute of Health Sciences, Federal University of Bahia, Salvador, Bahia State, 40110-100, Brazil
| | - José Tadeu Raynal
- Laboratory of Immunology and Molecular Biology, Institute of Health Sciences, Federal University of Bahia, Salvador, Bahia State, 40110-100, Brazil
| | - Thiago Jesus Sousa
- Laboratory of Molecular and Cellular Genetics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais State, 31270-901, Brazil
| | - Lilia Ferreira Moura-Costa
- Laboratory of Immunology and Molecular Biology, Institute of Health Sciences, Federal University of Bahia, Salvador, Bahia State, 40110-100, Brazil
| | - Vasco Azevedo
- Laboratory of Molecular and Cellular Genetics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais State, 31270-901, Brazil
| | - Roberto Meyer
- Laboratory of Immunology and Molecular Biology, Institute of Health Sciences, Federal University of Bahia, Salvador, Bahia State, 40110-100, Brazil
| | - Ricardo Wagner Portela
- Laboratory of Immunology and Molecular Biology, Institute of Health Sciences, Federal University of Bahia, Salvador, Bahia State, 40110-100, Brazil.
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Barroso DH, Brandão JG, Andrade ESN, Correia ACB, Aquino DC, Chen ACR, Vernal S, de Araújo WN, da Mota LMH, Sampaio RNR, Kurizky PS, Gomes CM. Leprosy detection rate in patients under immunosuppression for the treatment of dermatological, rheumatological, and gastroenterological diseases: a systematic review of the literature and meta-analysis. BMC Infect Dis 2021; 21:347. [PMID: 33849463 PMCID: PMC8045377 DOI: 10.1186/s12879-021-06041-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 04/05/2021] [Indexed: 11/23/2022] Open
Abstract
Background Recently developed immunosuppressive drugs, especially TNF antagonists, may enhance the risk of granulomatous infections, including leprosy. We aimed to evaluate the leprosy detection rate in patients under immunosuppression due to rheumatological, dermatological and gastroenterological diseases. Methods We performed a systematic review of the literature by searching the PubMed, EMBASE, LILACS, Web of Science and Scielo databases through 2018. No date or language restrictions were applied. We included all articles that reported the occurrence of leprosy in patients under medication-induced immunosuppression. Results The search strategy resulted in 15,103 articles; finally, 20 articles were included, with 4 reporting longitudinal designs. The detection rate of leprosy ranged from 0.13 to 116.18 per 100,000 patients/year in the USA and Brazil, respectively. In the meta-analysis, the detection rate of cases of leprosy per 100,000 immunosuppressed patients with rheumatic diseases was 84 (detection rate = 0.00084; 95% CI = 0.0000–0.00266; I2 = 0%, p = 0.55). Conclusion Our analysis showed that leprosy was relatively frequently detected in medication-induced immunosuppressed patients suffering from rheumatological diseases, and further studies are needed. The lack of an active search for leprosy in the included articles precluded more precise conclusions. Trial registration This review is registered in PROSPERO with the registry number CRD42018116275. Supplementary Information The online version contains supplementary material available at 10.1186/s12879-021-06041-7.
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Affiliation(s)
- Daniel Holanda Barroso
- Programa de Pós-Graduação em Ciências Médicas, Faculdade de Medicina, Universidade de Brasília - UnB, Campus Universitário Darcy Ribeiro, Brasília, DF, CEP 70910-900, Brazil.
| | - Jurema Guerrieri Brandão
- Departamento de Doenças de Condições Crônicas e Infecções Sexualmente Transmissíveis - DCCI, Coordenação Geral de Vigilância das Doenças em Eliminação - CGDE, Secretaria de Vigilância em Saúde, Ministério da Saúde, Brasília, Brazil
| | - Elaine Silva Nascimento Andrade
- Departamento de Doenças de Condições Crônicas e Infecções Sexualmente Transmissíveis - DCCI, Coordenação Geral de Vigilância das Doenças em Eliminação - CGDE, Secretaria de Vigilância em Saúde, Ministério da Saúde, Brasília, Brazil.,Programa de Pós-Graduação em Saúde Coletiva, Faculdade de Medicina, Universidade de Brasília - UnB, Brasília, Brazil
| | | | - Danielle Costa Aquino
- Programa de Pós-Graduação em Ciências Médicas, Faculdade de Medicina, Universidade de Brasília - UnB, Campus Universitário Darcy Ribeiro, Brasília, DF, CEP 70910-900, Brazil
| | | | - Sebastian Vernal
- Departamento de Moléstias Infecciosas e Parasitárias, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil.,Departamento de Clínica Médica, Divisão de Dermatologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Wildo Navegantes de Araújo
- Programa de Pós-Graduação em Saúde Coletiva, Faculdade de Medicina, Universidade de Brasília - UnB, Brasília, Brazil.,Programa de Pós-Graduação em Medicina Tropical, Núcleo de Medicina Tropical, Universidade de Brasília - UnB, Brasília, Brazil.,National Institute for Science and Technology for Health Technology Assessment (IATS), Porto Alegre, RS, Brazil
| | - Lícia Maria Henrique da Mota
- Programa de Pós-Graduação em Ciências Médicas, Faculdade de Medicina, Universidade de Brasília - UnB, Campus Universitário Darcy Ribeiro, Brasília, DF, CEP 70910-900, Brazil
| | - Raimunda Nonata Ribeiro Sampaio
- Programa de Pós-Graduação em Ciências Médicas, Faculdade de Medicina, Universidade de Brasília - UnB, Campus Universitário Darcy Ribeiro, Brasília, DF, CEP 70910-900, Brazil
| | - Patrícia Shu Kurizky
- Programa de Pós-Graduação em Ciências Médicas, Faculdade de Medicina, Universidade de Brasília - UnB, Campus Universitário Darcy Ribeiro, Brasília, DF, CEP 70910-900, Brazil
| | - Ciro Martins Gomes
- Programa de Pós-Graduação em Ciências Médicas, Faculdade de Medicina, Universidade de Brasília - UnB, Campus Universitário Darcy Ribeiro, Brasília, DF, CEP 70910-900, Brazil. .,Faculdade de Medicina, Universidade de Brasília - UnB, Brasília, Brazil. .,Programa de Pós-Graduação em Medicina Tropical, Núcleo de Medicina Tropical, Universidade de Brasília - UnB, Brasília, Brazil.
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5
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Adams LB. Susceptibility and resistance in leprosy: Studies in the mouse model. Immunol Rev 2021; 301:157-174. [PMID: 33660297 PMCID: PMC8252540 DOI: 10.1111/imr.12960] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 02/01/2021] [Accepted: 02/02/2021] [Indexed: 12/24/2022]
Abstract
Leprosy is a chronic granulomatous infectious disease caused by the pathogen, Mycobacterium leprae, and the more recently discovered, M. lepromatosis. Described in 1873, M. leprae was among the first microorganisms to be proposed as a cause of a human infectious disease. As an obligate intracellular bacterium, it has still not thus far been reproducibly cultivated in axenic medium or cell cultures. Shepard's mouse footpad assay, therefore, was truly a breakthrough in leprosy research. The generation of immunosuppressed and genetically engineered mice, along with advances in molecular and cellular techniques, has since offered more tools for the study of the M. leprae–induced granuloma. While far from perfect, these new mouse models have provided insights into the immunoregulatory mechanisms responsible for the spectrum of this complex disease.
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Affiliation(s)
- Linda B Adams
- Department of Health and Human Services, Health Resources and Services Administration, Healthcare Systems Bureau, National Hansen's Disease Programs Laboratory Research Branch, Baton Rouge, LA, USA
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6
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Karamova AE, Semenova VG, Verbenko DA, Obraztsova OA, Vanchugova KM, Nikonorov AA, Deryabin DG, Solomka VS, Kubanov AA. Experimental Modeling of Leprosy in BALB/c, BALB/c Nude, CBA, and C57BL/6ТNF -/- Mice. Bull Exp Biol Med 2020; 169:836-839. [PMID: 33098510 DOI: 10.1007/s10517-020-04991-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Indexed: 10/23/2022]
Abstract
Leprosy was modeled in an experiment on BALB/c, BALB/cNude, CBA, and C57BL/6ТNF-/- mice using three Mycobacterium leprae strains obtained from patients with a diagnosis of A30 according to ICD-10 from different regions of the Russian Federation. Proliferation of M. leprae of the used strains showed a temporal-quantitative dependence on the used mouse line. CBA and BALB/cNude mice were optimal for strain R and BALB/c and BALB/cNude lines were optimal for strain I. BALB/cNude mice infected with strain I had low lifespan. M. leprae strain M showed low proliferation activity in BALB/cNude and C57BL/6ТNF-/- mice.
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Affiliation(s)
- A E Karamova
- State Research Center of Dermatovenereology and Cosmetology, Ministry of Health of the Russian Federation, Moscow, Russia
| | - V G Semenova
- State Research Center of Dermatovenereology and Cosmetology, Ministry of Health of the Russian Federation, Moscow, Russia
| | - D A Verbenko
- State Research Center of Dermatovenereology and Cosmetology, Ministry of Health of the Russian Federation, Moscow, Russia
| | - O A Obraztsova
- State Research Center of Dermatovenereology and Cosmetology, Ministry of Health of the Russian Federation, Moscow, Russia
| | - Kh M Vanchugova
- State Research Center of Dermatovenereology and Cosmetology, Ministry of Health of the Russian Federation, Moscow, Russia
| | - A A Nikonorov
- State Research Center of Dermatovenereology and Cosmetology, Ministry of Health of the Russian Federation, Moscow, Russia.
| | - D G Deryabin
- State Research Center of Dermatovenereology and Cosmetology, Ministry of Health of the Russian Federation, Moscow, Russia
| | - V S Solomka
- State Research Center of Dermatovenereology and Cosmetology, Ministry of Health of the Russian Federation, Moscow, Russia
| | - A A Kubanov
- State Research Center of Dermatovenereology and Cosmetology, Ministry of Health of the Russian Federation, Moscow, Russia
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7
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Mi Z, Liu H, Zhang F. Advances in the Immunology and Genetics of Leprosy. Front Immunol 2020; 11:567. [PMID: 32373110 PMCID: PMC7176874 DOI: 10.3389/fimmu.2020.00567] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 03/12/2020] [Indexed: 12/21/2022] Open
Abstract
Leprosy, a disease caused by the intracellular parasite Mycobacterium leprae or Mycobacterium lepromatosis, has affected humans for more than 4,000 years and is a stigmatized disease even now. Since clinical manifestations of leprosy patients present as an immune-related spectrum, leprosy is regarded as an ideal model for studying the interaction between host immune response and infection; in fact, the landscape of leprosy immune responses has been extensively investigated. Meanwhile, leprosy is to some extent a genetic disease because the genetic factors of hosts have long been considered major contributors to this disease. Many immune-related genes have been discovered to be associated with leprosy. However, immunological and genetic findings have rarely been studied and discussed together, and as a result, the effects of gene variants on leprosy immune responses and the molecular mechanisms of leprosy pathogenesis are largely unknown. In this context, we summarized advances in both the immunology and genetics of leprosy and discussed the perspective of the combination of immunological and genetic approaches in studying the molecular mechanism of leprosy pathogenesis. In our opinion, the integrating of immunological and genetic approaches in the future may be promising to elucidate the molecular mechanism of leprosy onset and how leprosy develops into different types of leprosy.
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Affiliation(s)
- Zihao Mi
- Shandong Provincial Hospital for Skin Diseases & Shandong Provincial Institute of Dermatology and Venereology, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, China
| | - Hong Liu
- Shandong Provincial Hospital for Skin Diseases & Shandong Provincial Institute of Dermatology and Venereology, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, China
| | - Furen Zhang
- Shandong Provincial Hospital for Skin Diseases & Shandong Provincial Institute of Dermatology and Venereology, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, China
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8
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Fonseca ABDL, Simon MDV, Cazzaniga RA, de Moura TR, de Almeida RP, Duthie MS, Reed SG, de Jesus AR. The influence of innate and adaptative immune responses on the differential clinical outcomes of leprosy. Infect Dis Poverty 2017; 6:5. [PMID: 28162092 PMCID: PMC5292790 DOI: 10.1186/s40249-016-0229-3] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 12/20/2016] [Indexed: 12/22/2022] Open
Abstract
Leprosy is a chronic infectious disease caused by Mycobacterium leprae. According to official reports from 121 countries across five WHO regions, there were 213 899 newly diagnosed cases in 2014. Although leprosy affects the skin and peripheral nerves, it can present across a spectrum of clinical and histopathological forms that are strongly influenced by the immune response of the infected individuals. These forms comprise the extremes of tuberculoid leprosy (TT), with a M. leprae-specific Th1, but also a Th17, response that limits M. leprae multiplication, through to lepromatous leprosy (LL), with M. leprae-specific Th2 and T regulatory responses that do not control M. leprae replication but rather allow bacterial dissemination. The interpolar borderline clinical forms present with similar, but less extreme, immune biases. Acute inflammatory episodes, known as leprosy reactions, are complications that may occur before, during or after treatment, and cause further neurological damages that can cause irreversible chronic disabilities. This review discusses the innate and adaptive immune responses, and their interactions, that are known to affect pathogenesis and influence the clinical outcome of leprosy.
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Affiliation(s)
- Adriana Barbosa de Lima Fonseca
- Department of Medicine, Molecular Biology Laboratory, University Hospital, Universidade Federal de Sergipe, São Cristóvão, Sergipe, Brazil
| | - Marise do Vale Simon
- Department of Medicine, Molecular Biology Laboratory, University Hospital, Universidade Federal de Sergipe, São Cristóvão, Sergipe, Brazil
| | - Rodrigo Anselmo Cazzaniga
- Department of Medicine, Molecular Biology Laboratory, University Hospital, Universidade Federal de Sergipe, São Cristóvão, Sergipe, Brazil
| | - Tatiana Rodrigues de Moura
- Department of Medicine, Molecular Biology Laboratory, University Hospital, Universidade Federal de Sergipe, São Cristóvão, Sergipe, Brazil
| | - Roque Pacheco de Almeida
- Department of Medicine, Molecular Biology Laboratory, University Hospital, Universidade Federal de Sergipe, São Cristóvão, Sergipe, Brazil.,Instituto de Investigação em Imunologia, Institutos Nacionais de Ciência e Tecnologia, CNPq, São Paulo, SP, Brazil
| | | | | | - Amelia Ribeiro de Jesus
- Department of Medicine, Molecular Biology Laboratory, University Hospital, Universidade Federal de Sergipe, São Cristóvão, Sergipe, Brazil. .,Instituto de Investigação em Imunologia, Institutos Nacionais de Ciência e Tecnologia, CNPq, São Paulo, SP, Brazil.
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9
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Wang Z, Sun Y, Fu X, Yu G, Wang C, Bao F, Yue Z, Li J, Sun L, Irwanto A, Yu Y, Chen M, Mi Z, Wang H, Huai P, Li Y, Du T, Yu W, Xia Y, Xiao H, You J, Li J, Yang Q, Wang N, Shang P, Niu G, Chi X, Wang X, Cao J, Cheng X, Liu H, Liu J, Zhang F. A large-scale genome-wide association and meta-analysis identified four novel susceptibility loci for leprosy. Nat Commun 2016; 7:13760. [PMID: 27976721 PMCID: PMC5172377 DOI: 10.1038/ncomms13760] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 10/31/2016] [Indexed: 11/18/2022] Open
Abstract
Leprosy, a chronic infectious disease, results from the uncultivable pathogen Mycobacterium leprae (M. leprae), and usually progresses to peripheral neuropathy and permanent progressive deformity if not treated. Previously published genetic studies have identified 18 gene/loci significantly associated with leprosy at the genome-wide significant level. However as a complex disease, only a small proportion of leprosy risk could be explained by those gene/loci. To further identify more susceptibility gene/loci, we hereby performed a three-stage GWAS comprising 8,156 leprosy patients and 15,610 controls of Chinese ancestry. Four novel loci were identified including rs6807915 on 3p25.2 (P=1.94 × 10−8, OR=0.89), rs4720118 on 7p14.3 (P=3.85 × 10−10, OR=1.16), rs55894533 on 8p23.1 (P=5.07 × 10−11, OR=1.15) and rs10100465 on 8q24.11 (P=2.85 × 10−11, OR=0.85). Altogether, these findings have provided new insight and significantly expanded our understanding of the genetic basis of leprosy.
Previous studies have shown genetic associations between leprosy and 18 different genes/loci. Here, Wang and colleagues perform genome-wide association study in Han Chinese leprosy patients and describe four novel loci to be associated to the disease.
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Affiliation(s)
- Zhenzhen Wang
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China
| | - Yonghu Sun
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China
| | - Xi'an Fu
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China.,School of Medicine, Shandong University, Jinan, Shandong 250000, China
| | - Gongqi Yu
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China.,School of Medicine and Life Science, University of Jinan-Shandong Academy of Medical Sciences, Jinan, Shandong 250022, China
| | - Chuan Wang
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China
| | - Fangfang Bao
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China
| | - Zhenhua Yue
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China.,School of Medicine, Shandong University, Jinan, Shandong 250000, China
| | - Jianke Li
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China.,Shandong Provincial Hospital for Skin Diseases, Shandong University, Jinan, Shandong 250000, China
| | - Lele Sun
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China
| | - Astrid Irwanto
- Human Genetics, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Yongxiang Yu
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China
| | - Mingfei Chen
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China
| | - Zihao Mi
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China
| | - Honglei Wang
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China.,School of Medicine, Shandong University, Jinan, Shandong 250000, China
| | - Pengcheng Huai
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China.,School of Medicine, Shandong University, Jinan, Shandong 250000, China
| | - Yi Li
- Human Genetics, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Tiantian Du
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China.,Shandong Provincial Hospital for Skin Diseases, Shandong University, Jinan, Shandong 250000, China
| | - Wenjun Yu
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China.,Shandong Provincial Hospital for Skin Diseases, Shandong University, Jinan, Shandong 250000, China
| | - Yang Xia
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China.,Shandong Provincial Hospital for Skin Diseases, Shandong University, Jinan, Shandong 250000, China
| | - Hailu Xiao
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China
| | - Jiabao You
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China
| | - Jinghui Li
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China
| | - Qing Yang
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Hospital for Skin Diseases, Shandong University, Jinan, Shandong 250000, China
| | - Na Wang
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China.,School of Medicine, Shandong University, Jinan, Shandong 250000, China
| | - Panpan Shang
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China
| | - Guiye Niu
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China
| | - Xiaojun Chi
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China.,Shandong Provincial Hospital for Skin Diseases, Shandong University, Jinan, Shandong 250000, China
| | - Xiuhuan Wang
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China.,Shandong Provincial Hospital for Skin Diseases, Shandong University, Jinan, Shandong 250000, China
| | - Jing Cao
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China.,School of Medicine, Shandong University, Jinan, Shandong 250000, China
| | - Xiujun Cheng
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China.,School of Medicine, Shandong University, Jinan, Shandong 250000, China
| | - Hong Liu
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China.,Shandong Provincial Hospital for Skin Diseases, Shandong University, Jinan, Shandong 250000, China
| | - Jianjun Liu
- Human Genetics, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Furen Zhang
- Shandong Provincial Institute of Dermatology and Venereology, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, China.,Shandong Provincial Key Laboratory for Dermatovenereology, Jinan, Shandong 250000, China.,School of Medicine, Shandong University, Jinan, Shandong 250000, China.,School of Medicine and Life Science, University of Jinan-Shandong Academy of Medical Sciences, Jinan, Shandong 250022, China.,Shandong Provincial Hospital for Skin Diseases, Shandong University, Jinan, Shandong 250000, China.,National Clinical Key Project of Dermatology and Venereology, Jinan, Shandong 250000, China
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10
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Oliveira JM, Rêgo JL, de Lima Santana N, Braz M, Jamieson SE, Vieira TS, Magalhães TL, Machado PRL, Blackwell JM, Castellucci LC. The -308 bp TNF gene polymorphism influences tumor necrosis factor expression in leprosy patients in Bahia State, Brazil. INFECTION GENETICS AND EVOLUTION 2016; 39:147-154. [PMID: 26829382 DOI: 10.1016/j.meegid.2016.01.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Revised: 01/27/2016] [Accepted: 01/28/2016] [Indexed: 02/04/2023]
Abstract
Leprosy or Hansen's disease is a debilitating chronic granulomatous disease caused by Mycobacterium leprae, with high incidence and prevalence in Brazil. The -308 bp G/A single nucleotide polymorphism (SNP rs1800629) in the tumor necrosis factor (TNF) gene promoter is a proposed risk factor for leprosy. In Brazil, Northern India, Egypt and Nepal, the common G allele was associated with leprosy. In Eastern India, Thailand and Malawi the minor A allele was the risk factor. Allele A was previously associated with high TNF. We genotyped rs1800629 in 326 leprosy cases from Bahia State, Brazil, including 72 paucibacillary (PB) and 47 multibacillary (MB) without reactions, and 69 reversal reaction (RR) and 78 erythema nodosum leprosum (ENL) with reactions. Logistic regression was used to compare patient groups with 331 healthy controls. Relative TNF mRNA was determined in peripheral blood leukocytes by QRTPCR, and serum TNF levels measured by ELISA. We found that TNF mRNA expression was higher (P=0.03) in leprosy patients compared to endemic controls, but did not differ significantly between clinical subgroups. Carriage of the minor A allele was associated (P=0.003) with low TNF mRNA across leprosy patients. Nevertheless, we found no evidence for either allele at this SNP as a risk factor for leprosy per se (OR=1.12, 95% CI 0.79-1.60, P=0.52), PB (OR=0.99, 95% CI 0.54-1.81, P=0.97), MB (OR=0.86, 95% CI 0.40-1.83, P=0.70), RR (OR=1.37, 95% CI 0.79-2.38, P=0.27) or ENL (OR=0.76, 95% CI 0.40-1.45, P=0.42) when compared to endemic controls. Further studies are required to determine whether the influence of the minor A allele on TNF mRNA levels determines response to treatment, particularly in the context of ENL reaction treatment with anti-TNF therapies and RR reactions where treatment with prednisolone is known to reduce TNF levels. Our findings contribute to understanding TNF as an important determinant of leprosy immunopathology in Brazil.
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Affiliation(s)
- Joyce Moura Oliveira
- National Institute of Science and Technology in Tropical Diseases, Brazil and Federal University of Bahia, Salvador, Brazil; Program of Post-graduation in Health Sciences, Federal University of Bahia, Salvador, Brazil.
| | - Jamile Leão Rêgo
- National Institute of Science and Technology in Tropical Diseases, Brazil and Federal University of Bahia, Salvador, Brazil; Program of Post-graduation in Health Sciences, Federal University of Bahia, Salvador, Brazil.
| | - Nadja de Lima Santana
- National Institute of Science and Technology in Tropical Diseases, Brazil and Federal University of Bahia, Salvador, Brazil; Program of Post-graduation in Health Sciences, Federal University of Bahia, Salvador, Brazil.
| | - Marcos Braz
- National Institute of Science and Technology in Tropical Diseases, Brazil and Federal University of Bahia, Salvador, Brazil; Program of Post-graduation in Health Sciences, Federal University of Bahia, Salvador, Brazil.
| | - Sarra E Jamieson
- Telethon Kids Institute, The University of Western Australia, Subiaco, Western Australia, Australia.
| | - Thaillamar Silva Vieira
- National Institute of Science and Technology in Tropical Diseases, Brazil and Federal University of Bahia, Salvador, Brazil.
| | - Thaís Lamêgo Magalhães
- National Institute of Science and Technology in Tropical Diseases, Brazil and Federal University of Bahia, Salvador, Brazil.
| | - Paulo Roberto Lima Machado
- National Institute of Science and Technology in Tropical Diseases, Brazil and Federal University of Bahia, Salvador, Brazil; Program of Post-graduation in Health Sciences, Federal University of Bahia, Salvador, Brazil.
| | - Jenefer M Blackwell
- Telethon Kids Institute, The University of Western Australia, Subiaco, Western Australia, Australia.
| | - Léa C Castellucci
- National Institute of Science and Technology in Tropical Diseases, Brazil and Federal University of Bahia, Salvador, Brazil; Program of Post-graduation in Health Sciences, Federal University of Bahia, Salvador, Brazil.
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11
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Kubanov AA, Karamova AE, Vorontsova AA, Kalinina PA. Experimental models of leprosy. VESTNIK DERMATOLOGII I VENEROLOGII 2015. [DOI: 10.25208/0042-4609-2015-91-6-17-29] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Abstract
Leprosy (Hansen’s disease) is a chronic granulomatous bacterial disease which mainly affects skin and peripheral nervous system. Leprosy is caused by the obligate intercellular pathogen known as Mycobacterium leprae. Creating experimental models of leprosy is associated with serious problems due to biological characteristics of the pathogen. Numerous attempts to develop experimental models on different types of animals resulted in a few reproducible models on mice and nine-banded armadillos. Strains of knockout mice with genetic defects caused by site-directed mutagenesis are used as a basis for different leprosy models. Experimental models of leprosy are used for screening of anti-leprosy drugs, detection of drug resistance, studies on the pathogenesis of leprosy, production and evaluation of viability of M. leprae, developing of anti-leprosy vaccines.
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12
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Sauer MED, Salomão H, Ramos GB, D'Espindula HRS, Rodrigues RSA, Macedo WC, Sindeaux RHM, Mira MT. Genetics of leprosy: Expected-and unexpected-developments and perspectives. Clin Dermatol 2015; 34:96-104. [PMID: 26773629 DOI: 10.1016/j.clindermatol.2015.10.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
A solid body of evidence produced over decades of intense research supports the hypothesis that leprosy phenotypes are largely dependent on the genetic characteristics of the host. The early evidence of a major gene effect controlling susceptibility to leprosy came from studies of familial aggregation, twins, and complex segregation analysis. Later, linkage and association analysis, first applied to the investigation of candidate genes and chromosomal regions and more recently, to genome-wide scans, have revealed several HLA and non-HLA gene variants as risk factors for leprosy phenotypes such as disease per se, its clinical forms, and leprosy reactions. In addition, powerful, hypothesis-free strategies such as genome-wide association studies have led to an exciting, unexpected development: Leprosy susceptibility genes seem to be shared with Crohn's and Parkinson's disease. Today, a major challenge is to find the exact variants causing the biological effect underlying the genetic associations. New technologies, such as Next Generation Sequencing-that allows, for the first time, the cost- and time-effective sequencing of a complete human genome-hold the promise to reveal such variants; thus, strategies can be developed to study the functional impact of these variants in the context of infection, hopefully leading to the development of new targets for leprosy treatment and prevention.
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Affiliation(s)
- Monica E D Sauer
- Group for Advanced Molecular Investigation, Graduate Program in Health Sciences, School of Medicine, Pontifical Catholic University of Paraná, Curitiba, Paraná, Brazil
| | - Heloisa Salomão
- Group for Advanced Molecular Investigation, Graduate Program in Health Sciences, School of Medicine, Pontifical Catholic University of Paraná, Curitiba, Paraná, Brazil
| | - Geovana B Ramos
- Group for Advanced Molecular Investigation, Graduate Program in Health Sciences, School of Medicine, Pontifical Catholic University of Paraná, Curitiba, Paraná, Brazil
| | - Helena R S D'Espindula
- Group for Advanced Molecular Investigation, Graduate Program in Health Sciences, School of Medicine, Pontifical Catholic University of Paraná, Curitiba, Paraná, Brazil
| | - Rafael S A Rodrigues
- Group for Advanced Molecular Investigation, Graduate Program in Health Sciences, School of Medicine, Pontifical Catholic University of Paraná, Curitiba, Paraná, Brazil
| | - Wilian C Macedo
- Group for Advanced Molecular Investigation, Graduate Program in Health Sciences, School of Medicine, Pontifical Catholic University of Paraná, Curitiba, Paraná, Brazil
| | - Renata H M Sindeaux
- School of Health and Biological Sciences, Pontifical Catholic University of Paraná, Curitiba, Paraná, Brazil
| | - Marcelo T Mira
- Group for Advanced Molecular Investigation, Graduate Program in Health Sciences, School of Medicine, Pontifical Catholic University of Paraná, Curitiba, Paraná, Brazil; School of Health and Biological Sciences, Pontifical Catholic University of Paraná, Curitiba, Paraná, Brazil.
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13
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Sauer MED, Salomão H, Ramos GB, D'Espindula HRS, Rodrigues RSA, Macedo WC, Sindeaux RHM, Mira MT. Genetics of leprosy: expected and unexpected developments and perspectives. Clin Dermatol 2015; 33:99-107. [PMID: 25432815 DOI: 10.1016/j.clindermatol.2014.10.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A solid body of evidence produced over decades of intense research supports the hypothesis that leprosy phenotypes are largely dependent on the genetic characteristics of the host. The early evidence of a major gene effect controlling susceptibility to leprosy came from studies of familial aggregation, twins, and Complex Segregation Analysis. Later, linkage and association analysis, first applied to the investigation of candidate genes and chromosomal regions and more recently, to genome-wide scans, have revealed several leukocyte antigen complex and nonleukocyte antigen complex gene variants as risk factors for leprosy phenotypes such as disease per se, its clinical forms and leprosy reactions. In addition, powerful, hypothesis-free strategies such as Genome-Wide Association Studies have led to an exciting, unexpected development: Leprosy susceptibility genes seem to be shared with Crohn's and Parkinson's diseases. Today, a major challenge is to find the exact variants causing the biological effect underlying the genetic associations. New technologies, such as Next Generation Sequencing that allows, for the first time, the cost and time-effective sequencing of a complete human genome, hold the promise to reveal such variants. Strategies can be developed to study the functional effect of these variants in the context of infection, hopefully leading to the development of new targets for leprosy treatment and prevention.
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Affiliation(s)
- Monica E D Sauer
- Group for Advanced Molecular Investigation, Graduate Program in Health Sciences, School of Medicine, Pontifical Catholic University of Paraná, Curitiba, Paraná, Brazil
| | - Heloisa Salomão
- Group for Advanced Molecular Investigation, Graduate Program in Health Sciences, School of Medicine, Pontifical Catholic University of Paraná, Curitiba, Paraná, Brazil
| | - Geovana B Ramos
- Group for Advanced Molecular Investigation, Graduate Program in Health Sciences, School of Medicine, Pontifical Catholic University of Paraná, Curitiba, Paraná, Brazil
| | - Helena R S D'Espindula
- Group for Advanced Molecular Investigation, Graduate Program in Health Sciences, School of Medicine, Pontifical Catholic University of Paraná, Curitiba, Paraná, Brazil
| | - Rafael S A Rodrigues
- Group for Advanced Molecular Investigation, Graduate Program in Health Sciences, School of Medicine, Pontifical Catholic University of Paraná, Curitiba, Paraná, Brazil
| | - Wilian C Macedo
- Group for Advanced Molecular Investigation, Graduate Program in Health Sciences, School of Medicine, Pontifical Catholic University of Paraná, Curitiba, Paraná, Brazil
| | - Renata H M Sindeaux
- School of Health and Biological Sciences, Pontifical Catholic University of Paraná, Curitiba, Paraná, Brazil
| | - Marcelo T Mira
- Group for Advanced Molecular Investigation, Graduate Program in Health Sciences, School of Medicine, Pontifical Catholic University of Paraná, Curitiba, Paraná, Brazil; School of Health and Biological Sciences, Pontifical Catholic University of Paraná, Curitiba, Paraná, Brazil.
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14
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Silva GAV, Ramasawmy R, Boechat AL, Morais AC, Carvalho BKS, Sousa KBA, Souza VC, Cunha MGS, Barletta-Naveca RH, Santos MP, Naveca FG. Association of TNF -1031 C/C as a potential protection marker for leprosy development in Amazonas state patients, Brazil. Hum Immunol 2015; 76:137-41. [PMID: 25636570 DOI: 10.1016/j.humimm.2015.01.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Revised: 12/26/2014] [Accepted: 01/14/2015] [Indexed: 12/30/2022]
Abstract
Polymorphisms present in the TNF promoter region has shown to influence the gene transcription. Leprosy displays different clinical manifestations according to the immune responses of the individual infected with Mycobacterium leprae. In this study, we evaluated the single nucleotide polymorphisms (SNPs) -238 G/A (rs361525), -308 G/A (rs1800629), -857 C/T (rs1799724), -863 A/C (rs1800630) and -1031 T/C (rs1799964) in the promoter region of the TNF to see whether these SNPs influence host-susceptibility to leprosy and the different clinical manifestation. Nucleotide sequencing was performed with DNA samples from 108 leprosy patients and 253 control subjects. An association between -1031 C/C genotype and protection from leprosy was observed when leprosy patients were compared to controls (OR 0.11; 95% CI=0.01-0.82; p=0.012). The -857 C/T genotype may be associated with susceptibility to leprosy (OR=1.81; 95% CI=1.09-3.00; p=0.028). Similar genotype and allele frequencies for the SNPs -308 G/A and -238 G/A were observed between leprosy patients and control subjects. Altogether, TNF polymorphisms in the promoter region may be predictive of leprosy outcome.
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Affiliation(s)
- G A V Silva
- Instituto Leônidas e Maria Deane, FIOCRUZ Amazônia, Manaus, Amazonas, Brazil.
| | - R Ramasawmy
- Fundação de Medicina Tropical Doutor Heitor Vieira Dourado, Manaus, Amazonas, Brazil; Faculdade de Medicina, Universidade Nilton Lins, Manaus, Amazonas, Brazil
| | - A L Boechat
- Laboratório de Imunologia, Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal do Amazonas, Manaus, Brazil
| | - A C Morais
- Instituto Leônidas e Maria Deane, FIOCRUZ Amazônia, Manaus, Amazonas, Brazil
| | - B K S Carvalho
- Instituto Leônidas e Maria Deane, FIOCRUZ Amazônia, Manaus, Amazonas, Brazil
| | - K B A Sousa
- Instituto Leônidas e Maria Deane, FIOCRUZ Amazônia, Manaus, Amazonas, Brazil
| | - V C Souza
- Instituto Leônidas e Maria Deane, FIOCRUZ Amazônia, Manaus, Amazonas, Brazil
| | - M G S Cunha
- Fundação de Dermatologia e Venereologia Alfredo da Matta, Manaus, Amazonas, Brazil
| | - R H Barletta-Naveca
- Laboratório de Micobacteriologia, Instituto Nacional de Pesquisas da Amazônia, Manaus, Amazonas, Brazil
| | - M P Santos
- Laboratório de Micobacteriologia, Instituto Nacional de Pesquisas da Amazônia, Manaus, Amazonas, Brazil
| | - F G Naveca
- Instituto Leônidas e Maria Deane, FIOCRUZ Amazônia, Manaus, Amazonas, Brazil
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15
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IL-10 and NOS2 modulate antigen-specific reactivity and nerve infiltration by T cells in experimental leprosy. PLoS Negl Trop Dis 2014; 8:e3149. [PMID: 25210773 PMCID: PMC4161319 DOI: 10.1371/journal.pntd.0003149] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Accepted: 07/28/2014] [Indexed: 12/18/2022] Open
Abstract
Background Although immunopathology dictates clinical outcome in leprosy, the dynamics of early and chronic infection are poorly defined. In the tuberculoid region of the spectrum, Mycobacterium leprae growth is restricted yet a severe granulomatous lesion can occur. The evolution and maintenance of chronic inflammatory processes like those observed in the leprosy granuloma involve an ongoing network of communications via cytokines. IL-10 has immunosuppressive properties and IL-10 genetic variants have been associated with leprosy development and reactions. Methodology/Principal Findings The role of IL-10 in resistance and inflammation in leprosy was investigated using Mycobacterium leprae infection of mice deficient in IL-10 (IL-10−/−), as well as mice deficient in both inducible nitric oxide synthase (NOS2−/−) and IL-10 (10NOS2−/−). Although a lack of IL-10 did not affect M. leprae multiplication in the footpads (FP), inflammation increased from C57Bl/6 (B6)<IL-10−/−<NOS2−/−<10NOS2−/−. While IL-10−/− mice exhibited modest FP induration compared to B6, NOS2−/− and 10NOS2−/− mice developed markedly enlarged FP marking distinct phases: early (1 month), peak (3–4 months), and chronic (8 months). IFN-γ-producing CD4+CD44+ cells responding to M. leprae cell wall, membrane, and cytosol antigens and ML2028 (Ag85B) were significantly increased in the evolved granuloma in NOS2−/− FP compared to B6 and IL-10−/− during early and peak phases. In 10NOS2−/− FP, CD4+CD44+ and especially CD8+CD44+ responses were augmented even further to these antigens as well as to ML0380 (GroES), ML2038 (bacterioferritin), and ML1877 (EF-Tu). Moreover, fragmented nerves containing CD4+ cells were present in 10NOS2−/− FP. Conclusions/Significance The 10NOS2−/− strain offers insight on the regulation of granuloma formation and maintenance by immune modulators in the resistant forms of leprosy and presents a new model for investigating the pathogenesis of neurological involvement. Despite effective antimicrobial therapy, 30–50% of leprosy patients develop immunological complications called leprosy reactions before, during or even years after being cured. Leprosy reactions are a major risk for neuritis that leads to peripheral nerve damage, disfigurement and disability. Unfortunately, why and how leprosy reactions occur is not well understood. Based on the latest human genetic leprosy susceptibility research and mouse infection models, we generated a double knockout mouse strain (10NOS2−/−) which has deficiencies in two key immune factors, interleukin-10 (IL-10) and inducible nitric oxide synthase (NOS2). We investigated the dynamics of the immune response to Mycobacterium leprae infection and chronicled the types of immune cells recruited to the site of infection. 10NOS2−/− mice developed a substantial induration in response to infection, as well as an increased interferon-gamma response to components of the leprosy bacillus. Interestingly, these animals also exhibited CD4+ T cell infiltration into the nerves, a phenomenon which has not been previously reported in leprosy mouse models. This new model provides insight into potential mechanisms whereby immune modulators may regulate leprosy reactions and neuritis and could aid the development of tests for monitoring and treatment of leprosy patients.
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16
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Adams LB, Pena MT, Sharma R, Hagge DA, Schurr E, Truman RW. Insights from animal models on the immunogenetics of leprosy: a review. Mem Inst Oswaldo Cruz 2013; 107 Suppl 1:197-208. [PMID: 23283472 DOI: 10.1590/s0074-02762012000900028] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Accepted: 06/05/2012] [Indexed: 11/21/2022] Open
Abstract
A variety of host immunogenetic factors appear to influence both an individual's susceptibility to infection with Mycobacterium leprae and the pathologic course of the disease. Animal models can contribute to a better understanding of the role of immunogenetics in leprosy through comparative studies helping to confirm the significance of various identified traits and in deciphering the underlying mechanisms that may be involved in expression of different disease related phenotypes. Genetically engineered mice, with specific immune or biochemical pathway defects, are particularly useful for investigating granuloma formation and resistance to infection and are shedding new light on borderline areas of the leprosy spectrum which are clinically unstable and have a tendency toward immunological complications. Though armadillos are less developed in this regard, these animals are the only other natural hosts of M. leprae and they present a unique opportunity for comparative study of genetic markers and mechanisms associable with disease susceptibility or resistance, especially the neurological aspects of leprosy. In this paper, we review the recent contributions of genetically engineered mice and armadillos toward our understanding of the immunogenetics of leprosy.
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Affiliation(s)
- Linda B Adams
- Department of Health and Human Services, Health Resources and Services Administration, Bureau of Primary Health Care, National Hansen's Disease Programs, Baton Rouge, LA, USA.
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Guerreiro LTA, Robottom-Ferreira AB, Ribeiro-Alves M, Toledo-Pinto TG, Rosa Brito T, Rosa PS, Sandoval FG, Jardim MR, Antunes SG, Shannon EJ, Sarno EN, Pessolani MCV, Williams DL, Moraes MO. Gene expression profiling specifies chemokine, mitochondrial and lipid metabolism signatures in leprosy. PLoS One 2013; 8:e64748. [PMID: 23798993 PMCID: PMC3683049 DOI: 10.1371/journal.pone.0064748] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 04/16/2013] [Indexed: 11/18/2022] Open
Abstract
Herein, we performed microarray experiments in Schwann cells infected with live M. leprae and identified novel differentially expressed genes (DEG) in M. leprae infected cells. Also, we selected candidate genes associated or implicated with leprosy in genetic studies and biological experiments. Forty-seven genes were selected for validation in two independent types of samples by multiplex qPCR. First, an in vitro model using THP-1 cells was infected with live Mycobacterium leprae and M. bovis bacillus Calmette-Guérin (BCG). In a second situation, mRNA obtained from nerve biopsies from patients with leprosy or other peripheral neuropathies was tested. We detected DEGs that discriminate M. bovis BCG from M. leprae infection. Specific signatures of susceptible responses after M. leprae infection when compared to BCG lead to repression of genes, including CCL2, CCL3, IL8 and SOD2. The same 47-gene set was screened in nerve biopsies, which corroborated the down-regulation of CCL2 and CCL3 in leprosy, but also evidenced the down-regulation of genes involved in mitochondrial metabolism, and the up-regulation of genes involved in lipid metabolism and ubiquitination. Finally, a gene expression signature from DEG was identified in patients confirmed of having leprosy. A classification tree was able to ascertain 80% of the cases as leprosy or non-leprous peripheral neuropathy based on the expression of only LDLR and CCL4. A general immune and mitochondrial hypo-responsive state occurs in response to M. leprae infection. Also, the most important genes and pathways have been highlighted providing new tools for early diagnosis and treatment of leprosy.
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Affiliation(s)
| | | | - Marcelo Ribeiro-Alves
- Laboratório de Hanseníase, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, FIOCRUZ-RJ, Rio de Janeiro, Brazil
- Laboratório de Pesquisa em Farmacogenética, Instituto de Pesquisa Clínica Evandro Chagas (IPEC), FIOCRUZ-RJ, Rio de Janeiro, Brazil
| | - Thiago Gomes Toledo-Pinto
- Laboratório de Hanseníase, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, FIOCRUZ-RJ, Rio de Janeiro, Brazil
| | - Tiana Rosa Brito
- Laboratório de Hanseníase, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, FIOCRUZ-RJ, Rio de Janeiro, Brazil
| | | | - Felipe Galvan Sandoval
- Health Resources and Services Administration (HRSA), Bureau of Primary Health Care (BPHC), Division of National Hansen's Disease Programs, Laboratory Research Branch at the School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, United States of America
| | - Márcia Rodrigues Jardim
- Laboratório de Hanseníase, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, FIOCRUZ-RJ, Rio de Janeiro, Brazil
| | - Sérgio Gomes Antunes
- Laboratório de Hanseníase, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, FIOCRUZ-RJ, Rio de Janeiro, Brazil
| | - Edward J. Shannon
- Health Resources and Services Administration (HRSA), Bureau of Primary Health Care (BPHC), Division of National Hansen's Disease Programs, Laboratory Research Branch at the School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, United States of America
| | - Euzenir Nunes Sarno
- Laboratório de Hanseníase, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, FIOCRUZ-RJ, Rio de Janeiro, Brazil
| | | | - Diana Lynn Williams
- Health Resources and Services Administration (HRSA), Bureau of Primary Health Care (BPHC), Division of National Hansen's Disease Programs, Laboratory Research Branch at the School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, United States of America
| | - Milton Ozório Moraes
- Laboratório de Hanseníase, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, FIOCRUZ-RJ, Rio de Janeiro, Brazil
- * E-mail:
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Cardoso CC, Pereira AC, Brito-de-Souza VN, Duraes SMB, Ribeiro-Alves M, Nery JAC, Francio ÂS, Vanderborght PR, Parelli FPC, Alter A, Salgado JL, Sampaio EP, Santos AR, Oliveira MLWR, Sarno EN, Schurr E, Mira MT, Pacheco AG, Moraes MO. TNF -308G>A single nucleotide polymorphism is associated with leprosy among Brazilians: a genetic epidemiology assessment, meta-analysis, and functional study. J Infect Dis 2011; 204:1256-63. [PMID: 21917899 DOI: 10.1093/infdis/jir521] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Leprosy is an infectious disease caused by Mycobacterium leprae. Tumor necrosis factor (TNF) plays a key role in the host response. Some association studies have implicated the single nucleotide polymorphism TNF -308G>A in leprosy susceptibility, but these results are still controversial. We first conducted 4 association studies (2639 individuals) that showed a protective effect of the -308A allele (odds ratio [OR] = 0.77; P = .005). Next, results of a meta-analysis reinforced this association after inclusion of our new data (OR = 0.74; P = .04). Furthermore, a subgroup analysis including only Brazilian studies suggested that the association is specific to this population (OR = 0.63; P = .005). Finally, functional analyses using whole blood cultures showed that patients carrying the -308A allele produced higher TNF levels after lipopolysaccharide (LPS) (6 hours) and M. leprae (3 hours) stimulation. These results reinforce the association between TNF and leprosy and suggest the -308A allele as a marker of disease resistance, especially among Brazilians.
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Affiliation(s)
- Cynthia C Cardoso
- Laboratório de Hanseníase, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, Brazil
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Cardoso CC, Pereira AC, de Sales Marques C, Moraes MO. Leprosy susceptibility: genetic variations regulate innate and adaptive immunity, and disease outcome. Future Microbiol 2011; 6:533-49. [PMID: 21585261 DOI: 10.2217/fmb.11.39] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The past few years have been very productive concerning the identification of genes associated with leprosy. Candidate gene strategies using both case-control and family-based designs, as well as large-scale approaches such as linkage and gene-expression genomic scans and, more recently, genome-wide association studies, have refined and enriched the list of genes highlighting the most important innate and adaptive immune pathways associated with leprosy susceptibility or resistance. During the early events of host-pathogen interaction identified genes are involved in pattern recognition receptors, and mycobacterial uptake (TLRs, NOD2 and MRC1), which modulate autophagy. Another gene, LTA4H, which regulates the levels of lipoxin A4 and possibly interacts with lipid droplet-related events, also plays a role in the early immune responses to Mycobacterium leprae. Together, the activation of these pathways regulates cellular metabolism upon infection, activating cytokine production through NF-κB and vitamin D-vitamin D receptor pathways, while PARK2 and LRRK2 participate in the regulation of host-cell apoptosis. Concomitantly, genes triggered to form and maintain granulomas (TNF, LTA and IFNG) and genes involved in activating and differentiating T-helper cells (HLA, IL10, as well as the TNF/LTA axis and the IFNG/IL12 axis) bridge immunological regulation towards adaptive immunity. Subtle variations in these genes, mostly single nucleotide polymorphisms, alter the risk of developing the disease or the severity of leprosy. Knowing these genes and their role will ultimately lead to better strategies for leprosy prevention, treatment and early diagnosis. Finally, the same genes associated with leprosy were also associated with autoimmune (Crohn's disease, rheumathoid arthritis, psoriasis) or neurodegenerative diseases (Parkinson's and Alzheimer's). Thus, information retrieved using leprosy as a model could be valuable to understanding the pathogenesis of other complex diseases.
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Simon M, Scherlock J, Duthie MS, Ribeiro de Jesus A. Clinical, immunological, and genetic aspects in leprosy. Drug Dev Res 2011. [DOI: 10.1002/ddr.20457] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Souza-Lemos C, de-Campos SN, Teva A, Porrozzi R, Grimaldi Jr G. In situ characterization of the granulomatous immune response with time in nonhealing lesional skin of Leishmania braziliensis-infected rhesus macaques (Macaca mulatta). Vet Immunol Immunopathol 2011; 142:147-55. [DOI: 10.1016/j.vetimm.2011.05.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2011] [Revised: 04/07/2011] [Accepted: 05/02/2011] [Indexed: 10/18/2022]
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Abstract
An animal model of granulomatous hypersensitivity has been developed, which reproduces some features of the pathologies of important chronic granulomatous disorders, including tuberculosis, tuberculoid leprosy, sarcoidosis, berylliosis, Crohn's disease, and sensitivity to zirconium. The lesions consist of focal collections of epithelioid cells surrounded by lymphocytes to form tubercles. The epithelioid cell has a secretory function and is not phagocytic. Plasmacytoid dendritic cells are precursors of epithelioid cells, which are therefore part of the innate immune system. Subplasmalemmal linear densities are also present in these cells. This autoimmune model has been induced in rabbits using a non-myelin sensory peripheral antigen to reproduce the features of tuberculoid leprosy. The antigen is probably present only in human tissue. A granuloma antigen, which is tissue specific similar to that in peripheral nerves, could be present in sarcoidosis and Crohn's disease. In multiple sclerosis, mononuclear cells in the brain parenchyma are not phagocytic and are therefore similar to epithelioid cells. The induction of tolerance leading to the development of a vaccine to prevent the lesions in multiple sclerosis, sarcoidosis, and Crohn's disease is possible after purification of the granuloma antigen.
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Affiliation(s)
- Colin L Crawford
- Imperial College of Medicine, Charing Cross Hospital, London, UK.
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Abstract
Cells of the innate immune system produce cytokines and lipid mediators that strongly influence the outcome of mycobacterial infection. In the case of Mycobacterium tuberculosis, the lung is a critical site for this interaction. Here, we review current information on the role of the major innate cytokine pathways both in controlling initial infection as well as in promoting and maintaining adaptive T-cell responses that mediate host resistance or immunopathology. Understanding this important feature of the host-pathogen interaction can provide major insights into the mechanisms of virulence and can lead to new approaches for immunological intervention in tuberculosis and other mycobacterial diseases.
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Affiliation(s)
| | | | - Alan Sher
- Immunobiology Section, Laboratory of Parasitic Diseases, NIAID, NIH, Bethesda, MD 20892
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Abstract
Despite the availability of effective treatment for several decades, leprosy remains an important medical problem in many regions of the world. Infection with Mycobacterium leprae can produce paucibacillary disease, characterized by well-formed granulomas and a Th1 T-cell response, or multibacillary disease, characterized by poorly organized cellular infiltrates and Th2 cytokines. These diametric immune responses confer states of relative resistance or susceptibility to leprosy, respectively, and have well-defined clinical manifestations. As a result, leprosy provides a unique opportunity to dissect the genetic basis of human in vivo immunity. A series of studies over the past 40 years suggests that host genes influence the risk of leprosy acquisition and the predilection for different clinical forms of the disease. However, a comprehensive, cellular, and molecular view of the genes and variants involved is still being assembled. In this article, we review several decades of human genetic studies of leprosy, including a number of recent investigations. We emphasize genetic analyses that are validated by the replication of the same phenotype in independent studies or supported by functional experiments demonstrating biological mechanisms of action for specific polymorphisms. Identifying and functionally exploring the genetic and immunological factors that underlie human susceptibility to leprosy have yielded important insights into M. leprae pathogenesis and are likely to advance our understanding of the immune response to other pathogenic mycobacteria. This knowledge may inform new treatment or vaccine strategies for leprosy or tuberculosis.
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