American Cutaneous Leishmaniasis: In Situ Characterization of the Cellular Immune Response with Time

Lima, Hermenio; Vasconcelos, A. W.; David, John R.; Lerner, Ethan A.

doi:10.4269/ajtmh.1994.50.743

Cited by 37 publications

(44 citation statements)

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“…The percentage of cells in the granulomas expressing the MHC class II antigens (HLA-DR+) in active lesions (95 ± 7.1%) was significantly higher (P < 0.005) from the healing lesions (42 ± 12.7%) (Amaral et al 2000). Results similar to ours were previously reported, studying the infiltrate in the skin of humans with CL , Lima et al 1994.…”

Section: Discussionsupporting

confidence: 89%

Leishmania (Leishmania) major-infected rhesus macaques (Macaca mulatta) develop varying levels of resistance against homologous re-infections

Têva

Porrozzi

et al. 2001

Mem. Inst. Oswaldo Cruz

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Section: Discussionsupporting

confidence: 89%

Leishmania (Leishmania) major-infected rhesus macaques (Macaca mulatta) develop varying levels of resistance against homologous re-infections

Têva

Porrozzi

et al. 2001

Mem. Inst. Oswaldo Cruz

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“…Instead, peripheral blood ␥␦ T cells are formidably equipped for instant relocation to inflammatory processes, which explains their early accumulation at sites of microbial infection. 56,57 Low numbers of peripheral blood ␥␦ T cells express CCR7 and bear signs of preactivation, suggesting that they reflect ongoing immune activities (not shown).…”

Section: Discussionmentioning

confidence: 99%

“…In support, ␥␦ T cells were found early at sites of infection, and their numbers decreased during disease progression. 56,57 Thus, ␥␦ T cells may influence the subsequent adaptive immune responses through interaction with peripheral DCs and B cells in reactive secondary lymphoid tissues. The rapid activationdependent switch in homing characteristics provides new important insights into the role of ␥␦ T cells in antimicrobial immune responses and clearly puts them apart from any other type of innate cells.…”

Section: Discussionmentioning

confidence: 99%

Flexible migration program regulates γδ T-cell involvement in humoral immunity

Brandes

Willimann

Lang

et al. 2003

Blood

154

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IntroductionThe extraordinary conservation of the subset of T cells expressing V␥V␦-T-cell receptors (TCRs) suggests a nonredundant but still poorly understood role in immune defense. [1][2][3][4][5] The 2 major ␥␦ T-cell subsets in human beings, defined by TCRs containing V␦1 or V␦2 chains, differ in their anatomic localization; V␦1 ϩ T cells predominate within mucosal epithelia and skin whereas V␦2 ϩ T cells are most numerous in peripheral blood. A function in antimicrobial immunity is supported by the dramatic expansion of human ␥␦ T cells in response to a wide range of pathogens and by reduced ␥␦ T-cell numbers and function during disease progression. 4,5 Infectious disease models demonstrated a 2-stage involvement of ␥␦ T cells, the first taking place during the innate phase of primary immune responses and the second being effective during wound repair after pathogen elimination. 4,5 Recently, ␥␦ T cells were postulated to contribute also to memory responses against mycobacteria. 6 Lysates from a large variety of bacteria, parasites, and plants were shown to induce oligoclonal expansion of human V␦2 ϩ T cells in vitro. 3,4 However, ␥␦ T cells differ fundamentally from ␣␤ T cells in the types of antigens (Ags) they recognize. Human ␥␦ T cells recognize small molecular weight nonpeptide Ags, stress-or tumor-induced self Ags, and the CD1 nonpolymorphic lipid Ag-presenting molecules. 3,4,7 The principal pathogen-derived ␥␦ T-cell Ags are isopentenyl pyrophosphate (IPP) and one of its metabolic precursors, (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMBPP). [8][9][10] The "simple" mode of Ag recognition (apparent lack of requirement for Ag processing and major histocompatibility complex [MHC] restriction) and the chemical nature of these essential pathogen-specific metabolites suggest a "pattern recognition" type of Ag selectivity by human V␦2 ϩ T cells. 3,4,9 CD1-restricted Ag recognition mainly involves V␦1-TCRs and appears to participate in self-recognition of nonpolymorphic CD1 that may contribute to dendritic cell (DC) maturation 11 (M.B.B. and D. Leslie, personal written communication, July 2002).Responsiveness to microbial metabolic intermediates points to an immediate (as opposed to proliferation/differentiation-dependent) involvement of ␥␦ T cells in antimicrobial processes. Therefore, the migration properties of ␥␦ T cells may resemble those of monocytes and granulocytes that appear early at sites of infection. Chemokines are best known for controlling leukocyte localization during hematopoiesis, initiation of immune responses, and inflammation. 12-14 Traffic patterns and the inflammatory function in leukocytes are largely defined by their chemokine receptor expression and migration profile. Chemokines are divided into 2 major subfamilies, the "homeostatic" and the "inflammatory" chemokines, and their distinctive roles are best exemplified in mature T cells. [14][15][16][17][18] The homeostatic chemokines SLC/CCL21 13 and ELC/CCL19 are constitutively produced in T zones of secondary lymphoid tis...

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“…On the other hand, the course of leishmaniasis in mice lacking beta 2-microglobulin (beta 2-m) gene did not differ from their wild-type counterparts (Overath & Harbecke 1993, Wang et al 1993, Huber et al 1998) lessening a role of antigen presentation by major histocompatibility complex class I (MHC I) molecules. In man, a higher percentage of CD8 + over CD4 + T cells was found in mucocutaneous leishmaniasis (MCL) lesions (Castes & Tapia 1998), compared to localized cutaneous lesions (LCL), although similar distributions of CD4 + and CD8 + in LCL have been reported (Barral et al 1987, Esterre et al 1992, Lima et al 1994. The presence of cytotoxic CD8 + T cells has been reported in peripheral blood of MCL but not in LCL patients (Brodskyn et al 1997).…”

mentioning

confidence: 95%

B-cell infiltration and frequency of cytokine producing cells differ between localized and disseminated human cutaneous leishmaniases

Vieira

Oliveira

Arruda

et al. 2002

Mem. Inst. Oswaldo Cruz

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Biopsies from human localized cutaneous lesions (LCL n = 7) or disseminated lesions (DL n = 8) cases were characterized according to cellular infiltration, frequency of cytokine (IFN-γ, TNF-α) Cutaneous leishmaniasis is a worldwide disease with severe deformating potential in new world. It affects preferentially young economically active patients representing a large burden to the public health system in developing countries. Protection against all forms of leishmaniasis is dependent on cell-mediated immunity (CMI), but the contribution of some cells and cytokines in human disease deserves further scrutiny.CD8 + T cells have been implicated in protection (Muller et al. 1991) being high IFN-γ producers in a murine model of leishmaniasis (Chan 1993). Their role seems to be more in the secondary than in the primary immune response (Muller et al. 1993(Muller et al. , 1994. On the other hand, the course of leishmaniasis in mice lacking beta 2-microglobulin (beta 2-m) gene did not differ from their wild-type counterparts (Overath & Harbecke 1993, Wang et al. 1993, Huber et al. 1998) lessening a role of antigen presentation by major histocompatibility complex class I (MHC I) molecules. In man, a higher percentage of CD8 + over CD4 + T cells was found in mucocutaneous leishmaniasis (MCL) lesions (Castes & Tapia 1998), compared to localized cutaneous lesions (LCL), although similar distributions of CD4 + and CD8 + in LCL have been reported (Barral et al. 1987, Esterre et al. 1992, Lima et al. 1994. The presence of cytotoxic CD8 + T cells has been reported in peripheral blood of MCL but not in LCL patients (Brodskyn et al. 1997). Expansion of CD8 + T cells occurs in the peripheral blood of individuals vaccinated against leishmaniasis (Mendonça et al. 1995, Gurunathan et al. 2000. Especially, the percentage of activated CD8 + T cells was higher in fast responding than in slow responding volunteers to vaccination (Pompeu et al. 2001).The role of B cells in leishmaniasis is also not clear. High antibody levels are present in the more severe clinical form of the cutaneous disease, namely diffuse cutaneous leishmaniasis (DCL) (Schurr et al. 1986, Mengistu et al. 1990), but B cell depletion does not alter the susceptibility or resistance pattern to Leishmania infection in mice (Babai et al. 1999, Brown & Reiner 1999. It seems that B cells are important to induce anti-Leishmania CD4 + Th1 cells and DTH reaction, in the resistant mouse strain, and take part in the humoral response development in susceptible animals (Scott & Farrell 1982, Scott et al. 1986).Predominance of Th1 cytokines like IFN-γ, IL-12, IL-2 and TNF-α over Th2 cytokines, IL-4, IL-5 IL-10 and TGF-β, is correlated in mice to the resistance profile against Leishmania infection (Belosevic et al. 1989, Chatelain et al. 1992, Lezama-Davila et al. 1992, Barral et al. 1993. Imunological studies in humans demonstrated a combination of Th1 and Th2 cytokines with predominance of Th1 in MCL, Th2 predominate in DCL and predominance of Th1 profile in LCL patients , Castes et...

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American Cutaneous Leishmaniasis: In Situ Characterization of the Cellular Immune Response with Time

Cited by 37 publications

References 0 publications

Leishmania (Leishmania) major-infected rhesus macaques (Macaca mulatta) develop varying levels of resistance against homologous re-infections

Leishmania (Leishmania) major-infected rhesus macaques (Macaca mulatta) develop varying levels of resistance against homologous re-infections

Flexible migration program regulates γδ T-cell involvement in humoral immunity

B-cell infiltration and frequency of cytokine producing cells differ between localized and disseminated human cutaneous leishmaniases

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