Protective and Pathologic T Cell Response in Cutaneous and Mucosal Leishmaniasis

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1 Protective and Pathologic T Cell Response in Cutaneous and Mucosal Leishmaniasis EDGAR M. CARVALHO Serviço de Imunologia Hospital Universitário Prof. Edgard Santos Universidade Federal da Bahia Salvador-Bahia-Brazil

2 Endemic Areas of Leishmaniasis

3 Clinical Forms of L.brasiliensis Infection Subclinical DTH (+) Cutaneous Leishmaniasis Disseminated Leishmaniasis Mucosal Leishmaniasis

4 Protective and Pathological T cell Response in Cutaneous and Mucosal Leishmaniasis To compare sistemic and lesion site immune response in cutaneous and mucosal leishmaniasis. To correlate immunological response with pathology in cutaneous and mucosal leishmaniasis. To evaluate the mechanisms involved in the exagerated immunologic response in cutaneous and mucosal leishmaniasis.

5 Cytokine Profile in Patients with Cutaneous Leishmaniasis IFN-γ and TNF-α (pg/ml) IL-10 and IL-5 (pg/ml) 0 IFN TNF IL-10 IL-5 0

6 Cytokine Profile in Patients with Mucosal Leishmaniasis IFN-γ and TNF- α (pg/ml) IFN-γ TNF-α IL-10 IL IL-10 and IL-5 (pg/ml)

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8 Macrophages are the Main Source of TNF-α in Cutaneous and Mucosal Lesions Clinical form Total TNF-alpha+ cells CD68+ CD68- % contribution of CD68+ cells CL 1144+/ / / /-13 ML 1354+/ / / /-13

9 High Numbers of Cells Expressing IL-10 in Both Cutaneous and Mucosal Lesions Clinical form Total CD68+ IL-10+ cells % contribution of CD68+ cells Commitment of CD68+ cells CL 2025+/ / / /- 16 ML / / / /- 4 * *ML > CL, p<0,05

10 Protective and Pathological T cell Response in Cutaneous and Mucosal Leishmaniasis To compare sistemic and lesion site immune response in cutaneous and mucosal leishmaniasis. To correlate immunological response with pathology in cutaneous and mucosal leishmaniasis. To evaluate the mechanisms involved in the exagerated immunologic response in cutaneous and mucosal leishmaniasis.

11 Evidence that Tissue Damage in Cutaneous and Mucosal Leishmaniasis is Due to Inflammatory Response Tissue damage is associated to lymphocyte and macrophage infiltrate and few parasites in tissue. Bitencourt 1991 Exagerated type 1 immune response is more evidenciated in mucosal than in cutaneous leishmaniasis patients. Bacellar,2002 Decreasing in IFN-γ and TNF-α levels follows successful therapy with antimony in mucosal leishmaniasis. Lessa,2002 Antimony therapy in the pre-ulcerative phase of the disease do not prevent ulcer development in cutaneous leishmaniasis. Machado 2003 Molecules that down modulate immune response associated with antimony cure refractory cutaneous and mucosal leishmaniasis. Almeida,1999; Lessa 2002

12 Antimony Therapy Previous to the Ulcerative Phase do not Prevent Ulcer Development in Cutaneous Leishmaniasis

13 Granulomatous Vasculitis in Cutaneous Leishmaniasis

14 Correlation between Immunological Response and Lesion Size in Cutaneous Leishmaniasis

15 inos Expression: Correlation with Tissue Inflammation in Cutaneous but not Mucosal Leishmaniasis Total Infiltrate Cutaneous R 2 = 0,847 p<0, inos + Total Infiltrate R 2 = 0,100 p<0,6 Mucosal inos Total IFN-gamma+ cells/field inos + Linear Fit R 2 = 0.75 P=0, inos + Total IFN-gamma+ cells/field5000 Linear Fit R 2 = P=0,75

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17 Protective and Pathological T cell Response in Cutaneous and Mucosal Leishmaniasis To compare sistemic and lesion site immune response in cutaneous and mucosal leishmaniasis. To correlate immunological response with pathology in cutaneous and mucosal leishmaniasis. To evaluate the mechanisms involved in the exaggerated immunologic response in cutaneous and mucosal leishmaniasis.

18 Possible Mechanisms Associated with Exaggerated T Cell Response in Mucosal Leismaniasis Increasing expression of co-stimulatory molecules. Decreased apoptosis. Lack of function of regulatory cytokines or regulatory T cells. Increased frequency of memory/effectors T cells. Increased production of IL-17.

19 Diseases Associated with IL-17 Rheumatoid Arthritis Crohn s Diseasis Ulcerative retocolitis Psoriasis Kidney allograft rejection

20 IL-17 Levels in Supernates of Lymphocyte Cultures Stimulated with Leishmania Antigen or PPD IL-17 (pg/ml) hs 48 hs 96 hs TIME leishmania antigen PPD

21 Frequency of Cells Expressing Co-Stimulatory Molecules in CL and ML Patients 150 Cutaneous (n=8) Mucosal (n=8) Frequency (%) MHCII/CD14 CD80/CD14 CD86/CD14 CD40/CD14 CD40L/CD4 CTLA4/CD4 0

22 Decreased Suppression of SLA-induced IFN-γ in PBMC by Addition of CTLA-4 in CL and ML Patients SLA + CTLA-4 Cutaneous (n=9) Mucosal Controls (n=6) (n=6) SLA + CTLA-4 PPD + CTLA IFN-γ supression (%)

23 Inability of IL-10 in Down-Regulation IFN-γ Production in Mucosal Leishmaniasis Patients 3000 Leish Ag IFN- γ (pg/ml) * 19% * 48% * 86% Leish Ag+IL-10 5ng Leish Ag Leish Ag +IL-10 5ng PPD PPD+ IL-10 5ng 0 ML patients CL patients Healthy controls * % suppression

24 Expression of IL-10 Receptor in ML and CL Lesions % cells expressing IL-10 receptor A B CL ML CL ML * Number of IL-10 receptor+ cells * C Intensity of IL-10 receptor Intensity expression of IL-10 receptor 1 2 CL ML

25 Cell Activation Markers in Mucosal and Cutaneous Leishmaniasis Frequency (%) Cutaneous Mucosal 10 0 CD4+/CD62L- CD4+/CD28- CD+/CD69+

26 Conclusions 1. Immunological response at lesion site in cutaneous and mucosal leishmaniasis is charactherized by over expression of IFN-γ,TNF-α, inos, IL-10 and increased frequency of cells expressing granzyme. 2. Exacerbated type 1 immune response in cutaneous and mucosal leishmaniasis is associated with pathology. 3. There is a decreased ability of T cells from cutaneous and mucosal leishmaniasis patients to be modulated by IL-10 and CTLA-4.

27 Collaborators Lucas P. Carvalho Olívia Bacellar Sara Passos Hélio Lessa Argemiro D Oliveira Júnior Marcus Lessa Luís Henrique Guimarães Amélia Ribeiro de Jesus Albert Schriefer Roque Almeida Maria Elisa Rosa Paulo Machado Walderez Dutra Kenneth Gollob TMRC-NIH AI 30639