Role of antigen-presenting cells in non-ulcerated skin lesions caused by Leishmania (Leishmania) infantum chagasi

Author(s)

Pacheco, Carmen M. Sandoval M. ; Flores, Gabriela V. Araujo V. ; Ferreira, Aurea F. F. ; da Matta, Vania L. R. ; Gomes, Claudia M. de Castro M. ; Sosa-Ochoa, Wilfredo H. H. ; Zuniga, Concepcion ; Silveira, Fernando T. T. ; Corbett, Carlos E. P. ; Laurenti, Marcia D.

• Document type: Journal article
• Source: PARASITE IMMUNOLOGY; v. N/A, p. 11-pg., 2023-01-31.

Abstract

In Central America, infection by Leishmania (Leishmania) infantum chagasi causes visceral leishmaniasis and non-ulcerated cutaneous leishmaniasis (NUCL). This work aimed to evaluate the participation of subpopulations of antigen-presenting cells in skin lesions of patients affected by NUCL through double-staining immunohistochemistry using cellular and intracellular markers. Twenty-three skin biopsies from patients affected by NUCL were used. Histological sections stained by HE were used for histopathological study. Immunohistochemical studies were performed using primary antibodies against Langerhans cells, dermal dendritic cells, T lymphocytes, and the cytokines IL-12, IFN-gamma, TNF-alpha, iNOS, and IL-10. The histopathological lesions were characterized by an inflammatory infiltrate, predominantly lymphohistiocytic, of variable intensity, with a diffuse arrangement associated with epithelioid granulomas and discreet parasitism. Double-staining immunohistochemistry showed higher participation of dendritic cells producing the proinflammatory cytokine IL-12 in relation to the other evaluated cytokines. Activation of the cellular immune response was marked by a higher density of CD8 Tc1-lymphocytes followed by CD4 Th1-lymphocytes producing mainly IFN-gamma. The data obtained in the present study suggest that antigen-presenting cells play an important role in the in situ immune response through the production of proinflammatory cytokines, directing the cellular immune response preferentially to the Th1 and Tc1 types in NUCL caused by L. (L.) infantum chagasi. (AU)

• FAPESP's process: 18/04698-6 - Non-ulcerated or atipycal Cutaneous Leishmaniasis caused by Leishmania (L.) infantum chagasi in the municipality of Amapala, Valle, Honduras: immunohistopathological characterization of skin lesions with emphasis in the participation of antigen presenting cells
• Grantee: Carmen Maria Sandoval Pacheco
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 17/24834-9 - Evaluation of the experimental infection in hamster by isolated parasites of atypical cutaneous lesion and human visceral caused by Leishmania (L.) infantum chagasi in the municipality of Amapala, Valle, Honduras
• Grantee: Gabriela Venicia Araujo Flores
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 14/50315-0 - Leishmaniasis in Latin America: an advanced perspective on immunopathogenetic factors of cutaneous and visceral infection, immunomodulators of the sandflies vector saliva and immunogenic exo-antigens of Leishmania (L.) infantum chagasi as vaccine candidates
• Grantee: Marcia Dalastra Laurenti
• Support Opportunities: Research Projects - Thematic Grants