Composition of T cell immune response in cutaneous leishmaniasis

Background There is wide range of clinical presentations of cutaneous leishmaniasis, which are dependent on different species of the parasite as well as immune response offered by the host. World research is now focused on the host’s immune response in this disease. Th 1 type T cell response seems to have a critical role in final outcome of this parasitic infection. Objective This study was done to analyze quantitatively the cellular immune host response by demonstrating various T cell subsets in the lesions of acute Old World cutaneous leishmaniasis. Patients and methods The study was jointly conducted in Military Hospital, Rawalpindi and Armed Forces Institute of Pathology, Rawalpindi, Pakistan. 40 biopsies of proven active skin lesions of cutaneous leishmaniasis were evaluated after processing for various immunophenotype cells by using monoclonal antibodies. 15 normal skin biopsies were also studied for comparison and control. Total T cell counts and differential T cell counts were recorded in 10 microscopic fields, using light microscope (x 250) in each tissue specimen. Means and percentages were calculated. Data were analysed by applying ANOVA test using INSTAT programme. Results Predominant T cell infiltrate was observed in all skin lesions. Total T cell, CD3+ cells, and NK cells counts were seen extremely higher when compared with normal skin biopsies (p 0.001). The difference in CD4+, CD8+, CD19+ cells counts was not significant (p 0.05). Conclusion Skin infiltrate is T cell rich and CD3+ and NK cells forms the major portion of the T cell population in cases of acute leishmaniasis.