Impaired Lymphocyte Profile in Schistosomiasis Patients with Periportal Fibrosis. (18th November 2013) - Cardoso, Luciana Santos
Abstract : The Th2 immune response in chronic schistosomiasis is associated with the development of periportal fibrosis. However, little is known about the phenotype and activation status of T cells in the process. Objective . To evaluate the profile of T cells in schistosomiasis patients with periportal fibrosis. Methods . It was a cross-sectional study, conducted in the village of Agua Preta, Bahia, Brazil, which included 37 subjects with periportal fibrosis determined by ultrasound. Peripheral blood mononuclear cells were obtained by the Ficcol-hypaque gradient and the frequency of T cells expressing the surface markers CD28, CD69, CD25, and CTLA-4 was determined by flow cytometry. Results . The frequency of CD4 + CD28 + T lymphocytes was higher in individuals with moderate to severe fibrosis compared to patients with incipient fibrosis. We did not observe any significant difference in the frequency of CD4 + T cells expressing CD69 among groups of individuals. There was also no significant difference in the frequency of CD8 + T cells expressing CD28 or CD69 among the studied groups. Individuals with moderate to severe fibrosis presented a lower frequency of CD8 + T cells, CD4 + CD25 high T cells, and CD4 + CTLA-4 + T cells when compared to patients without fibrosis or incipient fibrosis. The frequency of CD4 + CD25 low cells did not differ between groups. Conclusion . The high frequency of activated T cells coinciding with a low frequency of putative Treg cells may account for the development of periportal fibrosis in human schistosomiasis.