CD8+ phenotypical analysis in in chronic chagasic patients with different degree of cardiac disfunction

ALBAREDA MC, LAUCELLA S, TORRES S, VIOTTI M, ARMENTI A, LOCOCO TARLETON R, POSTAN M

Caxambu, Brasil

Congreso; XXVIII Annual Meeting on Basic Research in Chagas Disease. XVII Annual Meeting of Brazilian Society of Protozoology; 2001

The aim of this study was to characterize the CD8+ T lymphocyte repertoire of chronic chagasic patients based on the phenotypic expression of surface markers CD62L, CD45RA, CD45RAO, HLA-DR, CD11a. PBMC cells isolated from 12 patents G0-1 of the Kuschnir classification, mean age 51.5±10.37 and 10 patients with severe cardiac dysfunction (G2-3), mean age of 63,25±7.23, stained and analized by flow cytometry. All data were compared to values from 9 aged-matched non-infected individuals. The expression of CD62L in the CD8+ population was significantly increased in patients from G2-3 (mean percentage of CD8+CD62L+: 12,09±8,19). In contrast the frequency of CD8+CD62L+ cells remained within the range of non-infected individuals in G0-1 patients (mean percentage of CD8+CD62L+ : 3,8±4,78 and 2.71±2.89, respectively). No substantive differences in the expression of the other markers studied were found between the different clinical groups of chronic chagasic patients and non-infected controls. The differential expression of CD62L, a marker present in naive cells, in the CD8+ T lymphocyte pool may suggest abnormalities in the immune response of T. cruzi-infected patients. The significance of this finding remains to be determined. Further characterization of the immunological status of individuals in different chronic stage of infection with T. cruzi may be critical for understanding the dynamics of human Chagas disease.