T cell receptor V beta repertoire in the thymus and spleen of mice infected with Trypanosoma cruzi.
The T cell receptor (TCR) V beta repertoire was studied in BALB/c, CBA/HJ, and CBA/J mice experimentally infected with Trypanosoma cruzi. The percentage of expression of 14 V beta chains of the variable domain of the TCR in the thymus and spleen was evaluated. In the thymus of acutely infected with BALB/c and CBA/HJ mice there was an increase in the expression of positively selected V beta families. These changes in the V beta chains usage in the thymus paralleled the enrichment of CD4+ and CD8+ single-positive T cells. During the acute infection, several changes were observed in the peripheral expression of V beta families, such as of V beta 6 in BALB/c (a 36% increase in CD8+ T cells of the corresponding levels of V beta), of V beta 8 in CBA/HJ (a 37% decrease in CD8+ cells), and of V beta chains 8 and 14 in CBA/J mice (V beta 14+CD4+ cells increased 19%, and V beta 8 expression decreased 19 and 33% in CD4+ and CD8+ cells, respectively). In chronically infected BALB/c and CBA/HJ mice, no change in the V beta families was observed, neither in the thymus nor in the spleen. In acutely infected mice, the alterations of the peripheral expression of positively selected V beta families could be due to the stimulation by T. cruzi antigens and/or cytokines; the homeostatic mechanism/s that maintains the selection of the TCR V beta repertoire did not seem to be severely affected during the infections.
Cardoni
R L
RL
Instituto Nacional De Chagas Dr. M. Fatala Chabén, Buenos Aires, Argentina.
Antunez
M I
MI
Orn
A
A
Grönvik
K O
KO
D000818:Animals; D014355:Chagas Disease / Q000276:immunology* / Q000378:metabolism*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008808:Mice, Inbred CBA; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000032:analysis*; D013045:Species Specificity; D013154:Spleen / Q000276:immunology* / Q000378:metabolism / Q000469:parasitology; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D013950:Thymus Gland / Q000276:immunology* / Q000378:metabolism / Q000469:parasitology
D016693:Receptors, Antigen, T-Cell, alpha-beta