Characterization of T helper cell responses to the trypanosome variant surface glycoprotein.

摘要: T cell responses to the variant surface glycoprotein (VSG) previously have not been detected in animals infected with African trypanosomes despite fact that such make strong T-dependent B VSG molecules displayed by parasites. In present study, we examined 10.BR mice for VSG-specific Th at different times after infection Trypanosoma brucei rhodesiense clone LouTat 1. populations derived from tissues were tested their ability proliferate and secrete cytokines when stimulated purified 1 VSG. Furthermore, lines clones immunized phenotypic functional profiles comparison of mice. The results this study show cells consistently peripheral lymphoid as spleen or lymph nodes animals. contrast, Ag-specific detectable principally peritoneal Peritoneal did response VSG, yet produced substantial cytokine stimulated; IFN-gamma IL-2, without IL-4. cellular phenotype VSG-responsive was classical all CD4-positive expressed CD3 alpha/beta TCR membrane complex. Thus, appears preferentially stimulate a Th1 subset during infection. Intrinsic molecular characteristics molecule induce response, however, since VSG-immunized characteristic both Th2 cells. Isolation selected demonstrated these same membrane-phenotypic type-specific, APC-dependent, I-Ak-restricted responses. summary, experiments provide first direct evidence level. appear be anatomically compartmentalized exhibit clonal maturation (cytokine production) but expansion (proliferation) antigenic stimulation. predict predisposes mount including generated, an experimental basis examining regulation immune