Different T helper cell subsets elicited in mice utilizing two different adjuvant vehicles: the role of endogenous interleukin 1 in proliferative responses.

Mice were immunized with either poly(Glu, Arg, Ala) or poly(Glu, Lys, Phe) contained in two different adjuvant preparations, alum (A1K(SO4)2) or complete Freund's adjuvant (CFA), and in vitro antigen-driven proliferative responses of lymph node cells were assayed 4-16 days later. After immunization with antigens on alum, endogenous interleukin 1 (IL-1) as well as interleukin 4 (IL-4) production was required for the proliferation of the elicited T cells as inclusion of either polyclonal goat anti-mouse IL-1 alpha or monoclonal anti-mouse IL-4 (11B11) in the cultures inhibited proliferative responses to antigen. In contrast, proliferative responses of cells elicited by antigen in CFA were not inhibited by either anti-IL-1 or anti-IL-4. Monoclonal antimouse CD4 (GK 1.5) inhibited proliferative responses regardless of which adjuvant was used to elicit antigen-reactive cells. These data indicated that phenotypically different subpopulations of CD4+ cells were elicited by the same antigen administered in different adjuvant preparations, Th2-like cells after immunization with polymers on alum and Th1-like cells after immunization with antigens in CFA. An examination of the isotypes of polymer-specific antibodies present in the sera of immunized mice also supported this conclusion.