IFN-gamma- and IL-5-producing cells compartmentalize to different lymphoid organs in Trichinella spiralis-infected mice.

The differential induction of cytokines associated with Th1 and Th2 subsets has recently been described during Trichinella spiralis infection. Increased levels of resistance appear to correlate with elevated levels of the Th1-associated cytokines, IFN-gamma and IL-2. In the present report, a filter immunoplaque assay is used to quantify the actual numbers of cells that secrete IFN-gamma and IL-5. It is demonstrated that, in T. spiralis-infected B10.Q mice, Th1- and Th2-associated responses are compartmentalized to different lymphoid organs. Thus, Ag-induced IFN-gamma-producing cells predominate in the spleen, whereas IL-5-producing cells prevail in the mesenteric lymph nodes (MLN). A corresponding compartmentalization of Ag-specific IgA and IgG1 antibody-secreting cells to the MLN is also noted. The virtual absence of Th1-associated responses in the MLN appears to be an Ag-associated phenomenon. MLN from either naive or T. spiralis-infected mice do have the capacity to secrete IFN-gamma if stimulated with Con A. The striking compartmentalization of Ag-driven cytokine responses seen in this parasite system may facilitate study of the mechanisms that regulate the induction of Th1 and Th2 subsets.