Heterogeneity of eosinophil chemotactic factors produced by splenic T cells of Schistosoma japonicum-infected mice

Spleen cells of Schistosoma japonicum-infected mice produced eosinophil chemotactic factors (ECF-Ls) upon stimulation with soluble egg antigen preparation (SEA) and Con A, while spleen cells from uninfected mice produced ECF-L upon stimulation with Con A but not with SEA. Depletion of CD4⁺ T cells, but not of CD8⁺ T cells, almost completely removed Con A-induced ECF-L production. In contrast, depletion of CD8⁺ T cells completely abolished SEA-induced ECF-L production while depletion of CD4⁺ T cells did not, indicating that CD4⁺ CD8⁻ T cells and CD4⁻CD8⁺ T cells play essential roles for the production of Con A-induced ECF-L and SEA-induced ECF-L, respectively. Con-A-induced ECF-L had a high affinity to Con A-Sepharose but not to Procion Red agarose. In contrast, SEA-induced ECF-L bound to Procion Red agarose, but not to Con A-Sepharose. A gel permission HPLC analysis revealed that the apparent molecular weight of Con A-induced ECF-L and SEA-induced ECF-L was 16 kDa and 35 kDa, respectively. Both Con A-induced ECF-L and SEA-induced ECF-L had a similar isoelectric point (pI 3.5–3.6). These results indicate that selective stimulation of either CD4⁺ or CD8⁺ T cells of S. japonicum-infected mice produces heterogeneous ECF-L.