Eosinophils and immune mechanisms. III. Production of the lymphokine eosinophil stimulation promoter by mouse T lymphocytes.

The lymphoid cell population responsible for production of eosinophil stimulation promoter (ESP), a lymphokine which increases migration of eosinophils, was investigated in murine Schistosoma mansoni infection. Con A challenge induced ESP production, whereas LPS did not. Prior treatment with anti-thetaC3H alloantiserum plus complement in vitro eliminated ESP production; in vivo treatment with rabbit anti-mouse thymocyte serum consistently reduced ESP production by splenic lymphoid cells, but affected lymph node cell ESP production only after exceptionally large doses. Thymocytes did not produce significant amounts of ESP; nor did lymphoid cells from congenitally athymic mice. Depletion of B lymphocytes and macrophages by nylon fiber adherence eliminated antigen-induced ESP production; this was partially restored by addition of non-immune, 72-hr peritoneal exudate cells. Con A-induced ESP production was not affected by nylon fiber treatment. These results demonstrate that ESP is produced by an ATS-sensitive, peripheralized T lymphocyte population, and suggest a macrophage requirement for antigen-induced production of this lymphokine.