Production of migration inhibitory factor by Listeria-immune mouse T lymphocytes, but not B lymphocytes

Antigens and B cell mitogens have been reported to induce migration inhibition factor (MIF) production by mouse B cells. Immune resistance to the intracellular bacterium, Listeria monocytogenes is thought to involve T cells, but not B cells. Since Listeria-derived components are B cell, but not T cell mitogens, it was important to determine whether these materials could stimulate secretion of the lymphokine, MIF by T cells, B cells, or both. Thus populations of whole, unfractionated spleen cells, obtained from normal and Listeria-immune BDF1 mice, were cultured with or without 100 micrograms/ml of Listeria intracellular product (LIP). The culture supernatants obtained 24 h later were assayed for MIF activity using the in vitro macrophage migration inhibition assay. Data obtained show that immune T lymphocytes release MIF in response to specific Listeria antigens, but that spleen B cells from immune and normal mice, obtained as immune, nylon-wool-adherent cells treated with anti-T-cell serum plus complement, are not capable of releasing MIF. This suggests that release of lymphokines by Listeria-immune or normal B cells stimulated with Listeria-derived antigens and mitogens is unlikely to contribute to resistance against Listeria in vivo.