2-mercaptoethanol in vitro and macrophage migration in normal and sensitized guinea pigs.

While the influence of 2-mercaptoethanol (2-ME) on the functions of lymphocytes has rather extensively been investigated, there are almost no data on the action of this thiol compound on macrophages. We examined the effect of 2-ME in vitro (10(-6)-10(-4) M) on migration from capillary tubes of oil elicited peritoneal macrophages of non-immune and immune guinea pigs, sensitized with ovalbumin in complete Freund's adjuvant. This thiol did not affect the random migration of macrophages both in normal and in sensitized animals. Contrary to this, it significantly enhanced the frequency of occurrence and the magnitude of migration inhibition caused by the action of the migration inhibitory factor (MIF) in the examination of delayed hypersensibility by a direct MIF assay. The possible mechanism and the site of action of 2-ME are discussed.