Letters to the Editor

Abstract

Abstract August 28, 1973 Sir: In many manuscripts published recently in the Journal of Immunology and in other journals as well, the authors have used the leukocyte migration inhibition test, and have indicated in the results or discussion that they were measuring production of migration inhibitory factor (MIF). I think that this practice is inaccurate and confusing for the following reasons: The leukocyte migration inhibition test involves evaluation of migration of peripheral buffy coat leukocytes from capillary tubes or from wells in agarose plates. Although both tests have been shown to correlate with skin test reactivity, the leukocyte migration inhibition test differs from the macrophage migration inhibition test in that the migrating cell population probably represents polymorphonuclear leukocytes rather than macrophages. While it does appear that both tests are mediated by cell free mediators, to my knowledge, there have been no reports on the characterization of the mediator responsible for inhibition of leukocyte migration, and it is not known whether or not this mediator is the same as that responsible for inhibition of macrophage migration.