Modulation of lymphocyte migration by human lymphokines. III. Characterization of a lymphocyte migration inhibitory factor (LyMIF35K).

The lymphokine that augments the migration of nonsensitized T lymphocytes (LCF) has been observed to be predominantly a chemokinetic factor, suggesting that separate lymphocyte migration inhibitory lymphokine(s) might exist. Utilizing a modified Boyden chamber assay, lymphocyte migration inhibitory activity was identified in the culture supernatants of human nylon wool-nonadherent blood mononuclear cells stimulated with concanavalin A in vitro for 48 hr. Sephadex G-100 gel filtration chromatography of these culture supernatants was shown to contain two regions of noncytotoxic migration inhibitory activity for nonsensitized human blood lymphocytes and rat splenic lymphocytes. The 30-40,000 dalton inhibitory activity was further characterized and noted to be cationic by ion-exchange chromatography and isoelectric focusing (pI = 8.6). Its biologic activity was sensitive to neuraminidase and to heat treatment but not to trypsin. The migration inhibitory activity of this factor (LyMIF35K) was directly proportional to its ability to increase lymphocyte adherence.