Partial purification and physicochemical properties of human T cell migration inhibitory factor (TIF)

Supernatants from 24 hr cultures of PHA-pulsed human T lymphocytes inhibit the migration of human peripheral blood T lymphocytes and guinea pig macrophages in vitro. The factor responsible for the inhibition of T lymphocytes provisionally called TIF (T cell migration inhibitory factor) was separated from MIF by preparative PAGE, had apparent molecular weight (m.w.) of 1,000-10,000 daltons and isoelectric point of 3.1. TIF activity was resistant to treatment with trypsin, chymotrypsin and neuraminidase but sensitive to PMSF (phenyl-methyl-sulfonyl-fluoride). This suggests that TIF is presumably different from human MIF and may represent a novel lymphokine which preferentially affects T cell migration in vitro.