Effect of methylprednisolone on the production of neutrophil migration inhibition factor by T lymphocytes (NIF-T)

Glucocorticoids may suppress cell-mediated immunity by inhibiting lymphocyte mediator production or reducing the responsivenes of target cells to these mediators. Our laboratory recently described a newly recognized T-lymphocyte mediator, neutrophil migration inhibition factor from T-lymphocytes (NIF-T). In this report we assessed the effect of glucocorticoids on NIF-T activity. Methylprednisolone (MP) at concentrations as low as 10^-7M inhibited NIF-T activity from peripheral blood lymphocytes (PBL) in response to staphylococcal protein A (SPA) and concanavalin A (Con A). However, MP at concentrations as high as 10^-4 M did not alter the responsiveness of neutrophils to NIF-T. Therefore, the effect of MP on NIF-T activity was due to inhibition of mediator production. The effect of MP on NIF-T production was reversible in 24 hours. This finding is consistent with the clinical observation that alternate day therapy does not suppress cell-mediated immunity. Serum taken from a patient as early as one hour after oral administration of 100 mg of prednisone inhibited NIF-T production in vitro; serum obtained at 48 hr after prednisone had no measurable effect on NIF-T activity. In addition, MP inhibited NIF-T production by previously activated lymphocytes.