A simple method for the production of migration inhibitory factor by concanavalin A - stimulated lymphocytes.

A simple method for preparing culture supernatants containing macrophage migration inhibitory factor (MIF) by pulse exposure to guinea pig lymphocytes to concanavalin A (ConA), is described. The method is based on the property of originally nonadherent lymphocytes to attach to the flask surface in the presence of Con A. The Con A-induced lymphocyte 'monolayer' can be easily rinsed, allowing the removal of free Con A without repeated, cell damaging centrifugation. The Con A-pulsed lymphocytes are cultured for 24 h in medium and supernatants containing MIF but free of undesired Con A are regularly obtained.