Sarcoid lymphocytes: spontaneous transformation and release of macrophage migration inhibition activity.

A group of 26 untreated patients with histologically confirmed sarcoidosis were studied. Multiple immunologic parameters were defined, including spontaneous morphologic lymphoblastic transformation, spontaneous production of macrophage inhibitory factor activity, 8-day cell culture lymphocyte count, phytohemagglutinin-induced lymphoblastic transformation, and cutaneous reactivity to a battery of recall antigens. The in vitro impairment of phytohemagglutinin-induced lymphoblastic transformation occurred only in patients with more disseminated disease (Group II). Cutaneous anergy did not correlate either with the degree of in vitro phytohemagglutinin-induced lymphoblastic transformation or with the extent and known duration of disease. The in vitro occurrence of enhanced spontaneous morphologic lymphoblastic transformation and spontaneous release of macrophage inhibitory factor activity were demonstrated, but these did not always occur in the same lymphocyte cultures and appeared to be independent parameters of immunologic activity. In conclusion, it is suggested that, contrary to the previously held view of general depression of delayed hypersensitivity in sarcoidosis, the immune apparatus of patients with sarcoidosis may be hyperreactive. Further, it proposed that determination of the macrophage migration index may prove valuable in evaluating the activity of the disease.