Warren M K, Vogel S N
J Immunol. 1985 Apr;134(4):2462-9.
Two macrophage markers associated with differentiation are the Fc receptor (FcR) and the Ia antigen. Expression of these markers is increased with IFN-gamma treatment, although some evidence suggests that the induction pathway for Fc receptor and Ia antigen expression may be dissociable. In this study, the effect of glucocorticoids on basal and IFN-induced levels of Fc-mediated phagocytosis and Ia antigen expression was investigated. Macrophages incubated for 2 days with glucocorticoids alone showed no change in basal levels of Fc-mediated phagocytosis. However, incubation with glucocorticoids plus IFN-gamma resulted in increased Fc-mediated phagocytosis and binding to a much greater extent than IFN-gamma treatment alone. This enhancement was specific for IFN-gamma, because the IFN-beta-induced increase in Fc-mediated phagocytosis and binding was not affected by glucocorticoids. In contrast to the expression of Fc receptor capacity, both basal and IFN-gamma-induced levels of Ia antigen expression were inhibited by glucocorticoids. The glucocorticoid effect on these two markers was not observed with other steroid hormones, nor was it altered by inhibitors of the arachidonic acid pathway. The findings of this study provide additional evidence that induction of Fc receptor and Ia antigen by IFN-gamma occurs by different mechanisms.
两种与分化相关的巨噬细胞标志物是Fc受体（FcR）和Ia抗原。这些标志物的表达在γ干扰素处理后会增加，尽管一些证据表明Fc受体和Ia抗原表达的诱导途径可能是可分离的。在本研究中，研究了糖皮质激素对基础水平以及干扰素诱导的Fc介导的吞噬作用和Ia抗原表达水平的影响。单独用糖皮质激素孵育2天的巨噬细胞，其Fc介导的吞噬作用基础水平没有变化。然而，用糖皮质激素加γ干扰素孵育导致Fc介导的吞噬作用和结合增加，其程度比单独用γ干扰素处理大得多。这种增强对γ干扰素具有特异性，因为β干扰素诱导的Fc介导的吞噬作用和结合增加不受糖皮质激素影响。与Fc受体能力的表达相反，基础水平以及γ干扰素诱导的Ia抗原表达水平均受到糖皮质激素的抑制。其他甾体激素未观察到糖皮质激素对这两种标志物的作用，花生四烯酸途径的抑制剂也未改变这种作用。本研究结果提供了额外的证据，表明γ干扰素诱导Fc受体和Ia抗原是通过不同机制发生的。
