Webster E L, Tracey D E, Jutila M A, Wolfe S A, De Souza E B
Laboratory of Neurobiology, National Institute on Drug Abuse, Baltimore, Maryland 21224.
Endocrinology. 1990 Jul;127(1):440-52. doi: 10.1210/endo-127-1-440.
CRF is a primary integrator of the organism's coordinated neuroendocrine, autonomic, behavioral, and immune responses to stress. In the present study the identity of the cell type(s) expressing CRF receptors in mouse spleen was determined using a combination of cell fractionation and receptor-binding techniques. Autoradiographic studies of the distribution of [125I]Tyro-ovine CRF [( 125I]oCRF)-binding sites in spleen localized CRF receptors primarily to the red pulp and marginal zones. The distribution pattern of [125I]oCRF-binding sites closely resembled the pattern of India ink accumulated in phagocytic cells in the same sections. To identify the specific cell type(s) expressing CRF receptors, [125I]oCRF-binding activity was evaluated in splenic cell populations fractionated on the basis of their physical and functional properties. Macrophages were identified in each fraction by their phagocytosis of polystyrene beads and membrane labeling with MONTS-4, a monoclonal antibody specific for resident macrophages. Spleen cells were fractionated by adherence to glass bead or Sephadex G-10 columns, phagocytosis of carbonyl iron particles, and centrifugation on discontinuous Percoll gradients. By all fractionation methods, there was a significant correlation of [125I]oCRF binding with both phagocytic activity (r = 0.75; P less than 0.001) and MONTS-4 staining (r = 0.84; P less than 0.001), strongly suggesting that CRF receptors are primarily expressed on resident splenic macrophages. However, there was essentially no specific binding of [125I]oCRF to either resident or elicited peritoneal macrophages or to several monocyte/macrophage, B-cell, or T-cell lines. While these results suggest that the expression of CRF receptors may be restricted to a population of splenic macrophages, they do not exclude the possibility that CRF receptors may be induced on resident macrophages in spleen and other immune system-related tissues by factors present in the microenvironment.
促肾上腺皮质激素释放因子（CRF）是机体对压力产生协调的神经内分泌、自主神经、行为和免疫反应的主要整合因子。在本研究中，采用细胞分级分离和受体结合技术相结合的方法，确定了小鼠脾脏中表达CRF受体的细胞类型。对脾脏中[125I]酪氨酸 - 羊CRF（[125I]oCRF）结合位点分布的放射自显影研究表明，CRF受体主要定位于红髓和边缘区。[125I]oCRF结合位点的分布模式与同一切片中吞噬细胞中积累的印度墨水的模式非常相似。为了鉴定表达CRF受体的特定细胞类型，在根据其物理和功能特性分级分离的脾细胞群体中评估了[125I]oCRF结合活性。通过吞噬聚苯乙烯珠以及用MONTS - 4（一种针对驻留巨噬细胞的单克隆抗体）进行膜标记，在每个分级分离物中鉴定出巨噬细胞。脾细胞通过附着于玻璃珠或葡聚糖凝胶G - 10柱、吞噬羰基铁颗粒以及在不连续的 Percoll 梯度上离心进行分级分离。通过所有分级分离方法，[125I]oCRF结合与吞噬活性（r = 0.75；P小于0.001）和MONTS - 4染色（r = 0.84；P小于0.001）均存在显著相关性，强烈表明CRF受体主要在驻留脾巨噬细胞上表达。然而，[125I]oCRF与驻留或诱导的腹膜巨噬细胞或几种单核细胞/巨噬细胞、B细胞或T细胞系基本上没有特异性结合。虽然这些结果表明CRF受体的表达可能仅限于脾巨噬细胞群体，但它们并不排除CRF受体可能被微环境中存在的因素诱导在脾脏和其他免疫系统相关组织中的驻留巨噬细胞上表达的可能性。
