Russell D H, Kibler R, Matrisian L, Larson D F, Poulos B, Magun B E
J Immunol. 1985 May;134(5):3027-31.
Prolactin (PRL) receptors have been identified recently on human peripheral blood mononuclear cells (MNC) and may be involved in the regulation of cell-mediated immunity. Cyclosporine (CsA), an immunosuppressive cyclic endecapeptide utilized to prolong graft survival in human organ transplant patients, affects PRL binding to MNC. At concentrations of CsA from 10(-10) through 10(-8) M, the amount of PRL bound to MNC markedly increased to ca. 400% of controls, whereas CsA concentrations of 10(-6) and 10(-5) M totally inhibited PRL binding to lymphocytes. The ability of low concentrations of CsA to enhance PRL binding was temperature-dependent and did not occur when binding assays were conducted at 4 degrees C. PRL displaced [3H]CsA from lymphocytes with ca. 50% displacement at 10(-9) M PRL and total displacement at concentrations of 10(-7), 10(-6), and 10(-5) M. Growth hormone did not displace [3H]CsA in similar experiments. CsA also did not alter the binding of a beta-receptor antagonist to MNC, again suggesting that CsA was specific in its antagonism of PRL binding. A CsA analog with no immunosuppressive action, cyclosporin H, did not alter PRL binding to MNC. Furthermore, PRL receptors were demonstrated on four cell lines of human and mouse origin. Finally, PRL receptors were identified on purified populations of T and B lymphocytes isolated from human spleens, and CsA again inhibited PRL binding at concentrations of 10(-7) and 10(-6) M. The presence of PRL receptors on T and B lymphocytes suggests that PRL may be involved in the regulation of humoral and cell-mediated immunity, and that one effect of CsA on immune function may be its ability to inhibit the effects of PRL action on these lymphocytes.
最近在人外周血单个核细胞（MNC）上发现了催乳素（PRL）受体，其可能参与细胞介导免疫的调节。环孢素（CsA）是一种用于延长人体器官移植患者移植物存活时间的免疫抑制性环十一肽，它会影响PRL与MNC的结合。在10^(-10)至10^(-8)M的CsA浓度范围内，与MNC结合的PRL量显著增加至对照的约400%，而10^(-6)和10^(-5)M的CsA浓度则完全抑制PRL与淋巴细胞的结合。低浓度CsA增强PRL结合的能力依赖于温度，在4℃进行结合试验时不会出现这种情况。PRL以约50%的置换率在10^(-9)M PRL时从淋巴细胞中置换出[3H]CsA，在10^(-7)、10^(-6)和10^(-5)M浓度时完全置换。在类似实验中，生长激素不会置换[3H]CsA。CsA也不会改变β受体拮抗剂与MNC的结合，这再次表明CsA在拮抗PRL结合方面具有特异性。一种无免疫抑制作用的CsA类似物环孢素H不会改变PRL与MNC的结合。此外，在人和小鼠来源的四种细胞系上证实了PRL受体的存在。最后，在从人脾脏分离的纯化T淋巴细胞和B淋巴细胞群体上鉴定出了PRL受体，CsA在10^(-7)和10^(-6)M浓度时再次抑制PRL结合。T淋巴细胞和B淋巴细胞上PRL受体的存在表明PRL可能参与体液免疫和细胞介导免疫的调节，并且CsA对免疫功能的一种作用可能是其抑制PRL对这些淋巴细胞作用的能力。
