Co-expression of chemotactic ligand receptors on human peripheral blood monocytes.
Co-expression of chemotactic ligand receptors on human peripheral blood monocytes.
复制标题
人外周血单核细胞上趋化配体受体的共表达。
作者：
K. Ohura;I. Katona;L. Wahl;D. Chenoweth;S. Wahl
单核细胞的定向迁移依赖于细胞表面受体和特异性趋化配体的相互作用。为了确定是否循环的人单核细胞表达多种趋化配体受体或是否存在单核细胞亚群与一个单一的受体特异性，两个趋化配体，N-甲酰基甲硫氨酰亮氨酰苯丙氨酸（FMLP）和C5 a的非重叠荧光探针，开发同时评估这些配体的受体在单个单核细胞的表达。随后与不同荧光染料标记的C5 a和FMLP探针以及对单核细胞不同亚群上的抗原决定簇具有特异性的单克隆抗体一起孵育，然后用双参数流动显微荧光测定法进行分析，表明表达C5 a和FMLP受体的细胞是OKM 1、Mac-1和Fc γ受体阳性群体。此外，证明了约90%的外周血单核细胞表达FMLP受体，并且大多数FMLP+细胞也是C5 a受体阳性的。此外，C5 a和FMLP的趋化性配体受体密度从低到高的平行光谱得到证实。进一步的分析显示，静息外周血单核细胞上的趋化性配体受体的密度与通过HLA-DR表达测量的单核细胞成熟水平无关。阐明单核细胞趋化性受体-配体相互作用，导致迁移和/或激活可能提供洞察单核细胞功能的调节炎症。
Directed migration of monocytes is dependent upon interaction of cell surface receptors and specific chemotactic ligands. To determine whether circulating human monocytes express multiple chemotactic ligand receptors or whether subpopulations of monocytes exist with a single receptor specificity, nonoverlapping fluorescent probes for two chemotactic ligands, N-formyl methionyl leucyl phenylalanine (FMLP) and C5a, were developed to simultaneously evaluate the expression of receptors for these ligands on individual monocytes. The subsequent incubation with different fluorochrome labeled C5a and FMLP probes and monoclonal antibodies specific for antigenic determinants on distinct subsets of mononuclear cells followed by analysis with dual parameter flow microfluorometry indicated that cells that express C5a and FMLP receptors are the OKM1, Mac-1, and Fc gamma receptor positive population. Furthermore, it was demonstrated that approximately 90% of peripheral blood monocytes expressed FMLP receptors, and the majority of FMLP+ cells were also C5a receptor positive. In addition, a parallel spectrum of chemotactic ligand receptor density from low to high levels was demonstrated for both C5a and FMLP. Additional analysis revealed that the density of chemotactic ligand receptors on resting peripheral blood monocytes did not correlate with monocyte maturation levels measured by HLA-DR expression. Elucidation of the monocyte chemotactic receptor-ligand interactions that lead to migration and/or activation may provide insight into the regulation of monocyte function in inflammation.