Rinder H M, Bonan J L, Rinder C S, Ault K A, Smith B R
Department of Laboratory Medicine, Yale University School of Medicine, New Haven, CT 06510.
Blood. 1991 Oct 1;78(7):1760-9.
To examine the possible receptor-ligand pairs mediating adhesion of activated and "unactivated" platelets to leukocytes and the kinetics of leukocyte-platelet binding, we developed a flow cytometric assay using isolated cell fractions to accurately measure heterotypic cell adhesion, including both total leukocyte-platelet conjugate formation as well as the number of platelets bound per leukocyte. We have shown that (1) activated platelet binding to both polymorphonuclear leukocytes (PMN) and monocytes is dependent on both a specific epitope (blocked by monoclonal antibody G1) of granule membrane protein-140 (GMP-140) and the presence of divalent cations; (2) unactivated platelets bind to 87% of viable, resting monocytes but to only 34% of PMN; (3) the receptor(s) on unactivated platelets that mediate adhesion to PMN and monocytes do not require divalent cations and become nonfunctional after thrombin activation; and (4) the kinetics of platelet adhesion to monocytes and PMN indicate that monocyte adhesion is favored over neutrophil adhesion. We conclude that platelet-heterotypic cell adhesion is a dynamic process reflecting the activation status of the platelet and differential binding abilities of leukocytes.
为了研究介导活化和“未活化”血小板与白细胞黏附的可能的受体 - 配体对以及白细胞 - 血小板结合的动力学，我们开发了一种流式细胞术检测方法，使用分离的细胞组分来准确测量异型细胞黏附，包括白细胞 - 血小板共轭体的总形成以及每个白细胞结合的血小板数量。我们已经表明：（1）活化血小板与多形核白细胞（PMN）和单核细胞的结合既依赖于颗粒膜蛋白 - 140（GMP - 140）的一个特定表位（被单克隆抗体G1阻断），也依赖于二价阳离子的存在；（2）未活化血小板与87%的存活静止单核细胞结合，但仅与34%的PMN结合；（3）未活化血小板上介导与PMN和单核细胞黏附的受体不需要二价阳离子，并且在凝血酶激活后失去功能；（4）血小板与单核细胞和PMN黏附的动力学表明，单核细胞黏附优于中性粒细胞黏附。我们得出结论，血小板 - 异型细胞黏附是一个动态过程，反映了血小板的活化状态和白细胞的差异结合能力。
