Functional studies of Fc receptor-bearing human lymphocytes: effect of treatment with proteolytic enzymes.
Functional studies of Fc receptor-bearing human lymphocytes: effect of treatment with proteolytic enzymes.
复制标题
携带 Fc 受体的人淋巴细胞的功能研究：蛋白水解酶治疗的效果。
作者：
B. Perussia;G. Trinchieri;J. Cerottini
为了分析Fc受体（FcR）在自发细胞介导的细胞毒性（SLMC）中的作用，平行检测了来自单个供体的淋巴细胞与IgG抗体包被的红细胞（EA）形成红细胞的能力，以及介导抗体依赖性细胞毒性（ADCC）和SLMC的能力。选择改变细胞表面FcR表达的实验条件（即，酶处理或与免疫复合物反应后）。胰蛋白酶处理的淋巴细胞仍然表达FcR，并能够介导ADCC，但SLMC完全消除。链霉蛋白酶处理，相反，破坏FcR和ADCC和SLMC。当酶处理的细胞培养长达48小时的FcR在细胞表面重新表达，和两个裂解活性恢复。尽管培养基中和整个试验期间存在F（ab′）2抗人F（ab ′）2抗体，但在培养物中回收了来自去除B细胞的胰蛋白酶处理细胞的SLMC。此外，胰蛋白酶处理的细胞在含有自体血清的培养基中孵育不能重建SLMC。当淋巴细胞与免疫复合物反应时，观察到ADCC和SLMC的调制。在这种情况下，即使在37°C孵育后，裂解活性也不能恢复。当细胞与免疫复合物反应时，在没有Ca++离子的情况下，观察到FcR的调制的部分抑制。两种不同的机制可能存在于ADCC和SLMC进行了讨论。
In order to analyze the role that Fc receptors (FcR) play in spontaneous cell-mediated cytotoxicity (SLMC), lymphocytes from single donors were tested in parallel for their ability to form rosettes with IgG antibody-coated erythrocytes (EA), and to mediate antibody-dependent cytotoxicity (ADCC) and SLMC. Experimental conditions were chosen in which the expression of FcR at the cell surface is altered (i.e., after enzymatic treatment or reaction with immune complexes). Trypsintreated lymphocytes still expressed FcR and were able to mediate ADCC, but SLMC was completely abolished. Pronase treatment, on the contrary, destroyed FcR and both ADCC and SLMC. When the enzyme-treated cells were cultured for up to 48 hr FcR was reexpressed at the cell surface, and both lytic activities were regained. SLMC from B cell-deprived trypsin-treated cells was recovered in culture in spite of the presence of F(ab′)2 anti-human F(ab′)2 antibodies in the culture medium and throughout the test. Moreover, incubation of the trypsintreated cells in medium containing autologous serum could not reconstitute SLMC. When lymphocytes were reacted with immune complexes, a modulation of both ADCC and SLMC was observed. In this case, the lytic activities could not be recovered even after incubation at 37°C. A partial inhibition of the modulation of FcR was observed when the cells were reacted with immune complexes in the absence of Ca++ ion. The possible existence of two different mechanisms operating in ADCC and SLMC is discussed.