Wagner C, Hänsch G M, Stegmaier S, Denefleh B, Hug F, Schoels M
Institut für Immunologie der Universität Heidelberg, Heidelberg, Germany.
Eur J Immunol. 2001 Apr;31(4):1173-80. doi: 10.1002/1521-4141(200104)31:4<1173::aid-immu1173>3.0.co;2-9.
The complement receptor 3 (CR3; CD11b/CD18) is present exclusively on leukocytes, particularly on NK cells, monocytes and polymorphonuclear neutrophils. Approximately 10% of peripheral T lymphocytes and, as we found now mainly CD8(+) cells, expressed CD11b. Upon stimulation, however, expression of CD11b was up-regulated also on CD4(+) cells. Stimulation of T cells either by cross-linked anti-CD3 and IL-2 or by mononuclear cells and mitogen yielded up to 28% CD11b(+) T cells. The majority of CD11b(+) T cells also expressed CD56. T cell lines established from healthy donors were also found to express CR3. When restimulated up to 90% of cells became positive for CD11b making those cells an ideal tool for studying the functional role of CD11b. Antibodies to CD11b and bona fide ligands for the complement receptor inhibited the anti-CD3-induced T cell proliferation and as well as IL-2 release. In contrast, proliferation of a CD11b(-) T cell line was not inhibited. Taken together, our data indicate an activation-dependent expression of the complement receptor on T cells and suggest a regulatory function.
补体受体3（CR3；CD11b/CD18）仅存在于白细胞上，尤其是自然杀伤细胞、单核细胞和多形核中性粒细胞。大约10%的外周血T淋巴细胞，正如我们现在发现的主要是CD8(+)细胞，表达CD11b。然而，在受到刺激后，CD4(+)细胞上的CD11b表达也会上调。通过交联抗CD3和白细胞介素-2或通过单核细胞和有丝分裂原刺激T细胞，可产生高达28%的CD11b(+) T细胞。大多数CD11b(+) T细胞也表达CD56。从健康供体建立的T细胞系也被发现表达CR3。当再次刺激时，高达90%的细胞对CD11b呈阳性，使这些细胞成为研究CD11b功能作用的理想工具。抗CD11b抗体和补体受体的真正配体抑制了抗CD3诱导的T细胞增殖以及白细胞介素-2的释放。相比之下，CD11b(-) T细胞系的增殖没有受到抑制。综上所述，我们的数据表明补体受体在T细胞上存在激活依赖性表达，并提示其具有调节功能。
