Dijkstra I M, de Haas A H, Brouwer N, Boddeke H W G M, Biber K
Department of Medical Physiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
Glia. 2006 Dec;54(8):861-72. doi: 10.1002/glia.20426.
Since activated microglia are able to phagocytose damaged cells and subsequently express major histocompatibility complex class II (MHC-II) and co-stimulatory proteins, they are considered to function as antigen presenting cells (APCs) in the central nervous system. The maturation and migratory potential of professional APCs is associated with the expression of chemokine receptor CCR7. We therefore investigated whether the immunological activation of microglia induces CCR7 expression. We here present that activation of cultured microglia by both the innate antigen lipopolysaccharide and protein antigen ovalbumin rapidly induces CCR7 expression, accompanied by increased MHC-II expression. Moreover, it is shown that CCR7 expression in IBA-1 positive cells is induced during the symptom onset and progression of experimental autoimmune encephalomyelitis, a rodent model for multiple sclerosis. These results suggest that microglia express CCR7 under specific inflammatory conditions, corroborating the idea that microglia develop into APCs with migratory potential toward lymphoid chemokines.
由于活化的小胶质细胞能够吞噬受损细胞，并随后表达主要组织相容性复合体II类（MHC-II）和共刺激蛋白，因此它们被认为在中枢神经系统中作为抗原呈递细胞（APC）发挥作用。专业APC的成熟和迁移潜力与趋化因子受体CCR7的表达有关。因此，我们研究了小胶质细胞的免疫激活是否会诱导CCR7表达。我们在此表明，天然抗原脂多糖和蛋白抗原卵清蛋白对培养的小胶质细胞的激活会迅速诱导CCR7表达，并伴随着MHC-II表达的增加。此外，研究表明，在实验性自身免疫性脑脊髓炎（一种多发性硬化症的啮齿动物模型）的症状发作和进展过程中，IBA-1阳性细胞中的CCR7表达会被诱导。这些结果表明，小胶质细胞在特定炎症条件下表达CCR7，证实了小胶质细胞发展成为对淋巴趋化因子具有迁移潜力的APC这一观点。
