Provis J M, Diaz C M, Penfold P L
Department of Clinical Ophthalmology, University of Sydney, N.S.W., Australia.
Perspect Dev Neurobiol. 1996;3(3):213-22.
Microglia of the adult human retina are a heterogeneous population of cells, some having characteristics of dendritic antigen presenting cells (DC) and others resembling macrophages, or MPS cells. Studies of the development of microglial distributions in human retina suggest that cells bearing macrophage markers are ontogenetically distinct from microglia that do not. Quantitative studies indicate that macrophage antigen immunoreactive microglia are a subpopulation CD45- and MHC-immunoreactive microglia. While CD45 and MHC-I and -II immunoreactive microglia are seen in the retina prior to the arrival of the vasculature, significant numbers of macrophage-positive microglia only arrive along with the vascular precursors, at about 14 to 15 weeks of gestation. Microglia appear to enter the retina from the ciliary margin prior to vascularization but from both the optic disc and ciliary margin, postvascularization. Macrophage antigen positive microglia enter the retina mainly via the optic nerve head. It is argued that macrophage-antigen positive microglia become established in the retina as vessel associated (perivascular and paravascular) microglia and that the MHC-positive, but macrophage-antigen negative microglia (representing DC), become established as the parenchymal, ramified microglia of adult retina.
成人人类视网膜的小胶质细胞是一群异质性细胞，一些具有树突状抗原呈递细胞（DC）的特征，另一些则类似于巨噬细胞或髓样细胞（MPS细胞）。对人类视网膜中小胶质细胞分布发育的研究表明，带有巨噬细胞标志物的细胞在个体发生上与不带有该标志物的小胶质细胞不同。定量研究表明，巨噬细胞抗原免疫反应性小胶质细胞是CD45和MHC免疫反应性小胶质细胞的一个亚群。虽然在血管系统到达之前视网膜中就可见到CD45以及MHC - I和 - II免疫反应性小胶质细胞，但大量巨噬细胞阳性小胶质细胞直到妊娠约14至15周时才随着血管前体细胞一同到达。在血管形成之前，小胶质细胞似乎从睫状缘进入视网膜，但在血管形成之后，则从视盘和睫状缘进入。巨噬细胞抗原阳性小胶质细胞主要通过视神经乳头进入视网膜。有人认为，巨噬细胞抗原阳性小胶质细胞在视网膜中作为与血管相关（血管周围和血管旁）的小胶质细胞而确立，而MHC阳性但巨噬细胞抗原阴性的小胶质细胞（代表DC）则作为成人视网膜的实质、分支状小胶质细胞而确立。
