Yee K T, Smetanka A M, Lund R D, Rao K
Department of Neurobiology, Anatomy and Cell Science, School of Medicine, University of Pittsburgh, PA 15261.
Brain Res. 1990 Oct 15;530(1):121-5. doi: 10.1016/0006-8993(90)90667-z.
Cells expressing major histocompatibility complex (MHC) antigens are rarely found in normal mature brains, but cells resembling microglia can be induced to express these antigens following the onset of neural degeneration. In young rats, these cells show spontaneous expression of class I MHC antigens, which is further enhanced in the superior colliculus by the degeneration resulting from eye removal. By contrast, class II MHC antigen expression does not occur spontaneously and can only be induced by eye removal when the lesion is performed after the first postnatal week, when the optic tract begins to myelinate. We suggest that different signals are responsible for induction of class I and of class II MHC antigen expression.
表达主要组织相容性复合体（MHC）抗原的细胞在正常成熟大脑中很少见，但在神经变性开始后，类似小胶质细胞的细胞可被诱导表达这些抗原。在幼鼠中，这些细胞显示出I类MHC抗原的自发表达，通过摘除眼球导致的变性，这种表达在上丘中进一步增强。相比之下，II类MHC抗原表达不会自发发生，只有在出生后第一周后进行摘除眼球手术（此时视束开始髓鞘化）时，才能由摘除眼球诱导产生。我们认为，不同的信号负责诱导I类和II类MHC抗原的表达。
