CFB and Parkinson disease: Notably, these experiments revealed that the putative A1 genes CFB (the expression of which can promote the transformation of astrocytes into A1 phenotype by activating the complement system and promoting the formation of C3b [25]) and H2-T23 (H2-T23 is a mouse MHC-encoded gene that can present specific antigenic peptides and mediate immune responses, in the CNS, H2-T23 increases the expression of IL-1β and TNF-α, mediated proinflammatory function of astrocytes [26]) remained highly expressed in MPTP-induced PD mice compared with the control group (Figure 7A,B).