CD74 and brain ischemia: Given that CD74 expression was nearly undetectable in microglia from the Sham group but markedly elevated in microglia from the MCAO/R group, where microglia exhibited a pro-inflammatory phenotype (Fig. 6A-C), we further examined the effect of CD74 knockdown in microglia on the levels of key inflammatory factors following cerebral ischemia-reperfusion.