MBP and Obesity: Therefore, to determine whether C1QA deficiency prevents obesity-induced phagocytic activity of microglia and myelin degradation, brain sections that contained a portion of the CA1 region of the hippocampus, corpus callosum, and cortex from 12-month WD-fed and CD-fed C1qa KO and WT mice were immunostained for IBA1 (myeloid cells marker), CD68 (lysosomes/phagosomes), and MBP (myelin basic protein).