CHI3L2 and glioma: In another study, the levels of AIF1 did not differ between the sexes in biopsied brains from AD patients, but were associated with age and correlated positively with chitinase-3-like protein 2 (CHI3L2), a glycoprotein secreted by macrophages, dendritic cells, osteoclasts and highly proliferative cells involved in the immune infiltration of gliomas [174,175].