Antigenicity of fetal and adult cerebral tissue of man

Antisera in rabbits were prepared with extracts of cerebral tissue of the human fetus and adult. Two brain-specific antigens were detected. One was specific for adult brain after absorption of the antiserum with other adult tissues. The other antigen was common to both fetal and adult brain. All antigens detected in fetal cerebrum also were present in extracts of fetal cerebellum and brain stem. An antigen occurring only in fetal brain was not detected, but an antigen specific for liver in fetal life was demonstrated in adult tissues, including brain, liver, spleen, kidney, and intestine.