Antigenic Constituents of Human Cortical Grey Matter

Abstract

RECENT work in this laboratory has been directed towards the development of improved methods for the extraction of proteins of human brain, and their chemical and immunological characterization. Thus Bogoch, Rajam and Belval¹ have demonstrated a large number of protein entities in an extract of low ionic strength of human cortical grey matter. This extract (A) was prepared by cold homogenization in 0.005 M phosphate buffer, pH 7, and ultracentrifugation at 80,000g to yield a clear supernate. Chromatography of concentrated A on DEAE cellulose, using a gradient increasing in ionic strength and decreasing in pH, indicated the presence of at least fifteen main protein groups; that these chromatographic groups were heterogeneous was suggested by the results of assays for hexose, hexosamine, neuraminic acid and protein in each tube of chromatographic effluent as well as by electrophoretic findings. The total number of distinct or partially related proteins appeared to exceed a hundred. Supporting evidence, obtained in work on animal brain material, has been adduced by others².