SEROLOGICAL AND CHROMATOGRAPHIC ANALYSES OF ANTIGENIC STRUCTURES DETECTED IN HUMAN-BRAIN, THYMUS AND LYMPH-NODES

Abstract

It is shown that the non-species-specific determinant of the antigenic thymus-brain system previously detected in murine and human brain also exists in human thymus. In contrast to the situation in mice and rats this antigenic structure is not expressed on suspended thymic lymphocytes, but is associated with thymic tissue largely depleted of thymic lymphocytes. This determinant is also detectable in human lymph nodes. Besides the non-species-specific antigenic determinant, human thymus and brain also share a species-specific determinant. In contrast to the non-species-specific determinant this structure is also displayed by suspended thymic lymphocytes, certain peripheral blood lymphocytes and bone marrow cells. The non-species-specific determinant detected in human thymus is borne by a structure which physico-chemically resembles the thymus-brain antigen isolated from murine brain and thymus and from human brain. Although the structure bearing the species-specific antigenic determinant has a similar apparent MW, both antigens could be separated by ion exchange chromatography, indicating their molecular diversity.