CHOROID-PLEXUS - THE MAJOR SITE OF MESSENGER-RNA EXPRESSION FOR THE BETA-TRACE PROTEIN (PROSTAGLANDIN-D SYNTHASE) IN HUMAN BRAIN

Expression of beta-trace protein (beta-trace), recently identified as glutathion-independent prostaglandin D synthase (prostaglandin-H-2 D-i somerase; EC 5.3.99.2), was localized in paraffin sections of the huma n brain by insitu hybridization using digoxigenin-labeled antisense cR NA probes. The mRNA for beta-trace was predominantly found in the epit helial cells of the choroid plexus. Hybridization signals were also ob tained in some oligodendrocytes, particularly in the white matter. In the leptomeninges, specific signals were found in meningeal macrophage s and in single cells of the arachnoid barrier layer. The cells exhibi ting hybridization signals with the antisense cRNA probes for beta-tra ce were identified by counterstaining with antibodies directed against specific cell markers. Additionally, beta-trace mRNA was localized in tubular epithelial and basal cells of the human epididymis and in dif ferent cell types within the seminiferous epithelium of the testis.