Immunohistochemical determination of age related proliferation rates in normal and benign hyperplastic human prostates.

To study whether benign prostatic growth in aging men correlates with an increase in proliferation, proliferation rates were determined immunohistochemically using the antibody Ki-67 in 20 benign hyperplastic prostates (BPH) and in four normal prostates (NPR). There was no significant correlation between age and proliferation rate in epithelium or stroma in BPH. In addition, no significant correlation between prostate weight and proliferation rate could be demonstrated in either compartment. In NPR the proliferation rate in epithelium and stroma was 9 times and 37 times lower, respectively, than in BPH. Obviously the induction of BPH from NPR may be associated with a distinct increase in proliferation. The further increase in BPH volume, however, is not correlated with a further increase in proliferation rate.

The transfer of bovine J blood group activity to erythrocytes: chemical nature of transferable and of non-transferable J.

The bovine J blood group substance exists as a glycosphingolipid (ceramide decahexoside as well as ceramide dodecahexoside) and as a glycoprotein. The lipidic form occurs in erythrocyte membranes, both forms are found in serum. The lipidic J substances were isolated from erythrocytes and from serum, and identified by thin-layer chromatography with lipidic J substances isolated from spleen. The glycoprotein nature of the non-lipidic J of serum was evident by pronase-catalysed hydrolysis yielding J-active glycopeptides of lower molecular weights. The lipidic J was completely extracted from lyophilized stroma with chloroform/methanol. From lyophilized serum, however, it was completely extracted only in the presence of water, indicating different binding partners in serum and in erythrocyte membranes. The J lipid was incorporated as intact molecule into the erythrocyte membrane by a simple incubation technique. The incorporation was inhibited by various glycerophospholipids (called blockers). The J glycoprotein could not be transferred to the erythrocyte membrane. Three methods are described which are suitable for the preparation of a blocker-free fraction enriched with J lipids from J-positive serum.

Chemical characterization of porcine blood serum components with A and SLA activity.

The porcine A blood group substance is found in the serum as a lipid and, additionally, in certain animals, as a glycoprotein. Swine lymphocyte antigens (SLA) occur in the serum only as glycoproteins. Heat treatment of the solid residue obtained by lipid extraction yielded a water-soluble fraction with low protein content, high A activity, but no SLA activity. Poly(glycosyl)ceramides with SLA activity do not occur in the serum; poly(glycosyl)ceramides with A activity cannot be excluded. Desialylation of protein fractions has no effect on A and SLA activity. Both A and SLA activities of protein fractions are stable to mild alkaline hydrolysis thus indicating N-glycosidic carbohydrate-peptide linkages.