Endothelium-associated IgG in the post-capillary venules of the lymphatic tissues in mice bearing experimental neoplasia.

Post-capillary venules (PVC) of the lymph nodes and Peyer's patches were studied in frozen sections stained with an indirect immunoperoxidase technique to demonstrate their endothelium-associated IgG in DBA/2 mice bearing mastocytoma. The previously established three types of IgG-distribution (luminal, intraendothelial and basement membrane site), each confined to one of the three PCV grades (graded on the basis of the endothelial cell height), were found in these tumor-bearing mice, too. This finding shows that the tool applied in T-lymphocyte deprivation, be it a tumor or anti-theta-globulin, does not influence the behavior of this IgG-distribution profile. This fact lends further support to the thesis that the endothelium-associated IgG could be involved in the regulation of the T-cell passage through the wall of the post-capillary venules.