PARACORTICAL POST-CAPILLARY VENULES OF HUMAN LYMPH NODES WITH SPECIAL REFERENCE TO THE DISTRIBUTION OF THEIR ENDOTHELIAL IgG

Abstract

The distribution of lgG in the endothelium of the

paracortical post-capillary venules (PCV) of human

lymph nodes was studied in frozen sections by

using an indirect immunoperoxidase technique.

Three different patterns of distribution could be

differentiated (luminal site, intraendothelial and

basement membrane site). Each of these patterns

was characteristically encountered in association

with one of three grades of PCV (graded on the

basis of the height of their endothelial cells). The

significance of this close relationship between the

IgG distribution and the changes in PCV endothelium

was discussed in regard to the T-lymphocyte

recirculation. A hypothesis was • introduced

describing the possible sequence of events involved

in the traversing of T-lymphocyte through the PCV

endothelium.