DETECTION OF THE KI-67 PROLIFERATION-ASSOCIATED NUCLEAR ANTIGEN IN NORMAL CANINE LYMPHOID LYMPH-NODE CELLS BY THE USE OF THE MONOCLONAL-ANTIBODY MIB-1

This report describes the immunohistochemical detection of the Ki-67 p roliferation-associated nuclear antigen by means of MIB-1 monoclonal a ntibody (Ab) in paraffin tissue sections from 59 formol-fixed canine r eactive lymph nodes. In all the samples, the MIB-1 Ab strongly stained the nuclei, and especially the nucleoli, of nearly all the centroblas ts and pre-centroblasts in the dark zone of the germinal centers as it does in their human counterparts. On the other hand, the nuclei of th e cells of the paracortical T zone of the follicular mantle and of the marginal zone were not found to react with MIB-1.