Demonstration of cells of the mononuclear phagocyte lineage in the periodontium following experimental tooth movement in the rat. An immunohistochemical study using monoclonal antibodies ED1 und ED2 on paraffin-embedded tissues.

In this immunohistochemical study two monoclonal antibodies, ED1 and ED2, which recognize exclusively cells of the mononuclear phagocyte system (MPS) in the rat, were applied to study the presence of these cells during remodeling of the periodontal tissues following mechanically induced orthodontic tooth movement. The immunohistochemical procedure was carried out successfully on routinely processed, paraffin-embedded histological sections using the avidin-biotin-peroxidase-complex (ABC) technique. Cells of the MPS could be demonstrated on positive control sections of rat spleen and bone marrow. For the study of remodelling of the periodontal tissues only the ED1 antibody proved to be suitable. With this antibody, positive mononuclear and multinuclear cells, i.e. macrophages and osteoclasts, were seen throughout the periodontium even in the control animals. After the induction of orthodontic tooth movement activation of macrophages, osteoclasts and odontoclasts was demonstrable, all of them showing a clear-cut positive reaction to ED1.