A study of T and B cells in pulpal pathosis

A study was undertaken using monoclonal antibodies to determine the types of lymphocytes present in pulpal tissues. Pulps were extirpated from teeth clinically diagnosed as normal, reversibly inflamed, or irreversibly inflamed and stained with hematoxylin and eosin and an indirect immunoperoxidase technique using monoclonal antibodies reactive to pan-B lymphocytes (B), pan-T lymphocytes (T1), and helper (T4) and suppressor (T8) T lymphocytes. T and/or B lymphocytes were observed in normal pulpal tissues with T8 lymphocytes being predominant. The pulpal tissue in the reversible group demonstrated that more than 90% of the lymphocyte population were T lymphocytes, with a T4/T8 ratio of 0.56. Higher numbers of T1, T4, T8; and B lymphocytes were observed in the pulp from teeth in the irreversible group. A ratio of 1.14 of T4/T8 lymphocytes was observed in the irreversible group. A B/T1 lymphocyte ration of 1.60 suggested this ratio might be used as an index in the immunohistological diagnosis of irreversible pulpal pathosis. There appeared to be no association between the periodontal status of the teeth and the number of immunocompetent cells observed in the pulps. An hypothesis on the regulatory functions of T4 and T8 lymphocytes as well as the interaction of T and B lymphocytes and their products in the pathogenesis of pulpal disease is presented.