Differentiation of T lymphocyte subpopulations, macrophages, and HLA-DR-restricted cells of apical granulation tissue

Abstract

Sixteen specimens excised from apical granulation tissue were examined for immunocompetent T lymphocytes, mononuclear phagocytes, and HLA-DR-determined cells. Light microscopic visualization of the cells was performed using monoclonal antibodies and the immunocytochemical alkaline phosphatase anti-alkaline phosphatase technique. Quantitative assessment of the biopsy specimens showed that in five diagnosed cysts, eight granulomas, and three specimens taken from scar tissue, macrophages represented the dominating inflammatory cell fraction, followed by T lymphocytes. In the latter group, helper/inducer T cells were most frequent. Cysts showed a statistically significant increase in cell populations of helper/inducer, suppressor/cytotoxic T cells, macrophages, and HLA-DR-coded cells. There were only a few activated T lymphocytes.