悪性リンパ腫におけるＬＦＡ‐１分子発現の免疫組織学的検討

Abstract

Lymphocyte function-associated antigen-1 (LFA-1), a heterodimer glycoprotein consisting of α and β chains, belongs to a integrin superfamily and is known to distribute widely on lymphohemopoietic cells. In this study, we investigated LFA-1 expression in 52 cases of non-Hodgkin's lymphoma and 32 cases of reactive lymphoproliferative disease using an immunohistochemical method. The proportion of LFA-1 positive cells among mononuclear cells in all specimens was scored as follows: grade 0 (0∼10%), grade 1 (10∼50%), grade 2 (50∼80%). and grade 3 (80∼100%). In reactive lymphoproliferative diseases, none of the cases belonged to the category of grade 0 or 1, and more than 80% were classified as grade 3. In contrast, more than 50% of non-Hodgkin's lymphomas were scored as grade 0 or 1. Therefore monoclonal antibodies to LFA-1 may be the useful antibodies for the evaluation of malignancy in lymphoproliferative diseases. We found no correlation between histological classification and LFA-1 expression of B cell lymphomas, and there was a tendency that T cell lymphomas were classified in higher grade than B cell lymphomas. In some cases, we analysed LFA-1 expression by flow cytometry. By this method, a small number of LFA-1 negative lymphoma cells among many LFA-1 positive normal lymphocytes could be exactly identified.So, flow cytometric analysis is necessary for the exact and objective evaluation of LFA-1 expression.