Abnormal Proportion of γδ T Cells in Peripheral Blood Is Frequently Detected in Patients With Periodontal Disease

T he proportions of γδ T cells in the peripheral blood of 8 early‐onset periodontitis (EOP) patients, 8 later‐onset periodontitis (LOP) patients, and of 17 healthy subjects (HS) were assessed by immunofluorescence assay using an anti‐pan γ δ T cell monoclonal antibody (TCR‐81) to study the population attributes of peripheral blood γ σ T cells in patients with periodontal disease. The distribution of the proportions of γ δ T cells in both EOP and LOP patients was found to be one and one half times broader than that in the HS; however, there was no significant difference in the proportion of γ δ T cells between each group. An abnormally high proportion of peripheral blood γ δ T cells in pan T cells (>9.90%) was observed in 37.5% of both the EOP patients and the LOP patients. An abnormally low proportion (<5.57%) was observed in 50% of the EOP patients and in 25% of the LOP patients. The higher occurrences of the high or low γ δ T cell proportions were significant between EOP and HS, and between EOP + LOP and HS. There was no correlation between the proportion of γδ T cells and age or the clinical parameters of periodontal status. It was concluded that an abnormal proportion of γδ T cells is frequently detected in patients with periodontal disease. These findings are consistent with the proposed role of the γ δ T cells for playing a unique role as a first line defense against infections at body surfaces. J Periodontol 1993; 64:963–967.