Study objective: To determine whether or not the levels of gamma/delta lymphocytes increase in bronchoalveolar lavage (BAL) fluid from patients with pulmonary tuberculosis.
Design: Prospective data collection relating to cells in BAL fluid and peripheral blood mononuclear cells (PBMC) from patients with pulmonary tuberculosis and control subjects.
Setting: A university hospital, from March 1990 to December 1993.
Patients: Thirteen patients with pulmonary tuberculosis who were diagnosed by culture of Mycobacterium tuberculosis from their sputum of BAL fluid and/or clinical response were enrolled in the study. Fifteen healthy volunteers participated as control subjects.
Measurements and results: The differential cell counts in BAL fluid were made by Diff-Quik stain. The percentages of T-cell receptor (TCR) (gamma/delta and alpha/beta)-positive lymphocytes and interleukin 2 (IL-2) receptor-positive CD3 lymphocytes in BAL fluid and peripheral blood were measured by dual scan with flow-cytometry. The percentage and absolute number of lymphocytes and the percentages of CD3+, IL2R+ lymphocytes in BAL fluid significantly increased in patients with tuberculosis when compared with those of control subjects. The percentages and numbers of gamma/delta and alpha/beta TCR-positive lymphocytes in BAL fluid and PBMC from patients with tuberculosis and indistinguishable from those of control subjects.
Conclusions: gamma/delta Lymphocytes do not appear to have as much meaning in patients as they do in animal studies.