CD39 expression on T lymphocytes correlates with severity of disease in patients with chronic lymphocytic leukemia

Introduction: Chronic lymphocytic leukemia (CLL) is a B-cell disorder, but it is also associated with abnormalities in T-lymphocyte function. In this study we examine changes in T-lymphocyte CD39 and CD73 expression in patients with CLL. Methods: Blood samples were drawn from 34 patients with CLL and 31 controls. The cells were stained for CD3, CD4, CD8, CD19, CD39, and CD73 and analyzed by flow cytometry. Results: Overall, patients with CLL had a higher percentage of CD39+ T lymphocytes than did controls. The percentage of cells expressing CD39 was higher in both CD4+ cells and CD8+ cells. Higher CD3/CD39 expression was associated with a later disease stage. No correlations between T-lymphocyte CD39 levels and CD38 or Zap-70 expression were observed. In contrast, the percentage of T lymphocytes and B lymphocytes that expressed CD73 was decreased in patients with CLL. Average B-lymphocyte CD73 expression was decreased in CLL because the majority of CLL clones were CD73. However a minority of CLL clones were CD73+, and patients with CD73+ clones tended to have earlier stage disease. Conclusion: T-lymphocyte CD39 and CD73 expression may be useful prognostic markers in patients with CLL. Expression of CD73 on the malignant cell population in CLL may be a marker of better prognosis.