ABSTRACT
<p><b>OBJECTIVE</b>To investigate the infiltration of T lymphocytes with CD3 expression as surface marker and the activation of T lymphocytes with CD69 expression as activation marker.</p><p><b>METHODS</b>Nasal polyp tissue samples and peripheral blood were obtained from 21 patients. The normal inferior turbinate mucosa and peripheral blood were obtained as comparison. Flow cytometry was adopted to detect the expression of CD3 and CD69 of T lymphocytes.</p><p><b>RESULTS</b>Nasal polyp tissue consisted of abundant T lymphocytes. Activation marker CD69 was expressed in T lymphocytes of nasal polyps (36.96 +/- 2.50)% and peripheral blood (4.66 +/- 0.18)% from the same patient. The expression rates of CD69 after a short-term stimulation (5 h) in response to PDB were (59.88 +/- 2.59)% and (92.76 +/- 0.55)% respectively. While T lymphocytes was rarely detected in normal inferior turbinate and the expression of CD69 was low in peripheral blood from normal human but almost all T lymphocytes were activated after stimulation.</p><p><b>CONCLUSIONS</b>There were generous of T lymphocytes infiltrating in nasal polyps. The expression of CD69 in T lymphocytes was abnormally high, which indicated that T lymphocytes infiltrating in nasal polyps were in activated state immunologically.</p>