CR1-expression and C3b-mediated phagocytosis of granulocytes in purulent maxillary secretion and peripheral blood from patients with sinusitis.

Granulocytes in sinus pus and in peripheral blood in 28 patients with maxillary sinus empyema were compared to blood granulocytes obtained from healthy blood donors. A flow cytofluorometric assay technique was used to establish the C3b-mediated phagocytosis and the CR1-receptor expression. The results indicate that a subpopulation of viable granulocytes in situ was activated with an increased ability to ingest particles. From 11 of 28 patients, an increased CR1-expression was also demonstrated in the blood samples, reflecting a priming of the circulating granulocytes before extravasation.