[Vitamin A: effect on phagocytosis and neutrophil bactericidal systems under normal conditions and in various...

Effect of vitamin A on phagocytic activity and the state of bactericide system involving myeloperoxidase and cationic proteins was studied in neutrophils from peripheric blood of volunteers and of the patients with chronic pneumonia and lung cancer. Vitamin A was administered per os within 1 week at a daily dose of 500,000 IU. In healthy persons vitamin A, not affecting the ability of neutrophils to capture and lyse microbes, activated myeloperoxidase and increased the cationic proteins content. Under conditions of lung cancer the vitamin did not alter any patterns of phagocytosis studied. Vitamin A did not affect the capture and lysis of microbes in chronic pneumonia but increased distinctly the myeloperoxidase activity in neutrophils, impaired during the disease, and normalized partially the content of cationic proteins.