Impaired monocyte macrophages function in patients with Crohn's disease.

To investigate the monocyte/macrophages function in patients with Crohn's disease (CD), phagocytosis, monocyte polykaryon formation and accessory cell function were studied. The number of yeast particles/monocyte in patients with CD was significantly higher (p less than 0.005) than that in healthy donors (HD). A significant increase (p less than 0.01) of fusion index was shown in CD patients in the absence of recombinant gamma-interferon (IFN gamma), while only a small amount of fusion was seen in HD. Accessory cell function of the monocytes from patients with CD was reduced, but 3H-thymidine incorporation was increased when the lymphocytes from patients with CD were cultured with the monocytes from HD. These results suggest that peripheral blood monocytes from patients with CD have abnormal functions, which may be involved in the pathogenesis of the granuloma and giant cell formation in CD patients.