Monocyte Aggregation and Multinucleated Giant-Cell Formation in Vitro in Crohn's Disease: The Effect of Cell Adhesion Molecules

Abstract

Background: Multinucleated giant-cell (MGC) formation is a common histopathologic feature of various granulomatous diseases, including Crohn's disease (CD). Methods: We have investigated monocyte aggregation and subsequent MGC formation by in vitro culturing peripheral monocytes from 25 CD patients, 15 ulcerative colitis (UC) patients, and 10 healthy controls. The effect of cell adhesion molecules on the monocyte aggregation and MGC formation in CD patients was investigated by using anti-β₂ integrin and anti-ICAM-1 antibodies. Results: The monocyte aggregation and MGC formation were significantly higher in CD than those seen in UC and controls (p < 0.05). In CD, antibody to β₂ integrin could inhibit not only the monocyte aggregation but also the subsequent MGC formation. In contrast, the antibody to ICAM-1 could inhibit the monocyte aggregation; however, it could not inhibit the MGC formation. Conclusions: Monocyte aggregation and MGC formation are increased in CD. β₂ Integrin may play an important role in the monocyte aggregation and MGC formation of CD patients.

Key Words:

• Adhesion molecules
• aggregation
• Crohn's disease
• monocyte
• multinucleated giant cell