Which virulence factor is involved in Vibrio cholerae adherence to intestinal cells?

• A. Mucinase
• B. Pili-mediated adherence
• C. Endotoxin LPS
• D. Capsule formation with Vi antigen

Answer: (B)

Understanding how Vibrio cholerae attaches to intestinal cells is essential because initial adherence to the mucosal surface is the first step in colonization and subsequent toxin delivery. The factor that mediates this attachment is pili-mediated adherence, specifically the toxin-coregulated pilus, a type IV pilus that allows the bacteria to adhere strongly to enterocytes in the small intestine. This adherence sets the stage for colonization and the production of cholera toxin.

Mucinase breaks down mucin to help movement through the mucus but doesn’t provide tight binding to cells. Endotoxin LPS drives inflammatory and secretory responses but isn’t an adherence apparatus. Capsule formation with Vi antigen is associated with other pathogens (notably Salmonella Typhi) and isn’t the mechanism Vibrio cholerae uses to adhere.