Mucosal humoral immune response toHelicobacter pylori in patients with duodenitis

Abstract
The humoral immune response toHelicobacter pylori infection in the duodenum has been investigated by short-termin vitro culture, ELISA, and immunoblotting techniques.H. pylori IgA secretion by duodenal bulb biopsies was significantly increased (PH. pylori in patients with duodenitis was restricted to the first part of the duodenum; second part duodenal biopsies secreting significantly (Pin vitro. H. pylori IgG antibody secretion by cultured biopsies was also significantly increased (PH. pylori infection but without duodenitis. Immunoblotting of duodenal bulb culture supernatants showed positive recognition by the mucosal IgA response ofH. pylori antigens in the region of 120, 90, 61, and 31–26 kDa in patients with duodenitis. Serologically, such patients showed little evidence of IgAH. pylori antibodies by immunoblotting. These results demonstrate that the inflammatory response in the duodenal mucosa of patients with duodenitis represents a specific highly localized humoral response toH. pylori.