The relationship between persistent secretion of RANTES and residual infiltration of eosinophils and memory T lymphocytes after Helicobacter pylori eradication.

Helicobacter pylori (HP)-infected gastric mucosa displays a conspicuous infiltration of mononuclear cells as well as neutrophils. RANTES is a potent chemoattractant peptide for memory T lymphocytes and eosinophils. RANTES protein concentration and the numbers of RANTES-, CD45RO-, and major basic protein (MBP)-positive cells were therefore evaluated in the gastric mucosa from 51 patients with HP-positive chronic gastritis before and after HP eradication and from 22 HP-negative healthy volunteers. RANTES protein concentration was significantly elevated in HP-positive cases and remained high after HP eradication. The numbers of RANTES-, CD45RO-, and MBP-positive cells were significantly increased in HP-positive cases and were well correlated with RANTES protein levels. All tended to decrease after HP eradication, but did not reach the level of HP-negative cases, even at 24 months after HP eradication. It was concluded that persistent expression and secretion of RANTES were closely related to residual infiltration of memory T lymphocytes and eosinophils, for a prolonged period after HP eradication. This seems to be an important mechanism of prolonged gastric mucosal immune response against HP infection, even after HP eradication, and of persistent mucosal damage and atrophy.