Contribution of major histocompatibility complex genes to susceptibility and resistance in Helicobacter pylori related diseases

Background/Aim Although there have been numerous reports concerning the vir ulence factors of isolates for investigating the pathogenesis of Helicobact er pylori infection, few studies have been carried out regarding the associ ation of HLA class II genes of the host with H. pylori related diseases. Tw o published studies have only analysed the HLA DQ locus alone. The aim of t his study was thus to determine the association of HLA class II genes (DR, DQ and DP) with H. pylori related diseases using the DNA typing method. Methods Fifty-eight patients with H. pylori positive gastric ulcers, 44 pat ients with H. pylori positive duodenal ulcers, 45 patients with H. pylori p ositive gastritis and 34 healthy subjects without H. pylori infection were typed for HLA class II genes by means of DNA typing with the polymerase cha in reaction-sequence specific oligonucleotide probes method. Results A negative association with DRB1*1501, DQA1*01021 and DQB1*0602 all eles was noted in all three of the patient groups studied. Compared with th e healthy controls, a positive association with DPA1*0201 (P = 0.032) and D PB1*0901 (P = 0.005) in gastric ulcers, a positive association with DRB1 *0 405 (P = 0.022) and DQB1*0401 (P = 0.044) in duodenal ulcers, and a positiv e association with DPB1*0901 (P = 0.016) in gastritis were observed. A hapl otype analysis showed that the association of alleles with H. pylori relate d disease was with the haplotype rather than with either of the alleles ind ividually. After correction for multiple comparisons, all the significant a ssociations obtained between H, pylori related diseases and HLA class II ge nes disappeared. Conclusions The interplay between host immunogenetic factors, bacterial vir ulence factors and environmental conditions may thus play a more important role in the outcome of H. pylori infection than immunogenetic factors alone , Eur J Gastroenterol Hepatol 11:875-880 (C) 1999 Lippincott Williams & Wil kins.