AIM To develop a novel Helicobacter pylori(H.pylori)CagA antibody enzyme-linked immunosorbent assay(ELISA)suitable for detecting serum anti-CagA antibodies with high sensitivity.METHODS Recombinant East Asian-type Cag...AIM To develop a novel Helicobacter pylori(H.pylori)CagA antibody enzyme-linked immunosorbent assay(ELISA)suitable for detecting serum anti-CagA antibodies with high sensitivity.METHODS Recombinant East Asian-type CagA protein was purified and immobilized for ELISA.Serum samples from 217Vietnamese individuals(110 H.pylori-infected and107 uninfected individuals)were applied.Conventional ELISA from Western-type CagA and our East Asian-type CagA ELISA were evaluated by comparing 38 subjects with the Western-type genotype and 72 subjects with the East Asian-type cagA genotype.Histological scores of the gastric mucosa were determined using the updated Sydney System to examine the relationship with anti-CagA antibody titers.RESULTS Recombinant 70-100 k Da fragments were immobilized on the ELISA plate.In ROC analysis,the area under the curve of our East Asian-type CagA ELISA was comparable to that of conventional CagA ELISA.The sensitivity of the two ELISAs differed depending on the cagA genotype.The sensitivity of East Asian-type Cag A ELISA was higher for subjects infected with East Asiantype cagA H.pylori(P<0.001),and the sensitivity of the conventional CagA ELISA tended to be higher for subjects infected with Western cagA H.pylori(P=0.056).The titer of anti-CagA antibody tended to correlate with monocyte infiltration scores(r=0.25,P=0.058)and was inversely correlated with H.pylori density(r=-0.26,P=0.043).CONCLUSION The novel ELISA is useful to detect anti-CagA antibodies in East Asian countries,and the titer may be a marker for predicting chronic gastritis.展开更多
基金the National Institutes of Health,No.DK62813Grants-in-Aid for Scientific Research from the Ministry of Education,Culture,Sports,Science,and Technology of Japan(in part),No.25293104,No.26640114 and No.15H02657)theJapan Society for the Promotion of Science Institutional Program for Young Researcher Overseas Visits and the Strategic Funds for the Promotion of Science and Technology from the Japan Science and Technology Agency
文摘AIM To develop a novel Helicobacter pylori(H.pylori)CagA antibody enzyme-linked immunosorbent assay(ELISA)suitable for detecting serum anti-CagA antibodies with high sensitivity.METHODS Recombinant East Asian-type CagA protein was purified and immobilized for ELISA.Serum samples from 217Vietnamese individuals(110 H.pylori-infected and107 uninfected individuals)were applied.Conventional ELISA from Western-type CagA and our East Asian-type CagA ELISA were evaluated by comparing 38 subjects with the Western-type genotype and 72 subjects with the East Asian-type cagA genotype.Histological scores of the gastric mucosa were determined using the updated Sydney System to examine the relationship with anti-CagA antibody titers.RESULTS Recombinant 70-100 k Da fragments were immobilized on the ELISA plate.In ROC analysis,the area under the curve of our East Asian-type CagA ELISA was comparable to that of conventional CagA ELISA.The sensitivity of the two ELISAs differed depending on the cagA genotype.The sensitivity of East Asian-type Cag A ELISA was higher for subjects infected with East Asiantype cagA H.pylori(P<0.001),and the sensitivity of the conventional CagA ELISA tended to be higher for subjects infected with Western cagA H.pylori(P=0.056).The titer of anti-CagA antibody tended to correlate with monocyte infiltration scores(r=0.25,P=0.058)and was inversely correlated with H.pylori density(r=-0.26,P=0.043).CONCLUSION The novel ELISA is useful to detect anti-CagA antibodies in East Asian countries,and the titer may be a marker for predicting chronic gastritis.