Recombinant HpaA purified from Escherichia coli has biological properties similar to those of native Helicobacter pylori HpaA.
The aim of this study was to recombinantly produce and purify Helicobacter pylori adhesin A (HpaA) from Escherichia coli and compare it to purified native H. pylori HpaA, for potential use as a vaccine antigen. The hpaA gene was cloned from H. pylori, transferred to two different expression vectors, and transformed into E. coli. Expression of rHpaA was analysed by immunoblot, inhibition ELISA, and semi-quantitative dot-blot. Using affinity chromatography, rHpaA was purified from E. coli and native HpaA from H. pylori. The binding of both purified proteins to sialic acid was analysed and antibody titres to native and rHpaA were compared after intraperitoneal immunisation of C57/Bl mice. The rHpaA protein was highly expressed in E. coli from both vectors. Purified recombinant and native HpaA bound similarly to fetuin but also to the non-sialylated asialofetuin. Both native HpaA and rHpaA induced comparable amounts of specific antibodies in serum after immunisation and they were identical in double immunodiffusion. In conclusion, rHpaA was successfully produced in E. coli. Purified rHpaA showed biological properties similar to those of native HpaA isolated from H. pylori and may therefore be further used as an antigen in the development of a vaccine against H. pylori infection.
Lundstrom
Anneli  M
A
Department of Medical Microbiology and Immunology, Göteborg University, Sweden. anneli.lundstrom@microbio.gu.se
Bolin
Ingrid
I
Bystrom
Mona
M
Nystrom
Susanne
S
D018829:Adhesins, Bacterial / Q000235:genetics / Q000276:immunology* / Q000378:metabolism* / Q000494:pharmacology; D000818:Animals; D000907:Antibodies, Bacterial / Q000096:biosynthesis / Q000097:blood; D000911:Antibodies, Monoclonal / Q000276:immunology; D015153:Blotting, Western; D002846:Chromatography, Affinity; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004797:Enzyme-Linked Immunosorbent Assay; D004926:Escherichia coli / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D005260:Female; D016480:Helicobacter pylori / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D007114:Immunization; D005779:Immunodiffusion; D051379:Mice; D008810:Mice, Inbred C57BL; D019158:N-Acetylneuraminic Acid / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology; D000509:alpha-Fetoproteins / Q000276:immunology / Q000378:metabolism
D018829:Adhesins, Bacterial; D000907:Antibodies, Bacterial; D000911:Antibodies, Monoclonal; D004269:DNA, Bacterial; D011994:Recombinant Proteins; D000509:alpha-Fetoproteins; C095977:adhesin A, Helicobacter; D019158:N-Acetylneuraminic Acid