| Abstract: | Objective: The aims of this research were to purify and identify the 130 kDa (CagA) protein ofH. pylori clinical isolate HP97002 and evaluate the relationships between the purified 130 kDa (CagA) protein and gastric diseases.
Methods: The procedure for isolating the protein included 6 mol/L guanidine extract, size exclusion chromatography and elusion
from gel. Sera of 68 patients with gastric diseases (44 with chronic gastritis, 15 with atrophic gastritis, 7 with peptic
ulcer disease, 2 with gastric cancer) were obtained, and the serological response to CagA was studied by Western-blot using
the purified protein. Results: The purified protein was 130 kDa and preserved good antigenicity and revealed basic isoelectric
point about of 8.1. Among 68 sera, 43 sera could recognize the purified protein associated with chronic gastritis 47.7% (21/44),
atrophic gastritis 86.7% (13/15), peptic ulcer disease 100% (7/7), gastric cancer 100% (2/2). Compared with each other, the
difference was significant (χ2=13.327,P=0.004), and 130 kDa (CagA) protein was associated with severe gastric diseases (r
s=0.442,P=0.001). Conclusion: The 130 kDa (CagA) protein was associated with severe gastric diseases.
Project supported by the China Medical Board (96-628) and Zhejiang Province Hygiene Bureau (2000 A055) |
