Infection with CagA-positive Helicobacter pylori strain containing three EPIYA C phosphorylation sites is associated with more severe gastric lesions in experimentally infected Mongolian gerbils (Meriones unguiculatus)

• Main Authors: M. Ferreira Júnior, S.A. Batista, P.V.T. Vidigal, A.A.C. Cordeiro, F.M.S. Oliveira, L.O. Prata, A.E.T. Diniz, C.M. Barral, R.C. Barbuto, A.D. Gomes, I.D. Araújo, D.M.M. Queiroz, M.V. Caliari
• Format: Article
• Language: English
• Published: PAGEPress Publications 2015-04-01
• Series: European Journal of Histochemistry
• Subjects: Gastritis; atrophy; intestinal metaplasia; dysplasia; Mongolian gerbil; cagA EPIYA C motif.
• Online Access: http://ejh.it/index.php/ejh/article/view/2489

<p>Infection with <em>Helicobacter pylori</em> strains containing high number of EPIYA-C phosphorylation sites in the CagA is associated with significant gastritis and increased risk of developing pre-malignant gastric lesions and gastric carcinoma. However, these findings have not been reproduced in animal models yet. Therefore, we investigated the effect on the gastric mucosa of Mongolian gerbil (<em>Meriones unguiculatus</em>) infected with CagA-positive <em>H. pylori</em> strains exhibiting one or three EPIYA-C phosphorilation sites. Mongolian gerbils were inoculated with <em>H. pylori </em>clonal isolates containing one or three EPIYA-C phosphorylation sites. Control group was composed by uninfected animals challenged with Brucella broth alone. Gastric fragments were evaluated by the modified Sydney System and digital morphometry. Clonal relatedness between the isolates was considered by the identical RAPD-PCR profiles and sequencing of five housekeeping genes, <em>vac</em>A i/d region and of <em>oip</em>A. The other virulence markers were present in both isolates (<em>vac</em>A s1i1d1m1, <em>ice</em>A2, and intact <em>dup</em>A). CagA of both isolates was translocated and phosphorylated in AGS cells. After 45 days of infection, there was a significant increase in the number of inflammatory cells and in the area of the <em>lamina propria</em> in the infected animals, notably in those infected by the CagA-positive strain with three EPIYA-C phosphorylation sites. After six months of infection, a high number of EPIYA-C phosphorylation sites was associated with progressive increase in the intensity of gastritis and in the area of the <em>lamina</em> <em>propria</em>. Atrophy, intestinal metaplasia, and dysplasia were also observed more frequently in animals infected with the CagA-positive<em> </em>isolate with three EPIYA-C sites.  We conclude that infection with <em>H. pylori</em> strain carrying a high number of CagA EPIYA-C phosphorylation sites is associated with more severe gastric lesions in an animal model of <em>H. pylori</em> infection.</p>