en Evaluation of Prevalence, Homology and Immunogenicity of Dispersin among Enteroaggregative Escherichia coli Isolates from Iran Related Fields Related Fields مقاله کامل Full Length/Original Article <p style="direction: ltr; "><strong>Background</strong>: Diarrhea, caused by enteroaggregative <em>Escherichia coli</em> (EAEC), is an important cause of illness and death. Numerous virulent factors have been described in EAEC. However, their prevalence was highly variable among EAECs of distinct geographic locations. Studies have shown that dispersin (antiaggregation protein, <em>aap</em>) is one of the important and abundant virulent factors in EAEC. In this study, we aimed to determine the presence, conservation and immunogenicity of <em>aap</em> gene in EAEC isolated from Iranian patients. <strong>Methods</strong>: PCR amplification of <em>aap</em> gene in the EAEC isolates was performed, and the <em>aap</em> gene was cloned in pBAD-gIIIA vector. The sequence of <em>aap</em> gene was analyzed using the ExPASy and BLAST tools. Expression of <em>aap</em> gene was performed in <em>E. coli</em> Top10, and expression confirmation was carried out by SDS-PAGE and Western-blot techniques. Rabbits were immunized with purified dispersin protein emulsified with Freund&rsquo;s adjuvant. Sera were collected and examined for antibody response. Finally, <em>in</em> <em>vitro</em> efficacy of dispersin and anti-dispersin was evaluated. <strong>Results</strong>: The results of PCR showed the presence of <em>aap</em> gene in all of the EAEC isolates with significant homology. Finally, the significant difference between the levels of IgG response in dispersin-injected rabbits and control group was observed. <strong>Conclusion</strong>: Our results were in accordance with other studies that reported the presence of dispersin in the EAEC isolates with high conservation and immunogenicity. Hence, dispersin could be a promising candidate for any probable prevention against EAEC infections.</p> Enteroaggregative E. coli, Diarrhea, Enzyme-linked immunosorbent assay 40 47 http://ibj.pasteur.ac.ir/browse.php?a_code=A-10-1-611&slc_lang=en&sid=1 Mohammad Reza Asadi Karam No Department of Molecular Biology, Pasteur Institute of Iran, Tehran, Iran Ali Akbar Rezaei No Department of Molecular Biology, Pasteur Institute of Iran, Tehran, Iran Seyed Davar Siadat No Department of Mycobacteriology and Pulmonary Research, Pasteur Institute of Iran, Tehran, Iran Mehri Habibi No Department of Molecular Biology, Pasteur Institute of Iran, Tehran, Iran Saeid Bouzari saeidbouzari@yahoo.com Yes Department of Molecular Biology, Pasteur Institute of Iran, Tehran, Iran