Lymphostatin (lifA) of rabbit enteropathogenic Escherichia coli possesses both immunomodulation and adhesion properties
- VernacularTitle:兔肠致病性大肠杆菌lifA基因的免疫调节和黏附特性
- Author:
Chengru ZHU
;
Ying MAO
;
Shuzhang FENG
- Publication Type:Journal Article
- Keywords:
rEPEC;
lifA;
colonization
- From:
Chinese Journal of Veterinary Science
2009;29(5):603-609
- CountryChina
- Language:Chinese
-
Abstract:
The rabbit enteropathogenic E. coli (rEPEC) strain RDEC-1 possesses a lifA homologue adjacent to the LEE pathogenicity island. To study the entire nucleotide sequence and biological function of lifA,the DNA sequence and biological function of RDEC-1 lifA were analysed with gene cloning,gene knock-out and in vivo virulence examination. The result showed that the entire coding sequence of the lifA of RDEC-1 shares nearly absolute homology with the lifA of human isolates. RDEC-1 lifA inhibited IL-2 expression in stimulated rabbit peripheral blood mononuclear cells. We further demonstrated significant reduction in fecal bacterial shedding by RDEC-1 derivative lifA mutant when compared with its parent strain. In a competitive study when rabbits were inoculated with a combination of the WT and the mutant, the WT was the predominant bacteria recovered from fecal samples, while fewer mutant bacteria were recovered. However,the lifA mutant is able to induce A/E type of lesions as efficient as the parent strain. The data provide direct evidence that lifA of rEPEC plays a role in immunomodulation and in in vivo colonization in the intestinal tract.
