Reduction of vancomycin resistance inVanAand VanBcontainingVancomycin Resistant Enterococci (VRE) isolatesin presence of lactoferrin protein

The protein lactoferrin (LF) reduces the MIC of Antibiotic vancomycin for vancomycin-resistant enterococci isolates The purpose of this research was to investigate the effect of LF on the MIC of vancomycin for vanA and VanB resistant isolates of enterococci. In this experimental study, after isolating and identifying 265 strains of enterococci from clinical specimens, The MIC test by using E-test method was performed for the vancomycin resistance enterococci specimens with the vancomycin and teicoplanin antibiotics. Using, Real time PCR method to study the presence of vanA and vanB genes in vancomycin-resistant Enterococcus. Then the effect of lactoferrin on the MIC of VRE isolates was assessed and Using SPSS software version 20 (version 20, SPSS Inc., Chicago, IL) and linear regression and Pearson correlation test with significance level P-value <0.05 was analyzed. VanA isolate at (2048µg/ml) concentration of LF showed 85 and 80 fold reduced the MIC of vancomycin in modified Etest and Microtiter methods respectively and in vanB isolate at the concentration of (512µg/ml) of LF 10 and 10.3 fold reduced the MIC of vancomycin in modified Etest and broth Microtiter methods respectively. lactoferrin index showed a significant positive correlation with reduced vancomycin MIC (P<0.001 and r= 0.183). Different concentrations of Lactoferrin protein induced reduction in VRE isolates contained van A and van B genes in vivo concentrations suggest a potential use for this protein as an adjunctive agent to vancomycin.