Lactobacillus inhibit adhesion of Staphylococcus aureus to HeLa cells / 生物工程学报

ABSTRACT

To assess the ability of the previously selected human vaginal isolates of Lactobacillus crispatus (L. crispatus) T79-3, T90-1 and Lactobacillus jensenii (L. jensenii) T118-3, T231-1 to inhibit the growth of Staphylococcus aureus and block their adhesion to HeLa cells. The inhibitory bioactive substances produced by these Lactobacillus were also identified. Inhibitory substances interaction tests were carried out by using a streak-diffusion method on agar plates. Three types of interaction were performed to determine the inhibitory effect of Lactobacillus on adhesion of Staphylococcus aureus to HeLa cells Exclusion Group (Lactobacillus and HeLa followed by pathogens), Competition Group (Lactobacillus, HeLa and pathogens together) and Displacement Group (pathogens and HeLa followed by the addition of Lactobacillus). The number of HeLa cells adhered to Staphylococcus aureus was quantified by bacteria colony counts on LB plate. The results showed that lactic acids produced by the Lactobacillus are the main substances that can inhibit Staphylococcus aureus growth and there is variation among the three types of interaction regarding the inhibitory activity against Staphylococcus aureus. The effects of Lactobacillus on blocking the adhesion to HeLa cells were concentration dependent. All four Lactobacillus isolates displayed the ability to inhibit Staphylococcus aureus growth and block Staphylococcus aureus adherence to HeLa cells. Exclusion Group was the most effective, and T79-3 showed greater capacity to block Staphylococcus aureus adherence compared with the other three isolates. The present study suggests the potential ability of L. crispatus T79-3 as probiotic for the treatment and prevention of urogenital infections in women.