Effects of human serum and apo‐Transferrin on Staphylococcus epidermidis RP62A biofilm formation

Abstract

Biofilm‐associated Staphylococcus epidermidis infections present clinically important features due to their high levels of resistance to traditional antibiotics. As a part of human innate immune system, serum shows different degrees of protection against systemic S. epidermidis infection. We investigated the ability of human serum as well as serum component to inhibit the formation of, and eradication of mature S. epidermidis biofilms. In addition, the synergistic effect of vancomycin combined with apo‐Transferrin was checked. Human serum exhibited significant antibiofilm activities against S. epidermidis at the concentration without affecting planktonic cell growth. However, there was no effect of human serum on established biofilms. By component separation, we observed that antibiofilm effect of serum components mainly due to the proteins could be damaged by heat inactivation (e.g., complement) or heat‐stable proteins ≥100 kDa. In addition, serum apo‐Transferrin showed modest antibiofilm effect, but without influence on S. epidermidis initial adhesion. And there was a synergistic antibiofilm interaction between vancomycin and apo‐Transferrin against S. epidermidis. Our results indicate that serum or its components (heat‐inactivated components or heat‐stable proteins ≥100 kDa) could inhibits S. epidermidis biofilm formation. Besides, apo‐Transferrin could partially reduce the biofilm formation at the concentration that does not inhibit planktonic cell growth.

Antibiofilm efficacy of the gold compound auranofin on dual species biofilms ofStaphylococcus aureusandCandidasp.

“…in planktonic cells/biofilm single or dual culture was significantly enhanced in the presence of 10% C‐inactivated FBS (Table ). However, Ding et al () reported that even heat‐inactivated human serum can inhibit the biofilm formation of C. albicans ; we previously reported that the complement is the main antibiofilm component against S. epidermidis in human serum (She et al ). Similar to our results, Yin et al () reported that serum from burn‐injured rats increased S. aureus biofilm formation and induced bacterial aggregation and adherence to human fibronectin and fibrinogen by elevating oxidative stress.…”

Regulatory role of the RstB‐RstA system in adhesion, biofilm production, motility, and hemolysis

“…Biofilm production is a way by which bacteria protect themselves from the host immune system (She et al., ). However, whether rstA and rstB take part in biofilm formation remains undefined.…”

Contributions of the oligopeptide permeases in multistep of Vibrio alginolyticus pathogenesis

“…After adhesion to its host, bacteria are possible to start the invasion, besides they should try to protect themselves against the host immune system during this process. Therefore, various ways were developed, such as biofilm production (Atwood et al, 2015;Rybtke et al, 2015;She et al, 2016). Lee et al (2004) found that the oppA is involved in biofilm production of Vibrio fluvialis.…”