Skin bacteria after chlorhexidine exposure--is there a difference in response to human β-Defensin-3?

M. Reichel (1, 2) , A. Heisig (2) , P. Heisig (2) , G. Kampf (1, 3)

1 BODE Chemie GmbH, Scientific Affairs
2 Department of Pharmaceutical Biology and Microbiology, Institute of Pharmacy
3 Institute for Hygiene and Environmental Medicine

We investigated whether exposure to sub-lethal concentrations of chlorhexidine digluconate (CHG) changed the response of five spp. to human β-Defensin-3 (hBD-3). The change in response for each strain was determined in vitro with time-kill experiments in suspension by comparing the mean log reduction caused by hBD-3 at 1.5 and 3 h in exposed and non-exposed bacteria. The identity of staphylococcal species was verified by DNA sequence homology in the genes in comparison with reference strains. Baseline sub-lethal concentrations allowing visible bacterial growth were between 0.0625 and 0.25 μg/ml. Sub-lethal CHG concentrations increased within 3 days in two isolates. For 19/2, CHG-exposed cells were less susceptible to 0.5 μg/ml hBD-3 (log reduction 0.78 versus 2.06 at 1.5 h;  < 0.001; -test). For , however, CHG-exposed cells were more susceptible to 1 μg/ml hBD-3. The observed changes between CHG-exposed and non-exposed cells did not indicate a general trend in response to hBD-3. Overall, we found no consistent evidence that 3 days of exposure to CHG changed the response of five spp. to hBD-3. The use of CHG for skin antisepsis is, based on our data, unlikely to change the natural defence activity of hBD-3.

Mots clés: Life Sciences

M. Reichel, A. Heisig, P. Heisig, G. Kampf. Skin bacteria after chlorhexidine exposure--is there a difference in response to human β-Defensin-3?. European Journal of Clinical Microbiology and Infectious Diseases, 2010, 29 (6), pp.623-632. ⟨10.1007/s10096-010-0904-4⟩. ⟨hal-00580338⟩