The skin is colonized by a diverse array of microorganisms including bacteria and fungi. The bacterium-fungal interaction is found in many parts of the human body including the oral cavity and gastrointestinal tract. Interaction between species of one common genus is observed in propionibacteria. The distribution of different Propionibacterium strains is significantly different on the skin of healthy subjects in comparison to acne-affected skin indicating a possible communication between bacterial strains. Co-culturing the Trichophyton rubrum (T. rubrum) (108 CFU/ml) with commensal Staphylococcus epidermidis (S .epidermidis) (108 CFU/ml) in presence of glycerol showed the production of short chain fatty acids (SCFAs) by fermentation of glycerol. We found that S. epidermidis interfered with the growth of T. rubrum. In co-culture of S. epidermidis and Propionibacterium acne (P. acnes), P. acnes growth was inhibited by production of SCFAs via the sucrose fermentation of S. epidermidis. In vivo studies showed that S. epidermidis sucrose fermentation can ameliorate the P. acnes-induced macrophage inflammatory protein-2 (MIP-2) production in the mouse ear. Additionally, P. acnes colonization and inflammation of mouse ear were significantly reduced by using monoclonal antibodies to P. acnes.
Keywords: T. rubrum, S. epidermidis, P. acnes, SCFA, monoclonal antibody.