The role played by antibiotic-producing strains of the normal human microflora in immune mechanisms of superficial infections is still uncertain. That such strains are extremely common in the ocular flora1-4 as well as in the intestinal tract,5-9 skin,10-12 nose and throat,13,14 and oral cavity15,16 has now been well established. The general characteristics of a number of these antibiotics have been worked out, and many seem to be of peptide nature.2,17-19 Where studied, the extreme frequency of such strains, their antibacterial spectra, their activity in the presence of body fluids, and the rapidity with which fluctuation in concentration of such strains can occur have all argued for their potential significance. In addition, in Shigella infections20-22 and in diphtheria infections23 evidence has been obtained which indicates a flourishing of antibiotic producers in the local tissues during recovery from these infections.
As an experimental approach
HALBERT SP, KAZAR CS, SWICK LS. Mixed Bacterial Infections in Relation to Antibiotic ActivitiesIII. Staphylococcal-Diphtheria Infections of Guinea Pigs. AMA Arch Ophthalmol. 1957;57(5):716-723. doi:10.1001/archopht.1957.00930050728012