The Use of Antibiotics in the Preparation of Amphibian Cell Cultures from Highly Contaminated Material

Abstract

Embryos and larvae of Xenopus laevis are contaminated with a wide range of micro-organisms from the maternal cloaca. Primary monolayer cultures prepared from them were usually destroyed by endogenous contaminants. Fungal contamination was readily eliminated by the usual procedures. The high incidence of bacterial contamination was not reduced by penicillin, streptomycin, tetracycline or combinations of the three. Contamination by Gram-negative bacilli, especially Proteus and Pseudomonas, remained. Treatment with carbenicillin, gentamicin or the combination of polymyxin E with kanamycin usually eliminated all infection. The cytotoxicity of effective antibiotics was tested. The basic requirements of a method for eliminating endogenous bacterial contamination and the relative merits of the three effective treatments are discussed.