COLONIZATION AND CLEARANCE OF ENVIRONMENTAL MICROBIAL AGENTS UPON INTRANASAL EXPOSURE OF STRAIN C3H/HeJ MICE

Environmental dissemination of biotechnology agents is becoming a common practice. Most applications use historically innocuous species; however, potential health effects of individual products are not scrutinized unless they contain genetically engineered microorganisms. In order to investigate possible health concerns, four surrogate microbial agents were studied in vivo. Male C3H/ HeJ (endotoxin-resistant) mice were administered intranasally (i.n.) with ~107 Pseudomonas aureofaciens, Burkholderia cepacia, P. fluorescens, or P. putida. To determine clearance of the dosed bacterial strains, lungs, small intestine, large intestine, cecum, mesenteric lymph nodes ( MLN) , spleen, and liver were homogenized individually, plated, and dilutions inoculated onto selective media. Pseudomonas fluorescens and P. putida were eliminated from the lungs by 2 d posttreatment, and P. aureofaciens was not detected in the lungs by 5 d posttreatment. Burkholderia cepacia was reisolated from the lungs and cecum for the exper...