Callie Effler, a student at Lee University, worked in the lab of Dr. Eric Harvill. <\/p>\n\n\n\n
Abstract: Intracellular\nsurvival is a common trait among human pathogenic bacteria that has advantages\nfor the bacteria\u2019s protection from the host immune response, persistence, and\ndissemination within the host. Bordetella pertussis<\/em>, the gram-negative\nbacteria that causes whooping cough in humans, is commonly regarded as an\nextracellular pathogen. However, it has been recovered from macrophages in in\nvitro <\/em>experiments, and reported anecdotally in clinical samples. It is\nunknown what contribution to pathogenicity the intracellular population has, if\nany, on the host. In this work, our broad objective was to evaluate the impact\nof B. pertussis\u2019 <\/em>intracellular survival and its role in pathogenicity.\nTo do so, we planned to identify mutants similar to the wild type in general\nmeasured aspects of virulence, but that failed to survive inside of\nmacrophages. A transposon library of B. pertussis <\/em>UT25 was screened, resulting\nin the identification of several putative mutants that were deficient in\nintracellular survival. These strains were further screened for intracellular\ndeficiency as a confirmatory measure, and went through further in vitro<\/em> assays\nscreening for cytotoxicity, hemolytic activity, resistance to serum\ncomplementation, and general fitness (growth). Based upon these assays, mutant\nstrain G4 was the best candidate among those tested for an\nintracellularly-deficient mutant with similar virulence-related characteristics\nto the wild type. Preliminary C57 mouse infection studies suggest that the\nmutant strain behaves similarly to the wild type in vivo<\/em>, indicating\nthat intracellular survival may not be contributing to virulence. It is\nhypothesized that intracellular survival may be a phenotypic remnant of an\nancestral strain of B. pertussis that <\/em>transitioned from the environment\nto a become a human pathogen using this trait.<\/p>\n\n\nEffler<\/a>\n Callie Effler, a student at Lee University, worked in the lab of Dr. Eric Harvill. Abstract: Intracellular survival is a common trait among human pathogenic bacteria that has advantages for the bacteria\u2019s protection from the host immune response, persistence, and dissemination within the host. Bordetella pertussis, the gram-negative bacteria that causes whooping cough in humans,<\/p>\n