Isolation and culture of airway epithelial cells from chronically infectedhuman lungs

We describe procedures for isolating and culturing airway epithelial cells from chronically infected human lungs. Experience in our Laboratory demonst rated the need to balance pathogen eradication against antibiotic toxicity to epithelial cells. To provide a logical basis for antibiotic selection an d dose, we systematically analyzed the cytotoxicity of antibiotics useful a gainst typical pathogens. Alone, colistin, ciprofloxacin, doxycycline, and tobramycin were moderately toxic at concentrations close to those used in c ell culture, whereas amphotericin, ceftazidime, chloramphenicol, imipenem, meropenem, piperacillin. sulfamethoxazole/trimethoprim, and vancomycin were nontoxic even at concentrations many times the antimicrobial level. Epithe lial cytotoxicity of combined antibiotics was additive, with no evidence of competition or synergism. Antibiotics had little effect on initial cell at tachment and did not acutely lyse cells, but inhibited subsequent growth. I nterestingly, cytotoxicity decreased markedly with increasing epithelial ce ll density. Cystic fibrosis (CF) and non-CF epithelial cells showed no diff erences in sensitivity to the antibiotics tested and initial exposure to an tibiotics did not affect the electrophysiologic properties of resistance or short circuit current in well-differentiated cells. Tailored combinations of antibiotics at appropriate doses killed even multidrug-resistant bacteri a. Thus, epithelial cells can Usually be cultured from chronically infected CF airways.