| Authors |
Prakapaitė, Rūta ; Semoškaitė, Rasa ; Banevičienė, Rasa ; Saab, Frederic ; Šliumbaitė, Zita ; Plančiūnienė, Rita ; Kavaliauskas, Povilas |
| Abstract [eng] |
Introduction: Uropathogenic E. coli (UPEC) is considered exceptionally responsible for the significant rates of urinary tract infections and neonatal meningitis. Generally, virulence factors define capability of UPEC to attach to mucosal and urothelial tissue of a host, escape evasion of host defense mechanisms, colonize kidneys and cause disseminated systemic infections. A live host is needed to recapitulate the complex structure of tissues for studying the virulence of pathogens, whereas in vitro models are constrained. However, experiments on live hosts are limited because of ethical reasons. The aim was to develop an ex vivo porcine kidney model for studying growth and virulence of UPEC and to investigate the interaction between bacteria and renal tissue. Materials and methods: Explants (±0,5 cm3) were harvested from fresh porcine kidneys and treated with PBS, supplemented with streptomycin/penicillin G. Afterwards PBS washed renal explants were incubated in RPMI-1640 medium, supplemented with 10% FBS and ampicillin. The viability of explants was assessed by using Alamar Blue assay. Explants were challenged to 8,5 x 105 CFU/mL of different UPEC strains (n=9) with diverse serotypes and profiles of virulence genes (fimH, cnv, iss, ibeA, neuC). To quantify the number of adhered bacteria, explants were pretreated with Cytochalasin D prior to infection. To quantify the amount of tissue associated and internalized bacteria, Cytochalasin D was omitted. Results: Renal explants retained their viability after 16 hours of incubation. After incubation, 1,34 x 1010 CFU/g of clinical isolate E1 (O:15, fimH, cnv, iss) were adhered, but not internalized to the explant, whereas E6 (O:15, fimH, ibeA) 1,29 x 1010CFU/g associated and 9,45 x 109CFU/g internalized via other than actin F dependent pathway to the explant. Conclusion: The successfully developed renal model was shown to be an effective approach to study virulence of UPEC[...]. |
