1.Urethral reconstruction using oral keratinocytes-seeded bladder acellular matrix graft
Chao LI ; Yuemin XU ; Lujie ONG ; Qiang FU ; Lei CUI ; Shuo YIN
Chinese Journal of Urology 2008;29(6):368-372
Objective To investigate the feasibility of replacing urinary epithelial cells with oral keratinocytes by being seeded on bladder acellular matrix graft(BAMG). Methods Twenty-four male rabbits were randomly divided into 2 groups:experimental group and control group.A length of 2.0 cm and width of 0.8 cm penile urethral mucosal defect was induced in the anterior urethra 2.0 cm awav from the urinary meatus in all the rabbits.Oral keratinocytes were isolated from a small buecal mucosa(1.0 cm×0.4 cm)of the 12 rabbits in experimental group and seeded onto a culture dish with a feeder layer of 3T3 mouse fibroblasts inhibited by mitomycin(i3T3).Passage 2 oraI keratinocytes cuItured with i3T3 were expanded and seeded onto sterilized BAMG(2.2 cm×1.0 cm)to repair the de-fects of the urethra.Urethroplasty was performed with BAMG with no cell seeding in the controlgroup.Catheter examination and retrograde urethI ography was done in 1,2 and 6 months after graft-ing.The urethral grafts were harvested and analyzed by histological staining. Results Oral kerati-nocytes seeded onto a feeder layer of i3T3 had better morphous and amplification capability.The corn-patibility of the compound graft was assessed by HE staining and scanning electron microscope.Twelve rabbits in the experimental group could void without difficulty.Catheter examination and ret-rograde urethrogram revealed that a wide urethral caliber was maintained with no sign of strictures and fistula formation.Histological examination showed the grafted urethra was covered with smooth mu- cosa with no strictures at 1,2 and 6 months.The oral keratinocytes of the graft still existed even 6 months after grafting.On contrast,gross and urethrogram demonstrated urethral stricture in the con-trol group.And inflammatory reactions could be found in the area of the stricture through light micro-scope. Conclusions Oral keratinocytes have good compatibility with BAMG and the compound graft could be used for urethral reconstruction in the animal model.