Over the past two decades, there has been a change in the causes of bulbar urethral stricture (BUS), and fall astride injuries have become the most common cause, followed by iatrogenic trauma and gonococcal urethritis.(1) Traditional treatments like urethrotomy and dilation for short strictures (<2cm) have high recurrence rates, thus negatively impacting the quality of life.(2,3) To address this, novel treatments like tissue-engineered cell therapy using autologous adult live cultured buccal epithelial cells (AALBEC) have emerged. Uregrow®, developed by Regrow Biosciences in India, offers a minimally invasive, endoscopic approach with reduced morbidity. This innovation holds promise for addressing structural and functional challenges in short-length strictures more effectively.
Procedure: Step 1- Buccal mucosal biopsy
Approximately 1×1.5 cm of oral buccal mucosa tissue was collected from the patient’s inner cheek under local anaesthesia. The tissue was then placed in DMEM culture using sterile techniques and sent to a GMP-certified laboratory.
Step 2- Epithelial cells Isolation and Culture
AALBEC were isolated through enzymatic digestion of buccal mucosa tissue, followed by the separation of the epithelial layer from the submucosal tissue. The cells were then cultured, expanded ex vivo, tested, and formulated as a suspension containing not less than 2.5 million cells per 0.4 mL of DMEM culture per vial (Figure 1). The product remains stable for 72 hours when stored at 2–8°C.
Step 3- Endoscopic Implantation (Figure 2)
Bulbar urethral strictures are treated using cystourethroscopy under spinal anesthesia, followed by dorsal visual internal urethrotomy (DVIU) at the stricture site and a 12Fr Foley was placed and pulled towards bladder neck. Cultured cells mixed with a fibrin-based scaffold are applied to the urethrotomy site via a ureteroscope (8.6Fr). The scaffold solidifies at body temperature, securing the cells. A Foley catheter was left in situ for two weeks. Follow-up evaluations occur at 8, 12, and 24 weeks post-procedure to monitor outcomes and ensure success.
Outcomes
Surya P. Vaddi reported positive results with a thermoreversible gelation polymer scaffold, while a phase 2b trial by Sanjay B. Kulkarni demonstrated the safety and efficacy of AALBEC, improving AUA symptom scores and uroflowmetry at 24 weeks.(4,5) Our study involving 30 patients further confirmed significant improvements in AUA scores, maximum flow rates, voided volumes, and reduced post-void residual volumes over a 24-week period, highlighting the effectiveness of this approach.
Figure 1: (A) Suspension containing cells in DMEM medium. (B) Armamentarium required for the procedure: Cystoscope, Guidewire (0.032-0.038 inch), Sachse’s optical urethrotome, 5Fr Ureteric catheter, 8.6Fr Ureteroscope, 12-14Fr Foley catheter.
By Dr Umesh Sharma, ABVIMS & RML Hospital, New Delhi
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