In vivo growth of transplanted genetically altered intestinal stem cells.
OBJECTIVE
Intestinal stem cell transplantation is a potential method of delivering genes to the small intestine. The authors have previously demonstrated the survival of transfected intestinal stem cells implanted into the rat small intestine. This study examines the growth of genetically altered intestinal stem cells that were grown on a polycarbonate membrane and implanted into the rat small intestine.


METHODS
The IEC6 rat intestinal cell line serves as a model for intestinal stem cells. A subclone of the IEC6 cells was developed that stably expresses the lac Z gene introduced by a retroviral vector. The transfected cells were seeded at 500,000 cells/cm2 on a polycarbonate membrane. In 15 male Sprague-Dawley rats, a 0.75-cm enterotomy was created on the antimesenteric side of the small intestine 5 cm distal to the ligament of Treitz. A 0.5-cm2 segment of the membrane was sutured over the enterotomy with the cells facing away from the intestinal lumen. A segment of the omentum was wrapped around the patched enterotomy and sutured to the serosa. Three and 7 days after implantation, the implanted cells were retrieved, then fixed and stained with an X-gal solution. The number of cells was determined from the intensity of the X-gal staining. In five of the rats, frozen sections of the enterotomy sites were examined after staining with X-gal.


RESULTS
All 15 rats survived the implantation procedure. Initially, 0.32 +/- 0.11 million cells were implanted. At both 3 and 7 days, the enterotomy site still contained viable transfected cells. The number of viable cells increased substantially to 1.52 +/- 0.46 and 3.52 +/- 1.87 million cells at 3 and seven days, respectively (P < .05).


CONCLUSIONS
The polycarbonate membrane served as a good vehicle to efficiently deliver genetically altered intestinal stem cells to the small intestine. The transplanted cells continued to grow and stably expressed the gene product. This ex vivo approach to gene therapy has considerable therapeutic potential.
Kawaguchi
A L
AL
Division of Pediatric Surgery, UCLA School of Medicine, Los Angeles, CA, USA.
Dunn
J C
JC
Fonkalsrud
E W
EW
D000818:Animals; D002460:Cell Line; D017690:Cell Transplantation; D015316:Genetic Therapy / Q000379:methods*; D007413:Intestinal Mucosa / Q000166:cytology*; D007421:Intestine, Small / Q000166:cytology; D008297:Male; D008567:Membranes, Artificial; D011076:Polycarboxylate Cement; D051381:Rats; D017207:Rats, Sprague-Dawley; D012778:Short Bowel Syndrome / Q000628:therapy; D033581:Stem Cell Transplantation; D014162:Transfection
D008567:Membranes, Artificial; D011076:Polycarboxylate Cement; C005506:polycarbonate