UNDERSTANDING BLADDER REGENERATION tion with bladder matrix and bladder epithelium. Since immature smooth muscle cells and myofibroblasts are similar at 1 point yet eventually different, future efforts to direct these cells toward more normal development would have important implications not only in patients with abnormal bladders, but also i n those with abnormal wound healing or proliferative disease. CONCLUSIONS
Mature bladder smooth muscle cells undergo dedifferentiation, migration a n d redifferentiation to repopulate an acellular matrix graft. It is unlikely that adult fibroblasts from the surrounding tissue a r e induced by epithelium and matrix to form smooth muscle. The contractile behavior of bladder substitute materials likely reflects t h e properties of the host bladder.
Dr. Joseph Goodman performed t h e electron microscopic analysis of native and grafted bladder tissue, and anticytokeratin antibodies to cytokeratins 7, 8 a n d 14 were provided by Dr. E. B. Lane, University of Dundee. REFERENCES
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DISCUSSION
Dr. Anthony A. Atala. Have you analyzed growth factor biology in these matrices? Dr. Hsi-Yang Wu. No, we have not analyzed the matrix for growth factors.