Sustained ability for fibroblast outgrowth from stored neonatal foreskin: a model for studying mechanisms of fibroblast outgrowth

Fibroblast cultures derived from neonatal foreskin explants have been an important model for understanding the basic mechanisms of fibroblast function and activity. Neonatal foreskin has been routinely used for establishing such fibroblast cultures in vitro. In general, tissue explants and fibroblast cultures are established from freshly harvested neonatal foreskin tissue. It is unknown whether prolonged storage of tissue, even in optimal growth media and conditions would still result in successful explant outgrowth. Specifically, no studies have properly examined the maximal duration of foreskin storage that can produce viable fibroblasts with normal growth and synthetic characteristics. We, therefore, set out to isolate and propagate fibroblast cultures from neonatal foreskin tissue that had been kept in complete culture media at 4°C for various periods of time. We found that outgrowth and propagation of viable fibroblasts in vitro occurred with foreskin samples obtained within 24 days after surgical harvesting. The morphology, cellular proliferative capacity (measured by [3H]-thymidine uptake), steady state levels of α1(I) procollagen mRNA, and collagenous protein synthesis were comparable among fibroblast cultures derived from foreskin explants established 3 days (control) and up to 24 days (but not 38 days) after tissue harvesting. These studies demonstrate that viable and functional fibroblasts, with apparently similar in vitro characteristics, can be isolated and propagated from explants of neonatal foreskin tissue that have undergone prolonged storage. Moreover, these findings may be useful in understanding the lack of fibroblast growth in such conditions as found in delayed wound healing and aging.