DNA amplification determines donor-cell fate in cryopreserved skin allografts

Cryopreserved donor skin-cell survival was tested after allo- and isotransplantation by DNA amplification of male donor-cell genes which detects trace quantities of cells. Essentially, all cryopreserved allograft skin cells were rejected at the recipient site. Fine-haired, cryopreserved, belly skin of male BALB/c mice was transplanted onto the coarser-haired back of either female Swiss-Webster mice (allograft) or female BALB/c mice (isograft). Six weeks later, skin samples from the graft sites were tested by DNA polymerase chain reaction (PCR) amplification. Although allografts initially engrafted, more than 99.9 percent of male allograft skin cells were subsequently rejected, and gradually replaced by hairless host scar tissue. Clinically, all isografts, including hair follicles, engrafted permanently and maintained donor-cell SRY gene sequences in fine-haired graft site cells. Thus, cryopreservation maintained both the viability and antigenicity of mouse skin cells, because allografts were rejected and isografts survived. Furthermore, DNA amplification, quantified at multiple control dilutions and amplification cycles, can conclusively determine the fate of transplanted cells.