Since the graft came from Jack’s body, it was an autograft for him and therefore contained his own antigens that would not elicit an immune response. The skin was an allograft for Jill. Since the antigens in Jack’s skin were foreign, Jill would have mounted an immune response. The response would have been T-cell mediated and resulted in the destruction of the foreign cells. To avoid this outcome, Jill’s graft could have been prepared from her own skin. Alternatively, she could have been administered immunosuppressive drugs to minimize the immune response against the graft.