Which of the following statements correctly characterize the role of histocompatibility typing in transplantation?

C. Histocompatibility typing may involve serologic, cellular, and molecular procedures for typing.

D. The role of histocompatibility matching in transplantation is controversial.

E. The cross-match test is carried out to determine whether a potential graft recipient has antibodies against the donor.

DISCUSSION: The concept of histocompatibility and the rules governing the susceptibility to rejection were deduced early in this century by such investigators as Jensen, Little, and Tyzzer, who were interested in the inherited resistance or susceptibility to transplanted tumors. The application of histocompatibility to clinical transplantation, however, had to await the advent of immunosuppressive therapy. Despite the practice of organ transplantation for more than 30 years, the role of histocompatibility typing in transplantation is controversial. Although grafts between HLA-matched donors and recipients exhibit better survival than HLA-mismatched grafts, matching is not routinely performed before transplantation of the heart or liver, and the outcome of these grafts may be very good. Histocompatibility typing involves the use of a variety of techniques—serologic, cellular, and molecular—to identify the antigens carried by the donor and the recipient. In addition to formal typing, the recipient is tested via cross-match for antibodies against the donor.