Roanoke Times
                 Copyright (c) 1995, Landmark Communications, Inc.

DATE: SUNDAY, September 17, 1995                   TAG: 9509180080
SECTION: NATIONAL/INTERNATIONAL                    PAGE: A-15   EDITION: METRO 
SOURCE: Associated Press
DATELINE: WASHINGTON                                LENGTH: Medium

ORGAN REJECTION FACTOR IDENTIFIED

Dr. Victor H. Engelhard of the University of Virginia said Thursday he and his colleagues have identified a compound that originates from the male Y chromosome and causes an immune reaction from female tissue.

Engelhard said the compound, a group of amino acids linked together to form a peptide, are recognized as foreign and are attacked by immune system cells in females. The compound causes formation of what is called the H-Y antigen.

The researcher said the antigen starts a reaction that can lead to the rejection of hearts, lungs and kidneys transplanted from males to females. This rejection was first recognized in 1955, but its origin has puzzled doctors because males do not have a similar rejection reaction to transplanted female tissue.

Engelhard said there are drugs now that control rejection of transplanted solid organs. But transplantations of bone marrow, which include immune system cells, from females to males cannot be treated with such drugs and the rejection can cause a serious illness, he said.

Bone marrow transplantation is used most often in the treatment of leukemia. Engelhard said doctors often avoid using female bone marrow in males because of the reaction.

``It can cause what is known as graft-versus-host disease in which the transplanted bone marrow attacks the body of the recipient,'' he said. ``This can be quite serious.''

Now that the source of the antigen has been identified, Engelhard said it may be possible to develop drugs that overcome the problem.

A report on the study was published Friday in the journal Science.