Anatomy Question: Use your own words. A girl with a defective heart receives a new heart transplanted from another child who was killed in an accident. The patient is given an antilymphocyte serum containing antibodies against her lymphocytes. The transplanted heart is not rejected, but the patient dies of an overwhelming bacterial infection. Why was the antilymphocyte serum given? Why was the patient so vulnerable to infection? Solution Ans: antilymphocyte serum is given or suppress immune response to stop graft rejection as the heart received is not matched with receiver due to different HLA or MHC on the donor and recepient tissues. So that heart I.e allograft can\'t be rejected by host immune system. But here comes a problem I.e host immune system is compromised due to antilymphocyte serum,so no longer host immune system can fight against disease.so host is more prone to diseases and soon dies.