Donor-Derived Humoral Immunity, Hematopoietic Stem Cell Transplantation, TAR

This research study is for subjects that are receiving a bone marrow transplant. As part of the transplant subjects will receive stem cells from a donor who has agreed to donate stem cells for them. Unfortunately, it takes a long time for the immune system to recover after a bone marrow transplant. This makes it more likely for patients to develop serious infections. This study is being done to better understand how the immune system will recover after transplant. The immune system includes the cells that help fight infection. This study will help investigators understand which patients are at risk for developing infections after transplant. All children and adults receive standard vaccines (shots) during their lifetime to provide protection from many different infections. One such infection is tetanus, a bacteria that can cause life-threatening problems. After transplant patients no longer have protection from infections such as tetanus. Therefore, most patients need to receive all their vaccine (shots) again after transplant. This is usually done 1-2 years after transplant, since it may take that long for patients to have a normal immune system. However, the investigators believe that the time it will take for the patient to develop normal protection against tetanus can be shortened if both the patient and the patient's stem cell donor receive a tetanus vaccine. The goal of this study is to determine if giving a tetanus vaccine to the donor and the patient will provide the patient with enough protection (immunity) to prevent infection following bone marrow transplant.