Donor-Derived Viral Specific T-cells (VSTs)

The stem cell matched donor will be asked to provide a blood donation for the VSTs generation. In the laboratory, the investigators will treat this blood sample to select out the cells that will help fight viruses. The cells will be grown with peptides (protein fragments that represent parts of the virus that will encourage the donor immune cells to grow). The cells will be grown in the laboratory so that there is a stock of virus fighting cells for the patient to use in the future. The investigators will freeze the cells and store them in a freezer in the laboratory. If the patient has signs of virus in their blood after the transplant, they will be given the cells to help fight the infection. If there are signs that the cells are helping fight the infection, more cells may be given. The patient may get the cells up to 5 times, with 21 days between each treatment (this timeframe may be shortened to 14 days for patients with no evidence of viral response). If the patient does not show signs of a virus, the cells will stay in the freezer. Following VST infusion, (s)he will be monitored with physical exams daily while inpatient and weekly while outpatient as well as blood tests weekly until 30 days after the last infusion of cells. The patient will have 3 teaspoons (15 mL) of blood drawn and urine collected before each cell infusion and then once a week after each infusion for 4 weeks and then once a month if possible for 1 year after the last infusion, all to monitor for the viral response.