16.0 PARENT'S/PATIENT'S SUMMARY STATEMENT 
ADMINISTRATION OF NEOMYCIN RESISTANCE GENE MARKED EBV 
SPECIFIC CYTOTOXIC T LYMPHOCYTES TO RECIPIENTS OF MISMATCHED- 
RELATED OR PHENOTYPICALLY SIMILAR UNRELATED DONOR MARROW 
GRAFTS FOR LEUKEMIA 
You have/your child has a type of blood cell cancer that is very hard to cure with standard 
treatments and you/your child will receive a bone marrow transplant. Because you/your 
child does not have a brother or sister whose marrow is a "perfect match", this bone marrow 
will come from a donor whose marrow is the best match available. This may be a close 
relative or an unrelated person whose bone marrow best "matches" yours/your child's, and 
who agrees to donate marrow. As this marrow will not be as closely matched as a brother 
or sister who is a "perfect match" there is a higher risk of problems. One of these problems 
is that because the new immune system may be slow to grow back you/your child will be 
at risk of serious or fatal viral infections. 
EPSTEIN-BARR VIRUS (EBV) INFECTION 
One virus that can cause problems after this type of transplant is Epstein Barr virus (EBV). 
In normal people, this virus causes a flu like illness (sometimes called infectious 
mononucleosis or glandular fever or kissing disease) and usually gets better when the 
immune system controls the infection. However the virus remains hidden in the body for 
life. After a transplant, while the new immune system is growing back, the EB virus can 
come out and infect cells and cause them to grow in an uncontrolled manner. Patients can 
develop fevers, swollen lymph nodes and damage to other organs such as kidneys and lungs. 
This infection acts like a cancer because the cells infected with EB virus grow very quickly 
and there is no known effective treatment. This sort of infection will occur in between 10- 
30% of patients receiving a transplant from a donor who is not a perfect match and is fatal 
in nearly all these cases. 
This infection occurs because the immune system cannot control the growth of the cells. We 
want to see if we can prevent it from happening by giving you/your child special T cells that 
we have grown from your/your child's marrow donor. These cells have been trained to 
attack EB virus infected cells. We will grow these T cells from blood taken from your/your 
child's donor at the time of bone marrow harvest. These T cells will be stimulated with the 
donor's EB virus-infected cells which have been treated with radiation so they cannot grow. 
After mixing these cells together we will be able to grow special T cells from the donor that 
can attack EBV infected cells. We will then collect the T cells and make sure they can kill 
the virus infected cells. 
MARKING OF T CELLS 
To learn how long these T cells last when we have given them, we will mark them with a 
special bacterial marker gene. We will use a mouse virus that has been changed to keep it 
from causing infection. Tne marker, a gene called Neo R is put inside this special virus. 
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