This study will test the safety and effectiveness of genetically altered T lymphocytes (white
blood cells of the immune system) in reducing viral load in patients infected with the human
immunodeficiency virus (HIV). The lymphocytes will have two genes inserted into them; a
laboratory-manufactured anti-HIV gene designed to inhibit HIV reproduction (either the RevTD
or Rev-TD-antiTAR gene), and a "marker" gene that will show whether or not the inserted genes
have gotten into the cells.
Identical twin pairs 18 years of age and older- one of whom is HIV-positive (infected with
the human immunodeficiency virus) and the other HIV-negative (not infected) may be eligible
for this study.
All participants will have a complete medical history and physical examination, blood tests
and a tetanus booster shot, if indicated. The non HIV-infected twin will then undergo
lymphapheresis to collect lymphocytes. In this procedure, whole blood is collected through a
needle placed in an arm vein. The blood circulates through a machine that separates it into
its components. The lymphocytes are then removed, and the red cells and plasma are returned
to the donor, either through the same needle or through a second needle placed in the other
arm.
The donor cells are grown in the laboratory for a few days, and then the new genes are
inserted into them. The genetically altered cells are grown in the laboratory for several
days until their numbers increase approximately a thousand-fold. They are then infused
intravenously (through a vein) into the infected twin. These procedures-lymphapheresis, gene
modification and infusion-will be repeated at approximately 2-month intervals up to four
times.
Each lymphocyte infusion takes about 60 minutes. The patient's vital signs (temperature,
pulse, blood pressure and breathing) are monitored frequently during the infusion and hourly
for 4 hours after the infusion. Blood samples are taken the day of the infusion, 3 days
later, and then weekly to monitor the gene-modified cells, immune status, viral activity, and
other factors. These tests may be done less often as the study progresses and more is learned
about the safety of the infusions. The infusions are done on an outpatient basis unless side
effects require that they be done in the hospital with post-infusion monitoring for at least
24 hours.
Patients will be followed for long-term effects of treatment monthly for the first 3 months,
once a month for the next 9 months and yearly from then on.
This study will contribute information about the use and side effects of gene therapy in HIV
infection that may lead to new treatment strategies. A potential direct benefit to
HIV-infected individuals participating in this study is reduced viral load; in laboratory
studies, the RevTD and Rev-TD-antiTAR genes have inhibited HIV spread in the test tube.
However, this is an early phase of study, and the likelihood of receiving this benefit is
unknown.