In the last month, UCLA researchers have published two studies that contribute to the search for both the prevention and treatment of AIDS.
A group of researchers from the UCLA AIDS Institute and the Los Alamos National Laboratory published a study exploring why some mothers with HIV-1 transfer the virus to their babies through the uterus while others do not, leading them closer to finding a vaccine for HIV.
Meanwhile, researchers from the AIDS Institute and the Institute for Stem Cell Biology and Medicine showed for the first time that human embryonic stem cells can be formed into human T-cells, giving momentum to a gene therapy approach to fighting AIDS.
AIDS is caused by the damage of the immune system by the human immunodeficiency virus (HIV) and has killed 25 million people worldwide since the virus was first recognized in the early 1980s, according to the Joint United Nations Programme on AIDS.
Though treatment can slow the effects of the virus, there is currently no cure.
As a part of the 10-year study examining virus transfer between mothers and babies, UCLA researchers studied 38 randomly selected infant-mother pairs and found that mothers who had the maternal autologous neutralizing antibody (aNAB) were significantly less likely to transmit HIV-1 to their babies.
Antibodies are large, Y-shaped proteins used by the immune system to identify and neutralize foreign objects like bacteria and viruses. Researchers determined that a mother who has aNAB transfers the antibody through the placenta into the fetal bloodstream and therefore to the fetus, naturally vaccinating the child against HIV-1.
“This is the first study that shows that antibody is important in transmission from mother to child, and it also shows that if HIV-1 is transmitted, the strain of the virus transmitted to the infant is the same strain that was resistant to antibody in the mother,” said Dr. Yvonne Bryson, chief of pediatric infectious diseases at the Mattel Children’s Hospital at UCLA and an author of the study.
The study’s results suggest that the antibody has a selective or protective effect on HIV-1 transmission.
“I think it is an important discovery because a neutralizing antibody is important for the future of a vaccine against HIV,” said Bryson.
Researchers around the world have worked for decades to find a vaccine for AIDS, believing it is the only option that can ultimately end the epidemic.
“The vaccine could be used on infants, young adolescents, anyone who is at risk. This technology could potentially stop the epidemic,” said Bryson.
The second group of UCLA researchers approached the AIDS problem from a different angle, working to develop a system of cell replacement and gene therapy that could counter the disease in case an effective vaccine ultimately proves unattainable.
UCLA researchers coaxed human embryonic stem cells into T-cells, which regulate immune response and are the main target of the HIV virus.
“Human embryonic stem cells are obtained from the cells of an early-stage human embryo and mature to make all the organisms and tissues of the human body,” said Dr. Jerome Zack, professor of medicine and of microbiology, immunology and molecular genetics at the David Geffen School of Medicine at UCLA and author of the study.
Researchers developed blood stem cells from human embryonic stem cells in petri dishes and then injected the blood cells into a human thymus they had implanted in a mouse.
The thymus, an organ located above the heart, where T-cells traditionally develop, turned the human blood cells into human T-cells.
“People have worked with mouse embryonic stem cells for 20 to 30 years, but using human embryonic stem cells is completely new,” said Zoran Galic, professor in the department of medicine, division of hematology and oncology and lead researcher on the study.
“The ability to get human embryonic stem cells to form T-cells is a holy grail in our field. This challenge had to be surmounted before we could move forward in treating HIV,” said Zack.
Researchers say the study is not important as an immediate promise of an HIV treatment, but because it shows for the first time that this technology is even possible.
Though both studies are years away from providing tangible treatment to patients suffering from HIV, researchers believe they are absolutely integral to the advancement of the fight against AIDS.