Expanding on previous research providing proof-of-principal that human stem cells can be genetically engineered into HIV-fighting cells, a team of UCLA researchers have now demonstrated that these cells can actually attack HIV-infected cells in a living organism. The study, published in the journal PLoS Pathogens, demonstrates for the first time that engineering stem cells to form immune cells that target HIV is effective in suppressing the virus in living tissues in an animal model, said lead investigator Scott G. Kitchen, an assistant professor of medicine in the division of hematology and oncology at the David Geffen School of Medicine at UCLA and a member of the UCLA AIDS Institute. "We believe that this study lays the groundwork for the potential use of this type of an approach in combating HIV infection in infected individuals, in hopes of eradicating the virus from the body, " he said.
For the first time, US scientists have shown that HIV-fighting cells engineered from human stem cells can suppress the virus in living human tissue in mice. The team, from UCLA in Los Angeles, California, had already shown in principle that it was possible to create cells that seek out and destroy HIV, but this is the first time they have shown this can be done in a living organism. Writing in the 12 April issue of the online open access journal PLoS Pathogens, the researchers suggest their findings show it may be possible to use human stem cells to create tailored cells that target and eradicate viruses like HIV, and thereby "engineer the human immune response to combat viral infections". However, there is still a lot of work to do before what happens in mice can be replicated in humans.
In this week's PLoS Medicine, Luis Montaner from the Wistar Institute, Philadelphia, USA and colleagues retrospectively apply a potential capacity-saving CD4 count model to a cohort of HIV-infected patients on antiretroviral therapy. The study's findings suggest that the model could be used to optimize laboratory capacity in settings where resources are limited. The authors stress that the method is not intended to replace CD4 count testing or establish a second tier of healthcare, rather the model is intended as a triage tool to prioritize laboratory capacity for patients who are a high priority. The authors state: "the implementation of our method could help focus laboratory-based CD4 count testing capacity on patients with higher likelihood of CD4 failure. This work provides the basis for future prospective testing of the model's overall safety, cost effectiveness and clinical outcomes in low-resource settings.
Researchers have gained important clues about immune system responses that could play a role in protecting people from HIV infection in follow-up studies from the world's largest HIV vaccine trial to date. Results from laboratory studies based on the trial were published in the New England Journal of Medicine. The HIV vaccine trial in Thailand, called RV144, showed that the group receiving the vaccine regimen was estimated to be 31.2 percent less likely to be infected than those who didn't get the vaccine, and researchers set out to learn why. Researchers analyzed samples from RV144 trial participants to look at immune responses in the vaccine recipients. The researchers found that different types of antibody responses were associated with a higher or lower rate of HIV infection. "By studying those who became infected compared to those who did not, we believe we have found very important clues for how the RV144 trial might have worked, " said Barton F.
Stanford University researchers have concluded that a once a day pill designed to prevent the spread of HIV could prove cost effective for high risk members of the population. The drug, known as tenofovir-emtricitabine, reduces the risk of HIV infection by nearly fifty percent in a 2010 clinical trial, and the test subjects who reported taking the pill religiously, had upwards of seventy percent reduction in HIVB infection. The pill, which is sold under the brand name Truvada, is also used for treating those already infected with HIV, but a landmark study in 2010 proved it effective for preventing the spread of the disease. The drug's maker, Foster City, Calif.-based Gilead Sciences Inc., has filed a supplemental new drug application to allow its use for prevention purposes. The scientists at Stanford were interested to see whether giving the pill to large tracts of the population would be cost effective.