HIV
Researchers say they have discovered a new target on the HIV molecule that could potentially lead to a new class of anti-viral drugs to fight the virus that causes AIDS. "The greatest challenge in treating HIV today is drug resistance brought on when the virus mutates and renders existing drugs ineffective at stopping viral replication," said a lead researcher. "Our research has led to the identification of a new class of compounds that inhibit a novel target in HIV. These compounds disrupt the assembly of the HIV-1 capsid protein, which is a vital step in changing immature, non-infectious HIV into its mature, infectious form."
Scientists in California have provided the first detailed look at how human antibodies, proteins critical for the body's defense against invading pathogens, may actually drive human immunodeficiency virus (HIV) to mutate and escape detection by the immune system. The findings, reported online March 18 in the Proceedings of the National Academy of Sciences, may be key in efforts to develop an effective AIDS vaccine.
Researchers have discovered one way in which the human immunodeficiency virus (HIV) wins its cat-and-mouse game with the body's immune system. The study, published in the March 20, 2003, issue of the journal Nature, shows that HIV-1, a common strain of the virus that causes AIDS, uses a strategy not seen before in other viruses to escape attack by antibodies, one of the immune system's prime weapons against invading viruses and bacteria.
When exposed to high levels of human immunodeficiency virus (HIV), the cells lining the mouth can develop a low-level infection, a finding that increases our understanding of the risks of oral transmission of the disease. Researchers from Charles R. Drew University and the University of California, Los Angeles, report their findings in the March 2003 issue of the Journal of Virology. "The majority of HIV type 1 infections occur via mucosal contact, and there are several reports indicating that the oral mucosa may be one route of exposure," say the researchers. "It is difficult to confirm that oral mucosa is a major transmission portal because of the correlation between oral-genital contact and other transmission risk behaviors."
In a new study in mice, a modified form of an innocuous chimpanzee virus has shown marked potency as a protective vaccine against HIV, itself believed to have crossed into the human population from chimpanzees sometime in the 1930s. The study, led by researchers at The Wistar Institute, appears in the February issue of the Journal of Immunology. "Our results show this new vaccine is capable of inducing the kind of powerful immune response that we and others believe will be critical for controlling HIV infection," says Hildegund C.J. Ertl, M.D., professor and immunology program leader at The Wistar Institute, and senior author on the new study.
TMC114, a next-generation protease inhibitor, has demonstrated significant antiviral activity in multiple PI-experienced HIV patients currently failing PI therapy. In the 50 patient study, the median reduction in plasma viral load was -1.35 log10 copies/ml HIV-1 RNA after 14 days treatment with TMC114 boosted with low-dose ritonavir (TMC114/r); the maximum reduction was -2.49 log10. TMC114 is being developed by Tibotec, a Belgian pharmaceutical research and development company.
New research suggests that combining the chemotherapy drug paclitaxel with very low doses of the HIV-fighting drug AZT may shrink or even eradicate certain types of cancer tumors. Using both drugs in mice helped inhibit the enzyme telomerase, a component critical to the livelihood of some cancer cells. Telomerase helps to build and maintain telomeres ? protective strands of DNA at each end of a chromosome.
Inmates infected with HIV, the virus that causes AIDS, engaged in unprotected sex both before imprisonment and after their release at "exceedingly high rates," according to a new University of North Carolina at Chapel Hill School of Medicine study. Seventy-eight percent of N.C. men and women prisoners carrying the virus who had a main sex partner reported unprotected sex with that person in the year before they were locked up, the study showed. Twenty-six percent of them interviewed again soon after release admitted to already having sex without condoms with their main sex partners.
In a new study in mice, a modified form of an innocuous chimpanzee virus has shown marked potency as a protective vaccine against HIV, itself believed to have crossed into the human population from chimpanzees sometime in the 1930s. The study, led by researchers at The Wistar Institute, appears in the February issue of the Journal of Immunology. "Our results show this new vaccine is capable of inducing the kind of powerful immune response that we and others believe will be critical for controlling HIV infection," says Hildegund C.J. Ertl, M.D., professor and immunology program leader at The Wistar Institute, and senior author on the new study.
HIV patients who live in pain and use poor coping strategies to handle the stress of their illness also report that they have less energy and more limits on their physical, social and work activities, according to a new study. Patients who use self-distraction techniques or "give up trying to deal with" HIV-related stress feel less energetic, and those who use self-distraction or drugs or alcohol to cope say that their health limits their social activities, according to Mark Vosvick, Ph.D., of the University of North Texas and colleagues.
The National Institutes of Health is partnering research on new saliva tests offering multiple and rapid analysis of salivary secretions for use at home and in the dentist's office, calling for "more sensitive assays" useful in fighting terrorism or war. Oral fluids recently have shown "great diagnostic potential" in a variety of clinical situations, for detection of HIV and monitoring drug use (see the Spectrum Series report on saliva). But progress on this front hasn't always kept pace with expectations. Now, says the NIH, the technology is ripe and the time at hand for simultaneous multi-analyte detection of markers for disease and exposure to environmental, occupational or abusive substances including agents dispersed by bioterrorists.
Social support may play a small but potentially important role in helping HIV-positive people adhere to the complicated schedules for taking their drug "cocktails" to control the virus that causes AIDS. A pilot study of primarily indigent black and Puerto Rican men and women at an HIV clinic in New York City suggested that individuals who had the social support they needed were more likely to take their medications. The pilot project was part of a larger study to assess the efficacy of peer support to enhance people's adherence to their cocktail or Highly Active Antiretroviral Therapy.
Researchers have developed a new gene therapy approach that prevents the AIDS virus from entering human cells. The technique offers a potential way to treat HIV patients and could apply to any disease caused by a gene malfunction, including cancer. The research team created a new application for a genetic technology called small interfering RNA (siRNA). The synthetically designed siRNAs act as a catalyst to reduce the expression of specific genes and slow the progression of disease.
The social behavior of sex workers and transportation workers along the U.S. ? Mexico border has the potential to spread HIV and AIDS through North and Central America in much the same way the disease has spread through sub-Saharan Africa, according to a new University of Houston study. "The main thrust of the study focuses on the potential this social mechanism could play in the spread of AIDS as the virus gets into those populations of truck drivers," said the study's lead researcher. "Keep in mind that this is how the virus is believed to have spread throughout sub-Saharan Africa, as transportation workers moved through border regions."
A report of an individual infected with a second strain of HIV despite effective drug treatment following the first infection has researchers concerned. "For the first time, we've shown it is possible for an individual to become infected with two closely related strains of HIV," says Bruce D. Walker, M.D., a researcher at Massachusetts General Hospital and Harvard Medical School. The findings underscore the challenges vaccine developers face in creating a broadly effective vaccine against HIV. The first HIV vaccines may not prevent infection altogether, but rather may prevent HIV from causing disease by limiting the virus' ability to reproduce, explains Dr. Walker. This case shows that a hypothetical vaccine against one strain of HIV may not necessarily protect the vaccinee against other, closely related strains.
