Chaiken is a professor of biochemistry and molecular biology in the College of Medicine.
Jacobson is a professor of medicine in the Division of Infectious Diseases and HIV Medicine at Drexel University College of Medicine, specializing in infections diseases, internal medicine and HIV.
Welles is a professor in the School of Public Health, with research focuses on cancer, health disparities, HIV/AIDS, infectious diseases, sexually transmitted diseases and more.
Seeing a ‘Functional Cure’
Jeffrey Jacobson, chief of Drexel’s division of infectious diseases and HIV medicine, is developing a therapeutic vaccine to control HIV in already infected individuals. Since HIV mutates very readily to evade the body’s immune response, each individual has slightly different quasispecies, or strains, of HIV. Therefore, the vaccine would have to be personalized for the individual, according to Jacobson, who is the principal investigator.
To create the vaccine, a sample of the virus is taken from the infected individual’s own blood before HIV drugs are started. Investigators then take the RNA of the person’s virus, load it into the person’s own immune cells and give it back as a vaccine to try to stimulate a new, more potent response against HIV. The ultimate goal of the research, which is funded by the National Institutes of Health, is a “functional cure” of the infection—control of HIV without the need for any HIV medications.
Jacobson also has NIH funding to study a long-acting injectable anti-HIV antibody as an alternative treatment for HIV-infected patients who have demonstrated an inability to adhere to the rigors of taking daily oral anti-HIV medications.
A Warning About HAART
Drexel School of Public Health professor Seth Welles was a partner investigator on a new study that found that highly active antiretroviral therapy (HAART) is not as effective in suppressing HIV in certain HIV-infected individuals.
According to Welles and his fellow investigators, the implications of this research are extremely important, especially for HIV-infected men who have sex with men (MSM). The researchers point out that MSM may make sexual decisions based on their incorrect understanding that being on HAART and having undetectable blood viral load means they cannot transmit HIV. They may assume that HAART eliminates HIV in semen.
The study helped to explain the relationship between HAART, which reduces viral load, and risk factors for HIV. Other risk factors for HIV include STIs and genital inflammation, which enhance HIV replication in the genital tract and increase possible sexual transmission of HIV.
Based on their data, the researchers concluded that this higher prevalence of HIV in semen in MSM with undetectable levels of HIV in their blood is likely due to other STIs as well as genital inflammation. In other words, STIs and genital inflammation may lessen the effectiveness of HAART and transmission may still be possible.
Welles and his fellow investigators cautioned that more research needs to be conducted and made available both to HIV-infected MSM and their health care providers.
Stopping AIDS Before it Starts
Drexel College of Medicine professor Irwin Chaiken and his colleagues have found a class of compounds—peptide triazoles—that block the HIV virus-cell interaction. Some of these compounds also have the ability to “break” and thereby inactivate the virus before it encounters a host, while leaving the human cells undisturbed.
HIV infection is initiated by entry of the virus into a host cell, a process that depends on the fusion of the viral membrane with the membrane of the target cell. One very effective approach to preventing and potentially treating infection would be to inhibit this fusion.
This finding could lead to prevention and treatment options at the earliest stages of HIV-1 exposure. The peptide triazoles have the ability to inhibit the virus from multiple subtypes of HIV that are globally important. So far, they appear to work in all subtypes of the virus that have been tested.
Chaiken’s lab has collaborated in this research with Drexel engineers as well as a multi-institutional National Institutes of Health program project team.