AIDS Virus in Semen Distinctly Different than in Blood
Researchers have discovered distinct differences between the AIDS virus in semen, compared to blood. Scientists say the AIDS virus might undergo changes in the genital tract that are important to understand for preventing the spread of HIV. Rather than looking at HIV in the blood, the scientists suggest it might be more important to look at the behavior of the AIDS virus in semen.
“If everything we know about HIV is based on the virus that is in the blood, when in fact the virus in the semen can evolve to be different, it may be that we have an incomplete view of what is going on in the transmission of the virus,” said senior study author Ronald Swanstrom, PhD, professor of biochemistry and biophysics and of microbiology and immunology at the UNC School of Medicine." Researchers used genome sequencing to find the difference between the AIDS virus and semen and blood.
Targeting AIDS Virus in Semen Could Stop Transmission
Swanstrom says, “When we looked at sequences in the blood, we hardly found any that were the same, it was a very complex and diverse population. But when we looked in the semen, suddenly we were getting the same sequence over and over again.”
There were distinct differences between HIV in semen, compared to the AIDS virus in blood, that had to do with surface gene coding- called envelope or Env - that contain information for HIV replication. The difference between the virus in semen and blood could be significant because the researchers found HIV replication takes much longer to occur in semen versus blood. It takes longer for T cells to replicate in the seminal tract, while several of the viruses rapidly expanded over a short period of time. Compared to blood, the AIDS virus in semen was found to be fairly homogenous, found when the researchers analyzed cytokines and chemokines that keep HIV activated.
The researchers are now exploring exactly what's really happening in semen that's different than in blood, in hopes of unraveling how HIV is transmitted. Understanding the nature of the AIDS virus in semen could lead to the ultimate goal of stopping the transmission of HIV altogether.