Immunosuppressant drugs used to prevent rejection of transplanted organs may combat the HIV reservoir. Publishing their findings in the American Journal of Transplantation, researchers studied how the transplant drug sirolimus (rapamycin) affected the disease state of 91 HIV-positive transplantees, whom they followed for a median 3.2 years.

The researchers examined blood samples taken from the study participants—most of whom were on antiretroviral therapy—a respective 12, 26, 52 and 104 weeks following their transplants.  

The investigators found that those who took sirolimus had lower levels of HIV DNA. They theorized that the drug may reverse the latency of cells harboring HIV, causing the cells to produce HIV and possibly leading to an ultimate drop in the HIV DNA levels.  (Antiretrovirals cannot attack HIV that is in a latent cell.  But once the cell is activated ARVs can protect uninfected cells from the virus that the awakened cell produces, and researchers hope the virus will ultimately kill that cell.)

“Our study highlights the potential synergies that can occur when two very different disciplines merge their talents and resources,” lead author Steven Deeks, MD, of the University of California, San Francisco, said in a release.

Deeks theorizes that sirolimus may have other HIV-fighting benefits: including making immune cells less susceptible to infection by reducing the expression of the CCR5 coreceptors onto which the virus attaches before infecting the cells; and by increasing other immune responses that target the virus.

To read the abstract, click here.

To read the press release, click here.