To keep a patient healthy following an organ transplant, doctors must prescribe the right balance of immune-system-supressing drugs: The medications need to be strong enough to prevent rejection of the foreign body but not leave the immune system at risk for infection. Now, a study by Stanford scientists has pinpointed a little-known virus that spreads when these immunosuppressant drugs take effect. The anellovirus, first identified in 1997, could be a barometer of immune system strength, thereby informing more precise and less reactive treatment for transplant recipients.
Lead author Stephen Quake, PhD, and collaborators isolated specific DNA fragments floating in the blood plasma of 96 heart and lung transplant patients using a technique of genomics, of which Quake is a pioneer. The team studied how the drugs affected the body’s microbiome, or collection of bacteria, fungi and viruses.
As described in a release, the researchers found that “lower levels of anellovirus suggest a stronger immune system and an elevated risk of organ rejection, while higher levels of anellovirus suggest a weaker immune system with a corresponding shift in risk toward vulnerability to infection.”
Hannah Valentine, MD, professor of cardiovascular medicine and senior associate dean for diversity and leadership at the School of Medicine, remarked, “These findings suggest an effective tool to individualize the monitoring and, ultimately, the treatment of rejection. In the future, this could allow us to safely lower the doses of immunosuppressive drugs patients receive, thereby avoiding devastating side effects.”
Previously: Extracting signal from noise to combat organ rejection, Whole-genome fetal sequencing recognized as one of the year’s “10 Breakthrough Technologies” and New techniques to diagnose disease in a fetus