Alison Criss Laboratory Reveals How ‘Super Gonorrhea’ Resists the Human Immune System

July 27, 2018 by zrb8mf@virginia.edu

“UVA’s new research sheds important light on how the gonorrhea bacterium defeats the body’s antimicrobial defenses. Gonorrhea, the scientists determined, takes a two-fisted approach to neutralizing lysozyme, an enzyme that degrades bacteria and is abundant in tears, saliva and other secretions at body sites where the gonorrhea bacteria grows. Gonorrhea produces two proteins, known as inhibitors, that bind directly to lysozyme, preventing it from doing its job. Together, gonorrhea’s inhibitors “confer full resistance to this abundant antimicrobial defense,” the UVA researchers write in a new scientific paper.

When the researchers created a version of gonorrhea that lacked the two inhibitors, lysozyme killed the bacteria much more easily. Both of the inhibitors were found on the surface of the gonorrhea bacteria, making them able to be recognized by the immune system. That suggests that scientists could develop drugs or vaccines to make the bacteria susceptible to lysozyme, a major part of the body’s natural immune defense.

“It’s fascinating that the gonorrhea bacteria use two independent proteins to inhibit lysozyme, one of the main enzyme defenses our bodies have against bacteria,” said the study’s first author, Stephanie Ragland, a graduate student in the UVA biomedical sciences program. “Our finding suggests that lysozyme resistance is key to the survival of the gonorrhea bacterium. Going forward, we want to understand exactly how these lysozyme inhibitors work, and when and how the bacteria release them. This knowledge will help us develop new drugs or vaccines against gonorrhea, which are urgent priorities of the CDC and World Health Organization.””  source:  UVA Today