Antigenic variation strategy of gonorrhea Antigenic Variation and Neisseria gonorrhea Gonorrhea is a leading cause of sexually transmitted disease. Neisseria gonorrhea can cause serious cervical and urethral infections that result in purulent discharge.
Gonorrhea is transmitted from person to person through direct contact, usually sexual.
The most remarkable feature of N. gonorrhea is its ability to evade the host's immune system through variation of its surface antigens, primarily the pili proteins. The mechanisms of antigenic variation for N. gonorrhea vary, and all occur at the DNA level. Likewise, phase shifting can occur in which repeated sequences in the pili genes are added or cleaved, changing the likelihood that the gene will be expressed. This small amount of variation sufficiently ensures that, as the host mounts an antibody response to the original pili protein, a new variation will go undetected and become the dominant form in the population. Because of the ability of N. gonorrhea to evade the hosts antibody response, vaccine development has been difficult.