Somewhere between 10% and 25% of the population in developed countries are believed to be carriers of simplex virus type 2 (HSV-2), which causes genital herpes, one of the most common sexually transmitted diseases.
Genital herpes is incurable and no vaccine has been discovered despite extensive research. The infection also promotes transmission of HIV. As a result, development of a vaccine is a high priority. Establishing genital immunity has proven difficult.
As part of her doctoral thesis at Sahlgrenska Academy, Josefine Persson has conducted experiments to explore two options for establishing immunity to genital herpes: injecting a vaccine into the skin or give it through the nasal mucosa.
“The studies show that both methods provide effective immunity to acute genital infection and that the nasal vaccination also offers partial immunity to establishment of latent infection,” Dr Persson says. “Protection against transfer from the genital mucosa to the nervous system is highly significant because the virus remains latent in the nerve cells for life, which may cause recurring problems and means that it can be transmitted to others.”
A vaccine that is based on only part of a bacteria or virus must include an adjuvant that activates the immune system and/or improves uptake. Dr Persson tested two different adjuvants that elicited immunity to genital herpes infection in animals when combined with viral proteins.
“Both adjuvants have previously been tested in human trials, so they could be included in a vaccine,” she says.
Women are more susceptible to genital herpes than men. The thesis also evaluated immune responses after an experimental vaccine was applied locally to the vaginal mucosa. The findings can be used in future studies concerning vaginal immunity.
“My hope is that the results of the thesis can facilitate development of a vaccine against genital herpes,” Dr Persson says.
Dr Persson defended Immunization approaches and molecular signatures for mucosal immunity to primary and recurrent genital herpes on June 11.
Link to thesis: https://gupea.ub.gu.se/handle/2077/38383
FACTS ABOUT GENITAL HERPES
More than 500 million individuals are carriers of herpes simplex virus type 2 (HSV-2). The virus infects the genital mucosa and subsequently remains latent in the nervous system. Symptoms include painful blisters and sores in the genital tract, and may cause infections in the brain and nervous system.
During latent infection the virus can be reactivated and cause recurring problems. Transmission from mother to infant during childbirth can also lead to serious illness. Nevertheless, most people do not experience any symptoms.
For additional information, feel free to contact:
Josefine Persson, Sahlgrenska Academy, University of Gothenburg
Supervisor: Ali M. Harandi, Docent, firstname.lastname@example.org
BY: Krister Svahn