The Researchers Design The First Ever Vaccine For Chlamydia
Researchers have made progress toward the first ever vaccine for chlamydia, after revealing how a novel antigen reduced symptoms triggered by the bacterium Chlamydia trachomatis – the most common cause of the disease.
Chlamydia is one of the most common sexually transmitted infections and is usually transmitted through having vaginal, anal, or oral sex with an infected person. There are four species of bacteria that can cause infection – the most common of which is C. trachomatis.
Canadian researchers combined three individual proteins found in the bacterial species known to cause most cases of chlamydia, Chlamydia trachomatis, into one fused protein, BD584, in hopes that the new protein, or antigen, would trigger a sustained immune response to the germ when introduced to the body. They then gave laboratory mice BD584 via a nasal spray and infected them with a closely related species of C. trachomatis. Not only did the immunized mice clear the infection faster than mice not given the antigen, they also experienced symptoms like bacterial shedding from the vagina and fluid blockage of the fallopian tubes far less often.
Based on their results, they suggested BD584 is a promising candidate for a chlamydia vaccine. What is more, they also suggested that BD584 has the potential to protect against all strains of C. trachomatis, including those that cause trachoma – a type of eye infection.
If the BD584 antigen proves successful as a chlamydia vaccine, the researchers say it would be administered through the nose.
“Vaccine development efforts (for chlamydia) in the past three decades have been unproductive and there is no vaccine approved for use in humans,” said lead author Dr. David Bulir, a researcher at the M. G. DeGroote Institute for Infectious Disease Research at McMaster University, in a statement. “Vaccination would be the best way to way to prevent a chlamydia infection, and this study has identified important new antigens which could be used as part of a vaccine to prevent or eliminate the damaging reproductive consequences of untreated infections.”
Bulir and his colleagues hope their combination strategy might be able to provide protection against multiple strains, including those that cause trachoma, since the proteins used in the vaccine are essential to helping the bacteria infect and grow inside its host. The ease of delivering the drug to future patients is also another positive.
“This is easy and painless and does not require highly trained health professionals to administer, and that makes it an inexpensive solution for developing nations,” says study co-author Steven Liang, also of the Michael G. DeGroote Institute for Infectious Disease Research at McMaster.
The next step is more testing for effectiveness against different strains of Chlamydia and in different formulations.