Researchers see hope for sex disease vaccine

Scientists said on Thursday that they are a step closer to a vaccine against a bacteria that causes one of the world’s leading causes of blindness and a common sexually transmitted disease. Research into the vaccine was stalled 25 years ago, but recent advances in DNA knowledge have led to a promising candidate for a vaccine against Chlamydia trachomatis, researchers Harlan Caldwell and Deborah Crane said in interviews on Thursday. The bacteria causes the sexually transmitted disease chlamydia, which can cause pelvic inflammatory disease and infertility in women. The bacteria can also cause trachoma, an infection of the eyes that can cause blindness.

Caldwell and microbiologist Crane reported in a study released this week that antibodies to one protein may prevent infection by all 15 strains of Chlamydia trachomatis. The study was released by the Rocky Mountain Laboratories of the National Institute of Allergy and Infectious Diseases.Research at the laboratory in Hamilton, Montana, has been conducted in test tubes, but will now move on to animal testing, the scientists said. Caldwell said animal testing could be complete within two to three years and clinical trials in people within five years. “When we find test tube results that are this encouraging, it gives us a lot of optimism in moving forward,” Caldwell said. “This is in the first step, there’s no question, but the fact you can kill chlamydia in a test tube, and not only kill it, but kill all the strains of the disease, it has great promise in moving forward.”

Caldwell first began work identifying the protein in 1975, but did not have adequate technology for the research. He froze the materials and did not resume work until a few years ago, when new information about the genetic makeup of the bacteria made more research possible. Trachoma is the world’s leading cause of preventable blindness, according to the World Health Organization, and more than 150 million people, mostly in developing countries, currently need treatment. There are 90 million cases of chlamydia worldwide and studies estimate four to five million new cases in the United States each year, according to the WHO, which calls chlamydia “an enormous public health problem throughout the world.” “If this does turn out to be protective against multiple variants of Chlamydia trachomatis, then this would be a very big thing in the world of chlamydia, because potentially we could protect young women from the different strains of chlamydia, and it could be used in the third world to prevent trachoma,” Crane said. “It could have a huge impact economically and to prevent STDs.”

February 14, 2006

Original web page at Reuters