AMHERST, Mass. – The University of Massachusetts Amherst has entered into an option agreement with BioVeris Corp. of Gaithersburg, Md., giving the company exclusive patent rights to a unique vaccine candidate for Chlamydia, the most frequently reported bacterial sexually transmitted disease in the United States. In a separate agreement, BioVeris will fund up to $600,000 of UMass Amherst research aimed at developing a vaccine candidate.
Each year there are approximately 90 million new cases of sexually transmitted Chlamydia worldwide. Even though this is an underreported disease, the U.S. sees 2.8 million new cases annually, resulting in an estimated healthcare cost of more than $2 billion. Two species of the bacteria are serious human pathogens and a third is a major cause of diseases in livestock and birds. Yet a vaccine that protects against all strains of Chlamydia has long eluded scientists, and many have shied away from working with the notorious and seemingly intractable bacteria.
Not so with UMass Amherst scientists Lloyd Semprevivo, veterinary and animal sciences; Elizabeth Stuart, microbiology, and Wilmore Webley, microbiology. Continuing work pioneered by Stuart and the late A. Bruce MacDonald in the early 1980s, these researchers have come far in isolating a vaccine target and are closing in on its structure.
Usually vaccines work by treating an individual with some form of the disease-causing organism—often a weakened or dead version, or just a relevant piece—that can trigger a protective immune response. The immune system of a treated individual then makes antibodies, proteins which bind to the pathogen and ultimately help destroy it. As part of the immune response, “memory cells” also form which usually remain available to mount a quick, effective response when the pathogen is encountered again.
A portion of the disease-causing organism that can stimulate the immune system, an antigen, can be an ideal candidate for a vaccine. But isolating and characterizing a broadly protective antigen has proved difficult with Chlamydia. Like a virus, the bacterium grows only inside a host cell, and the critical antigen is a strange chimera of carbohydrate and fat, not the usual protein. Nonetheless, Stuart and colleagues have persevered and are pleased about the partnership with BioVeris.
Once UMass Amherst scientists isolate the candidate antigen, BioVeris will chemically characterize it, and the process of assessing its potential as a human vaccine component will begin, say the researchers.