Gene Mutation Yields Attenuated Blastomyces Strain with Vaccine Potential.(Brief Article)

2001 JAN 31 - (NewsRx.com & NewsRx.net) -- Researchers in the United States report that by mutating the WI-1 gene in the fungus Blastomyces dermatitidis, they have created an attenuated strain that stimulates protective immunity.

"Systemic fungal infections are becoming more common and difficult to treat, and vaccine prevention is not available," wrote M. Wuthrich and colleagues, University of Wisconsin. "Pulmonary infection with the dimorphic fungus Blastomyces dermatitidis often progresses and requires treatment to prevent fatality."

Wuthrich et al. published their study in the Journal of Clinical Investigation ("Mutation of the WI-1 gene yields an attenuated Blastomyces dermatitidis strain that induces host resistance," J Clin Invest, December 2000;106(11):1381-1389).

"We recently created a recombinant strain of the fungus lacking the WI-1 adhesion and pathogenicity," they continued. "We show here that administration of viable yeast of this attenuated strain vaccinates against lethal pulmonary experimental infection due to isogenic and nonisogenic strains from diverse geographic regions."

According to the researchers, they have developed the first example of a recombinant attenuated vaccine against fungi. Their vaccine induced delayed-type hypersensitivity and polarized type 1 cytokine responses in experimental animals. These responses are associated with natural disease ...