Size Matters: Measurement of Capsule Diameter in Cryptococcus neoformansTiffany Guess 1, Hoyin Lai 2, Serenah E. Smith 1, Linda Sircy 1, Kirsten Cunningham 1, David E. Nelson *1, Erin E. McClelland *1
1Department of Biology, Middle Tennessee State University, 2DRVision Technologies
The polysaccharide capsule is the primary virulence factor in Cryptococcus neoformans, and its size correlates with strain virulence. Capsule diameter measurements are used in phenotypic testing and to gauge therapeutic efficacy. Here a standard method of capsule induction is presented, and two methods of staining and measuring diameter are compared.