Simplified method for the production of carbohydrate antigen from Neisseria meningitidis

Abstract

The Gotschlich procedure for the production of carbohydrate antigens from the supernatant fluids of cultures of Neisseria meningitidis groups A and C was modified. Steps involving digestion with nucleases and gel filtration through Sephadex G-50 were added, the number of extractions was greatly reduced, and high-speed centrifugations were eliminated. The antigens thus obtained appeared to be entirely comparable to those described by Gotschlich et al. in physical, chemical, and antigenic properties. A slight degree of protection of mice was repeatedly demonstrated with extraordinarily large doses of antigen (50 mug/mouse), but not with smaller doses. Toxicity of the antigens for laboratory animals was very slight.