A Method for Titrating the Protective Action of Antimeningococcal Serum

Abstract

Miller1 has described a method for the production of experimental meningococcal infection in mice. It consisted in brief of the use of a 6% mucin suspension buffered at 7.4 as a medium in which the organisms were suspended prior to intraperitoneal inoculation. More recently Miller has modified the technique of preparing the mucin.2 A 5% suspension is now prepared, it is sterilized in the autoclave at 10–15 lb. pressure for 15 minutes, sterile dextrose solution is then added to a final concentration of 1%, and the pH adjusted to pH 7.4 with sterile buffer solution.Using such a mucin suspension, the intraperitoneal virulence of meningococcus strains can be titrated,1, 3 and consistent results will be obtained when pure breeds of susceptible mice are employed. It has been found, in accord with Miller's work, that freshly isolated strains may kill when the cultures are diluted as far as 10-8, that is approximately 20 organisms. A brief report has been made elsewhere3 on the application of this experimental me...