The storage qualities of a cell-free haemagglutinating antigen of Mycoplasma synoviae for use in haemagglutination inhibition tests

Abstract

Supernatant from Mycoplasma synoviae WVU 1853 broth cultures retained its haemagglutinating activity for more than 18 months when stored at −20 °C or freeze dried and held at +4 °C. Under these conditions it also retained its specificity and sensitivity in haemagglutination inhibition tests against antisera to M. synoviae and M. gallisepticum and known negative sera. Freeze drying thus makes possible the commercial use of liquid residue remaining after harvesting cells for rapid serum agglutination antigen, two products being obtained from one batch of broth culture. Liquid antigen at +4 °C, with or without preservatives, lost HA activity quickly.