The spiroplasma deformation test,a new serological method

The deformation test is a simple and highly sensitive technique capable of demonstrating significant antigenic differences among helical, wall-less prokaryotes (spiroplasmas). Specific identified. Quantitative relationships among various antisera are determined by examining, under dark-field microscopy, samples containing serum dilutions and a measured number of organisms which is held constant in each test. Antisera dilutions of 1:2,000 to 1;16,000 deformed spiroplasmas in homologous tests involvingSpiroplasma citri and the corn stunt and suckling mouse cataract spiroplasmas. With the exception of some heterologous cross-reactions in the deformation test betweenS. citri and corn stunt spiroplasmas, antisera and preimmunization sera failed to deform heterologous spiroplasmas at dilutions higher than 1:16.