Complement fixation with antigens prepared from bluetongue virus-infected mouse brains

Abstract

Six strains of bluetongue virus were compared by cross complement-fixation tests performed on Perspex sheets according to the method of Fulton & Dumbell using antigens derived from crude saline extracts, and acetone and ether extracts, of infected suckling mouse brains. Only minor differences were encountered with the former and no significant differences with the latter. The reasons for this are discussed.In the neutralization tests important differences were demonstrated between strains.There is evidence that the soluble antigen is composed of particles of varying size, that the smaller particles are responsible for the marked overlapping in the complement-fixation tests, and that increasing complexity associated with increasing particle size may be concerned with increasing serological specificity.