Complement-fixation and complement-fixation-inhibition titres against the Bedsonia antigen in sera of trachoma patients

Indirect Complement Fixation in Foot-and-Mouth Disease

The coccidioidal complement fixation and immunodiffusion-complement fixation antigen is a chitinase.

Culture filtrates and autolysates of Coccidioides immitis have provided suitable crude antigens for the serodiagnosis and prognosis of coccidioidomycosis. One of these, a heat-labile antigen which participates in the immunodiffusion reaction corresponding to the complement fixation reaction (IDCF), has been characterized as a 110-kDa native protein that, when subjected to reducing conditions an...

The Mechanism of Complement Fixation

1. Complement fixation is obtained in every antigen-antibody reaction involving the presence or formation of a heterogeneous phase (red cells, bacteria, precipitate). 2. The physical constants of fixation (temperature coefficient, velocity, quantitative relationships between the reactants) are those commonly associated with adsorption processes, and are the same in the three types of fixation s...

Indirect Complement Fixation in Foot and Mouth Disease. II. Screening of Cattle Serums

Studies on Complement Fixation

It is shown by complement fixation studies with protein antigens and specific immune rabbit sera that the rate of fixation of complement is determined by the concentration of antibodies in the immune sera, that the greater part of fixation of complement takes place during the 1st hour, and that fixation is practically completed at the end of 4 hours at ice box temperature. It is further shown t...