Accession Number : AD0838812

Title :   INTERACTION OF VENEZUELAN EQUINE ENCEPHALOMYELITIS VIRUS WITH NEUTRALIZING ANTIBODY. I. NEUTRALIZATION KINETICS AND REACTION REVERSIBILITY,

Corporate Author : FORT DETRICK FREDERICK MD

Personal Author(s) : Hahon, Nicholas

Report Date : JUN 1968

Pagination or Media Count : 31

Abstract : The neutralization of Venezuelan equine encephalomyelitis (VEE) virus follows first-order kinetics with the reaction rate dependent on the antibody concentration and the reaction temperature, but independent of pH and virus concentration within the prescribed limits. The linear relationship obtained between the neutralization reaction rate constant (K) and antiserum dilution showed that K increased fivefold for each tenfold dilution of antiserum. By an Arrhenius plot, a linear function between the logarithm of K and the reciprocal of the absolute temperature of reaction was demonstrated. The energy of activation was calculated to be approximately 9,000 calories per mole of virus. Each 10 C change in temperature altered the K value by a factor of 1.7. In the presence of excess antibody, a small fraction of virus resisted neutralization. Neutralized virus could not be appreciably reactivated by simple dilution under physiological conditions but was dissociated at either acid or alkaline pH. Reneutralization of virus occurred when the environmental medium was adjusted to neutrality, indicating that reactivation was the result of dissociation and not denaturation. Neutralized virus can be attached to cell monolayers and reactivated to an infectious state by treatment at acid pH. The relationship of these findings to current views of virus neutralization and the advantages of the VEE virus-antibody system in conjunction with the fluorescent cell-counting viral assay for studies of neutralization reactions are discussed. (Author)

Descriptors :   (*VENEZUELAN EQUINE ENCEPHALOMYELITIS VIRUS, ANTIGEN ANTIBODY REACTIONS), NEUTRALIZATION, REACTION KINETICS, TEMPERATURE, PH FACTOR, IMMUNE SERUMS, MATHEMATICAL ANALYSIS, DISSOCIATION, COUNTING METHODS, BIOASSAY.

Subject Categories : Microbiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE