Characterization of Antibodies Produced by Guinea Pigs Inoculated with Inactivated Foot-and-Mouth Disease Antigen

Abstract

Two types of neutralizing antibodies with markedly different physical-chemical and complement-fixing properties are found after inoculation of guinea pigs with inactivated foot-and-mouth disease virus. One, present during the 1st and 2nd week after inoculation, is of 19 S class sedimentation, of high adsorption to DEAE-cellulose, of β-globulin electrophoretic mobility, noncomplement fixing, and precipitation with viral antigen in agar gel. The other, appearing during the 2nd week after inoculation and continuing in excess of 30 days, is of 7 S class sedimentation, is poorly adsorbed on DEAE-cellulose, is of γ-globulin electrophoretic mobility, fixes complement readily and also precipitates with viral antigen in agar gels. Because of this marked change in their properties, it was concluded that quantitative studies of neutralizing antibody to assay antigens could not be done during the first three postinoculation weeks.