| Abstract: | The authors present a method of obtaining relatively homogeneous preparations of alpha-toxoid of Cl. perfringens, type A, including the primary conception of the alpha-toxin proteins, their chromatography on DEAE-cellulose, fractionation with (NH4)2SO4, detoxication, with the subsequent gel-filtration through sephadex and isoelectric focussing. Sedimentation coefficient of the preparation proved to be 3.8 S, isoelectric point-4.83 +/- 0.07. In studying the immunogenic properties of alpha-toxoid in experiments on guinea pigs and rabbits their high immunogenicity, exceeding that of the industrial toxoid 8- and 6-fold, respectively, was established. Homogeneous preparations of alpha-toxoid provided intense anti-microbial immunity. Interlinear differences in the levels of the immune response of inbred mice, highly-reactive (BALB/c) and low-reactive (C57BL/6) to alpha-toxoid, reached 20-fold; in combination with the high immunogenicity of this antigen for mice this permits to recommend it for immunogenic studies. |
