[Study of the immunological properties of Actinomyces rimosus ribonuclease]

The immunological properties of ribonucleases from Act. rimosus were studied in comparison with RNA-ase from the cattle pancreas. The activity of anti-RNA-ase immune sera were determined by the method of specific neutralization of the effect of the above exzymes. The results of the study showed that with the use of homological RNA-ases as the antigens, the maximum level of enzymatic activity neutralization by the immune sera ranged within 70 to 90% and the capacity for induction of specific antibody production expressed in the serum titer was somewhat lower in the actinomycete RNA-ase than in the pancreatic one. When heterological antigens were used, neutralization of the RNA-ase effect by the immune sera was either not detectable or very low which is indicative of the antigenic differences in the actinomycete and pancreatic RNA-ases.