Kolybo D. The molecular mechanisms of diphtheria toxin immune recognition

The work is devoted to delineating the role of molecular mechanisms of diphtheria toxin (DT) immune recognition, determined by the DT biological properties. This is important for the development of new tools for diphtheria diagnosis. Recombinant derivatives of DT functional fragments were used to analyze the mechanisms of DT immune recognition as well as DT-specific immune response. It was shown that differences in the sensitivity to DT of mouse and monkey cells could be due not only to different toxin binding affinity to the cell receptors, but also to the processes that take place after toxin penetration into the cell. The role of DT in suppressing of DT-specific immune response was shown. Immunoenzyme tests as well as rapid tests for the detection of DT and DT subunit-specific antibodies were developed in the course of the work, which could be used to improve the diphtheria diagnostics. Keywords: diphtheria toxin, immune recognition, molecular mechanisms, recombinant antigens and antibodies.