Determination of residual virulence and immunogenicity of Mycobacterium bovis BCG-1 seed lots

Abstract

The article is devoted to a challenging issue of stability of seed lot systems that have been used in Russia since 1947 to produce BCG vaccines. This problem is underexplored and needs further investigation. In an earlier study the authors of the article used innovative (molecular genetic) methods to demonstrate the conformity of BCG-1 seed lots used in Russia to the international reference reagent ( BCG Vaccine of Russian BCG-I sub-strain-International Reference Reagent ) in terms of «Identification». This article lays out the results of new comparative studies of BCG-1 367 «shch» (1982) and 368 «shch» (2006). During the study special emphasis was put on such quality parameters as residual virulence (survival), specific safety (absence of virulent mycobacteria tuberculosis), sensitization effect (by induction of immune-mediated delayed hypersensitivity to tuberculin), and protective effects. The values obtained in the batches evaluation were very close and did not differ from the results obtained during certification performed just after the production of each seed lot. These results testify to the high degree of stability of the seed lots biological properties. The article also cites literary sources that address the issue in question.

Keywords

• вакцина бцж
• субштаммы бцж
• система посевных серий
• остаточная вирулентность
• приживаемость
• bcg vaccine
• bcg substrains
• seed lot system
• residual virulence
• survival