Controlling BCG Vaccine’s Cell Viability in the Process of Its Production by an Bioluminescent ATP Assay

The Bacille Calmette–Guerine (BCG) vaccine, which is based on a live strain of Mycobacterium bovis BCG is widely used for the immunoprophylaxis of tuberculosis. One of the BCG vaccine’s key parameters is its сell viability (specific activity: the number of colony forming units, CFUs), which is traditionally defined by the microbiological method. In this work, the rapid and selective bioluminescent method of intracellular ATP assay is used to control the BCG vaccine’s viability at various stages of the vaccine’s production. It permits us to reduce the time required for the analysis from 28 days to 1 h. The correlation is shown between the viability of a liquid BCG vaccine measured by the microbiological method compared to one calculated using the content of intracellular ATP, as well as the correlation between the CFU value for the lyophilized BCG vaccine and the ATP content in the liquid vaccine before lyophilization.