The aim of the release testing of a vaccine batch is to show that this batch is consistent with and equivalent to the successive batches produced by the manufacturer and to the batches that have been shown safe and efficacious in clinical trials in man. This validated assay mimics the in vivo process of vaccine uptake and cellular effect. The vaccine uptake and infectivity of test batches are compared to those of reference material.
In vitro system of human mononuclear cells (U937).
The cells are differentiated in vitro, infected with test and reference batches and the infectivity and uptake by the cells is determined by plating and CFU counting method.