Rabies vaccines produced in cell culture

Abstract

Summary In 1953, Sanders et al. published the first trial of adapting rabies virus to cell culture. The adapting of rabies virus to diploid cells of human origin by Wiktor et al. in 1954 gave new possibilities. Other cell systems were then explored in different countries. A list of the cells recommended by the WHO Expert Committee was drawn up in 1974. The cell culture vaccines used regularly for human vaccination are classifiedaccording to their cell support: a ) primary cells of animal origin: cells from hamster kidney, fœtal calf kidney and dog kidney; b ) cells from bird embryos: chicken or quail; c ) diploid cells: essentially of human origin, WI38, then MRC5 and, on trial, rhesus diploid cells; d ) heteroploid cells: Vero cells. Three examples illustrate the points in common and the differences in the culturesystems and the corresponding vaccines: u -vaccines produced from human diploid cells, the most widely used in the world, acting as a reference for cell culture vaccines; -vaccines produced from fœtal calf kidney cells, an example of productionusing a primary animal cell system; -vaccines produced from Vero heteroploid cells, which paved the way to large-scale industrial production. Cell culture vaccines have transformed the possibilities of immunization beforeand after exposure. But these vaccines only account for 7% of antirabies treatment at present, with enormous variations, principally depending on the economic possibilities of the different regions of the world. Future development, based on the recommendations made in 1984 by the WHO Rabies Expert Committee, should resolve the technical and economic problems, making it possible to replace traditional vaccines by cell culture vaccines.