Are Clones Really Unstable

Selection of a stable clone is one of the most essential criteria for the successful production of any therapeutic protein. The stability of the clone needs to be evaluated in terms of various parameters like cell growth, specific cell productivity (PCD) and product characteristics with increasing generations. To generate sufficient amount of inoculum for the production bioreactor, cells from cell bank are periodically sub-cultured which in turn increases the generation number. Thus the clone needs to be stable for multiple generation numbers. In this study a stability programme has been designed which is based on the use of a scale down model of inoculum generation and the manufacturing process. The stability of the clones also showed a correlation with the diameter of the cells during sequential passaging. It was shown that choice of appropriate medium used for cell passaging make these clones stable.