Question

1. Typically once a successful host strain that will produce heterologous protein is created, a large batch of the recombinant organism is grown and a master cell bank is produced. Every time a batch of product is manufactured, the technicians go back to that master cell bank to produce the start-up culture. Why don’t they just take an aliquot of each batch after each run to use as the start-up culture, instead of starting over with frozen glycerol stock every time?

Answer 1

CELL GROWTH IN MEANS CELL DIVISION. AND CELL DIVISION INCLUDED MUTATION AND RECOMBINATION OF GENETIC MATERIAL. MORE THE CELL DIVISION MORE WILL BE THE CHANCES FOR RECOMBINATION OR MUTATION AND MAY RESULTING IN LOSS OF RECOMBINANT EXPRESSION. MASTER CELL BANK IS STORED IN LOW TEMPERATURE WITH GLYCEROL AS CRYOPROTECTIVE AGENT HELPING IN SURVIVAL AND PREVENTING THE GROWTH OR CELL DIVISION TO MINIMUM THUS KEEPING CELL RECOMBINANT GENE UNALTERED. THAT IS WHY EACH LARGE BATCH TAKE INNOCULA FROM MASTER CELL BANK NOT THE SMALL PORTION OF PREVIOUSLY LARGE BATCH WHICH HAS UNDERGONE SO MANY CYCLE OF CELL DIVISION.