Question

Given below are the different steps involved in the process of obtaining therapeutic gene products from genetically modified cells, at a large scale.

1. Separation of product from the culture media
2. Culturing genetically modified cells in bioreactors
3. Clinical trials of the product
4. Purification of the product
5. Taking measures for quality control
6. Formulating the product with suitable preservatives

Select the option which correctly represents the order in which these steps are conducted.

• A. 2→3→5→6→1→4
• B. 2→1→4→6→3→5
• C. 4→5→6→3→2→1
• D. 3→6→5→4→1→2

Answer 1

The correct option is B 2→1→4→6→3→5

Obtaining a therapeutic gene product from a living source, here, genetically engineered organism, is known as bioprocessing. It consists of two stages- upstream processing and downstream processing.

Upstream processing involves the growth of cells in large bioreactors.
Once the concentration or density of the product expressed by the host cells in the culture reaches the optimal quantity, it needs to be extracted out for use. Separation of the expressed gene product from the culture media and its purification are done. These are the components of downstream processing.

Next the product is formulated with preservatives to increase its shelf life. This is followed by strict clinical trials, especially if the desired gene product is a drug. Based on the results of the clinical trials, further quality control measures are taken to ensure that the product is ready to be marketed for commercialization.

Thus, the correct order of the steps involved in the process of obtaining a desired gene product from genetically modified cells, at a large scale, is as follows:

-Culturing genetically modified cells in bioreactors (2)
-Separation of product from the culture media (1)
-Purification of the product (4)
-Formulating the product with suitable preservatives (6)
-Clinical trials of the product (3)
-Taking measures for quality control (5)