Medical and Pharmaceutical Biotechnology
This section covers medical and pharmaceutical biotechnology. The exam tests recombinant therapeutics, monoclonal antibodies, diagnostics, gene therapy, and stem cells.
Core rules
Recombinant human insulin is produced by inserting the human insulin gene into E. coli or yeast, expressing the protein, and purifying it. Monoclonal antibodies come from hybridoma cells and have a single specificity. ELISA detects antigens or antibodies through enzyme-linked colour reactions; PCR detects nucleic acid and is often used for confirmation. Gene therapy delivers a functional gene to somatic cells; somatic changes are not inherited, whereas germline changes would be. Stem cells can self-renew and differentiate. Biosimilars are follow-on versions of approved biological products, not identical generics.
Worked example
A patient's serum is positive by ELISA for a viral antigen, and PCR confirms the viral genome. ELISA detects binding between an antibody and antigen, while PCR amplifies a specific DNA or RNA sequence. A positive ELISA alone can be a false positive, so a confirmatory nucleic acid test is used. The reasoning is that ELISA is immunological and PCR is molecular.
Traps that cost marks
Modern recombinant insulin is not extracted from pig pancreas. Antibiotics do not treat viral infections. Gene therapy of somatic cells does not alter the patient's gametes. Monoclonal antibodies are not a mixture of antibodies. Do not call a biosimilar an identical generic.