Introduction:
This quiz collection on “Conventional vaccine production MCQs With Answer” is designed for M.Pharm students to strengthen conceptual understanding and practical knowledge of traditional vaccine manufacturing. It covers vaccine types (live-attenuated, inactivated, toxoid, subunit, conjugate), upstream and downstream processing, inactivation and attenuation methods, adjuvants and stabilizers, quality control assays, and regulatory considerations. Questions emphasize critical control points such as antigen sourcing, purification, detoxification, potency and sterility testing, residual impurities, and cold-chain/stability aspects. The set aims to bridge theoretical principles and real-world production challenges, helping students prepare for exams and industry roles in vaccine development and quality assurance.
Q1. Which cell substrate is most commonly used for production of traditional influenza vaccines by egg-based methods?
- Vero cell culture
- Chicken embryonated eggs
- HEK293 cell line
- CHO cell line
Correct Answer: Chicken embryonated eggs
Q2. Which inactivation agent is widely used for bacterial toxoid vaccines to detoxify toxins while retaining immunogenicity?
- Sodium dodecyl sulfate (SDS)
- Formaldehyde
- Phenol
- Chloroform
Correct Answer: Formaldehyde
Q3. Serial passage in non-human cells to reduce virulence exemplifies which attenuation method?
- Genetic engineering by site-directed mutagenesis
- Adsorption onto adjuvant
- Cold adaptation via serial passage
- Chemical inactivation with beta-propiolactone
Correct Answer: Cold adaptation via serial passage
Q4. Which assay is commonly used to quantify influenza hemagglutinin antigen potency in conventional vaccines?
- Western blot
- Single radial immunodiffusion (SRID)
- Neutral red uptake assay
- Kjeldahl nitrogen assay
Correct Answer: Single radial immunodiffusion (SRID)
Q5. Aluminium salts used as adjuvants primarily enhance immune response by which mechanism?
- Direct enzymatic activation of complement
- Depot effect and activation of antigen-presenting cells
- Neutralization of endotoxin
- Acting as preservatives to prevent microbial growth
Correct Answer: Depot effect and activation of antigen-presenting cells
Q6. Beta-propiolactone (BPL) inactivation is preferred for some viral vaccines because it:
- Cross-links proteins making antigens insoluble
- Rapidly hydrolyzes to non-toxic products after inactivation
- Causes extensive protein denaturation reducing immunogenicity
- Leaves a persistent chemical residue requiring removal
Correct Answer: Rapidly hydrolyzes to non-toxic products after inactivation
Q7. Conjugate vaccines improve immunogenicity of polysaccharide antigens by:
- Reducing molecular weight to facilitate lymphatic uptake
- Linking polysaccharide to a carrier protein to induce T-cell help
- Encapsulating polysaccharides in alum particles
- Chemically acetylating polysaccharide chains
Correct Answer: Linking polysaccharide to a carrier protein to induce T-cell help
Q8. During downstream processing, which method is most suitable to remove host cell DNA from vaccine bulk?
- Size-exclusion chromatography or nuclease treatment
- Lyophilization
- Use of alum adjuvant
- Thermal annealing
Correct Answer: Size-exclusion chromatography or nuclease treatment
Q9. A critical quality attribute for inactivated whole-cell bacterial vaccines is:
- Residual live bacteria below specified limit
- Presence of lipid nanoparticles
- High plasmid copy number
- Expression of recombinant GFP
Correct Answer: Residual live bacteria below specified limit
Q10. Which stabilizer is commonly added to vaccine formulations to protect antigens during freeze-drying?
- Polyethylene glycol
- Sucrose or trehalose
- Betaine
- EDTA
Correct Answer: Sucrose or trehalose
Q11. The term “sterility testing” for vaccine batches primarily aims to detect:
- Residual formaldehyde
- Presence of replicating microorganisms
- Endotoxin levels
- Protein concentration
Correct Answer: Presence of replicating microorganisms
Q12. Which preservative has historically been used in multi-dose vials but is now limited due to safety concerns?
- Thimerosal (ethylmercury)
- Sodium benzoate
- Phenoxyethanol
- Benzalkonium chloride
Correct Answer: Thimerosal (ethylmercury)
Q13. In live-attenuated vaccine production, stability during storage is best maintained by which approach?
- Continuous exposure to room temperature
- Lyophilization and cold-chain maintenance
- Formaldehyde fixation
- High-salt formulation to prevent viral aggregation
Correct Answer: Lyophilization and cold-chain maintenance
Q14. Residual host cell proteins in vaccine preparations are important because they can:
- Enhance vaccine potency
- Act as potential impurities causing reactogenicity or immune responses
- Neutralize adjuvant activity
- Serve as preservatives
Correct Answer: Act as potential impurities causing reactogenicity or immune responses
Q15. The plaque reduction neutralization test (PRNT) is used to measure:
- Adjuvant particle size distribution
- Neutralizing antibody titers against viruses
- Cell viability in bioreactors
- Endotoxin concentration
Correct Answer: Neutralizing antibody titers against viruses
Q16. During antigen purification, ultrafiltration primarily serves to:
- Denature proteins for detoxification
- Concentrate and diafilter proteins while removing small impurities
- Act as an adjuvant
- Inactivate viral particles
Correct Answer: Concentrate and diafilter proteins while removing small impurities
Q17. For toxoid vaccines, potency release testing commonly relies on:
- Mouse protection or neutralization assays
- Measurement of endotoxin units only
- In-vitro transcription assays
- UV-visible spectroscopy at 280 nm only
Correct Answer: Mouse protection or neutralization assays
Q18. A major regulatory requirement for vaccine batch release includes:
- Documentation of upstream seed lot history and characterization
- Disclosure of all employee names
- Publication of proprietary fermentation recipes
- Use of only glass containers regardless of compatibility
Correct Answer: Documentation of upstream seed lot history and characterization
Q19. Detergent split inactivated vaccines (e.g., split influenza) use detergents primarily to:
- Stabilize live virus in formulation
- Disrupt viral envelopes to reduce reactogenicity while retaining antigenicity
- Enhance bacterial growth in culture
- Increase endotoxin content
Correct Answer: Disrupt viral envelopes to reduce reactogenicity while retaining antigenicity
Q20. Antigenic drift affects conventional vaccine production by necessitating:
- Permanent elimination of seasonal vaccine programs
- Periodic updating of vaccine strains and potency testing to match circulating variants
- Use of a single universal antigen for all seasons
- Switching from inactivated to live vaccines only
Correct Answer: Periodic updating of vaccine strains and potency testing to match circulating variants
