Biotechnology Quiz: Antibodies & Protein Sorting

Anti-bodies Production

• Hybridoma cells are produced by fusing B-lymphocytes with myeloma cells, allowing for the production of monoclonal antibodies.
• HAT medium is essential for isolating hybridoma cells; it supports the growth of hybrid cells while inhibiting the unwanted cells.
• Hybridomas are capable of producing large quantities of monoclonal antibodies for therapeutic and diagnostic applications.

Protein Sorting and Secretion Pathways

• Protein sorting refers to the mechanism that directs proteins to their proper locations within or outside the cell based on intrinsic signals within the protein.
• Key signal types include:
  • Signal Sequence: Peptide at the N-terminus guiding proteins to the secretory pathway.
  • Mitochondrial Targeting Signal (MTC), Nuclear Localization Signal (NLS), and Peroxisomal Targeting Signals (PTS) direct proteins to mitochondria, nucleus, and peroxisomes respectively.
• Post-translational translocation is a process where proteins synthesized in the cytosol are transported to organelles like mitochondria, chloroplasts, or peroxisomes.

Vaccines Types

• Attenuated Vaccines: Contain live pathogens with modified virulent genes (e.g., cholera). Risks include the possibility of causing the disease if the pathogens are not sufficiently attenuated.
• Subunit Vaccines: Utilize specific viral antigens or microbial proteins rather than whole organisms, exemplified by the hepatitis B virus vaccine.
• Vector Vaccines: Employ a non-pathogenic virus (such as vaccinia) to deliver genes for foreign antigens, stimulating an immune response.

Plant Genetic Manipulation

• Plant cells are cultured as suspension cultures in liquid medium or as callus cultures on solid medium. Achieving the right auxin and cytokinin balance is crucial for cell differentiation.
• Arabidopsis thaliana is a favored model for gene transfer studies due to its rapid growth and small genome size. It often uses Agrobacterium tumefaciens for gene introduction.

Plant as Bioreactors

• The first plant-produced pharmaceutical product was human growth hormone from transgenic tobacco in 1986.
• Plant bioreactors are advantageous for:
  • Cost-effectiveness and scalability.
  • Post-translational modifications.
  • Absence of animal pathogens.
• Challenges include low yield of recombinant proteins and susceptibility to proteolytic degradation.
• Strategies for improving yields involve reducing protease activity and using proteinase inhibitors during culture and extraction.

Stem Cells Overview

• Stem cells have the capabilities of self-renewal and potency, enabling them to maintain their population and differentiate into various specialized cell types.
• Totipotent stem cells can form both embryonic and extra-embryonic tissues. They arise from the fertilization of an egg and can develop into a complete organism at the morula stage.

Test your knowledge on the production of monoclonal antibodies and the mechanisms of protein sorting and secretion pathways. This quiz covers the essentials of hybridoma cells, HAT medium, and the various targeting signals for proper protein localization. Challenge yourself and see how well you understand these key biotechnological processes!