Monoclonal antibodies: what does “monoclonal” specifically imply in immunotechnology? Choose the most comprehensive definition that captures the properties of monoclonal reagents.
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AA single clone of antibody-producing cells
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BAll antibody molecules are identical
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CBind the same antigenic site with identical affinity
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DAll of the above
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EDerived only from rabbits
Answer
Correct Answer: All of the above
Explanation
Introduction / Context:Monoclonal antibodies transformed diagnostics and therapy by providing uniform, highly specific reagents. Understanding what “monoclonal” entails helps explain their reproducible performance across assays and lots.
Given Data / Assumptions:
- Hybridoma or recombinant methods generate antibodies from a single B-cell clone.
- Resulting antibodies share identical amino acid sequences in their variable regions.
- They recognize the same epitope and display the same affinity under defined conditions.
Concept / Approach:“Monoclonal” denotes origin from one clone. This implies sequence identity, epitope specificity, and uniform affinity. In contrast, polyclonal sera contain a mixture of antibodies with multiple specificities and affinities, which can vary between animals and bleeds.
Step-by-Step Solution:Relate monoclonality to a single ancestral B cell.Infer identical variable regions lead to identical binding properties.Conclude that all statements describing same clone, identical molecules, and same antigenic site are simultaneously true.
Verification / Alternative check:Sequencing and isotyping of monoclonal preparations reveal uniform V-region sequences and consistent isotype, confirming identity and epitope specificity.
Why Other Options Are Wrong:“Derived only from rabbits” is false; mice, rats, humans, camelids, and recombinant platforms are widely used.
Common Pitfalls:Assuming identical affinity in all buffers and temperatures; affinity can be context dependent even if paratope–epitope pairing is the same.
Final Answer:All of the above.