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Introduction to Immunoanalysis

• Immunoanalysis is a field focusing on the detection and measurement of molecules using antibodies.
• Monoclonal antibodies (mAbs) are key tools in this field.

Learning Objectives

• Describe the characteristics of mAbs.
• Understand the meaning of mAb suffixes (omab, ximab, zamab, umab).
• Define naked mAbs, conjugated mAbs, and bispecific mAbs.
• Explain the process of mAb generation.
• Compare and contrast the use of mAbs and polyclonal antibodies (PAbs).

Monoclonal Antibodies (mAbs)

• mAbs are secreted by a single plasma cell clone.
• They are derived from a single B-lymphocyte precursor.
• They are produced by plasma B cells cultured in a lab.
• These specialized cell lines are known as hybridomas.
• Hybridomas secrete only one unique antibody type.
• mAbs are homogeneous, targeting a single epitope on an antigen molecule.

mAb Therapeutics - Suffixes of Relevance

• Omab (Murine): Derived from mouse proteins.
• Ximab (Chimeric): A combination of mouse and human proteins.
• Zumab (Humanized): Contains small portions of mouse proteins combined with human proteins.
• Umab (Human): Composed entirely of human proteins.

mAbs for Oncology

• mAb therapeutics are used to treat various cancers like lung cancer, brain tumors, ovarian cancer, breast cancer, gastric cancer, melanoma, colorectal cancer, Hodgkin's lymphoma and others.
• Naked mAbs: Used as standalone therapy.
• Conjugated mAbs: Modified with radioactive particles or drug compounds to enhance therapeutic impact.
• Bispecific mAbs: Designed to target two different antigens simultaneously, boosting immune cell activity against the tumor.

Monoclonal Antibody Production - Steps

• Step 1: Immunization and Isolation of Splenocytes: Immunizing animals (e.g. mice) to stimulate antibody production against a specific antigen, followed by blood collection and isolation of antibody-producing splenocytes.
• Step 2: Preparation of Myeloma Cells: Immortalization of myeloma cells for prolonged growth in the lab.
• Step 3: Fusion: Fusing the antibody-producing splenocytes with immortalized myeloma cells to create hybridomas.
• Step 4: Clone Screening/Selection: Screening resulting hybridomas for the desired antibody production based on antigen specificity.
• Step 5: Functional Characterization: Confirming and validating the characteristics of high-producing clones (e.g., ELISA).
• Step 6: Scale Up and Wean: Increasing the production scale and eliminating selection agents to create uniform antibody production.
• Step 7: Expansion: Scaling up antibody production using advanced systems like bioreactors.

Advantages of mAb Production

• Batch-to-batch reproducibility (high homogeneity).
• Large-scale production is possible.
• Low cross-reactivity, high specificity to a single epitope of the antigen.
• Increased sensitivity for quantifying protein levels.
• Low background noise.

Limitations of mAb Production

• High production cost.
• Requires significant time (6 months) for developing hybridized clones.
• Susceptibility to binding alteration when tagged/labeled.

Compare/Contrast MAbs and PAbs

• mAbs exhibit high specificity, compared to PAbs which recognize multiple epitopes.
• The creation of mAbs is more complex and more expensive, while PAbs are produced more readily but less specifically.
• mAbs offer higher reproducibility, whereas PAbs vary in the antibody population.

Global Market for mAb Production

• The monoclonal antibody market is predicted to exhibit robust growth.
• Significant global market size is forecast.
• Growth is expected across several medical areas.

Explore the fascinating field of immunoanalysis, focusing on the characteristics and applications of monoclonal antibodies (mAbs). This quiz covers the generation process of mAbs, their various types and suffixes, and how they compare to polyclonal antibodies. Test your knowledge and understanding of these critical tools in molecular detection.