Topic 39 of 66 in the MU Plovdiv syllabus for Human Biology (Dental Medicine, Year 1). The free AceMed note covers it in 25 sections, about 2,392 words (18 min of reading), with 22 flashcards.
In this note
Structure of antibodies
General Characteristics of Antibodies
Formation and Types
Basic Structure: Polypeptide Chains and Overall Shape
Chain Arrangement and Bonding
Domain Architecture
Antigen Binding Regions
Constant Region Functions
Membrane-Bound vs. Soluble Forms
Antibody Isotypes and Their Structural Variations
Oligomeric Forms
Glycosylation and Solubility
Enzymatic Fragmentation and Structural Analysis
Monoclonal Antibodies
MNEMONIC
Functions of antibodies
Understanding the Multifaceted Functions of Antibodies
Direct Functions: Neutralizing and Blocking Threats
Indirect Functions: Enlisting the Innate Immune Army
Complement Activation via the Classical Pathway
Specialized Roles of Different Antibody Classes
Natural Antibodies: Born Ready
When Antibodies Go Wrong: Hypersensitivity Reactions
MNEMONICS
Molecules of cell-mediated immunity.
Structure of antibodies
Structure of Antibodies (Immunoglobulins)
General Characteristics of Antibodies
Antibodies, scientifically known as immunoglobulins (Ig), are glycoproteins produced by B lymphocytes.
They are central to humoral immunity, the aspect of the immune system that combats pathogens in bodily fluids.
The term "Ab" is often used in the context of function (e.g., antigen neutralization), while "Ig" is used to describe structural and classification features.
Formation and Types
B cells initially express antibodies as membrane-bound receptors embedded in their plasma membrane.
Upon recognizing a specific antigen, the B cell becomes activated and differentiates into a plasma cell, which secretes soluble antibody molecules into the bloodstream.
Soluble antibodies retain the same antigen specificity but lack the transmembrane region due to alternative RNA splicing during post-transcriptional processing.
Basic Structure: Polypeptide Chains and Overall Shape
Each antibody is a quaternary protein complex consisting of four polypeptide chains:
Two identical heavy chains (larger, around 50 kilodaltons)
Two identical light chains (smaller, around 25 kilodaltons)
These four chains are linked by disulfide bonds, which provide structural integrity.
The molecule has a Y-shaped configuration, symmetrical in structure.
Continue reading free
The whole note, all 25 sections, is free with an AceMed account, with its 22 flashcards. Premium adds flashcard recall, highlights and Ask AI.