I&D Notes: Humoral Immunity (B cells)

Y1, I&D, IND, infection and defence, I+D, I and D,  Y1Bcells, I&D, Benny Chain

Functions of Antibodies:
• neutralisation- antibodies (IgG) bind to toxins or viruses to prevent entry to cell
• opsonisation- antibodies (IgG) coat bacteria, allowing neutrophils to
phagocytose them
• complement activation- (IgM) activates classical pathway

Class Switching:
• IgM is switched to other antibodies (IgG)
• some cells become plasma cells or memory cells
• Uses the enzyme AID
Affinity Maturation:
• occurs in secondary immune response
• affinity maturation is the way antibodies develop their affinity to antigens
• it uses the process of somatic hypermutation to increase affinity
• somatic hypermutation occurs in germinal centres of secondary lymphoid
organs (uses AID)
Primary and Secondary Immune Response:
• primary response is when body first encounters antigen
• secondary response is when the body encounters antigen again and has a
stronger immune response

I&D: Immunology – Humoral Immunity:
antibody mediated responses

Monoclonal antibodies attack one type of antigen
Polyclonal antibody response in normal immune response