ADAPTIVE IMMUNE RESPONSE

ADAPTIVE IMMUNE RESPONSE

1. Development of T and B cells

   • Lymphocytes
     • T cells
     • B cells
   • antigent-independent maturation occurs in :
     • T cells in thymus
     • B cells in bone marrow
   • Markers or receptors
     • Bind to receptors on the other cells
     • Bind to antigens
     • Transmit and receive mesaages
   • Common receptor molecule
     • major histocompatibility complex (MHC)
       • Class 1
         • expressed on all nucleated cells
       • Class 2
         • on antigen-presenting cells
           • macrophages
           • dendritic cells
           • B cells
       • Class 3
         • on proteins associated with the complement system
     • Cluster of differentiation (CD)
       • over 300 CD molecules identified
       • CD4 binds to MHC class 2
       • CD8 binds MCH class 1
     • Antigen-specific receptors
   • have antigens specific receptors
     • recognize one type of unique antigens
     • key shapes (receptor) and lock shapes (antigens)
     • carrying one specific
   • clonal deletion
     • eliminate lymphocytes that recognise self antigen

2. presentation of antigens

   • antigens : substance that can provoke immune response
     • one antigen may have one epitope
     • antigenicity
       • size
       • Complexity
       • Foreigness
     • antigen- presenting cells
       • Macrophages
       • Dendritic cells
       • B cells
       • Roles :
         • phagocytosis of enemy cell
         • fusion of lysosome and phagosome
         • enzymes start to degrade enemy cell
         • enemy cell broken into small fragments
         • fragments of antigen presented on APC surface
         • Leftover fragments released by exocytosis
   • epitopes : the part of an antigen molecule to which an antibody attaches itself

3. T cells response

   • activation stimulates into :
     • subtypes of T helper cells
       • stimulate the other cells
         • macrophages
         • B cells
         • Tc cells
     • Memory T cells
       • store immunological memory
     • Regulatory T cells
       • cativate other cell to prevent excessive inflammation and autoimmunity
     • Cytotoxic T cells
       • infected host cell
       • cancerous host cell
       • foreign cell for other humans or animals

4. B cells response

   • can be activate without the help of T helper cell
   • differentiate
     • memory B cells
       • store immunological memory
     • Regulatory B cells
       • regulate other cells to prevent excessive inflammation
     • Plasma cells
       • Launch billions of antibodies to attack the invader
         • Neutralisation
         • Opsonisation
         • Agglutination
         • Antitoxin action