Immunopathology Flashcards
Specific (adaptive) immunity components
Macrophages and dendritic cells
Macrophages and dendritic cells:
- process (break down) and present antigens to T cells (apc’s)
- become effector cells (more destructive) in cell mediated immune response.
Specific (adaptive) immunity components
Antigen (Ag)
- protein or polysaccharide
- Ag processing or presenting
- apc’s- macrophages, dendritic cells, B cells
Specific (adaptive) immunity components
Antibodies (Abs)
- aka immunoglobin
- two heavy chains, two light chains, prong on top which is binding site
- synthesised and secreted by plasma cells
- formed against ags in the ecf.
- 5 classes:
IgA- secreted in breadt milk, mucus, tears and other body secretions
IgE- bind specifically to mast cells via their Fc stems. Associated with type 1 hypersensitivity.
IgG- Crosses placenta. Neutralises toxins, characteristics of secondary Ab immune response.
IgM- characteristic of primary Ab immune response. - Histocompatibility Ags
Class 1 Ags: found on all nucleated cells and platelets, present to cytotoxic cell.
Class 2: found only on Apc’s, often associated with autoimmune diseases, present to helper cell
Importance in transplantation, immune responses, disease susceptibility/ protection.
Specific immune response- antibody mediated (humoral)
Primary and secondary immune response
AB-Ag activates complement cascade.
- act as opsonins
- neutralise substances eg toxins
Specific immune response- cell mediated
Cells that kill are-
Cytotoxic T cells
NK cells and macrophages which become effector cells- kill cancer cells and virally infected cells
Do form antibodies against viruses but they are non- functional
Specific (adaptive) immunity
Produces antibodies against agents.
Lymphoid organs:
primary: thymus, bone marrow (supplies thymus with cells)
Peripheral:
Spleen, tonsils, adenoids, lymphatic system, lymph nodes
Lymphocytes:
B Cells 10-20% in circulation
T Cells 60-70% in circulation- helper (CD4+), cytotoxic (CD8+)
NK cells 10-15% in circulation
