17/1 Adaptive immunology Flashcards
Adaptive immunology involves:
lymphocytes ( T & B Cells), highly specific antigen recognition, cytokines & collaboration with other cells
All immune responses can be divided into:
cell mediated and humoral immunity
cell mediated immunity
all responses in which antibodies play little/no part; involves T cells, macrophages, neutrophils, NKs
Humoral immunity
antibody mediated ( B cells)
define antigen
any substance that binds to specific receptors on lymphocytes i.e B cell/ T cell receptors
antigen can be many forms. List some
- may be protein, lipid, carbohydrate or any combination
- may be foreign or altered self molecule
- may be soluble or particulate, simple or complex with many diff. antigenic determinants
define antigenic determinant/ Epitope
part of antigen that binds to these receptors
any molecules or group of molecules that induce an immune response
immunogen
small molecule that can act as an epitope but not elicit an immune response
hapten
non microbe derived antigens might include?
pollen, food & dust or ‘self’ antigens from dead/ senescent cells or altered self molecules
non microbe derived antigens might include?
pollen, food & dust or ‘self’ antigens from dead/ senescent cells or altered self molecules
antigens can enter the body by various methods. List some
Breaks in skin & mucous membranes
Direct injection e.g. bite/needle
Organ transplants & skin grafts
Microfold cells in the mucosal surfaces
structure of antibody
Monomer: flexible Y-shaped molecule with 4 protein chain
Has variable region, constant regions, Fc region
what is the 4 protein chain in antibody structure?
2 identical light chains
2 identical heavy chains
Variable region in antibody structure
2 sections at the end of the Y arms
- contain antigen binding sites
- identical on the same antibody, but vary from one antibody to another- contains some hypervariable regions
constant region in antibody structure
stem of monomer on lower part of Y’s arm
Fc region on antibody structure
stem of monomer only
why is the Fc region important?
because they can bind to complement or cells
5 different classes of antibodies
IgG, IgM, IgA, IgE, IgD