50. Immune response - diversity and memory. Primary and secondary response, cellular and humoral response. Flashcards
1
Q
- Specificity: able to distinguish among different antigens and so it is defined by the epitopes. It’s not complete (cross reactivity)
- Adaptiveness: ability to respond to previously unseen invaders
- Discrimination between “self” and “non-self”
- memory: ability to recall previous contact with a foreign molecule and respond in a “learnt” way
A
- Specificity: able to distinguish among different antigens and so it is defined by the epitopes. It’s not complete (cross reactivity)
- Adaptiveness: ability to respond to previously unseen invaders
- Discrimination between “self” and “non-self”
- memory: ability to recall previous contact with a foreign molecule and respond in a “learnt” way
2
Q
Primary immune response
- refers to the period where the body first encounters the foreign antigen and reacts to it developing memory
Secondary immune response
- when the body encounters the antigen again, developing a larger, stronger and quicker response
A
Primary immune response
- refers to the period where the body first encounters the foreign antigen and reacts to it developing memory
Secondary immune response
- when the body encounters the antigen again, developing a larger, stronger and quicker response
3
Q
Lines of defence
1st line:
- non-specfic
- including skin, mucous membranes and body fluids 2nd line:
- Including Natural Killer cells, macrophages, complement system, interleukins, neutrophils, interferon
- Cellular response
3rd line:
- Specific, including humoral response
- T Cells and B cells activated by antigen presenting cells
A
Lines of defence
1st line:
- non-specfic
- including skin, mucous membranes and body fluids 2nd line:
- Including Natural Killer cells, macrophages, complement system, interleukins, neutrophils, interferon
- Cellular response
3rd line:
- Specific, including humoral response
- T Cells and B cells activated by antigen presenting cells
4
Q
Cellular response
- carried mainly by T lymphocytes which have many identical non-selected receptors and circulate directly through the site
- T helper cells: co-operate with B cells to enhance production of antibodies, they release substances (lymphokines) that provide activation sequels for B cells
- TDTH (delayed type hypersensitivity cells): produce inflammation by inducing migration and activation of macrophages and monocytes
- Tc (cytotoxin): upon direct contact, they release substances to kill the cells
- Ts (T-supressor): shut down the immune response
A
Cellular response
- carried mainly by T lymphocytes which have many identical non-selected receptors and circulate directly through the site
- T helper cells: co-operate with B cells to enhance production of antibodies, they release substances (lymphokines) that provide activation sequels for B cells
- TDTH (delayed type hypersensitivity cells): produce inflammation by inducing migration and activation of macrophages and monocytes
- Tc (cytotoxin): upon direct contact, they release substances to kill the cells
- Ts (T-supressor): shut down the immune response
5
Q
Humoral response
- involves the production of antibodies by B cells and clonal selection theory
Clonal selection theory:
- antibody and lymphocytes of countless specificity exist before any contact with foreign antigens
- lymphocytes have antigen receptor sites
- each lymphocyte carries receptor molecules of a single specificity
- immunocompetent lymphocytes proliferate and differentiate into clones of cells making antibodies
- circulating “self” antigens reach the developing lymphoid system for it to recognise them and not induce an immune response later on. Lymphocytes potentially react with “self” are deleted or inactivated
- binding of the antibodies to the foreign antigens causing neutralisation, opsonisation (make a cell more susceptible to phagocytosis) and complement system activation.
- causes the lysis of cell or enhance phagocytosis
- activation of complement system - results in polymorphonuclear cells
Inflammatory response - histamines, phagocytotic cells and fever may all play a role in local inflammations
A
Humoral response
- involves the production of antibodies by B cells and clonal selection theory
Clonal selection theory:
- antibody and lymphocytes of countless specificity exist before any contact with foreign antigens
- lymphocytes have antigen receptor sites
- each lymphocyte carries receptor molecules of a single specificity
- immunocompetent lymphocytes proliferate and differentiate into clones of cells making antibodies
- circulating “self” antigens reach the developing lymphoid system for it to recognise them and not induce an immune response later on. Lymphocytes potentially react with “self” are deleted or inactivated
- binding of the antibodies to the foreign antigens causing neutralisation, opsonisation (make a cell more susceptible to phagocytosis) and complement system activation.
- causes the lysis of cell or enhance phagocytosis
- activation of complement system - results in polymorphonuclear cells
Inflammatory response - histamines, phagocytotic cells and fever may all play a role in local inflammations