U1T2 - Keywords Flashcards
Immunity
Immunity
The action of the body’s immune system + how it deals with infectious diseases.
Antigen
Chemicals capable of producing a specific immune response. Molecule found on surface of living cells. Usually protein, may be nucleic acid/polysaccharide/inorganic molecule. All living cells have them. Self or non-self.
B Lymphocyte
If B cell receptors/genes stimulated, begins antibody mediated response. Formed from stem cells in bone marrow, mature in bone marrow, antibody mediated/humoral immunity. Produce antibodies in response to antigens due to bacterial/viral infection.
T Lymphocyte
If stimulated, begins cell mediated response. Divides into 4 types of T cell. Formed from stem cells in bone marrow, mature in thymus gland, cell mediated immunity. Respond to antigens attached to body cells (viral infection).
Antibody Mediated Response
Where B cell receptors stimulated so produces antibodies into blood stream + other body fluids. AKA humoral response.
Cell Mediated Response
If T cell stimulated by own body cells which have been changed by presence of non self material within them, directly destroys cell infected by pathogen. e.g. macrophages, viruses, cancer.
Antibody
Specifically shaped globular protein molecule, each responsible for dealing with specific pathogen (complementary to antigen).
Agglutination
Cells clumping together. 1st stage in allowing efficient phagocytosis by polymorphs. Allows engulfment + destruction by lysosomal digestion inside cell.
Clonal Expansion
Where stimulation of B cells results in cell division + production of new cells. e.g. clone plasma cells + clone memory cells.
Memory Cells
Clone cells which are specialised to fight a specific bacteria. Remain in circulation for years/life so secondary infection dealt with more quickly.
Memory T Cells
Circulate in body fluids. Rapid infection response for secondary infection.
Helper T Cells
Stimulates other immune cells (B cells), speeds up phagocytosis + secretes protein interferon to limit cell division.
Suppressor/Regulating T Cells
Stop immune response once invading cells destroys. Prevents autoimmune response.
Killer/Cytotoxic T Cells
Destroys infected cells by attaching to antigen on CSM + uses direct enzyme action.
Passive Immunity
Transfer of antibodies from 1 organism to another. Short term protection as antibodies eventually broken down.
Active Immunity
Own immune system being activated to produce antibodies. Long term immunity due to memory cells produced.
Natural Passive Immunity
Innate Immunity. Natural transfer of antibodies through placental transfer or colostral transfer.
Acquired Passive Immunity
Artificial injection of purified antibody (in serum) from blood of recovering patient/previously vaccinated animal.
Monoclonal Antibodies
Hybridising sensitised B cells from mouse which make required antibody (mouse inoculated with purified antigen) + lab grown cancerous cells. Hybrid cells grown continuously under optimum conditions so continuous antibody supply for medical applications.
Natural Active Immunity
Catching disease + creating memory cells so protected for life.
Artificial Active Immunity
Vaccines. e.g. Edward Jenner + smallpox. Attenuated/dead pathogens, isolated antigens + toxoids. e.g MMR, HPV, TB.
Attenuated
Purposely mutated.
Toxoids
Inactive toxins which still activate immune response.
Primary Immune Response
Triggered by body’s first contact with certain antigen (vaccine/pathogen encounter) No memory cells, slow response. Produce memory cells for future encounters.
Secondary Immune Response
Faster than primary as memory cells can be cloned rapidly (large concs of antibodies produced quickly for B cells) Disease symptoms may not even show as so quick.
Tissue Matching
Before organ donated, screened using HLA system. Determines genetic similarity in genes directly involved in antigen production. Fewer differences between donor + recipient HLA genes, more likely to be successful.
Immunosuppressant Drugs
After donation, recipient given cocktail of drugs to scale down action of immune system. Interfere with DNA replication of T + B cells so reduce number. Allows organ to function without major damage from immune system.
X-ray Irradiation
Radiation from x-rays can be targeted on bone marrow, resulting in recipient producing fewer immune cells (B + T)