Dealing with disease Flashcards
Pathogen and antigen
Pathogen- agent that causes disease
antigen- molecule that triggers immune response
Self antigens
- on cell surface
- immune system don’t attack them
-MHC class I and MHC class II markers - class II is on specialised cells of immune system
class I is on all cells with a nucleus
Non-self antigen
- ‘foreign’
- attacked by immune cells
Cellular pathogen, non-cellular pathogens + examples
Cellular- living with cellular structure, e.g. bacteria, fungi, protozoa
Non-cellular- Non-living, don’t have cellular structure, e.g. viruses, prions
1st line of defence
- innate/non-specific
- physical and chemical barriers
2nd line of defence
Innate, non specific and immediate response
Leukocytes and phagocytes
Leukocyte- White blood cell
Phagocytes- leukocytes that destroy pathogens and foreign material via enodcytosis
Neutrophil and cytokine
Neutrophil- Phagocytes pathogens and foreign material. Also releases cytokines
Cytokines- signalling molecule. aids in communication between immune cells.
NK cells
Recognises and destroys damaged or infected cells
Mast cells
Contains histamine which can be released to help in immune response
Eosinophils
Contains toxic chemicals to destroy pathogens
Targets pathogens that are too large to be phagocytosed
Interferon
- Non cellular
- interacts with neighbouring cells so that they’re less susceptible to infection
Macrophage and dendritic cells
Phagocytoses pathogens and present them on their MHC Class II markers
Complement proteins
Reacts with each other to create a complement cascade to destroy pathogens
Cytotoxic T cells
attack pathogen-infected and cancer cells by inducing apoptosis
