immune system Flashcards
what is innate (non-specific) immune system?
-first line of defence
-responses are rapid but limited
use toll-like receptors
does the innate immune system involve the production of antibodies?
no
what cells does the innate immune response include?
- neutrophils
- macrophages
- basophiles
- natural killer cells
what is the adaptive or specific immune system?
- specifically targets foreign material to which body has already been exposed
- takes time to prepare for attack
- involves antibodies
- formation of memory cells
what is the response of the adaptive immune system mediated by?
-response is mediated by B and T lymphocytes
what cells are in the adaptive immune system?
T cells
B cells
plasma cells
what are the chemical/internal innate barriers?
- neutrophils
- eosinophils
- basophils
- monocytes
- lymphocytes
what are neutrophils
highly mobile phagocytes that engulf and destroy unwanted material
what are eosinophils
- secrete chemicals that fight parasites
- involved in allergic reactions
what are basophils
- release histamine and heparin
- involved in allergic reactions
what are monocytes
-transformed into macrophages
what are lymphocytes
1) B cells
- transformed into plasma cells that secrete antibodies
2) T cells
- responsible for cell-mediated immunity
- directly destroy and invade mutant cells
what is the complement system?
its a system that compliments the actions of antibodies to kill foreign cells by forming membrane attack complexes (MAC)
how does the compliment system work/ consist of?
consist of plasma proteins, when activated, the donut shaped protein complex embeds itself in the surface membrane of nearby microorganisms , creating a large channel through the membrane- the hole punching technique makes the membrane makes the membrane leaky, resulting in the victim cell swelling and bursting.
what does interferon act as?
a whistle blower
how does interferon work?
When a virus invades a cell, in response to being exposed to nucleic acid, the cell secretes interferon. Once released into the EFC, interferon binds with receptors on the plasma membrane of a healthy neighboring cell as a signal that they need to prepare for a viral attack Interferon is a whistle blower.
what does interferon trigger?
Interferon triggers the production of virus-blocking enzymes. Shen interferon binds with other cells, they synthesis enzymes that can break down RNA and inhibit protein synthesis
what other actions can interferon do?
-enhances macrophage activity and antibody production
-exerts anticancer (NK cells) and T cells
-slows cell division
enhances action of NK cells,
what is inflammation?
-non specific response to tissue injury with the help of a macrophages and neutrophils
are NK cells specific or non specific?
non- specific
-they lyse and destroy virally infection host cells and cancerous cells
what is the sequence of inflammation
-defense of resident tissue macrophages
-localized vasodilation
-increased capillary permeability
-localized oedema
-walling off the inflamed area
-emigration of leukocytes
leukocyte proliferation
-marking of destruction of bacteria
-mediation of inflammatory response by phagocyte-secreting chemicals
-tissue healing and repair
what occurs In localized vasodilation
- bacteria invasion at injury
- release of histamine
- enhances dilation of blood vessles, so more blood flow can go to injured site
- brings more leucocytes and plasma proteins
what is localized oedema?
- the accumulation of plasma proteins in internstial fluid
- moves fluid out of capillary and accumulate in injured area
- causes swelling
- pain from inflammation is causes by distention of swollen tissue and prostaglandins
what occurs in the walling off the inflamed area?
-leaked plasma proteins also brings thromboplastin- thrombin
-this converts fibrinogen into fibrin
-forms a clot around the bacterial invader and damaged tissue
walling off prevents spread of invaders
