Immunology of Autoimmunity Flashcards
when do autoimmune diseases occur
when components of the human immune system become perturbed
- some factors involved in this are known
how do biologics used to treat autoimmune diseases work
- work by interacting and modulating with components of the innate and adaptive immune system
- so autoimmune diseases can be treated by either dampening down these adaptive immune responses (mostly auto reactive B and T cells)
- or innate responses (mostly proinflammatory cytokines) - based on antibodies- work by blocking receptors or binding to and inactivating their ligands
what do many autoimmune diseases manifest as
chronic inflammatory diseases
what are the characteristics of innate immunity
- present at all times
- reacts immediately
- activates the adaptive system
what are the characteristics of adaptive immunity
- develops in response to infection and is protective against specific pathogens
- leverages components of the innate response and develops memory
- both innate and adaptive are required for normal function
what is inflammation
the reaction of vascularised living tissue to local injury
- it is a series of vascular and cellular reactions, aiming to protect the body against the injurious agent
what are the cardinal signs of inflammation
- heat
- redness
- swelling
- pain
- loss of function
what are the types of inflammation
- acute- sudden onset and short duration
- chronic- gradual onset and long duration
give examples of innate immune cells
- neutrophils
- macrophages
- dendritic cells
- natural killer cells
where are monocytes derived
derived from hematopoietic stem cells in bone marrow
- blood= 1-6% leukocyte
what is the function of monocytes
- migrate into tissues and differentiate into macrophages
- they phagocytose microorganisms and present antigens to T cells
what does the name of monocyte derived cells depend on
depends on the tissue they reside in:
1. liver= Kupffer cells
2. lung- alveolar Mf
3. CNS- microglial cells
4. bone- osteoclasts
where are polymorphonuclear neutrophils derived
- 50-70% of circulating white blood cells
- infection activates cytokines that stimulate the bone marrow to produce neutrophils
what is the function of neutrophils
- they are active phagocytic cells
- they circulate in peripheral blood for 7-10 hours and migrate by extravasation into tissues, where they have a lifespan of a few days
- they are attracted to tissues by chemotactic factors
give examples of soluble mediators
cytokines and chemokines
how does the balance and level of cytokines and chemokines secreted affect the outcome of the response
- alert to infection
- recruit cells to site
- activate further immune response
what effect do cytokines have on endothelial cells
change the morphology, adhesive properties and permeability of endothelial cells