leucocytes and inflammation Flashcards
What is haematopoeisis?
production of blood cells
What is leucopoeisis?
production of leucocytes
What produces leucocytes?
common leucocyte precursor
What are the two major leucocyte lineages?
lymphoid and myeloid
Describe the lymphoids
small, bland-looking cells
Describe myeloid cells
- larger cells
- most have prominent cytoplasmic granules (granulocytes)
What are the functions of macrophages?
- phagocytosis and activation of bactericidal mechanisms
- antigen presentation
What are the functions of dendritic cells?
- antigen uptake in peripheral sites
- antigen presentation in lymph nodes
What are the functions of neutrophils ?
- phagocytosis and activation of bactericidal mechanisms
What are the functions of eosinophils?
killing of antibody-coated parasites
What are the functions of mast cells?
- release granules containing histamine and othr active agents
What are the type of cells within the lymphoid lineage?
- T cells
- B cells
- Natural killer (NK) cells
What do B cells do?
produce antibodies
What are the two types of t cells?
- CD8 T cells
- CD4 (helper) T cells
What do CD8 T cells do?
important in dealing with intracellular infection (viral infection)
What do CD4 helper T cells do?
needed to direct the activity of the immune system
Describe the development of T cells?
- precursors produced in bone marow
- complete maturation in the thymus during gestation
What do Natural Killer (NK) cells do?
important in dealing with intracellular infection and tumours
What are cytokines?
small proteins released by cells that have an effect on another cell
What are chemokines?
small proteins released by cells
How do chemokines differ from cytokines?
- different protein structure
- different receptors
- involved in temporal and spatial organisation
What are cardinal features for inflammation?
- pain
- heat
- redness
- swelling
- loss of function
What are the main features of systematic inflammation?
- fever, fatigue, muscle pain, anorexia
- with time, loss of muscle and fat
What is systematic inflammation largely caused by?
cytokines released into circulation and their effect on distant tissues
What are the possible outcomes of acute inflammation ?
- resolution (insult removed, tissue heals completely)
- fibrosis (insult removed but tissue scarred)
- chronic (can’t be removed)
- abscess formation
Why is inflammation helpful?
- amplifies immune response
- focuses the immune response
- activates the next stages of immunity (B cells/T cells)
What are some bad things about inflammation?
- may damage healthy tissue
- may be activated inappropriately
- may be activated in an uncontrolled manner (septic shock)
Which cytokines are important in inflammation?
- TNF alpha
- IL-1
- IL-6