Immunology Flashcards
characteristics of lymphatic vessels
open ended
1 cell thick
flow reliant on pumps and valves
2 primary functions
1) maintain fluid balance
2) active role in immunity
problem with vessels
often results in oedema and being immunocompromised
composed of
lymph, nodes, lymphatic tissues
what are lacteals
specialised lymphatic groups located in the intestinal wall
lymph
mainly plasma water
- lower percentage dissolved proteins (albumin) than plasma
- higher protein in thoracic duct (from liver and SI)
tonsils
palatine, pharyngeal, lingual
1st line defence
contains T/B cells
thymus gland
regresses with age
- source of lymphocytes before birth
responsible for maturation of T cells
Spleen
defence→prod macrophages
- haemotopoiesis (RBC prod) and erythropoiesis (WBC prod)
- blood reservoir - stores platelets & prod RBC
lymph nodes
- lymph filtered through nodes
- defence → mechanical (trap pathogens) and biological (phagocytosis)
- haematopoiesis
innate immunity
1st line: external mechanical/chemical
2nd line: internal: phagocytes, macrophages, WBC…
acquired immunity
3rd line
- natural/artificial
active→T/B cells
passive→AB prod outside body (transfer from mom to child)
Req 2 activating signals: specific antigens and chemicals
immediate vascular effects of inflammation
1) vessels constrict (decrease blood loss) → then dilate (increase BF to start healing)
2) blood becomes thicker
3) endothelial cells contract → increase permeability → release chemical mediators
4) leukocytes attracted via:
a) margination/pavementing
b) diapedesis (movement of WBC to surrounding tissues)
c) chemotaxis
granulocytes
1) neutrophil (1st line of response to insult)
2) eosinophils (active only in parasitic infections→too large to engulf)
3) basophils (secrete chemotatic factors for neutrophils - more involved in allergic reactions)
NK cells
larger granular lymphocytes