Cells and Organs of the Immune System I and II Flashcards
describe antigen factors in immunogenicity
- molecular size: generally > 100,000 Da
-
chemical composition:
- greater complexity (heterogeneity) = greater immunogenicity
- generally proteins > carbohydrates > lipids
- susceptibility to processing and presentation
- D-amino acids cannot be processed
-
adjuvant:
- BSA in mice; alum in humans
- generally increase persistence of antigen and innate response (inflammation, stimulation of APC and/or lymphocytes)
describe host factors in immunogenicity
- genotype of host:
- MHC gene products
- B cell receptors
- TCR
- dosage and administration:
- low doses may induce tolerance or fail to stimulate enough lymphocytes
- boosters increase clonal selection
- route: slow reelase is important for immune response:
- subcutaneous > intraperitoneal > intravenous > intragastrical
- oral route induce local mucosal immunity but not systemic immunity
summarize the factors that influence the immunogenicity of proteins
describe the innate arm of the immune system
- molecular and cellular mechanisms preformed and fully active (immediate reaction)
- non-specific
- distinguishes between self and pathogens but not specialized to distinguish small differences in the foreign particles
- components:
- barriers that protect host
- skin, including its usual skin flora
- mucous membrane
- acidity of stomach
- lysozymes in fluids
- phagocytic cells
- antimicrobial peptides (interferons, complement)
- temperature
- barriers that protect host
describe the acquired (adaptive) arm of the immune system
- develops in response to infection
- adapts to recognize, eliminate, and remember pathogens
- highly specific
- takes several day for this arm to become fully functional
- components: cell-mediated immunity and antibody-mediated (humoral) immunity
name the cellular and humoral components of the innate vs adaptive system
summarize the lineage of immune cells from a stem cell
summarize the CD markers on leukocytes
describe the APCs
describe the general activites of macrophages
- to survey tissue compartments and discover microbes, particulate matter and dead or injured cells
- to inget and eliminate these materials
- to extract immunogenic information from foreign matter
describe neutrophils (granulocyte)
- multi-lobed nucleus: 2-5 lobes
- different granules
-
1st to arrive at site of inflammation
- high #’s is 1st indication of infection
- destroy organisms by:
- phagocytosis
- release of hydrolytic enzymes
- neutrophiles are very short lived (10 hrs in blood, 1-3 days in tissue)
- come out of blood vessels ready to kill, would cause too much damage to tissues if long lived
describe eosinophils (granulocyte)
- bilobed nucleus
- located mainly in tissue
- small central Golgi apparatus, and limited ER and mt
- phagocytize
- specific granules and azurophilic granules
-
specific granules (crystalloid):
- inside: basic proteins, cationic protein, neurotoxin
- outside: histaminase, peroxidase, cathepsin
- functions:
- play a role in elimination of parasitic helminths and allergic reactions
- phagocytize antigen-antibody complexes
describe basophils (granulocyte)
- bilobed, S-shaped nucleus
- granules:
- basophilic specific granules:
- heparin, histamine, chemotactic factors, peroxidase
- basophilic specific granules:
- survive long periods of time (2 years in mice)
- non-phagocytic
- functions:
- play a role in allergic reactions
describe mast cells (and 2 ways to activate them)
- similar to basophils
- play important role in development of allergies
- two pathways for activation:
- innate TLRs
- antibody-dependent (IgE)
describe the function of the 3 classes of lymphocytes (T cells, B cells and NK cells)
- T cells are involved in cell-mediated immunity (cellular immunity)
- B cells are antibody-mediated immunity (humoral immunity) because antibodies circulate widely in body fluids
- NK cells perform immune surveillance, attacking foreign cells, body cells infected with viruses and cancer cells