chapter 9 Flashcards
epithelial barriers
skin and mucous membrane
- first line of defense
skin epithelium barrier
produces antibicrobial peptides that kill a variety of bacteria and fungi
interstinal epithelium defense
bacterial peptide called cryptocidins: prevents bacteria rom colonizing intestinal wall.
mononuclear phagocyte system
dendritic cells
monocytes
macrophages
-specialize in capturing and presenting antigens to helper T cells
Major Histocomaptability complex
MCH I: identifies host of cell “chelsey”
- presents to cytotoxic T cells.
MCH II: presents antigens of phagocyzed cells to helper T cells.
Primary lymphoid organs
bone marrow: B cells mature
thymus: T cells mature
secondary lymphoid organs
lymph nodes/vessels
spleen
tonsils
peyer patches in intestine
Mature lymphocytes remain
in circulation in lymphatic tissues and blood stream
B lymphocytes
able to produce antibodies
have antibody like receptors: BCR’s
mature into: plasma cells and memory cells
memory B cells
forma reserve of cells that can quickly mount immune response on secondary exposure.
antigen epitope
specific sequence B cells recognize for an antigen.
Base of antibody
constant base region, identifies type of antibody
- IgG
- IgM
- IgA
arms of antibody
variable arms
- reading sequence for antigens
IgA antibodies
in the respiratory and GI tracts
IgM
shaped like a cluster of 5 antibodies
- increased change to recognize antigen
- first antibodies in immune response
Resting T cell
before activation
- activation occurs by reading specific sequence from antigen presenting cell (MHC I)
lymphokines
type of cytokine that communicates with lumphocytes
monokines
type of cytokine that communicates with monocytes
Natural Kill cell
falls under agranulocyte group, but has granulocytes.
can kill cancer and virally infected cells without previous exposure.
- lack of self- identifier (MHC I) triggers target for NK Cells
macrophages live
in specific tissues: named for those tissues
microglial cells
macrophage in the brain
alveolar macrophages
lung
kupffer cells
macrophage in the liver
mesangial phagocytes
macrophage in the kidney
lymph node
resident and recirculating macrophages
monocytes
phagocytic cells/macrophages in blood
synovial A cells
macrophages in the joint
classical complements activation
IgG or IgM antibody-antigen complexes
alternative complement activation
activated on 1st exposure, innate immune response
- triggers: lipopolysaccharides (bacteria) and bacterial endotoxin
lectin complement activation
biomolecule that binds mannose on bacteria cell wall, triggering complement cascade
Complement cascade causes
increased inflammation
chemotaxis
lysis of target cell
clonal diversity
B and T cells can reproduce replicas with different reading sequence identifiers
- antigen reading sequence
immunocompent
elicit immune response
clonal selection
increases of decreases with T and B cells proliferate in accordance with needed immune response
T regulatory cell
regulates (stops) proliferation once immune response is achieved: antigen cleared.
APC
antigen presenting cell
- macrophages
- dendrites
CD8+
cytotoxic T cell: works with MCH I
CD4+
helper T cell: works with MCH II
B cell activation
needs helper T cell to activate proliferation into memory and plasma cells
cell mediated immunity
T cells
T cell receptor recognized foreign antigen
- only able to respond to one antigenic epitope
central tolerance
in thymus where T- cells mature, must go through selection
- negative: T cell recognizes “self” as foreign, destroyed in thymus.
- positive: ensure T cell does not recognize “self” as foreign, as well as does not elicit too harsh immune response.
T helper cell
recognize MHC II activation of kinases in cytoplasm: - activate immune system - neutrophil recruitment - pro-inflammatory signals
cytotoxic T cells
recognize MHCI
proliferate into memory cells and effector cells
humoral immunity
B cells
- binding of antigen to BCR initiates cascade
- - proliferation and differentiation.
— memory b cells and plasma cells
for effective activation B cell must engulf antigen ad present to helper T cell.
Antibody precipitation function
each arm of immunoglobulin Y binds an antigenic epitope
- bind into large insoluble complex
- leave in body fluids
agglutination antibody function
binds to create large complex
- phagocytic cells find large complex
neutralization antibody function
neutralizes bacterial toxin
- binds to toxin before it can interact with cells
- covers active portion of toxin: inactivates
opsonization antibody function
coats foreign antigen making it more recognizable to phagocytic cells.
innate humoral
myeloid cells
innate cell mediated
NK cells
adaptive humoral
B cells: plasma cells
antibodies
Helper T cells
antigen presenting cells
adaptive cell mediated
cytotoxic T Cells
Passive immunity
antibodies donated form immune individual to an unprotected or non-immune individual
- placenta
- breast milk
- serotherapy
active immunity
active infection
vaccination
