Traffic - week 12 Flashcards
External Defenses (first line of defense)
Skin (integument)
physical barrier, skin-associated lymphoid tissue (SALT), chemical barrier
Mucous membranes and associated structures (line cavities open to outside of body) (SSSAG - sal)
saliva, stomach acid, secretions/antibodies, GALT, appendix
digestive tract
a. salivary enzymes kill bacteria
b. acid in stomach kills bacteria
c. secretions contain antibodies
d. normal intestinal bacteria outcompete pathogens (disease causing organisms)
e. gut-associated lymphoid tissue (GALT) a.k.a. Peyer’s patches contain immune cells
f. appendix contains immune cells
genitourinary tract (joseph)
a. acidic urine
b. acidic vaginal secretions
c. sticky mucus in genitourinary tract traps pathogens & has antibodies
(1) swept out as organ empties
(2) engulfed by phagocytes
respiratory tract (Kristian)
a. large particles filtered by hairs in nasal passages
b. tonsils and adenoids contain immune cells
c. sticky mucus traps pathogens in airways
(1) cilia sweeps mucus upward (swallowed, or coughing, sneezing or expectorating removes it from body)
(2) antibodies secreted in mucus
d. alveolar (air sac) macrophages engulf pathogens
White blood cells - Defense Cells (NEMBL)
NEMBL
neutrophils, eosinophils, basophils, lymphocytes,
(B and T), monocytes
lymphocytes (and some others) found in lymphoid tissues (LTTSSAAG)
LTTSSAAG
store, produce or process lymphocytes b. lymph nodes, spleen, thymus, tonsils, adenoids, appendix, SALT, GALT
c. located to catch invaders and decrease their spread
Nonspecific defenses (innate immunity)
responses that defend against any invader or abnormal material
- triggered by general molecular patterns associated with pathogens or other dangers
Inflammation - innate (Inflammatory Response) (flamming)
designed to bring phagocytes and plasma proteins to injured area
a. destroy/inactivate invaders
b. clean up debris
c. prepare for healing
neutrophils and monocytes migrate to area - innate - (luke - hall)
a. margination- CAMs on capillary cells cause leukocytes to stick to capillary walls
b. move to tissues by diapedesis
c. leukocytes follow chemical trail to damaged tissue (chemotaxis)
d. phagocytosis occurs to recognized substances (1) rough surfaces of damaged cells
(2) opsonins - chemical placed on non-self cell by
immune system, links it to phagocyte (antibodies, complement)
phagocyte secretions (cytokines) enhance response (joseph ferris)
(1) nitric oxide (toxic to bacteria)
(2) lactoferrin (binds iron so bacteria can’t use it to reproduce)
(3) histamine
(4) clotting triggers
Interferon (Linda tv)
released by virus-infected cells, triggers production of virus-blocking enzymes in nearby cells
2. enhances role of phagocytes and other immune cells on virus-infected and cancer cells
Natural killer cells - innate (lymph cancer)
similar to a type of lymphocyte, lyse
virus-infected cells and cancer cells
Complement system (c’s wake up- kin)
exposure to pathogen, MAC serve as chemotaxins and opsonins, vasodilation and histamine release d. activate kinins
plasma protein precursors activated by exposure to pathogen or antibodies
a. lyses non-self cells
(1) membrane attack complex (MAC) inserts into bacterial membrane and pokes holes b. serve as chemotaxins and opsonins
c. promote vasodilation and histamine release d. activate kinins
Specific Immune Responses (adaptive immunity) (growing bee corner)
act on particular invaders
B and T lymphocytes
during maturation each B and T cell becomes capable of responding to a particular invader (only one specific kind of invader for each individual cell)
a. which invaders we can respond to is genetically determined
adaptive - recognize antigens (large)
large, complex molecule that the immune system can respond to
a. usually proteins, or large polysaccharides
b. maybe on cell surface or individual molecules secreted by the pathogen
self-antigens are plasma membrane glycoproteins - adaptive (prof piano)
major histocompatibility complex (MHC) is a group of genes that determines which MHC glycoproteins an individual has
b. lymphocytes do not harm these cells under normal conditions
antibody mediated immunity (bee a mediator)
B cells display antibodies on their surfaces and secrete them
a. antibodies are also called gamma globulins or immunoglobulins (Ig)
b. each antibody molecule has 2binding sites for a specific antigen
When a B cell clone is exposed..(antibody mediated immunity)
to the right antigen the cells reproduce and…
a. some become plasma cells, which secrete
antibodies
b. some become memory cells, which launch a more powerful attack if the body is exposed to that antigen again (secondary response)
antibodies enhance immune responses (ant stove)
neutralization- bind to free floating antigens and stop them from causing harm
b. most powerful activator of complement system (so enhance inflammation)
active immunity occurs when (bee activity)
an individual’s B cells make antibodies
a. infections, vaccines
passive immunity is when (donor)
antibodies come from a donor who is immune
a. breast milk, snake bite/rabies/tetanus shots
Cell-mediated immunity (mac in cell - mediator)
macrophages “present antigen” to T cells (often to B cells also)
- macrophage phagocytizes antigen and places it on its surface
- appropriate type of T cell binds and is activated to reproduce and differentiate
- T cells require both non-self and self antigen to bind and destroy a cell
types of T cells (ramirez kitchen door)
cytotoxic T cells (killer cells or CD8 cells)
a. destroy virus-infected, cancer or transplanted cells (1) direct killing by releasing perforin to poke holes
and lyse cell
(2) indirect by signaling for apoptosis
(programmed cell death)
helper T cells (CD4) (help w/ tp in hall) (ADAPTIVE)
secrete cytokines that regulate nearly all aspects of immune response, including…
(1) B cell growth factor
(2) T cell growth factor (interleukin 2)
(3) chemotaxins
(4) macrophage-migration inhibiting factor keeps macrophages in area and makes them more powerful
suppressor T cells
do not need presented antigen to be active b. limit responses of other immune cells
c. reproduce more slowly than other immune cells and shut down immune responses after they’ve served their purpose
Cells that blur the boundaries of innate (general defenses) and adaptive (lymphocytes) immunity (blurry desk)
innate lymphoid cells (ILCs) similar duties as T cells but faster and less powerful
2. innate response activator cells (IRA) B cells recognize bacteria and produce cytokines to activate other innate cells (not typical of B cells)
physical barrier (1st line) (kera)
keratinocytes form barrier, also influence immune cells
skin-associated lymphoid tissue (SALT) (1st line) (s-special)
contain specialized immune cells
chemical barrier (1st line)
secretions of sweat and oil (sebaceous) glands are toxic to bacteria
neutrophils (defense cells) (phil)
highly mobile phagocytes
eosinophils (defense cells) (ear)
secrete chemicals that kill parasitic worms, involved in allergic reactions
basophils (defense cells) (basal sneeze)
release histamine and heparin (inflammatory response) involved in allergic reactions
lymphocytes (defense cells) (lymph front door)
can reproduce outside bone marrow (in lymphoid tissues like lymph nodes). B and T lymphocytes
monocytes (defense cells) (monica tv)
become macrophages - large phagocytes in tissues
- most in tissues, some circulate in blood
inflammation characterized by (arm)
d. characteristics include redness, heat, swelling and pain
resident macrophages begin phagocytosis
resident macrophages begin phagocytosis - innate - (inflammation) (sf state sailing)
- histamine released from mast cells (similar to basophils, present in connective tissues) causes…
a. vasodilation➝increased blood flow (redness,heat)
b. increased capillary permeability➝plasma proteins flow out ➝ edema (swelling, pain) - “walling off”of area due to fibrin forming interstitial fluid clots (inhibits spread of invader
after clotting (kin) in phagocyte secretions
(5) enzymes that trigger kinin production
(6) endogenous pyrogen (EP) which causes fever and encourages inflammatory response
(7) interleukin 1 (IL-1) enhances lymphocyte
production
B lymphocytes specialize in (adaptive) (bee 60s micro)
recognizing free- existing invaders like bacteria, bacterial toxins, some viruses (antibody-mediated or humoral immunity)
T lymphocytes specialize (adaptive) (chemo)
killing virus-infected and cancer cells (cell-mediated immunity)
antibodies enhance immune response by acting as (opal basket)
c. opsonins, enhancing phagocytosis
d. cause agglutination (clumping) of cells with antigen
e. stimulate killer cells to lyse bacteria (similar to natural killer cells but require antibodies)
B lymphocytes (micro)
secrete antibodies. probably mature in bone marrow
T lymphocytes (killer)
destroy virus infected and cancer cells. mature in thymus
lactoferrin
binds iron so bacteria can’t use it to reproduce
kinins (kin)
stimulate complement, reinforce histamine effects, activate pain receptors, act as chemotaxins
adaptive is only..
T and B lymphocytes
antibody mediated immunity is only..
B cells
the innate cells are…..
macrophages, neutrophils, eosinophils, basophils, mast cells, natural killer cells, and dendritic cells.
the adaptive cells are..
B cells (or B lymphocytes) and a variety of T cells (or T lymphocytes), including helper T cells and suppressor T cells.
primarily involved in cell-mediated immunity
T lymphocytes
T cells do not have antigen “presented” by
complement
B cells make antibodies, the functions of which include
acting as opsonins
