immunity pt 2 Flashcards
cell mediated immunity
T-lymphocytes - start in pone marrow, mature in thymus
activated with Ag –> sensitized T cell
activated T cell roles
production of lympohkines cytotoxic T cells T helper cells T suppressor cells T memory cells
CD4 T - cells
75% of all T cells
secrete lymphkines
lymphokines - MIF
migration inhibitory factor
inhibits microphages from leaving
lymphokines - MCF
macrophage chemotactic factor
attracts macrophages to site of Ag
lymphokines - BF
blastogenic factor
induces proliferation of more specific T cells and B cells
lymphokines - interferon
antiviral agent
interferes w/ viral replication
suppressor or regulator T cells
suppress activation of the immune system and prevent pathological self reactivity or autoimmune diease
cytotoxic T cells (CD8)
helps other T cells recognize and destroy virally infected cells
T memory cells
repsond to second exposure of the same Ag must chaster as a rule
cell mediate immunity involved in
viral infections fungal infections some bacterial infections delayed hypersensititivies graft rejection cancer suveillance
HI review
directly from bone marrow
larger cells
shorter life span (days)
non circulating
CMI review
starts in bone marrow - mature in thymus
small cells
longer life span (weeks)
circulating cells
innate states of immunity
physiological
anatomical
acquired states of immunity
artificial
natural
active
passive
active acquired immunity
protection acquired by introduction of an Ag
intended to last a lifetime BUT some mutate too quickly for vaccine to keep up (flu)
passive acquired immunity - naturally
Ab transplacentally or through colostrum and breast milk
passive acquired immunity - artificially
Ab or sensitized lymphocytes produced by one person are transferred to another
usually short duration - until Ab are degrated
two phases in generation of an immune reponse
primary and secondary
primary response
when Ag is first encountered
slow
weak response allows invader enough time to cause illness
IgM first to be produced
secondary response
the next time the antigen is encountered
quicker and stronger each time
memory B cells recognize antigen and all begin to divide quickly
lots of plasma cells - esp IgG
immune response will end when
the antigen that caused it is no longer present.
aging and immune system
immune fx declines w/ increasing age
changes are observed in both innate and acquired immunity defenses
end result is reduced resistance to pathogens and increased incidence of tumors and autoimmune disorders
iatrogenic
medical disorder caused by diagnosis manner or treatment of a physician
urinary catheters, nasogastric tubes, chest tubes, external fixations devices, implanted prostheses