immunity Flashcards
what are the 5 host defence mechanisms
Innate immunity Phagocytic mechanisms Acquired immunity Antibody and complement Cell mediated immunity
what is innate immunity
nonspecific defence mechanisms like physical barriers such as skin and phagocytic cells
what are the three types of polymorphs
neutrophils, eosinophils ad basophils
what is opsonisation
bacteria is targeted for destruction by an immune cell known as phagocyte
when do B-lymphocytes differentiate into plasma cells
when they recogise a specific epitope
what do antibodys in innfection do?
neutralises bacterial toxins (e.g. tetanus, diphtheria)
neutralises viruses in viraemic stage
prevents adherence of microorganisms
opsonises capsulate organisms (Strep pneumoniae, Haemophilus influenzae)
useful means of diagnosis (serology)
what is humoral immunity
mostly bacterial infection
extra-cellular
acute inflammation
neutrophilia
what do Th1 cells do
activate macrophages to ingest and kill or contain pathogen
what do monocytes in blood mature into?
tissue macrophages
what are macrophages?
white blood cells that engulf foreign cells
are lymphocytes phagocytic?
no
whats the difference between lymphocytes and phagocytes
lymphocytes generate specific immune responses against pathogens whereas phagocytes generate the same response to any pathogen.
and phagocytes can be macrophages, neutrophils etc
what is phagolysome?
cytoplasmic body formed by the fusion of a phagosome with a lysosome in a process that occurs during phagocytosis.
what is the function of phagolyosome
intracellular destruction of microorganisms and patho
what kind of organisms are resistant to phagocytosis
capsulate organisms for eg, strep pneumoniae
what kind of organisms are resistant to intra-cellular killing?
Mycobacterium tuberculosis
whats the difference between innate and acquired immunity
Adaptive immunity is created in response to exposure to a foreign substance
innate immune system is composed of physical and chemical barriers, phagocytic leukocytes, dendritic cells, natural killer cells, and plasma proteins.
what are the protiens with antibody activity?
immunoglobins (Ig)
what are the 5 classes of immunoglobins?
Primary response (IgM) Secondary response (IgG) Mucosal immunity (IgA) Allergy and helminth infection (IgE)
what does polyclonal antibody mean?
multiple specificty
what antibodys are involved in complement?
IgG or IgM
primary or secondary
what do TH2 cells do?
control B cell antibody response
what are the two types of CD4 cells
Th1 and Th2
