immune system Flashcards
what is the primary function of the immune response ?
to find and destroy invading infectious agents and reduce to a minimum the damage they cause.
what does an immune response involve?
Recognising the invader and mounting a reaction against it to eliminate it
what are infectous agents ?
viruses and bacteria. worms, fleas, lice and ticks
where do viruses and many bacteria and protozoa replicate?
inside cells
what diseases are caused by extracellular bacteria, parasites and fungi?
pneumonia
tetanus
sleeping sickness
what diseases are caused by intracellular bacteria and parasites?
leprosy
leishmaniasis
malaria
what diseases are caused by viruses
smallpox
flu
chickenpox
what diseases are caused by parasitic worms?
ascariasis
schistosomiasis
external defense
most important
first line of defense.
skin impenetrable barrier to pathogens
very tight gap junction between cells
microbiome
Inflammatory response
increased blood supply to the infected area.
increased permeability of capillaries- allowing escape of larger molecules and cells.
migration of leukocytes out of venules into surrounding tissues.
leukocytes
mostly neutrophils but later monocytes and lymphocytes
innate immunity
native immunity. In place before infection occurs. Rapid response. Physical barriers, cellular and soluble. Non specific and no memory
innate immunity- cells
myeloid line
cells are phagocytes
polymorhonuclear granulocytes
innate immunity- soluble factors
proteins and peptides
completent 30 proteins
lytic, opsonins,chemotactic
interferons
protect cells against invasion by viruses
opsonin
a macromolecules that becomes attached to the surface of a microbe and can be recognised by surface receptors of neutrophils and macrophages and increases the efficiency of phagocytosis
opsonisation
the process of attaching opsonins such as igg or complement fragments to microbial surfaces to target the microbes for phagocytosis
APC
antigen presenting cells
Adaptive immune response
very specific response with memory
triggered by antigen presentation
what do myeloid cells give rise to?
Myeloid cells give rise to red blood cells, granulocytes, monocytes and platelets
what do lymphoid cells give rise to?
lymphocytes and natural killer cells
HR
an antibody mediated response that occurs when foreign material antigens are detected in the body
antigen
a molecule that reacts with preformed antibody at the specific receptors on T and B cells. most are proteins
epitope
the portion of the antigen which combines with the antibdoy
antibody
a molecules produced by animals in response to antigen
antibody antigen complex
particular property of combining specifically with the antigen that induced its formation
what does the T helper cells do?
organises both cellular and humoural response
T cells
thymus derived.
T helper cells (master of adaptive response)
T cytolytic
B cells
Produced in bone marrow
mature in bone marrow
produce humoural response
memory cells survive a long time
apoptosis
programmed cell death
who invented the vaccine?
edward jenner
epidemic
sudden increase in prevalence
prevalence
% of population infected
pandemic
epidemic occurring over a very wide area, crossing international boundaries
endemic
the constant presence of a disease within a specified geographical area, low prevalence
hyperendemic
constant disease but at very high prevalence and in all age groups
novel pathogen
pathogen entering a population which has no herd-immunity to that specific pathogen
lethality
refers to mortality rather than morbidity
infection fatality rate
percent of infected cases that die
zoonosis
micro or macro parasite transmissible between vertebrate animal to man
