immunopathology Flashcards
what is immunogy
Immunology is a biological science that investigates the defensive
mechanisms of multicellular organisms against infection”
what are the four categories of pathogenic microorganism
Viruses, bacteria, fungi, eukaryotic parasites
who and what is the term innate immunity
The work of an immunologist, Professor Ilya Metchnikoff, who reported that pathogenic
microorganisms can be digested by phagocytic cells, or macrophages that are always
present in multicellular organisms introduced the term “innate immunity”
what is adaptive immunity
Dr. Emil von Behring and Dr. Shibasaburo Kitasoto demonstrated that
serum of organisms pre-immunised against diphtheria or tetanus carries a specific
antitoxic activity.This allowed to introduce the term “adaptive immunity”
or immunity against a pathogen developed during a lifetime of an individual organism
what are anti bodies
Protective activity of serum relies on the specific type of proteins, called antibodies
what are antigens
Antibodies are developed in a very specific manner against a variety of foreign
chemical structures that are called antigens
where do immun celll originate from
bone marrow
leukocytes
all cells of our immune system
what is Principles of Innate and Adaptive Immunity
Immune system is a network of effector cells and molecules
that act in a coordinated manner to protect multicellular
organisms from infectious agents and harmful substances
what is the first line of defence
macrophages
where do NK cells originate from
from common lymphoid progenerator
where do macrophage hang out and what is their fct
phagocytosis and activation of bacteriacidal mechanism
2nd fct is antigen presentationProvides a link between the innate immunity and adaptive immunity:
one of the antigen-presenting cells (APCs)
-= in in epithelial cells
what is mast cells
release of granules containing histamine and active agents- attract other immune cells
what are NK cells- natural killer
release lytic granules that kill some virus-infected cells
what are dendric cells
antigen uptake in peripheral sites
2nd: antigen presentation to T cells- helps inititate adaptive immune response
what Provides a major link between the innate immunity and adaptive immunity:
one of the APC’s
deneritic cells!!!!
what cells are part of adaptive immunity
b-cells, t-cells
what are adaptive cells
need to to be activated all have receptors on them but need antigen presenting cells- dendrite cells!!!!
what is the purpose of cytotoxix t cells
eliminate virus infected cells
what are memory t cells
hang around longer so that immune response can be very fast
what are b cells activated
by specific antigen binding- soluble agents
why do b cells need t cells
get activated by it
memory b cells
hang around along time too
what are primary lymphoid organs- in red
thymus, bone marrow
secondary lyphoid organ do what compared to primary
hold the mature lymphocytes, while primary makes them
where are secondary lymphoid system
adenoid, tonsil,lymph nodes, appendix, payers patch in small intestine splee
bacteria trigger macrophages to
release cytokines and chemokines
what does release of cytokines and chemokines do
vasodilation and increae in vascular permeability cause redness heat and swelling
what do neutrophils do
inflammatory cells migrate into tissue releasing infammatory mediators that cause pain???
what happens overal when there is an immune response
Pathogenes that cross epithelial cell barriers are met by the
first line of immune defence: macrophages, followed by neutrophils and eosinphils
Their action, associated with cytokine production and active involvement
of dendritic cells, trigger activation of T cells and eventually, B cells in neighboring
lymph nodes. This allows to involve the adaptive immune response
what is MHCs
Major Histocompatibility Complexes (MHCs)
what happens when t cells et activated by MHC1 dendrites
proliferation and differentiation of t cell to acquire effector function - CYTOTOXIC T cells kills
what does MHC 2 do
dendrite MHC2 activates t cells which activates B cell to acquire effector function-> efficient antibody production
everything other than viral infection use which MHC
MHC 2
What does Fc regions on the antiboy do
effector functions, compliment and cell activateion- constant region
what doe the Fab region on antigen do
the =variable region- antigen binding site- looks like a Y and this is the V part
what are the 5 classes of antibodies
Five classes of antibodies: IgM, IgD, IgG, IgE, IgA
why are there so many classes of antibodies
for a range of different thing to bind to
which is the initial antibody that is triggered
the IgM
what happens with bacterial toxins
neutralization- the antibodies bind to toxin
thenthey get ingested by macrophages
what happens in bacteria in extracellular spacce
opsonization- the antibodies surrond the bacteria and get ingested by macrophages
what happens with bacteria in plasma
they bind to the pathogen and recognized by the complement system and makes hole in membrane and does lysis and ingestion
what is type 1 hypersensitivity
anaphylactic or atropic reaction Predominantly mediated by IgE and mast cells
what causes type 1 hypersensitivity
Hay fever Atopic dermatitis Anaphylactic shock Bronchial Asthma-(vasodilation Edema) (bronchial smooth muscles contraction, mucus production, bronchial constriction)
how does type 1 hypersensitivity happen
after the first exposure mast cells have antibodies one them and when next exposure happens the pollen bind to it degranulates mast cells and causes additional cytokines
and additional cells, including
eosinophils and basophils
what are the symptoms of anaphylactic shock
Anaphylactic shock symptoms:
stridor due to vocal cord spasm, choking due
to laryngeal edema, wheezing and shortness of
breeze due to bronchial spasm and pulmonary edema,
systemic circulatory collapse with fainting caused
by hypotension due to vasodilation
what does vasodilatoin and edema cause
leukotriens- arachidonia acid derivatives
what is type 2hypersensitivity
Predominantly mediated by cytotoxic IgG or IgM,
targeting antigens on cells or tissue components, such as extracellular matrix
what are examples of type 2 hypersensitivity
Hemolytic anemia
(targets red blood cells)
Goodpasture’s syndrome
(targets collagen in kidney
and lungs)
Grave’s disease
(targets thyroid-stimulating
hormone receptor)
Myasthenia gravis
(Targets acetylcholine
receptor on muscle cells)
what is type 3 hypersensitivity
Is mediated by immune complexes between antigens and antibodies
that are trapped in blood vessel walls or various membranes formed by
extracellular matrix proteins
what are examples of type 3 hypersensitivity
Poststreptococal Glomerulonephritis
(targets glomerular basement membrane)
Polyarteritis Nodosa
(targets walls in small and medium size
blood vessels)
Systemic Lupus?- not sure yet
what is type 4 hypersensitivity
Is initiated by macrophages, and relies on cross-activation between macrophages
and T cells. Involves production of memory T cells. Often leads to the formation
of granulomas. Relies on multiple cytokines, including IFN-g.
what are examples of type 4 hypersensitivity
Develops in response to tumour-
tuberculosis- and leprae- associated antigens
Contact dermatatis
(latex gloves, poison ivy)
what is autoimmunity
Results from the failure of autotolerance in the immune system.
Associated with genetic predisposition. More common in women
type 1 diabetes
triggered by T lymphocytes,
invlolves Ab production.
Targets insulin-producing
pancreatic b-cells
what is immunodeficiency
Results from deficiency in B cells, T cells or both or may involve the entire
immune system. All characterized by low lymphocyte counts in blood.
May be congenital (primary) or acquired (secondary)
what is an example of primary immunodeficiency
Sever combined immunodeficiency
(SCID)
- Isolated IgA deficiency,
- DiGeorge syndrome
what is an example of secondary immunodeficiency
Acquired Immunodeficiency Syndrome (AIDS).
AIDS is caused by the HIV RNA retrovirus, which is transmitted with body fluids. HIV acts by targeting helper T cells (CD4+), monocytes and macrophages
what is an example of systemic multiorgan) auto immunity
(Systemic lupus erythematosus, rheumatic fever, rheumatoid arthritis)
what is an example of limited to single organ autoimmunity
Multiple sclerosis(CNS) Hashimoto’s thyroiditis Graves’ disease: (thyroid) Autoimmune hemolytic anemia (blood) Pemphigus vulgaris (skin) Myasthenia gravis: muscle
