Semester 2: L18: Immunology 2 Flashcards
Name 3 immune dysfucntions?
Hypersensitivity
Autoimmunity
Immunodeficiency
what is Hypersensitivity?
Excessive responses
what is Autoimmunity?
Inappropriate responses
what is Immunodeficiency?
Inadequate responses
How many classifications of hypersensitivity are there?
5
what type I hypersensitivity?
Immediate hypersensitivity – allergic reactions
what’s Type II hypersensitivity?
Antibody dependent cytotoxic hypersensitivity
what’s Type III hypersensitivity?
Immune complex mediated hypersensitivity
what’s Type IV hypersensitivity?
cell-mediated delayed hypersensitivity
what are allergens?
antigens that can cause an allergic reactions
allergens generally to those who are not allergic are…
innocuous proteins that do not threaten the body
what cells are involved in allergic reactions?
Mast cells, basophils and eosinophils
what are 2 examples of allergic reactions?
Hay fever
Asthma
what happens when someone has asthma?
- mucosal mast cell captures an antigen
- inflammatory mediators, contract the smooth muscle, this increases mucous secretion, and increases blood vessel permeability
what is chronic asthma?
Chronic inflammation of the airways
what’s linked to chronic asthma?
Th2-cells, eosinophils and neutrophils
what is chronic asthma classified as?
Type IV hypersensitivity
A chronic response to asthma is…..
mediated by cytokines and eosinophil products
what are treatments of Type I Hypersensitivity?
Prevention of exposure
Pharmacological treatments
Prevention of production of IgE antibodies
what are the Pharmacological treatments for Type I Hypersensitivity?
Monoclonal IgE antibodies
Antihistamines
Immunosuppressant drugs
what happens during Type II hypersensitivity?
- IgG and IgM antibodies bind on antigens on the cell surface of own cells
- Results to activation of the complement or effector cells
what type of hypersensitivity does haemolytic disease of the newborn link too?
Type II hypersensitivity
what is Haemolytic disease of the newborn ?
mother is negative, with positive child, red blood cells form baby lead to mother producing anti-RhD antibodies, but these can’t cross placenta.
In a 2nd pregnancy the same thing will happen causing a secondary response that will produce IgG antibodies, which will cover the babies red blood cells, destroying them. the baby will have severe anemia, when born can be fatal.
what is Haemolytic disease of the newborn prevented by?
the mother having the anti-D injections
what does the anti-D injection do to prevent Hemolytic disease of the newborn ?
It will coat baby erythrocytes and the immunological response of the mother will not be activated
what happens during Type III hypersensitivity?
- Small soluble antibody-antigen complexes
- The complexes are deposited in tissues
- Activation of complement
Inflammatory response
what is Type IV hypersensitivity mediated by?
T-cells
How long does delayed-type hypersensitivity take ?
1-3 days after exposure
what are examples of delayed-type hypersensitivity ?
contact dermatitis
Poison ivy
Coeliac disease
Type IV hypersensitivity links too?
Contact dermatitis
what is Contact dermatitis ?
- Small amounts of Nickel pass through the skin and interact with human proteins.
- They are then recognised by DC that transfer to the lymph nodes
- Activated T-cells attack the skin area
what is Autoimmunity?
Failure of self-tolerance
what happens to Autoimmunity?
Antibodies or T-cells attack own cells and tissues
autoimmunity resembles what?
type II, III and IV hypersensitivity reactions
Name a Immune complex disease ?
Systemic Lupus Erythromatosus
what are some T-cell mediated disease ?
Rheumatoid Arthritis
Multiple Sclerosis
what diseases have antibody against cell-surface or matrix antigens ?
Autoimmune haemolytic anaemia
Insulin autoimmune syndrome (Hypoglycaemia)
what is Rheumatoid Arthritis?
Chronic and episodic inflammation of joints
what is the Rheumatoid factor?
auto-antibody specific for the Fc region of human IgG
what causes inflammation when someone has Rheumatoid Arthritis?
Over production of TNF (Tumor Necrosis Factor)
what stem treatments for Rheumatoid Arthritis?
- physiotherapy with anti-inflammatory and immunosuppressive drugs
- Monoclonal anti-TNFα antibodies
what are the two type of Immunodeficiency?
Primary Immunodeficiency Diseases
Secondary Immunodeficiency Diseases
what does Secondary Immunodeficiency Diseases cause?
Malnutrition
Immunosuppressant drugs
Tumours, Traumas
Infectious agents
what’s AIDS stand for?
Acquired Immunodeficiency Syndrome
what’s HIV?
Human Immunodeficiency Virus
what does HIV infect?
T helper (CD4+) cells, macrophages and Dendritic cells
HIV leads to the destruction fo what?
CD4 T-cells
when someone has AIDS/HIV what becomes less effective ?
Both antibody-dependent and cell-mediated immunity become less effective
what’s a treatment for HIV?
Highly Active anti-retroviral therapy
Highly Active anti-retroviral therapy involves and does what?
- Combination Therapy
- reduces the viral load
- slows down disease progression
not done slides
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