Unit 4 Flashcards
What does immunity refer to?
refers to protection against infections
What is innate immunity?
Immunity mediated by mediated by cells and proteins that are always present and poised to fight against microbes, being called into action immediately in response to infection
What is adaptive immunity?
Adaptive immunity is normally silent and responds (or “adapts”) to the presence of infections and microbes by trying to eliminate them
What is hypersensitivity,?
Injurious immune reactions
immune responses may be inad- equately _______ or inappropriately _____ to host tissues, and in such situations, the normally beneficial response is the cause of disease (Immune mediated injury)
Controlled, targeted
What is type 1 Hyper sensitivity?
Immediate allergic reaction to allergens which are usually harmless to others
Type I hypersensitivity is activated via _____ cells and produce _____ antibodies. It also causes mast cells to release ______ in order to aid with the attack
T helper cells TH2, IgE, histamine
During Type 1 hypersensitivity there is an increase in mucus secretion, vasodilation, and ____
bronchoconstriction
This type of inflammation causes itching, pruritis, diarrhea, laryngeal edema, increased mucus production, and vasodilation which lead to edema (hypotension if severe)
Systemic
In type 1 hyper sensitivity the inmediate response usually takes about ____ and subsides within_____ . It deals with vascular and sm. muscle reactions
30 minutes, 60 minutes
Late phase reaction in type 1 sensitivity is usually due to ________ _______ and the onset is typically between ___ And ____
epithelial damage, 2,8
What are type 2 hypersensitivity disorders caused by?
antibodies that bind to fixed tissue or cell surface antigens, promoting phagocytosis and destruc- tion of the coated cells or triggering pathologic inflam- mation in tissues.
What are examples of type 2 disorders?
ABO incompatibility, acute rheumatic fever,
Goodpasture syndrome, Graves’ disease
What are type 3 disorders caused by?
antibodies binding to antigens to form complexes that circulate and deposit in vascular beds and stimulate inflammation, typically as a consequence of complement activation. Tissue injury in these diseases is the result of the inflammation.
What are the two main types of Type 3 related inflammations?
• Systemic: fever, arthritis, vasculitis,
lymphadenopathy, nephritis (proteinuria)
• Local: vessel walls, kidneys, joints
What are examples of Type 3 disorders?
Lupus (SLE), polyarteritis nodosa (PAN), reactive arthritis (Reiter syndrome), serum sickness
Type 4 hypersensitivity disorders are caused by
by immune responses in which T lym- phocytes produce cytokines that induce inflammation and activate neutrophils and macrophages, which are responsible for tissue injury.
In type 4 hypersensitivity, cytokine mediated CD4 + T cells usually progress into ______ and can be caused by ______
chronicity, poison ivy
In type 4, direct cytoxicity can cause the ______ to _______
CD*8+ Cells to attack antigens (viruses, neoplastic cells, and transplants)
Examples of Type 4 disorders are
TB, leprosy
What are autoimmune disorders?
Immune reactions to self antigens which affect 2% to 5% of the population in developed countries, and appear to be increasing in incidence.
What is the mnemonic for hypersensitivities?
ACID
A Allergies Type 1
C Cytotoxic Type 2
I immune complex Type 3
D Delayed Type 4 (T cell mediated)
What is immunologic tolerance?
unresponsiveness to an antigen that is induced by exposure of specific lymphocytes to that antigen
what is Self tolerance ?
refers to a lack of immune responsiveness to ones own tissue antigens
what is Failed self tolerance?
Immune response to ones own tissue antigens AKA self reactive T and B cells
What are the two mechanisms that work in concert to select agains self reactivity and prevent immune reactions against the bodys own antigens?
Central and peripheral tolerance
What is central tolerance?
Mechanism that induces apoptosis in the thymus for T cells and B cells in the bone marrow
What is peripheral tolerance?
Mechanisms which causes functional deactivation, suppression, or apoptosis of T cells which escape the thymus
What tissues are primarily affected by Autoimmune disorders?
Connective tissues and vessels
what is the most common cause for AI disorders?
Idiopathic but can also go with Genetic mutations and environmental factors
Autoimmune diseases have a tendency to run in fami- lies, and there is a greater incidence of the same disease in monozygotic than in dizygotic twins. (True or False)
True
What are the Alleles that are linked with Autoimmune disorders?
HLA
When dealing with genetic susceptibility one would expect ____ _____ to be most commonly affected
Childbearing women
What are the mechanisms through which viruses and bacteria can cause AI reactions?
Cross reactivity and infections with necrosis and inflammation
What is SLE ?
a multisystem auto- immune disease of protean manifestations and variable clinical behavior which has Massive antibody formation due to failed self tolerance
It is extremely variable and may involve any organ but is particular to the skin, kidneys, serous membranes, joints, heart, and CNS
It has an insidious onset
Unpredictable and can relapse
Where is SLE most common?
In young adult females of african american heritage