Ch.2 Immunological Diseases Flashcards
- Developmental failure of the third and fourth pharyngeal pouches (22q11 microdeletion)
- Presents with T-cell deficeny (no thymus), hypocalcemia (no parathyroids), and abnormalies of heart , great vessles, and fase
Digeorge Syndrome
Primary immunodeficency b/c missing thymus!
Defective cell mediated and humoral immunity= no adaptive immunity
1. Cytokiene defects (bad signling for proliferiton & maturation of B & T cells)
2. ADA definceny; build up of things toxic to lymphocytes
3. MHC Class 2 defincency (no acitvation of CD4+ t-helper cell & cytokiene production)
Severe combined immunodeficiency (SCID)
Factors characterize what disease?
- Susceptibility to fungal, viral bacterial and protozoan infections, as well as live vaccines
- Treatment is** sterile isolation** + stem cell transplant
SCID
What disease?
Complete lack of immunoglobulins due to disordered B cell maturation.
No humoral immunity (no Ig____) Only Cell mediated (t-cell arm)*
due to mutate Burton tyrosine kinase
X linked Agammaglobulinnemia
What disease presents with:
After six months of life with recurrent bacterial, enterovirus (polio & coxsackievirus), and Giardia Lamblia infection
6 months post birth cause thats when IgG from placenta are gone
Live vaccines (polio) must be avoided
X linked Agammaglobulinnemia
- **Low immunoglobulin **due to B cell or helper T cell defects
- Increased risk for bacterial, enterovirus (polio & coxsackievirus), and Giardia Lamblia infection (late childhood)
- increased risk for autoimmune disease and lymphoma
Common variable immunodeficiency (CVID)
- Low serum and mucosal** IgA** (most common immunodefincey)
- Increased risk for mucosal infection; especially viral, however, most patients are asymptomat
IgA defeciency
** Characterized by elevated IgM levels **
* due to *mutated CD40L on helper T or CD40 receptor *
* Second signal follwing antigen presentaion can be delivered to helper t cells = no activation
* **Cytokienes **for Ig- class switchin **not produced **
* Results in low IgA, IgG, and IgE= **recurent pyogenic infection, esp in mucosal sites **
Hyper IgM Syndrome
- Characterized by** thrombocytopenia (**low platlets= no blood clot) , eczema, and recurrent infection.
- **Bleeding **is major cause of death
- due to mutation in **WASP gene (x-linked) **
Wiskott-Aldrich Syndrome
- C5-C9 deficency increased risk for Neisseria infection (N Gonorrhoea and N meningitidis)
- CI inhibitor defficney= hereditary** angiodema,** edema of skin and mucosal surfaces
Complement defincencies
Characterized by immune mediated damage of self tissues
* 1-2% of US population has
Basic mechanism= **intolerance to self proteins, reaction to self **
Autoimmune disorders
Self reactive lymphocytes are regularly generated, but develop ___ or ____
Central (thymus or bone marrow) or peripheral tolerence
Apoptosis!
Central tolerance in the thymus leads to ____ apoptosis are generation of what?
T-cell apoptosis or Regulatory T cells
Central tolerance in the bone marrow leads to __ or __
Receptor editing or B-cell apoptosis
Peripheral tolerance leads to ___ or ___ of T and B cells
anergy or apoptosis
____ Pathway mutations result in autoimmune lymphoproliferative syndrome (ALPS)
Fas Apoptosis
Supress autoimmunity by blocking T-cell activation and producing anti-inflamatory cytokiens (IL-10 and TGF-Beta)
Regulatory T-Cells
CD25 polymorphisms are ssociated with ___
Autoimmunity
FOXP3 mutations lead to ___ syndrome
IPEX syndrome
Autoimmune diseases are more common in what demographic
Woman in childbearing age, hypoestrogen may reduce apotosis self reacting B-cells
T-cells are activated in a T-cell receptor indepened and cytokiene dependent manner
Bystander acitvation
escaped permits
Comon course of autoimmune disorders
Relaspe Remission cycle
APC coming with antigen, presenting to CD4 Cells, interacts, Self-Activation of CD8 & CD4 Cells
BUT these cells are reactive to self-antigens in the body ex. DNA
GO kill or activate NK cells which go and react to self.
Cytokine IL-15 induced
Bystander effect
- Virus/bacteria carry antigens similar to body self antigen (smart cookie)
- Finds Autoreactive T-cell
- Starts **Response to self antigens **(attacking own body) , self antigens are released from damaged tissues (i.e it is not genetic issue)
- APC present self antigen to autoreactive T cells which are activated and undergo clonal proliferation and more self-tissue damage occurs.
Molecular Mimicry
