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35 Cards in this Set
- Front
- Back
When was an immmunodeficiency first described?
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as early as 500 b.c.
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T/F immunology as science is a new discipline.
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true, b/c of HIV that we started to learn about immune system.
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What are the 2 types of immunodeficiences?
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Primary/congenital
Secondary/acquired |
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What is described as primary/congenital immunodeficiency?
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are genetic defects that result in an increased susceptibility to infection
- is frequently manifested in infancy or childhood (because at beginning have mother's ab) - such diseases affect about 1 in 500 people in the US |
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What is describe as secondary/acquried immuno.
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develop as a consequence of - malnutrition, disseminated cancer, treatment with immunosuppressive drugs, or infection of cells of the immune system.
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INtegrity of the immune system is essential for defnese againt infectious organisms and their toxic products
that being said, is the immuen sytem impt. for our survival? |
yes!
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T/F Toll-like receptors are highly conserved across widely diverse species
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true, any loss of function mutation affecting a TLR has negative consequences for survival
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What are TLR?
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on immune cells like centinals (macrophages and leukocytes)
- part of innate immune system |
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Can you survive without an innate immune system?
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no
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Can you survive with damage in adaptive immune system?
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yes
- affect primary adaptive immune system and thus affect adaptive |
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Where can the system be 'damaged' in primary immunodeficiencies
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affect primarily one or more components of the immune system, including T/B cells and NK cells as well as phagocytic cells and complement proteins
- or may result from defects in Leukocyte matureation or activation for from defect in effector mechanisms or innate and adaptive immunity. - so pretty much everything can be affects = problem in presence of ag |
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What is the principal consequence of an immunodeficiency ?
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an increased susceptibilty to infection:
the nature of the infection in a particular pt. depends largely on the component of the immune system that is defective. in other words: the types f recurring infections can predict the type of immunodeficiency - pyogenic - humoral viral - cell-mediated |
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X-linked agammaglobulinemia - XLA - does this effect men or women more commonly?
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MEN, because it is x-linked.
all ab isotypes are very low - not even IgM or IgD - circulating B cells are usually absent - Pre-B cells are present in reduced numbers in the bone marrow - no germinal centers in LN so they are small (because no B cells) - Thymus architecture is normal, as are the T cell-dependent areas of spleen and LNs |
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What is the defect in Bruton's Agammaglobulinemia?
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with a loss of function of Bruton Tyrosin Kinase that is impt. for pre-B cell expansion and maturation into Ig-expressing B cells.
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What type of Immunodeficiency and what system (humoral or cell-mediated) is Bruton's Agammaglobuloinemia?
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Humoral - primary deficiency
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What is X-linked immunod. with hyper IgM?
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can only make IgM in high quantities
-very low serum IgG, IgA, and IgE like boys with XLA, pts. with hyper -IgM may become symptomatic during the first or second year of life with recurrent pyogenic infections (humoral) - otitis media, sinusitis, pneumonia, and tonsillitis |
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*What is the diff. between hyper-IgM and XLA?
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*pts. with XLA, don't have lymphoid hyperplasia and hyper-IgM do have hyperplasia
have very large and palpaple LN |
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What is the defect of hyper IgM?
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Occurs during isotype switching - typically with B cell, in the beginning have igM on their surface, once they recognize ag, they go through isotype switching and secret ab for the same ag. - cells susceptible to this can't DO this! Can't express CD40 ligand (critical coactviation molecule for B cells) thus, loss of this molecule prevents the T cell from co-stim ag-specific B cells (through CD40)
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SO, what does the problem with T cell's not expressing CD40 ligand have to do with B cell isotype switching?
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B cells are not signaled by the T cell to go through isotype switching and only produce IgM
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Deficient _________immunity usually results in increased susceptibility to infection by pyogenic bacteria
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humoral
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What is the treatment for deficiency in humoral immunity?
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pretty routine - prophylactic ab and/or gamma globulin therapy
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Deficient ----------- immunity usually results in increased susceptiblilty to viruses and other intracellular pathogens.
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cell-mediated
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T/F Cell mediated immunity is a little bit "rougher' or more dangerous for the indiv.
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true, b/c harder to treat, and infections more serious
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T/F It is rare that pts. with absolute defects in T-cell function survive beyond infancy or childhood.
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true
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DiGeorge's Syndrome - is what?
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developmentally-related disease
thymus does not develop ind. with this problem can't mature T cells b/c no where to go after leave bone marrow. Relative increase in B cell function |
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B cell increased numbers in ind. with DiGeorge's syndrome still have impaired B cell function, why?
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Because B cells need T Cells to work.
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A more common X-linked Recessive Severe Combined immunodeficiency Disease - in pop culture, what is this referred to as? why?
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the bubble boy
- X-linked SCID (XSCID) growth appears normal initially, but extreme wasting usually develops after infections and diarrhea begin - persistent infections with opportunisitc organisms - these infants also lack the ability to reject foreign tissu and are therefore at risk for GVHD (graft vs. host disease) - XSCID pts. have few or no T cellls and NK cells - Pts with XSCID usually have elevated percentages of B cells - but these B cells dont' produce immunoglobulin normally normally, even after T-cell reconstitution by bone marrow transplantation |
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How do you treat Immunodeficiences?
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Bone marrow transplant - main treatment of choice (XSCID)
passive immunization Current treatments of immunodeficience have two aims: 1 - to minimize and control infections 2 - replace the defective or absent components of the immune system by adoptive transfer and/or transplantation |
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What is an example of secondary/acquired immunodeficiency disease?
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most commonly recognized: HIV
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What is HIV, how does it work?
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attaches itself to CD4+ receptors on the T cell primarily and to chemokine receptors
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What are the most common reservoirs of HIV?
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CD4+ T cells - primarily infected and release most in blood stream
- macrophages/monocytes - resting/memory CD4+ cells All = plasma Virus |
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What is the progression of the HIV disease?
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DC if and when they pick up HIV - they can then carry it to the LN and this is where the majority of your B and T cells live and they are then recruited and infection is established. = spread via viremia
- have some control via cytotoxic lymphocytes - so they will be killing infected T cells |
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So, during the progression what two things are seen?
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Thus 2 things occur:
1. clinical latency - viral cessation (can be trapped in DC and wait for ) 2. full AID response - destruction of the lymphoid tissue. |
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T/F Patients can live longer no than they used to with treatment?
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yes, see the symptoms much later in life leading to death (years later)
- don't know why it become active again...have inc. loss of T cells and dec. effect of fighting infection |
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SO, what DOES kill the HIV pt?
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opportunistic infection and diseases because of lack of immune system.
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