Term
What cells are considered peripheral blood mononuclear cells (PBMCs)? What chemical solution has the same specific gravity as PBMCs? |
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Definition
T cells, B cells, NK cells, monocytes
Ficoll-Hypaque solution (used to separate PBMCs from blood) |
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Term
What is the function of CD3 on TH1 cells? What other surface markers does it upregulate? |
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Definition
Function: acts as signal transduction element of TCR
Upregulates: IL-2 R and CD-40L |
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Term
What is the function of IL-2? What promotes its secretion? What cell secretes it? |
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Definition
Function: promotes Th cell division and clonal expansion
Secreted by: Th cells (therefore, autocrine)
Secreted increased by: B7-CD28 interaction
- B7 (CD80) is found on APC
- CD28 is found on T cell |
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Term
On whose surface is CD40L found? What is its purpose? |
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Definition
Found on surface of Th cells
Purpose: bind CD40 on APC cell --> activate APC |
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Term
What is the purpose of the lymphocyte proliferation assay? |
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Definition
To detect if lymphocytes will react and clonally expand to an antigen. Test for increased radioactivity (from thymidine) |
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Term
What is the progression of the immune response in 8-24 hours? 24-48hrs? 72-120hrs? |
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Definition
8-24hrs: some cytokines and cell surface markers
24-48: more cytokines, DNA synthesis, cell division
72-120: clonal expansion, antibody production, killer cell function |
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Term
What is the purpose of the ELISPOT assay? |
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Definition
Detect number of T cells/B cells that are secreting cytokine/antibody |
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Term
Chromium (51-Cr) is used as a marker to detect what? |
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Definition
CTL-mediated cytotoxicity - how effective they are at killing the target cells marked with Cr. |
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Term
What are some in vivo immune responses where in vitro lymphocyte proliferation assays can be used as a model? |
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Definition
1) Delayed type hypersensitivity (DTH)
- Memory cells after initial exposure to antigen
2) Transplant rejection
- expose recipient's lympoctes with MHCs from donor (mixed lymphocyte response)
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Term
In flow cytometry, what does side scatter measure? forward scatter? |
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Definition
side scatter = complexity (granules)
forward scatter = size |
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Term
What is the purpose of flow cytometry? |
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Definition
To determine the types of markers and receptors on the surface of a cell |
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Term
What do you call the results of flow cytometry when only one fluorescent marker is used? what about when two or more markers are used? |
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Definition
One marker - results seen as histogram
two or more marker - scattergram |
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Term
What is a normal CD4/CD8 ratio? |
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Definition
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Term
What does a precipitin reaction look for? what percentage of antibody to antigen must there be for optimum reaction? |
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Definition
A precipitin reaction looks for a lattice of antibody-antigen (immune complex) forming a precipitate. For this reaction, antigen is in soluble form.
There should be equivalent concentrations of antigen and antibody to form a precipitate. |
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Term
What are some applications of antigen-antibody reactions? |
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Definition
- Blood typing
- Coombs direct/indirect test (Rh factor)
- Measure rheumatoid factor
- C reactive peptide
- antibodies to treponema pallidum
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Term
What are some applications for ELISA? |
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Definition
measure antibodies to virus (ie HIV or hepatitis) |
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Term
What is the purpose of immunofluorescence/immunohistochemistry? What is one of its applications? |
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Definition
Purpose: look at exact location and type of cell in situ
Applications: study proteins in cancers. |
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Term
For a positive western-blot of HIV, what markers must be detected? |
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Definition
p24 and either gp41, gp120 or gp160 |
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Term
True or false. A positive ELISA for HIV antibodies is confirmation for diagnosis of HIV. |
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Definition
False.
a positive ELISA must be followed with a western-blot to confirm. |
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