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14 Cards in this Set
- Front
- Back
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What is X-Linked Agammaglobulinemia (XLA)?
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An X-linked defect in B-Cell development which prevents differentiation and proliferation of B-Cells, absence of plasma cells, absence of germinal centers, and very low levels of circulating immunoglobulins.
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Why would a patient with XLA present with persistent infection?
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Lack of Ab's lead to an inability to opsonize capsular antigens and suboptimal binding to C3b and Fc-gamma receptors on neutrophils resulting in ineffective phagocytosis.
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What kind of therapy is appropriate for XLA?
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IgG replacement therapy (passive immunity).
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What is Severe Combined ImmunoDeficiency (SCID)?
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Insufficient lymphocytes resulting in a broad inability to respond to infection early after birth.
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What cells will be markedly reduced in SCID?
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Neutrophils, platelets, lymphocytes due to an early lineage defect in hemopoietic stem cells in the bone marrow.
RBC's are not affected due to an early break in lineage. |
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What would an electrophoresis of a patient with SCID look like?
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Reduced globulins.
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What would a FACS analysis (separate and measure different cell types) of SCID look like?
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Absence of all lymphocytes.
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What is Mixed Lymphocyte Testing and why is it useful?
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Test to find the best donor-recipient match. Mix each blood and find the least amount of proliferation (with one side radioactively suppressed).
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What is MHC Typing and what is it useful for?
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One parent gives a set of MHC's to the child, and it helps to determine positive matches for organ transplant. What else??
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What are the symptoms of a Plasma cell defect?
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High number of circulating lymphocytes, but low serum levels of IgG.
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What prevents B-Cell maturation in patients with a Plasma cell defect?
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No germinal centers for isotype switching and terminal differentiation.
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What is the difference between XLA and plasma cell defects?
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XLA would have no Ab's at all.
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Where might the possible defects be in the plasma cell defect?
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Defective B-cell differentiation, defective germinal centers, defective cytokines, defective B-cell to Th2 cell cross-talk.
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What are patients with plasma cell defects more susceptible to?
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Lymphoma.
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