2.4.3 Diseases of T Cell Deficiencies Flashcards
What is this image indicative of?
CXR that shows absence of thymic shadow
Is this CXR normal or abnormal?
Normal CXR showing a thymic shadow
Is it normal for a newborn baby to have normal levels of IgG with almost absent levels of other antibodies?
It is normal for a baby to have normal levels of IgG, because this comes from the mother
T cell deficiencies will lead to what?
Opportunistic infections
What needs to be accounted for in vaccinating a child with SCID?
Attenuated vaccines can lead to severe or fatal infections
What are the important criteria for diagnosing SCID?
Absolute lymphocyte count is less than 2500
T cells making up less that 20% of lymphocytes
Lymphocyte stimulation to mitogens is less than 10% of normal control
Absence of thymus on CXR
How to tell maternal engrafted cells from normal infant cells?
Maternally engrafted cells have CD45RO (memory phenotype) and normal infant are CD45RA
What causes X-linked SCID and how will this affect T, B, and NK cell development?
T-B+NK-
This is a result from a defect on X chromosome encoding the cytokine receptor subunit gamma chain, IL2 receptor gene
How to differentiate X-linked SCID from JAK-3 SCID?
Function STAT5 tyrosine phosphorylation assay
ADA deficiency leads to what type of T, B and NK cell deficiency and what characterizes it?
T-B-NK-
Accumulation of adenosine, 2-deoxyadenosine and 2-o-methyladenosine. Latter metabolites leading directly or indirectly to apoptosis of thymocytes and circulating lymphocytes
JAK3 deficiency leads to what T, B, and NK cell development and what is characteristic of it?
T-B+NK-
Downstream cytokine signaling issue
IL-7 Receptor Alpha Chain Deficiency will lead to what T, B and NK cell development?
T-B+NK+
IL-7 is a specific receptor for what cells?
T cell development
RAG-1/2 SCID will lead to what T, B and NK cell development?
T-B-NK+
Defective RAG proteins will lead to what?
VDR rearrangement issues of T and B cell receptors
