Basic Science I Flashcards
What are the structural differences between MHC class I and MHC class II molecules?
Class I has 3 alpha chains and one beta chain
Class II has 2 alpha and 2 beta chains
A high percentage of double negative alpha/beta T cells is associated with what condition?
ALPS
Where is antigen loaded onto class 1 MHC?
endoplasmic reticulum
What protein transfers intracellular antigen from the proteosome to the ER?
TAP1/TAP2
What is the purpose of the invarient chain in MHC II antigen presentation?
protects the binding cleft until peptide can be loaded
Where is antigen loaded onto MCH class II molecules?
phagolysosome
What interaction between B and T cells induces class switching?
T cell CD40L binds to B cell CD40
Mutations in Tbx1 lead to what disease?
DiGeorge
Autoimmune Polyendocrinopathy-Candidiasis-Ectodermal Dystrophy (APECED) is due to a mutation in which gene?
AIRE - autoimmune regulator
What is the function of Artemis?
opens the hairpin to allow for VDJ recombination
What is the function of RAG1/RAG2?
cleaves VDJ regions during recombination
What is formed from the remaining 12/23 spacer after recombination?
TREC
Which CD markers are present on T cells during positive selection?
CD3, CD4, CD8
Which CD markers are present on T cells during negative selection?
CD3 and either CD4 or CD8
Autoimmunity occurs with failure of which? - positive selection, negative selection
negative selection - when T cells with high affinity for self are deleted
NKT cells recognize antigen presented on what? What kind of antigen do they recognize?
CD1d; lipid
Which cytokine do innate lymphoid cells primarily produce?
IL-22 - maintains epithelial integrity
IL-17 or IL-17R defect leads to what disease?
chronic mucocutaneous candidiasis
IFN-gamma production is induced by which STAT and transcription factors?
STAT1/4; Tbet
IL-4,5, and 13 production is induced by which STAT and transcription factor?
STAT6; GATA3
TGFbeta and IL-10 production is induced by which STAT and transcription factor?
STAT5; FOXP3
Bcl6 and IRF4 transcription factors are activated by which STAT and produce which cytokines?
STAT3/4/1; IL-21, 4, 10
STAT6 is induced by which cytokine?
IL-4
STAT5 is induced by which cytokine(s)?
TGFb and IL-2
STAT3 is induced by which cytokine(s)?
IL-23 and IL-1b
Costimulation of T cells occurs by binding what to CD80 and CD86?
CD28
Binding of CD28 to CD80 or CD86 causes expression of what other CD marker?
CD40L for costimulation
Which interleukin drives monoclonal expansion of T cells after activation?
IL-2
Which molecule is upregluated on T cells when homing to the lymph nodes?
CCR7 and LFA1
What do CCR7 and LFA1 bind to when T cells home to the lymph node?
CCL19 and CCL21
Which cellular marker is an indicator of T cell exhaustion?
PD1
Which enzyme is responsible for somatic hypermutation and affinity maturation?
AID (activation-induced cytidine deaminase)
Which IgG subclasses are good at complement fixation?
IgG1 and IgG3
