Cells involved in Immune Responses Flashcards
What are the markers that identify B cells?
CD19, CD20, CD 21
Tregs use this to suppress other T cells
Cytotoxic T lymphocyte antigen 4 (CTLA4)
Transcription factors Tbet and STAT4 drive production of what T cell subset?
Th1
Transcription factors GATA3 and STAT6 drive production of what T cell subset?
Th2
Tfh cells help B cells make antibody through transcription factor Bcl-6. What does Bcl-6 do?
Causes down regulation of CCR7 and a upregulation of CXCR5
Which cells are induced by IL-6 and function in neutrophil recruitment and extracellular defense?
Th17
What do CD8 cells use to kill infected cells?
Perforin and granzyme
Which interleukin is involved in NK cell development?
IL-15
Which cellular markers identity NK cells?
CD16, CD56 (NCAM), natural cytotoxic receptors, killer inhibitory receptors. NOT CD3!
Which interleukin activates transcription factors Tbet and STAT4?
IL-12
Which interleukin activates transcription factors GATA3 and STAT6?
IL-4
Which interleukin activates transcription factors RORγT and STAT3?
IL-6, TGF-β
What type of antigens do you NKT cells recognize?
Glycolipids on CD1
Transcription factors RORγT and STAT3 drive production of what T cell subset?
Th17
Transcription factors FOXP3 and STAT5 drive production of what T cell subset?
Treg
Which cytokines activate transcription factors FOXP3 and STAT5?
TGF-β, IL-10
Which enzyme is responsible for adding nucleotides during junctional diversity?
TdT
Which enzymes cleave double-stranded DNA between coding segments and its recombination signal sequence?
RAG1/RAG2
What is the function of Artemis?
opens DNA hairpin at random site
Which enzyme removes nucleotides for junctional diversity?
endonuclease
What is positive selection?
ensures T cell is able to interact with MHC to avoid apoptosis
What is negative selection?
eliminates T cells that bind with high affinity to self antigen
What is the purpose of alternative splicing?
yields membrane vs. secretory Ig
What is the purpose of differential splicing
produces different Ig isotypes
Where does negative selection occur for T cells?
Medulla, which is also where AIRE functions
T cell death through neglect is mediated by what?
Caspase 9
What does caspase 8 do?
induced by repeated activation; increases expression of Fas/FasL
What markers identify monocytes?
CD14, CD16
What stimulates macrophage growth?
GM-CSF, monocyte colony stimulating factor
LPS binds to what on macrophages?
CD14, which is also a component of TLR4
What cytokine secreted by macrophages promotes granuloma formation?
TNFα
Which syndrome is characterized by high fever, hepatosplenomegaly, high ferritin and triglycerides and low fibrinogen?
Hemophagocytic lymphohistiocytosis (HLH)
Birbeck granules identify which subset of dendritic cells?
Langerhans
What markers identify dendritic cells?
B7.1 and B7.2 (CD80/CD86) - interacts with CD 28 on T cells to provide costimulation
What is the target of imatinib?
Kit (CD117) - receptor for cytokine stem cell factor
What markers identify mast cells?
kit (CD117), CD34
Which proto-oncogene is implicated in systemic mastocytosis?
c-kit, codes for kit
Which mast cell subset secretes only tryptase and where is it found?
MCt; found in respiratory and intestinal mucosa
Which mast cell subset secretes only chymase and where is it found?
MCc - found in lymph nodes, intestinal submucosa and salivary glands
Which mast cell subset secretes tryptase and chymase and where is it found?
MCtc - found in skin, eyes, blood vessels
What are the components of the IgE receptor?
α chain - binds to IgE
β chain
γ chain - signalling component
Which mediators released by mast cells are preformed?
Histamine, tryptase, carboxypeptidase, chymase, heparin, TNF
Which mediators released by mast cells are lipid-derived?
Prostaglandin D2, Leukotriene C4 and B4, Platelet-activating factor
What type of tryptase is elevated in anaphylaxis?
β-tryptase
Which mast cell mediator is both preformed and produced in the late phase?
TNF
Which mediators are produced by mast cells but not basophils?
tryptase, chymase, carboxypeptidase, heparin, PGD2, LTB4
What is contained in primary eosinophil granules
Charcot-Leyden crystals
What is used to detect the recent presence of eosinophils?
major basic protein
Eosinophils migrate to tissues in response to what?
RANTES (CCL-5) and eotaxin
What is contained in secondary eosinophil granules
major basic protein, eosinophil cationic protein, eosinophil peroxidase, eosinophil-derived neurotoxin
What is the #1 cause of peripheral eosinophilia in the US and worldwide, respectively?
drugs, parasitic infections
Neutrophils migrate into tissues via what?
IL-8 (CXCL-8), Sialyl-Lewis X, E & P selectin, LFA-1/ICAM-1
Neutrophil survival, differentiation and proliferation are stimulated by what?
IL-3, GM-CSF, G-CSF
Which neutrophil granules are enlarged in Chediak-Higashi syndrome?
Primary granules
Which neutrophil granules are absent in specific granule deficiency?
Secondary granules
Which helper T cell secretes cytokines that activate neutrophils?
Th17 cells
Classify mild, moderate and severe neutropenia by absolute neutrophil count
mild:
What markers identify NK T cells?
CD3, CD16, CD56 and usually CD4
Which subset of dendritic cells produces type 1 IFN during viral infections?
Plasmacytoid
Which X-linked disorder is characterized by small platelet volumIe, thrombocytopenia, eczema and infections?
Wiskott-Aldrich syndrome
ITP is due to antibodies to what?
Platelet GP2b3a - platelets are abnormally large
TTP is is due to autoantibodies to what?
ADAMTS13
Heparin induced thrombocytopenia is due to antibodies against what?
PF4
Which chemokines produced by keratinocytes are responsible for homing T cells to the skin? What are the corresponding receptors on the T cells?
CCL17 (TARC) and CCL22 (MDC);
cutaneous lymphocyte antigen (CLA), CCR4 and CCR10
What are the ligands for integrins?
ICAM and VCAM
What is the ligand for L-selectin?
Lialyl-Lewin X on high endothelial venules
What surface markers on the high endothelial venules and naive T cells are responsible for homing to the lymph nodes?
CCL19 and CCL21 on high endothelial venule and CCR7 on the naive T cell
