Exam # 1 Flashcards
Which TLRs recognize pathogenic nucleic acids?
TLRs 3,7,9
Which molecule is important for tight neutrophil adhesion?
LFA-1
The Fab fragment of the antibody molecule
binds antigen
What is the best definition of an endogenous Pyrogen?
Cytokines made by the host that increase body temperature
Mannose Binding Lectin, an example of secreted PRR, helps in facilitating pathogen uptake by a processes known as…
Opsonization
Most Toll like receptors signal through an adaptor protein called MyD88. However, _____ is a MyD88 independent signaling receptor.
TLR3
Junctional Diversity during gene rearrangement results from the addition of _____
P and N nucleotides
Which of the following corresponds to the antigen binding site of immunoglobulins?
VH; VL
The Signaling pathways triggered by toll like receptors typically result in activation of the following pairs of which transcription factors?
NFkB and AP-1
The 110 AAs that make up the Fab fragment of the H and L chains consist of ______ and ______ regions
framework ad hypervariable
B Cells are said to be anergic if they have seen/ undergone:
Moderate levels of soluble antigen followed by migration to the periphery
The Process by which a pathogen stimulates only those lymphocytes with receptors specific for that pathogen is called
Clonal selection
Early, innate events during viral infection of host cells involves induction of the cytokine ______ that activates _______ to kill virally infected cells
IFN-a/B, NK cells
Which Cytokine is important for B cell development?
IL-7
What would be the phenotype of a mouse (or a person) that lacks tdt?
Less diversity in the lymphocyte repertoire
Name the three categories of PRRs and cite an example of each
1) Endocytic : Macrophage Mannose Receptor; 2) Signaling: TLRs; 3) Secreted: Mannose Binding Lectin
A disease known as X- linked Agammaglobulinemia is characterized by a lack of antibodies, but normal numbers of CD4 and CD8 T cells. a. what is the defect in these patients (In which gene does the defect reside?)
Defect in BTK gene; located in long arm of chromosome xq22
A disease known as X- linked Agammaglobulinemia is characterized by a lack of antibodies, but normal numbers of CD4 and CD8 T cells. b. What is the developmental consequence of this defect? In other words, at which stage in lymphocyte development will this defect manifest?
Post pre B cell receptor; BTK lies downstream of the Pre-B cell receptor and causes signals to be transduced that allow the B-Cell to survive. XLA lacks or has a mutation in BTK that does not allow this to occur.
XLA phenotype
No tonsils; mutation in BTK; absence of B cells, normal T cell levels
Omenn Syndrome phenotype
red rash, mutation in Rag1/2; absence of B cells, low levels of T cells.
What binding receptor is on a rolling leukocyte? What is its ligand?
LFA-1; ICAM-1
What is CXCL8’s role in leukocyte rolling?
CXCL8 is a chemokine that binds to leukocyte and causes LFA-1 to go from low affinity to high affinity binding.
What is the first checkpoint in B cell development?
The large pre B cell; tests for the presence of a heavy rearranged chain
