Exam # 1

Question 1

Which TLRs recognize pathogenic nucleic acids?

Answer 1

TLRs 3,7,9

Question 2

Which molecule is important for tight neutrophil adhesion?

Answer 2

LFA-1

Question 3

The Fab fragment of the antibody molecule

Answer 3

binds antigen

Question 4

What is the best definition of an endogenous Pyrogen?

Answer 4

Cytokines made by the host that increase body temperature

Question 5

Mannose Binding Lectin, an example of secreted PRR, helps in facilitating pathogen uptake by a processes known as…

Answer 5

Opsonization

Question 6

Most Toll like receptors signal through an adaptor protein called MyD88. However, _____ is a MyD88 independent signaling receptor.

Answer 6

TLR3

Question 7

Junctional Diversity during gene rearrangement results from the addition of _____

Answer 7

P and N nucleotides

Question 8

Which of the following corresponds to the antigen binding site of immunoglobulins?

Answer 8

VH; VL

Question 9

The Signaling pathways triggered by toll like receptors typically result in activation of the following pairs of which transcription factors?

Answer 9

NFkB and AP-1

Question 10

The 110 AAs that make up the Fab fragment of the H and L chains consist of ______ and ______ regions

Answer 10

framework ad hypervariable

Question 11

B Cells are said to be anergic if they have seen/ undergone:

Answer 11

Moderate levels of soluble antigen followed by migration to the periphery

Question 12

The Process by which a pathogen stimulates only those lymphocytes with receptors specific for that pathogen is called

Answer 12

Clonal selection

Question 13

Early, innate events during viral infection of host cells involves induction of the cytokine ______ that activates _______ to kill virally infected cells

Answer 13

IFN-a/B, NK cells

Question 14

Which Cytokine is important for B cell development?

Answer 14

IL-7

Question 15

What would be the phenotype of a mouse (or a person) that lacks tdt?

Answer 15

Less diversity in the lymphocyte repertoire

Question 16

Name the three categories of PRRs and cite an example of each

Answer 16

1) Endocytic : Macrophage Mannose Receptor; 2) Signaling: TLRs; 3) Secreted: Mannose Binding Lectin

Question 17

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?)

Answer 17

Defect in BTK gene; located in long arm of chromosome xq22

Question 18

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?

Answer 18

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.

Question 19

XLA phenotype

Answer 19

No tonsils; mutation in BTK; absence of B cells, normal T cell levels

Question 20

Omenn Syndrome phenotype

Answer 20

red rash, mutation in Rag1/2; absence of B cells, low levels of T cells.

Question 21

What binding receptor is on a rolling leukocyte? What is its ligand?

Answer 21

LFA-1; ICAM-1

Question 22

What is CXCL8’s role in leukocyte rolling?

Answer 22

CXCL8 is a chemokine that binds to leukocyte and causes LFA-1 to go from low affinity to high affinity binding.

Question 23

What is the first checkpoint in B cell development?

Answer 23

The large pre B cell; tests for the presence of a heavy rearranged chain