Lymphocytes

Question 1

3 types of lymphcytes

Answer 1

B Cells

T Cells

NK Cells

Question 2

_______ account for 10% to 40% of blood lymphocytes

Answer 2

B cells

Question 3

In mammals, B cells originate in the ___________ but mature within ____________ or in the _________ before migrating to the secondary lymphoid organs.

Answer 3

bone marrow

Peyer’s patches

bone marrow

Question 4

After maturing, T cells leave the_______, and accumulate in the paracortex of ____________, the periarteriolar lymphoid sheaths of the ________, and the interfollicular areas of _____________

Answer 4

After maturing, T cells leave the thymus, and accumulate in the paracortex of lymph nodes, the periarteriolar lymphoid sheaths of the spleen, and the interfollicular areas of Peyer’s patches.

Question 5

NK cells probably originate from the same stem cells as_______ but do not undergo ________________

Answer 5

T cells

thymic processing

Question 6

________ account for 60% to 80% of the lymphocytes in blood

Answer 6

T cells

Question 7

B cells predominate in the _______________, in follicles within the ______________ and ___________, and in the marginal zone of the ______________ of the spleen.

Answer 7

B cells predominate in the cortex of lymph nodes, in follicles within the Peyer’s patches and spleen, and in the marginal zone of the white pulp of the spleen.

Question 8

The loss of ___________ immunity as a result of neonatal thymectomy first demonstrated the existence of T lymphocytes.

Answer 8

cell-mediated immunity

Question 9

Cell surface receptors are characterized through the use of an instrument called a ______________.

Answer 9

flow cytometer

Question 10

__________ are simply soluble BCRs

Answer 10

antibodies

Question 11

NK cells do not have ______________ like T and B cells. In contrast, they have ____________ that can bind molecules expressed on ____________ cells but not on _____________ cells

Answer 11

NK cells do not have antigen receptors like T and B cells. In contrast, they have receptors that can bind molecules expressed on healthy normal cells but not on diseased, abnormal cells

Question 12

Another protein, CD4, is found only on _________. CD4 molecules are receptors for ______________________ molecules on _______________ cells.

Answer 12

Another protein, CD4, is found only on helper T cells. CD4 molecules are receptors for major histocompatibility complex (MHC) class II molecules on antigen-presenting cells.

Question 13

A third protein, CD8, is, in contrast, only expressed on ___________. CD8 molecules are receptors for _____________

Answer 13

Cytotoxic T-cells

MHC class I molecules

Question 14

An elevated CD4 count implies ____________ lymphocyte reactivity because ________ cells predominate, whereas a high CD8 count implies __________ lymphocyte reactivity

Answer 14

An elevated CD4 count implies increased lymphocyte reactivity because helper cells predominate, whereas a high CD8 count implies depressed lymphocyte reactivity

Question 15

_______ is expressed in large amounts on all three lymphocyte populations.

Answer 15

CD45

Question 16

Fc receptors (FcR) are…

Answer 16

Lymphocyte receptors that bind to the Fc region on antibody molecules

Question 17

B cell mitogens

Answer 17

pokeweed

lipopolysaccharide

Question 18

antigens recognized by B cells

Answer 18

free foreign proteins

Question 19

tolerance induction of B cells

Answer 19

difficult

Question 20

B cell progeny

Answer 20

plasma cells

memory cells

Question 21

secreted products of B cells

Answer 21

immunoglobulins

Question 22

Mitogens of T cells

Answer 22

phytohemagglutinin

concanavain A

BCG vaccine

pokeweed

Question 23

antigens recognized by T cells

Answer 23

processed foreign proteins in MHC molecules

Question 24

tolerance induction of T cells

Answer 24

easy

Question 25

T cell progeny

Answer 25

effector T cells

memory T cells

Question 26

secreted products of T cells

Answer 26

cytokines

Question 27

TCR antigen-binding chains

Answer 27

paired α and β peptide chains (TCR α/β)

paired γ and δ chains (TCR γ/δ)

Question 28

BCR antigen-binding chains

Answer 28

heavy chains (γ, µ, α, ε, and δ)

Question 29

CD32 (FcγRII) is found on _______, __________ and ___________. It has a moderate affinity for _______ and will therefore only bind immune complexes (antibody molecules attached to an antigen)

Answer 29

found on B cells, dendritic cells, and macrophages

moderate affinity for IgG

Question 30

By prolonging and stabilizing cell interactions, binding of _______ permits successful antigen recognition

Answer 30

integrins

Question 31

β1-integrins

Answer 31

β1 chain (CD29)

α chain (CD49)

bind cells to extracellular matrix proteins such as fibronectin, laminin, and collagen

Question 32

β2-integrins

Answer 32

β2 chain (CD18)

α chain (CD11)

leukocytes to vascular endothelium

T cells to antigen-presenting cells

example: intercellular adhesion molecule-1 (ICAM-1) on vascular enothelium

Question 33

The emigration of lymphocytes from the bloodstream into tissues is regulated by _________, ____________ and ___________.

Answer 33

P-selectin (CD62P), L-selectin (CD62L), and E-selectin (CD62E)

Question 34

Which selectins are found on vascular endothelial cells?

Answer 34

P- and E-selectins

Question 35

________ binds lymphocytes to high endothelial venules in lymphoid organs

Answer 35

L-selectin

Question 36

lectins

Answer 36

bind to cell surface glycoproteins and trigger cell division