Deck 8: Lymphocytes

Question 1

The commitment of a lymphocyte precursor cell to a T lymphocyte can be defined based on:

A) Rearrangement of the gene loci for the TCR
B) Rearrangement of the immunoglobulin gene
C) Presence of CD 19 and CD 10 by flow cytometry
D) Presence of TdT

Answer 1

Rearrangement of the gene loci for the TCR

Question 2

Which of the following is a characteristic of NK cells?

A) They are effector cells of adaptive immunity.
B) They are capable of antibody synthesis.
C) They make up the majority of lymphocytes in peripheral blood.
D) Mature NK cells have potent lytic activity.

Answer 2

Mature NK cells have potent lytic activity.

Question 3

Natural killer cells recognize and kill antigens with attached IgG. This mechanism is described as:

A) Phagocytosis
B) Cyanosis
C) Antibody-dependent cell-mediated toxicity
D) Innate immune response

Answer 3

Antibody-dependent cell-mediated toxicity

Question 4

Which of the following is a characteristic of T lymphocytes?

A) Phagocytosis of bacteria
B) Antibody synthesis
C) Cytokine secretion
D) Few in number within peripheral blood

Question 5

Which two CD markers are used to differentiate helper T cells and cytotoxic T cells?

A) CD1 and CD3
B) CD4 and CD8
C) CD10 and CD19
D) BCR and TCR

Question 6

T, B, and NK lymphocytes can be differentiated by:

A) Morphology
B) Flow cytometry
C) Cytochemistry
D) Cytogenetic karyotype

Question 7

What cell has CD8 on its surface?

A) T-helper cell
B) B cell
C) Macrophage
D) Cytotoxic T cell

Question 8

An instrument printout on an adult shows a normal WBC count with a lymphocyte count of 30%. What can be concluded from this?

A) The patient is suffering from an infection.
B) There is a normal lymphocyte concentration.
C) The patient is an infant.
D) The patient has leukemia.

Question 9

A blood sample from a 5-month-old infant indicates a WBC count of 12.5 10⁹/L with 65% lymphocytes. What can you conclude from this?

A) The infant is normal.
B) The infant has an infection as indicated by the elevated WBC count.
C) The infant has a malignancy in the lymphocyte lineage.
D) There is not enough information to draw accurate conclusions.

Question 10

Which of the following terms describes an absolute increase in the number of lymphocytes?

A) Neutropenia
B) Eosinophilia
C) Leukocytosis
D) Lymphocytosis

Question 11

The lymphoid progenitor that gives rise to T, B, and NK lymphocytes is recognized as which of the following?

A) CFU_GM
B) CLP
C) CMP
D) CFU-T

Question 12

Which of the following describes the components used to construct an immunoglobulin?

A) 5 heavy chains
B) 2 light chains
C) 5 identical heavy chains with 2 identical light chains
D) 2 identical heavy chains with 2 identical light chains

Question 13

A blood sample from a 40-year-old white female has a WBC count of 10.2 10⁹/L and a lymphocyte percentage of 47%. What can be concluded from this?

A) The patient has both a relative and an absolute lymphocytosis.
B) The patient has only a relative lymphocytosis.
C) The patient has only an absolute lymphocytosis.
D) The relative and absolute counts are normal.

Question 14

Reactive lymphocytes differ from normal lymphocytes in that the reactive form can exhibit:

A) Vacuoles, a scalloped cell shape and an increase in basophilic cytoplasm
B) Condensed nuclear pattern with light pink cytoplasm
C) Many granules, deep basophilic cytoplasm, and blast-like nucleus
D) Condensed nuclear chromatin, eccentric nucleus, and deep blue cytoplasm

Question 15

A patient with infectious mononucleosis would most likely produce which of the following?

A) IgD antibodies
B) Polyclonal antibodies
C) Monoclonal antibodies
D) IgE antibodies

Question 16

Which of the following is found on early T-cell precursors?

A) CD2
B) CD4
C) CD8
D) CD34

Question 17

Which cell line matures and differentiates upon exposure to antigen?

A) Neutrophilic
B) Basophilic
C) Monocytic
D) Lymphocytic

Question 18

Which of the following describes the distribution of lymphocytes within the body?

A) 75% exist in peripheral blood, 25% in lymph nodes and spleen
B) 50% exist in the circulating pool, 50% in the marginating pool
C) 95% are found in the lymph nodes and spleen, 5% in the peripheral blood
D) 80% are short-lived, 20% are long lived

Question 19

Which of the following is considered the "pan-B" antigen?

A) CD4
B) CD8
C) CD19
D) CD10

Question 20

The class of immunoglobulins is determined by:

A) The number of B cells containing the antibody
B) The complexity of the antibody
C) The isotype of the heavy chain
D) The specificity of the variable region

Question 21

What are three defining characteristics that would help the laboratory professional differentiate between a blast and an activated lymphocyte?

Question 22

Compare and contrast the five isotypes of immunoglobulins. Include structure, function, and leukocyte interaction in your answer.

Question 23

List the subtypes of lymphocytes in normal adult peripheral blood from most numerous to least numerous.

Question 24

Describe the immunologic features and functions of NK cells.

Question 25

What is the difference between polyclonal antibodies and monoclonal antibodies? List examples of disorders that generate each type of antibody in your answer.