Deck 34: Applications of Flow Cytometry to Hematology and Hemostasis

Question 1

Immunophenotyping is a staining approach that uses antibodies chemically linked to fluorochromes to recognize cell types by identifying specific ______________ on the surface of the cell or inside the cell.

A) Antibodies
B) Antigens
C) Haptens
D) Light chains

Answer 1

Antigens

Question 2

______________ occurs when a chemical absorbs light, causing its electrons to be excited briefly to a higher, less-stable energy state.

A) Electronegativity
B) Light scatter
C) Fluorescence
D) Refraction

Answer 2

Fluorescence

Question 3

While evaluating data from an analysis, the analyst suspects spectral bleed-over has occurred. What can be done so that each detector only measures the signal for the appropriate fluorescent dye?

A) Increase the voltage to each detector
B) Properly set the fluorescence compensation control
C) Decrease the threshold setting
D) Remove the optical filters

Answer 3

Properly set the fluorescence compensation control

Question 4

Which of the following is an abnormal result for lymphocyte subset percentage in adult donors?

A) CD3 (70%)
B) CD4 (42%)
C) CD8 (20%)
D) CD19 (60%)

Question 5

Which collection tube is used for enumeration of leukocyte subpopulations for blood and bone marrow?

A) EDTA tube (purple)
B) Heparinized tube (green)
C) Sodium citrate tube (blue)
D) Red top tube

Question 6

The specimen of choice for analysis of cell function by flow cytometry is:

A) Ethylenediaminetetraacetic acid (EDTA)-anticoagulated whole blood
B) Sodium heparinized whole blood
C) Thrombonized packed cells
D) Ficoll-treated packed cells

Question 7

Which of the following surface markers is specific for progenitor cells?

A) CD5
B) CD10
C) CD19
D) CD34

Question 8

In DNA analysis by flow cytometry, better quantitation of fluorescence is achieved by measuring:

A) The area of the pulse detected
B) The height of the pulse detected
C) The appearance time of the pulse detected
D) The extinction of the pulse detected

Question 9

Flow cytometry is a technology that provides rapid measurement of:

A) Physical characteristics of cells
B) Cellular stain affinities
C) Suspension fluidics
D) Sample laminar flow rate

Question 10

Cell suspensions prepared from lymphoid tissues should be processed quickly to avoid artifacts caused by _____________________.

A) Cell aggregation
B) Cellular swelling
C) Nonviable cells
D) Viable cells

Question 11

In general, the greater the side-scattered (SSC) signal:

A) The smaller the cell
B) The larger the cell
C) The more complex a cell's internal structure
D) The more simple a cell's internal structure

Question 12

In flow cytometry, forward-angle light scatter provides information relevant to cell __________________.

A) Shape
B) Size
C) Hemoglobin content
D) Iron content

Question 13

Which of the following is a software feature that allows the operator to focus on a single population of cells?

A) Data analysis
B) Quadrant statistics
C) Gating
D) Fluorescence compensation

Question 14

The forward-scattered (FSC) and side-scattered (SSC) values for lymphocytes compared with those for monocytes and neutrophils are:

A) Lower
B) Higher
C) Identical
D) Indeterminate

Question 15

The dyes utilized by flow cytometry instruments include:

A) Fluorescein isothiocyanate (FITC)
B) Phycoerythrin (PE)
C) Propidium iodide (PI)
D) All of the above

Question 16

Residual white blood cells are detected in red blood cell packs by flow cytometry based on the presence of:

A) Lipids
B) Lysosomes
C) DNA
D) Granules

Question 17

In HIV infection, what is monitored to determine if antiviral treatment should be started?

A) CD8 absolute counts
B) CD3 percentage
C) CD4 absolute counts
D) CD8 percentage

Question 18

Malignant cells tend to have abnormal amounts of DNA. This is termed __________.

A) Aneuploidy
B) Ploidy
C) Paresis
D) Karyorrhexis

Question 19

In DNA analysis using flow cytometry, what type of signal is expected in cells with large amounts of DNA?

A) A weak signal
B) A strong signal
C) No signal
D) Signal type cannot be determined with given information

Question 20

SSC is related to what characteristic of the blood cell?

A) Size of the cell
B) Immunophenotype of the cell
C) Nuclear size of the cell
D) Granularity of the cell