CHAPTER 13: Flow Cytometry and Laboratory Automation Flashcards
Flow cytometry characterizes cells on the basis of which of the following?
a. Forward and 90-degree side scatter of an interrupted beam of light
b. Front-angle scatter only of an interrupted light beam
c. Absorbance of light by different types of cells
d. Transmittance of light by cells in solution
a. Forward and 90-degree side scatter of an interrupted beam of light
Forward-angle light scatter is an indicator of cell
a. granularity.
b. density.
c. size.
d. number.
c. size.
What is the single most important requirement for samples to be analyzed on a flow cytometer?
a. Whole blood is collected into a serum-separator tube.
b. Cells must be in a single-cell suspension.
c. Samples must be fixed in formaldehyde before processing.
d. Blood must be kept refrigerated while processing.
b. Cells must be in a single-cell suspension.
Which statement represents the best explanation for a flow cytometer’s ability to detect several cell surface markers at the same time?
a. The forward scatter can separate out cells on the basis of complexity.
b. One detector can be used to detect many different wavelengths.
c. For each marker, a specific fluorochrome-antibody combination is used.
d. Intrinsic parameters are separated out on the basis of the amount of side scatter.
c. For each marker, a specific fluorochrome-antibody combination is used.
Which of the following cell surface markers would be present on a population of T helper (Th) cells?
a. CD3 and CD4
b. CD3 and CD8
c. CD3 only
d. CD4 only
a. CD3 and CD4
If an analyzer consistently indicates a positive test when the analyte in question is not present, this represents a problem with
a. sensitivity.
b. specificity.
c. reportable range.
d. precision.
b. specificity.
All of the following are clinical applications for flow cytometry except
a. fetal hemoglobin.
b. immunophenotyping of lymphocyte subpopulations.
c. HIV viral load analysis.
d. enumeration of stem cells in a peripheral blood mononuclear cell product.
d. enumeration of stem cells in a peripheral blood mononuclear cell product.
The various signals generated by cells intersecting with a flow cytometry laser are captured by
a. bandwidth waves.
b. wave channels.
c. photomultiplier tubes.
d. flow cells
c. photomultiplier tubes.
Analysis of flow cytometer data of cells can be filtered in many ways by using a method of
a. “gating” in a dot plot.
b. banding of a histogram.
c. single-parameter histogram monitoring.
d. automatic sampling.
a. “gating” in a dot plot.
A newer flow cytometry technology that has the potential to detect over 500 analytes from one sample of blood is called a/an
a. RBC fragmentation assay.
b. Dihydrorhodamine 123.
c. sucrose test.
d. cytometric bead array.
d. cytometric bead array.
Many flow cytometry laboratories now use the CD45 marker in combination with SSC in differentiating various populations of WBCs to replace which of the following combinations?
a. CD4 + SSC
b. CD4 + FSC
c. FSC + SSC
d. FSC + CD45
c. FSC + SSC
Which cell surface marker is present on cells seen in hairy cell leukemia?
a. CD138
b. CD33
c. CD103
d. CD34
c. CD103
CD45 is a pan-leukocyte marker expressed on WBCs in varying levels or amounts of expression, based on
a. size of a cell.
b. granularity of a cell.
c. maturity and lineage of a cell.
d. malignancy of a cell.
c. maturity and lineage of a cell.
Which of the following statements best describes a single-parameter histogram?
a. Each event is represented by a dot.
b. Data is distributed in four quadrants.
c. Positive and negative events are plotted on the x and y axis.
d. A chosen parameter is plotted versus the number of events.
d. A chosen parameter is plotted versus the number of events.
How many fluorochromes (colors) are current clinical flow cytometers capable of detecting?
a. 2
b. 6
c. 8
d. 10
d. 10
