Hematology Lab testing- Flow cytometry

Which of the following represents the percent population of T-helper cells in this sample data? absolute lymphocyte count= 2.4 x 109/L %CD3 = 60%CD4 = 40%CD8 = 20

40%

The principle behind the diagnosis of Paroxysmal Nocturnal Hemoglobinuria (PNH) by flow cytometry is:

Using a fluorescein labeled proaerolysin variant to selectively bind to GPI anchor proteins

Flow cytometry is a useful tool in the study all of the following disorders, EXCEPT?

Viral hepatitis

In flow cytometry, the granularity of a cell is indicated by which of the following?

Side scatter

In the flow cytometric analysis, which of the following data can be collected?

Size and granularity of the cell by forward/side scatters

It has already been established that the gated cell population is lymphocytic in nature. CD19 and CD20 cell surface antigens both appear on what type of lymphocytes?

B cells

During data analysis in flow cytometry, how are cells gated?

By placing a gate around cells with the same light-scattering.

Which of the following markers is associated with normal mature B cell expression?

CD19

Which of the following phenotypes is most indicative of a natural killer (NK) cell?

CD2+ CD3- CD11b+ CD16+

Which one of the following antigen markers is BEST associated with stem cells?

CD34

When using a flow cytometer, forward scatter measures which of the following parameters?

Cell size

A population of small lymphocytes is gated for further evaluation in the flow cytometry laboratory. The scatterplot for one of the evaluations is shown on the right. How would you interpret this scatterplot?

Cells in the gated population are co-expressing CD5 and CD20.

The image on the right contains the fluorescence data from CD45 from a flow cytometry analysis. Note that virtually all cells in the gated population have CD45 surface antigens. These cells could therefore be any of the following EXCEPT:

Erythrocytes

Which of the following laboratory tests would be most helpful in determining the number of T cells in circulation?

Flow cytometry

Which of the following assays is more sensitive and specific for the diagnosis of Paroxysmal Nocturnal Hemoglobinuria (PNH)?

Flow cytometry for GPI-anchored proteins

What principle(s) of flow cytometry is employed when performing immuno-phenotyping?

Fluorescent antibody tagging and light scatter

Which white blood cell population would have the MOST side scatter when analyzed using flow cytometry?

Granulocytes

Laser light can be described by all of the following characteristics EXCEPT:

LASER is an acronym for light amplified by stimulated energy radiation

What cell population is gated in this peripheral blood sample case analyzed by flow cytometry?

Lymphocytes

During the 'staining' process prior to flow cytometry analysis of white blood cells, how are the erythrocytes treated?

Lysed

CD5 antigen is normally found on which of the following lymphocyte populations?

Mature T cells

The scatterplot that is pictured below represents results from a normal peripheral blood sample that was analyzed using flow cytometry. The cell that is indicated by the arrow on the right would fall into which of the circled areas?

Population C