Week 10 Flashcards
What was flow cytometry originally designed to measure?
measure physical properties of cells
• Ability to deflect light
• Influenced by size and internal structure
Flow cytometry can rapidly analyse large cell populations and classify and quantify them according to what 3 things?
- Size
- Internal structures and complexity
- Antigenic characteristics
What are the 2 ways flow cytometry is used in leukaemias?
- Identify clonal populations of cells
* Detect and quantitate minimal residual disease
Immunophenotypes often correlate with what 2 types of abnormalities?
- Cytogenetic abnormalities
* Morphologic abnormalities
In specimen staining what are the two types of markers used?
surface and intracellular
Surface marker specimen staining is usually a cocktail of?
Fluorochrome-conjugated monoclonal antibodies
Intracellular markers requires an additional step to make cell membrane what?
permeable to staining agents
CD4 and CD22 are examples of what?
Monoclonal antibodies
The CD in CD22 stands for what?
Cluster of differentiation
Can flow cytometry define antigen expression on large and complex populations of
viable cells?
Yes
Many antigens can be detected simultaneously on individual cells with flow cytometry. T-F
T
In regards to light scatter
• Forward scatter =
• Side scatter =
- Forward scatter = Proportional to particle size
* Side scatter = Surface complexity • Internal structures • Nuclear folding • Granules • Vacuoles
What are 3 ways gating signals that are detected be sorted?
- Size
- Cytoplasmic complexity
- Antigen expression
Pluripotent stem cells usually express what markers?
- CD34
- CD38
- CD117
- HLA-DR
CD45 is pan haemopoietic except for what 2 cell types?
erythrocytes, platelets
Mature B-cells express what 2 CD markers and what Ig?
CD19 CD20
• Mix of Kappa and lambda light
chain Ig
T-helper cells express what CD marker?
• CD4
T-suppressor cells express what CD marker?
• CD8
Do lymphocytic neoplastic cell populations demonstrate a single dominant cell type or a wide variety of cell types?
single
CD3 is most specific what cell type?
T-cell marker
Besides CD3 list some other T-cell markers:
• CD1a CD2 CD5 CD7 CD8
CD3 and CD5 are pan-mature to what cell line?
T-cell markers
T-cell acute lymphoblastic leukaemia would have what 4 markers?
• CD2 CD4 CD5 CD8
Which of the following is true of CD45 antigen?
a) It is present on every cell population of the bone marrow
b) It is expressed on all haemopoietic cells except megakaryocytes and late erythroid precursors
c) It is not measured routinely in flow cytometry
d) It may be present on non-haemopoietic cells
b) It is expressed on all haemopoietic cells except megakaryocytes and late erythroid precursors
Which of the following is true of flow cytometry gating?
a) It is best defined as selection of a target population for flow cytometry analysis
b) It can only be done at the time of data acquisition
c) It can only be done at the time of final analysis and interpretation of flow cytometric data
d) It is accomplished by adjusting flow rate
a) It is best defined as selection of a target population for flow cytometry analysis
Collection of ungated events:
a) Facilitates comprehensive analysis of all cells
b) Does not help in the detection of unexpected abnormal populations
c) Allows the collection of data on a large number of rare cells
d) Is used for leukaemia diagnosis only
a) Facilitates comprehensive analysis of all cells
During the initial evaluation of flow cytometric data, cell size, cytoplasmic complexity, and expression of CD45 antigen are used to define cell subpopulations. Which of the following parameters defines cytoplasmic complexity / granularity?
a) SS
b) FS
c) CD45
d) HLA-DR
a) SS - side scatter
The most important distinguishing feature of a mature neoplastic B-cell population is:
a) The presence of a specific immunophenotype with expression of CD19 antigen
b) A clonal light chain expression (i.e. exclusively kappa- or lamda- positive population)
c) A clonal T-cell receptor expression
d) Aberrant expression of CD5 antigen on CD19+ cells
b) A clonal light chain expression (i.e. exclusively kappa- or lamda- positive population)
