The Percentage of CD4 Positive Lymphocytes Is Determined by Flow

question 28

Multiple Choice

The percentage of CD4 positive lymphocytes is determined by flow cytometry using staining with fluorescent-tagged antibodies against CD3 and CD4 followed by whole blood RBC lysis. What calculations does the dual platform use to determine the absolute number of CD4 positive cells?

• A) Absolute CD4 count 100
• B) Number of CD4+ cells 100
• C) Absolute lymphocyte count % CD4+ lymphocytes/100
• D) % lymphocytes % CD4+ lymphocytes/100

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Definitions:

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Least-Squares Regression Line

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