Calculating Absolute Cell Counts, continued

How to Subscribe
MLS & MLT Comprehensive CE Package
Includes 176 CE courses, most popular
$109Add to cart
Pick Your Courses
Up to 8 CE hours
$55Add to cart
Individual course$25Add to cart
Need multiple seats for your university or lab? Get a quote
The page below is a sample from the LabCE course Introduction to Flow Cytometry: Blood Cell Identification. Access the complete course and earn ASCLS P.A.C.E.-approved continuing education credits by subscribing online.

Learn more about Introduction to Flow Cytometry: Blood Cell Identification (online CE course)
Calculating Absolute Cell Counts, continued

Now that the absolute lymphocyte value has been calculated, the results from the flow cytometric analysis can be incorporated as follows:
Values from the flow cytometer analysis
  • %CD3 = 60% (CD3 positivity reflects total T cell percentage)
  • %CD4 = 40% (CD4 positivity reflects T-helper cell percentage)
  • %CD8 = 20% (CD8 positivity reflects cytotoxic T cell percentage)
*Note that 60% CD3 (total mature T cells) is further broken down into 40% CD4 (T-helper cells) + 20 % CD8 (cytotoxic T cells).
By using the following calculation, the absolute (Abs) cell CD marker populations = Abs lymphocytes x % CD (as decimal).
For example:
AbsCD3 = 750 x 0.60 = 450 cells/mcL
AbsCD4 = 750 x 0.40 = 300 cells/mcL
AbsCD8 = 750 x 0.20 = 150 cells/mcL
CD4:CD8 ratio = 40/20 = 2.0