Frozen Cord Blood PT Program - AP, Fall

A proficiency testing program from STEMCELL Technologies enables laboratories to benchmark colony-forming unit (CFU) assay performance using frozen human cord blood samples. Participants receive a kit containing frozen cord blood mononuclear cells, MethoCult™ semi-solid culture medium, Iscove's MDM with 2% FBS, a dry goods kit, and a session-specific information letter, with results submitted for cohort statistical analysis.

Frozen components are shipped on dry ice and stored according to specific conditions: the cell component at -135°C or colder, MethoCult™ and Iscove's MDM at -20°C, and the dry goods kit at room temperature (15-25°C). The session-specific information letter provides the 10X Plating Density for the cohort.

In the assay workflow, cells are thawed in a 37°C water bath, washed, and counted to determine nucleated cell concentration and viability. The cell stock is diluted to the 10X Plating Density in Iscove's MDM with 2% FBS, then combined with MethoCult™ and plated into 35 mm culture dishes. Four replicates are prepared for statistical analysis. Dishes are incubated at 37°C, 5% CO₂, and ≥95% humidity for 14 days, after which colonies are enumerated. Data is submitted through online forms, email, or a completed worksheet. Supporting resources include the Technical Manual for Human Colony-Forming Unit (CFU) Assays Using MethoCult™ and the Atlas of Hematopoietic Colonies From Cord Blood.