Monocyte contamination in Ficoll-Hypaque mononuclear cell concentrates

Area of Science:

• Immunology
• Cell Biology
• Hematology

Background:

• Mononuclear cell concentrates are crucial for various research and clinical applications.
• Ficoll-Hypaque (F-H) centrifugation is a common method for isolating mononuclear cells.
• Accurate assessment of monocyte contamination in these preparations is essential for reliable downstream applications.

Purpose of the Study:

• To evaluate the accuracy of different methods for quantifying monocyte contamination in F-H mononuclear concentrates.
• To compare morphological, functional, and cytochemical staining techniques for monocyte identification.
• To determine the most reliable method for assessing monocyte populations in F-H preparations.

Main Methods:

• Morphological assessment using Wright-Giemsa staining.
• Functional assessment via phagocytosis assays.
• Cytochemical staining for non-specific esterase, performed manually and by flow cytophotometry.
• Analysis of F-H preparations from 50 patient blood samples.

Main Results:

• Wright-Giemsa staining alone was insufficient for accurate monocyte quantitation.
• Monocyte counts obtained by flow cytophotometry of esterase-stained cells closely matched those from phagocytosis and manual cytochemical staining.
• Cytochemical staining and flow cytometry demonstrated high concordance with functional assays.

Conclusions:

• Manual Wright-Giemsa staining is inadequate for precise monocyte quantification in F-H concentrates.
• Cytochemical staining combined with flow cytometry provides a rapid and accurate method for assessing monocyte contamination.
• These advanced techniques ensure the quality and reliability of mononuclear cell preparations.