Monocytes isolated by positive and negative magnetic sorting techniques show different molecular characteristics and...

Area of Science:

• Immunology
• Cell Biology

Background:

• Immunomagnetic cell separation uses microbead-conjugated antibodies for isolating specific cell populations.
• Positive selection attaches microbeads to target cells, while negative selection targets non-target cells.

Purpose of the Study:

• To compare the effects of positive and negative immunomagnetic selection on the functional and immunophenotypic behavior of isolated CD14+ monocytes.
• To assess the impact of microbead attachment on monocyte activation, proliferation, and LPS sensitivity.

Main Methods:

• Peripheral blood mononuclear cells (PBMCs) were isolated from healthy volunteers.
• CD14+ monocytes were isolated using both positive and negative selection kits.
• Isolated monocytes were stimulated with lipopolysaccharide (LPS), and their activation, proliferation, and microbead dissociation were examined.

Main Results:

• Positively sorted CD14+ monocytes exhibited impaired LPS sensitivity, activation, and proliferation compared to negatively sorted cells.
• Microbeads remained attached to cells and did not degrade even after 6 days of culture.
• Negatively sorted monocytes showed preserved functional capacity.

Conclusions:

• Positive immunomagnetic sorting of CD14+ monocytes can lead to hampered functionality, potentially causing inaccuracies in downstream applications.
• Negative selection preserves monocyte function, making it more suitable for studies requiring functional integrity.
• Positively sorted cells may be suitable for immediate analytical procedures where functional impairment is not a concern.