Differential viability of eight human blood mononuclear cell subpopulations after plasma treatment

Abstract

In plasma medicine, basic and translational research aids in future application of cold plasma sources in human diseases or disorders (e.g., chronic wounds). While most work has focussed on the interaction of skin cells with plasma, immune system cells have only been marginally examined. Their role is of major importance because they fulfill key regulatory parts in immune responses and modulate inflammation in all types of tissues. This work systematically investigates eight different subpopulations (monocytes and CD4+, CD8+, B, NK, NKT, TH17, and γδ T cells) of human peripheral blood mononuclear cells with regard to viability after 5, 20, or 60 s of plasma treatment. Twenty-four hours after exposure, viability differed between populations (23.1% CD4+ versus 41.9% γδ T cells after 60 s of exposure) as revealed by flow cytometry. Cellular activation before plasma treatment increased survival in all subpopulations tested (26.8% in nonstimulated versus 50.0% in stimulated CD8+ T cells after 60 s of exposure). All lymphocyte subpopulations showed significantly (P < 0.05) lower survival rates compared to monocytes (35.9% for B cells versus 82.5% for monocytes after 60 s of exposure) but not compared to each other, hallmarking two intrinsically different coping types of cells regarding plasma cytotoxicity.