Study on the effect of polyhydroxylated fullerene, C60(OH)36, on X-ray irradiated human peripheral blood mononuclear cells

• C60(OH)36 increases viability of X-irradiated human peripheral blood lymphocytes.
• Fullerenol enhances lymphocytes granularity without causing cytotoxicity.
• C60(OH)36 interacts with the surface of plasma membrane but not inside PBMCs.
• The effects of C60(OH)36 on X-irradiated human PBMCs are very small.

The effect of polyhydroxylated fullerene (fullerenol), C60(OH)36, on human peripheral blood mononuclear cells (PBMCs) exposed to X-rays was studied. PBMCs untreated and treated for 1 h with C60(OH)36 at the concentrations 75 and 150 mg/l were exposed to high doses of ionizing radiation (10, 30 and 50 Gy). After 24 and 48 h of post-irradiation incubation the viability and granularity of lymphocytes were determined applying the flow cytometry (FC) method. Moreover, after 24 h of incubation the membrane fluidity was investigated by measuring the fluorescence anisotropy of a 1,6-diphenyl-1,3,5-hexatriene (DPH) probe. Additionally, DNA damage of PBMCs after exposure to X-rays at the doses 0, 5, 10 and 15 Gy in the absence and presence of fullerenol (75 mg/l) was determined using the comet assay under alkaline conditions. Results show that the effects of fullerenol C60(OH)36 on X-irradiated human PBMCs are very small or inexistent. It was suggested that this action of C60(OH)36 may be related to its interactions with the surface of plasma membrane but not inside PBMCs.