Problems of Radiation Medicine and Radiobiology

Bazyka D. A., Kubashko A. V., Ilyenko I. M., Belyaev O. A., Pleskach O. J.

Expression of Cyclin d1 protein and CCND1 та PNKP genes in peripheral blood mononuclear cells in clean-up worker of Chornobyl accident with different state of immune system

Objective: to investigate the Cyclin D1+ cells levels changes, associated CCND1 and PNKP genes in peripheral blood mononuclear cells in clean-up workers of Chornobyl accident with different state of immune system in depends on the dose irradiation.
Material and methods. Relative level of Cyclin D1+cells in peripheral blood mononuclears of 39 clean-up workers, men, irradiated in dose range (0,01–2,00) Gy have been analyzed. Immunological status of examinee’ subjects was determined by CD3/19, CD4/8, CD3/HLA-DR, СD3/16/56 testing using flow cytometry method and Ig A, M, G testing by immunoenzymatic assay in blood. CCND1 та PNKP gene expression, which associated with Cyclin D1 metabolism, was conducted using PCR real time method. The obtained results were compared in relation to data from 18 healthy men, who had no contact with ionizing radiation over then nature background.
Results. Аnalyzed data of the nuclear controller of cell cycle – Cyclin D1 protein expression changes and related CCND1 та PNKP genes in peripheral blood mononuclear cells in clean-up workers Chornobyl accident with different status of immune system in remote period after exposure is represented. It is shown, that in examinees’ subjects exposed in dose > 0,1 Gy percentage of Суclin D1+ cells is elevated against normal range and correlates with dose of radiation (rs = 0.417, p = 0.048). Normal range deflation of  relative amount of Cyclin D1+cells connects with changes in cellular and humoral immunity. Decline of relative amount of Cyclin D1+ cells below the control level following CD3+ lymphocytes decrease and  CD3-16+56+ elevation in clean-up workers exposed in dose < 0.35 Gy. Increase of relative amount of Cyclin D1+ cells above the control range associates with CD3+ fall together with tendency of CD3+16+56+ lymphocytes fall that attends the IgG elevation in examinees’ subjects with dose > 0.35 Gy. Percentage of Cyclin D1+ cells correlates with CD3-16+56+ (rs = -0.872, p = 0,049), CD8+ and IgG (rs = 0.683, p = 0.042; rs = 0.809, p = 0.014), CD4+ (rs = 0.602, p = 0.029), CD19+ and IgM  (rs = 0.604, p = 0.017; rs = 0.538, p = 0.038) under condition of increased level CD4+, CD19+, Іreg. and IgG accordantly. Reviled decrease the CCND1 and PNKP gene expression in clean-up workers exposed in dose > 0.1 Gy following appearance of correlation between (relative quantification) RQ PNKP and irradiation dose (rs = -0.638, p = 0.035) and also with RQ PNKP and percentage of Cyclin D1+ cells (rs = -0.792, p = 0.034).
Concusions. Reveled changes in expression of Cyclin D1+ cells and regulation of related genes may point on possible radiation-associated firm molecular disturbances occurred during elimination of consequences of Chornobyl accident, that could be a potential basis for cell and humoral communicative links breach in immune system resulting in elevation of stochastic effects like oncopathology in clean-up workers of Chornobyl accident in remote period after exposure.

Key words: Cyclin D1, CCND1 and PNKP gene expression, cell and humoral immunity, clean-up workers of Chornobyl accident.

Problems of radiation medicine and radiobiology. 2015;20:269–282.