Impact of extremely low frequency electromagnetic fields on CD4 expressionin peripheral blood mononuclear cells

There is increasing evidence suggesting that extremely low frequency electr omagnetic fields (ELF-EMF) may influence several cell functions. Here the e ffects of ELF-EMF were studied on the expression of CD4(+) cell surface rec eptors of human peripheral blood mononuclear cells (PBMC) using florescence -activated cell sorter (FACScan). The expression of CD4(+) in ELF-EMF expos ed (24, 48 and 72 h) and not exposed PBMC were not statistically significan t. In addition, a flow cytometric analysis was determined by using a fluore scent labeled antibody, at 24 and 72 h incubations. The amount of bound ant ibody was distributed with a slight difference in the ELF-EMF-exposed PBMC compared to the not exposed cells. Moreover, DNA CD4(+) expression in PBMC strongly increased in exposed cells, resting and activated with Phytohaemag lutinin (PHA). When polymerase chain reaction was performed on CD4(+) mRNA of PBMC an increase of CD4(+) mRNA expression was found after the resting c ells were exposed to ELF-EMF at 24 h compared to not exposed cells, while a t 48 and 72 h no difference was found. In the cell cycle progression analys is, the PBMC exposed to ELF-EMF presented a significant increase of percent age expression of cell cycle progression in the S phase compared to not exp osed cells; while in G1 and G2 phases, there were no differences. Our resul ts provide new evidence that ELF-EMF can affect CD4(+) expression in PBMC a nd describe an additional biological activity for ELF-EMF affecting CD4(+) transcription and translation protein and the increase of the percentage ex pression of the cell cycle progression of the S phase.