Reported changes in the cytosolic calcium concentration ([Ca2+](c)) as a result of exposure to extremely low frequency (ELF) magnetic fields (MF) have been equivocal. In this study, we examine the possibility that some of these differences are attributable to variability associated with the cell cycle, pH of the suspension medium, and response to a calcium agonist. We used a custom designed spectrofluorimeter to measure [Ca2+](c) in Indo 1-AM loaded Jurkat E6.1 cells suspended in conditioned RPMI 1640 medium containing 10% fetal bovine serum. Four exposures were examined: zero static MF (Null), 60 Hz 100 microT(peak) sinusoidal MF (AC), 78 microT static MF (DC), and the combination of the 60 Hz and the 78 microT static MF (AD + DC). A significant decrease in normalized [Ca2+](c) values between 375-495 s for the DC and AC + DC groups was found in comparison to the Null group. However, statistical analysis indicated that cell cycle and quality of the alpha-CD3 monoclonal antibody response were significant covariates, while pH was not a significant covariate. When the effect of these covariates was taken into account, all exposure groups were significantly different from the control. Our results suggest that ELF MF effects may not be seen unless correction is made for biological variability of each cell preparation with respect to cell cycle and [Ca2+](c) response to antigen stimulation.

中文翻译：

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暴露于ELF磁场期间，Jurkat E6.1细胞中胞质钙测量值混杂的因素。

暴露于极低频（ELF）磁场（MF）导致胞质钙浓度（[Ca2 +]（c））的变化报道是模棱两可的。在这项研究中，我们检查了这些差异中的一些归因于与细胞周期，悬浮培养基的pH值以及对钙激动剂的反应有关的可变性的可能性。我们使用了定制设计的荧光分光光度计来测量悬浮在含有10％胎牛血清的条件RPMI 1640培养基中的印加1-AM的Jurkat E6.1细胞中的[Ca2 +]（c）。检查了四次曝光：零静态MF（零），60 Hz 100 microT（峰值）正弦MF（AC），78 microT静态MF（DC）以及60 Hz和78 microT静态MF（AD + DC）的组合）。与Null组相比，DC和AC + DC组在375-495 s之间的归一化[Ca2 +]（c）值显着降低。然而，统计分析表明，细胞周期和α-CD3单克隆抗体反应的质量是显着的协变量，而pH并不是显着的协变量。当考虑这些协变量的影响时，所有暴露组均与对照组显着不同。我们的结果表明，除非对每种细胞制备物的细胞周期和对抗原刺激的[Ca2 +]（c）反应的生物学变异性进行校正，否则可能无法看到ELF MF效应。而pH值不是显着的协变量。当考虑这些协变量的影响时，所有暴露组均与对照组显着不同。我们的结果表明，除非对每种细胞制备物的细胞周期和对抗原刺激的[Ca2 +]（c）反应的生物学变异性进行校正，否则可能看不到ELF MF效应。而pH值不是显着的协变量。当考虑这些协变量的影响时，所有暴露组均与对照组显着不同。我们的结果表明，除非对每种细胞制备物的细胞周期和对抗原刺激的[Ca2 +]（c）反应的生物学变异性进行校正，否则可能看不到ELF MF效应。