Calcium uptake by leukemic and normal T-lymphocytes exposed to low frequency magnetic fields.

Calcium-ion uptake by normal and leukemia lymphocytes increased during a 30-min exposure to a 13.6 Hz, sinusoidal magnetic field at 20 microT peak. The time-varying field was horizontal and parallel to a 16.5 microT component of the ambient static magnetic field. The uptake of 45Ca2+ increased 102% in a line of murine, cytotoxic T-lymphocytes (C57B1/6-derived CTLL-1), increased 126% in freshly-isolated spleen lymphocytes (C57B1/6 mice), and increased 75% in a line of lymphoma cells (C57B1/6-derived EL4). In contrast, there was no effect when the same field was applied for 30 min immediately before--as opposed to during--incorporation of calcium ions. When spleen lymphocytes were exposed during incubation with 45Ca2+ to a 60 Hz magnetic field at 20 microT peak, a small but statistically significant increase (37%) in uptake of the labeled ions occurred. These results indicate that weak, alternating magnetic fields might affect calcium-dependent functions of normal and leukemic lymphocytes.