Jurkat E6-1 cells obtained from three different sources were compared with respect to intracellular calcium response to a 50Hz, 0.15mT, magnetic field, to treatment with poly-l-lysine and to protein expression at the cell surface. The fura-2 single cell measurements were a replication study performed by three members of our group. The cells responded to the applied magnetic fields, although the percentage of responding cells was lower than in earlier studies. The geomagnetic field was backed off without changing the outcome of the intracellular calcium measurements. Fluorometric analyses showed no difference between the E6-1 cells obtained from three sources with respect to the expression of cell surface marker molecules. The addition of the cell adhesive peptide, poly-l-lysine, did not itself cause any effects on the intracellular calcium concentration.