Magnesium content and concentration of mononuclear and T lymphocyte blood cells

The magnesium content of mononuclear blood cells (MBCs) may be a better indicator of intracellular or total body Mg status than either serum or red blood cell Mg. However, MBCs are a heterogeneous population composed primarily of lymphocytes and monocytes. A significant difference in the Mg concentration or content between lymphocytes and monocytes could alter the results for MBC Mg. We produced monocyte-poor MBCs (MPMBCs) by treating MBCs with carbonyl iron particles. We purified T lymphocytes from MPMBCs [antihuman F(ab)2 monolayer procedure]. The purity of T lymphocytes (T + NK cells) was 98% by flow-cytometric analysis. The mean (+/- SEM) Mg content and concentration of MPMBCs were 61.9 +/- 3.0 fg/cell and 10.6 +/- 0.4 mmol/l, respectively, and of T lymphocytes 60.8 +/- 2.7 fg/cell and 11.8 +/- 0.4 mmol/l, respectively. There was no significant difference in Mg content between MPMBCs and T lymphocytes. The Mg concentration of T lymphocytes was significantly higher (p less than 0.001) than MPMBCs. However, the difference is small and does not justify the increased complexity of the assay for T lymphocytes. We conclude that the cell composition of MBCs may affect the result for Mg concentration.