title: Magnesium counteracts nickel-induced suppression of T lymphocyte response to concanavalin A.
abstract: Effects of nickel and magnesium on the responsiveness of BALB/c mouse spleen lymphocytes to a mitogen, concanavalin A (Con A), were studied using the in vitro 3H-thymidine (TdR) incorporation test. Nickel chloride (NiCl2) and nickel subsulfide (Ni3S2) were found to suppress this response. The control level of TdR incorporation from a magnesium-free medium containing 0.625 microgram Con A/ml into trichloroacetic-acid-precipitable nucleoprotein was depressed by both nickel compounds in a dose-dependent manner to 3% of its original value by 0.25 mumol NiCl2/ml or 0.33 mumol Ni3S2/ml (5 micron particles). Magnesium stimulated TdR incorporation up to a maximum of 200% of the control level at concentrations greater than 2.0 mumol MgCl2/ml. Also, gradual increase of magnesium concentration in the culture medium up to 2.0 mumol/ml attenuated the effects of nickel, restoring the lymphocyte response to Con A to 43% of the control level at 0.25 mumol NiCl2/ml or to 30% at 0.33 mumol Ni3S2/ml. Higher concentrations of magnesium did not further enhance this responsiveness. These data suggest that the effect of magnesium upon early cellular response to nickel observed in vivo [Kasprzak et al.: Carcinogenesis 6: 1161-1166, 1985], which eventually results in a decreased tumor incidence, may be due in part to antagonism by magnesium of nickel suppression of the activity of T lymphocytes.
authors.affiliation: Inorganic Carcinogenesis Section, National Cancer Institute, Frederick, Md.
authors.forename: K S
authors.initials: KS
authors.lastname: Kasprzak
authors.forename: R F
authors.initials: RF
authors.lastname: Kiser
authors.forename: O S
authors.initials: OS
authors.lastname: Weislow
mesh_terms: D000818:Animals; D003208:Concanavalin A / Q000494:pharmacology*; D004247:DNA / Q000096:biosynthesis; D004347:Drug Interactions; D005260:Female; D008274:Magnesium / Q000494:pharmacology*; D051379:Mice; D008807:Mice, Inbred BALB C; D009532:Nickel / Q000494:pharmacology*; D013154:Spleen / Q000166:cytology; D013601:T-Lymphocytes / Q000187:drug effects* / Q000378:metabolism
chemical_list: C005479:magnesium carbonate; D003208:Concanavalin A; C022838:nickel chloride; D009532:Nickel; D004247:DNA; D008274:Magnesium; C017557:nickel subsulfide