The MAGT1 transporter is critically involved in the selective regulation of intracellular free Mg2+ levels in mammalian cells. The molecular functions of free Mg2+ in eukaryotic cells have not been established. We found that patients with genetic deficiencies in MAGT1 have high levels of Epstein-Barr virus (EBV) and a predisposition to lymphoma. In studying lymphocytes from these patients, we found that a deficiency of MAGT1 caused decreased basal intracellular free Mg2+ leading to defective expression of the natural killer activating receptor NKG2D in NK and CD8+ T cells. Without NKG2D, cytolytic responses against EBV are diminished, thereby revealing the first specific molecular function of intracellular basal free Mg2+ in eukaryotic cells. Moreover, intracellular free Mg2+, NKG2D expression and function can be rescued in vitro by incubating patient cells and elevated levels of Mg2+. Moreover, NKG2D expression and cytolytic function can be improved and EBV-infected cells reduced in vivo, in MAGT1-deficient patients by magnesium administration. Thus, our data indicate an important molecular function for free basal Mg2+ in immunity and demonstrate a requirement for NKG2D cytolytic function in an essential EBV antiviral response in humans.

Project Start
Project End
Budget Start
Budget End
Support Year
1
Fiscal Year
2013
Total Cost
$418,961
Indirect Cost
City
State
Country
Zip Code
Juan, Ravell; Otim, Isaac; Nabalende, Hadijah et al. (2018) Plasma magnesium is inversely associated with Epstein-Barr virus load in peripheral blood and Burkitt lymphoma in Uganda. Cancer Epidemiol 52:70-74
Ozen, Ahmet; Comrie, William A; Ardy, Rico C et al. (2017) CD55 Deficiency, Early-Onset Protein-Losing Enteropathy, and Thrombosis. N Engl J Med 377:52-61
Abolhassani, Hassan; Edwards, Emily S J; Ikinciogullari, Aydan et al. (2017) Combined immunodeficiency and Epstein-Barr virus-induced B cell malignancy in humans with inherited CD70 deficiency. J Exp Med 214:91-106
Brigida, Immacolata; Chiriaco, Maria; Di Cesare, Silvia et al. (2017) Large Deletion of MAGT1 Gene in a Patient with Classic Kaposi Sarcoma, CD4 Lymphopenia, and EBV Infection. J Clin Immunol 37:32-35
Li, Feng-Yen; Chaigne-Delalande, Benjamin; Rao, V Koneti et al. (2015) Clinical utility gene card for: X-linked immunodeficiency with magnesium defect, Epstein-Barr virus infection, and neoplasia (XMEN). Eur J Hum Genet 23:
Ravell, Juan; Chaigne-Delalande, Benjamin; Lenardo, Michael (2014) X-linked immunodeficiency with magnesium defect, Epstein-Barr virus infection, and neoplasia disease: a combined immune deficiency with magnesium defect. Curr Opin Pediatr 26:713-9
Chaigne-Delalande, Benjamin; Lenardo, Michael J (2014) Divalent cation signaling in immune cells. Trends Immunol 35:332-44
Li, Feng-Yen; Chaigne-Delalande, Benjamin; Su, Helen et al. (2014) XMEN disease: a new primary immunodeficiency affecting Mg2+ regulation of immunity against Epstein-Barr virus. Blood 123:2148-52
Chaigne-Delalande, Benjamin; Li, Feng-Yen; O'Connor, Geraldine M et al. (2013) Mg2+ regulates cytotoxic functions of NK and CD8 T cells in chronic EBV infection through NKG2D. Science 341:186-91
Lo, Bernice; Ramaswamy, Madhu; Davis, Joie et al. (2013) A rapid ex vivo clinical diagnostic assay for fas receptor-induced T lymphocyte apoptosis. J Clin Immunol 33:479-88

Showing the most recent 10 out of 14 publications