Culture of lymphocytes from humans in Mg-deficient media, resulted in morphologically and functionally abnormal cells. Magnesium really is everywhere in the body – it’s the 4th most abundant mineral. It’s involved in hundreds of different biochemical reactions and enzyme systems and is crucial for proper immune system function. Mg has a strong relation with the immune system, in both nonspecific and specific immune response, also known as innate and acquired immune response.
Mg participates in immune responses in numerous ways: as a cofactor for immunoglobulin synthesis, C'3 convertase, immune cell adherence, antibody dependent cytolysis, IgM lymphocyte binding, macrophage response to lymphokines, T helper-B cell adherence, binding of substance P to lymphoblasts and antigen binding to macrophage RNA. Mg deficiency in rodents impairs IgG synthesis and cell-mediated immunity; complications include thymus atrophy, elevated IgE, hypereosinophilia, histaminosis and lymphoma.
 Magnesium. 1988;7(5-6):290-9. Magnesium and immune function: an overview. Galland L.