Immune Recharge wayds Glutathione for Dogs Maxx Life 30ct Earth Buddy Earth Buddy Pet 1. Immune Defense at the Cellular Level Zinc and Vitamin C are foundational for immune cell signaling and response, while glutathione supports intracellular defense mechanisms. Together, they help the body stay resilient Antioxidant Functions of Vitamin D and CYP11A1 Derived Vitamin D, Tachysterol, and Lumisterol Metabolites: Mechanisms, Clinical Implications, and Future Directions