Iron, Copper, and Zinc Homeostasis in the Battle between Macrophage and Mycobacterium Tuberculosis

Abstract: Iron, copper, and zinc play integral roles in the battle against Mycobacterium tuberculosis (Mtb) infection; however, they are often trapped between nutrients and toxins, posing a significant challenge to macrophages and Mtb to utilize them. Due to this two-sided effect, macrophages and Mtb strictly regulate metal uptake, storage, and excretion. This review discusses the balanced regulation of iron, copper, and zinc in macrophages and Mtb during infection, focusing on the intracellular metal regulatory system. Macrophages typically use the two-sided effect of metals to limit Mtb access to nutrients or poison them. Mtb has developed a metal metabolism regulatory mechanism compatible with the nutritional immune strategy. This includes the mediation of relevant metalloproteins and metalloenzymes to maintain the multimetal balance. This review also explored the regulation of metal metabolism homeostasis in macrophages resistant to Mtb infection, providing a theoretical foundation for identifying potential clinical targets for Mtb infection, developing metalloid anti-tuberculosis drugs, and understanding the immune mechanisms against intracellular Mtb infection.