Nutritional Immunity in Wound Infection: Unveiling the Role of Dietary Elements in Host-Pathogen Interaction

Nutritional immunity is an essential defense process by which the host restricts the supply of critical micronutrients to invading pathogens, thus hindering their survival and growth. During wound infections, this mechanism is instrumental in determining the course of host-pathogen interactions. This article discusses the pathophysiology of wound infection, beginning with the classification of wounds as acute and chronic wounds, and emphasizes how compromised epithelial barriers and chronic inflammation provide a niche for microbial colonization. The host immune response during the healing of wounds is tightly regulated, with inflammatory mediators, neutrophil infiltration, macrophage polarization, and eventual tissue regeneration. However, in the case of normal pathogens like Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli, they exploit the microenvironment within the wound for accessing necessary nutrients while avoiding immune detection. The premise for this is nutritional immunity, where the host withholds metals like iron, zinc, manganese, and copper from access to prevent nutrient delivery to pathogens. Pathogens retaliate by generating siderophores, transporters, and metallophores to enable nutrient capture. In addition, clinical use of metal-chelating intelligent dressings, ionophore-antibiotic hybrids, and metal modulation technologies has improved our capability to control infection via nutritional routes. At the same time, immunonutrition with such nutrients as omega-3 fatty acids, arginine, glutamine, nucleotides, and antioxidant vitamins C and E has been demonstrated to have promise in promoting wound healing and maintaining immune resistance after surgery. This review emphasizes the necessity of targeting micronutrient pathways and incorporating nutritional immunity in wound care regimes for better clinical outcomes and prevention of infection-related complications.