Nutritional immunity: the impact of metals on lung immune cells and the airway microbiome during chronic respiratory disease

Abstract

Nutritional immunity is the sequestration of bioavailable trace metals such as iron, zinc and copper by the host to limit pathogenicity by invading microorganisms. As one of the most conserved activities of the innate immune system, limiting the availability of free trace metals by cells of the immune system serves not only to conceal these vital nutrients from invading bacteria but also operates to tightly regulate host immune cell responses and function. In the setting of chronic lung disease, the regulation of trace metals by the host is often disrupted, leading to the altered availability of these nutrients to commensal and invading opportunistic pathogenic microbes. Similarly, alterations in the uptake, secretion, turnover and redox activity of these vitally important metals has significant repercussions for immune cell function including the response to and resolution of infection. This review will discuss the intricate role of nutritional immunity in host immune cells of the lung and how changes in this fundamental process as a result of chronic lung disease may alter the airway microbiome, disease progression and the response to infection.

Recent Advances in Fungal Infections: From Lung Ecology to Therapeutic Strategies With a Focus on Aspergillus spp.

“…Indeed, non-siderophore producing bacteria are known to steal other species’ siderophores through the use of a matching receptor ( 240 ). On the other hand, host cells internalize iron through a global process called nutritional immunity, aimed at controlling infection ( 241 , 242 ). However, unlike for the gut microbiota ( 243 ), the interplay between the regular members of the airway microbiota and nutritional immunity is still largely undetermined.…”

“…However, unlike for the gut microbiota ( 243 ), the interplay between the regular members of the airway microbiota and nutritional immunity is still largely undetermined. Indeed, while essential metals, such as iron or zinc, have been found to be altered in several respiratory diseases, the exact causes and mechanistic consequences of this metal dysregulation on the immune system and respiratory microbiota still need to be further explored ( 242 ). Interestingly, gallium, a group IIIA metal, has been proposed as an antifungal agent.…”

Effective Regulation of Gut Microbiota With Probiotics and Prebiotics May Prevent or Alleviate COVID-19 Through the Gut-Lung Axis

“…The lung and airway microbiome directly affect immunity to disease and can change local immunity/inflammation during disease progression ( Healy et al, 2021 ). RTI virus infection can directly cause immune damage to the respiratory tract and intestinal mucosa ( Gautier et al, 2021 ).…”

Potential for Further Mismanagement of Fever During COVID-19 Pandemic: Possible Causes and Impacts

“…Incidentally, robust HSR generation is suppressed in most of the COVID-19 comorbid conditions, e.g., cardiovascular diseases, obesity, frailty, diabetes, and metabolic syndromes (58). Protective alterations in essential metal ions levels are made in different internal milieus (nutritional immunity) during the acute-phase response (59)(60)(61)(62). For example, reduced serum zinc levels protect the host tissues from oxidative damage and enhance the chemotaxis and immune cells' activity, such as the targeted intracellular pathogen killing (63)(64)(65).…”