manganese

Overview

Manganese is a chemical element with broad biological, environmental, and technological relevance. In biology and medicine, it is an essential trace metal that participates in enzyme function, redox chemistry, and metal-dependent signaling, but it can also be toxic when present in excess or in inappropriate chemical forms. Its divalent ion, Mn2+, is especially important in recent biomedical research because it can influence oxidative stress, immune signaling, and biomaterial performance.

In the studies summarized here, manganese was investigated primarily as a functional metal ion or material component rather than as a classical drug target. Recent work has explored Mn2+ in immune amplification strategies, nanoadjuvants, chemodynamic therapy, peptide metal binding, and environmental recovery systems. These applications reflect manganese’s ability to coordinate with biomaterials, modulate redox processes, and interact with pathways such as cGAS-STING and reactive oxygen species–linked antitumor immunity.

Recent Publications Summary

Recent studies have examined manganese as a functional component in immunotherapy, nanomedicine, imaging, and materials-based recovery systems. In several cancer-focused reports, Mn2+ was co-delivered with other stimuli to amplify innate immune signaling and improve antitumor responses. An mRNA lipid nanoparticle vaccine platform coencapsulating manganese with the STING agonist c-di-AMP and tumor antigen-encoding mRNA enhanced type I interferon signaling, costimulatory molecule expression, antigen presentation, and tumor-specific T cell responses 42418483Jul. Similarly, a photothermally triggered bacterial-metal immune amplifier used a manganese-tannic acid shell to enable on-demand Mn2+ release, lower the cGAS activation threshold, and hyper-activate the STING pathway, leading to dendritic cell maturation, CD8+ T cell recruitment, and systemic antitumor immunity in cold tumors 42029112Apr. A separate nanocatalytic platform based on manganese-in-situ-mineralized violet phosphorus nanosheets also leveraged Mn2+ to strengthen chemodynamic therapy, increase reactive oxygen species production, and potentiate STING-mediated antitumor immunity under NIR-II phototherapy 41330332Dec.

Manganese has also been incorporated into vaccine adjuvants and biomaterials to improve antigen delivery and immune activation. A sericin-chitosan nanoparticle loaded with Mn2+ served as a scalable nanoadjuvant for an inactivated pseudorabies virus vaccine, prolonging antigen release, improving antigen uptake by antigen-presenting cells, promoting dendritic cell maturation, and increasing CD4+/CD8+ T cell responses and memory T cells; the formulation also produced stronger humoral and Th1/Th2 cytokine responses than commercial adjuvants 41941907Apr. In another study, manganese was used in a boronic acid-modified Mn-porphyrin nanoparticle MRI contrast agent designed to evade macrophage uptake and improve lymph node metastasis diagnosis; boronic acid-functionalized particles showed reduced macrophage uptake in vitro and prolonged circulation in vivo 41666758Feb. Manganese was also evaluated in a pyrene-based manganese carbonyl complex that enabled green light-triggered carbon monoxide release and aggregation-induced emission, with the compound showing light-controlled CO liberation and cytotoxicity in SH-SY5Y cells 41579064Jan.

Beyond oncology and vaccination, manganese was investigated in coordination chemistry and analytical contexts. A glycopeptide study assessed binding of Cu2+ and Mn2+ to N- and O-glycosylated LL-37 fragments, finding that all peptides formed non-permanent complexes and that glycosylation reduced conformational flexibility while allowing occasional sugar-metal contacts 41780202Mar. In a metallomics study of long-term cryopreserved serum, manganese was among the metals quantified by ICP-MS, and its concentration differed significantly between long-term and short-term stored specimens alongside changes in the serum proteome 42348576Jun. Finally, manganese recovery from aqueous solutions was studied through ozone oxidative precipitation, where reaction conditions such as gas flow rate and temperature influenced Mn recovery and the process was interpreted using mass-transfer and precipitation kinetics 42233940Jun.

What Changes, What Holds

1. Mn2+ now looks like a programmable immune amplifier rather than only a general redox-active cofactor
NEW DIRECTION The new work extends the baseline by showing that manganese can be deliberately co-delivered to tune innate sensing, antigen presentation, and T-cell priming in cancer immunotherapy 42418483Jul42029112Apr41330332Dec. That fits the Overview’s cGAS-STING and reactive oxygen species framing, but it adds a more specific design role: Mn2+ is being used as an on-demand immune trigger inside nanoplatforms, not just as a biologically relevant metal ion.

2. Manganese is being developed as a practical adjuvant and imaging-material component, not only as a mechanistic immune modulator
NEW DIRECTION Sericin-chitosan loading and Mn-porphyrin engineering broaden the baseline from immune signaling to formulation science, vaccine delivery, and diagnostic materials 41941907Apr41666758Feb. The vaccine result reinforces manganese’s adjuvant potential, while the MRI work adds a separate materials-use case that the Overview does not cover. The carbonyl complex further shows light-controlled bioactivity, but that remains an early preclinical demonstration rather than a settled therapeutic role 41579064Jan.

3. Manganese binding and recovery are being characterized in ways that refine measurement and environmental handling rather than biological function
METHOD The glycopeptide, serum-metallomics, and ozone-precipitation studies do not change the established biological account of manganese; they change how manganese is analyzed, tracked, and recovered 41780202Mar42348576Jun42233940Jun. These papers sharpen coordination chemistry, storage effects, and process kinetics, but they mainly add methodological and analytical context. The serum work also warns that long-term specimen handling can alter measured manganese values, which matters for interpretation more than for manganese biology itself.