Targeted therapies of inflammatory diseases with intracellularly gelated macrophages in mice and rats

A cryo-shocked M2 macrophages based treatment strategy promoting repair of spinal cord injury via immunomodulation and axonal regeneration effects

Recovery from spinal cord injury (SCI) is often impeded by neuroinflammation, scar formation, and limited axonal regeneration. To tackle these issues, we developed an innovative biomimetic drug delivery system using liquid nitrogen-treated M2 macrophages (LNT M2) which internalized paclitaxel (PTX) nanoparticles beforehand. These were incorporated into a gelatin methacryloyl (GelMA) scaffold, creating a multifunctional, injectable treatment for single-dose administration. The LNT M2 inherited the inflammatory factor/chemokine receptors from the living M2 macrophages and thus possessing significant inflammatory neutralizing effect. In addition, the scaffold provides slow, sustained release of PTX, promoting axonal regeneration and suppressing scar formation in SCI rats. The LNT M2-based dual-functional scaffold significantly enhances motor function, reduces neuroinflammation, and accelerates axonal regeneration by modulating the inflammatory microenvironment and preventing the formation of glial and fibrotic scars. This approach combines the regenerative effects of low-dose PTX with the immunoregulatory properties of LNT M2, leading to remarkable neurological recovery in SCI rats. Moreover, the scaffold's straightforward preparation, ease of standardization, and "ready-to-use" nature make it a promising candidate for acute SCI intervention and future clinical applications.

Effects of microbial fermentation on the anti-inflammatory activity of Chinese yam polysaccharides

In this study, Chinese yam polysaccharides (CYPs) were fermented using Lactobacillus plantarum M616, and changes in the chemical composition, structure, and anti-inflammatory activity of CYPs before and after fermentation were investigated. The carbohydrate content of L. plantarum M616-fermented CYP (CYP-LP) increased from 71.03% ± 2.75 to 76.28% ± 2.37%, whereas protein and polyphenol content were almost unaffected compared with those of the unfermented CYP (CYP-NF). The monosaccharide composition of CYP-NF included rhamnose, arabinose, galactose, glucose, and mannose in a molar ratio of 0.493:0.6695:0.9738:0.7655:12.4365. CYP-LP had the same monosaccharides as CYP-NF, but the molar ratio was 0.3237:0.3457:0.8278:2.5541:10.4995. Meanwhile, the molecular weight and polydispersity of CYP-LP, respectively, increased from 124.774 kDa and 6.58 (CYP-NF) to 376.628 kDa and 17.928, indicating a low homogeneity. In vitro antioxidant analysis showed that L. plantarum M616 fermentation had varying effects on CYP-LP against DPPH, ABTS, hydroxyl, and superoxide radicals. However, CYP-LP had superior anti-inflammatory activity to CYP-NF and is more effective in regulating superoxide dismutase, catalase, glutathione peroxidase, malondialdehyde, nitric oxide, tumor necrosis factor-α, interleukin-1β, and interleukin-6 release in lipopolysaccharide-induced RAW 264.7 macrophages. This study suggested that CYP-LP is a potential anti-inflammatory ingredient in drugs and functional food.

Responsive Supramolecular Nanomicelles Formed through Self-Assembly of Acyclic Cucurbit[n]uril for Targeted Drug Delivery to Cancer Cells

The supramolecular drug delivery systems (SDDSs) based on host-guest recognition through noncovalent interactions, capable of responsive behavior and dynamic switching to external stimuli, have attracted considerable attention in cancer therapy. In this study, a targeted dual-functional drug delivery system was designed and synthesized. A hydrophilic macrocyclic host molecule (acyclic cucurbit[n]uril ACB) was modified with folic acid (FA) as a targeting ligand. The guest molecule consists of a disulfide bond attached to adamantane (DA) and cannabidiol (CBD) at both ends of the response element of glutathione. Recognition and self-assembly of host and guest molecules successfully functionalize supramolecular nanomicelles (SNMs), targeting cancer cells and releasing drugs in a high glutathione environment. The interactions between host and guest molecules were investigated by using nuclear magnetic resonance (NMR), fluorescence titration, Fourier-transform infrared spectroscopy (FT-IR), and thermal analysis (TGA). Transmission electron microscopy (TEM) and dynamic light scattering (DLS) confirmed the nanostructure of the SNMs. Experimentation with 5,5'-dithiobis (2-nitrobenzoic acid) (DTNB) demonstrated the responsiveness of SNMs to glutathione (GSH). In vitro cytotoxicity assays demonstrated that SNMs had a greater targeting efficacy for four types of cancer cells (HeLa, HCT-116, A549, and HepG2) compared to normal 293T cells. Cellular uptake studies revealed that HeLa cells more readily absorbed SNMs, leading to their accumulation in the tumor cell cytoplasm. Fluorescence colocalization assays verified that SNMs efficiently accumulated in organelles related to energy metabolism and signaling, including mitochondria and the endoplasmic reticulum, affecting cellular metabolic death. Both flow cytometry and confocal nuclear staining assays confirmed that SNMs effectively induced apoptosis over time, ultimately resulting in the death of cancer cells. These findings demonstrate that SNMs exhibit excellent targeting ability, responsiveness, high bioavailability, and stability, suggesting significant potential in drug delivery applications.

Dexamethasone-loaded ROS stimuli-responsive nanogels for topical ocular therapy of corneal neovascularization

Dexamethasone (DEX) has been demonstrated to inhibit the inflammatory corneal neovascularization (CNV). However, the therapeutic efficacy of DEX is limited by the poor bioavailability of conventional eye drops and the increased risk of hormonal glaucoma and cataract associated with prolonged and frequent usage. To address these limitations, we have developed a novel DEX-loaded, reactive oxygen species (ROS)-responsive, controlled-release nanogel, termed DEX@INHANGs. This advanced nanogel system is constructed by the formation of supramolecular host-guest complexes by cyclodextrin (CD) and adamantane (ADA) as a cross-linking force. The introduction of the ROS-responsive material, thioketal (TK), ensures the controlled release of DEX in response to oxidative stress, a characteristic of CNV. Furthermore, the nanogel's prolonged retention on the corneal surface for over 8 h is achieved through covalent binding of the integrin β1 fusion protein, which enhances its bioavailability. Cytotoxicity assays demonstrated that DEX@INHANGs was not notably toxic to human corneal epithelial cells (HCECs). Furthermore, DEX@INHANGs has been demonstrated to effectively inhibit angiogenesis in vitro. In a rabbit model with chemically burned eyes, the once-daily topical application of DEX@INHANGs was observed to effectively suppress CNV. These results collectively indicate that the nanomedicine formulation of DEX@INHANGs may offer a promising treatment option for CNV, offering significant advantages such as reduced dosing frequency and enhanced patient compliance.

Oral microsphere formulation of M2 macrophage-mimetic Janus nanomotor for targeted therapy of ulcerative colitis

Oral medication for ulcerative colitis (UC) is often hindered by challenges such as inadequate accumulation, limited penetration of mucus barriers, and the intricate task of mitigating excessive ROS and inflammatory cytokines. Here, we present a strategy involving sodium alginate microspheres (SAMs) incorporating M2 macrophage membrane (M2M)-coated Janus nanomotors (denominated as Motor@M2M) for targeted treatment of UC. SAM provides a protective barrier, ensuring that Motor@M2M withstands the harsh gastric milieu and exhibits controlled release. M2M enhances the targeting precision of nanomotors to inflammatory tissues and acts as a decoy for the neutralization of inflammatory cytokines. Catalytic decomposition of H2O2 by MnO2 in the oxidative microenvironment generates O2 bubbles, propelling Motor@M2M across the mucus barrier into inflamed colon tissues. Upon oral administration, Motor@M2M@SAM notably ameliorated UC severity, including inflammation mitigation, ROS scavenging, macrophage reprogramming, and restoration of the intestinal barrier and microbiota. Consequently, our investigation introduces a promising oral microsphere formulation of macrophage-biomimetic nanorobots, providing a promising approach for UC treatment.

The Prospect of Biomimetic Immune Cell Membrane-Coated Nanomedicines for Treatment of Serious Bacterial Infections and Sepsis

Invasive bacterial infections and sepsis are persistent global health concerns, complicated further by the escalating threat of antibiotic resistance. Over the past 40 years, collaborative endeavors to improve the diagnosis and critical care of septic patients have improved outcomes, yet grappling with the intricate immune dysfunction underlying the septic condition remains a formidable challenge. Anti-inflammatory interventions that exhibited promise in murine models failed to manifest consistent survival benefits in clinical studies through recent decades. Novel therapeutic approaches that target bacterial virulence factors, for example with monoclonal antibodies, aim to thwart pathogen-driven damage and restore an advantage to the immune system. A pioneering technology addressing this challenge is biomimetic nanoparticles-a therapeutic platform featuring nanoscale particles enveloped in natural cell membranes. Borne from the quest for a durable drug delivery system, the original red blood cell-coated nanoparticles showcased a broad capacity to absorb bacterial and environmental toxins from serum. Tailoring the membrane coating to immune cell sources imparts unique characteristics to the nanoparticles suitable for broader application in infectious disease. Their capacity to bind both inflammatory signals and virulence factors assembles the most promising sepsis therapies into a singular, pathogen-agnostic therapeutic. This review explores the ongoing work on immune cell-coated nanoparticle therapeutics for infection and sepsis. SIGNIFICANCE STATEMENT: Invasive bacterial infections and sepsis are a major global health problem made worse by expanding antibiotic resistance, meaning better treatment options are urgently needed. Biomimetic cell-membrane-coated nanoparticles are an innovative therapeutic platform that deploys a multifaceted mechanism to action to neutralize microbial virulence factors, capture endotoxins, and bind excessive host proinflammatory cytokines, seeking to reduce host tissue injury, aid in microbial clearance, and improve patient outcomes.

Walking Dead Macrophage-Based Positive Enhancement MRI for Ultrahighly Efficient Diagnosis of Nephritis

Nephritis is an inflammatory condition of the glomerulus, and the clinical gold standard for its diagnosis is a kidney biopsy. However, obtaining biopsy results can take several days, which does not meet the requirement of rapid diagnosis, especially for rapidly progressive types. To achieve an effective and noninvasive diagnosis, we propose a nephritis-specific, positive magnetic resonance imaging (MRI) contrast agent based on Gd3+ anchored walking dead macrophage Gd-RAW. Gd-RAW exhibits high selectivity for inflammatory renal parenchyma and provides comparable results to histopathology methods. The Gd-RAW-based MRI contrast agent reduces the diagnostic time of nephritis from 14 days of biopsy to 1 h. Furthermore, in a unilateral nephritis model constructed by increasing the glycerol concentration, the T1WI of renal parenchyma exhibits an increased signal-to-noise ratio, which is crucial for evaluating nephritic severity. This work promotes rapid diagnosis of nephritis and potentially provides sufficient evidence for clinicians to offer timely treatment to patients. The methodology of paramagnetic ion-anchored macrophage corpse also opens up new prospects for designing more specific and biosafe MRI contrast agents.

Macrophage membrane-camouflaged biomimetic nanovesicles for targeted treatment of arthritis

Arthritis has become the most common joint disease globally. Current attention has shifted towards preventing the disease and exploring pharmaceutical and surgical treatments for early-stage arthritis. M2 macrophages are known for their anti-inflammatory properties and their ability to support cartilage repair, offering relief from arthritis. Whereas, it remains a great challenge to promote the beneficial secretion of M2 macrophages to prevent the progression of arthritis. Therefore, it is warranted to investigate new strategies that could use the functions of M2 macrophages and enhance its therapeutic effects. This review aims to explore the macrophage cell membrane-coated biomimetic nanovesicles for targeted treatment of arthritis such as osteoarthritis (OA), rheumatoid arthritis (RA), and gouty arthritis (GA). Cell membrane-camouflaged biomimetic nanovesicle has attracted increasing attention, which successfully combine the advantages and properties of both cell membrane and delivered drug. We discuss the roles of macrophages in the pathophysiology and therapeutic targets of arthritis. Then, the common preparation strategies of macrophage membrane-coated nanovesicles are concluded. Moreover, we investigate the applications of macrophage cell membrane-camouflaged nanovesicles for arthritis, such as OA, RA, and GA. Taken together, macrophage cell membrane-camouflaged nanovesicles hold the tremendous prospect for biomedical applications in the targeted treatment of arthritis.