Orally Administrable Aggregation-Induced Emission-Based Bionic Probe for Imaging and Ameliorating Dextran Sulfate Sodium-Induced Inflammatory Bowel Diseases

Macrophage-Tased Dual-Phase T Cell Immunomodulation to Combat Transplant Rejection

Transplant rejection remains a major challenge, driven primarily by the activation of alloreactive T cells. While enhancement of PD-L1 checkpoint molecules has exhibited potential in inhibiting T cell activity, its efficacy is often hindered by limited specificity and inadequate efficiency. Herein, a novel dual-phase immune modulation strategy is developed in which CTLA4-Ig and PD-L1 provide distinct, non-redundant inhibitory signals during the initial activation phase and the post-activation phase of T cells. PD-L1 is stably expressed on macrophages (sPD-L1 M) through lentiviral transduction, allowing them to leverage their chemotactic and antigen-presenting functions to target and deliver PD-L1 to transplant rejection sites. Notably, sPD-L1 M exhibited adaptive targeting capabilities, increasing their migration to grafts in response to heightened rejection. In an allograft skin model, the combined intravenous administration of sPD-L1 M and subcutaneous administration of CTLA4-Ig demonstrated synergistic efficacy, significantly suppressing alloreactive T cell activation, enhancing the recruitment of regulatory T cells (Tregs), downregulating pro-inflammatory cytokines, and prolonging allograft survival compared to either treatment alone. This study presents a promising strategy to effectively suppress T cell activity and prevent allogeneic immune responses without systemic immunosuppression.

Application of aggregation-induced emission materials in gastrointestinal diseases

Aggregation-induced emission (AIE) is a phenomenon characterized by certain fluorescent molecules that exhibit weak or no luminescence in solution but demonstrate significantly enhanced luminescence upon aggregation. Accordingly, AIE materials have successfully addressed the limitations associated with aggregation-caused quenching effects and have made significant progress in the application of various fields of medicine in recent years. At present, the application of AIE materials in gastrointestinal (GI) diseases is mainly in GI imaging, diagnosis and treatment. In this review, we summarize the applications of AIE materials in GI pathogens and GI diseases, including inflammatory bowel disease and GI tumors, and outline combined treatment methods of AIE materials in GI tumor therapy.

PepT1-targeted nanodrug based on co-assembly of anti-inflammatory peptide and immunosuppressant for combined treatment of acute and chronic DSS-induced ColitiS

INTRODUCTION

Inflammatory bowel disease (IBD), as a chronic and recurrent inflammatory bowel diseases with limited therapeutic outcomes, is characterized by immune disorders and intestinal barrier dysfunction. Currently, the most medications used to cure IBD in clinic just temporarily induce and maintain remission with poor response rates and limited outcomes. Therefore, it is urgently necessary to develop an appropriate therapeutic candidate with preferable efficacy and less adverse reaction for curing IBD.

METHODS

Five groups of mice were utilized: control that received saline, DSS group (mice received 2.5% DSS or 4% DSS), KPV group (mice received KPV), FK506 group (mice received FK506) and NPs groups (mice received NPs). The effect of NP on the inflammatory factors of macrophage was evaluated using CCK-8, quantitative polymerase chain reaction (PCR), Elisa and Western blot (WB). Immunofluorescent staining revealed the targeting relationship between NP and Petp-1. Immunohistochemistry staining showed the effect of NP on tight junction proteins. Moreover, in vivo animal experiments confirmed that NPs reduced inflammatory levels in IBD.

RESULTS AND DISCUSSION

After administering with NPs, mice with DSS-induced acute or chronic colitis exhibited significant improvement in body weight, colon length, and disease activity index, decreased the level of the factors associated with oxidative stress (MPO, NO and ROS) and the inflammatory cytokines (TNF-α, IL-1β and IL-6), which implied that NPs could ameliorate murine colitis effectively. Furthermore, treating by NPs revealed a notable reduction of the expressions of CD68 and CD3, restoring the expression levels of tight junction proteins (Claudin-5, Occludin-1, and ZO-1) were significantly restored, surpassing those observed in the KPV and FK506 groups. which indicated that NPs can reduce inflammation and enhance epithelial barrier integrity by decreasing the infiltration of macrophages and T-lymphocytes. Collectively, those results demonstrated the effectively therapeutic outcome after using NPs in both acute and chronic colitis, suggesting that the newly co-assembled of NPs can be as a potential therapeutic candidate for colitis.

Nanoparticle-Mediated Multiple Modulation of Bone Microenvironment To Tackle Osteoarthritis

Development of nanomedicines that can collaboratively scavenge reactive oxygen species (ROS) and inhibit inflammatory cytokines, along with osteogenesis promotion, is essential for efficient osteoarthritis (OA) treatment. Herein, we report the design of a ROS-responsive nanomedicine formulation based on fibronectin (FN)-coated polymer nanoparticles (NPs) loaded with azabisdimethylphoaphonate-terminated phosphorus dendrimers (G4-TBP). The constructed G4-TBP NPs-FN with a size of 268 nm are stable under physiological conditions, can be specifically taken up by macrophages through the FN-mediated targeting, and can be dissociated in the oxidative inflammatory microenvironment. The G4-TBP NPs-FN loaded with G4-TBP dendrimer having intrinsic anti-inflammatory property and FN having both anti-inflammatory and antioxidative properties display integrated functions of ROS scavenging, hypoxia attenuation, and macrophage M2 polarization, thus protecting macrophages from apoptosis and creating designed bone immune microenvironment for stem cell osteogenic differentiation. These characteristics of the G4-TBP NPs-FN lead to their effective treatment of an OA model in vivo to reduce pathological changes of joints including synovitis inhibition and cartilage matrix degradation and simultaneously promote osteogenic differentiation for bone repair. The developed nanomedicine formulation combining the advantages of both bioactive phosphorus dendrimers and FN to treat OA may be developed for immunomodulatory therapy of different inflammatory diseases.

Designing self-triggered micro/milli devices for gastrointestinal tract drug delivery

INTRODUCTION

Self-triggered micro-/milli-devices (STMDs), which are artificial devices capable of responding to the surrounding environment and transferring external energy into kinetic energy, thus realizing autonomous movement, have come to the forefront as a powerful tool in cargo delivery via gastrointestinal tract. Urgent needs have been raised to overview the development of this area.

AREAS COVERED

We summarize the advancement of designing STMDs for delivery via gastrointestinal tract. We first give a brief overview on the opportunities and challenges of delivery via gastrointestinal tract involving gastric barriers and intestinal barriers. Then, emphasis is laid on the design and applications of STMDs for delivery via gastrointestinal tract. We focus on their morphological characteristics and function design, expounding their working mechanisms in the complex gastrointestinal tract.

EXPERT OPINION

Although with much progress in STMDs, there is still a huge gap between laboratory researches and clinical applications due to some limitations including latent digestive burden, sophisticated fabrication, unstable delivery, and so on. We give a discussion on the potential, challenges, and prospects of developing STMDs for delivery via gastrointestinal tract.