OX40L blockade cellular nanovesicles for autoimmune diseases therapy

Engineered Cell Membrane Vesicles Expressing CD40 Alleviate System Lupus Nephritis by Intervening B Cell Activation

Immune intervention of B cell activation to blockade the production of autoantibodies provokes intense interest in the field of systemic lupus erythematosus (SLE) therapy development. Although the survival rate for SLE is improved, many patients die untimely. Engineered cell membrane vesicles manifest remarkable capacity of targeted drug delivery and immunomodulation of immune cells such as B cells. Herein, this work engineered cellular nanovesicles (NVs) presenting CD40 (CD40 NVs) that can blunt B cells and thus alleviate SLE. CD40 NVs disrupt the CD40/CD40 ligand (CD40L) costimulatory signal axis through the blockade of CD40L on CD4⁺ T cells. Therefore, the CD40 NVs restrain the generation of the germinal center structure and production of antibodies from B cells. Furthermore, immunosuppressive drug mycophenolate mofetil (MMF) is also encapsulated in the vesicles (MMF-CD40 NVs), which is employed to deplete immunocytes including B cells, T cells, and dendritic cells. Together, CD40 NVs are promising formulations for relieving autoimmunity and lupus nephritis in MRL/lpr mice.

Sponge-like nano-system suppresses tumor recurrence and metastasis by restraining myeloid-derived suppressor cells-mediated immunosuppression and formation of pre-metastatic niche

Tumor recurrence and metastasis still greatly limit the therapeutic efficiency on the majority of postoperative clinical cases. With the aim to realize more powerful treatment outcomes on postoperative malignant tumors, a sponge-like neutrophil membrane-coated nano-system (NM/PPcDG/D) was fabricated to inhibit tumor recurrence and metastasis by inhibiting the recruitment and functions of myeloid-derived suppressor cell (MDSCs), which reinforced anti-tumor immunity and also suppressed pulmonary metastasis by inhibiting the formation of pre-metastatic niche (PMN). Firstly, PPcDG/D nanoparticles (NPs) were formulated by the self-assembling and crosslinking of synthesized redox-responsive polymer (PPDG) with doxorubicin (DOX) loading in the nanocore (PPcDG/D), followed by coating with activated neutrophils membrane to fabricate biomimetic NM/PPcDG/D. The sponge-like NM/PPcDG/D not only showed obvious natural tropism to postoperative inflammatory site, but also inhibited the recruitment and functions of MDSCs, thus relieved MDSCs-mediated immunosuppression. Additionally, NM/PPcDG/D also suppressed the formation of PMN to inhibit pulmonary metastasis by reducing the recruitment of MDSCs, decreasing the permeability of pulmonary vessels and inhibiting the implantation of circulating tumor cell (CTCs). Eventually, this fabricated NM/PPcDG/D NPs significantly inhibited tumor recurrence and metastasis on postoperative triple negative breast cancer (TNBC) model, presenting a promising therapeutic strategy on postoperative malignant tumors. STATEMENT OF SIGNIFICANCE: Myeloid-derived suppressor cells (MDSCs) play important roles in accelerating tumor recurrence and metastasis by promoting the establishment of immunosuppression in postoperative inflammatory regions and facilitating the formation of pulmonary pre-metastasis niche (PMN). In order to achieve enhanced suppression of recurrence and metastasis, a sponge-like NM/PPcDG/D nano-system was designed and fabricated. This nano-system is also the first attempt to integrate the regulation effects of a nano-sponge and anti-inflammatory agent to achieve enhanced multi-mode manipulation of MDSCs. Ultimately, NM/PPcDG/D powerfully restrained the recurrence and spontaneous metastasis on TNBC model. This article also revealed the particular roles of MDSCs involved in the regulation networks of postoperative recurrence and metastasis, immunosuppression and inflammation.

Physical- and Chemical-Dually ROS-Responsive Nano-in-Gel Platforms with Sequential Release of OX40 Agonist and PD-1 Inhibitor for Augmented Combination Immunotherapy

Combination immunotherapy synergizing the PD-1 blockade with OX40 agonism has become a research hotspot, due to its enormous potential to overcome the restricted clinical objective response suffered by monotherapy. Questions of timing and sequence have been important aspects of immunotherapies when considering immunologic mechanisms; however, most of the time the straightforward additive approach was taken. Herein, our work is the first to investigate an alternative timing of aOX40 and aPD-1 treatment in melanoma-bearing mice, and it demonstrates that sequential administration (aOX40 first, then aPD-1 following) provided superior antitumor benefits than concurrent treatment. Based on that, to further avoid the limits suffered by solution forms, we adopted pharmaceutical technologies to construct an in situ-formed physical- and chemical-dually ROS-responsive nano-in-gel platform to implement sequential and prolonged release of aPD-1 and aOX40. Equipped with these advantages, the as-prepared (aPD-1NCs&aOX40)@Gels elicited augmented combination immunity and achieved great eradication of both primary and distant melanoma tumors in vivo.

Roles and Applications of Red Blood Cell-Derived Extracellular Vesicles in Health and Diseases

Red blood cell-derived extracellular vesicles (RBCEVs) are vesicles naturally produced by red blood cells and play multiple roles such as acting as cell-to-cell communication messengers in both normal physiological and diseased states. RBCEVs are highly promising delivery vehicles for therapeutic agents such as biomolecules and nucleic acids as they are easy to source, safe, and versatile. RBCEVs autonomously target the liver and pass the blood-brain barrier into the brain, which is highly valuable for the treatment of liver and brain diseases. RBCEVs can be modified by various functional units, including various functional molecules and nanoparticles, to improve their active targeting capabilities for tumors or other sites. Moreover, the RBCEV level is significantly shifted in many diseased states; hence, they can also serve as important biomarkers for disease diagnoses. It is clear that RBCEVs have considerable potential in multiple medical applications. In this review, we briefly introduce the biological roles of RBCEVs, presented interesting advances in RBCEV applications, and discuss several challenges that need to be addressed for their clinical translation.

S1PR2/RhoA/ROCK1 pathway promotes inflammatory bowel disease by inducing intestinal vascular endothelial barrier damage and M1 macrophage polarization

Vascular and immune dysfunctions are thought to be related to the pathogenesis of inflammatory bowel disease (IBD), but behind this, the exact mechanism of mucosal vascular endothelial barrier dysfunction and macrophage phenotypic transition is not fully understood. Here, we explored the mechanistic role of sphingosine 1-phosphate receptor 2 (S1PR2) and its downstream G protein RhoA/Rho kinase 1 (ROCK1) signaling pathway in the intestinal endothelial barrier damage and M1 macrophage polarization in IBD. We found that the expression of S1PR2 in intestinal mucosal vascular endothelial cells and macrophages of IBD patients and DSS-induced colitis mice as well as vascular endothelial cells and macrophages treated with LPS in vitro was significantly increased. Knocking down or pharmacologically inhibiting S1PR2 significantly downregulated the expression of RhoA and ROCK1 in vascular endothelial cells and macrophages. Furthermore, inhibition of S1PR2 and ROCK1 reversed the impaired vascular barrier function and M1 macrophage polarization in vivo and in vitro, while reducing ER stress in vascular endothelial cells and glycolysis in macrophages. In addition, inhibition of ER stress or glycolysis reversed LPS-induced impairment of vascular endothelial cell barrier function and M1 macrophage polarization. Collectively, our results indicate that the S1PR2/RhoA/ROCK1 signaling pathway may participate in the pathogenesis of IBD by regulating vascular endothelial barrier function and M1 macrophage polarization.