Organ-on-a-chip systems are miniaturized microfluidic 3D human tissue and organ models designed to recapitulate the important biological and physiological parameters of their in vivo counterparts. ...They have recently emerged as a viable platform for personalized medicine and drug screening. These in vitro models, featuring biomimetic compositions, architectures, and functions, are expected to replace the conventional planar, static cell cultures and bridge the gap between the currently used preclinical animal models and the human body. Multiple organoid models may be further connected together through the microfluidics in a similar manner in which they are arranged in vivo, providing the capability to analyze multiorgan interactions. Although a wide variety of human organ-on-a-chip models have been created, there are limited efforts on the integration of multisensor systems. However, in situ continual measuring is critical in precise assessment of the microenvironment parameters and the dynamic responses of the organs to pharmaceutical compounds over extended periods of time. In addition, automated and noninvasive capability is strongly desired for long-term monitoring. Here, we report a fully integrated modular physical, biochemical, and optical sensing platform through a fluidics-routing breadboard, which operates organ-on-a-chip units in a continual, dynamic, and automated manner. We believe that this platform technology has paved a potential avenue to promote the performance of current organ-on-a-chip models in drug screening by integrating a multitude of real-time sensors to achieve automated in situ monitoring of biophysical and biochemical parameters.
Microvascular muscle transfer is the gold standard for reanimation following chronic facial nerve paralysis, however, despite the regenerative capacity of peripheral motor axons, poor reinnervation ...often results in sub-optimal function. We hypothesized that injection of alginate hydrogels releasing growth factors directly into donor tissue would promote reinnervation, muscle regeneration, and function. A murine model of sciatic nerve ligation and neurorrhaphy was first used to assess the ability of gel delivery of vascular endothelial growth factor (VEGF) and insulin-like growth factor-1 (IGF-1) to promote functional reinnervation. VEGF + IGF-1 gel delivery to aged mice resulted in prolonged ability to control toe movement, increased toe spreading, and improved static sciatic index score, indicative of improved sciatic nerve and neuromuscular junction function. Further, a 26% increase in muscle fiber area, and 2.8 and 3.0-fold increases in muscle contraction force and velocity, respectively, were found compared to blank alginate in the murine model. This strategy was subsequently tested in a rabbit model of craniofacial gracilis muscle transplantation. Electromyography demonstrated a 71% increase in compound muscle action potential 9 weeks after transplantation following treatment with VEGF + IGF-1 alginate, compared to blank alginate in the rabbit model. Improving functional innervation in transplanted muscle via a hydrogel source of growth factors may enhance the therapeutic outcomes of facial palsy treatments and, more broadly, muscle transplantations.
Although disease in a majority of rheumatoid arthritis (RA) patients is often initially limited to one or a few joints, currently approved medications including anti-tumor necrosis factor-α antibody ...(α-TNF) are injected systemically. Given that α-TNF systemic injection typically does not cure RA and involves risk of treatment-related adverse events, one possible approach to enhance therapeutic efficacy and reduce α-TNF systemic exposure is to retain the antibodies in arthritic joints after local administration. The aim of this study was to evaluate the approach of conferring extracellular matrix (ECM) binding affinity to α-TNF antibodies in a RA model.
α-TNF was chemically conjugated with a promiscuous ECM-binding peptide derived from placenta growth factor 2 (PlGF-2
). The binding activity of PlGF-2
-conjugated α-TNF (PlGF-2
-α-TNF) against ECM proteins was assessed by ELISA and by immunostaining on human cartilage specimens. The effect of conjugation on antibody function was assessed as a neutralizing activity against osteoclast differentiation. Retention at the injection site and therapeutic efficacy of PlGF-2
-α-TNF were tested in a collagen antibody-induced arthritis (CAIA) model in the mouse.
PlGF-2
peptide conjugation conferred α-TNF with affinity to ECM proteins without impairment of antigen recognition. PlGF-2
-α-TNF locally injected at a paw in the CAIA model was retained for at least 96 h at the injection site, whereas unmodified α-TNF was dispersed rapidly after injection. Local treatment with unmodified α-TNF did not suppress the arthritis score relative to isotype controls. By contrast, local administration of PlGF-2
-α-TNF suppressed arthritis development almost completely in the treated paw even at a 1000× lower dose.
These data demonstrate that retention of α-TNF in arthritic joints can suppress arthritis development and enhance therapeutic efficacy. This simple bioengineering approach of ECM-binding peptide conjugation offers a powerful and clinically translational approach to treat RA.
Objective
Rheumatoid arthritis (RA) is a major autoimmune disease that causes synovitis and joint damage. Although clinical trials have been performed using interleukin‐10 (IL‐10), an ...antiinflammatory cytokine, as a potential treatment of RA, the therapeutic effects of IL‐10 have been limited, potentially due to insufficient residence in lymphoid organs, where antigen recognition primarily occurs. This study was undertaken to engineer an IL‐10–serum albumin (SA) fusion protein and evaluate its effects in 2 murine models of RA.
Methods
SA‐fused IL‐10 (SA–IL‐10) was recombinantly expressed. Mice with collagen antibody–induced arthritis (n = 4–7 per group) or collagen‐induced arthritis (n = 9–15 per group) were injected intravenously with wild‐type IL‐10 or SA–IL‐10, and the retention of SA–IL‐10 in the lymph nodes (LNs), immune cell composition in the paws, and therapeutic effect of SA–IL‐10 on mice with arthritis were assessed.
Results
SA fusion to IL‐10 led to enhanced accumulation in the mouse LNs compared with unmodified IL‐10. Intravenous SA–IL‐10 treatment restored immune cell composition in the paws to a normal status, elevated the frequency of suppressive alternatively activated macrophages, reduced IL‐17A levels in the paw‐draining LN, and protected joint morphology. Intravenous SA–IL‐10 treatment showed similar efficacy as treatment with an anti–tumor necrosis factor antibody. SA–IL‐10 was equally effective when administered intravenously, locally, or subcutaneously, which is a benefit for clinical translation of this molecule.
Conclusion
SA fusion to IL‐10 is a simple but effective engineering strategy for RA therapy and has potential for clinical translation.
Interleukin-4 (IL-4) suppresses the development of multiple sclerosis in a murine model of experimental autoimmune encephalomyelitis (EAE). Here, we show that, in mice with EAE, the accumulation and ...persistence in the lymph nodes and spleen of a systemically administered serum albumin (SA)-IL-4 fusion protein leads to higher efficacy in preventing disease development than the administration of wild-type IL-4 or of the clinically approved drug fingolimod. We also show that the SA-IL-4 fusion protein prevents immune-cell infiltration in the spinal cord, decreases integrin expression in antigen-specific CD4
T cells, increases the number of granulocyte-like myeloid-derived suppressor cells (and their expression of programmed-death-ligand-1) in spinal cord-draining lymph nodes and decreases the number of T helper 17 cells, a pathogenic cell population in EAE. In mice with chronic EAE, SA-IL-4 inhibits immune-cell infiltration into the spinal cord and completely abrogates immune responses to myelin antigen in the spleen. The SA-IL-4 fusion protein may be prophylactically and therapeutically advantageous in the treatment of multiple sclerosis.
The COVID-19 pandemic underscores the need for rapid, safe, and effective vaccines. In contrast to some traditional vaccines, nanoparticle-based subunit vaccines are particularly efficient in ...trafficking antigens to lymph nodes, where they induce potent immune cell activation. Here, we developed a strategy to decorate the surface of oxidation-sensitive polymersomes with multiple copies of the SARS-CoV-2 spike protein receptor-binding domain (RBD) to mimic the physical form of a virus particle. We evaluated the vaccination efficacy of these surface-decorated polymersomes (RBDsurf) in mice compared to RBD-encapsulated polymersomes (RBDencap) and unformulated RBD (RBDfree), using monophosphoryl-lipid-A-encapsulated polymersomes (MPLA PS) as an adjuvant. While all three groups produced high titers of RBD-specific IgG, only RBDsurf elicited a neutralizing antibody response to SARS-CoV-2 comparable to that of human convalescent plasma. Moreover, RBDsurf was the only group to significantly increase the proportion of RBD-specific germinal center B cells in the vaccination-site draining lymph nodes. Both RBDsurf and RBDencap drove similarly robust CD4+ and CD8+ T cell responses that produced multiple Th1-type cytokines. We conclude that a multivalent surface display of spike RBD on polymersomes promotes a potent neutralizing antibody response to SARS-CoV-2, while both antigen formulations promote robust T cell immunity.
Ischemic diseases, such as peripheral artery disease, affect millions of people worldwide. While CD4+ T-cells regulate angiogenesis and myogenesis, it is not understood how the phenotype of these ...adaptive immune cells regulate these regenerative processes. The secreted factors from different types of CD4+ T-cells (Th1, Th2, Th17, and Treg) were utilized in a series of in vitro assays and delivered from an injectable alginate biomaterial into a murine model of ischemia to study their effects on vascular and skeletal muscle regeneration. Conditioned medium from Th2 and Th17 T-cells enhanced angiogenesis in vitro and in vivo, in part by directly stimulating endothelial sprouting. Th1 conditioned medium induced vascular regression in vitro and provided no benefit to angiogenesis in vivo. Th1, Th2, and Th17 conditioned medium, to varying extents, enhanced muscle precursor cell proliferation and inhibited their differentiation in vitro, and prolonged early stages of muscle regeneration in vivo. Treg conditioned medium had a moderate or no effect on these processes in vitro and no discernible effect in vivo. These findings suggest that Th2 and Th17 T-cells may enhance angiogenesis and myogenesis in ischemic injuries, which may be useful in the design of immunomodulatory biomaterials to treat these diseases.
Short chain fatty acid (SCFAs), such as butyrate, have shown promising therapeutic potential due to their immunomodulatory effects, particularly in maintaining immune homeostasis. However, the ...clinical application of SCFAs is limited by the need for frequent and high oral dosages. Rheumatoid arthritis (RA) is characterized by aberrant activation of peripheral T cells and myeloid cells. In this study, we aimed to deliver butyrate directly to the lymphatics using a polymeric micelle-based butyrate prodrug to induce long-lasting immunomodulatory effects. Notably, negatively charged micelles (Neg-ButM) demonstrated superior efficacy in targeting the lymphatics following subcutaneous (s.c.) administration and were retained in the draining lymph nodes, spleen, and liver for over one month. In the collagen antibody-induced arthritis (CAIA) mouse model of RA, only two s.c. injections of Neg-ButM successfully prevented disease onset and promoted tolerogenic phenotypes in T cells and myeloid cells, both locally and systemically. These results underscore the potential of this strategy in managing inflammatory autoimmune diseases by directly modulating immune responses via lymphatic delivery.
Display omitted
PDF
