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Hubbell, J. A.

Publications and source records attributed to Hubbell, J. A..

15 recordsLinked to original sources

Nanotherapy-mediated biased antigen-presenting cell reprogramming supports T cell anergy to prevent type 1 diabetes

Engineering immune tolerance using endogenously expressed autoantigens could enable early intervention in autoimmune disease. Present therapies suppress T cells to slow disease progression. Here, we develop rapamycin-loaded poly(ethylene glycol)-b-poly(propylene sulfide) polymersomes (rPS) to modulate antigen-presenting cells (APCs) during disease-associated antigen presentation. The rPS morphology enables lymphatic drainage following subcutaneous administration to access APCs in draining lymph nodes. Treatment reduced APC costimulatory marker coexpression and shifted CD4+ T cells toward an FR4hi CD73hi anergic phenotype. In a type 1 diabetes (T1D) nonobese diabetic (NOD) mouse model, rPS significantly delayed disease onset relative to the standard of care and selectively prevented hyperglycemia. Mediation via APCs, rPS avoids adverse effects including transient lymphopenia. These findings demonstrate how biomaterial-directed drug delivery can reshape APC--T cell interactions, supporting an antigen-agnostic strategy for delaying autoimmune diabetes without systemic lymphocyte depletion.

bioengineering↗

Serum albumin-fused interleukin-10 prevents neuroinflammation by promoting immunoregulation in the secondary lymphoid organs and limiting immune cell infiltration in the spinal cord

Interleukin-10 (IL-10) is a potent immunoregulatory cytokine that suppresses pro-inflammatory cytokine production, reduces antigen presentation by myeloid cells, promotes M2 macrophage polarization, and inhibits T cell activation. Despite these well-established immunoregulatory functions, efforts to harness recombinant IL-10 therapeutically have been limited by its short plasma half-life and poor retention in the secondary lymphoid organs (SLOs), key sites of autoreactive T cell priming in autoimmune disease. Previously, we engineered a fusion of serum albumin and IL-10 (SA-IL-10) with extended half-life and enhanced exposure in the SLOs following intravenous administration. Here, we integrate human transcriptomic analyses and a murine model of neuroinflammation, experimental autoimmune encephalomyelitis (EAE), to investigate how sustained IL-10 exposure in the SLOs modulates immune responses under inflammatory conditions. Human single-cell RNA sequencing analyses revealed reduced IL-10 expression alongside increased IL-10 receptor expression across multiple immune cell populations in treatment-naive patients with multiple sclerosis (MS), motivating the investigation of IL-10-based immunomodulatory strategies. Prophylactic SA-IL-10 administration prevented the development and progression of EAE with superior efficacy to wild type IL-10 and comparable protection to fingolimod, an FDA-approved MS therapy. Immunophenotyping of the SLOs revealed that SA-IL-10 suppressed pathogenic, antigen-specific ROR{gamma}t+ Foxp3- TH17 T cells, CD86+ M1-like macrophages, CD86+ dendritic cells, and pro-inflammatory cytokine production, while expanding immunoregulatory CD206+ M2-like macrophages and increasing the frequency of multiple checkpoint markers (CTLA-4, PD-1, TIGIT, ICOS) on GATA3+ Foxp3- TH2 cells. Despite the absence of direct central nervous system targeting, SA-IL-10 treatment also reduced the infiltration of macrophages, dendritic cells, and CD4+ T cells into the spinal cord. Repeated SA-IL-10 administration was well tolerated, as treated EAE mice gained significantly more body weight over the course of treatment compared to PBS- and WT IL-10-treated controls, and exhibited plasma biochemistry parameters comparable to control animals at study endpoint. Together, these findings demonstrate that increasing IL-10 exposure in the SLOs suppresses neuroinflammation by promoting immunoregulation.

immunology↗

Membrane localisation and checkpoint blockade enhance xenoantigen delivery to redirect pre-existing immunity against tumours

Cancer immunotherapies often rely on the recognition of tumour antigens, which strongly limits their efficacy upon heterogeneous antigen expression or downregulation. A strategy to overcome this limitation is to redirect pre-existing antiviral immunity against tumours through the delivery of xenoantigens. While many studies have addressed this by repurposing licensed vaccines, we here investigated the underlying mechanisms of immune redirection via the delivery of non-adjuvanted xenoantigen proteins, thereby avoiding confounding adjuvant- or pathogen-specific effects. Using B16F10 melanoma cells engineered to express the model antigen OVA, we found that tumour rejection in pre-immunised mice depends on the subcellular localisation of the xenoantigen, with membrane-bound antigens eliciting stronger rejection than dose-matched soluble cytoplasmic antigens. Enhanced rejection of membrane-bound OVA expressing tumours was associated with stronger CD4+ T cell responses. In addition, pre-immunisation also increased recruitment of inflammatory monocytes and macrophages at the tumour site. To translate this concept therapeutically, we developed a membrane-targeting OVA fusion protein which, upon intratumoural delivery, redirected pre-existing immunity and made tumours responsive to anti-PD-1 therapy. Importantly, these findings were further validated using the clinically relevant varicella zoster virus (VZV) glycoprotein E (gE) antigen and the licensed varicella vaccine Varivax. Our approach provides a mechanistic and translational perspective for treating poorly immunogenic tumours, leveraging widespread pathogen-specific immune memory in combination with anti-PD1 therapy in cancer patients.

cancer biology↗

Composite biomaterials of polyelectrolyte complex micelle nanoparticles in hyaluronic acid gels enable local, targeted miR-92a inhibition and enhanced angiogenesis in diabetic wound repair

Diabetic wounds are characterized by various cellular deficiencies, particularly insufficient angiogenesis. MicroRNA 92a (miR-92a) is a known factor in diabetic wounds that perpetuates non-healing wound phenotypes by inhibiting angiogenesis. Therefore, its local inhibition at wound sites has therapeutic potential. To achieve this, we combine a nanoparticle formulation of polyelectrolyte complex micelles (PCMs) delivering miR-92a inhibitors with a hyaluronic acid (HA) gel formulation suitable for topical application to wound sites. The nanoparticles, formed by polyelectrolyte complexation of poly(ethylene glycol)-block-poly(L-lysine) with RNA cargo, are functionalized with targeting peptides against vascular cell adhesion molecule 1 (VCAM-1) to improve affinity for inflamed endothelial cells. We demonstrate effective PCM encapsulation and controlled release from gel formulations in vitro and in vivo. These PCMs are taken up in vivo by endothelial cells and exert functional transcriptional effects on miR-92a and its downstream targets. Furthermore, our composite PCM-gel formulation significantly accelerates wound closure in diabetic mouse models and improves angiogenesis, consistent with the known role of miR-92a inhibition in vascular regeneration. This work demonstrates a highly translatable formulation for improved wound healing, and lays the framework for modular nanoparticle-gel systems that can achieve local, cell-targeted RNA delivery. HighlightsPolyelectrolyte complex micelles (PCMs) can be combined with hyaluronic acid gels. VCAM-1 targeted PCMs released from gels are taken up by endothelial cells. PCM-gels deliver miR-92a inhibitors to modulate downstream gene expression in vivo. PCM-gels accelerate wound healing and enhance angiogenesis in diabetic mice.

bioengineering↗

Zwitterionic hydrogel designs for conducting polymers enable bioelectronics with suppressed foreign body response

For long-term, continuous operation of implantable biosensors and electrophysiological devices, the foreign body response (FBR) is a major obstacle that needs to be overcome. As the FBR progresses, any implanted device will become damaged and isolated from its physiological environment, due to encapsulation by fibrotic tissue and inflammatory immune cells. To achieve more compatible and low-impedance biointerfaces, conducting polymers, such as PEDOT:PSS, have been extensively explored as ideal materials. However, FBR on such conducting polymers remains an unmet challenge. We report a zwitteronic-hydrogel-based double-network design for PEDOT:PSS that can significantly suppress the FBR by 64%, in addition to improving conductivity by more than one order of magnitude. Surprisingly, the FBR level of this design is even lower than that of the parent zwitteronic hydrogel by 53%. Our further immunological investigations at the histological, cellular, and transcriptomic levels give deeper insights into the unique effects that come from the chemical heterogeneity. Furthermore, chronic electrocardiographic recording in mice demonstrate the benefit of this material design to long-term, implanted electrophysiology, which provides indications for the future development of immunocompatible electronic polymers.

bioengineering↗

An extracellular matrix coating similar to articular cartilage inhibits the differentiation of myofibroblasts and limits the development of implant-induced fibrosis

Fibrosis is involved in 45% of deaths in the United States, with no treatment options to reverse progression of the disease. Implantable devices (such as joint replacements, chips, stents, artificial organs, biosensors, catheters, heart valves, scaffolds for tissue engineering, etc.) can trigger a foreign body response, in which fibrotic tissue covers the implant and impedes its function. Myofibroblast are a key cellular component of scar tissue. To explore the relationship between extracellular matrix-based coatings and fibrosis, we coated tissue-culture surfaces using a library of extracellular matrix (ECM) proteins and then performed an in-vitro screen for myofibroblast differentiation on the coated surfaces as an indicator of fibrotic potential. The protein and proteoglycan components of cartilage (collagen II, biglycan, decorin, and chondroitin sulfate) were individually anti-fibrotic. Further, mixtures of collagen II, biglycan, decorin, and chondroitin sulfate inhibited myofibroblast differentiation to a greater degree than collagen II, biglycan, decorin, or chondroitin sulfate as individual coatings. Next, we performed an in-vivo model of a foreign-body response. Implanting an uncoated implant subcutaneously into mice resulted in a thicker layer of fibrotic scar tissue than implants coated with a cartilage-like ECM mixture. Our results indicate that the ECM microenvironment is key to the initiation, progression, and maintenance of fibrosis.

immunology↗

Engineered Flt3L Drives Tolerogenic State to Attenuate Anti-drug Antibody Responses

Immune reactions to protein drugs present substantial challenges to protein replacement for treating congenital diseases and metabolic deficiencies, due to the lack of endogenous tolerance or the protein drugs partial or total non-human origin. We sought to transiently modify the immune environment when the adaptive response to the drug antigen is mounted to lessen future reactions upon continued therapeutic treatment, without modifying the drug itself. Herein, we characterize a recombinant fusion of the cytokine Flt3L to serum albumin and describe a novel pathway of Flt3L-mediated immune regulation. We highlight reduced activation of dendritic cells (DC) as well as an increased frequency of DCs expressing LAP, a TGF-{beta} precursor. These effects in combination with low doses of the exogenous antigen led to less TH2 differentiation. This enabled a tolerance-biasing induction regimen to significantly decrease anti-drug antibodies upon repeated exposure to a clinically used, immunogenic fungal enzyme, rasburicase. This induction regimen reduced the Tfh compartment and increased Tfh cells expressing Foxp3 and PD-L1, suggesting a regulatory response. Overall, we introduce the use of a Flt3L variant as an induction therapeutic to modulate the innate immune response, thereby attenuating the adaptive reaction to antigenic protein drugs and addressing an unmet clinical need.

bioengineering↗

LDL-Binding IL-10 Reduces Vascular Inflammation in Atherosclerotic Mice

Atherosclerosis is a chronic inflammatory disease associated with the accumulation of low-density lipoprotein (LDL) in arterial walls. Higher levels of the anti-inflammatory cytokine IL-10 in serum are correlated with reduced plaque burden. However, cytokine therapies have not translated well to the clinic, partially due to their rapid clearance and pleiotropic nature. Here, we engineered IL-10 to overcome these challenges by hitchhiking on LDL to atherosclerotic plaques. Specifically, we constructed fusion proteins in which one domain is IL-10 and the other is an antibody fragment (Fab) that binds to protein epitopes of LDL. In murine models of atherosclerosis, we show that systemically administered Fab-IL-10 constructs bind circulating LDL and traffic to atherosclerotic plaques. One such construct, 2D03-IL-10, significantly reduces aortic immune cell infiltration to levels comparable to healthy mice, whereas non-targeted IL-10 has no therapeutic effect. Mechanistically, we demonstrate that 2D03-IL-10 preferentially associates with foamy macrophages and reduces pro-inflammatory activation markers. This platform technology can be applied to a variety of therapeutics and shows promise as a potential targeted anti-inflammatory therapy in atherosclerosis.

bioengineering↗

Seryl-butyrate: a prodrug that enhances butyrate's oral bioavailability and suppresses autoimmune arthritis and experimental autoimmune encephalomyelitis

Butyrate, a metabolite produced by commensal bacteria, has been intensively studied for its immunomodulatory effects on various immune cells, including T regulatory cells, macrophages, and dendritic cells. Butyrates development as a drug has been limited by its poor oral bioavailability due to its rapid metabolism in the gut, its low potency and thus high dosing, and its foul smell and taste. By simply esterifying butyrate to serine (O-butyryl-L-serine, SerBut), a design based on the concept of utilizing amino acid transporters to escape the gut and enhance systemic uptake thus increasing bioavailability, we developed an odorless and tasteless compound for oral administration. In the collagen antibody-induced arthritis (CAIA) and experimental autoimmune encephalomyelitis (EAE) murine models of rheumatoid arthritis and multiple sclerosis, we demonstrated that SerBut significantly ameliorated disease severity, modulated key immune cell populations both systemically and in disease-associated tissues, and reduced inflammatory responses without compromising global immune response to vaccination. Our findings highlight SerBut as a promising next-generation therapeutic agent for autoimmune and inflammatory diseases.

bioengineering↗

Synthetically mannosylated antigens induce antigen-specific humoral tolerance and reduce anti-drug antibody responses to immunogenic biologics

Immunogenic biologics trigger an anti-drug antibody (ADA) response in patients, which reduces efficacy and increases adverse reactions. Our laboratory has previously shown that targeting protein antigen to the liver microenvironment can reduce antigen-specific T cell responses; herein, we present a strategy to increase delivery of otherwise immunogenic biologics to the liver via conjugation to a synthetic mannose polymer (p(Man)). This delivery leads to reduced antigen-specific T follicular helper cell and B cell responses resulting in diminished ADA production, which is maintained throughout subsequent administrations of the native biologic. We found that p(Man)-antigen treatment impairs the ADA response against recombinant uricase, a highly immunogenic biologic, without a dependence on hapten immunodominance or control by Tregs. We identify increased TCR signaling and increased apoptosis and exhaustion in T cells as effects of p(Man)-antigen treatment via transcriptomic analyses. This modular platform may enhance tolerance to biologics, enabling long-term solutions for an ever-increasing healthcare problem.

bioengineering↗

Glycopolymer-conjugated antigens as an inverse vaccine platform prevent anaphylaxis in a pre-clinical model of food allergy

The only FDA-approved oral immunotherapy for a food allergy provides protection against accidental exposure to peanuts. However, this therapy often causes discomfort or side effects and requires long-term commitment. Better preventive and therapeutic solutions are urgently needed. We have developed a tolerance-inducing vaccine technology that utilizes glycosylation-modified antigens to induce antigen-specific non-responsiveness. The glycosylation-modified antigens were administered intravenously (i.v.) or subcutaneously (s.c.) and were found to traffic to the liver or lymph nodes, respectively, leading to preferential internalization by antigen-presenting cells, educating the immune system to respond in an innocuous way. In a mouse model of cows milk allergy, treatment with glycosylation-modified {beta}- lactoglobulin (BLG) was effective in preventing the onset of allergy. In addition, s.c. administration of glycosylation-modified BLG showed superior safety and potential in treating existing allergies in combination with an anti-CD20 co-therapy. This platform may provide an antigen-specific immunomodulatory strategy to prevent and treat food allergies.

bioengineering↗

Microbial metabolite butyrate-prodrug polymeric micelles promote gut health and treat food allergies

The microbiome modulates host immunity and aids in maintenance of tolerance in the gut, where microbial and food-derived antigens are abundant. Modern lifestyle practices, including diet and antibiotic use, have depleted beneficial taxa, specifically butyrate-producing Clostridia. This depletion is associated with the rising incidence of food allergy, inflammatory bowel diseases, and other noncommunicable chronic diseases. Although butyrate is known to play important roles in regulating gut immunity and maintaining epithelial barrier function, its clinical translation is challenging due to its offensive odor and quick absorption in the upper gut. Here, we have developed two polymeric micelle systems, one with a neutral charge (NtL-ButM) and one with a negative charge (Neg-ButM) that release butyrate from their polymeric core in different regions of the gastrointestinal tract when administered intragastrically to mice. We show that these butyrate-containing micelles, used in combination, restore a barrier-protective response in mice treated with either dextran sodium sulfate or antibiotics. Moreover, butyrate micelle treatment protects peanut-allergic dysbiotic mice from an anaphylactic reaction to peanut challenge and rescues their antibiotic-induced dysbiosis by increasing the abundance of Clostridium Cluster XIVa. Butyrate micelle treatment also reduces the severity of colitis in a murine model. By restoring microbial and mucosal homeostasis, these butyrate-prodrug polymeric micelles may function as a new, antigen-agnostic approach for the treatment of allergic and inflammatory disease.

bioengineering↗

Blocking antibodies against integrin-α3, integrin-αM, and integrin-αMβ2 de-differentiate myofibroblasts and reverse lung and kidney fibroses in a mouse model

Fibrosis is involved in 45% of deaths in the United States, and no treatment exists to reverse the progression of the disease. Myofibroblasts are key to the progression and maintenance of fibrosis. We investigated features of cell adhesion necessary for monocytes to differentiate into myofibroblasts, seeking to identify pathways key to myofibroblast differentiation. Blocking antibodies against integrins 3, M, and M{beta}2 de-differentiate myofibroblasts in vitro, lower the pro-fibrotic secretome of myofibroblasts, and reverse lung and kidney fibrosis in vivo. Decorins collagen-binding peptide directs blocking antibodies (against integrins-3, -M, -M{beta}2) to both fibrotic lungs and fibrotic kidneys, reducing the dose of antibody necessary to reverse fibrosis. This targeted immunotherapy blocking key integrins may be an effective therapeutic for the treatment and reversal of fibrosis. SummaryBlocking antibodies against integrins-3, -M, and -M{beta}2 can be targeted to sites of fibrosis, reverse lung and kidney fibroses, and offer the potential to bring immunotherapy to fibrosis

immunology↗

Generation of potent cellular and humoral immunity against SARS-CoV-2 antigens via conjugation to a polymeric glyco-adjuvant

The SARS-CoV-2 virus has caused an unprecedented global crisis, and curtailing its spread requires an effective vaccine which elicits a diverse and robust immune response. We have previously shown that vaccines made of a polymeric glyco-adjuvant conjugated to an antigen were effective in triggering such a response in other disease models and hypothesized that the technology could be adapted to create an effective vaccine against SARS-CoV-2. The core of the vaccine platform is the copolymer p(Man-TLR7), composed of monomers with pendant mannose or a toll-like receptor 7 (TLR7) agonist. Thus, p(Man-TLR7) is designed to target relevant antigen-presenting cells (APCs) via mannose-binding receptors and then activate TLR7 upon endocytosis. The p(Man-TLR7) construct is amenable to conjugation to protein antigens such as the Spike protein of SARS-CoV-2, yielding Spike-p(Man-TLR7). Here, we demonstrate Spike-p(Man-TLR7) vaccination elicits robust antigen-specific cellular and humoral responses in mice. In adult and elderly wild-type mice, vaccination with Spike-p(Man-TLR7) generates high and long-lasting titers of anti-Spike IgGs, with neutralizing titers exceeding levels in convalescent human serum. Interestingly, adsorbing Spike-p(Man-TLR7) to the depot-forming adjuvant alum, amplified the broadly neutralizing humoral responses to levels matching those in mice vaccinated with formulations based off of clinically-approved adjuvants. Additionally, we observed an increase in germinal center B cells, antigen-specific antibody secreting cells, activated T follicular helper cells, and polyfunctional Th1-cytokine producing CD4+ and CD8+ T cells. We conclude that Spike-p(Man-TLR7) is an attractive, next-generation subunit vaccine candidate, capable of inducing durable and robust antibody and T cell responses.

bioengineering↗

Laminin heparin-binding peptides promiscuously bind growth factors and enhance diabetic wound healing

Laminin, as a key component of the basement membrane extracellular matrix (ECM), regulates tissue morphogenesis. We show that multiple laminin isoforms promiscuously bind to growth factors (GFs) with high affinity, through their heparin binding domains (HBDs) located in the a chain LG domains. Interestingly, these domains also bind to syndecan cell-surface receptors, promoting attachment of fibroblasts and endothelial cells. We next explore application of these multifunctional laminin HBDs in skin healing in the type 2 diabetic mouse. We demonstrate that covalent incorporation of laminin HBDs into fibrin matrix enables the slow-release of GFs. Incorporation of the 33043-3067 laminin HBD significantly enhances in vivo wound-healing efficacy of vascular endothelial cell growth factor (VEGF)-A165 and platelet-derived growth factor (PDGF)-BB, under conditions where the GFs alone in fibrin are inefficacious. This laminin HBD peptide may be clinically useful by improving biomaterials as both GF reservoirs and cell scaffolds, leading to effective tissue regeneration.

bioengineering↗