Chagas disease, caused by the protozoan Trypanosoma cruzi, is an infectious illness that progresses through acute, indeterminate, and chronic phases. The acute phase often presents mild symptoms, followed by an asymptomatic indeterminate phase. In some cases, the disease advances to chronic Chagas cardiomyopathy, driven by sustained inflammation. Current treatments, benznidazole and nifurtimox, have limited efficacy in this stage and are associated with significant toxicity, highlighting the need for better therapies. PEG-b-PPS loaded with BTAc, exhibited favorable physicochemical properties, including high stability and an average size of 120 nm, suitable for efficient uptake by phagocytic cells such as macrophages. BTAc-loaded polymersomes showed enhanced efficacy against intracellular amastigotes of three T. cruzi strains (CL Brener, Brazil and Y) with IC50 values of 6.17, 24.01, and 30.68 μg/mL, respectively. The formulation simultaneously reduced proinflammatory cytokines to basal levels, suggesting an immunomodulatory potential. Importantly, Förster Resonance Energy Transfer analysis confirmed that BTAc-loaded polymersomes remain intact upon cellular uptake, escape the endosomal compartment, and release their payload directly into the cytosol, which is the intracellular niche where amastigotes persist during chronic infection. These findings underscore the potential of this nanocarrier system as an innovative approach that combines targeted antitrypanosomal therapy with enhanced immunomodulation, offering a promising strategy for the treatment of chronic Chagas disease.

Introduction and Objective: Teplizumab (anti-CD3 antibody) is the first FDA-approved therapy to delay the onset of type 1 diabetes (T1D) and prolong insulin independence. This treatment paves the path for early-intervention strategies to build long-standing, antigen-specific immune tolerance and further prevent T1D. We have previously demonstrated that rapamycin-loaded polymersome nanoparticles (rPS) induce antigen-specific tolerance towards transplanted fully-MHC mismatched islets via a costimulation blockade in mice1. To assess if this strategy can protect native islets and tolerize autoantigens, rPS was benchmarked against anti-CD3 antibody in a spontaneous T1D mouse model. Methods: Rapamycin was encapsulated within nanocarriers fabricated from poly(ethylene) glycol and polypropylene sulfide block copolymer as previously described1. Randomized female nonobese diabetic (NOD) mice (n=16) were received subcutaneous rPS injections or intravenous anti-CD3 (clone 145-2C11) infusions at 8 weeks of age. Blood glucose and weight were routinely monitored in addition to markers of immune and metabolic function. Survival and statistical comparison between groups (Mantel-Cox and Two-Way ANOVA) was performed in GraphPad Prism 10. Results: rPS (6 doses at 0.5, 1, or 2 mg/kg) protected beta cell function and delayed the onset of T1D by at least 9 weeks relative to the untreated and anti-CD3-treated groups (p = 0.041). Only anti-CD3-treated mice developed lymphopenia (100%) and leukopenia (37.5%) during treatment. Insulin autoantibody (IAA) presence was more associated with T1D incidence for anti-CD3-treated mice, but the same trend was not observed in rPS-treated groups. Conclusion: rPS is a promising early-intervention therapy to delay the onset of T1D. rPS leverages antigen presenting cells to reprogram T cells for antigen-specific islet tolerance and can mitigate adverse events of chronic, nonspecific immunosuppression. 1. Burke JA, et al. Nat Nanotechnol. 2022;17(3):319-330. doi:10.1038/s41565-021-01048-2 N.R. Klug: None. E.A. Scott: Other Relationship; AbbVie Inc. J.A. Burke: Consultant; SNC Therapeutics.

In chronic Chagas disease, the persistence of the protozoan Trypanosoma cruzi (T. cruzi) is associated with an extensive inflammatory response that impacts cardiac function. The standard treatment, oral benznidazole, effectively targets the parasitic burden but does not address the chronic inflammation nor prevent the progression of severe cardiomyopathies. This presents an inherent immunotherapeutic challenge, as implementing an anti-inflammatory approach can have the unwanted effect of inhibiting beneficial parasite-specific immunity. Here, we investigated a combination therapy approach using benznidazole and immunomodulatory rapamycin-loaded poly(ethylene glycol)-b-poly(propylene sulfide) polymersome nanocarriers in a chronic Chagas disease murine model with cardiac abnormalities. The combined treatment demonstrated effective management of both inflammation and parasitic burden at systemic and local levels. No systemic reactivation of T. cruzi infection was observed, along with cardioprotective immunomodulatory effects through the modulation of cytokines, management of parasitic burden, and improved cardiac function based on electrocardiography assessment. The combination treatment enhanced a protective cytokine response in the heart, characterized by increased anti-inflammatory IL-10 levels, achieving greater effects than standard benznidazole treatment, and normalized TNF-α levels. Localized immunomodulatory effects, along with parasitic burden control, extended to other solid tissues relevant to parasite pathology and reservoirs. These findings highlight the therapeutic potential of modulating the immune response in chronic Chagas disease with rapamycin polymersomes and emphasize the importance of precise treatment timing in the strategy's efficacy.

While nanomedicine holds great promise for kidney disease, targeted delivery remains a major challenge. Most nanocarriers rely on passive accumulation or epithelial-specific ligands, limiting their utility in complex, inflamed renal environments. In acute kidney injury (AKI), inflammation and vascular dysfunction play central roles, yet targeting strategies beyond the tubule remain underexplored. Here, dual-ligand micelles are developed to enhance nanocarrier localization to the inflamed kidney by simultaneously engaging both organ- and injury-specific cues. Poly(ethylene glycol)-block-poly(propylene sulfide) (PEG-b-PPS) micelles were engineered to display two peptide ligands: CLPVASC, which preferentially distributes to the kidney, and CYNTTTHRC, which binds selectively to inflamed endothelium. These targeting motifs were incorporated via lipid-anchored peptide amphiphiles, enabling modular surface functionalization without disrupting micelle morphology, size, or charge. In vitro, dual-targeted micelles demonstrated enhanced uptake by human endothelial cells exposed to hypoxia-reoxygenation. In vivo, following unilateral renal ischemia-reperfusion injury (IRI) in mice, targeted micelles achieved selective accumulation in the injured kidney, outperforming both non-targeted controls and contralateral kidneys. Off-target distribution to liver, lung, and spleen was markedly reduced, confirming the spatial precision of the dual-ligand approach. This strategy offers a scalable, modular, and biologically informed platform for precision delivery in AKI and related inflammatory conditions.

While monoclonal antibodies have significantly improved cancer treatment, their accumulation in off-target tissues not only limits efficacy, but also induces toxicity. A major contributor to this problem is the mononuclear phagocyte system (MPS). This collection of innate immune cells is a critical regulator of immune homeostasis that effectively scavenges nanoparticles and biologics, preventing their therapeutic effects within solid tumors. Here, pinocytosis inhibitory nanoparticles are demonstrated to safely and temporarily disable the MPS via enhanced delivery of the small molecule actin inhibitor latrunculin A (LatA). This "indirect targeting" strategy is applied to improve anti-programmed death receptor 1 (aPD-1) antibody administration in mice bearing melanoma and colon carcinoma, decreasing aPD-1 interaction with the MPS, avoiding liver toxicity, increasing engagement with target cells, and modulating the immune microenvironment of solid tumors. The resulting change in biodistribution significantly improved safety, anticancer efficacy, and overall survival. Our methodology may be employed to enhance a wide range of monoclonal antibody therapies.

Nanocarriers hold transformative potential for treating anterior segment eye diseases, yet corneal epithelium impermeability necessitates intraocular injection. Given the discomfort and infection risk, an injectable hydrogel-based depot offers a promising strategy for sustained nanocarrier delivery in intraocular therapy. However, because the aqueous humor is a large, fluid-filled environment, achieving spatially confined gelation remains a key challenge as injected materials rapidly diffuse. Herein, we present a composite hydrogel (C-gel) that enables localized in situ gelation and sustained nanocarrier release within the anterior chamber. This is achieved using poly(ethylene glycol)-b-poly(propylene sulfide) (PEG-b-PPS) filomicelles (FMs), whose filamentous structure confines crosslinking reactions spatially, promoting efficient gel formation. As a result, 90% of the injected polymer is retained within the crosslinked hydrogel matrix. Embedded FMs then undergo oxidation-induced cylinder-to-sphere transitions, facilitating gradual release of micellar nanocarriers. The rheological properties, gelation timing, and microstructure of the C-gel are adjustable, allowing precise control of nanocarrier release dynamics. In vivo evaluation in mice confirmed excellent biocompatibility without inducing intraocular pressure elevation, ocular toxicity, or immune cell infiltration. Sustained release of nanocarriers was observed for over a month under conditions mimicking that of the anterior chamber of the eye, underscoring the potential of C-gels for long-term drug delivery in anterior segment eye diseases therapy.

Type 1 diabetes (T1D) is characterized by the autoimmune destruction of insulin-producing β cells within pancreatic islets, the specialized endocrine cell clusters of the pancreas. Islet transplantation has emerged as a β cell replacement therapy, involving the infusion of cadaveric islets into a patient's liver through the portal vein. This procedure offers individuals with T1D the potential to restore glucose control, reducing or even eliminating the need for exogenous insulin therapy. However, it does not address the underlying autoimmune condition responsible for T1D. The need for systemic immunosuppression remains the primary barrier to making islet transplantation a more widespread therapy for patients with T1D. Here, we review recent progress in addressing the key limitations of islet transplantation as a viable treatment for T1D. Concerns over systemic immunosuppression arise from its potential to cause severe side effects, including opportunistic infections, malignancies, and toxicity to transplanted islets. Recognizing the risks, the Edmonton protocol (2000) marked a shift away from glucocorticoids to prevent β cell damage specifically. This transition led to the development of combination immunosuppressive therapies and the emergence of less toxic immunosuppressive and anti-inflammatory drugs. More recent advances in islet transplantation derive from islet encapsulation devices, biomaterial platforms releasing immunomodulatory compounds or surface-modified with immune regulating ligands, islet engineering and co-transplantation with accessory cells. While most of the highlighted studies in this review remain at the preclinical stage using mouse and non-human primate models, they hold significant potential for clinical translation if a transdisciplinary research approach is prioritized.

Type 1 diabetes (T1D) onset is characterized by an autoimmune attack on b islet cells within the pancreas, preventing the insulin secretion required to maintain glucose homeostasis. Targeted modulation of key immunoregulatory cell populations is a promising strategy to restore tolerance to b cells. This strategy can be used to prevent T1D onset or reverse T1D with transplanted islets. To this end, drug delivery systems can be employed to transport immunomodulatory cargo to specific cell populations that inhibit autoreactive T cell -mediated destruction of the b cell mass. The rational engineering of biomaterials into nanoscale and microscale drug carriers can facilitate targeted interactions with immune cells. The physicochemical properties of the biomaterial, the delivered immunomodulatory agent, and the target cell populations are critical variables in the design of these delivery systems. In this review, we discuss recent biomaterialsbased drug delivery approaches to induce islet tolerance and the need to consider both immune and metabolic markers of disease progression.

Solid organ transplantation mobilizes myeloid cells, including monocytes and macrophages, which are central protagonists of allograft rejection. However, myeloid cells can also be functionally reprogrammed by perioperative costimulatory blockade to promote a state of transplantation tolerance. Transplantation tolerance holds promise to reduce complications from chronic immunosuppression and promote long-term survival in transplant recipients. We sought to identify different mediators of transplantation tolerance by performing single-cell RNA sequencing of acute rejecting or tolerized cardiac allografts. This led to the unbiased identification of the transcription factor, hypoxia inducible factor (HIF)-2α, in a subset of tolerogenic monocytes. Using flow cytometric analyses and mice with conditional loss or gain of function, we uncovered that myeloid cell expression of HIF-2α was required for costimulatory blockade–induced transplantation tolerance. While HIF-2α was dispensable for mobilization of tolerogenic monocytes, which were sourced in part from the spleen, it promoted the expression of colony stimulating factor 1 receptor (CSF1R). CSF1R mediates monocyte differentiation into tolerogenic macrophages and was found to be a direct transcriptional target of HIF-2α in splenic monocytes. Administration of the HIF stabilizer, roxadustat, within micelles to target myeloid cells, increased HIF-2α in splenic monocytes, which was associated with increased CSF1R expression and enhanced cardiac allograft survival. These data support further exploration of HIF-2α activation in myeloid cells as a therapeutic strategy for transplantation tolerance.

The clinical translation of many biomolecular therapeutics has been hindered by undesirable pharmacokinetic (PK) properties, inadequate membrane permeability, poor endosomal escape and cytosolic delivery, and/or susceptibility to degradation. Overcoming these challenges merits the development of nanoscale drug carriers (nanocarriers) to improve the delivery of therapeutic cargo. Herein, we implement a flash nanoprecipitation (FNP) approach to produce nanocarriers of diverse vesicular morphologies by using various molecular weight PEG-bl-DEAEMA-co-BMA (PEG-DB) polymers. We demonstrated that FNP can produce uniform (PDI < 0.1) particles after 5 impingements, and that by varying the copolymer hydrophilic mass fraction, FNP enables access to a diverse variety of nanoarchitectures including micelles, unilamellar vesicles (polymersomes), and multi-compartment vesicles (MCVs). We synthesized a library of 2 kDa PEG block copolymers, with DEAEMA-co-BMA second block molecular weights of 3, 6, 12, 15, 20, and 30 kDa. All formulations were both pH responsive, endosomolytic, and capable of loading and cytosolically delivering small negatively charged molecules - albeit to different degrees. Using a B16.F10 melanoma model, we showcased the therapeutic potential of a lead FNP formulated PEG-DB nanocarrier, encapsulating the cyclic dinucleotide (CDN) cGAMP to activate the stimulator of interferon genes (STING) pathway in a therapeutically relevant context. Collectively, these data demonstrate that an FNP process can be used to formulate pH-responsive nanocarriers of diverse morphologies using a PEG-DB polymer system. As FNP is an industrially scalable process, these data address the critical translational challenge of producing PEG-DB nanoparticles at scale. Furthermore, the diverse morphologies produced may specialize in the delivery of distinct biomolecular cargos for other therapeutic applications, implicating the therapeutic potential of this platform in an array of disease applications.

Purpose of review The pathophysiological understanding of kidney-related disorders has profoundly increased; however, tissue-specific and cell-specific treatments in this field remain scarce. Advances in nanomedicine enable alteration of pharmacokinetics and targeted treatments improving efficiency and reducing toxicity. This review addresses recent developments of nanocarriers used for various purposes in the broad field of kidney disease, which may pave a path to new therapeutic and diagnostic solutions employing nanomedicine. Recent findings Controlled delivery of antiproliferative medications enables improved treatment of polycystic kidney disease and fibrosis. Directed anti-inflammatory treatment mitigated glomerulonephritis and tubulointerstitial nephritis. Multiple injury pathways in AKI have been targeted, with therapeutic solutions for oxidative stress, mitochondrial dysfunction, local inflammation and improving self-repair mechanisms. In addition to such treatment development, noninvasive early detection methods (minutes after ischemic insult) have been demonstrated as well. Sustained release of therapies that reduce ischemia–reperfusion injury as well as new aspects for immunosuppression bring hope to improving kidney transplant outcomes. The latest breakthroughs in gene therapy are made achievable by engineering the targeted delivery of nucleic acids for new treatments of kidney disease. Summary Recent advances in nanotechnology and pathophysiological understanding of kidney diseases show potential for translatable therapeutic and diagnostic interventions in multiple etiologies of kidney disease.

INTRODUCTION:Current and developing mast cell therapeutics are reliant on small molecule drugs and biologics, but few are truly selective for mast cells. Most have cellular and disease-specific limitations that require innovation to overcome longstanding challenges to selectively targeting and modulating mast cell behavior. This review is designed to serve as a frame of reference for new approaches that utilize nanotechnology or combine different drugs to increase mast cell selectivity and therapeutic efficacy.AREAS COVERED:Mast cell diseases include allergy and related conditions as well as malignancies. Here, we discuss the targets of existing and developing therapies used to treat these disease pathologies, classifying them into cell surface, intracellular, and extracellular categories. For each target discussed, we discuss drugs that are either the current standard of care, under development, or have indications for potential use. Finally, we discuss how novel technologies and tools can be used to take existing therapeutics to a new level of selectivity and potency against mast cells.EXPERT OPINION:There are many broadly and very few selectively targeted therapeutics for mast cells in allergy and malignant disease. Combining existing targeting strategies with technology like nanoparticles will provide novel platforms to treat mast cell disease more selectively.

Mycobacterium tuberculosis (Mtb) infection elicits both protein and lipid antigen-specific T cell responses. However, the incorporation of lipid antigens into subunit vaccine strategies and formulations has been underexplored, and the characteristics of vaccine-induced Mtb lipid-specific memory T cells have remained elusive. Mycolic acid (MA), a major lipid component of the Mtb cell wall, is presented by human CD1b molecules to unconventional T cell subsets. These MA-specific CD1b-restricted T cells have been detected in the blood and disease sites of Mtb-infected individuals, suggesting that MA is a promising lipid antigen for incorporation into multicomponent subunit vaccines. In this study, we utilized the enhanced stability of bicontinuous nanospheres (BCN) to efficiently encapsulate MA for in vivo delivery to MA-specific T cells, both alone and in combination with an immunodominant Mtb protein antigen (Ag85B). Pulmonary administration of MA-loaded BCN (MA-BCN) elicited MA-specific T cell responses in humanized CD1 transgenic mice. Simultaneous delivery of MA and Ag85B within BCN activated both MA- and Ag85B-specific T cells. Notably, pulmonary vaccination with MA-Ag85B-BCN resulted in the persistence of MA, but not Ag85B, within alveolar macrophages in the lung. Vaccination of MA-BCN through intravenous or subcutaneous route, or with attenuated Mtb likewise reproduced MA persistence. Moreover, MA-specific T cells in MA-BCN-vaccinated mice differentiated into a T follicular helper-like phenotype. Overall, the BCN platform allows for the dual encapsulation and in vivo activation of lipid and protein antigen-specific T cells and leads to persistent lipid depots that could offer long-lasting immune responses.

Abstract Ligand targeted therapy (LTT) is a precision medicine strategy that can selectively target diseased cells while minimizing off‐target effects on healthy cells. Integrin‐targeted LTT has been developed recently for angiogenesis‐related diseases. However, the clinical success is based on the optimal design of the nanoparticles for inducing receptor clustering within the cell membrane. The current study focused on determining the surface density of Ser‐Asp‐Val containing anti‐integrin heptapeptide on poly (ethylene glycol)‐b‐poly(propylene sulfide) micelles (MC) required for anti‐angiogenic effects on HUVECs. Varying peptide density on PEG‐b‐PPS/Pep‐PA MCs (Pep‐PA‐Peptide‐palmitoleic acid) was used in comparison to a random peptide (SGV) and cRGD (cyclic‐Arginine‐Glycine‐Aspartic acid) construct at 5%‐density on MCs. Immunocytochemistry using CD51/CD31 antibody was performed to study the integrin blocking by MCs. In addition, the expression of VWF and PECAM‐1, cell migration and tube formation was evaluated in the presence of PEG‐b‐PPS/Pep‐PA MCs. The results show PEG‐b‐PPS/SDV‐PA MCs with 5%‐peptide density to achieve significantly higher αvβ3 blocking compared to random peptide as well as cRGD. In addition, αvβ3 blocking via MCs further reduced the expression of vWF and PECAM‐1 angiogenesis protein expression in HUVECs. Although a significant level of integrin blocking was observed for 1%‐peptide density on MCs, the cell migration and tube formation were not significantly affected. In conclusion, the results of this study demonstrate that the peptide surface density on PEG‐b‐PPS/Pep‐PA MCs has a significant impact in integrin blocking as well as inhibiting angiogenesis during LTT. The outcomes of this study provides insight into the design of ligand targeted nanocarriers for various disease conditions.

Contact between nanomaterials and biomolecules such as serum proteins leads to “soft” or “hard” corona formation via dynamic or irreversible adsorption, respectively. While soft coronas of antibodies can temporarily retain the ability for immunological recognition, preserving protein function within hard coronas has remained an elusive goal due to the unfolding of protein at the nano-bio interface. Here, we show that poly(propylene sulfone) nanoparticles efficiently and stably adsorb proteins, unexpectedly forming bioactive hard coronas using a facile methodology. This process is permitted by site-specific hydrophobic-hydrophobic interactions between nanoparticle surfaces and proteins, allowing stable simultaneous pre-adsorption of multiple proteins such as enzymes and antibodies. For therapeutic validation, a nanotherapy for enhanced antibody-based targeting of mast cells and inhibition of anaphylaxis was demonstrated in a humanized mouse model. Protein immobilization on the poly(propylene sulfone) surface therefore provides a simple and rapid platform for the design, fabrication, and optimization of bioactive and targeted nanomedicines.

Tuberculosis remains a serious global epidemic and with the rise of multi-drug resistant strains, an efficacious vaccine solution is imperative. Vaccines currently being developed for Mtb utilize protein antigens, which target MHC-restricted conventional T cells, overlooking the potential of Mycobacterium tuberculosis (Mtb) lipid antigens such as mycolic acid (MA), a key lipid found in Mtb cell wall. Mycobacterial lipids are presented by group 1 CD1 molecules (CD1a, b, c) to cognate T cells. Group 1 CD1-restricted T cells can be identified in patients with TB and have been shown to provide protection in Mtb infection. Using biocontinuous nanospheres (BCNs), a type of self-assembled nanostructure able to load both hydrophobic and hydrophilic molecules, we have created a vaccine containing MA. We found that MA BCN is able to effectively activate CD1b-restricted MA-specific T cells in vitro and in vivo. Interestingly, we discovered that MA persists within lung alveolar macrophages for at least 6 weeks after intratracheal vaccination with MA BCN. Antigen archiving was in part due to the encapsulation of MA within BCN. Nanoparticle vaccinations carrying lipid antigens may thus lead to persistent depots of antigen that could offer long-lasting immune response and protection. Supported by grants from NIH (5R01AI145345-03, 1F30AI157314-01, 5T32GM008152-35)

Nanotechnology is revolutionizing many sectors of science, from food preservation to healthcare to energy applications. Since 1995, when the first nanomedicines started being commercialized, drug developers have relied on nanotechnology to improve the pharmacokinetic properties of bioactive molecules. The development of advanced nanomaterials has greatly enhanced drug discovery through improved pharmacotherapeutic effects and reduction of toxicity and side effects. Therefore, highly toxic treatments such as cancer chemotherapy, have benefited from nanotechnology. Considering the toxicity of the few therapeutic options to treat neglected tropical diseases, such as leishmaniasis and Chagas disease, nanotechnology has also been explored as a potential innovation to treat these diseases. However, despite the significant research progress over the years, the benefits of nanotechnology for both diseases are still limited to preliminary animal studies, raising the question about the clinical utility of nanomedicines in this field. From this perspective, this review aims to discuss recent nanotechnological developments, the advantages of nanoformulations over current leishmanicidal and trypanocidal drugs, limitations of nano-based drugs, and research gaps that still must be filled to make these novel drug delivery systems a reality for leishmaniasis and Chagas disease treatment.

Plasmid DNA (pDNA) transfection is advantageous for gene therapies requiring larger genetic elements, including "all-in-one" CRISPR/Cas9 plasmids, but is limited by toxicity as well as poor intracellular release and transfection efficiency in immune cell populations. Here, we developed a synthetic non-viral gene delivery platform composed of poly(ethylene glycol)-b-poly(propylene sulfide) copolymers linked to a cationic dendritic peptide (DP) via a reduceable bond, PEG-b-PPS-ss-DP (PPDP). A library of self-assembling PPDP polymers was synthesized and screened to identify optimal constructs capable of transfecting macrophages with small (pCMV-DsRed, 4.6 kb) and large (pL-CRISPR.EFS.tRFP, 11.7 kb) plasmids. The optimized PPDP construct transfected macrophages, fibroblasts, dendritic cells, and T cells more efficiently and with less toxicity than a commercial Lipo2K reagent, regardless of pDNA size and under standard culture conditions in the presence of serum. The PPDP technology described herein is a stimuli-responsive polymeric nanovector that can be leveraged to meet diverse challenges in gene delivery.