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1.
bioRxiv ; 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38496534

RESUMO

Toll-like receptors (TLRs) recognize pathogen- and damage-associated molecular patterns and, in turn, trigger the release of cytokines and other immunostimulatory molecules. As a result, TLR agonists are increasingly being investigated as vaccine adjuvants, though many of these agonists are small molecules that quickly diffuse away from the vaccination site, limiting their co-localization with antigens and, thus, their effect. Here, the small-molecule TLR7 agonist 1V209 is conjugated to a positively-charged multidomain peptide (MDP) hydrogel, K 2 , which was previously shown to act as an adjuvant promoting humoral immunity. Mixing the 1V209-conjugated K 2 50:50 with the unfunctionalized K 2 produces hydrogels that retain the shear-thinning and self-healing physical properties of the original MDP, while improving the solubility of 1V209 more than 200-fold compared to the unconjugated molecule. When co-delivered with ovalbumin as a model antigen, 1V209-functionalized K 2 produces antigen-specific IgG titers that were statistically similar to alum, the gold standard adjuvant, and a significantly lower ratio of Th2-associated IgG1 to Th1-associated IgG2a than alum, suggesting a more balanced Th1 and Th2 response. Together, these results suggest that K 2 MDP hydrogels functionalized with 1V209 are a promising adjuvant for vaccines against infectious diseases, especially those benefiting from a combined Th1 and Th2 immune response. Table of Contents: Activation of toll-like receptors (TLRs) stimulates a signaling cascade to induce an immune response. A TLR7 agonist was conjugated to an injectable peptide hydrogel, which was then used to deliver a model vaccine antigen. This platform produced antibody titers similar to the gold standard adjuvant alum and demonstrated an improved balance between Th1- and Th2-mediated immunity over alum.

2.
Cardiovasc Res ; 120(6): 630-643, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38230606

RESUMO

AIMS: Human pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) provide a platform to identify and characterize factors that regulate the maturation of CMs. The transition from an immature foetal to an adult CM state entails coordinated regulation of the expression of genes involved in myofibril formation and oxidative phosphorylation (OXPHOS) among others. Lysine demethylase 5 (KDM5) specifically demethylates H3K4me1/2/3 and has emerged as potential regulators of expression of genes involved in cardiac development and mitochondrial function. The purpose of this study is to determine the role of KDM5 in iPSC-CM maturation. METHODS AND RESULTS: KDM5A, B, and C proteins were mainly expressed in the early post-natal stages, and their expressions were progressively downregulated in the post-natal CMs and were absent in adult hearts and CMs. In contrast, KDM5 proteins were persistently expressed in the iPSC-CMs up to 60 days after the induction of myogenic differentiation, consistent with the immaturity of these cells. Inhibition of KDM5 by KDM5-C70 -a pan-KDM5 inhibitor, induced differential expression of 2372 genes, including upregulation of genes involved in fatty acid oxidation (FAO), OXPHOS, and myogenesis in the iPSC-CMs. Likewise, genome-wide profiling of H3K4me3 binding sites by the cleavage under targets and release using nuclease assay showed enriched of the H3K4me3 peaks at the promoter regions of genes encoding FAO, OXPHOS, and sarcomere proteins. Consistent with the chromatin and gene expression data, KDM5 inhibition increased the expression of multiple sarcomere proteins and enhanced myofibrillar organization. Furthermore, inhibition of KDM5 increased H3K4me3 deposits at the promoter region of the ESRRA gene and increased its RNA and protein levels. Knockdown of ESRRA in KDM5-C70-treated iPSC-CM suppressed expression of a subset of the KDM5 targets. In conjunction with changes in gene expression, KDM5 inhibition increased oxygen consumption rate and contractility in iPSC-CMs. CONCLUSION: KDM5 inhibition enhances maturation of iPSC-CMs by epigenetically upregulating the expressions of OXPHOS, FAO, and sarcomere genes and enhancing myofibril organization and mitochondrial function.


Assuntos
Diferenciação Celular , Ácidos Graxos , Células-Tronco Pluripotentes Induzidas , Miócitos Cardíacos , Miofibrilas , Oxirredução , Fosforilação Oxidativa , Miócitos Cardíacos/enzimologia , Miócitos Cardíacos/metabolismo , Humanos , Ácidos Graxos/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/enzimologia , Miofibrilas/metabolismo , Miofibrilas/enzimologia , Células Cultivadas , Histonas/metabolismo , Histonas/genética , Proteína 2 de Ligação ao Retinoblastoma/metabolismo , Proteína 2 de Ligação ao Retinoblastoma/genética , Regulação da Expressão Gênica no Desenvolvimento , Mitocôndrias Cardíacas/enzimologia , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/genética , Regiões Promotoras Genéticas
3.
Physiol Rep ; 12(1): e15902, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38163670

RESUMO

Although zinc deficiency (secondary to malnutrition) has long been considered an important contributor to morbidity and mortality of infectious disease (e.g. diarrhea disorders), epidemiologic data (including randomized controlled trials with supplemental zinc) for such a role in lower respiratory tract infection are somewhat ambiguous. In the current study, we provide the first preclinical evidence demonstrating that although diet-induced acute zinc deficiency (Zn-D: ~50% decrease) did not worsen infection induced by either influenza A (H1N1) or methicillin-resistant staph aureus (MRSA), Zn-D mice were sensitive to the injurious effects of superinfection of H1N1 with MRSA. Although the mechanism underlying the sensitivity of ZnD mice to combined H1N1/MRSA infection is unclear, it was noteworthy that this combination exacerbated lung injury as shown by lung epithelial injury markers (increased BAL protein) and decreased genes related to epithelial integrity in Zn-D mice (surfactant protein C and secretoglobins family 1A member 1). As bacterial pneumonia accounts for 25%-50% of morbidity and mortality from influenza A infection, zinc deficiency may be an important pathology component of respiratory tract infections.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Desnutrição , Staphylococcus aureus Resistente à Meticilina , Pneumonia Bacteriana , Animais , Camundongos , Pneumonia Bacteriana/complicações , Staphylococcus aureus , Zinco
4.
Res Sq ; 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37886600

RESUMO

Poly(glycerol sebacate) (PGS) is a biodegradable, elastomeric polymer that has been explored for applications ranging from tissue engineering to drug delivery and wound repair. Despite its promise, its biomedical utility is limited by its rapid, and largely fixed, degradation rate. Additionally, its preparation requires high temperatures for long periods of time, rendering it incompatible with heat-sensitive molecules, complex device geometries, and high-throughput production. In this study, we synthesized methacrylated PGS (PGS-M), imparting the ability to rapidly photocross-link the polymer. Increasing the degree of methacrylation was found to slow PGS-M degradation; PGS-M (5.5 kDa) disks with 21% methacrylation lost 43% of their mass over 11 weeks in vivo whereas 47% methacrylated disks lost just 14% of their mass over the same period. Increasing the methacrylation also extended the release of encapsulated daunorubicin by up to two orders of magnitude in vitro, releasing drug over months instead of one week. Like PGS, PGS-M exhibited good biocompatibility, eliciting limited inflammation and fibrous encapsulation when implanted subcutaneously. These studies are the first to perform long-term studies demonstrating the ability to tune PGS-M degradation rate, use PGS-M to release drug, demonstrate sustained release of drug from PGS-M, and evaluate PGS-M behavior in vivo. Taken together, these studies show that PGS-M offers several key advantages over PGS for drug delivery and tissue engineering, including rapid curing, facile loading of drugs without exposure to heat, tunable degradation rates, and tunable release kinetics, all while retaining the favorable biocompatibility of PGS.

5.
J Biomed Mater Res A ; 2023 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-37740704

RESUMO

Pharmaceutical drugs, including vaccines, pre- and post-exposure prophylactics, and chronic drug therapies, are crucial tools in the prevention and treatment of infectious diseases. These drugs have the ability to increase survival and improve patient quality of life; however, infectious diseases still accounted for more than 10.2 million deaths in 2019 before the COVID-19 pandemic. High mortality can be, in part, attributed to challenges in the availability of adequate drugs and vaccines, limited accessibility, poor drug bioavailability, the high cost of some treatments, and low patient adherence. A majority of these factors are logistical rather than technical challenges, providing an opportunity for existing drugs and vaccines to be improved through formulation. Injectable controlled-release drug delivery systems are one class of formulations that have the potential to overcome many of these limitations by releasing their contents in a sustained manner to reduce the need for frequent re-administration and improve clinical outcomes. This review provides an overview of injectable controlled drug delivery platforms, including microparticles, nanoparticles, and injectable gels, detailing recent developments using these systems for single-injection vaccination, long-acting prophylaxis, and sustained-release treatments for infectious disease.

6.
ACS Nano ; 17(12): 11290-11308, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37276377

RESUMO

Cancer phototheranostics have the potential for significantly improving the therapeutic effectiveness, as it can accurately diagnose and treat cancer. However, the current phototheranostic platforms leave much to be desired and are often limited by tumor hypoxia. Herein, a Schottky junction nanozyme has been established between a manganese-bridged cobalt-phthalocyanines complex and Ti3C2Tx MXene nanosheets (CoPc-Mn/Ti3C2Tx), which can serve as an integrative type I and II photosensitizer for enhancing cancer therapeutic efficacy via a photoacoustic imaging-guided multimodal chemodynamic/photothermal/photodynamic therapy strategy under near-infrared (808 nm) light irradiation. The Schottky junction not only possessed a narrow-bandgap, enhanced electron-hole separation ability and exhibited a potent redox potential but also enabled improved H2O2 and O2 supplying performances in vitro. Accordingly, the AS1411 aptamer-immobilized CoPc-Mn/Ti3C2Tx nanozyme illustrated high accuracy and excellent anticancer efficiency through a multimodal therapy strategy in in vitro and in vivo experiments. This work presents a valuable method for designing and constructing a multifunctional nanocatalytic medicine platform for synergistic cancer therapy of solid tumors.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Fotoquimioterapia/métodos , Peróxido de Hidrogênio , Titânio/uso terapêutico , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Linhagem Celular Tumoral , Microambiente Tumoral , Nanopartículas/uso terapêutico
7.
Adv Drug Deliv Rev ; 199: 114904, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37263542

RESUMO

The global pharmaceutical market has recently shifted its focus from small molecule drugs to peptide, protein, and nucleic acid drugs, which now comprise a majority of the top-selling pharmaceutical products on the market. Although these biologics often offer improved drug specificity, new mechanisms of action, and/or enhanced efficacy, they also present new challenges, including an increased potential for degradation and a need for frequent administration via more invasive administration routes, which can limit patient access, patient adherence, and ultimately the clinical impact of these drugs. Controlled-release systems have the potential to mitigate these challenges by offering superior control over in vivo drug levels, localizing these drugs to tissues of interest (e.g., tumors), and reducing administration frequency. Unfortunately, adapting controlled-release devices to release biologics has proven difficult due to the poor stability of biologics. In this review, we summarize the current state of controlled-release peptides and proteins, discuss existing techniques used to stabilize these drugs through encapsulation, storage, and in vivo release, and provide perspective on the most promising opportunities for the clinical translation of controlled-release peptides and proteins.


Assuntos
Produtos Biológicos , Sistemas de Liberação de Medicamentos , Humanos , Preparações de Ação Retardada , Proteínas/química , Peptídeos/química
8.
J Vis Exp ; (195)2023 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-37246855

RESUMO

The current guidelines for rabies post-exposure prophylaxis require multiple injections administered over several weeks. This can be disproportionately burdensome to those living in low- and middle-income countries (LMICs), where the majority of deadly exposures to rabies occur. Different drug delivery strategies have been explored to condense vaccine regimens to a single injection by encapsulating antigens into polymeric particles. However, harsh stressors during the encapsulation process can cause denaturation of the encapsulated antigen. This article describes a method for encapsulating the rabies virus (RABV) antigen into polymeric microparticles that exhibit tunable pulsatile release. This method, termed Particles Uniformly Liquified and Sealed to Encapsulate Drugs (PULSED), generates microparticles using soft lithography to create inverse polydimethylsiloxane (PDMS) molds from a multi-photon, 3D-printed master mold. Poly(lactic-co-glycolic acid) (PLGA) films are then compression-molded into the PDMS molds to generate open-faced cylinders that are filled with concentrated RABV using a piezoelectric dispensing robot. These microstructures are then sealed by heating the top of the particles, allowing the material to flow and form a continuous, nonporous polymeric barrier. Post-fabrication, an enzyme-linked immunosorbent assay (ELISA) specific to the detection of intact trimeric rabies virus glycoprotein is used to confirm the high recovery of immunogenic antigen from the microparticles.


Assuntos
Vacina Antirrábica , Vírus da Raiva , Raiva , Humanos , Raiva/prevenção & controle , Polímeros , Ensaio de Imunoadsorção Enzimática , Antígenos Virais
9.
bioRxiv ; 2023 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-37090524

RESUMO

Rationale: Human pluripotent stem cell-derived CMs (iPSC-CMs) are a valuable tool for disease modeling, cell therapy and to reconstruct the CM maturation process and identify, characterize factors that regulate maturation. The transition from immature fetal to adult CM entails coordinated regulation of the mature gene programming, which is characterized by the induction of myofilament and OXPHOS gene expression among others. Recent studies in Drosophila , C. elegans, and C2C12 myoblast cell lines have implicated the histone H3K4me3 demethylase KDM5 and its homologs, as a potential regulator of developmental gene program and mitochondrial function. We speculated that KDM5 may potentiate the maturation of iPSC-CMs by targeting a conserved epigenetic program that encompass mitochondrial OXPHOS and other CM specific maturation genes. Objectives: The purpose of this study is to determine the role of KDM5 in iPSC-CM maturation. Methods and Results: Immunoblot analysis revealed that KDM5A, B, and C expression was progressively downregulated in postnatal cardiomyocytes and absent in adult hearts and CMs. Additionally, KDM5 proteins were found to be persistently expressed in iPSC-CMs up to 60 days after the onset of myogenic differentiation, consistent with the immaturity of these cells. Inhibition of KDM5 by KDM5-C70 -a pan-KDM5 inhibitor-resulted in differential regulation of 2,372 genes including upregulation of Fatty acid oxidation (FAO), OXPHOS, and myogenic gene programs in iPSC-CMs. Likewise, genome-wide profiling of H3K4me3 binding sites by the CUT&RUN assay revealed enriched H3K4me3 peaks at the promoter regions of FAO, OXPHOS, and sarcomere genes. Consistent with the chromatin and gene expression data, KDM5 inhibition led to increased expression of multiple sarcomere proteins, enhanced myofibrillar organization and improved calcium handling. Furthermore, inhibition of KDM5 increased H3K4me3 deposits at the promoter region of the ESRRA gene, which is known to regulate OXPHOS and cardiomyocyte maturation, and resulted in its increased RNA and protein levels. Finally, KDM5 inhibition increased baseline, peak, and spare oxygen consumption rates in iPSC-CMs. Conclusions: KDM5 regulates the maturation of iPSC-CMs by epigenetically regulating the expression of ESRRA, OXPHOS, FAO, and sarcomere genes and enhancing myofibril organization and mitochondrial function.

10.
Adv Mater ; 35(22): e2300228, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36862114

RESUMO

Pulsatile drug delivery systems have the potential to improve patient adherence and therapeutic efficacy by providing a sequence of doses in a single injection. Herein, a novel platform, termed Particles Uniformly Liquified and Sealed to Encapsulate Drugs (PULSED) is developed, which enables the high-throughput fabrication of microparticles exhibiting pulsatile release. In PULSED, biodegradable polymeric microstructures with an open cavity are formed using high-resolution 3D printing and soft lithography, filled with drug, and sealed using a contactless heating step in which the polymer flows over the orifice to form a complete shell around a drug-loaded core. Poly(lactic-co-glycolic acid) particles with this structure can rapidly release encapsulated material after delays of 10 ± 1, 15 ± 1, 17 ± 2, or 36 ± 1 days in vivo, depending on polymer molecular weight and end group. The system is even compatible with biologics, releasing over 90% of bevacizumab in its bioactive form after a two-week delay in vitro. The PULSED system is highly versatile, offering compatibility with crystalline and amorphous polymers, easily injectable particle sizes, and compatibility with several newly developed drug loading methods. Together, these results suggest that PULSED is a promising platform for creating long-acting drug formulations that improve patient outcomes due to its simplicity, low cost, and scalability.


Assuntos
Sistemas de Liberação de Medicamentos , Polímeros , Humanos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Liberação Controlada de Fármacos , Polímeros/química , Composição de Medicamentos/métodos , Tamanho da Partícula
11.
Nat Rev Drug Discov ; 22(5): 387-409, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36973491

RESUMO

Poor medication adherence is a pervasive issue with considerable health and socioeconomic consequences. Although the underlying reasons are generally understood, traditional intervention strategies rooted in patient-centric education and empowerment have proved to be prohibitively complex and/or ineffective. Formulating a pharmaceutical in a drug delivery system (DDS) is a promising alternative that can directly mitigate many common impediments to adherence, including frequent dosing, adverse effects and a delayed onset of action. Existing DDSs have already positively influenced patient acceptability and improved rates of adherence across various disease and intervention types. The next generation of systems have the potential to instate an even more radical paradigm shift by, for example, permitting oral delivery of biomacromolecules, allowing for autonomous dose regulation and enabling several doses to be mimicked with a single administration. Their success, however, is contingent on their ability to address the problems that have made DDSs unsuccessful in the past.


Assuntos
Sistemas de Liberação de Medicamentos , Adesão à Medicação , Humanos
12.
Bioconjug Chem ; 34(1): 193-203, 2023 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-36580277

RESUMO

Recently, there has been increased interest in using mannan as an immunomodulatory bioconjugate. Despite notable immunological and functional differences between the reduced (R-Man) and oxidized (O-Man) forms of mannan, little is known about the impact of mannan oxidation state on its in vivo persistence or its potential controlled release from biomaterials that may improve immunotherapeutic or prophylactic efficacy. Here, we investigate the impact of oxidation state on the in vitro and in vivo release of mannan from a biocompatible and immunostimulatory multidomain peptide hydrogel, K2(SL)6K2 (abbreviated as K2), that has been previously used for the controlled release of protein and small molecule payloads. We observed that O-Man released more slowly from K2 hydrogels in vitro than R-Man. In vivo, the clearance of O-Man from K2 hydrogels was slower than O-Man alone. We attributed the slower release rate to the formation of dynamic imine bonds between reactive aldehyde groups on O-Man and the lysine residues on K2. This imine interaction was also observed to improve K2 + O-Man hydrogel strength and shear recovery without significantly influencing secondary structure or peptide nanofiber formation. There were no observed differences in the in vivo release rates of O-Man loaded in K2, R-Man loaded in K2, and R-Man alone. These data suggest that, after subcutaneous injection, R-Man naturally persists longer in vivo than O-Man and minimally interacts with the peptide hydrogel. These results highlight a potentially critical, but previously unreported, difference in the in vivo behavior of O-Man and R-Man and demonstrate that K2 can be used to normalize the release of O-Man to that of R-Man. Further, since K2 itself is an adjuvant, a combination of O-Man and K2 could be used to enhance the immunostimulatory effects of O-Man for applications such as infectious disease vaccines and cancer immunotherapy.


Assuntos
Nanofibras , Humanos , Nanofibras/química , Mananas , Preparações de Ação Retardada , Hidrogéis/química , Peptídeos/química
13.
Proc Natl Acad Sci U S A ; 119(51): e2211534119, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36508653

RESUMO

Food fortification is an effective strategy to address vitamin A (VitA) deficiency, which is the leading cause of childhood blindness and drastically increases mortality from severe infections. However, VitA food fortification remains challenging due to significant degradation during storage and cooking. We utilized an FDA-approved, thermostable, and pH-responsive basic methacrylate copolymer (BMC) to encapsulate and stabilize VitA in microparticles (MPs). Encapsulation of VitA in VitA-BMC MPs greatly improved stability during simulated cooking conditions and long-term storage. VitA absorption was nine times greater from cooked MPs than from cooked free VitA in rats. In a randomized controlled cross-over study in healthy premenopausal women, VitA was readily released from MPs after consumption and had a similar absorption profile to free VitA. This VitA encapsulation technology will enable global food fortification strategies toward eliminating VitA deficiency.


Assuntos
Deficiência de Vitamina A , Vitamina A , Feminino , Ratos , Animais , Alimentos Fortificados , Estudos Cross-Over , Culinária , Micronutrientes
14.
Sci Transl Med ; 14(671): eabo3445, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36383683

RESUMO

Not all patients with cancer and severe neutropenia develop fever, and the fecal microbiome may play a role. In a single-center study of patients undergoing hematopoietic cell transplant (n = 119), the fecal microbiome was characterized at onset of severe neutropenia. A total of 63 patients (53%) developed a subsequent fever, and their fecal microbiome displayed increased relative abundances of Akkermansia muciniphila, a species of mucin-degrading bacteria (P = 0.006, corrected for multiple comparisons). Two therapies that induce neutropenia, irradiation and melphalan, similarly expanded A. muciniphila and additionally thinned the colonic mucus layer in mice. Caloric restriction of unirradiated mice also expanded A. muciniphila and thinned the colonic mucus layer. Antibiotic treatment to eradicate A. muciniphila before caloric restriction preserved colonic mucus, whereas A. muciniphila reintroduction restored mucus thinning. Caloric restriction of unirradiated mice raised colonic luminal pH and reduced acetate, propionate, and butyrate. Culturing A. muciniphila in vitro with propionate reduced utilization of mucin as well as of fucose. Treating irradiated mice with an antibiotic targeting A. muciniphila or propionate preserved the mucus layer, suppressed translocation of flagellin, reduced inflammatory cytokines in the colon, and improved thermoregulation. These results suggest that diet, metabolites, and colonic mucus link the microbiome to neutropenic fever and may guide future microbiome-based preventive strategies.


Assuntos
Microbioma Gastrointestinal , Transplante de Células-Tronco Hematopoéticas , Neoplasias , Neutropenia , Camundongos , Animais , Propionatos , Verrucomicrobia , Muco/metabolismo , Mucinas/metabolismo , Dieta , Neutropenia/metabolismo , Neoplasias/metabolismo
15.
Sci Transl Med ; 14(666): eabm1732, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-36223447

RESUMO

Diagnostics and drug delivery technologies engineered for low-resource settings aim to meet their technical design specifications using strategies that are compatible with limited equipment, infrastructure, and operator training. Despite many preclinical successes, very few of these devices have been translated to the clinic. Here, we identify factors that contribute to the clinical success of diagnostics and drug delivery systems for low-resource settings, including the need to engage key stakeholders at an early stage, and provide recommendations for the clinical translation of future medical technologies.


Assuntos
Sistemas de Liberação de Medicamentos
16.
Biomater Sci ; 10(21): 6217-6229, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36102692

RESUMO

Adjuvants play a critical role in enhancing vaccine efficacy; however, there is a need to develop new immunomodulatory compounds to address emerging pathogens and to expand the use of immunotherapies. Multidomain peptides (MDPs) are materials composed of canonical amino acids that form injectable supramolecular hydrogels under physiological salt and pH conditions. MDP hydrogels are rapidly infiltrated by immune cells in vivo and have previously been shown to influence cytokine production. Therefore, we hypothesized that these immunostimulatory characteristics would allow MDPs to function as vaccine adjuvants. Herein, we demonstrate that loading antigen into MDP hydrogels does not interfere with their rheological properties and that positively charged MDPs can act as antigen depots, as demonstrated by their ability to release ovalbumin (OVA) over a period of 7-9 days in vivo. Mice vaccinated with MDP-adjuvanted antigen generated significantly higher IgG titers than mice treated with the unadjuvanted control, suggesting that these hydrogels potentiate humoral immunity. Interestingly, MDP hydrogels did not elicit a robust cellular immune response, as indicated by the lower production of IgG2c and smaller populations of tetramer-positive CD8+ T splenocytes compared to mice vaccinated alum-adjuvanted OVA. Together, the data suggest that MDP hydrogel adjuvants strongly bias the immune response towards humoral immunity while evoking a very limited cellular immune response. As a result, MDPs may have the potential to serve as adjuvants for applications that benefit exclusively from humoral immunity.


Assuntos
Hidrogéis , Imunidade Humoral , Camundongos , Animais , Ovalbumina , Adjuvantes Imunológicos/química , Antígenos , Peptídeos , Adjuvantes Farmacêuticos , Imunoglobulina G , Aminoácidos , Citocinas
17.
World J Gastroenterol ; 28(34): 5058-5075, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36160646

RESUMO

BACKGROUND: A gap remains in documenting the impact of anti-tumor necrosis factor therapy on disease burden in ulcerative colitis (UC) patients treated in a real-world setting. The use of patient-reported outcomes (PROs) has been discussed as a primary endpoint in the context of the FDA PRO Guidance, for labelling purposes. Specifically, the efficacy and safety of adalimumab have been demonstrated in pivotal trials; however, data are needed to understand how clinical results translate into improvements in key aspects of the daily lives of UC patients, such as symptoms, health-related quality of life (HRQoL), and disability. AIM: To assess real-world effectiveness of adalimumab on PRO measures in patients with moderate-to-severe UC. METHODS: UCanADA was a single arm, prospective, 1-year multicenter Canadian post-marketing observational study in which multiple PRO questionnaires were completed-with psychologic distress/depression symptoms as the primary endpoint-by patients with moderate-to-severe UC. Assessments were performed during patients' routine care visit schedule, which was at the initiation of adalimumab (baseline), after induction (approximately 8 wk), and 52 wk after baseline. Additional optional assessments between weeks 8 and 52 were collected at least once but no more than two times during this period. Serious safety events and per-protocol adverse events were collected. RESULTS: From 23 Canadian centres, 100 patients were enrolled and 48 completed the study. Measured with the Patient Health Questionnaire-9 items at week 52, 61.5% (40/65) [95% confidence interval (CI): 49.7%-73.4%] of the patients improved in psychologic distress/depression symptoms, which was slightly higher in completers [65.9% (29/44); 95%CI: 51.9%-79.9%)]. At week 52, clinical response and clinical remission were achieved respectively by 65.7% (44/73) and 47.8% (32/73) of the patients. The odds of improving depressive symptoms for those achieving a clinical remission at week 52 was 7.94 higher compared with those not achieving a clinical remission (CI: 1.42, 44.41; P = 0.018). Significant changes from baseline to weeks 8 and 52 were observed in disability, HRQoL, and fatigue. Meaningful improvement was reported in work impairment. CONCLUSION: At week 52, over 60% of the UCanADA patients had depressive symptoms significantly reduced, as well as HRQoL, fatigue symptoms, and work impairment improved. No new safety signals were detected.


Assuntos
Colite Ulcerativa , Adalimumab/efeitos adversos , Canadá , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/patologia , Efeitos Psicossociais da Doença , Fadiga , Humanos , Estudos Prospectivos , Qualidade de Vida , Indução de Remissão , Resultado do Tratamento
18.
J Can Assoc Gastroenterol ; 5(4): 169-176, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35919766

RESUMO

Crohn's disease (CD) is associated with reduced quality of life, increased absenteeism and high direct medical costs resulting from frequent hospitalizations and surgeries. Tumor necrosis factor-alpha inhibitors (TNFi's) have transformed the therapeutic landscape and enabled a shift from a symptom control to a treat-to-target strategy. The Effect of Tight Control Management on Crohn's Disease (CALM) trial demonstrated tight control (TC), with TNFi dose changes informed by biochemical markers of inflammation, achieved higher mucosal healing rates compared with conventional management (CM) based on symptoms. A Markov model compared TC and CM strategies from the perspective of the Canadian public payer using patient-observation data from the CALM trial. A regression model estimated weekly CD Activity Index-based transition matrices over a 5-year horizon and included covariates to improve extrapolation of outcomes beyond the 48-week trial assessment period. Costs of CD-related hospitalizations, biomarker tests and adalimumab injections were sourced from public data. Other direct medical costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICERs) were calculated. Absenteeism was monetized and included in a sensitivity analysis. Over the 5-year time horizon, TC reduced hospitalization costs by 64% compared with CM. Other direct medical costs were reduced by 22%; adalimumab costs increased by 38%, generating an ICER of $35,168 per QALY gained. Absenteeism costs were reduced by 54%, and, when that was included in the model, TC became dominant compared with CM. Management of CD with TC is cost-effective compared with CM in Canada and is dominant if indirect costs associated with absenteeism are included. Trial registration number: NCT01235689.

19.
ACS Nano ; 16(5): 8076-8094, 2022 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-35442624

RESUMO

Improving the effectiveness of cancer therapy will require tools that enable more specific cancer targeting and improved tumor visualization. Theranostics have the potential for improving cancer care because of their ability to serve as both diagnostics and therapeutics; however, their diagnostic potential is often limited by tissue-associated light absorption and scattering. Herein, we develop CuInSe2@ZnS:Mn quantum dots (QDs) with intrinsic multifunctionality that both enable the accurate localization of small metastases and act as potent tumor ablation agents. By leveraging the growth kinetics of a ZnS shell on a biocompatible CuInSe2 core, Mn doping, and folic acid functionalization, we produce biocompatible QDs with high near-infrared (NIR)-II fluorescence efficiency up to 31.2%, high contrast on magnetic resonance imaging (MRI), and preferential distribution in 4T1 breast cancer tumors. MRI-enabled contrast of these nanoprobes is sufficient to timely identify small metastases in the lungs, which is critically important for preventing cancer spreading and recurrence. Further, exciting tumor-resident QDs with NIR light produces both fluorescence for tumor visualization through radiative recombination pathways as well as heat and radicals through nonradiative recombination pathways that kill cancer cells and initiate an anticancer immune response, which eliminates tumor and prevents tumor regrowth in 80% of mice.


Assuntos
Neoplasias , Pontos Quânticos , Camundongos , Animais , Compostos de Zinco , Neoplasias/patologia , Imageamento por Ressonância Magnética/métodos
20.
Bioengineering (Basel) ; 8(11)2021 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-34821721

RESUMO

Future infectious disease outbreaks are inevitable; therefore, it is critical that we maximize our readiness for these events by preparing effective public health policies and healthcare innovations. Although we do not know the nature of future pathogens, antigen-agnostic platforms have the potential to be broadly useful in the rapid response to an emerging infection-particularly in the case of vaccines. During the current COVID-19 pandemic, recent advances in mRNA engineering have proven paramount in the rapid design and production of effective vaccines. Comparatively, however, the development of new adjuvants capable of enhancing vaccine efficacy has been lagging. Despite massive improvements in our understanding of immunology, fewer than ten adjuvants have been approved for human use in the century since the discovery of the first adjuvant. Modern adjuvants can improve vaccines against future pathogens by reducing cost, improving antigen immunogenicity, and increasing antigen stability. In this perspective, we survey the current state of adjuvant use, highlight potentially impactful preclinical adjuvants, and propose new measures to accelerate adjuvant safety testing and technology sharing to enable the use of "off-the-shelf" adjuvant platforms for rapid vaccine testing and deployment in the face of future pandemics.

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