Delivery Of Peptides Research Articles

Biodynamer Nano-Complexes and -Emulsions for Peptide and Protein Drug Delivery.

Therapeutic proteins and peptides offer great advantages compared to traditional synthetic molecular drugs. However, stable protein loading and precise control of protein release pose significant challenges due to the extensive range of physicochemical properties inherent to proteins. The development of a comprehensive protein delivery strategy becomes imperative accounting for the diverse nature of therapeutic proteins. Biodynamers are amphiphilic proteoid dynamic polymers consisting of amino acid derivatives connected through pH-responsive dynamic covalent chemistry. Taking advantage of the amphiphilic nature of the biodynamers, PNCs and DEs were possible to be prepared and investigated to compare the delivery efficiency in drug loading, stability, and cell uptake. As a result, the optimized PNCs showed 3-fold encapsulation (<90%) and 5-fold loading capacity (30%) compared to DE-NPs. PNCs enhanced the delivery efficiency into the cells but aggregated easily on the cell membrane due to the limited stability. Although DE-NPs were limited in loading capacity compared to PNCs, they exhibit superior adaptability in stability and capacity for delivering a wider range of proteins compared to PNCs. Our study highlights the potential of formulating both PNCs and DE-NPs using the same biodynamers, providing a comparative view on protein delivery efficacy using formulation methods.

Non-covalent delivery of native proteins and peptides by phenylboronic cell-penetrating poly(disulfide)s

Poly(disulfide)s have been proposed as delivery carriers, yet their design for native protein delivery without covalent conjugation remain elusive and challenging. Here, we present a type of poly(disulfide)s randomly copolymerized from cell-penetrating cyclic five-membered disulfide (CFMD) monomer (M1) and phenylboronic CFMD monomer (M2) by ring-opening polymerization. The resulted poly(disulfide)s can directly complex a broad range of native, unmodified proteins and peptides via multiple non-covalent forces, regardless of their chemical structure, molecular weight and isoelectric point. The complexation between poly(disulfide)s and proteins can be predominantly internalized by cells via strain-promoted, thiol-mediated translocation, bypassing the classical endocytic pathway. The degradation of the poly(disulfide) is induced by rich intracellular glutathione, thereby timely releasing protein or peptide cargoes in their active form and minimize the cytotoxicity of the carrier. Of note, the surface coating of poly(disulfide) complexes by hyaluronic acid enables the systemic delivery of functional proteins, demonstrating their therapeutic potentials in vivo.

In situ formed antibacterial hydrogel with collagenase-responsive activity for prevention of MRSA-induced osteomyelitis

Osteomyelitis caused by methicillin-resistant Staphylococcus aureus (MRSA) is a challenging and life-threatening disease due to its long duration and deep site of occurrence. Herein, we design an in situ formed antibacterial hydrogel with collagenase-respontive activity for the prevention of MRSA-induced osteomyelitis. This hydrogel is constructed by chemical bonding between a 4-arm polyethylene glycol maleimide (4-Arm-PEG-Mal), an N-terminal maleimidated antimicrobial peptide (Mal-AMP) and a collagenase-cleavable peptide with two thiol groups (HS-VPM-SH). Collagenase-induced hydrogel cleavage confers on-demand delivery of the antimicrobial peptide, thereby enhancing the combating activity against MRSA in an infected environment. The designed hydrogel, namely AMP/VPM/PEG hydrogel, can be formed rapidly in situ under physiological conditions due to the rapid bonding between the maleimide and thiol groups. In the in vivo rat osteomyelitis model, the AMP/VPM/PEG hydrogel can be administered by simply injecting the 4-Arm-PEG-Mal and peptide solutions with a 26G needle, which is a minimally invasive method. In vivo evaluation further demonstrates that AMP/VPM/PEG hydrogel can successfully prevent MRSA-induced osteomyelitis. This work provides a minimally invasive approach for intramedullary delivery of antimicrobial peptides on-demand and may provide a viable strategy for the osteomyelitis prevention in clinic.

The design of an RGD in situ sustained delivery system utilizing scallop byssal protein through genetic engineering

Although bioactive peptides enhancing bone healing have demonstrated effectiveness in treating bone defects, in vivo instability poses a challenge to their clinical application. Currently reported peptide delivery systems do not meet the demands of bone tissue repair regarding stability and peptide release efficacy. Herein, the self-assembling recombinant chimeric protein (Sbp5–2RGD) is developed by genetic engineering with cell adhesion peptide RGD as the targeted peptide and a newly discovered scallop byssal-derived protein Sbp5–2 that can assemble into wet stable films as the structural domain. In vitro studies show that the Sbp5–2RGD film exhibits excellent extensibility and biocompatibility. In vitro and in vivo degradation experiments demonstrate that the film remains stable due to the layer-by-layer degradation mode, resulting in sustained delivery of RGD in situ for up to 4 weeks. Consequently, the film can effectively promote osteogenesis, which accelerates bone defect healing and the implants osseointegration. Cell-level studies further show that the film up-regulates the expression of genes and proteins (ALP, OCN, OSX, OPN, RUNX2, VEGF) associated with osteogenesis and angiogenesis. Overall, this novel protein film represents an intelligent platform for peptide immobilization, protection, and release through its self-assembly, dense structure, and degradation mode, providing a therapeutic strategy for bone repair.

Targeted acidosis mediated delivery of antigenic MHC-binding peptides.

Cytotoxic T lymphocytes are the primary effector immune cells responsible for protection against cancer, as they target peptide neoantigens presented through the major histocompatibility complex (MHC) on cancer cells, leading to cell death. Targeting peptide-MHC (pMHC) complex offers a promising strategy for immunotherapy due to their specificity and effectiveness against cancer. In this work, we exploit the acidic tumor micro-environment to selectively deliver antigenic peptides to cancer using pH(low) insertion peptides (pHLIP). We demonstrated the delivery of MHC binding peptides directly to the cytoplasm of melanoma cells resulted in the presentation of antigenic peptides on MHC, and activation of T cells. This work highlights the potential of pHLIP as a vehicle for the targeted delivery of antigenic peptides and its presentation via MHC-bound complexes on cancer cell surface for activation of T cells with implications for enhancing anti-cancer immunotherapy.

Quality by design (QbD) approach-based development of optimized nanocarrier to achieve quality target product profile (QTPP)-targeted lymphatic delivery

Background. Insulin, commonly used for diabetes treatment, needs better ways to improve its effectiveness and safety due to its challenges with poor permeability and stability. Various system has been developed for oral peptide delivery. The non-targeted system can prevent gastric and enzymatic degradation of peptides but cannot increase the bulk transport of peptides across the membrane. However, the non-selectivity is the limitation of the existing system. Numerous carbohydrate-binding receptors overexpressed on intestinal macrophage cells (M-cells) of gut-associated lymphoid tissue. It is the most desirable site for receptor-mediated endocytosis and lymphatic drug delivery of peptides. Objective. The prime objective of the study was to fabricate mannose ligand conjugated nanoparticles (MNPs) employing a quality-by-design approach to address permeability challenges after oral administration. Herein, the study’s secondary objective of this study is to identify the influencing factor for producing quality products. Considering this objective, the Lymphatic uptake of NPs was selected as a quality target product profile (QTPP), and a systematic study was conducted to identify the critical formulation attributes (CFAs) and critical process parameters (CPP) influencing critical quality attributes (CQAs). Mannosylated Chitosan concentrations (MCs) and TPP concentrations were identified as CFAs, and stirring speed was identified as CPP. Methods. MNPs were prepared by the inotropic gelation method and filled into the enteric-coated capsule to protect from acidic environments. The effect of CFAs and CPP on responses like particle size (X) and entrapment (Y) was observed by Box-Behnken design (BBD). ANOVA statistically evaluated the result to confirm a significant level (p < 0.05). The optimal conditions of NPs were obtained by constructing an overlay plot and determining the desirability value. HPLC and zeta-seizer analysis characterized the lyophilized NPs. Cell-line studies were performed to confirm the safety and M-cell targeting of NPs to enhance Insulin oral bioavailability. Results. The morphology of NPs was revealed by SEM. The developed NPs showed a nearly oval shape with the average size, surface potential, and % drug entrapment were 245.52 ± 3.37 nm, 22.12 ± 2.13 mV, and 76.15 ± 1.3%, respectively. MTT assay result exhibited that MNPs safe and Confocal imaging inference that NPs selectively uptake by the M-cell. Conclusion. BBD experimental design enables the effective formulation of optimized NPs. The statistical analysis estimated a clear assessment of the significance of the process and formulation variable. Cell line study confirms that NPs are safe and effectively uptake by the cell.

Developing Plant Exosomes as an Advanced Delivery System for Cosmetic Peptide.

Peptides are a promising skincare ingredient, but due to their inherent instability and the barrier function of the skin's surface, they often have limited skin absorption and penetration, which can significantly hinder their skincare benefits. To address this, a novel technique called NanoGlow has been introduced for encapsulating peptide-based cosmetic raw materials into engineered nanosized plant-derived exosomes (pExo) to achieve the goal of a healthier and more radiant skin state. In this approach, pExo served as carriers for cosmetic peptides across the intact skin barrier, enhancing their biological effectiveness in skin beauty. The NanoGlow strategy combines chemical activation and physical proencapsulation, boasting a high success rate and straightforward and stable operation, making it suitable for large-scale production. Comprehensive analysis using in vitro cellular absorption and skin penetration models has demonstrated that the nanosized pExo carriers significantly improve peptide penetration into the skin compared to free peptides. Furthermore, in vivo tissue slice studies have shown that pExo carriers efficiently deliver acetyl hexapeptide-8 to the skin's dermis, surpassing the performance of free peptides. Cosmetic skincare effect analysis has also indicated that pExo-loaded cosmetic peptides deliver superior results. Therefore, the NanoGlow technique harnesses the natural size and properties of pExo to maximize the bioavailability of cosmetic peptides, holding great promise for developing advanced peptide delivery systems in both the cosmetic and medical drug industries.

Transmucosal Delivery of Peptides and Proteins Through Nanofibers: Current Status and Emerging Developments.

Advancements in recombinant DNA technology have made proteins and peptides available for diagnostic and therapeutic applications, but their effectiveness when taken orally leads to poor patient compliance, requiring clinical administration. Among the alternative routes, transmucosal delivery has the advantage of being noninvasive and bypassing hepato-gastrointestinal clearance. Various mucosal routes-buccal, nasal, pulmonary, rectal, and vaginal-have been explored for delivering these macromolecules. Nanofibers, due to their unique properties like high surface-area-to-volume ratio, mechanical strength, and improved encapsulation efficiency, serve as promising carriers for proteins and peptides. These nanofibers can be tailored for quick dissolution, controlled release, enhanced encapsulation, targeted delivery, and improved bioavailability, offering superior pharmaceutical and pharmacokinetic performance compared to conventional methods. This leads to reduced dosages, fewer side effects, and enhanced patient compliance. Hence, nanofibers hold tremendous potential for protein/peptide delivery, especially through mucosal routes. This review focuses on the therapeutic application of proteins and peptides, challenges faced in their conventional delivery, techniques for fabricating different types of nanofibers and, various nanofiber-based dosage forms, and factors influencing nanofiber generation. Insights pertaining to the precise selection of materials used for fabricating nanofibers and regulatory aspects have been covered. Case studies wherein the use of specific protein/peptide-loaded nanofibers and delivered via oral/vaginal/nasal mucosa for diagnostic/therapeutic use and related preclinical and clinical studies conducted have been included in this review.

Targeted intracellular delivery of BH3 mimetic peptide inhibits BCL-2 activity and prevents breast cancer development

&lt;p class="MsoNormal" style="margin-top: 12pt; text-align: justify;"&gt;&lt;span lang="EN-US" style="font-family: Cambria, serif; font-size: 14pt;"&gt;Breast cancer, as a malignant tumor with easy metastasis and poor prognosis, threatens the health of women around the world. Increasing studies have shown that the Bcl-2 family of apoptosis-related proteins is often expressed abnormally in breast cancer. The Bcl-2 homology 3 (BH3) mimetic peptide can bind and neutralize Bcl-2, preventing its binding to the apoptosis "effector" proteins Bak and Bax, thereby promoting the apoptosis process. However, there is a lack of effective intracellular delivery system for BH3 to exert its biological activity. Therefore, this study utilized an activatable supercharged polypeptide (ASCP) tumor-targeted delivery platform based on pH and protease response to achieve the targeted release of BH3 at the tumor site. Ultimately, intracellular delivery of BH3 was achieved and induced apoptosis of breast tumor cells, preventing the development of breast cancer.&lt;/span&gt;&lt;/p&gt;

Exploring the biogenic peptide’s potential in combating bacterial zoonosis: application and future prospect – a review

Abstract Worldwide, microbial infections have a serious impact because they cause infectious diseases, death, and significant economic losses. Zoonosis is now a major public health issue on a global scale because of the fast expansion of human exploitation of nature and animal husbandry. Notably, in the past 30 years, over 30 novel human infections have been discovered, 75% of which fall under the category of zoonosis. Resistant strains have emerged as a result of improper use of antibiotics and insufficient infection management posing a serious risk to both public health and the global economy. As alternatives, antimicrobial peptides are showing good results. The majority of living things use antibacterial peptides (ABPs) as a key part of their natural defenses against invading infections. These peptides are cationic, amphipathic, and relatively tiny with varied sequences, structures, and lengths. For the delivery of these efficacious biological peptides, nanoparticles are providing opportunities for effective, safe, and viable delivery. An innovative method of treating infectious diseases is demonstrated by nanoparticles and antibacterial peptides. When ABPs are combined with carrier nanoparticles to optimize distribution, their half-life may be increased, allowing for lower dosages and ultimately lower toxicity. For biological applications, ABPs and nanoparticle conjugates have become effective methods, enabling the treatment, prevention of disease, and detection. More than 50 peptide medications have been made available for purchase on the market as of 2018. Around 25 billion USD is spent on peptide medications each year, including ABPs. But still, there is a gap in the distribution of these ABPs as an alternative to synthetic antibiotics. It might be due to the high cost of these goods. Thus, scientists, researchers, and commercializing companies should work together so that these ABPs with a safe delivery system should be available in the market to combat resistant strains of bacteria. In doing so, we draw attention to the significant advancements made in the field as well as the difficulties still encountered in developing imaging species, active therapies, and nano-drug delivery systems that are functionalized with peptides and proteins for clinical use.

Parafilm® M and Strat-M® as skin simulants in in vitro permeation of dissolving microarray patches loaded with proteins

In vitro permeation studies play a crucial role in early formulation optimisation before extensive animal model investigations. Biological membranes are typically used in these studies to mimic human skin conditions accurately. However, when focusing on protein and peptide transdermal delivery, utilising biological membranes can complicate analysis and quantification processes. This study aims to explore Parafilm®M and Strat-M® as alternatives to dermatomed porcine skin for evaluating protein delivery from dissolving microarray patch (MAP) platforms. Initially, various MAPs loaded with different model proteins (ovalbumin, bovine serum albumin and amniotic mesenchymal stem cell metabolite products) were prepared. These dissolving MAPs underwent evaluation for insertion properties and in vitro permeation profiles when combined with different membranes, dermatomed porcine skin, Parafilm®M, and Strat-M®. Insertion profiles indicated that both Parafilm®M and Strat-M® showed comparable insertion depths to dermatomed porcine skin (in range of 360–430 µm), suggesting promise as membrane substitutes for insertion studies. In in vitro permeation studies, synthetic membranes such as Parafilm®M and Strat-M® demonstrated the ability to bypass protein-derived skin interference, providing more reliable results compared to dermatomed neonatal porcine skin. Consequently, these findings present valuable tools for preliminary screening across various MAP formulations, especially in the transdermal delivery of proteins and peptides.

Polymeric Microparticles as an Efficient Carrier for the delivery of Proteins and Peptides

Polymeric Microparticles as an Efficient Carrier for the delivery of Proteins and Peptides

Nutrition and Cardiovascular Disease: The Potential Role of Marine Bioactive Proteins and Peptides in Thrombosis Prevention.

Thrombus and cardiovascular diseases pose a significant health threat, and dietary interventions have shown promising potential in reducing the incidence of these diseases. Marine bioactive proteins and peptides have been extensively studied for their antithrombotic properties. They can inhibit platelet activation and aggregation by binding to key receptors on the platelet surface. Additionally, they can competitively anchor to critical enzyme sites, leading to the inhibition of coagulation factors. Marine microorganisms also offer alternative sources for the development of novel fibrinolytic proteins, which can help dissolve blood clots. The advancements in technologies, such as targeted hydrolysis, specific purification, and encapsulation, have provided a solid foundation for the industrialization of bioactive peptides. These techniques enable precise control over the production and delivery of bioactive peptides, enhancing their efficacy and safety. However, it is important to note that further research and clinical studies are needed to fully understand the mechanisms of action and therapeutic potential of marine bioactive proteins and peptides in mitigating thrombotic events. The challenges and future application perspectives of these bioactive peptides also need to be explored.

Bioactive peptide relieves glucocorticoid-induced osteoporosis by giant macrocyclic encapsulation

Bioactive peptides play a crucial role in the field of regenerative medicine and tissue engineering. However, their application in vivo and clinic is hindered by their poor stability, short half-life, and low retention rate. Herein, we propose a novel strategy for encapsulating bioactive peptides using giant macrocycles. Platelet-derived growth factor (PDGF) bioactive mimicking peptide Nap-FFGVRKKP (P) was selected as the representative of a bioactive peptide. Quaterphen[4]arene (4) exhibited extensive host-guest complexation with P, and the binding constant was (1.16 ± 0.10) × 107 M−1. In vitro cell experiments confirmed that P + 4 could promote the proliferation of BMSCs by 2.27 times. Even with the addition of the inhibitor dexamethasone (Dex), P + 4 was still able to save 76.94% of the cells in the control group. Compared to the Dex group, the bone mass of the mice with osteoporosis in the P + 4 group was significantly increased. The mean trabecular thickness (Tb.Th) increased by 17.03%, and the trabecular bone volume fraction (BV/TV) values increased by 40.55%. This supramolecular bioactive peptide delivery strategy provides a general approach for delivering bioactive peptides and opens up new opportunities for the development of peptide-based drugs.

Abstract 3882: Targeted degradation of undruggable proteins using a novel heterobifunctional proteomimetic platform

Abstract Of the ~20,000 unique proteins in the human genome, only a subset can be modulated via traditional pharmacological approaches. “Undruggable” targets currently include proteins with pivotal roles in cancer pathogenesis. Our work aims to introduce a new paradigm for engaging these clinically relevant proteins using a modular platform we term the HYbrid DegRAding Copolymers (HYDRACs). HYDRACs multiplex targeting warheads with degradation inducers and have long circulation times plus high cell uptake. Preliminary studies on MYC and RAS, targets of immense pharmaceutical interest, highlight the potential of this platform to revolutionize drug design. Methods: HYDRACs containing MYC- or RAS- targeting peptides randomly copolymerized with degrons were synthesized using ROMP. Fluorescent and biotin-tags were incorporated for use in uptake and pull-down assays. Viability following treatment with MYC-HYDRACs was performed in multiple cell lines with both cellular (MYC-independent lines) and polymer composition controls. Target engagement was assessed via immunoprecipitation and circular dichroism with protein degradation monitored by WB. Unbiased whole proteome analysis and RNAseq were done to confirm observed effects were selectively on-target. In vivo efficacy and biodistribution was assessed in tumor-bearing mice. Results: HYDRACs show high levels of cell uptake and antiproliferative effects at sub-micromolar concentrations in a formulation- and target-dependent manner. Cells treated with MYC-HYDRACs displayed reduced MYC protein levels, which were rescued by proteasome or neddylation inhibition. Swapping out the degron for various validated E3 ligase recruiters maintained MYC degradation, highlighting the “plug-and-play” nature of this approach. On-target activity was confirmed via RNAseq. Biophysical analysis showed strong HYDRAC-protein interactions, orthogonally supported by the presence of target protein following pull-down of biotin-terminated HYDRACs. Target protein degradation only occurred following treatment with an intact HYDRAC compound. Mice bearing MYC-CaP tumors showed delayed tumor growth following treatment with MYC-HYDRACs, with compound accumulation in the tumor for up to 72 h following a single injection. Generalizability was demonstrated against RAS, with RAS-HYDRACs capable of degrading KRAS across multiple different alleles, acting as a pan-KRAS degrader. Conclusions: We present a novel platform technology that addresses the challenges inherent to peptide delivery approaches. HYDRACs have the potential to dramatically alter the drug discovery landscape, allowing for the development of cancer-relevant target modulators for which there are no current viable therapies. We envision the HYDRAC platform as a generalizable approach to designing degraders of proteins of interest, greatly expanding the therapeutic armamentarium for TPD. Citation Format: Max Wang, Mihai Truica, Brayley Gattis, Xiaoyu Zhang, Sarki Abdulkadir, Nathan Gianneschi. Targeted degradation of undruggable proteins using a novel heterobifunctional proteomimetic platform [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3882.

Abstract 3193: Utilizing a pH sensitive peptide (pHLIP) for antigen-directed T cell therapy

Abstract Many targeted therapies, such as antibody drug conjugates (ADCs) and chimeric antigen receptor (CAR) T cell therapies, rely on the identification of an optimal antigen as the cell marker for targeting cancer cells. However, there is a paucity of antigen candidates that are sufficiently specific to epithelial cancers. Therefore, technologies that can mark tumor cells for immune recognition could prove beneficial in the treatment of these solid cancers. pH low insertion peptides (pHLIPs) act as a unique delivery platform that can specifically target the acidic microenvironment of tumors, sparing healthy tissue in the process. We developed a pHLIP-peptide conjugate (pHLIP-SIINFEKL) to deliver the SIINFEKL peptide, an immunogenic fragment of ovalbumin, to investigate antigen delivery and recognition to tumors in vivo. When processed intracellularly, SIINFEKL is presented for immune recognition through the major histocompatibility complex (MHC) class I pathway. We observed selective delivery of pHLIP-SIINFEKL both in vitro and in vivo using fluorescently labeled constructs. In vitro, treatment of melanoma tumor cells with pHLIP-SIINFEKL resulted in recognition by SIINFEKL-specific T cells (OT1), leading to T cell activation and effector function. Mechanistically, we show that this recognition by OT1 cells was abrogated by siRNA knockdown of the β2 microglobulin (β2m) component of MHC class I in the target tumor cells, indicating that an intact antigen processing pathway in the cancer cells is necessary to mediate the effect of pHLIP-directed SIINFEKL delivery. In vivo, pHLIP-SIINFEKL treatment of tumor-bearing mice resulted in recruitment of OT1 T cells and suppression of tumor growth in two syngeneic tumor models in immunocompetent mice, with no effect when mutating either the pHLIP or SIINFEKL components of the conjugate. These results suggest that pHLIP-mediated peptide delivery can provide a novel approach to decorate solid tumors with engineered antigens for enhanced immune recognition and anti-tumor efficacy. Citation Format: Annali M. Yurkevicz, Yanfeng Liu, Peter M. Glazer. Utilizing a pH sensitive peptide (pHLIP) for antigen-directed T cell therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3193.

Process Mass Intensity (PMI): A Holistic Analysis of Current Peptide Manufacturing Processes Informs Sustainability in Peptide Synthesis.

Small molecule therapeutics represent the majority of the FDA-approved drugs. Yet, many attractive targets are poorly tractable by small molecules, generating a need for new therapeutic modalities. Due to their biocompatibility profile and structural versatility, peptide-based therapeutics are a possible solution. Additionally, in the past two decades, advances in peptide design, delivery, formulation, and devices have occurred, making therapeutic peptides an attractive modality. However, peptide manufacturing is often limited to solid-phase peptide synthesis (SPPS), liquid phase peptide synthesis (LPPS), and to a lesser extent hybrid SPPS/LPPS, with SPPS emerging as a predominant platform technology for peptide synthesis. SPPS involves the use of excess solvents and reagents which negatively impact the environment, thus highlighting the need for newer technologies to reduce the environmental footprint. Herein, fourteen American Chemical Society Green Chemistry Institute Pharmaceutical Roundtable (ACS GCIPR) member companies with peptide-based therapeutics in their portfolio have compiled Process Mass Intensity (PMI) metrics to help inform the sustainability efforts in peptide synthesis. This includes PMI assessment on 40 synthetic peptide processes at various development stages in pharma, classified according to the development phase. This is the most comprehensive assessment of synthetic peptide environmental metrics to date. The synthetic peptide manufacturing process was divided into stages (synthesis, purification, isolation) to determine their respective PMI. On average, solid-phase peptide synthesis (SPPS) (PMI ≈ 13,000) does not compare favorably with other modalities such as small molecules (PMI median 168-308) and biopharmaceuticals (PMI ≈ 8300). Thus, the high PMI for peptide synthesis warrants more environmentally friendly processes in peptide manufacturing.

Cellular Uptake and Transport Mechanism Investigations of PEGylated Niosomes for Improving the Oral Delivery of Thymopentin.

Although its immunomodulatory properties make thymopentin (TP5) appealing, its rapid metabolism and inactivation in the digestive system pose significant challenges for global scientists. PEGylated niosomal nanocarriers are hypothesized to improve the physicochemical stability of TP5, and to enhance its intestinal permeability for oral administration. TP5-loaded PEGylated niosomes were fabricated using the thin film hydration method. Co-cultured Caco-2 and HT29 cells with different ratios were screened as in vitro intestinal models. The cytotoxicity of TP5 and its formulations were evaluated using an MTT assay. The cellular uptake and transport studies were investigated in the absence or presence of variable inhibitors or enhancers, and their mechanisms were explored. All TP5 solutions and their niosomal formulations were nontoxic to Caco-2 and HT-29 cells. The uptake of TP5-PEG-niosomes by cells relied on active endocytosis, exhibiting dependence on time, energy, and concentration, which has the potential to significantly enhance its cellular uptake compared to TP5 in solution. Nevertheless, cellular transport rates were similar between TP5 in solution and its niosomal groups. The cellular transport of TP5 in solution was carried out mainly through MRP5 endocytosis and a passive pathway and effluxed by MRP5 transporters, while that of TP5-niosomes and TP5-PEG-niosomes was carried out through adsorptive- and clathrin-mediated endocytosis requiring energy. The permeability and transport rate was further enhanced when EDTA and sodium taurocholate were used as the penetration enhancers. This research has illustrated that PEG-niosomes were able to enhance the cellular uptake and maintain the cellular transport of TP5. This study also shows this formulation's potential to serve as an effective carrier for improving the oral delivery of peptides.

Targeting and monitoring ovarian cancer invasion with an RNAi and peptide delivery system

RNA interference (RNAi) therapeutics are an emerging class of medicines that selectively target mRNA transcripts to silence protein production and combat disease. Despite the recent progress, a generalizable approach for monitoring the efficacy of RNAi therapeutics without invasive biopsy remains a challenge. Here, we describe the development of a self-reporting, theranostic nanoparticle that delivers siRNA to silence a protein that drives cancer progression while also monitoring the functional activity of its downstream targets. Our therapeutic target is the transcription factor SMARCE1, which was previously identified as a key driver of invasion in early-stage breast cancer. Using a doxycycline-inducible shRNA knockdown in OVCAR8 ovarian cancer cells both in vitro and in vivo, we demonstrate that SMARCE1 is a master regulator of genes encoding proinvasive proteases in a model of human ovarian cancer. We additionally map the peptide cleavage profiles of SMARCE1-regulated proteases so as to design a readout for downstream enzymatic activity. To demonstrate the therapeutic and diagnostic potential of our approach, we engineered self-assembled layer-by-layer nanoparticles that can encapsulate nucleic acid cargo and be decorated with peptide substrates that release a urinary reporter upon exposure to SMARCE1-related proteases. In an orthotopic ovarian cancer xenograft model, theranostic nanoparticles were able to knockdown SMARCE1 which was in turn reported through a reduction in protease-activated urinary reporters. These LBL nanoparticles both silence gene products by delivering siRNA and noninvasively report on downstream target activity by delivering synthetic biomarkers to sites of disease, enabling dose-finding studies as well as longitudinal assessments of efficacy.

Polymersomes for Therapeutic Protein and Peptide Delivery: Towards Better Loading Properties.

Therapeutics based on proteins and peptides have profoundly transformed the landscape of treatment for diseases, from diabetes mellitus to cancers, yet the short half-life and low bioavailability of therapeutic proteins and peptides hinder their wide applications. To break through this bottleneck, biomolecules-loaded polymersomes with strong adjustability and versatility have attracted more and more attentions recently. Loading proteins or peptides into polymersomes is the first but extremely important step towards developing high-quality formulation products. However, increasing protein and peptide loading content is quite challenging due to the inherent nature of self-assembled vesicle formation mechanism and physiochemical characteristics of biomacromolecules. This review highlights the potential of polymersomes as the next-generation therapeutic proteins and peptides carrier and emphatically introduces novel approaches and recent progress to achieve satisfactory encapsulation capability of polymersomes for proteins and peptides. On the one hand, with the help of intermolecular interactions, such as electrostatic, lipid-protein, and hydrophobic interactions, the drug loading could be significantly improved. On the other hand, loading improvement could be attained through innovation of preparation methods, ranging from modified traditional film hydration techniques to the novel phase-guided assembly method.