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To achieve the painless administration of interferon alpha 1b (rhIFNα-1b), a double-layered soluble polymer microneedle (MN) patch loaded with rhIFNα-1b was used to deliver rhIFNα-1b transdermally. The solution containing rhIFNα-1b was concentrated in the MN tips under negative pressure. The MNs punctured the skin and delivered rhIFNα-1b to the epidermis and dermis. The MN tips implanted in the skin dissolved within 30 min and gradually released rhIFNα-1b. The rhIFNα-1b had a significant inhibitory effect on the abnormal proliferation of fibroblasts and excessive deposition of collagen fibers in the scar tissue. The color and thickness of the scar tissue treated using the MN patches loaded with rhIFNα-1b were effectively reduced. The relative expressions of type I collagen (Collagen I), type III collagen (Collagen III), transforming growth factor beta 1 (TGF-β1), and α-smooth muscle actin (α-SMA) were significantly downregulated in scar tissues. In summary, the MN patch loaded with rhIFNα-1b provided an effective method for the transdermal delivery of rhIFNα-1b.

Coated microneedles (MNs) are widely used for delivering biopharmaceuticals. In this study, a novel gel encapsulated coated MNs (GEC-MNs) was developed. The water-soluble drug coating was encapsulated with sodium alginate (SA) in situ complexation gel. The manufacturing process of GEC-MNs was optimized for mass production. Compared to the water-soluble coated MNs (72.02% ± 11.49%), the drug delivery efficiency of the optimized GEC-MNs (88.42% ± 6.72%) was steadily increased, and this improvement was investigated through in vitro drug release. The sustained-release of BSA was observed in vitro permeation through the skin. The rhIFNα-1b GEC-MNs was confirmed to achieve biosafety and 6-month storage stability. Pharmacokinetics of rhIFNα-1b in GEC-MNs showed a linearly dose-dependent relationship. The AUC of rhIFNα-1b in GEC-MNs (4.51 ng/ml·h) was bioequivalent to the intradermal (ID) injection (5.36 ng/ml·h) and significantly higher than water-soluble coated MNs (3.12 ng/ml·h). The rhIFNα-1b elimination half-life of GEC-MNs, soluble coated MNs, and ID injection was 18.16, 1.44, and 2.53 h, respectively. The complexation-based GEC-MNs have proved to be more efficient, stable, and achieve the sustained-release of water-soluble drug in coating MNs, constituting a high value to biopharmaceutical., Graphical abstract In the coated microneedle produced by the layer-by-layer coating method, the water-soluble drug-containing coating is encapsulated by the complexation-based gel (GEC-MNs). After GEC-MNs are applied to the skin, the release rate of the drug is reduced by the outer layer of the gel. The pharmacokinetic results of rh-IFNα-1b showed that compared with intradermal injection and water-soluble coated microneedles, the sustained release was achieved in GEC-MNs.Image, graphical abstract

Background The impact of biologic aging on immune checkpoint inhibitor (ICI) toxicity and efficacy is underexplored in metastatic melanoma (MM). In peripheral blood T lymphocytes (PBTLs), biologic aging is characterized by changes in T‐cell composition and cellular senescence. Whether indicators of PBTL biologic aging vary in MM patients or can be used to predict premature ICI discontinuation (pID) is unknown. Methods We prospectively collected PBTLs from 117 cancer‐free controls and 46 MM patients scheduled to begin pembrolizumab or nivolumab monotherapy. Seventy‐four mRNAs indicative of T‐cell subset, activation, costimulation/inhibition, and cellular senescence were measured by Nanostring. Relationships between each mRNA and chronologic age were assessed in patients and controls. Candidate biomarkers were identified by calculating the hazard ratio (HR) for pID in patients divided into low and high groups based on log‐transformed mRNA levels or the magnitude by which each mRNA measurement deviated from the control trend (Δage). Area under the curve (AUC) analyses explored the ability of each biomarker to discriminate between patients with and without pID at 6 months and 1 year. Results Fifteen mRNAs correlated with chronologic age in controls, including markers of T‐cell subset, differentiation, cytokine production, and costimulation/inhibition. None of these mRNAs remained correlated with age in patients. Median follow‐up was 94.8 (1.6‐195.7) weeks and 35 of 46 patients discontinued therapy (23 progression, seven toxicity, and five comorbidity/patient preference). Elevated pretherapy CD8A (HR = 2.2 [1.1‐4.9]), CD45RB (HR = 2.9 [1.4‐5.8]), and TNFRSF14 (HR = 2.2 [1.1‐4.5]) levels predicted pID independent of Δage‐correction. CD3ε, CD27, and FOXO1 predicted pID only after Δage‐correction (HR = 2.5 [1.3‐5.1]; 3.7 [1.8‐7.8]; 2.1 [1.1‐4.3]). AUC analysis identified Δage‐CD3ε and Δage‐CD27 as candidate predictors of pID (AUC = .73 and .75). Conclusions Correlations between transcriptional markers of PBTL composition and chronologic age are disrupted in MM. Correcting for normal, age‐related trends in biomarker expression unveils new biomarker candidates predictive of ICI outcomes.

This study reported a method for quickly detecting the moisture sorption of microneedle materials to predict the dissolving properties of the materials, and the flexibility of the microneedle mater...

This study reported novel long-acting microneedles (MNs) that can be implanted into the skin in situ quickly. It was prepared to entrap a model drug in the biodegradable poly(lactide-co-glycolide) (PLGA) needle tips by a controllable casting-mold technique, avoiding the effect of high temperature melting the drug stability. The third-generation progesterone etonogestrel (ENG) was selected as the model drug. A new preparing method of MNs was proposed by using N-methyl pyrrolidinone as a solvent for needle tip matrix with good biocompatibility and safety. After solidified at 70°C for 4 h, the needle tips were strong enough to puncture the skin. ENG could crystallize uniformly in needle tips, observed by a polarizing microscope. The intradermal implantation ratio of the MNs was affected by the parameters of needle shape and needle spacing. With optimization of MN formulations, the drug loading capacity was 153.0 ± 13.5 μg, and the drug utilization rate was up to 92.6 ± 8.1%. In rats, the pharmacokinetic study of the implantable MNs showed that the plasma ENG level could be detectable until 336 h and the AUC0→48h only accounted for 37.8% of AUC0→∞. Therefore, this developed intradermal implantable MNs could provide a minimally invasive sustained-release system suitable for self-administration.

How the measurement of aging biomarkers in peripheral blood T-lymphocytes (PBTLs) is influenced by cell composition is unclear. Here, we collected peripheral blood and isolated CD3+ PBTLs from 117 healthy couples between the ages of 21 and 72. Each sample was profiled for Horvath epigenetic clock (DNAm), p16INK4a expression, cytomegalovirus (CMV) seropositivity and 74 mRNA markers of PBTL subtype, differentiation, immune checkpoints, and cytokine production. Correlations between individual aging biomarkers (DNAm or p16INK4a) and PBTL mRNAs were corrected for chronological age, sex, and couple. DNAm measurements correlated with CMV seropositivity as well as PBTL mRNAs indicative of effector function (CD8A, EOMES, TBX21, GZMB), poor proliferative capacity (KLRG1, CD57), differentiation (CD45RO, CD45RA), and immune checkpoints (PDCD1, TIGIT, LAG3, CD160, CD244). In contrast, only three PBTL mRNAs, CD28, CD244, and p14ARF, showed a significant association with p16INK4a. p16INK4a expression also showed a weaker association with immunosenescent PBTL subsets than DNAm in flow cytometry analyses. These data suggest that PBTL composition has a greater influence on DNAm than p16INK4a and link accelerated epigenetic aging to immunosenescent phenotypes.

Autologous stem cell transplant (ASCT) is the standard of care for patients with multiple myeloma (MM). The clinical significance of peripheral blood T lymphocyte (PBTL) immunologic changes associated with ASCT is poorly understood. Here we evaluated T cell transcriptional messenger RNA profiles and immunophenotypes to correlate immunologic senescence, exhaustion, and anergy with clinical endpoints in a cohort of patients with MM undergoing ASCT. ASCT induced global transcriptional T cell changes and altered molecular levels of markers of T cell subtypes, T cell activation, and exhaustion. These included reduced CD4/CD8 ratio, skewing toward the Th1 subset, reduced expression of costimulatory receptors CD27 and CD28, heightened T cell activation, and increased expression of immune modulatory molecules LAG3 and PD1. Multicolor flow cytometry experiments confirmed altered circulating CD4 and CD8 subsets and skewing toward differentiated effector cells. Moreover, ASCT promoted an exhausted immunophenotype in CD3+CD4+ subsets and a senescent immunophenotype in CD3+CD8+ subsets. Subset-specific altered expression was also seen for surface molecules with immunomodulatory function. ASCT affected soluble levels of molecules with immunomodulatory function by increasing plasma HVEM and TIM3. High molecular LAG3 level was associated with inferior event-free survival post-ASCT (hazard ratio=5.44; confidence interval, 1.92 to 15.46; P = .001; adjusted P [controlling for false discovery rate] = .038). Using a comprehensive evaluation of PBTLs on a molecular and phenotypic level, we have identified that ASCT induces global T cell alterations with CD4 and CD8 subset-specific changes. Moreover, LAG3 emerged as an early biomarker of adverse events post-ASCT. These findings will support the development of treatment strategies targeting immune defects in MM to augment or restore T cell responses.

We describe a swellable microneedle (SMN) consisting of Ca

To facilitate the storage and use of poly (lactic-co-glycolic acid) (PLGA)-based microneedles (MNs) in hot seasons and regions, thermally stable MNs loaded with levonorgestrel (LNG) were developed. Due to its good biocompatibility and high glass transition temperature (Tg), Hydroxypropyl methylcellulose (HPMC) was added to the PLGA-based MNs to increase thermal stability. MNs with HPMC exhibited excellent thermal stability at high temperatures. After the MNs has been applied to the skin for 10 min, the backing layer of the MNs was dissolved by contact with the interstitial fluid of skin, which resulted in the separation of the MN tips from the backing layer. The MN tips were implanted intradermally and sustained-release LNG. Biodegradable polymers were used to encapsulate the LNG, providing long-acting contraception. The in vitro release rate of LNG from the MNs reached 72.78%-83.76% within 21 days. In rats, the MNs maintained plasma concentrations of LNG above the human contraceptive level for 8–12 days. In mice, the time required for complete degradation of the MN tips was 12–16 days. MNs have excellent medication adherence due to the advantages of painlessness, minimally invasive, and self-administered. MNs can make long-acting contraceptives more readily available to humans.

Staphylococcal enterotoxin B (SEB) produced by the Staphylococcus aureus bacteriumis most commonly associated with food poisoning and is known to also cause toxic shock syndrome. Currently, no approved vaccine or specific drug is available to treat SEB intoxication. In this study, we fabricated dissolving microneedles (MNs) loaded with recombinant SEB (rSEB) protein, and evaluated its characteristics, including dissolution profile, protein particle size, insertion depth, antigen retention time in vivo, and skin irritation. Our results showed that rSEB protein-loaded dissolving MNs made of chondroitin sulfate (2%) and trehalose (0.8%) could easily penetrate into the mouse skin within 5 min. The rSEB particle size was unchanged before and after MN fabrication. The skin penetration depth of the MNs was 260 µm. Moreover, the MNs also significantly extended the antigen retention time in vivo. rSEB protein-loaded dissolving MNs also triggered slight erythema at the beginning of administration, but this erythema disappeared within a few hours. More importantly, we investigated the immunogenicity and protective efficacy of rSEB protein-loaded dissolving MNs. Challenge studies in mice revealed that mice in full-dose MN group had a high level of SEB specific antibody response thatprovided100% protection against a lethal SEB toxin challenge. However, there was only 60% protection observed in mice that were in the half-dose MN (dose sparing) group. We also determined the pathological alterations in the tissues of the immunized mice. Taken together, these dissolving MNs may present a promising transcutaneous immunization strategy for treating SEB intoxication.

We previously reported that genetic deletion of β-catenin in mouse corneal keratocytes resulted in precocious corneal epithelial stratification. In this study, to strengthen the notion that corneal keratocyte-derived Wnt/β-catenin signaling regulates corneal epithelial stratification during mouse development, we examined the consequence of conditional overexpression of a stabilized β-catenin mutant (Ctnnb1ΔE3) in corneal keratocytes via a doxycycline (Dox)-inducible compound transgenic mouse strain. Histological analysis showed that conditional overexpression of Ctnnb1ΔE3 in keratocytes inhibited corneal epithelial stratification during postnatal development. Unlike the corneal epithelium of the littermate controls, which consisted of 5-6 cell layers at postnatal day 21 (P21), the mutant corneal epithelium contained 1-2 or 2-3 cell layers after Dox induction from embryonic day 0 (E0) to P21 and from E9 to P21, respectively. X-gal staining revealed that Wnt/β-catenin signaling activity was significantly elevated in the corneal keratocytes of the Dox-induced mutant mice, compared to the littermate controls. Furthermore, RT-qPCR and immunostaining data indicated that the expression of Bmp4 and ΔNp63 was downregulated in the mutant corneas, which was associated with reduced corneal epithelial proliferation in mutant epithelium, as revealed by immunofluorescent staining. However, the expression of Krt12, Krt14 and Pax6 in the mutant corneas was not altered after overexpression of Ctnnb1ΔE3 mutant protein in corneal keratocytes. Overall, mutant β-catenin accumulation in the corneal keratocytes inhibited corneal epithelial stratification probably through downregulation of Bmp4 and ΔNp63 in the corneal epithelium.

To overcome the poor solubility, skin irritation, and low permeability of azelaic acid (AZA) existed on the marketed formulations, a co-drug principle via matrine (MAT) was adopted to prepare anti-acne dissolving microneedles (DMNs). The formula was optimized according to the solubility and antibacterial activity of novel ionic salt. The results indicated solubilization of AZA could be achieved at a molar ratio between AZA and MAT was 1:1. Meanwhile, synergistic antibacterial and anti-irritative properties were acquired. The matrix materials were composed of sodium carboxymethyl cellulose (CMC), polyvinylpyrrolidone (PVP), and trehalose. And drug loadings of AZA and MAT in DMNs were 201.88 ± 4.81 µg and 259.71 ± 1.72 µg, respectively. After insertion into porcine skin for 10 h, the cumulative permeability of AZA and MAT were 68.16% ± 3.79% and 57.37 ± 5.17%, respectively, while just 4.13 ± 0.39% (p < 0.01) was detected for commercially available AZA gel. In vitro antibacterial experiment, bacteriostatic rates of DMNs were all above 95% for Staphylococcus aureus, Staphylococcus epidermidis, and Propionibacterium acnes. Besides, DMNs exhibited no cytotoxicity and skin irritation. In conclusion, combination between AZA and MAT addressed shortcomings of AZA, and made it easier, safer, and more effective in acne treatment.

The study design is that lipophilic drug was encapsulated within dissolving microneedles (DMNs) for sustained-release delivery over 1 week. Etonogestrel (ENG), the progestogen used in hormonal contraceptives, was loaded in 2-layered DMNs in the form of microcrystal particles (MPs). In vitro release study indicated that ENG in the MP form could sustain drug release compared to noncrystal form. Hydroxypropyl methylcellulose and polyvinyl alcohol were used to prepare the fast dissolving needle tips and flexible back layer, respectively. The mechanical strength of microneedles was not affected even with the drug-loading efficiency of 50.0% in needle tips. The penetration depth of DMNs in skin, observed using a confocal laser scanning microscope, was approximately 280 μm. The tips of DMNs could be dissolved in rat skin within 1 h with a drug delivery efficiency of 63.8 ± 2.0%. The pharmacokinetic study of DMN treatment in rats showed that the plasma levels of ENG were a dose-dependent profile and were much steadier than intradermal (ID) injections. There was no statistical difference between bioavailability of ENG treated with DMNs or ID injections ( p >0.05). Therefore, the novel DMNs loaded with drug MP provided a potential minimally invasive route for ID sustained delivery of lipophilic drug.

This work reports the synthesis of a novel copolymer, poly(AA-PBA-PAA) via an easy one-pot method, the fabrication of boronic acid containing surface layer on silicon chip, and the sandwich immunoassay using magnetic nanoparticles (MNPs) as signal label for fast determination of HbA1c. Poly(AA-PBA-PAA) was synthesized with acrylic acid (AA), 3-aminophenylboronic acid (APBA) and 4-Aminobenzylamine (APAA) by EDC/NHS amidation and RAFT. The molecule structure and molecule weight of the poly(AA-PBA-PAA) were characterized by nuclear magnetic resonance spectroscopy (1H NMR), fourier transform infrared spectroscopy (FT-IR) and gel permeation chromatography (GPC). The presence of aniline residues allowed the copolymer covalently immobilizing on polystyrene grafted maleic anhydride (PS-MA) coating. We also confirmed the sandwich structure of boronic acid affinity immunoreaction spot on optical microscope and optical profiler. By the means of magnetic nanoparticles counting, a linear range between 0.1–10 μg mL−1 was achieved for the determination of HbA1c. This strategy possesses high sensitivity with detection limit of 17.7 ng mL−1 and excellent stability at 4 °C. The repeatability is evaluated with CV values less than 5% for 10 magnetic nanoparticle number calibrations on the same chip, and less than 10% for 10 different batches. Finally, a comparison of THb and HbA1c determination with different eluents demonstrates significant specificity of this method.

The aim of this study was to prepare dissolving microneedles (DMNs) patches containing tranexamic acid (TA) for the treatment of melasma. Polyvinyl alcohol (PVA) and polyvinylpyrrolidone (PVP) were preferred as matrix materials through the compatibility experiment. In the in vitro permeation study, the transdermal amount of TA was significantly promoted through dissolving microneedles with the cumulative release was 44.43 ± 6.55%. By comparison, the release of TA solution assisted with solid microneedles (SMNs) was merely 11.31 ± 2.30% (p 0.05). Pharmacokinetics study indicated the bioavailability of dissolving microneedles was more than 1.3 times compared with oral administration. In pharmacodynamics investigation, TA dissolving microneedles obviously reduced melanin deposition in the skin of melasma guinea pigs after 8 consecutive administrations. In particular, the combination of tranexamic acid and licorice extract (LIC) dissolving microneedles worked better than tranexamic acid alone. Accelerated stress conditions including high temperature, high humidity, as well as photostability were designed to prove that TA microneedles maintained good pharmaceutical stability. In conclusion, tranexamic acid dissolving microneedles showed reliable quality and remarkable effect. Moreover, the combination of tranexamic acid and licorice extract had a synergistic therapy in melasma.

The dermal and transdermal delivery of protein pharmaceuticals faces enormous challenges, and at the same time, has very significant potential for the non-invasive treatment of both localized and systemic diseases. To demonstrate the pharmaceutical usefulness of dissolving microneedles (MNs) containing interferon-α-2b (IFN), IFN MNs were prepared using a new method. IFN were encapsulated in MNs with dose from 4.94 ± 0.64 to 23.79 ± 2.48 μg, and in vitro release test showed the efficiency reached 49.2%. After percutaneous administration of IFN MNs to rats, serum IFN levels were measured for 12 h. The peak serum IFN level, maximum drug concentration (Cmax), and the time to reach maximum concentration (Tmax), were 11.58 ± ng/ml and 40 min, respectively, for high-dose MNs group. The area under the curve (AUC) of MNs group was 28.85 ng·h/ml, while intramuscular injection (IM) group with equal dose was 31.17 ng·h/ml. Immunogenicity analysis showed the anti-IFN antibody got back to normal level at ninth week, and there was no difference between male and female rats. IFN MNs showed good stability for 2 months and no damage to the administered rats' skin. The results demonstrated the IFN MNs have a great potential to provide an alternative to IM.

The development of organs with an epithelial parenchyma relies on reciprocal mesenchymal-epithelial communication. Mouse corneal epithelium stratification is the consequence of a coordinated developmental process based on mesenchymal-epithelial interactions. The molecular mechanism underlying these interactions remains unclear. The Wnt/β-catenin signaling pathway is involved in fundamental aspects of development through the regulation of various growth factors. Here, we show that conditional ablation of either β-catenin (Ctnnb1cKO) or co-receptors Lrp5/6 (Lrp5/6cKO) in corneal stromal cells results in precocious stratification of the corneal epithelium. By contrast, ectopic expression of a murine Ctnnb1 gain-of-function mutant (Ctnnb1cGOF) retards corneal epithelium stratification. We also discovered that Bmp4 is upregulated in the absence of β-catenin in keratocytes, which further triggers ERK1/2 (Mapk3/1) and Smad1/5 phosphorylation and enhances transcription factor p63 (Trp63) expression in mouse corneal basal epithelial cells and in a human corneal epithelial cell line (HTCE). Interestingly, mouse neonates given a subconjunctival BMP4 injection displayed a phenotype resembling that of Ctnnb1cKO. Conditional ablation of Bmp4 eradicates the phenotype produced in Ctnnb1cKO mice. Furthermore, ChIP and promoter-luciferase assays show that β-catenin binds to and suppresses Bmp4 promoter activity. These data support the concept that cross-talk between the Wnt/β-catenin/Bmp4 axis (in the stromal mesenchyme) and Bmp4/p63 signaling (in the epithelium) plays a pivotal role in epithelial stratification during corneal morphogenesis.

Hydrophobic drugs wrapped in poly (lactic-co-glycolic acid) (PLGA)-based microneedles (MNs) require a long time to release completely. To obtain the desired duration, it is still necessary to modulate the release of hydrophobic drugs from MNs, while the PLGA composition is unchangeable. In this work, implantable PLGA microneedles (IPMNs) composed of PLGA arrowheads encapsulating levonorgestrel (LNG) and a water-soluble supporting array were designed. We explored trehalose used as a porogen on the release of hydrophobic LNG from PLGA-based MNs. Varying the trehalose content in PLGA arrowheads could induce different rates of drug release. The highest cumulative release of LNG was 76.2 &plusmn, 3.9% for IPMNs with 33.3% trehalose during 21 days in vitro, while the cumulative release of LNG was 60.4 &plusmn, 3.5% for IPMNs without trehalose. Pharmacokinetic results in rats showed that plasma levels of LNG were sustained for 13 days for IPMNs with 33.3% trehalose and 16 days for IPMNs without trehalose. Furthermore, the PLGA arrowheads with trehalose degraded more rapidly than those without trehalose over 21 days in rats. Consequently, using trehalose as a porogen was a feasible approach to modulate the release of a hydrophobic drug from PLGA-based MNs.

Swellable microneedles (SMNs) are made of hydrogels and can deliver drug with controlled delivery rate by the cross-link density of the hydrogel. In this study, an acryl resin-based SMNs was developed for poorly water-soluble drugs. The making process of the SMNs is very simple and only need 60 min. The SMNs has high mechanical strength and is not easily broken. In-vitro release of SMNs-loaded model drug, granisetron base (GRB), was investigated. The results showed that seven days controlled release of GRB was obtained when SMNs contained pore-foaming agents (1.5% dicalcium phosphate (CaHPO

DNA vaccines are simple to produce and can generate strong cellular and humoral immune response, making them attractive vaccine candidates. However, a major shortcoming of DNA vaccines is their poor immunogenicity when administered intramuscularly. Transcutaneous immunization (TCI) via microneedles is a promising alternative delivery route to enhance the vaccination efficacy. A novel dissolving microneedle array (DMA)-based TCI system loaded with cationic liposomes encapsulated with hepatitis B DNA vaccine and adjuvant CpG ODN was developed and characterized. The pGFP expression in mouse skin using DMA was imaged over time. In vivo immunity tests in mice were performed to observe the capability of DMA to induce immune response after delivery of DNA. The results showed that pGFP could be delivered into skin by DMA and expressed in skin. Further, the amount of expressed GFP was likely to peak at day 4. The immunity tests showed that the DMA-based DNA vaccination could induce effective immune response. CpG ODN significantly improved the immune response and achieved the shift of immune type from predominate Th2 type to a balance Th1/Th2 type. The cationic liposomes could further improve the immunogenicity of DNA vaccine. In conclusion, the novel DMA-based TCI system can effectively deliver hepatitis B DNA vaccine into skin, inducing effective immune response and change the immune type by adjuvant CpG ODN.

Transcutaneous immunization (TCI) has many advantages compared with needle-based administrations. But the conventional TCI shows poor permeation of antigens across the skin barrier. In this study, Functional MicroArray (FMA) system was used to poke the skin and increase the permeability, and the hydrogel patch formulation was used as the carrier for transdermal delivery of hepatitis B surface antigen (HBsAg) and cholera toxin B (CTB) as an adjuvant. In vitro permeation of antigen was studied using porcine ear skin and rat abdominal skin. The results showed that FMA system could significantly increase the permeation of HBsAg across skin compared with conventional TCI. HBsAg loaded hydrogel formulation exhibited better antigenic thermostability than the liquid formulation. In vivo immunization studies were performed in mice, and the serum IgG titer, IgG2a/IgG1 ratio were measured. The results showed that TCI with FMA induced more potent immune responses than the groups without FMA pretreatment. CTB adjuvanted TCI group could induce higher IgG titers compared with the group without CTB. Furthermore, TCI group can maintain a longer duration of stable IgG titers compared with the intramuscular injection (IM) group. In conclusion, the FMA/hydrogel system was proved to be a potential vaccination strategy against hepatitis B virus.

A lyophilized hydrogel patch system was developed for microneedle-mediated insulin delivery. The matrix of Cross-linked poly(acrylamide-co-acrylic acid) were synthesized by precipitation polymerization. Recombinant human Insulin was loaded into the lyophilized polymer matrix, which can be rehydrated by water. After the hydrated patch was applied to the abdominal skin of diabetic rats after microneedle pretreatment, pharmacodynamics and pharmacokinetics evaluation was performed. The blood samples were collected to monitor blood glucose and serum insulin levels for 12 h. Blood glucose was lowered in proportion to the concentration of insulin loaded in lyophilized hydrogel patches (R(2)=0.99), with a longer duration of action compared to subcutaneous injection. Stability study confirmed more than 90% of insulin activity was retained in lyophilized hydrogel after 6 months of storage at 4 °C. In conclusion, hydrogel patches were demonstrated to be appropriate drug reservoir for sustained release of insulin with microneedle mediated transdermal delivery.

Insulin delivery relies on subcutaneous or intravascular injection, leading to reduced patient compliance. Transdermal delivery of insulin has been successfully demonstrated but dose accuracy and skin irritation are problematic in addition to the complex basal-bolus delivery profile required by insulin therapy. Here we present a novel intraepidermal delivery technology (delivered site at epidermis layer,150 μm) by combining skin pretreatment with short microneedles (150 μm in length) and iontophoresis transdermal patch (enhanced transport via electrical field) that can provide a continuous basal dose and on-demand bolus dosing for mealtime insulin needs. To our knowledge, this is the first demonstration of therapeutic equivalence between fast-acting human regular insulin and long-acting insulin with possibilities for on-demand dose adjustment. This new intraepidermal delivery technology is likely to change the therapy regimen of patients suffering from insulin-dependent diabetes mellitus and provide a way to lower cost in comparison with insulin pumps and improve patient compliance.The authors present a novel intraepidermal insulin delivery technology by combining skin pretreatment with short microneedles and iontophoresis transdermal patch to provide a continuous basal dose and on-demand bolus dosing. This new method is has the potentials to replace insulin pumps by offering a cost effective alternative with less inconvenience and improved compliance.

Dissolving microneedles (DMNs) based transdermal delivery is an attractive drug delivery approach with minimal invasion. However, it is still challenging to load poorly water-soluble drugs in DMNs for systemic delivery. The aim of the study was to develop DMNs loaded with artemether (ARM) as a model drug, to enable efficient drug penetration through skin for systemic absorption and distribution. The micro-conduits created by microneedles were imaged by confocal laser scanning microscopy (CLSM), and the insertion depth was suggested to be about 270μm. The maximum amount of ARM delivered into skin was 72.67±2.69% of the initial dose loaded on DMNs preparation. Pharmacokinetics study in rats indicated a dose-dependent profile of plasma ARM concentrations, after ARM-loaded DMNs treatment. In contrast to intramuscular injection, DMNs application resulted in lower peak plasma levels, but higher plasma ARM concentration at 8h after administration. There were no significant difference in area under the curve and bioavailability between DMNs group and intramuscular group (P>0.05). Pharmacodynamics studies performed in collagen-induced arthritis (CIA) rats showed that ARM-loaded DMNs could reverse paw edema, similar to ARM intramuscular injection. In conclusion, developed DMNs provided a potential minimally invasive route for systemic delivery of poorly water-soluble drugs.

e21578Background: Senescence is an irreversible cell cycle arrest associated with sustained p16INK4a (p16) expression and biological aging. The inability of senescent cells to proliferate suggests ...

An intradermal microdelivery system comprising a wafer having 150-mum long microneedles and an applicator was used for controlled release of insulin. Insulin was topically applied on microneedle-pretreated skin. In vitro percutaneous studies showed that the penetration amount of FITC-Insulin following microneedle pretreatment was enhanced significantly and continued to increase for several hours after the removal of donor phase. In vivo studies on diabetic rats confirmed that the pharmacodynamic profile of percutaneously administrated regular insulin was smooth, with the duration of action comparable to that of subcutaneously injected biphasic insulin. The effects of insulin concentration, duration and area of microneedle treatment on blood glucose lowering were studied in vivo. The results indicated that the duration of microneedle treatment and insulin concentration were key influencing factors to optimize blood glucose control. The extent of blood glucose lowering was in proportion to the area of microneedle treatment.

There is a significant interest in the application of microneedles in intradermal drug delivery systems. Previous studies have demonstrated that skin permeation of drugs can be increased by orders of magnitude with microneedle insertion. In this study, emphasis is placed on the development of low cost, painless intradermal microneedle systems that can enhance the percutaneous drug permeation. Microneedles of octagonal pyramidal shape with the length of 150 mum were employed, and the capabilities of skin permeation enhancement under different delivery conditions were examined. The delivery parameters taken into account included the insertion time and the area of insertion. It was found that when solid microneedle arrays of 150 mum in length were pierced into human dermatomed skin for 5 to 60 s, microconduits with the depth of 50 to 80 mum were created to facilitate the percutaneous permeation of drugs. In percutaneous tests, it was demonstrated that the permeability coefficient of calcein (MW = 622.55) was significantly increased by 10(4) to 10(5) times compared to that on intact skin. In terms of biocompatibility, biological evaluation indicated a broad spectrum of safety for the microneedle system. These results suggest that the octagonal pyramidal microneedles can be an effective tool in developing novel intradermal drug delivery system.

Nickel complexes 1–4 ligated with 2,9-disubstituted-1,10-phenanthroline were synthesized and characterized by FT-IR spectra and elemental analysis. The molecular structure of complex 2 was confirmed by X-ray crystal diffraction analysis. Activated with methylaluminoxane (MAO), those complexes showed moderate activities for ethylene oligomerization.

The nickel complexes are of special relevance to catalysis for ethylene oligomerization and polymerization. Beyond the famous commercial SHOP process for ethylene oligomerization, among recent progress of nickel catalysts, various nickel complexes containing different ligands such as the bidentate and tridentate ligands are of interest. In contrast to the importance of hetereogeneous catalysis, the homogeneous catalyst is a small share for polyolefins, while the well-defined complexes affect the microstructure of the resultant polyolefin. The nickel catalysts often perform ethylene activations for inner olefins and the branched polyethylene with broad or bimodal molecular weight distribution. The catalytic behavior will be affected by adaptation of ligands coordinating around the nickel center. In addition, the auxiliary ligand Ph3P can improve the catalytic activity by one order of magnitude, and its active center can be confirmed through isolating and characterizing the reliable intermediate.

A novel functionalised copolymer with three polymeric components, poly(ethylene glycol)-block-poly(aspartic acid-stat-phenylalanine), PEG-P(asp-phe), was synthesised and investigated for its potential to form micelles via ionic interactions with a model water-soluble drug, diminazene aceturate. Drug-free solutions of structurally related PEG-P(asp-phe) 5:6:4 and PEG-P(asp-phe) 5:4:6 copolymers indicated polymeric aggregation into micellar-type constructs. The size of PEG-P(asp-phe) 5:6:4 micelles was found to be pH and drug content-dependent. The drug-loaded systems existed as discreet units and were fairly uniform in size and shape. More drug could be included in the PEG-P(asp-phe) 5:6:4 micelles as compared to if only interaction with carboxyl groups from aspartic acid units was responsible for micelle formation, indicating the augmentative role of phenylalanine moieties in drug-incorporation. The slower in vitro drug release from PEG-P(asp-phe) 5:6:4 micelles as compared to PEG-Pasp (AB) micelles indicated the role of the phenylalanine moiety in controlling drug release. This study, therefore, confirmed the potential of a novel tri-component copolymer structure, PEG-P(asp-phe), for the formation of polyionic micelles for drug delivery.

The objective of the present study is to compare the immunogenicity of insulin by microneedle-mediated intradermal delivery or subcutaneous injection. Female and male rats were treated with insulin by either microneedle-mediated intradermal delivery or subcutaneous injection twice a week for 4 weeks. A control group without insulin administration was also studied. Human anti-insulin antibody (AIA) levels were measured by radioimmunoassay (RIA) before starting insulin treatment and after that within 20 weeks. The male rats did not induce positive AIA levels, and there was no significant difference between all male groups. In contrast, in female rats the AIA levels were significantly higher in microneedle group compared with injection group, and lasted from 6 to 20 weeks after starting insulin treatment. The increased immunogenicity of insulin delivery by microneedle might be due to the large number of immune cells in skin.

Coated microneedles have been paid much attention recently, and several coating strategies have been developed to address the problems during coating process. However, there are still some unresolved issues, such as, precise control requirements, microneedle substrate contamination and high processing temperature. The purpose of this study was to develop a simple and controllable method to make uniform coatings on microneedles at room temperature. This novel method avoids the contamination of microneedle substrate by providing both the adsorption force of thickener and micro-scale coating film produced by a newly design device. Thickeners were screened to enhance the mass of coatings. The parameters that influence the coatings were tested systematically, which made coating process controllable. Finally, three model drugs were coated onto microneedles to prove the method is applicable more broadly. In addition, insertion experiments were carried out to test the drug delivery feasibility of the coated microneedles. In conclusion, this study presents a simple and controllable method to coat microneedles with small molecular chemical drugs or large proteins for rapid skin drug delivery.

National Natural Science foundation of China [11274321, 11404349, 51502314, 51522105, 11374312]; Key Research Program of the Chinese Academy of Sciences [KJZD-EW-M05]; U.S. National Science Foundation [ECCS-1404542]