Sensor Letters
·
2016
·Vol. 14
·期 6
·623-629
·
IF 0
Li Liping,Liu Xiaojia,Xiao Qian,Zheng Yizhi,Wang Suiping,Feng Bo
A novel antibody immobilization method was developed for enzyme-linked immunosorbent assay (ELISA). The proposed method utilizes amine-bearing polymer macromolecules, namely, polyamidoamine (PAMAM) or polyethylenimine (PEI) to enhance antibody binding on polystyrene (PS) microwells,
as well as staphylococcal protein A (SPA) to realize orientation immobilization. After carboxylating the PS microwells with the solution of potassium permanganate (KMnO4) in diluted sulfuric acid (H2SO4), the PS surface was activated by 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide
hydrochloride and N-hydroxysuccinimide and then grafted with PAMAM or PEI to introduce free amino groups. Glutaraldehyde was subsequently added to conjugate the amino groups and SPA prior to antibody adsorption. X-ray photoelectron spectroscopy and atomic force microscopy were performed to
investigate the morphology of the PS surfaces before and after different treatments. The immunoglobulin binding sites were confirmed through anti-Fab and anti-Fc ELISA kits. Results from the alpha fetoprotein ELISA kit showed that the use of both PAMAM and SPA is the optimal method for antibody
immobilization. In this treatment, absorbance exhibited an evident gradient with antigen concentrations and reached higher values over 200 ng/mL antigen compared with the ones of other methods.
研究领域:
生物化学
·
分子生物学
·
分析化学
✓ 已验证
DOI
Nano Research
·
2021
·Vol. 15
·期 1
·510-518
·
IF 8.897
Wu Jia-Si,Li Jia-Xian,Shu Na,Duan Qi-Jia,Tong Qi-Song,Zhang Jing-Yang,Huang Yong-Cong,Yang Si-Yu,Zhao Zhi-Bin,Du Jin-Zhi
Tumor associated macrophages (TAMs) tend to exhibit tumor-promoting M2 phenotype and contribute to the development of immunosuppressive microenvironment of solid tumors. Reprograming TAMs from M2 into tumoricidal M1 phenotype is robust for stimulating tumor immunosuppressive microenvironment (TIME). In this study, we developed a poly(amidoamine) (PAMAM) derivative dendrimer (denoted as fourth generation- N,N -diethylaminoethyl (G4-DEEA)) for efficient loading of Toll-like receptor 7 and 8 (TLR7/8) agonist (R848) to remodel the TIME for potent cancer immunotherapy. G4-DEEA exhibited a high loading capacity of R848 up to 35.9 wt% by taking advantage of its dendritic structure. The resulting formulation (designated as G4-DEEA@R848) effectively polarized M2 macrophages into M1 phenotype in vitro , and improved the maturation and activation of antigen-presenting cells. In the 4T1 orthotopic breast cancer model, G4-DEEA@R848 showed a stronger tumor inhibitory effect than free drug. The mechanistic studies suggested that G4-DEEA@R848 could significantly stimulate the TIME by repolarizing TAMs into M1 phenotype, reducing the presence of immunosuppressive myeloid cells and increasing the infiltration of tumor cytotoxic T cells. This study provides a simple but effective dendrimer-based strategy to improve the formulation of R848 for improved cancer immunotherapy.
研究领域:
癌症免疫治疗
·
药学
·
免疫学
✓ 已验证
产品关联
DOI
高影响因子
BIOMACROMOLECULES
·
2022
·
IF 6.978
Zhiyu Yang,Lin Lin,Zhaopei Guo,Xiaoya Guo,Zhaohui Tang,Huayu Tian,Xuesi Chen
The relatively low transfection efficiency limits further application of polymeric gene carriers. It is imperative to exploit a universal and simple strategy to enhance the gene transfection efficiency of polymeric gene carriers. Herein, we prepared a cationic polypeptide poly(γ-aminoethylthiopropyl-l-glutamate) (PALG-MEA, termed PM) with a stable α-helical conformation, which can significantly improve the gene transfection efficiency of cationic polymers. PM can be integrated into polymeric gene delivery systems noncovalently through electrostatic interactions. With the assistance of PM, polymeric gene delivery systems exhibited excellent cellular uptake and endosomal escape, thereby enhancing transfection efficiency. The transfection enhancement effect of PM was applicable to a variety of cationic polymers such as polyethylenimine (PEI), poly-l-lysine (PLL), and polyamidoamine (PAMAM). The ternary gene delivery system PM/pshVEGF/PEI exhibited an excellent antitumor effect against the B16F10 tumor model. Moreover, we demonstrated that PM could also enhance the delivery of gene editing systems (sgRNA-Cas9 plasmids). This work provides a facile and effective strategy for constructing polymeric gene delivery systems with a high transfection efficiency.
研究领域:
遗传学
·
生物医学工程
·
分子生物学
·
基因治疗
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Analytical Methods
·
2025
·
IF 2.6
Zhan Qu,Muhammad Noman Bashir,Miaomiao Wang,Yating Chen,Beenish Noureen,Zhiyao Wang,Yage Liu,Liping Du,Chunsheng Wu
Adenosine triphosphate (ATP) is crucial for cellular activity. The need for ATP detection in the field of biomedicine is on the rapid rise. Several biosensor-based approaches have been developed as a result of the growing demand for ATP detection. An electrolyte-insulator-semiconductor (EIS) sensor is a type of field-effect device that has the ability to detect surface-potential changes with a specific level of sensitivity. In this study, a label-free ATP detection biosensor that is based on poly(amidoamine)-modified EIS sensors was developed, in which ATP-sensitive aptamer (Apt) was utilized as sensitive element and EIS sensor was used as transducer. It is possible to monitor the binding of charged molecules, such as aptamers using EIS sensors in a label-free manner with a straightforward setup. To improve the coupling efficiency of Apt with EIS sensor, positively charged polyelectrolyte, i.e. poly (amidoamine) (PAMAM) dendrimers, was utilized to modify the surface of the EIS sensors to attach the negatively charged Apt based on electrostatic attraction. The adsorptive binding of Apt and ATP results in a change in capacitance of EIS sensor. During the process of surface modification, the electrochemical measurements. of capacitance-voltage (C-V) curves and constant-capacitance (ConCap) characteristics were utilized as indicators for the corresponding processes of EIS sensor surface modification. The measurements results indicated this biosensor was able to detect ATP with high sensitivity and good specificity. The detection range of ATP was 0.1. nM to 100. nM and the detection limit was as low as 0.12 nM. This biosensor has the potential to be utilized in the detection of ATP in the surrounding microenvironment of cells and tissues, which have promising prospects to be applied in the field of biomedicine such as energy and metabolism monitoring of cells and tissues.
研究领域:
生物医学工程
·
分析化学
·
生物传感器
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Stem Cell Research & Therapy
·
2022
·Vol. 13
·期 1
·1-15
·
IF 8.079
Liu Fengyi,Wang Xu,Li Yuzhou,Ren Mingxing,He Ping,Wang Lu,Xu Jie,Yang Sheng,Ji Ping
Background Cartilage defects pose a significant burden on medical treatment, leading to an urgent need to develop regenerative medicine approaches for cartilage repair, such as stem cell therapy. However, the direct injection of stem cells can result in insufficient delivery or inaccurate differentiation. Hence, it is necessary to choose appropriate stem cell delivery scaffolds with high biocompatibility, injectability and chondral differentiation induction ability for cartilage regeneration.Methods In this study, the photocrosslinked gelatin methacrylate (GelMA) hydrogel with high cell affinity and plasticity was selected and strengthened by incorporating methacrylic anhydride-modified poly(amidoamine) (PAMAM-MA) to fabricate an adipose-derived stromal/stem cells (ASCs) delivery scaffold for cartilage repair. The physiochemical properties of the GelMA/PAMAM-MA hydrogel, including the internal structure, stability and mechanical properties, were tested. Then, ASCs were encapsulated into the hydrogels to determine the in vitro and in vivo chondrogenic differentiation induction abilities of the GelMA/PAMAM-MA hydrogel.Results Compared with the GelMA hydrogel, the GelMA/PAMAM-MA hydrogel exhibited more uniform structure, stability and mechanical properties. Moreover, on the basis of good biocompatibility, the hybrid hydrogel was proven to exert a sufficient ability to promote cartilage regeneration by in vitro three-dimensional (3D) culture of rASCs and in vivo articular cartilage defect repair.Conclusion sThe injectable photocrosslinked GelMA/PAMAM-MA hydrogel was proven to be a capable stem cell carrier for cartilage repair and provides new insight into the design strategy of stem cell delivery scaffolds.
研究领域:
再生医学
·
组织工程
·
干细胞生物学
·
生物医学材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanoscale
·
2019
·Vol. 11
·期 42
·20030-20044
·
IF 6.97
Lin Hou,Dandan Chen,Lisha Hao,Chunyu Tian,Yingshan Yan,Ling Zhu,Huijuan Zhang,Yi Zhang,Zhenzhong Zhang
Cancer-associated fibroblasts (CAFs) are important barriers for nanoparticles (NPs) to deeply penetrate into tumors and severely limit the antitumor efficacy of nanomedicines. Herein, we proposed a CAF-triggered transformable drug delivery system based on a cleavable peptide responsive to fibroblast activation protein-α (FAP-α) specifically overexpressed on the surface of CAFs. The NPs were composed of cationic poly(amidoamine) (PAMAM) dendrimers cross-linked by our designed peptide, a chemotherapeutical drug was incorporated onto PAMAM using disulfide bonds and finally, hyaluronic acid (HA) was conjugated to improve the tumor targetability as well as biocompatibility through electrostatic interactions. These NPs had an initial size of ∼200 nm and negative zeta potential favorable for stable blood circulation; however, after docking with CAFs, they dissociated into smaller NPs and exposed the relative positive surface charge to facilitate penetration and enter the tumor cells together with CAFs. An interesting finding was that this system intracellularly released different levels of drugs in these two kinds of cells, which was beneficial for the disruption of the stromal barrier and increasing the local drug accumulation. Our investigation confirmed that the constructed system could alleviate the biological barriers and hold promising therapeutic efficiency for desmoplastic solid tumors.
研究领域:
纳米技术
·
肿瘤学
·
药学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOMATERIALS
·
2024
·
IF 12.8
Qi-Song Tong,Hua Huang,Hui-Han Yu,Rong Liu,Song Shen,Jin-Zhi Du
Remodeling the immunosuppressive tumor microenvironment (TME) by immunomodulators has been well studied in the past years. However, strategies that enable concurrent modulation of both the immunosuppressive TME and tumor-draining lymph nodes (TDLNs) are still in the infancy. Here, we report a pH-sensitive size-switchable nanocluster, SPN-R848, to achieve simultaneous accumulation in tumor and TDLNs for immune activation. SPN-R848 with original size around 150 nm was formed by self-assembly of resiquimod (R848)-conjugated polyamidoamine (PAMAM) derivative, which could disintegrate into its small constituents (～ 8 nm) upon exposure to tumor acidity. The size reduction not only enhanced their accumulation and perfusion in the primary tumor, but promoted their transport and distribution in TDLNs. Accordingly, SPN-R848 remarkably remodeled the immunosuppressive TME by polarizing M2 to M1 macrophages and activated dendritic cells (DCs) in TDLNs, which synergistically facilitated the production and stimulation of cytotoxic T cells, and inhibited tumor growth in breast cancer and melanoma mouse models. Our study suggests that co-activation of immune microenvironments in both tumor and TDLNs may represent a promising direction to elicit strong antitumor immunity.
研究领域:
癌症生物学
·
免疫学
·
纳米技术
·
药学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2020
·Vol. 56
·期 6
·4380-4395
·
IF 3.553
Li Lin,Zhang Peng,Yang Xiucheng,Li Congcong,Guo Yan,Sun Kaoxiang
Abstract A receptor-mediated, active-targeting and glutathione (GSH) turn-on charge-reversal core/shell nanocomplex HA-MEA-s-s-TGA/PAMAM@DOX was constructed to achieve increased stability, improved cellular uptake, facilitated endo-lysosomal escape and enhanced antitumor efficacy. This nanocomplex was composed of anionic hyaluronic acid (HA)-graft GSH-sensitive HA-MEA-s-s-TGA as the outer shell and the cationic PAMAM@DOX core with encapsulated doxorubicin (DOX) into the hydrophobic cavities of polyamidoamine (PAMAM) dendrimers. We hypothesized that the anionic outer layer could promote cellular uptake of HA-MEA-s-s-TGA/PAMAM@DOX by HA receptor-mediated endocytosis. After internalization into tumor cells, the outer shell of the internalized nanocomplex was disassembled in endo-lysosomes via the destruction of disulfide linkages to re-expose PAMAM drug core. This action induced release of the encapsulated DOX and facilitated endo-lysosomal escape through the synergistic action of the proton sponge effect and cationic–anionic interaction between protonated PAMAM and endo-lysosome membranes. In vitro release profiles demonstrated the intracellular environment-responsive release behavior of DOX from this nanocomplex, with a cumulative release of 80% within 4 days in a simulated tumor intracellular microenvironment, whereas the surface charge changed from − 18.82 mV to + 10.95 mV. The MTT assay revealed the good biocompatibility of the negatively charged nanocomplex and efficient toxicity against HeLa cells. The designed pH/GSH dual-responsive nanocomplex could be an efficacious and safe delivery platform for cancer therapy. Graphical abstract
研究领域:
纳米技术
·
药学
·
癌症治疗
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry B
·
2024
·
IF 6.1
Yang Liu,Xiaoting Chen,Xueqin Tan,Yeqian Huang,Wen Zhang,Zhicun Wang,Li Yang,Yunbing Wang,Zhengyong Li,Xingdong Zhang
Microtia profoundly affects patients' appearance and psychological well-being. Tissue engineering ear cartilage scaffolds have emerged as the most promising solution for ear reconstruction. However, constructing tissue engineering ear cartilage scaffolds requires multiple passaging of chondrocytes, resulting in their dedifferentiation and lose their special phenotypes and functions. To tackle these issues, here we employ guanidinobenzoic acid (GBA) modified Generation 5 Polyamidoamine (PAMAM) dendrimers (PG) as Runx1 plasmid carrier to construct PG/pRunx1 polyplex nanoparticles. The PG/pRunx1 polyplexes are transfected into human auricular chondrocytes, significantly mitigating chondrocyte dedifferentiation and enhancing cartilage regeneration during the in vitro culture. Furthermore, we develop a highly porous double-network hydrogels based on methacrylate-functionalized and oxidized chondroitin sulfate and carbohydrazide-modified gelatin and the hydrogels possessed both dynamic adaptability and mechanical support characteristics by reversible dynamic covalent crosslinking and static covalent crosslinking, serving as an ideal scaffold for tissue engineering. Consequently, chondrocytes treated with PG/pRunx1 polyplex nanoparticles are incorporated into the hydrogels to construct tissue-engineered auricular cartilage scaffolds. After subcutaneous implantation in nude mice, the scaffolds containing chondrocytes treated with PG/pRunx1 nanoparticles showed more mature cartilaginous tissue, characterized by prominent ECM deposition and enhanced chondrogenesis. Therefore, this research provides a novel strategy for the development of tissue-engineered auricular cartilage scaffolds.
研究领域:
组织工程
·
再生医学
·
生物材料
·
生物医学工程
·
细胞生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）