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1.
J Orthop Surg Res ; 19(1): 315, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38807173

RESUMO

BACKGROUND: The impact of anatomical factors, such as the lateral tibial slope (LTS), on outcomes following anterior cruciate ligament (ACL) reconstruction is an area of growing interest. This study was led by the observation that patients with a higher LTS may have different recovery trajectories. HYPOTHESIS/PURPOSE: The purpose of this study was to investigate the correlation between a higher LTS and long term subjective outcomes following single-bundle ACL reconstruction. STUDY DESIGN: This study was designed as a retrospective cohort study. METHODS: The study comprised 138 patients who underwent single-bundle ACL reconstruction. The LTS was measured on preoperative radiographs. Patient-reported outcome measures (PROMs) were collected, which included the Lysholm Knee Score, UCLA Activity Score, IKDC Score, and Tegner Activity Score, over a mean follow-up duration of 137 months. RESULTS: A significant negative correlation was found between LTS and all measured PROMs (p < 0.001). The established cut-off value of LTS distinguishing between "Good" and "Fair" Lysholm scores was 8.35 degrees. Female patients have statistically significant higher LTS and lower PROMs scores than male. Patients with LTS greater than or equal to 8.35 had significantly lower PROMs, indicative of poorer functional and subjective outcomes. CONCLUSION: Our findings suggest that a higher LTS is associated with inferior subjective outcomes following single-bundle ACL reconstruction in long term. The LTS cut-off value of 8.35 degrees could potentially be used as a reference in preoperative planning and patient counseling. CLINICAL RELEVANCE: Understanding the relationship between LTS and ACL reconstruction outcomes could inform surgical planning and postoperative management. These findings highlight the need to consider anatomical variances, such as LTS, when assessing patient-specific risks and recovery expectations, contributing to the advancement of personalized care in sports medicine.


Assuntos
Reconstrução do Ligamento Cruzado Anterior , Medidas de Resultados Relatados pelo Paciente , Tíbia , Humanos , Reconstrução do Ligamento Cruzado Anterior/métodos , Masculino , Feminino , Estudos Retrospectivos , Adulto , Tíbia/cirurgia , Tíbia/diagnóstico por imagem , Adulto Jovem , Resultado do Tratamento , Adolescente , Lesões do Ligamento Cruzado Anterior/cirurgia , Lesões do Ligamento Cruzado Anterior/diagnóstico por imagem , Pessoa de Meia-Idade , Estudos de Coortes , Seguimentos , Fatores de Tempo
2.
Arch Orthop Trauma Surg ; 144(2): 619-626, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37962635

RESUMO

PURPOSE: To determine if there is a correlation between lateral tibial slope and long-term clinical results in patients who underwent double-bundle ACL reconstruction. METHODS: We retrospectively reviewed patients that received double-bundle ACL reconstruction at a single institution by a single surgeon from January 2011 to December 2014. All the magnetic resonance imaging were reviewed and lateral tibial slopes (LTS) were recorded by an experienced surgeon and rechecked by the other two authors of this study that specialized in orthopedic knee surgery. The relationship between PROMs measurement and lateral tibial slope were analyzed. The patients were then separated into two groups (LTS > 7.4° and < 7.4°) according to the previous study. RESULTS: A total of 119 patients were enrolled in this study. All enrolled patients were followed for at least 8 years. The PROMS result were negatively correlated with the lateral tibial slope (p values all < 0.001). The patients with high lateral tibial slope had significantly lower PROMS values (Lysholm 94.26 ± 5.61 vs 80.15 ± 8.28, p = 0.013; IKDC 82.99 ± 4.55 vs 70.09 ± 7.15, p = 0.003; Tegner 9.32 ± 0.95 vs 6.85 ± 1.99, p < 0.001). Finally, the LTS cutoff value between patients with "Good" and "Fair" Lysholm score in our study was 7.55 degrees. CONCLUSIONS: Patients with high lateral tibial slope may result in inferior long-term subjective outcomes. The using of double-bundle ACL reconstruction along cannot overcome the negative impact caused by steep lateral tibial slope. A lateral tibial slope of 7.55° may be used as a cut-off for a good clinical outcome. LEVEL OF EVIDENCE: III retrospective comparative prognostic trial.


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Humanos , Estudos Retrospectivos , Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior/métodos , Articulação do Joelho/cirurgia , Tíbia/cirurgia
3.
J Biomed Sci ; 30(1): 35, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37259079

RESUMO

BACKGROUND: Cancer-specific adoptive T cell therapy has achieved successful milestones in multiple clinical treatments. However, the commercial production of cancer-specific T cells is often hampered by laborious cell culture procedures, the concern of retrovirus-based gene transfection, or insufficient T cell purity. METHODS: In this study, we developed a non-genetic engineering technology for rapidly manufacturing a large amount of cancer-specific T cells by utilizing a unique anti-cancer/anti-CD3 bispecific antibody (BsAb) to directly culture human peripheral blood mononuclear cells (PBMCs). The anti-CD3 moiety of the BsAb bound to the T cell surface and stimulated the differentiation and proliferation of T cells in PBMCs. The anti-cancer moiety of the BsAb provided these BsAb-armed T cells with the cancer-targeting ability, which transformed the naïve T cells into cancer-specific BsAb-armed T cells. RESULTS: With this technology, a large amount of cancer-specific BsAb-armed T cells can be rapidly generated with a purity of over 90% in 7 days. These BsAb-armed T cells efficiently accumulated at the tumor site both in vitro and in vivo. Cytotoxins (perforin and granzyme) and cytokines (TNF-α and IFN-γ) were dramatically released from the BsAb-armed T cells after engaging cancer cells, resulting in a remarkable anti-cancer efficacy. Notably, the BsAb-armed T cells did not cause obvious cytokine release syndrome or tissue toxicity in SCID mice bearing human tumors. CONCLUSIONS: Collectively, the BsAb-armed T cell technology represents a simple, time-saving, and highly safe method to generate highly pure cancer-specific effector T cells, thereby providing an affordable T cell immunotherapy to patients.


Assuntos
Anticorpos Biespecíficos , Antineoplásicos , Neoplasias , Camundongos , Animais , Humanos , Linfócitos T , Leucócitos Mononucleares , Camundongos SCID , Anticorpos Biespecíficos/genética , Anticorpos Biespecíficos/uso terapêutico , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Antineoplásicos/metabolismo
4.
Stem Cells Transl Med ; 12(1): 39-53, 2023 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-36610716

RESUMO

Current mesenchymal stem cell (MSC) research is based on xenotransplantation of human MSCs (hMSCs) in immunodeficient mice and cannot comprehensively predict MSC repair mechanisms and immunomodulatory effects in damaged tissue. This study compared the therapeutic efficacy, mechanisms, and immune response of hMSCs and mouse MSCs (mMSCs) in immunocompetent mice with CCl4-induced acute liver failure. mMSCs maintained F4/80+ hepatic macrophage recruitment into the damaged liver region, increased IL-6-dependent hepatocyte proliferation, and reduced inflammatory TNF-α cytokine secretion. Moreover, mMSCs reduced α-SMA+ myofibroblast activation by lowering TGF-ß1 accumulation in damaged liver tissue. In contrast, hMSCs lowered TNF-α and TGF-ß1 by reducing the recruitment of F4/80+ hepatic macrophages, which lost the ability to remove debris and induce IL-6 liver regeneration. Finally, hMSCs, but not mMSCs, caused a significant antibody response in immunocompetent mice; therefore, hMSCs are unsuitable for long-term MSC studies. This comparative study provides reference information for further MSC studies of immunocompetent mice.


Assuntos
Falência Hepática Aguda , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Animais , Humanos , Camundongos , Imunidade , Interleucina-6/farmacologia , Falência Hepática Aguda/terapia , Fator de Crescimento Transformador beta1/farmacologia , Fator de Necrose Tumoral alfa/farmacologia
5.
J Adv Res ; 46: 159-171, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35752438

RESUMO

INTRODUCTION: The tumor microenvironment is mainly flooded with immunosuppressive cells and inhibitory cytokines, resulting in the inability of effective immune cells to infiltrate and recognize tumors and even the loss of anti-cancer ability. OBJECTIVES: We propose a novel HDAC6/HSP90 dual inhibitory strategy as well as a chemoimmunotherapeutic agent that does not only kill tumor cells but also destroys the tumor microenvironment and enhances anti-cancer immunity. METHODS: A hybrid scaffold construction approach was leveraged to furnish a series of rationally designed resorcinol-based hydroxamates as dual selective HDAC6/HSP90 inhibitors. The drug design campaign commenced with a fragment recruitment process to pinpoint validated structural units to inhibit HDAC6 and HSP90, followed by their installation in flexible HDAC inhibitory templates via an efficient and facile multistep synthetic route. Subsequent evaluations identified a strikingly potent selective HDAC6/HSP90 dual inhibitor (compound 17) via molecular and biological analysis in vitro and in vivo. RESULTS: Compound 17 exhibited not only direct cytotoxicity to cancer cells but also downregulated immune checkpoints (PD-L1 and IDO) expression in tumors via the inhibition of STAT1 pathway and degradation of oncogene proteins (Src, AKT, Rb, and FAK), leading to in vivo tumor growth inhibition. These multiple effects enabled the effector T cells to largely infiltrate into the tumor region and release granzyme B to kill cancer cells. In addition, compound 17 also decreased TGF-ß secretion from normal cells, resulting in the systemic reduction of immunosuppressive regulatory T cells. Delightfully, a cocktail treatment of compound 17 and anti-PD-1 antibodies demonstrated synergistic efficacy to eliminate solid tumors with 83.9% of tumor growth inhibition. CONCLUSION: In summary, the impressive activity profile of compound 17, as an effective anticancer agent and a potential immunosensitizer, forecasts the application of HDAC6/HSP90 dual inhibitory strategy to overcome the immunosuppressive tumor microenvironment.


Assuntos
Antineoplásicos , Microambiente Tumoral , Desacetilase 6 de Histona/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/química , Proteínas de Choque Térmico HSP90/metabolismo
6.
Orthop J Sports Med ; 10(8): 23259671221115423, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35990875

RESUMO

Background: There is a lack of consensus regarding the optimal technique for revision posterior cruciate ligament (PCL) reconstruction. Purpose: To evaluate midterm outcomes after revision PCL reconstruction using a single-bundle transtibial autograft. Study Design: Case series; Level of evidence, 4. Methods: We reviewed 17 patients who underwent revision PCL reconstruction performed in our medical center by a single surgeon from 2003 to 2016. The cohort included 12 male and 5 female patients with a mean age of 31.3 years (range, 17-48 years). All of the patients underwent single-bundle transtibial reconstruction using the same surgical technique and were reviewed at a minimum of 4 years postoperatively. Preoperative and postoperative posterior stress radiography was performed. The preoperative tibial slope and tibiofemoral angle were also measured. Preoperative and postoperative functional outcomes were evaluated using the International Knee Documentation Committee (IKDC) subjective and objective scores as well as the Lysholm score. Results: The most common factor that contributed to the failure of primary surgery was misplaced tunnels, especially on the femoral side. There were 2 patients who had grade 2 laxity preoperatively, and 15 patients had grade 3 laxity preoperatively. At the latest follow-up, all 17 patients had grade 1 laxity. On posterior stress radiography, posterior displacement improved from 10.8 ± 2.1 mm preoperatively to 2.9 ± 1.1 mm at the latest follow-up (P < .001). The IKDC subjective score improved from 34.9 ± 6.8 preoperatively to 75.3 ± 15.7 postoperatively (P < .001), and the Lysholm score improved from 38.1 ± 10.0 preoperatively to 88.5 ± 7.6 postoperatively (P < .001). All patients reached the minimal clinically important difference (MCID) for the Lysholm score, and 94% reached the MCID for the IKDC subjective score, with 65% reaching the Patient Acceptable Symptom State. Conclusion: According to the findings of this study, arthroscopic revision PCL reconstruction with a single-bundle transtibial autograft offered satisfactory outcomes at midterm follow-up.

7.
J Control Release ; 344: 235-248, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35288168

RESUMO

Immunotherapy is blooming in recent years. However, this therapy needs to overcome off-target effects, cytokine release syndrome, and low responses in the 'cold' tumor environment. Herein, various combinations of immunotherapies and chemotherapies were proposed to transform 'cold' tumors into 'hot' tumors to enhance the efficacy of immunotherapies. In this study, we prepared a biocompatible ganetespib (GSP)-loaded PEGylated nanocarriers (NCs) with a thin-film method, which exhibited a small particle size (~220.6 nm), high drug loading (~5.8%), and good stability. We designed and produced the cluster of differentiation 3 (CD3)/programmed death ligand 1 (PD-L1)/methoxy-polyethylene glycol (mPEG) trispecific antibodies (TsAbs) as bispecific T-cell engagers (BiTEs) to non-covalently bind the GSP-NCs via anti-mPEG fragment and endowed the GSP-NCs with a targeting ability and immunotherapeutic potential to activate cytotoxic T cells. Decoration of the GSP-NCs with TsAbs (BiTEs-GSP-NCs) significantly promoted the cellular uptake and showed synergistic effects through respective anti-PD-L1 and anti-CD3 activation of T cell-mediated cytotoxicity. In vivo tumor-inhibition studies also showed that the BiTEs-GSP-NCs could inhibit tumor growth with the GSP chemodrug and increase T-cell infiltration. This study provides a promising drug delivery strategy for cancer immunochemotherapy.


Assuntos
Anticorpos Biespecíficos , Neoplasias , Anticorpos Biespecíficos/uso terapêutico , Sistemas de Liberação de Medicamentos , Humanos , Imunoterapia/métodos , Neoplasias/tratamento farmacológico , Preparações Farmacêuticas , Polietilenoglicóis
8.
Biomater Sci ; 10(1): 202-215, 2021 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-34826322

RESUMO

The therapeutic efficacy of methoxypolyethylene glycol (mPEG)-coated nanomedicines in solid tumor treatment is hindered by tumor-associated fibroblasts (TAFs), which promote tumor progression and form physical barriers. We developed an anti-HER2/anti-FAP/anti-mPEG tri-specific antibody (TsAb) for one-step conversion of mPEG-coated liposomal doxorubicin (Lipo-Dox) to immunoliposomes, which simultaneously target HER2+ breast cancer cells and FAP+ TAFs. The non-covalent modification did not adversely alter the physical characteristics and stability of Lipo-Dox. The TsAb-Lipo-Dox exhibited specific targeting and enhanced cytotoxicity against mono- and co-cultured HER2+ breast cancer cells and FAP+ TAFs, compared to bi-specific antibody (BsAb) modified or unmodified Lipo-Dox. An in vivo model of human breast tumor containing TAFs also revealed the improved tumor accumulation and therapeutic efficacy of TsAb-modified mPEGylated liposomes without signs of toxicity. Our data indicate that arming clinical mPEGylated nanomedicines with the TsAb is a feasible and applicable approach for overcoming the difficulties caused by TAFs in solid tumor treatment.


Assuntos
Anticorpos Biespecíficos , Neoplasias da Mama , Fibroblastos Associados a Câncer , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Doxorrubicina , Feminino , Humanos , Lipossomos , Nanomedicina , Polietilenoglicóis
9.
Biomaterials ; 278: 121166, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34634663

RESUMO

In this study, PEGylated poly (lactide-co-glycolide) (PLGA) thermosensitive composite hydrogels (DTgels) loaded with bispecific anti-cluster of differentiation 3 (CD3) scFv T-cell/anti-epidermal growth factor receptor (EGFR) Fab engager (BiTEE) were subcutaneously (s.c.) injected for the in situ formation of a drug deposit to resolve limitations of the clinical application of the BiTEE of a short half-life and potential side effects. Three kinds of DTgels prepared with different ratios of methoxy poly (ethylene glycol) (mPEG)-PLGA (diblock copolymer, DP) and PLGA-PEG-PLGA (triblock copolymer, TP) were designated DTgel-1, DTgel-2, and DTgel-2S. All three DTgel formulations showed thermosensitive properties with a sol-gel transition temperature at 28-34 °C, which is suitable for an injection. An in vitro release study showed that all DTgel formulations loaded with stabilized BiTEE extended the release of the BiTEE for up to 7 days. In an animal pharmacokinetics study, an s.c. injection of BiTEE/DTgel-1, BiTEE/DTgel-2, or BiTEE/DTgel-2S respectively prolonged the half-life of the BiTEE by 3.5-, 2.0-, and 2.2-fold compared to an intravenous injection of the BiTEE solution. Simultaneously, BiTEE/DTgel formulations showed almost no proinflammatory cytokine release in mice injected with T cells after s.c. administration. Results of an animal antitumor (MDA-MB-231) study indicated that an s.c. injection of the BiTEE/DTgel formulations significantly improved the antitumor efficacy compared to an intravenous (i.v.) or s.c. injection of the BiTEE solution. Moreover, BiTEE/DTgel formulations led to enhanced T-cell recruitment to solid-tumor sites. In conclusion, the in situ formation of injectable PEGylated PLGA thermosensitive hydrogels loaded with the BiTEE was successfully carried out to increase its half-life, maintain a constant blood level within therapeutic windows, and enhance T-cell recruitment to solid-tumor sites resulting in exceptional treatment efficacy.


Assuntos
Portadores de Fármacos , Polietilenoglicóis , Animais , Diferenciação Celular , Hidrogéis , Camundongos , Poliésteres , Temperatura
10.
Mol Ther Nucleic Acids ; 17: 477-490, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31336235

RESUMO

Paclitaxel (PTX) is a widely used chemotherapy drug; however, frequent use causes multidrug resistance (MDR), which limits the utility of PTX against advanced non-small-cell lung cancer (NSCLC). PTX-resistant subline (NCI-H23-TXR) was established in vitro by exposing NCI-H23 cells to gradually increased concentrations of PTX in culture medium. Distinct Beclin expression of autophagy level was observed between resistant NCI-H23-TXR and parental NCI-H23 cells. Beclin-small interfering RNA (siRNA) was selected to restore sensitivity of PTX against NCI-H23-TXR. Chondroitin sulfate-polyethylenimine (CS-PEI) was constructed for delivery and protection of Beclin-siRNA. To delineate the underlying molecular mechanism of Beclin knockdown, we analyzed different MDR expression proteins of two cells using western blot, and the corresponding genes were confirmed by real-time PCR. Compared with NCI-H23, NCI-H23-TXR had higher expression levels in P-glycoprotein (P-gp) and multidrug resistance protein 7 (ABCC10). Knockdown of Beclin simultaneously inhibited P-gp and ABCC10, and renewed the sensitivity of PTX against NCI-H23-TXR. Research on zebrafish embryos revealed that tumor sizes decreased in NCI-H23 tumor xenografts but remained intact in NCI-H23-TXR tumor xenografts as zebrafish were treated with 1 µg/mL PTX. In contrast, the tumor sizes decreased in NCI-H23-TXR tumor xenografts with zebrafish pre-transfected with CS-PEI/Beclin-siRNA followed by the same treatment of PTX. The role of autophagy was associated with MDR development. This study paves the way for a new avenue of PTX in MDR-related lung cancer therapy using CS-PEI as a gene delivery carrier.

11.
Anal Chem ; 91(13): 8310-8317, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31144495

RESUMO

An insufficient amount of detection antibodies bound to their antigens usually limits the sensitivity of immunoassays. Here, we describe a simple method to improve the detection limit and sensitivity of various immunoassays by mixing detection antibodies with a soluble poly protein G (named 8pG). 8pG was developed by fusing eight repeated fragment crystallizable (Fc) binding domains of streptococcal protein G to a linear polymer. Simply mixing detection antibodies with 8pG to form an antibody/8pG complex largely increased the accumulation of detection antibody to target molecules, which dramatically enhanced the sensitivity in direct ELISA, sandwich ELISA, Western blot, and flow cytometry systems, separately. The detection limit of Western blot for low-abundance PEGylated interferon (Pegasys) and recombinant human CTLA4 (rhCTLA4) improved by at least 13-fold and 31-fold, respectively, upon mixing detection antibodies with 8pG. Moreover, the nanoscale size of the antibody/8pG complex did not influence the granularity and dimension of target cells in the flow cytometry system. Collectively, we provide a quick and easy-to-operate method to make various immunoassays to sensitively detect low-abundance target molecules by just mixing their detection antibodies with 8pG.


Assuntos
Imunoensaio/normas , Anticorpos/química , Proteínas de Bactérias/química , Humanos , Imunoensaio/métodos , Limite de Detecção , Polímeros/química , Sensibilidade e Especificidade
12.
Sci Rep ; 8(1): 17868, 2018 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-30552393

RESUMO

The sensitivity of traditional enzyme-linked immunosorbent assays (ELISAs) is limited by the low binding avidity and heterogeneous orientation of capture antibodies coated on polystyrene-based microplates. Here, we developed a highly sensitive ELISA strategy by fixing poly-protein G-expressing cells on microplates to improve the coating amount and displayed orientation of capture antibodies. One or eight repeated fragment crystallisable (Fc) binding domains of protein G are stably expressed on the surface of BALB/c 3T3 cells (termed 1pG cells or 8pG cells), which then act as highly antibody-trapping microparticles. The 8pG cells showed higher antibody-trapping ability than the 1pG cells did. The antibody-coating amount of the 8pG cell-based microplates was 1.5-23 times and 1.2-6.8 times higher than that of traditional polystyrene-based and commercial protein G-based microplates, respectively. The 8pG cell-based microplates were then applied to an anti-IFN-α sandwich ELISA and an anti-CTLA4 competitive ELISA, respectively, and dramatically enhanced their detection sensitivity. Importantly, direct coating unpurified capture antibody produced by mammalian cells did not impair the antigen-capturing function of 8pG cell-based microplates. The 8pG cell-based microplates exhibited a significant improvement in antibody-coating amount and preserved the homogeneous orientation of capture antibodies, making them a potential replacement for traditional microplates in various formats of ELISAs.


Assuntos
Anticorpos/metabolismo , Proteínas de Bactérias/metabolismo , Ensaio de Imunoadsorção Enzimática/métodos , Proteínas Recombinantes/metabolismo , Animais , Células 3T3 BALB , Proteínas de Bactérias/genética , Células Imobilizadas , Camundongos , Ligação Proteica , Proteínas Recombinantes/genética , Sensibilidade e Especificidade
13.
Sci Rep ; 8(1): 4256, 2018 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-29511251

RESUMO

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

14.
Sci Rep ; 7(1): 3142, 2017 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-28600512

RESUMO

Intestinal bacterial ß-glucuronidase (ßG) hydrolyzes glucuronidated metabolites to their toxic form in intestines, resulting in intestinal damage. The development of a method to inhibit ßG is thus important but has been limited by the difficulty of directly assessing enzyme activity in live animals. Here, we utilized a fluorescent probe, fluorescein di-ß-D-glucuronide (FDGlcU), to non-invasively image the intestinal bacterial ßG activity in nude mice. In vitro cell-based assays showed that the detection limit is 104 colony-forming units/well of ßG-expressing bacteria, and that 7.81 ng/mL of FDGlcU is enough to generate significant fluorescent signal. In whole-body optical images of nude mice, the maximum fluorescence signal for ßG activity in intestines was detected 3 hours after gavage with FDGlcU. Following pretreatment with a bacterial ßG inhibitor, the fluorescence signal was significantly reduced in abdomens and excised intestines images. For a 4-day antibiotic treatment to deplete intestinal bacteria, the FDGlcU-based images showed that the ßG activity was decreased by 8.5-fold on day 4 and then gradually increased after treatment stopped. The results suggested that FDGlcU-based imaging revealed the in vitro and in vivo activity of intestinal bacterial ßG, which would facilitate pharmacodynamic studies of specific bacterial ßG inhibitors in animal studies.


Assuntos
Bactérias/enzimologia , Fluoresceínas/química , Corantes Fluorescentes/química , Glucuronidase/metabolismo , Intestinos/microbiologia , Imagem com Lapso de Tempo/métodos , Animais , Antibacterianos/administração & dosagem , Antibacterianos/farmacocinética , Bactérias/efeitos dos fármacos , Proteínas de Bactérias/metabolismo , Fluoresceínas/administração & dosagem , Corantes Fluorescentes/administração & dosagem , Hidrólise , Intestinos/efeitos dos fármacos , Limite de Detecção , Camundongos , Camundongos Nus , Imagem Molecular
15.
Sci Rep ; 7(1): 989, 2017 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-28428542

RESUMO

The sensitivities of solid-phase immunoassays are limited by the quantity of detection antibodies bound to their antigens on the solid phase. Here, we developed a poly-protein G-expressing bacterium as an antibody-trapping microparticle to enhance the signals of immunoassays by increasing the accumulation of detection antibodies on the given antigen. Eight tandemly repeated fragment crystallisable (Fc) binding domains of protein G were stably expressed on the surface of Escherichia coli BL21 cells (termed BL21/8G). BL21/8G cells showed a higher avidity for trapping antibodies on their surface than monomeric protein G-expressing BL21 (BL21/1G) cells did. In the sandwich enzyme-linked immunosorbent assay (ELISA), simply mixing the detection antibody with BL21/8G provided a detection limit of 6 pg/mL for human interferon-α (IFN-α) and a limit of 30 pg/mL for polyethylene glycol (PEG)-conjugated IFN-α (Pegasys), which are better than that of the traditional ELISA (30 pg/mL for IFN-α and 100 pg/mL for Pegasys). Moreover, the sensitivity of the Western blot for low-abundance Pegasys (0.4 ng/well) was increased by 25 folds upon mixing of an anti-PEG antibody with BL21/8G cells. By simply being mixed with a detection antibody, the poly-protein G-expressing bacteria can provide a new method to sensitively detect low-abundance target molecules in solid-phase immunoassays.


Assuntos
Anticorpos Monoclonais/metabolismo , Antígenos de Bactérias/genética , Escherichia coli/crescimento & desenvolvimento , Antígenos de Bactérias/química , Antígenos de Bactérias/imunologia , Sítios de Ligação , Elementos Facilitadores Genéticos , Ensaio de Imunoadsorção Enzimática , Escherichia coli/genética , Escherichia coli/metabolismo , Humanos , Interferon gama/imunologia , Limite de Detecção
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