Effect of Human Amniotic Epithelial Stem Cell Transplantation on Preterm Premature Rupture of Fetal Membrane Using the Amniotic Pore Culture Technique in vitro.

OBJECTIVES: The objective of this study was to evaluate the efficacy of cell therapy using human amniotic epithelial stem cells (hAESCs) for the treatment of premature rupture of membranes (PROM) in vitro. DESIGN: Using the amniotic pore culture technique (APCT), we mimicked the environment of PROM in vitro, thus enabling the observation of the healing process of hAESC-treated amniotic membranes. MATERIALS: Amniotic membrane samples were collected from placentas of pregnant women who underwent elective cesarean sections. APCT model and isolated hAESCs were used in this study. All patients who participated in this study provided their written informed consent prior to the commencement of the study. SETTINGS: To create the APCT model in vitro, isolated amniotic membranes were punched to create 5 mm diameter circles and re-punched to form a 1-mm pore at the center. Membranes were cultured in α-minimal essential medium, and the hAESCs were collected and cultured as well. Subsequently, the APCT models were divided into two groups: hAESC treated and control. METHODS: Within the culture period, pore sizes were calculated to evaluate the degree of tissue regeneration in both groups. We then evaluated the histology, cell density, and epithelial thickness of the regenerated tissues. Statistical analyses were performed using SPSS software ver. 20.0 (IBM, Armonk, NY, USA) with repeated-measures one-way analysis of variance or paired samples t test. The significance level was set at p < 0.05. RESULTS: As per the evaluation of the APCT model in vitro, the pore size in the hAESC-treated group reduced by 62.2% on day 6 (62.2 ± 0.19, n = 24), whereas in the control group, it shrank by only 36.8% (p < 0.05) (36.8 ± 0.19, n = 24). Furthermore, the epithelial thickness in the amniotic epithelial stem cell-treated group (10.08 ± 1.26 µm, n = 8) was significantly higher than that in the control group (5.87 ± 0.94 µm, n = 8). Cell density in the regenerated tissue in the amniotic epithelial stem cell-treated group (57 ± 2.77, n = 8) was significantly higher than that in the control group (49 ± 2.23, n = 8). LIMITATIONS: In this study, we did not explore the molecular mechanisms by which hAESCs participate in membrane healing in the APCT model. Although our results showed a significant difference, this difference was not too obvious. Therefore, further research on the mechanisms of hAESCs is needed, with more amniotic tissues and APCT samples being tested. CONCLUSIONS: We developed an APCT model to investigate the PROM conditions in vitro. By implanting donor hAESCs in the pores of the APCT model, we observed that hAESCs seeding accelerated pore healing in vitro. Thus, hAESCs may be a valuable source of cells for cell therapies in regenerative medicine.

Nose-to-brain delivery of hyaluronate - FG loop peptide conjugate for non-invasive hypoxic-ischemic encephalopathy therapy.

The intranasal drug administration has attracted great interest as a non-invasive route allowing targeted delivery of drugs directly to the brain. However, one of the main issues in nasal drug administration is mucociliary clearance. Hyaluronate (HA) has been widely used as a mucoadhesive excipient for ocular, rectal, and vaginal delivery. Here, FG loop peptide (FGL) was conjugated to HA for improving enzymatic stability and delivery efficiency from the nose to the brain. The successful conjugation of FGL to aldehyde modified HA was confirmed by gel permeation chromatography (GPC) and 1H nuclear magnetic resonance (NMR). The outstanding enzymatic stability of HA-FGL conjugate was also corroborated by the GPC. The HA-FGL conjugate showed enhanced binding affinity onto nasal epithelial cells. In addition, in vivo nose-to-brain delivery of HA-FGL conjugate could be visualized by using an IVIS imaging system and fluorescence microscopy. Finally, in vivo therapeutic effect of HA-FGL conjugate was successfully confirmed by histological analysis, transferase-mediated uridine 5-triphosphate-biotin nick end-labeling (TUNEL) assay, immunofluorescent staining, transmission electron microscopy (TEM), and rotarod tests in hypoxic-ischemic encephalopathy model animals.

Bioimaging of botulinum toxin and hyaluronate hydrogels using zwitterionic near-infrared fluorophores.

BACKGROUND: The injection of botulinum toxin (BTX) to reduce facial wrinkles is one of the most frequently performed plastic surgery procedures. The biocompatible hydrogels are injected with BTX for effective tissue augmentation. However, it is difficult to determine the interval of injection for effective tissue augmentation. METHOD: BTX and hyaluronate (HA) hydrogels were labeled with zwitterionic (ZW) near-infrared (NIR) fluorophores and visualized for 3 weeks after injection to BALB/c nude mice. RESULTS: BTX-ZW conjugates and diaminohexane (DAH)-HA-ZW hydrogels were successfully prepared by the conventional EDC/NHS chemistry. Using the NIR fluorescence imaging, we confirmed that approximately 10% of BTX-ZW conjugates and 50% of DAH-HA-ZW hydrogels remained 3 weeks post-injection. CONCLUSION: This bioimaging technique using invisible NIR fluorescence light can be exploited for various biomedical applications.

Targeted systemic mesenchymal stem cell delivery using hyaluronate - wheat germ agglutinin conjugate.

A variety of receptors for hyaluronate (HA), a natural linear polysaccharide, were found in the body, which have been exploited as target sites for HA-based drug delivery systems. In this work, mesenchymal stem cells (MSCs) were surface-modified with HA - wheat germ agglutinin (WGA) conjugate for targeted systemic delivery of MSCs to the liver. WGA was conjugated to HA by coupling reaction between aldehyde-modified HA and amine group of WGA. The conjugation of WGA to HA was corroborated by gel permeation chromatography (GPC) and the successful surface modification of MSCs with HA-WGA conjugate was confirmed by confocal microscopy. The synthesized HA-WGA conjugate could be incorporated onto the cellular membrane by agglutinating the cell-associated carbohydrates. Fluorescent imaging for in vivo biodistribution visualized the targeted delivery of the HA-WGA/MSC complex to the liver after intravenous injection. This new strategy for targeted delivery of MSCs using HA-WGA conjugate might be successfully exploited for various regenerative medicines including cell therapy.

Hyaluronate-gold nanoparticle/tocilizumab complex for the treatment of rheumatoid arthritis.

Rheumatoid arthritis (RA) is a chronic inflammatory immune disease causing the inflammation of synovial membrane and the articular cartilage destruction. In this work, hyaluronate-gold nanoparticle/Tocilizumab (HA-AuNP/TCZ) complex was prepared for the treatment of RA. AuNP was used as a drug carrier with antiangiogenic effect. TCZ is a humanized monoclonal antibody against the interleukin-6 (IL-6) receptor and used as an immunosuppressive drug by interfering IL-6 in the pathogenesis of RA. HA is known to have cartilage-protective and lubricant effects. HA was modified with cystamine via reductive amination, which was reduced with dithiothreitol (DTT) to prepare end-group thiolated HA (HA-SH). AuNP was chemically modified with HA-SH and physically modified with TCZ. The formation of HA-AuNP/TCZ complex was corroborated by UV-vis spectroscopy, dynamic light scattering (DLS), and transmission electron microscopy (TEM). The therapeutic effect of HA-AuNP/TCZ complex on RA was confirmed in collagen-induced arthritis (CIA) model mice by ELISA, histological, and Western blot analyses.

Repression of TNF-alpha-induced IL-8 expression by the glucocorticoid receptor-beta involves inhibition of histone H4 acetylation.

Increased expression of a number of proinflammatory genes, including IL-8, is associated with inflammatory conditions such as asthma. Glucocorticoid receptor (GR)beta, one of the GR isoforms, has been suggested to be upregulated in asthma associated with glucocorticoid insensitivity and to work as a dominant negative inhibitor of wild type GRalpha. However, recent data suggest that GRbeta is not a dominant negative inhibitor of GRalpha in the transrepressive process and has its own functional role. We investigated the functional role of GRbeta expression in the suppressive effect of glucocorticoids on tumor necrosis factor (TNF)-alpha-induced IL-8 release in an airway epithelial cell line. GRbeta expression was induced by treatment of epithelial cells with either dexamethasone or TNF-alpha. GRbeta was able to inhibit glucocorticoid-induced transcriptional activation mediated by binding to glucocorticoid response elements (GREs). The suppressive effect of dexamethasone on TNF-alpha-induced IL-8 transcription was not affected by GRbeta overexpression, rather GRbeta had its own weak suppressive activity on TNF-alpha-induced IL-8 expression. Overall histone deacetylase activity and histone acetyltransferase activity were not changed by GRbeta overexpression, but TNF-alpha-induced histone H4 acetylation at the IL-8 promoter was decreased with GRbeta overexpression. This study suggests that GRbeta overexpression does not affect glucocorticoid-induced suppression of IL-8 expression in airway epithelial cells and GRbeta induces its own histone deacetylase activity around IL-8 promoter site.