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G protein-coupled estrogen receptor 1 (GPER-1) plays important roles in estrogen-mediated neuroprotection. However, protective effects of GPER-1 on blood-brain barrier (BBB) after ischemic stroke have not been determined. The aim of present study was to determine whether GPER-1 activation ameliorates BBB permeability in ovariectomized rats with induced global cerebral ischemia (GCI). GCI was induced by 4-vessel occlusion for 20 min followed by 24 h reperfusion period. The GPER-1 agonist (G1) was bilaterally administered immediately upon reperfusion by intracerebroventricular (icv) injection. We found that the GPER-1 agonist could significantly decrease immunoglobulin G (IgG) extravasation and increase the levels of tight junctions (occludin and claudin-5) in the CA1 at 24 h of reperfusion after GCI. Further, protein levels of vascular endothelial growth factor A (VEGF-A) was significantly decreased in the ischemic CA1 by G1. Our results suggest that GPER-1 activation reduce tight junctions disruption via inhibition of VEGF-A expression after ischemic injury. [ABSTRACT FROM AUTHOR]

In recent years a variety of recombinant methods have been developed for efficient production of bispecific antibodies (BsAb) in various formats. Bispecific diabody (bDAb), a 55–60 kDa molecule comprising two non-covalently associated cross-over single chain Fv (scFv) polypeptides, represents one of the most promising as well the most straightforward approaches to BsAb production. Here we constructed a bDAb, using two human scFv, 11F8 and A12, directed against the epidermal growth factor receptor (EGFR) and the insulin-like growth factor receptor (IGFR), respectively, as the building blocks. A total of 8 scFv and diabody constructs were prepared comprising the same two variable heavy (VH) and variable light (VL) chain domains but arranged in different orientations. VH/VL orientation, i.e., VH–linker–VL or VL–linker–VH, showed significant effects on the expression and antigen-binding activity of scFv and monospecific diabody of both 11F8 and A12. Further, only 2 out of the 4 possible VH/VL orientations/arrangements in bDAb construction yielded active products that retain binding activity to both EGFR and IGFR. Both active bDAb preparations retained their original antigen-binding activity after incubation at 37 °C in mouse serum for up to 7 days, indicating excellent stability of the constructs. Taken together, our results underscore the importance of identifying/selecting optimal VH/VL orientation/arrangement for efficient production of active bDAb. [Copyright &y& Elsevier]

Abstract: Epitope-based vaccines designed to induce cellular immune response and antibody responses specific for infectious bronchitis virus (IBV) are being developed as a means for increasing vaccine potency. In this study, we selected seven epitopes from the spike (S1), spike (S2), and nucleocapsid (N) protein and constructed a multi-epitope DNA vaccine. The 7-day-old chickens were immunized intramuscularly with multi-epitope DNA vaccine encapsulated by liposome and boosted two weeks later, and were challenged by virulent IBV strain five weeks post booster. The results showed that multi-epitope DNA vaccine led to a dramatic augmentation of humoral and cellular responses, and provided up to 80.0% rate of immune protection. The novel immunogenic chimeric multi-epitope DNA vaccine revealed in this study provided a new candidate target for IBV vaccine development. [Copyright &y& Elsevier]

Thyroid stimulating hormone deficiency is the cornerstone of treatment for metastatic thyroid cancer. Due to the loss of follicular epithelial cells in thyroid cancer, the thyroid gland degenerates to 85% of its original size. When thyroid stimulating hormone is restored, follicular epithelial cells in thyroid cancer regenerate, which is postulated to be related to stem-like cells. By single cell RNA seq, we found a group of rare thyroid follicular epithelial cells in mouse metastatic thyroid cancer, which expressed stem-like genes (CD44V6+ and CD133+) and a large number of differentiated cells (CD44V6+ and CD24+). In mouse and in organoids, the two subsets contribute equally to metastatic thyroid cancer regeneration. The analysis of human metastatic thyroid cancer revealed that the differentiated thyroid follicular epithelial cell subpopulation was similar to that of the stem like epithelial cell subpopulation, and the regeneration potential was also enhanced after thyroid stimulating hormone ablation. Accordingly, we propose that the regeneration of metastatic thyroid cancer is driven by almost all persistent thyroid follicular epithelial cells, not only by few stem-like cells. • We found rare stem cells (CD133+) and a large number of differentiated cells (CD24+) in metastatic thyroid cancer of mice. • In mouse and in organoids, the two subsets contribute equally to metastatic thyroid cancer regeneration. • The regeneration of metastatic thyroid cancer is driven by almost all follicular epithelial cells, not just few stem cells. [ABSTRACT FROM AUTHOR]

Long noncoding RNAs (lncRNAs) have been implicated in a range of developmental processes and diseases, but the roles and mechanisms by which they act in adipogenic differentiation and adipose tissue biology are still unknown. By comparing the different expression patterns of lncRNAs before and after the adipocyte differentiation of human adipose-derived mesenchymal stem cells (hADSCs), we characterized a novel lncRNA, AC092834.1, which is significantly increased in preadipocytes. By gain- and loss-of-function experiments, we demonstrated that lncRNA AC092834.1 potentiated adipogenic differentiation through directly increasing the level of expression of DKK1, which competitively binds with LRP5 to inhibit the Wnt-β-catenin pathway and reduce the inhibition of adipogenesis by Wnt signaling. This finding provides novel mechanistic insights into a critical role for lncRNA AC092834.1 as a regulator of adipogenic differentiation, which expands our knowledge about the molecular mechanisms of obesity and other adipogenic differentiation-related disorders. • The novel lncRNA, AC092834.1, is upregulated in hADSCs adipogenesis. • LncRNA AC092834.1 could positive regulate adipogenic differentiation of hADSCs. • LncRNA AC092834.1 induce DKK1 expression and antagonize Wnt/β-catenin pathway. [ABSTRACT FROM AUTHOR]

Abstract: Compelling evidence suggest that vascular endothelial growth factor (VEGF) and its receptors, especially receptor 2 (VEGFR2, or kinase insert domain-containing receptor, KDR), play a critical role in angiogenesis under both physiological and pathological conditions, including cancer and angiogenic retinopathies such as age-related macular degeneration (AMD). To this end, inhibition of angiogenesis with antagonists to either VEGF or KDR has yielded significant therapeutic efficacy both in preclinical studies in animal models and in clinical trials in patients with cancer and AMD. We previously reported the identification of a high affinity, fully human anti-KDR antibody fragment, 1121B Fab, through a highly stringent affinity maturation process with a Fab originally isolated from a naïve human antibody phage display library. In this study, we demonstrate that 1121B Fab is able to strongly block KDR/VEGF interaction, resulting in potent inhibition of an array of biological activities of VEGF, including activation of the receptor and its signaling pathway, intracellular calcium mobilization, and migration and proliferation of endothelial cells. Taken together, our data lend strong support to the further development of 1121B Fab fragment as an anti-angiogenesis agent in both cancer and angiogenic retinopathies. [Copyright &y& Elsevier]