Real-Time Imaging of Rabbit Retina with Retinal Degeneration by Using Spectral-Domain Optical Coherence Tomography

Background: Recently, a transgenic rabbit with rhodopsin Pro 347 Leu mutation was generated as a model of retinitis pigmentosa (RP), which is characterized by a gradual loss of vision due to photoreceptor degeneration. The purpose of the current study is to noninvasively visualize and assess time-dependent changes in the retinal structures of a rabbit model of retinal degeneration by using speckle noise-reduced spectral-domain optical coherence tomography (SD-OCT). Methodology/Principal Findings: Wild type (WT) and RP rabbits (aged 4–20 weeks) were investigated using SD-OCT. The total retinal thickness in RP rabbits decreased with age. The thickness of the outer nuclear layer (ONL) and between the external limiting membrane and Bruch’s membrane (ELM–BM) were reduced in RP rabbits around the visual streak, compared to WT rabbits even at 4 weeks of age, and the differences increased with age. However, inner nuclear layer (INL) thickness in RP rabbits did not differ from that of WT during the observation period. The ganglion cell complex (GCC) thickness in RP rabbits increased near the optic nerve head but not around the visual streak in the later stages of the observation period. Hyper-reflective change was widely observed in the inner segments (IS) and outer segments (OS) of the photoreceptors in the OCT images of RP rabbits. Ultrastructural findings in RP retinas included the appearance of small rhodopsin-containing vesicles scattered in the extracellular space around the photoreceptors

COX-2-mediated stimulation of the lymphangiogenic factor VEGF-C in human breast cancer

Increased expression of COX-2 or VEGF-C has been correlated with progressive disease in certain cancers. Present study utilized several human breast cancer cell lines (MCF-7, T-47D, Hs578T and MDA-MB-231, varying in COX-2 expression) as well as 10 human breast cancer specimens to examine the roles of COX-2 and prostaglandin E (EP) receptors in VEGF-C expression or secretion, and the relationship of COX-2 or VEGF-C expression to lymphangiogenesis. We found a strong correlation between COX-2 mRNA expression and VEGF-C expression or secretion levels in breast cancer cell lines and VEGF-C expression in breast cancer tissues. Expression of LYVE-1, a selective marker for lymphatic endothelium, was also positively correlated with COX-2 or VEGF-C expression in breast cancer tissues. Inhibition of VEGF-C expression and secretion in the presence of COX-1/2 or COX-2 inhibitors or following downregulation of COX-2 with COX-2 siRNA established a stimulatory role COX-2 in VEGF-C synthesis by breast cancer cells. EP1 as well as EP4 receptor antagonists inhibited VEGF-C production indicating the roles of EP1 and EP4 in VEGF-C upregulation by endogenous PGE2. Finally, VEGF-C secretion by MDA-MB-231 cells was inhibited in the presence of kinase inhibitors for Her-2/neu, Src and p38 MAPK, indicating a requirement of these kinases for VEGF-C synthesis. These results, for the first time, demonstrate a regulatory role of COX-2 in VEGF-C synthesis (and thereby lymphangiogenesis) in human breast cancer, which is mediated at least in part by EP1/EP4 receptors

Bezlotoxumab for Prevention of Recurrent Clostridium difficile Infection

BACKGROUND Clostridium difficile is the most common cause of infectious diarrhea in hospitalized patients. Recurrences are common after antibiotic therapy. Actoxumab and bezlotoxumab are human monoclonal antibodies against C. difficile toxins A and B, respectively. METHODS We conducted two double-blind, randomized, placebo-controlled, phase 3 trials, MODIFY I and MODIFY II, involving 2655 adults receiving oral standard-of-care antibiotics for primary or recurrent C. difficile infection. Participants received an infusion of bezlotoxumab (10 mg per kilogram of body weight), actoxumab plus bezlotoxumab (10 mg per kilogram each), or placebo; actoxumab alone (10 mg per kilogram) was given in MODIFY I but discontinued after a planned interim analysis. The primary end point was recurrent infection (new episode after initial clinical cure) within 12 weeks after infusion in the modified intention-to-treat population. RESULTS In both trials, the rate of recurrent C. difficile infection was significantly lower with bezlotoxumab alone than with placebo (MODIFY I: 17% [67 of 386] vs. 28% [109 of 395]; adjusted difference, −10.1 percentage points; 95% confidence interval [CI], −15.9 to −4.3; P<0.001; MODIFY II: 16% [62 of 395] vs. 26% [97 of 378]; adjusted difference, −9.9 percentage points; 95% CI, −15.5 to −4.3; P<0.001) and was significantly lower with actoxumab plus bezlotoxumab than with placebo (MODIFY I: 16% [61 of 383] vs. 28% [109 of 395]; adjusted difference, −11.6 percentage points; 95% CI, −17.4 to −5.9; P<0.001; MODIFY II: 15% [58 of 390] vs. 26% [97 of 378]; adjusted difference, −10.7 percentage points; 95% CI, −16.4 to −5.1; P<0.001). In prespecified subgroup analyses (combined data set), rates of recurrent infection were lower in both groups that received bezlotoxumab than in the placebo group in subpopulations at high risk for recurrent infection or for an adverse outcome. The rates of initial clinical cure were 80% with bezlotoxumab alone, 73% with actoxumab plus bezlotoxumab, and 80% with placebo; the rates of sustained cure (initial clinical cure without recurrent infection in 12 weeks) were 64%, 58%, and 54%, respectively. The rates of adverse events were similar among these groups; the most common events were diarrhea and nausea. CONCLUSIONS Among participants receiving antibiotic treatment for primary or recurrent C. difficile infection, bezlotoxumab was associated with a substantially lower rate of recurrent infection than placebo and had a safety profile similar to that of placebo. The addition of actoxumab did not improve efficacy. (Funded by Merck; MODIFY I and MODIFY II ClinicalTrials.gov numbers, NCT01241552 and NCT01513239.

Biomimetic Liquid-Sieving through Covalent Molecular Meshes

The porin pores of biological cell membranes enable molecules to be sieved out selectively while water molecules traverse the channel in a single file. Imitating this streaming mechanism is a promising way to create artificial liquid-sieving membranes, but ultrathin molecular pores need to be produced in a large membrane format to be functional under high transmembrane pressures. Here we show that a membrane composed of a covalent molecular mesh can filter mixtures of small molecules in a liquid by the porin-like mechanism. Tetrahedral network formers are polymerized layer-by-layer on a nanoporous substrate to yield a thin layer of a covalent molecular network containing an array of molecular meshes grown by a pore-limited mechanism. Each of the meshes exhibits high water permeability, estimated to be greater than 2500 Lm-2 h-1. Glucose or larger molecules are selectively sieved out while the solvent and solutes smaller than glucose traverse the mesh. © 2016 American Chemical Society.

Toll-like receptor 3-induced immune response by poly(D,L-lactide-co-glycolide) nanoparticles for dendritic cell-based cancer immunotherapy

Hee Dong Han,1,* Yeongseon Byeon,1,* Tae Heung Kang,1 In Duk Jung,1 Jeong-Won Lee,2 Byung Cheol Shin,3 Young Joo Lee,4 Anil K Sood,5&ndash;7 Yeong-Min Park1 1Department of Immunology, School of Medicine, Konkuk University, Chungwondaero, Chungju-Si, Chungcheongbuk-Do, 2Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 3Bio/Drug Discovery Division, Korea Research Institute of Chemical Technology, Yuseong-gu, Daejeon, 4Department of Bioscience and Biotechnology, Sejong University, Kwang-Jin-Gu, Seoul, South Korea; 5Department of Gynecologic Oncology and Reproductive Medicine, 6Department of Cancer Biology, 7Center for RNA Interference and Non-coding RNA, The University of Texas MD Anderson Cancer Center, TX, USA *These authors contributed equally to this work Abstract: Dendritic cells (DCs) are potent professional antigen-presenting cells that are capable of initiating a primary immune response and activating T cells, and they play a pivotal role in the immune responses of the host to cancer. Prior to antigen presentation, efficient antigen and adjuvant uptake by DCs is necessary to induce their maturation and cytokine generation. Nanoparticles (NPs) are capable of intracellular delivery of both antigen and adjuvant to DCs. Here, we developed an advanced poly(D,L-lactide-co-glycolide) (PLGA)-NP encapsulating both ovalbumin (OVA) as a model antigen and polyinosinic-polycytidylic acid sodium salt (Toll-like receptor 3 ligand) as an adjuvant to increase intracellular delivery and promote DC maturation. The PLGA-NPs were taken up by DCs, and their uptake greatly facilitated major histocompatibility class I antigen presentation in vitro. Moreover, vaccination with PLGA-NP-treated DCs led to the generation of ovalbumin-specific CD8+ T cells, and the resulting antitumor efficacy was significantly increased in EG.7 and TC-1 tumor-bearing mice compared to control mice (P&lt;0.01). Taken together, these findings demonstrated that the PLGA-NP platform may be an effective method for delivering tumor-specific antigens or adjuvants to DCs. Keywords: cancer immunotherapy, PLGA nanoparticles, antigen deliver

Toll-like receptor 3-induced immune response by poly(D,L-lactide-co-glycolide) nanoparticles for dendritic cell-based cancer immunotherapy

Hee Dong Han,1,* Yeongseon Byeon,1,* Tae Heung Kang,1 In Duk Jung,1 Jeong-Won Lee,2 Byung Cheol Shin,3 Young Joo Lee,4 Anil K Sood,5&ndash;7 Yeong-Min Park1 1Department of Immunology, School of Medicine, Konkuk University, Chungwondaero, Chungju-Si, Chungcheongbuk-Do, 2Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 3Bio/Drug Discovery Division, Korea Research Institute of Chemical Technology, Yuseong-gu, Daejeon, 4Department of Bioscience and Biotechnology, Sejong University, Kwang-Jin-Gu, Seoul, South Korea; 5Department of Gynecologic Oncology and Reproductive Medicine, 6Department of Cancer Biology, 7Center for RNA Interference and Non-coding RNA, The University of Texas MD Anderson Cancer Center, TX, USA *These authors contributed equally to this work Abstract: Dendritic cells (DCs) are potent professional antigen-presenting cells that are capable of initiating a primary immune response and activating T cells, and they play a pivotal role in the immune responses of the host to cancer. Prior to antigen presentation, efficient antigen and adjuvant uptake by DCs is necessary to induce their maturation and cytokine generation. Nanoparticles (NPs) are capable of intracellular delivery of both antigen and adjuvant to DCs. Here, we developed an advanced poly(D,L-lactide-co-glycolide) (PLGA)-NP encapsulating both ovalbumin (OVA) as a model antigen and polyinosinic-polycytidylic acid sodium salt (Toll-like receptor 3 ligand) as an adjuvant to increase intracellular delivery and promote DC maturation. The PLGA-NPs were taken up by DCs, and their uptake greatly facilitated major histocompatibility class I antigen presentation in vitro. Moreover, vaccination with PLGA-NP-treated DCs led to the generation of ovalbumin-specific CD8+ T cells, and the resulting antitumor efficacy was significantly increased in EG.7 and TC-1 tumor-bearing mice compared to control mice (P&lt;0.01). Taken together, these findings demonstrated that the PLGA-NP platform may be an effective method for delivering tumor-specific antigens or adjuvants to DCs. Keywords: cancer immunotherapy, PLGA nanoparticles, antigen deliver