Retinoblastoma (Rb) is the most common primary intraocular tumor in children. Local treatment of the intraocular disease is usually effective if diagnosed early; however advanced Rb can metastasize ...through routes that involve invasion of the choroid, sclera and optic nerve or more broadly via the ocular vasculature. Metastatic Rb patients have very high mortality rates. While current therapy for Rb is directed toward blocking tumor cell division and tumor growth, there are no specific treatments targeted to block Rb metastasis. Two such targets are matrix metalloproteinases-2 and -9 (MMP-2, -9), which degrade extracellular matrix as a prerequisite for cellular invasion and have been shown to be involved in other types of cancer metastasis. Cancer Clinical Trials with an anti-MMP-9 therapeutic antibody were recently initiated, prompting us to investigate the role of MMP-2, -9 in Rb metastasis.
We compare MMP-2, -9 activity in two well-studied Rb cell lines: Y79, which exhibits high metastatic potential and Weri-1, which has low metastatic potential. The effects of inhibitors of MMP-2 (ARP100) and MMP-9 (AG-L-66085) on migration, angiogenesis, and production of immunomodulatory cytokines were determined in both cell lines using qPCR, and ELISA. Cellular migration and potential for invasion were evaluated by the classic wound-healing assay and a Boyden Chamber assay.
Our results showed that both inhibitors had differential effects on the two cell lines, significantly reducing migration in the metastatic Y79 cell line and greatly affecting the viability of Weri-1 cells. The MMP-9 inhibitor (MMP9I) AG-L-66085, diminished the Y79 angiogenic response. In Weri-1 cells, VEGF was significantly reduced and cell viability was decreased by both MMP-2 and MMP-9 inhibitors. Furthermore, inhibition of MMP-2 significantly reduced secretion of TGF-β1 in both Rb models.
Collectively, our data indicates MMP-2 and MMP-9 drive metastatic pathways, including migration, viability and secretion of angiogenic factors in Rb cells. These two subtypes of matrix metalloproteinases represent new potential candidates for targeted anti-metastatic therapy for Rb.
Sulfuric acid (H₂SO₄), formed from oxidation of sulfur dioxide (SO₂) emitted during fossil fuel combustion, is a major precursor of new airborne particles, which have well-documented detrimental ...effects on health, air quality, and climate. Another precursor is methanesulfonic acid (MSA), produced simultaneously with SO₂ during the atmospheric oxidation of organosulfur compounds (OSCs), such as dimethyl sulfide. In the present work, a multidisciplinary approach is used to examine how contributions of H₂SO₄ and MSA to particle formation will change in a large coastal urban area as anthropogenic fossil fuel emissions of SO₂ decline. The 3-dimensional University of California Irvine–California Institute of Technology airshed model is used to compare atmospheric concentrations of gas phase MSA, H₂SO₄, and SO₂ under current emissions of fossil fuel-associated SO₂ and a best-case futuristic scenario with zero fossil fuel sulfur emissions. Model additions include results from (i) quantum chemical calculations that clarify the previously uncertain gas phase mechanism of formation of MSA and (ii) a combination of published and experimental estimates of OSC emissions, such as those from marine, agricultural, and urban processes, which include pet waste and human breath. Results show that in the zero anthropogenic SO₂ emissions case, particle formation potential from H₂SO₄ will drop by about two orders of magnitude compared with the current situation. However, particles will continue to be generated from the oxidation of natural and anthropogenic sources of OSCs, with contributions from MSA and H₂SO₄ of a similar order of magnitude. This could be particularly important in agricultural areas where there are significant sources of OSCs.
Vitreous seeding remains the primary reason for treatment failure in eyes with retinoblastoma (Rb). Systemic and intra-arterial chemotherapy, each with its own inherent set of complications, have ...improved salvage rates for eyes with advanced disease, but the location and biology of vitreous seeds present a fundamental challenge in developing treatments with minimal toxicity and risk. The aim of this study was to target the platelet-derived growth factor (PDGF)- PDGF-receptor β (PDGFRβ) signaling pathway and investigate its role in the growth of Rb seeds, apoptotic activity, and invasive potential.
We performed ex vivo analyses on vitreous samples from Rb patients that underwent enucleation and from patient-derived xenografts. These samples were evaluated by quantitative PCR, immunohistochemistry, and ELISA. The effects of disruption of the PDGF-PDGFRβ signaling pathway, both by pharmacologic and genomic knockdown approaches, were evaluated in vitro by cell proliferation and apoptotic assays, quantitative PCR analyses, Western blotting, flow cytometry, and imaging flow cytometry. A three-dimensional cell culture system was generated for in-depth study of Rb seeds.
Our results demonstrated that PDGFRβ signaling is active in the vitreous of Rb patients and patient-derived xenografts, sustaining growth and survival in an AKT-, MDM2-, and NF-κB-dependent manner. The novel three-dimensional cell culture system mimics Rb seeds, as the in vitro generated spheroids have similar morphologic features to Rb seeds and mimicked their natural physiology.
Targeting the PDGFRβ pathway in vitro reduces Rb cell growth, survival, and invasiveness and could augment current therapies. This represents a novel signaling pathway for potential targeted therapy to further improve ocular survival in advanced Rb.
The Westmoreland area is located in the southern part of the McArthur Basin (Australia) and hosts several uranium (U) deposits and prospects. Previous studies proposed that U mineralisation formed ...under conditions similar to the unconformity-related U deposits of the Alligator Rivers Uranium Field (ARUF), located north of the McArthur Basin. Detailed mineralogical, geochemical and geochronological studies on mineralised intervals from the Redtree, Junnagunna, and Huarabagoo deposits, and integration with previous studies, identified at least six generations of uranium oxides. These formed between ca. 1680 and 350 Ma, highlighting protracted mobility of U over 1.3 Ga. Each generation of uranium oxide has a specific chemical composition, indicating variable physicochemical conditions for their formation throughout this period. Although the 1680-Ma mineralising event formed at the same time and with similar mineralising fluids as the unconformity-related U deposits from the ARUF, the physicochemical conditions differed between the two areas. Deposits of the Westmoreland area lack the typical Mg– and B–metasomatism of the unconformity-related U deposits in the ARUF: in the Westmoreland area, the chlorite is Mg-poor and no B minerals are observed, whereas the ARUF is marked by Mg-rich chlorite, between clinochlore and Mg–amesite, Mg–foitite, and alumino–phosphate–sulfate minerals. The chondrite-normalised REE patterns of uranium oxides are enriched in light rare earth elements (LREEs) or flat, compared with the typical bell shape of the unconformity-related U deposits. Chlorite thermometry indicates significantly higher temperature conditions (> 300 °C) than in the ARUF for the early U stages. Based on these results, mineralisation in the Westmoreland area is thus significantly different from the unconformity-related U deposits in the ARUF and in other sedimentary basins. Collectively, the data point towards atypical ore-forming processes for basin-related U deposits in the Westmoreland area, but show some similarities with those known in the U deposits of the Otish Basin (Québec, Canada).
Background & Aims: Interleukin 10 (IL-10) is an anti-inflammatory, immunomodulatory cytokine that regulates mucosal inflammation. This study evaluated the safety, tolerance, and efficacy of ...recombinant human IL-10 (rhuIL-10) for mild to moderately active Crohn's disease. Methods: We conducted a 24-week multicenter, prospective, randomized, double-blind, placebo-controlled, and sequential-escalating-dose study. Ninetyfive patients with Crohn's Disease Activity Index of 200–350, not presently undergoing corticosteroid, mesalamine, or immunosuppressive therapy, were treated with subcutaneous rhuIL-10 (1, 5, 10, or 20 μg/kg) or placebo once daily for 28 consecutive days. Patients were followed up for 20 weeks after treatment. Evaluation of safety and tolerance was the first objective, and efficacy was the second objective. Results: Adverse effects were dose-related, mild-to-moderate in severity, and reversible. Asymptomatic and reversible anemia and thrombocytopenia were observed at higher doses. No withdrawal or delayed adverse effects were evident during 20 weeks of follow-up. At the end of treatment (day 29), intent-to-treat analysis showed that 23.5% (confidence interval CI, 6.8%–49.9%) of patients receiving 5 μg/kg rhuIL-10 experienced clinical remission and endoscopic improvement; 0% (CI, 0%–14.8%) of patients in the placebo group did. Higher doses of recombinant human IL-10 were less effective than 5 μg/kg. No rhuIL-10 serum accumulation and no antibody against IL-10 were detected after 4 weeks. Conclusions: Subcutaneous rhuIL-10 administered daily for 28 days to patients with mild to moderately active Crohn's disease is safe, well-tolerated, and shows clinical and endoscopic improvement.
GASTROENTEROLOGY 2000;119:1473-1482
Microbial colonization of glacial ice surfaces incurs feedbacks which affect the melting rate of the ice surface. Ecosystems formed as microbe–mineral aggregates termed cryoconite locally reduce ice ...surface albedo and represent foci of biodiversity and biogeochemical cycling. Consequently, greater understanding the ecological processes in the formation of functional cryoconite ecosystems upon glacier surfaces is sought. Here, we present the first bacterial biogeography of an ice cap, evaluating the respective roles of dispersal, environmental and biotic filtration occurring at local scales in the assembly of cryoconite microbiota. 16S rRNA gene amplicon semiconductor sequencing of cryoconite colonizing a Svalbard ice cap coupled with digital elevation modelling of physical parameters reveals the bacterial community is dominated by a ubiquitous core of generalist taxa, with evidence for a moderate pairwise distance–decay relationship. While geographic position and melt season duration are prominent among environmental predictors of community structure, the core population of taxa appears highly influential in structuring the bacterial community. Taxon co‐occurrence network analysis reveals a highly modular community structured by positive interactions with bottleneck taxa, predominantly Actinobacteria affiliated to isolates from soil humus. In contrast, the filamentous cyanobacterial taxon (assigned to Leptolyngbya/Phormidesmis pristleyi) which dominates the community and binds together granular cryoconite are poorly connected to other taxa. While our study targeted one ice cap, the prominent role of generalist core taxa with close environmental relatives across the global cryosphere indicate discrete roles for cosmopolitan Actinobacteria and Cyanobacteria as respective keystone taxa and ecosystem engineers of cryoconite ecosystems colonizing ice caps.
Broadly neutralizing antibodies (bnAbs) against the N332 supersite of the HIV envelope (Env) trimer are the most common bnAbs induced during infection, making them promising leads for vaccine design. ...Wild-type Env glycoproteins lack detectable affinity for supersite-bnAb germline precursors and are therefore unsuitable immunogens to prime supersite-bnAb responses. We employed mammalian cell surface display to design stabilized Env trimers with affinity for germline-reverted precursors of PGT121-class supersite bnAbs. The trimers maintained native-like antigenicity and structure, activated PGT121 inferred-germline B cells ex vivo when multimerized on liposomes, and primed PGT121-like responses in PGT121 inferred-germline knockin mice. Design intermediates have levels of epitope modification between wild-type and germline-targeting trimers; their mutation gradient suggests sequential immunization to induce bnAbs, in which the germline-targeting prime is followed by progressively less-mutated design intermediates and, lastly, with native trimers. The vaccine design strategies described could be utilized to target other epitopes on HIV or other pathogens.
•Developed mammalian cell display to design germline-targeting native-like trimers•Germline-targeting trimers retain native-like antigenicity and structure•Germline-targeting trimers prime glycan-dependent HIV bnAb responses in knockin mice•Designed boosting schemes intended to induce bnAbs
Elicitation of broadly neutralizing antibodies (bnAbs) is a critical HIV vaccine goal. Steichen et al. have developed immunogens that prime germline-precursor B cells for the bnAb PGT121 and can therefore initiate bnAb induction. The authors have also designed boosting immunogens to shepherd the antibody maturation to develop bnAbs.
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