The human antibody fragment DIATHIS1 specific for CEACAM1 enhances natural killer cell cytotoxicity against melanoma cell lines in vitro

Several lines of evidence show that de novo expression of carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) is strongly associated with reduced disease-free survival of patients affected by metastatic melanoma. Previously published investigations report that homophilic interactions between CEACAM1 expressed on natural killer (NK) cells and tumors inhibit the NK cell-mediated killing independently of major histocompatibility complex class I recognition. This biological property can be physiologically relevant in metastatic melanoma because of the increased CEACAM1 expression observed on NK cells from some patients. Moreover, this inhibitory mechanism in many cases might hinder the efficacy of immunotherapeutic treatments of CEACAM1 malignancies because of tumor evasion by activated effector cells. In the present study, we designed an in vitro experimental model showing that the human single-chain variable fragment (scFv) DIATHIS1 specific for CEACAM1 is able to enhance the lytic machinery of NK cells against CEACAM1 melanoma cells. The coincubation of the scFv DIATHIS1 with CEACAM1 melanoma cells and NK-92 cell line significantly increases the cell-mediated cytotoxicity. Moreover, pretreatment of melanoma cells with scFv DIATHIS1 promotes the activation and the degranulation capacity of in vitro-expanded NK cells from healthy donors. It is interesting to note that the melanoma cell line MelC and the primary melanoma cells STA that respond better to DIATHIS1 treatment, express higher relative levels of CEACAM1-3L and CEACAM1-3S splice variants isoforms compared with Mel501 cells that are less responsive to DIATHIS1-induced NK cell-mediated cytotoxicity. Taken together, our results suggest that the fully human antibody fragment DIATHIS1 originated by biopanning approach from a phage antibody library may represent a relevant biotechnological platform to design and develop completely human antimelanoma therapeutics of biological origin

The MRN complex is transcriptionally regulated by MYCN during neural cell proliferation to control replication stress

The MRE11/RAD50/NBS1 (MRN) complex is a major sensor of DNA double strand breaks, whose role in controlling faithful DNA replication and preventing replication stress is also emerging. Inactivation of the MRN complex invariably leads to developmental and/or degenerative neuronal defects, the pathogenesis of which still remains poorly understood. In particular, NBS1 gene mutations are associated with microcephaly and strongly impaired cerebellar development, both in humans and in the mouse model. These phenotypes strikingly overlap those induced by inactivation of MYCN, an essential promoter of the expansion of neuronal stem and progenitor cells, suggesting that MYCN and the MRN complex might be connected on a unique pathway essential for the safe expansion of neuronal cells. Here, we show that MYCN transcriptionally controls the expression of each component of the MRN complex. By genetic and pharmacological inhibition of the MRN complex in a MYCN overexpression model and in the more physiological context of the Hedgehog-dependent expansion of primary cerebellar granule progenitor cells, we also show that the MRN complex is required for MYCN-dependent proliferation. Indeed, its inhibition resulted in DNA damage, activation of a DNA damage response, and cell death in a MYCN- and replication-dependent manner. Our data indicate the MRN complex is essential to restrain MYCN-induced replication stress during neural cell proliferation and support the hypothesis that replication-born DNA damage is responsible for the neuronal defects associated with MRN dysfunctions.Cell Death and Differentiation advance online publication, 12 June 2015; doi:10.1038/cdd.2015.81

In the matter of the request of Liberty Mutual Fire Insurance Company, a Massachusetts domestic stock insurance company, to redomesticate to the state of Wisconsin

Submitted by Nuzia Santos ([email protected]) on 2018-08-24T16:36:28Z No. of bitstreams: 1 Phosphatidyl Inositol 3 Kinase-Gamma Balances.pdf: 10035595 bytes, checksum: 5a61fb2c618990d4314d36db3868ee2e (MD5)Approved for entry into archive by Nuzia Santos ([email protected]) on 2018-08-24T16:44:27Z (GMT) No. of bitstreams: 1 Phosphatidyl Inositol 3 Kinase-Gamma Balances.pdf: 10035595 bytes, checksum: 5a61fb2c618990d4314d36db3868ee2e (MD5)Made available in DSpace on 2018-08-24T16:44:27Z (GMT). No. of bitstreams: 1 Phosphatidyl Inositol 3 Kinase-Gamma Balances.pdf: 10035595 bytes, checksum: 5a61fb2c618990d4314d36db3868ee2e (MD5) Previous issue date: 2018Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Vírus Respiratórios e do Sarampo. Rio de Janeiro, RJ, Brazil / Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Laboratório de Imunofarmacologia. Belo Horizonte, MG, Brazil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Laboratório de Imunofarmacologia. Belo Horizonte, MG, Brazil / Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Fisiologia e Biofísica. Laboratório de Imunologia e Mecânica Pulmonar. Belo Horizonte, MG, Brazil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Laboratório de Imunofarmacologia. Belo Horizonte, MG, Brazil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Hanseníase. Rio de Janeiro, RJ, Brazil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Hanseníase. Rio de Janeiro, RJ, Brazil / UNIFRANZ. Coordinación Nacional de Investigación. La Paz, Bolivia.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Morfologia. Belo Horizonte, MG, BrazilUniversidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Laboratório de Imunofarmacologia. Belo Horizonte, MG, Brazil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Laboratório de Imunofarmacologia. Belo Horizonte, MG, Brazil / Universidade de São Paulo. Departamento de Farmacologia. Laboratório de Inflamação e Dor. Universidade de São Paulo. Ribeirão Preto, SP, Brazil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Vírus Respiratórios e do Sarampo. Rio de Janeiro, RJ, Brazil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Laboratório de Imunofarmacologia. Belo Horizonte, MG, Brazil / Fundação Oswaldo Cruz. Instituto René Rachou. Laboratório de Imunologia de Doenças Virais. Belo Horizonte, MG, BrazilUniversidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Laboratório de Imunofarmacologia. Belo Horizonte, MG, Brazil / Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Biologia Geral. Belo Horizonte, MG, Brazil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Hanseníase. Rio de Janeiro, RJ, Brazil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Laboratório de RNA de Interferência Belo Horizonte, MG, Brazil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Vírus Respiratórios e do Sarampo. Rio de Janeiro, RJ, Brazil.Fundação Oswaldo Cruz. Instituto René Rachou. Laboratório de Imunologia de Doenças Virais. Belo Horizonte, MG, BrazilUniversidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Laboratório de Imunofarmacologia. Belo Horizonte, MG, Brazil / Universidade Federal de Minas Gerais. Faculdade de Farmácia. Departamento de Análises Clínicas e Toxicológicas. Belo Horizonte, MG, Brazil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Laboratório de Imunofarmacologia. Belo Horizonte, MG, Brazil / Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Fisiologia e Biofísica. Laboratório de Imunologia e Mecânica Pulmonar. Belo Horizonte, MG, Brazil.Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas. Departamento de Bioquímica e Imunologia. Laboratório de Imunofarmacologia. Belo Horizonte, MG, Brazil.Influenza A virus (IAV) infection causes severe pulmonary disease characterized by intense leukocyte infiltration. Phosphoinositide-3 kinases (PI3Ks) are central signaling enzymes, involved in cell growth, survival, and migration. Class IB PI3K or phosphatidyl inositol 3 kinase-gamma (PI3Kγ), mainly expressed by leukocytes, is involved in cell migration during inflammation. Here, we investigated the contribution of PI3Kγ for the inflammatory and antiviral responses to IAV. PI3Kγ knockout (KO) mice were highly susceptible to lethality following infection with influenza A/WSN/33 H1N1. In the early time points of infection, infiltration of neutrophils was higher than WT mice whereas type-I and type-III IFN expression and p38 activation were reduced in PI3Kγ KO mice resulting in higher viral loads when compared with WT mice. Blockade of p38 in WT macrophages infected with IAV reduced levels of interferon-stimulated gene 15 protein to those induced in PI3Kγ KO macrophages, suggesting that p38 is downstream of antiviral responses mediated by PI3Kγ. PI3Kγ KO-derived fibroblasts or macrophages showed reduced type-I IFN transcription and altered pro-inflammatory cytokines suggesting a cell autonomous imbalance between inflammatory and antiviral responses. Seven days after IAV infection, there were reduced infiltration of natural killer cells and CD8+ T lymphocytes, increased concentration of inflammatory cytokines in bronchoalveolar fluid, reduced numbers of resolving macrophages, and IL-10 levels in PI3Kγ KO. This imbalanced environment in PI3Kγ KO-infected mice culminated in enhanced lung neutrophil infiltration, reactive oxygen species release, and lung damage that together with the increased viral loads, contributed to higher mortality in PI3Kγ KO mice compared with WT mice. In humans, we tested the genetic association of disease severity in influenza A/H1N1pdm09-infected patients with three potentially functional PIK3CG single-nucleotide polymorphisms (SNPs), rs1129293, rs17847825, and rs2230460. We observed that SNPs rs17847825 and rs2230460 (A and T alleles, respectively) were significantly associated with protection from severe disease using the recessive model in patients infected with influenza A(H1N1)pdm09. Altogether, our results suggest that PI3Kγ is crucial in balancing antiviral and inflammatory responses to IAV infection

Use of phosphorus fertilization and mycorrhization as strategies for reducingcopper toxicity in young grapevines.

Established vineyard soils may have high copper (Cu) contents due to the ongoing foliar applications of copper-based fungicides. In viticulture, the replacement of old vineyards with new vines is common practice, however,limited by Cu excess in soil and its toxicity to young grapevines. The application of phosphorus (P) and ar-buscular mycorrhizal fungi (AMF) inoculation are potential strategies to reduce Cu toxicity to young grapevines.This study aimed to assess the effects of phosphorus fertilization and AMF (Rhizophagus clarus) inoculation ongrowth and physiological parameters of young grapevines grown in soil with high Cu content. The experimentwas conducted in a greenhouse, where natural grassland soil was artificially contaminated by the addition of60 mg kg−1Cu. The soils were treated with and without AMF inoculation, combined with additions of 0, 40 and100 mg P kg−1. After 90 days of cultivation, grapevine plants were assessed for chlorophyllafluorescence,photosynthetic pigment contents, superoxide dismutase (SOD) activity, plant height, plant biomass, and con-centrations of Cu and P in roots and shoots. Phosphorus fertilization promoted increases in seedling growth(related to the increase of total P concentration in roots and shoots), soluble Pi concentration in leaves, and thequantum yield of the PSII (YII) (associated with a reduction in shoot Cu concentration). The AMF inoculationincreased the concentration of P in roots and shoots, soluble Pi in leaves and electron transport rate (ETR).Phosphorus fertilization and inoculation of grapevines with AMF are strategies capable of reducing Cu toxicity inyoung grapevines

GZMKhigh CD8+ T effector memory cells are associated with CD15high neutrophil abundance in non-metastatic colorectal tumors and predict poor clinical outcome.

CD8(+) T cells are a major prognostic determinant in solid tumors, including colorectal cancer (CRC). However, understanding how the interplay between different immune cells impacts on clinical outcome is still in its infancy. Here, we describe that the interaction of tumor infiltrating neutrophils expressing high levels of CD15 with CD8(+) T effector memory cells (T(EM)) correlates with tumor progression. Mechanistically, stromal cell-derived factor-1 (CXCL12/SDF-1) promotes the retention of neutrophils within tumors, increasing the crosstalk with CD8(+) T cells. As a consequence of the contact-mediated interaction with neutrophils, CD8(+) T cells are skewed to produce high levels of GZMK, which in turn decreases E-cadherin on the intestinal epithelium and favors tumor progression. Overall, our results highlight the emergence of GZMK(high) CD8(+) T(EM) in non-metastatic CRC tumors as a hallmark driven by the interaction with neutrophils, which could implement current patient stratification and be targeted by novel therapeutics

Anticancer activity of a sub-fraction of dichloromethane extract of Strobilanthes crispus on human breast and prostate cancer cells in vitro

<p>Abstract</p> <p>Background</p> <p>The leaves of <it>Strobilanthes crispus </it>(<it>S. crispus</it>) which is native to the regions of Madagascar to the Malay Archipelago, are used in folk medicine for their antidiabetic, diuretic, anticancer and blood pressure lowering properties. Crude extracts of this plant have been found to be cytotoxic to human cancer cell lines and protective against chemically-induced hepatocarcinogenesis in rats. In this study, the cytotoxicity of various sub-fractions of dichloromethane extract isolated from the leaves of <it>S. crispus </it>was determined and the anticancer activity of one of the bioactive sub-fractions, SC/D-F9, was further analysed in breast and prostate cancer cell lines.</p> <p>Methods</p> <p>The dichloromethane extract of <it>S. crispus </it>was chromatographed on silica gel by flash column chromatography. The ability of the various sub-fractions obtained to induce cell death of MCF-7, MDA-MB-231, PC-3 and DU-145 cell lines was determined using the LDH assay. The dose-response effect and the EC₅₀values of the active sub-fraction, SC/D-F9, were determined. Apoptosis was detected using Annexin V antibody and propidium iodide staining and analysed by fluorescence microscopy and flow cytometry, while caspase 3/7 activity was detected using FLICA caspase inhibitor and analysed by fluorescence microscopy.</p> <p>Results</p> <p>Selected sub-fractions of the dichloromethane extract induced death of MCF-7, MDA-MB-231, PC-3 and DU-145 cells. The sub-fraction SC/D-F9, consistently killed breast and prostate cancer cell lines with low EC₅₀values but is non-cytotoxic to the normal breast epithelial cell line, MCF-10A. SC/D-F9 displayed relatively higher cytotoxicity compared to tamoxifen, paclitaxel, docetaxel and doxorubicin. Cell death induced by SC/D-F9 occurred via apoptosis with the involvement of caspase 3 and/or 7.</p> <p>Conclusions</p> <p>A dichloromethane sub-fraction of <it>S. crispus </it>displayed potent anticancer activities <it>in vitro </it>that can be further exploited for the development of a potential therapeutic anticancer agent.</p

Bacterial Pili exploit integrin machinery to promote immune activation and efficient blood-brain barrier penetration

Group B Streptococcus (GBS) is the leading cause of meningitis in newborn infants. Bacterial cell surface appendages, known as pili, have been recently described in streptococcal pathogens, including GBS. The pilus tip adhesin, PilA, contributes to GBS adherence to blood-brain barrier (BBB) endothelium; however, the host receptor and the contribution of PilA in central nervous system (CNS) disease pathogenesis are unknown. Here we show that PilA binds collagen, which promotes GBS interaction with the α2β1 integrin resulting in activation of host chemokine expression and neutrophil recruitment during infection. Mice infected with the PilA-deficient mutant exhibit delayed mortality, a decrease in neutrophil infiltration and bacterial CNS dissemination. We find that PilA-mediated virulence is dependent on neutrophil influx as neutrophil depletion results in a decrease in BBB permeability and GBS–BBB penetration. Our results suggest that the bacterial pilus, specifically the PilA adhesin, has a dual role in immune activation and bacterial entry into the CNS