Carcinoma-derived interleukin-8 disorients dendritic cell migration without impairing T-cell stimulation

BACKGROUND: Interleukin-8 (IL-8, CXCL8) is readily produced by human malignant cells. Dendritic cells (DC) both produce IL-8 and express the IL-8 functional receptors CXCR1 and CXCR2. Most human colon carcinomas produce IL-8. IL-8 importance in malignancies has been ascribed to angiogenesis promotion. PRINCIPAL FINDINGS: IL-8 effects on human monocyte-derived DC biology were explored upon DC exposure to recombinant IL-8 and with the help of an IL-8 neutralizing mAb. In vivo experiments were performed in immunodeficient mice xenografted with IL-8-producing human colon carcinomas and comparatively with cell lines that do not produce IL-8. Allogenic T lymphocyte stimulation by DC was explored under the influence of IL-8. DC and neutrophil chemotaxis were measured by transwell-migration assays. Sera from tumor-xenografted mice contained increasing concentrations of IL-8 as the tumors progress. IL-8 production by carcinoma cells can be modulated by low doses of cyclophosphamide at the transcription level. If human DC are injected into HT29 or CaCo2 xenografted tumors, DC are retained intratumorally in an IL-8-dependent fashion. However, IL-8 did not modify the ability of DC to stimulate T cells. Interestingly, pre-exposure of DC to IL-8 desensitizes such cells for IL-8-mediated in vitro or in vivo chemoattraction. Thereby DC become disoriented to subsequently follow IL-8 chemotactic gradients towards malignant or inflamed tissue. CONCLUSIONS: IL-8 as produced by carcinoma cells changes DC migration cues, without directly interfering with DC-mediated T-cell stimulation

Preemptive-TIPS improves outcome in high-risk variceal bleeding : An observational study

Objective Patients admitted with acute variceal bleeding (AVB) and Child Pugh C score (CP\u2010C) or Child Pugh B plus active bleeding at endoscopy (CP\u2010B+AB) are at high risk for treatment failure, rebleeding and mortality. Preemptive TIPS (p\u2010TIPS) has been shown to improve survival in these patients but its use in clinical practice has been challenged and not routinely incorporated. The present study aimed to further validate the role of preemptive TIPS in a large number of high\u2010risk patients. Design Multicenter, international, observational study including 671 patients from 34 centers admitted for AVB and high\u2010risk of treatment failure. Patients were managed according to current guidelines and use of drugs and endoscopic therapy (D+E) or preemptive TIPS (p\u2010TIPS) was based on individual center policy. Results p\u2010TIPS in the setting of AVB is associated with a lower mortality in Child C patients compared to D+E (1 year mortality 22% vs 47% in D+E group; P=0.002). Mortality rate in CP\u2010B+AB patients was low and p\u2010TIPS did not improve it. In CP\u2010C and CP\u2010B +AB patients, p\u2010TIPS reduces treatment failure and rebleeding (1 year CIF\u2010probability of remaining free of the composite endpoint: 92% vs 74% in the D+E group; P=0.017), development of \u201cde novo\u201d or worsening of previous ascites without increasing rates of hepatic encephalopathy. Conclusion p\u2010TIPS must be the treatment of choice in CP\u2010C patients with AVB. Due to the strong benefit in preventing further bleeding and ascites, p\u2010TIPS could be a good treatment strategy for CP\u2010B+AB patients

Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study

Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe

Cyclin A1 protein shows haplo-insufficiency for normal fertility in male mice

In higher eukaryotes, the cyclins constitute a family of proteins involved in progression through the cell cycle. The cyclin A1 gene (Ccna1) is expressed during meiosis and is required for spermatogenesis. Targeted disruption of the Ccna1 gene with a LacZ reporter gene has allowed us to study the expression pattern of this gene in more detail. We have confirmed expression in mouse pre-meiotic spermatocytes and also detected expression in the accessory olfactory bulb, hippocampus and amygdala of the adult brain. We have also found that the amount of cyclin A1 protein influences the fertility of male mice and its action is modulated by genetic background. On an outbred genetic background (129S6/SvEv × MF1), Ccna1tm1Col -/- animals are sterile due to spermatogenic arrest prior to the first meiotic division while Ccna1tm1Col +/- mice show reduced sperm production and fertility. This is even more pronounced on an inbred genetic background (129S6/SvEv) where Ccna1tm1Col +/- male mice are sterile due to a severe reduction in the total number of sperm

Delivery of immunostimulatory monoclonal antibodies by encapsulated hybridoma cells

Immunostimulatory monoclonal antibodies are immunoglobulins directed toward surface proteins of immune system cells that augment the immune response against cancer in a novel therapeutic fashion. Exogenous administration of the recombinant humanized immunoglobulins is being tested in clinical trials with agents of this kind directed at a variety of immune-controlling molecular targets. In this study, the encapsulation of antibody-producing hybridoma cells was tested in comparison with the systemic administration of monoclonal antibodies. Hybridomas producing anti-CD137 and anti-OX40 mAb were encapsulated in alginate to generate microcapsules containing viable cells that secrete antibody. Immobilized cells in vitro were able to release the rat immunoglobulin produced by the hybridomas into the supernatant. Microcapsules were implanted by injection into the subcutaneous tissue of mice and thereby provided a platform for viable secreting cells, which lasted for more than 1 week. The pharmacokinetic profile of the rat monoclonal antibodies following microcapsule implantation was similar to that attained following an intraperitoneal administration of the purified antibodies. The rat-mouse hybridoma cells did not engraft as tumors in immunocompetent mice, while they lethally xenografted in immunodeficient mice, if not microencapsulated. The antitumor therapeutic activity of the strategy was studied on established CT26 colon carcinomas resulting in complete tumor eradication in an elevated fraction of cases and strong tumor-specific CTL responses with either anti-CD137 or anti-OX40 producing hybridomas, thus offering proof of the concept. This form of administration permitted combinations of more than one immunostimulatory monoclonal antibody to exploit the synergistic effects such as those known to be displayed by anti-CD137 and anti-OX40 mAb

Keratin 7 promoter selectively targets transgene expression to normal and neoplastic pancreatic ductal cells in vitro and in vivo

Keratin 7 is expressed in simple epithelia but is expressed at low or undetectable levels in gastrointestinal epithelial cells. In the pancreas, it is present in ductal but not in acinar cells. K7 mRNA is overexpressed in pancreatic cancers. Here we use luciferase reporter assays to analyze the tissue-specific regulatory elements of murine keratin 7 (Krt7) promoter in vitro and in vivo. All elements required for appropriate cell and tissue specificity in reporter assays are present within the Krt7 -234 bp sequence. This fragment appears more selective to pancreatic ductal cells than the Krt19 promoter. GC-rich sequences corresponding to putative Sp1, AP-2 binding sites are essential for in vitro activity. Krt7-LacZ transgenic mice were generated to analyze in vivo activity. Sequences located 1.5 or 0.25 kb upstream of the transcription initiation site drive reporter expression to ductal, but not acinar, cells in transgenic mice. LacZ mRNA was detected in the pancreas as well as in additional epithelial tissues - such as the intestine and the lung - using both promoter constructs. An AdK7Luc adenovirus was generated to assess targeting selectivity in vivo by intravenous injection to immunocompetent mice and in a xenograft model of pancreatic cancer. The -0.25 kb region showed pancreatic selectivity, high activity in pancreatic cancers, and sustained transgene expression in xenografts. In conclusion, the krt7 promoter is useful to target pancreatic ductal adenocarcinoma cells in vitro and in vivo. © FASEB.This work was supported, in part, by grants from Plan Nacional de I+D (SAF2001-0420, SAF2004-01137, and SAF2007-60860), Acción Especial de Genómica (GEN2001-4748-c05-01), CIRIT (Generalitat de Catalunya) (SGR-00410), Marató de TV-3, and Biomed Program (QLG-CT-2002-01196) to F.X.R., and grants BIO2005-08682-C03-02 from the Spanish Ministry of Education and Science and SGR0500008 from the Generalitat de Catalunya to C.F. The group of C.F. is also partially funded by CIBERER, Instituto de Salud Carlos III. W.H.I.M. and F.J.D.S. were supported by a Wellcome Trust Senior Research Fellowship in Basic Biomedical Science (to W.H.I.M.). M.H. was a predoctoral fellow (BEFI) at the Instituto de Salud Carlos III. A.J. was supported by a predoctoral fellowship (FPU) granted by the Spanish Ministry of Education and Science. I.A. was supported by a postdoctoral fellowship from the Basque government.Peer Reviewe

Delivery of immunostimulatory monoclonal antibodies by encapsulated hybridoma cells

Immunostimulatory monoclonal antibodies are immunoglobulins directed toward surface proteins of immune system cells that augment the immune response against cancer in a novel therapeutic fashion. Exogenous administration of the recombinant humanized immunoglobulins is being tested in clinical trials with agents of this kind directed at a variety of immune-controlling molecular targets. In this study, the encapsulation of antibody-producing hybridoma cells was tested in comparison with the systemic administration of monoclonal antibodies. Hybridomas producing anti-CD137 and anti-OX40 mAb were encapsulated in alginate to generate microcapsules containing viable cells that secrete antibody. Immobilized cells in vitro were able to release the rat immunoglobulin produced by the hybridomas into the supernatant. Microcapsules were implanted by injection into the subcutaneous tissue of mice and thereby provided a platform for viable secreting cells, which lasted for more than 1 week. The pharmacokinetic profile of the rat monoclonal antibodies following microcapsule implantation was similar to that attained following an intraperitoneal administration of the purified antibodies. The rat-mouse hybridoma cells did not engraft as tumors in immunocompetent mice, while they lethally xenografted in immunodeficient mice, if not microencapsulated. The antitumor therapeutic activity of the strategy was studied on established CT26 colon carcinomas resulting in complete tumor eradication in an elevated fraction of cases and strong tumor-specific CTL responses with either anti-CD137 or anti-OX40 producing hybridomas, thus offering proof of the concept. This form of administration permitted combinations of more than one immunostimulatory monoclonal antibody to exploit the synergistic effects such as those known to be displayed by anti-CD137 and anti-OX40 mAb

Therapeutic antitumor efficacy of anti-CD137 agonistic monoclonal antibody in mouse models of myeloma

PURPOSE: Eradication of post-treatment residual myeloma cells is needed to prevent relapses, and immunostimulatory monoclonal antibodies (mAb) such as anti-CD137, CTLA-4, CD40, etc., which enhance the immune response against malignancies, represent a means of achieving this purpose. This study explores anti-CD137 mAbs for multiple myeloma treatment in preclinical models of the disease because they safely augment tumor immunity and are in clinical trials for other cancers. EXPERIMENTAL DESIGN: The antitumor effect of anti-CD137 mAb on mouse plasmacytomas derived from HOPC and NS0 cell lines was studied and compared with that of anti-CTLA-4, anti-CD40, and anti-ICAM-2 mAbs. The antitumor effect of anti-CD137 mAb was also examined in a mouse syngeneic disseminated myeloma (5TGM1) model, which more closely resembles human multiple myeloma. Depletions of specific cell populations and gene-targeted mice were used to unravel the requirements for tumor rejection. RESULTS: Agonistic mAb against CD137 and blocking anti-CTLA-4 mAb showed activity against i.p. HOPC tumors, resulting in extended survival of mice that also became immune to rechallenge. Anti-CD137 mAbs induced complete eradications of established s.c. NS0-derived tumors that were dependent on IFN-gamma, natural killer cells, and CD8(+) T lymphocytes. Natural killer cells accumulated in tumor draining lymph nodes and showed increased IFN-gamma production. Antitumor efficacy of anti-CD137 mAb was preserved in CD28-deficient mice despite the fact that CD28 signaling increases the expression of CD137 on CD8(+) T cells. Importantly, anti-CD137 mAb treatment significantly decreased systemic tumor burden in the disseminated 5TGM1 model. CONCLUSIONS: The immune-mediated antitumor activity of anti-CD137 mAb in mouse models holds promise for myeloma treatment in humans

Proinflammatory signals are insufficient to drive definitive hematopoietic specification of human HSCs in vitro.

Recent studies in zebrafish and mice have revealed that proinflammatory signaling is a positive regulator of definitive hematopoietic development. Whether proinflammatory signaling also regulates human hematopoietic specification remains unknown. Here, we explored the impact of the proinflammatory cytokines tumor necrosis factor-α (TNFα), interferon-γ (IFNγ), and interleukin-1β (IL1β) on in vitro hematopoietic differentiation using human pluripotent stem cells. Gene expression analysis and enzyme-linked immunosorbent assay revealed the absence of a proinflammatory signature during hematopoietic development of human pluripotent stem cells. Functionally, the emergence of hemogenic endothelial progenitors (CD31+CD34+CD45- or CD34+CD43-CD73-) and hematopoietic cells (CD43+CD45+) was not affected by treatment with increasing doses of TNFα, IFNγ, and IL1β irrespective of the developmental window or the differentiation protocol used (embryoid body or OP9 co-culture based). Similarly, knockdown of endogenous NF-kB signaling had no impact on hematopoietic differentiation of human pluripotent stem cells. This study serves as a demonstration that TNFα, IFNγ, and IL1β signals do not improve hematopoietic differentiation of human pluripotent stem cells using current protocols and suggests that proinflammatory signaling is insufficient to drive definitive hematopoietic specification of human hematopoietic stem cells in vitro.This work was supported by the European Research Council (646903 to PM) and the Spanish Ministry of Economy and Competitiveness (SAF2013-43072R to AG, SAF2013-43065R to PM, and ISCIII/FEDER-PI14/01119 to CB). CB is supported by a Miguel Servet contract (CPII13/00011). AG is supported by the Ramon y Cajal Program (RyC-2013-13221). PM also acknowledges support from Obra Social La Caixa-Fundacio Josep Carreras and Generalitat de Catalunya (SGR330)

Circulating regulatory T cells from breast cancer patients in response to neoadjuvant chemotherapy

Background: Immune escape of tumor cells is a new hallmark of cancer in general, and breast cancer, in particular. Previous studies have demonstrated that the immunological profile in peripheral blood may be a prognostic and/or predictive biomarker in breast cancer. Thus, higher number of regulatory T cells (Tregs) in blood from patients with breast cancer has been reported in relation to normal donors. In the present study, we planned to evaluate the changes in different cell populations in peripheral blood: neutrophils, monocytes and lymphocytes, as well as lymphocyte subpopulations [natural killer (NK), B lymphocytes, T lymphocytes, both CD4(+) and CD8(+), and Tregs] from patients with local breast cancer (both Her2(+) and Her2(-)), before, during and after neoadjuvant chemotherapy.Methods: We have employed flow cytometry for the cell analysis of fresh samples obtained before and whilst the neoadjuvant treatment was accomplished. We have studied 50 successive patients from the Breast Cancer Unit of the Virgen Macarena University Hospital during 2 years.Results: Neoadjuvant chemotherapy induced a significant reduction in B cells, especially in Her2(-) patients, and a reduction in NK cells. CD4(+) T cells decreased, whereas CD8(+) cells only decreased in Her2(-) patients. Tregs were also diminished, especially in Her2(+) patients, in response to treatment. Thus, higher CD8/Treg ratio was observed in Her2(+) patients. A higher percentage of Her2(+) patients (66.6%) achieved complete response than Her2(-) patients (27.5%). Monocytes and neutrophils were not changed in peripheral blood.Conclusions: Even though the decrease in B cells and NK cells in response to chemotherapy may be deleterious in the neoadjuvant treatment of breast cancer, the decrease in Tregs and CD4 T cells, but not CD8 T cells, increasing the CD8/Treg ratio, especially in Her2(+) patients, may reveal a new tool to monitor the immune response in breast cancer treated with chemotherapy in the neoadjuvant setting