Search

OAd-MSC WT and OAd-MSC TLR4−/− show similar expression of cell membrane receptors in vitro

OAd-MSC MyD88−/−

Cancer immunotherapy aims to activate the immune system. Some immunotherapeutic agents can be loaded in carrier cells for delivering to the tumors. However, a challenge with cell-based therapies is the selection of the appropriate cells to produce effective clinical outcomes. We hypothesize that therapies based on cells presenting a natural low proinflammatory profile (“silent cells”) in the peripheral blood would result in better antitumor responses by increasing their homing to the tumor site. We studied our hypothesis in an immunotherapy model consisting of mesenchymal stromal cells (MSCs) carrying oncolytic adenoviruses for the treatment of immunocompetent mice. Toll-like receptor signaling–deficient cells (TLR4, TLR9, or MyD88 knockout) were used as “silent cells,” while regular MSCs were used as control. Although in vitro migration was similar in regular and knockout carrier cells, in vivo tumor homing of silent cells was significantly higher after systemic administration. This better homing to the tumor site was highly related to the mild immune response triggered by these silent cells in peripheral blood. As a result, the use of silent cells significantly improved the antitumor efficacy of the treatment in comparison with the use of regular MSCs. While cancer immunotherapies generally aim to boost local immune responses in the tumor microenvironment, low systemic inflammation after systemic administration of the treatment may indeed enhance their tumor homing and improve the overall antitumor effect. These findings highlight the importance of selecting appropriate donor cells as therapeutic carriers in cell-based therapies for cancer treatment.Significance:Cells carrying drugs, virus, or other antitumor agents are commonly used for the treatment of cancer. This research shows that silent cells are excellent carriers for immunotherapies, improving tumor homing and enhancing the antitumor effect.

Several studies have evaluated the efficacy of using human oncolytic adenovirus (OAdv)–loaded mesenchymal stem cells (MSC) for cancer treatment. For example, we have described the antitumor efficacy of CELYVIR, autologous bone marrow–mesenchymal stem cells infected with the OAdv ICOVIR-5, for treatment of patients with neuroblastoma. Results from this clinical trial point out the role of the immune system in the clinical outcome. In this context, a better understanding of the immunophenotypic changes of human MSCs upon adenoviral infection and how these changes affect human autologous or allogeneic peripheral blood mononuclear cells (PBMC) could guide strategies to improve the antitumor efficacy of infected MSCs. In this work, we show how infection by an OAdv induces toll-like receptor 9 overexpression and activation of the NFĸB pathway in menstrual blood–derived MSCs, leading to a specific cytokine secretion profile. Moreover, a proinflammatory environment, mainly mediated by monocyte activation that leads to the activation of both T cells and natural killer cells (NK cell), is generated when OAdv-loaded MSCs are cocultured with allogeneic PBMCs. This combination of allogeneic PBMCs and OAdv-loaded MSCs enhances antitumor efficacy both in vitro and in vivo, an effect partially mediated by monocytes and NK cells. Altogether our results demonstrate not only the importance of the immune system for the OAdv-loaded MSCs antitumor efficacy, but in particular the benefits of using allogeneic MSCs for this therapy.

Supplementary Material and Methods

Supplementary Figure 1. Cytokine array; Supplementary Figure 2. Effect of TLR-9 knock-down on OAd-infected MenSCs properties.

Canine quality of life evaluation

Characterization of canine mesenchymal stem cells and their susceptibility to canine adenoviral infection and replication

Dogs with spontaneous tumors treated in veterinary hospitals offer an excellent opportunity for studying immunotherapies, including oncolytic viruses. Oncolytic viruses have advanced into the clinic as an intratumorally administered therapeutic; however, intravenous delivery has been hindered by neutralization in the blood. To circumvent this hurdle, mesenchymal stem cells have been used as a "Trojan horse." Here, we present the treatment of 27 canine patients with cancer with canine mesenchymal stem cells infected with ICOCAV17, a canine oncolytic adenovirus. No significant adverse effects were found. The response rate was 74%, with 14.8% showing complete responses, including total remissions of lung metastasis. We detected virus infection, stromal degeneration, and immune cell infiltration in tumor biopsies after 4 weeks of treatment. The increased presence of antiadenoviral antibodies in the peripheral blood of treated dogs did not appear to prevent the clinical benefit of this therapy. These data indicate that oncolytic viruses loaded in mesenchymal stem cells represent an effective cancer immunotherapy.Significance: The classical clinical limitations of antitumoral viroimmunotherapy can be overcome by use of mesenchymal stem cells.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/78/17/4891/F1.large.jpg. Cancer Res; 78(17); 4891–901. ©2018 AACR.

Supplementary Figure Legends

Sarcomas have been modeled in mice by the expression of specific fusion genes in mesenchymal stem cells (MSC), supporting the concept that MSCs might be the target initiating cell in sarcoma. In this study, we evaluated the potential oncogenic effects of p53 and/or retinoblastoma (Rb) deficiency in MSC transformation and sarcomagenesis. We derived wild-type, p53−/−, Rb−/−, and p53−/−Rb−/− MSC cultures and fully characterized their in vitro growth properties and in vivo tumorigenesis capabilities. In contrast with wild-type MSCs, Rb−/−, p53−/−, and p53−/−Rb−/− MSCs underwent in vitro transformation and showed severe alterations in culture homeostasis. More importantly, p53−/− and p53−/−Rb−/− MSCs, but not Rb−/− MSCs, were capable of tumor development in vivo after injection into immunodeficient mice. p53−/− or p53−/−Rb−/− MSCs originated leiomyosarcoma-like tumors, linking this type of smooth muscle sarcoma to p53 deficiency in fat tissue–derived MSCs. Sca1+ and Sca1 low/− cell populations isolated from ex vivo–established, transformed MSC lines from p53−/−Rb−/− tumors showed identical sarcomagenesis potential, with 100% tumor penetrance and identical latency, tumor weight, and histologic profile. Our findings define the differential roles of p53 and Rb in MSC transformation and offer proof-of-principle that MSCs could provide useful tools to dissect the sarcoma pathogenesis. Cancer Res; 70(10); 4185–94. ©2010 AACR.

Supplementary Figure 2 from Deficiency in p53 but not Retinoblastoma Induces the Transformation of Mesenchymal Stem Cells In vitro and Initiates Leiomyosarcoma In vivo

Supplementary Figure 1 from Deficiency in p53 but not Retinoblastoma Induces the Transformation of Mesenchymal Stem Cells In vitro and Initiates Leiomyosarcoma In vivo

Supplementary Figure 3 from Deficiency in p53 but not Retinoblastoma Induces the Transformation of Mesenchymal Stem Cells In vitro and Initiates Leiomyosarcoma In vivo

Factor de impacto: 5,987 Q1 There is increasing evidence about the use of oncolytic adenoviruses (Ads) as promising immunotherapy agents. We have previously demonstrated the clinical efficiency of mesenchymal stem cells (MSCs) infected with oncolytic Ads as an antitumoral immunotherapy (called Celyvir) in human and canine patients, using ICOVIR-5 or ICOCAV17 as human and canine oncolytic Ads, respectively. Considering the better clinical outcomes of canine patients, in this study we searched for differences in cellular responses of human and canine MSCs to Ad infection that may help understand the mechanisms leading to higher antitumor immune response. We found that infection of human and canine MSCs with ICOVIR-5 or ICOCAV17 did not activate the NF-κB pathway or the interferon regulatory factors IRF3 and IRF7. However, we observed differences in the profile of cytokines secretion, as infection of canine MSCs with ICOCAV17 resulted in lower secretion of several cytokines. Moreover, we showed that infection of human MSCs with ICOVIR-5 increased the phosphorylation of a number of proteins, including AKT and c-JUN. Finally, we demonstrated that differences in regulation of AKT and c-JUN in human and canine MSCs by ICOVIR-5 or ICOCAV17 are intrinsic to each virus. Our findings suggest that ICOCAV17 induces a more limited host response in canine MSCs, which may be related to a better clinical outcome. This result opens the possibility to develop new human oncolytic Ads with these specific properties. In addition, this improvement could be imitated by selecting specific human MSC on the basis of a limited host response after Ad infection. This study was funded by Instituto de Salud Carlos III (PI14CIII/00005 and PI17CIII/00013 grants), Consejería de Educación, Juventud y Deporte of Comunidad de Madrid (P2017/BMD-3692 grant), Fundación Oncohematología Infantil, AFANION, and Asociación Pablo Ugarte, whose support we gratefully acknowledge. Sí

Melancolía y espiritualidad han sido relacionadas en fechas tan tempranas como la Grecia clásica. Desde entonces, en cada época histórica, algunos de los autores más destacados en los campos de las humanidades, la filosofía, la medicina o las artes han realizado observaciones y comentarios acerca de la posible relación entre las personas con tendencias melancólicas y la inclinación espiritual. Para alcanzar el objetivo de esta investigación, que es hacer una revisión bibliográfica sobre la posible relación entre melancolía y espiritualidad, se han revisado documentos y obras originales sobre este tema de autores desde la Grecia clásica hasta el presente. De manera sistemática se encuentra una relación entre las personas melancólicas y la predisposición hacia la vida mística y espiritual, además de encontrar personas excepcionales, especialmente en el campo de las artes. Más concretamente, se señala que la angustia podría actuar como un mecanismo que impulsaría a la persona melancólica, desde el sufrimiento, a iniciar una profundización introspectiva y existencial, facilitando así el contacto con la vía mística y espiritual. Estas indagaciones previas deben ser complementadas y ampliadas con más investigaciones realizadas desde otros abordajes metodológicos que permitan corroborar las hipótesis planteadas. Asimismo, se recomienda tener en cuenta las limitaciones encontradas, como la falta de claridad conceptual acerca del significado de “melancolía” o la ausencia de metodologías cuantitativas. Melancholy and spirituality have been related as early as classical Greece. Since then, in every historical epoch, some of the most relevant authors in the fields of humanities, philosophy, medicine and the arts have made observations and comments about the possible relationship between melancholic people and spirituality tendency. For the purpose of this research, documents and original works about this topic have been reviewed since classical Grece to present. As a result of this review, a relationship between melancholic people and spirituality tendency is systematically found, also related to exceptional authors, especially in the arts. More specifically, anguish and suffering could act as mechanisms that would drive the melancholic person to initiate into introspection and existentialism, thus facilitating contact with the mystical and spiritual path. However, these preliminary inquiries should be complemented and expanded with more research carried out from other methodological approaches, allowing the corroboration of the hypothesis raised. Likewise, it is recommended to consider the limitations found, such as the lack of conceptual clarity about the meaning of "melancholy" or the absence of quantitative methodologies applied to this topic. Psicología y Ciencias de la Salud

Phubbing is defined as ignoring other individuals by using a mobile phone during a face-to-face conversation. The Phubbing Scale (PS) was developed to assess this practice. In this study, we analyze the psychometric properties of the 8-item version of the PS (PS-8) in the Portuguese population, providing validity evidence based on internal structure and on relationships with other variables, and examining item properties, reliability, and measurement invariance across gender. Participants were 391 Portuguese adults (132 men, 259 women) who completed a battery of questionnaires. Confirmatory factor analysis yielded satisfactory goodness-of-fit indices for the two-factor structure (communication disturbance and phone obsession), which was invariant across gender. Item homogeneity and reliability of factor scores (McDonald’s omega) were satisfactory. Validity evidence based on relationships with other variables was provided by positive associations with time spent on the Internet on weekdays and at the weekend, time spent on social networking sites, number of social networks used, Internet addiction, problematic mobile phone use, Facebook intrusion, fear of missing out, and depression. These associations show the addictive component of phubbing and its relationship with mental health. The PS-8 is a short and easy-to-administer scale with adequate psychometric properties for measuring phubbing in the Portuguese population.

espanolEl objetivo de este estudio es analizar la relacion, en cuidadores informales de personas con demencia, entre las fortalezas psicologicas y la salud mental, incluyendo depresion, ansiedad, estres, sobrecarga del cuidador y problemas de salud mental. Para analizar esta relacion se llevo a cabo diversos analisis de correlacion canonica, incluyendo en el primer conjunto las variables las fortalezas psicologicas, agrupadas por virtudes, y en el segundo las variables de salud psicologica. Los resultados sugieren la existencia de intercorrelaciones significativas entre estas variables. Aquellos cuidadores informales que tienden a mostrar puntuaciones mas elevadas en las fortalezas psicologicas correspondientes a las virtudes de Coraje, Humanidad, y Trascendencia tienden a mostrar menores puntuaciones en depresion, estres, sobrecarga del cuidador, y problemas de salud mental. En concreto, fueron significativas las relaciones con las fortalezas de valor, vitalidad, amor, inteligencia social, belleza, gratitud, esperanza y humor. Los hallazgos de este estudio sugieren que programas de intervencion basados en la promocion y desarrollo de estas fortalezas psicologicas podria mejorar la salud mental de los cuidadores. EnglishThe aim of this study was to analyze the relationship between character strengths and mental health in informal dementia caregivers. Variables included depression, anxiety, stress, caregiver burden, and mental health problems. We conducted a series of canonical-correlation analyses. The first set of variables comprised character strengths, classified into virtues, and the second set comprised the mental health variables. Results show significant intercorrelations between character strengths and informal caregivers’ mental health. Informal caregivers who tended to have higher scores in character strengths from the virtues of courage, humanity, and transcendence, also tended to have lower scores in depression, stress, caregiver burden, and mental health problems. Specifically, significant relationships were found between bravery, zest, love, social intelligence, appreciation of beauty, gratitude, hope, and humor. The findings from this study suggest that intervention programs based on the promotion and development of these character strengths might improve the psychological health of caregivers.

The aim was to analyze the psychometric properties of the Spanish version of the Gain in Alzheimer Care Instrument (GAIN), providing validity evidence based on its internal structure, reliability, item analysis, and relationships with other variables. A sample of 113 informal caregivers of people with dementia completed the GAIN, along with questionnaires assessing burden, general mental health, stress, anxiety, depression, and life satisfaction. Confirmatory factor analysis showed a single-factor structure with adequate fit indices. Reliability of GAIN scores was satisfactory, with McDonald’s omega equal to .91. Items yielded adequate homogeneity indices. Validity evidence based on relationships with other variables was provided by positive correlations between GAIN scores and life satisfaction, and negative correlations with burden, general mental health problems, stress, anxiety, and depression. All these correlations were statistically significant, and most of them were of moderate magnitude. The Spanish version of the GAIN has a single-factor structure and satisfactory psychometric properties. It is quick and easy to apply and given the association between GAIN scores and other variables, it may be used to provide information about a caregiver’s psychological health status. Funding for open access charge: Universidad de Málaga.

The relationship between caregiving and cognition remains unclear. We investigate this association comparing four cognitive tasks and exploring the role of potential explanatory pathways such as healthy behaviours (healthy caregiver hypothesis) and depression (stress process model).Respondents were from English Longitudinal Study of Ageing (ELSA) (Being a caregiver was positively associated with immediate and delayed recall, verbal fluency but not with serial 7. For immediate and delayed recall, these associations were partially attenuated when adjusting for health behaviours, and depression. For verbal fluency, associations were partially attenuated when adjusting for depression but fully attenuated when adjusting for health behaviours. No associations were found for serial 7.Our findings show that caregivers have higher level of memory and executive function compared to non-caregivers. For memory, we found that although health behaviours and depression can have a role in this association, they do not fully explain it. However, health behaviours seem to have a clear role in the association with executive function. Public health and policy do not need to target specifically cognitive function but other areas as the promotion of healthy behaviours and psychological adjustment such as preventing depression and promoting physical activity in caregivers.

Factor de impacto: 13,751 Q1 Osteosarcoma is the most common malignant solid tumor that affects bones, however, survival rates of patients with relapsed osteosarcoma have not improved in the last 30 years. Oncolytic virotherapy, which uses viruses designed to selectively replicate in cancer cells, has emerged as a promising treatment for solid tumors. Our group uses mesenchymal stem cells (MSCs) to transport oncolytic adenoviruses (OAds) to the tumor site, a therapeutic strategy called Celyvir. This treatment has been already applied in human patients, canine patients and different mouse models. In parallel, previous results have probed that administration of granulocyte-colony stimulating factor (G-CSF) increased immune infiltration in tumors. We then hypothesized that the mobilization of immune cells by G-CSF may increase the antitumor efficacy of Celyvir treatment by increasing the immune infiltration into the tumors. In this study, we use a murine version of Celyvir consisting in murine MSCs carrying the murine OAd dlE102-here called OAd-MSCs-in an immunocompetent model of osteosarcoma. We tested the antitumoral efficacy of the combination of OAd-MSCs plus G-CSF. Our results show that treatment with OAd-MSCs or the union of OAd-MSCs with G-CSF (Combination) significantly reduced tumor growth of osteosarcoma in vivo. Moreover, treated tumors presented higher tumor infiltration of immune cells-especially tumor-infiltrating lymphocytes-and reduced T cell exhaustion, which seems to be enhanced in tumors treated with the Combination. The comparison of our results to those obtained from a cohort of pediatric osteosarcoma patients showed that the virotherapy induces immunological changes similar to those observed in patients with good prognosis. The results open the possibility of using cellular virotherapy for the treatment of bone cancers. Indeed, its combination with G-CSF may be considered for the improvement of the therapy. This study was funded by the Instituto de Salud Carlos III of Spain (grant numbers PI14CIII/00005 and PI17CIII/00013), Consejería de Educación, Juventud y Deporte of Comunidad de Madrid (grant number P2017/BMD-3692), Fundación Oncohematología Infantil, Asociación Pablo Ugarte and AFANION, whose support we gratefully acknowledge. Sí

COVID-19 is a zoonotic disease caused by SARS-CoV-2. Infections of animals with SARS-CoV-2 have recently been reported, and an increase of severe lung pathologies in domestic dogs has also been detected by veterinarians in Spain. Therefore, further descriptions of the pathological processes in those animals that show symptoms similar to those described in humans affected by COVID-19 would be highly valuable. The potential for companion animals to contribute to the continued transmission and community spread of this known human-to-human disease is an urgent issue to be considered. Forty animals with pulmonary pathologies were studied by chest X-ray, ultrasound analysis, and computed tomography. Nasopharyngeal and rectal swabs were analyzed to detect canine pathogens, including SARS-CoV-2. An additional twenty healthy dogs living in SARS-CoV-2-positive households were included. Immunoglobulin detection by several immunoassays was performed. Our findings show that sick dogs presented severe alveolar or interstitial patterns with pulmonary opacity, parenchymal abnormalities, and bilateral lesions. The forty sick dogs were negative for SARS-CoV-2 but Mycoplasma spp. was detected in 26 of 33 dogs. Five healthy and one pathological dog presented IgG against SARS-CoV-2. Here we report that despite detecting dogs with α-SARS-CoV-2 IgG, we never obtained a positive RT-qPCR for SARS-SoV-2, not even in dogs with severe pulmonary disease; suggesting that even in the case of canine infection, transmission would be unlikely. Moreover, dogs living in COVID-19-positive households could have been more highly exposed to infection with SARS-CoV-2. Study funded by Fundación Universidad Alfonso X el Sabio (1.011.115 grant to A.J.P-B.; 1.011.101 to A.B-F.) and Comunidad de Madrid (COV20/01398 grant to A.J.P-B. and A.B-F.). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Sí

Neuroblastoma is a highly metastatic tumor that emerges from neural crest cell progenitors. Focal Adhesion Kinase (FAK) is a regulator of cell migration that binds to the receptor Neogenin-1 and is upregulated in neuroblastoma. Here, we show that Netrin-1 ligand binding to Neogenin-1 leads to FAK autophosphorylation and integrin β1 activation in a FAK dependent manner, thus promoting neuroblastoma cell migration. Moreover, Neogenin-1, which was detected in all tumor stages and was required for neuroblastoma cell migration, was found in a complex with integrin β1, FAK, and Netrin-1. Importantly, Neogenin-1 promoted neuroblastoma metastases in an immunodeficient mouse model. Taken together, these data show that Neogenin-1 is a metastasis-promoting protein that associates with FAK, activates integrin β1 and promotes neuroblastoma cell migration. This work was supported by the Comisión Nacional de Investigación Científica y Tecnológica [21130521]; Fondo Nacional de Desarrollo Científico y Tecnológico [1140697]; Fondo Nacional de Desarrollo Científico y Tecnológico [1180495]; Red Temática de Investigación Cooperativa en Cancer [RD12/0036/0027]; SAF [SAF2015-65175-R]; Red Temática de Investigación Cooperativa en Cancer [RD12/0036/0027]; PSG: Ministerio de Ciencia, Innovación y Universidades and FEDER funds (RTI2018-093596); JGC: Ministerio de Economía y Competitividad of Spain (PI17CIII/00013), Consejería de Educación, Juventud y Deporte, Comunidad de Madrid (P2017/BMD-3692), Fundación Oncohematología Infantil, AFANION, and Asociación Pablo Ugarte. Sí

WHAT IS KNOWN ON THE SUBJECT?: The role of informal caregiver can have both negative and positive consequences for a person's well-being. The main theoretical framework for explaining these consequences is the stress process model, which considers contextual variables, stressors and mediating/moderating factors. The latter are psychosocial factors such as coping strategies, personal mastery, social support or beliefs and values which may influence caregiver well-being. The perception of gains in caregiving has also been proposed as a mediating variable since it may act as a coping strategy. However, few studies have examined values and perceived gains as mediating variables with life satisfaction as the outcome. WHAT THE PAPER ADDS TO EXISTING KNOWLEDGE?: This study explores the role of character strengths and caregiver gains as mediators between stressors and life satisfaction in informal caregivers of persons with dementia. The results identify hope as a key character strength, its lack being one pathway through which stress may lead to low life satisfaction and low perceived gains from caregiving. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: Caregivers who experience a lack of hope may be less able to generate goals and be less motivated to achieve them. Our findings are relevant to gerontological nursing based on the Senses Framework as they confirm the importance of the senses of purpose and achievement. Nursing and care staff can play an active role in helping informal caregivers to meet their goals by promoting these two senses, thereby fostering a more positive caregiving experience. ABSTRACT: Introduction Being an informal caregiver can have both negative and positive consequences for well-being. Within the framework of the stress process model, few studies have examined values and perceived gains of caregiving as mediating variables of life satisfaction. Aim To explore the role of character strengths and perceived gains as mediators in the association between life satisfaction and primary and secondary stressors in informal caregivers of persons with dementia. Method Participants were 112 informal caregivers. Hierarchical regression, correlation and mediation analyses were performed. Results Lower life satisfaction was associated with being female, unmarried, caring for someone with greater cognitive impairment, a higher level of stress, having restricted leisure time and perceiving financial difficulties. Hope mediated the associations between perceived stress and both life satisfaction and perceived gains of caregiving. Discussion Hope is a key strength and its lack is one pathway through which stress may cause low satisfaction and low perceived gains from caregiving. Implications for practice Without hope, it is difficult for caregivers to generate goals and be motivated to achieve them. Nursing and care staff should aim to promote a sense of purpose and achievement among informal caregivers so as to foster a more positive caring experience.

Oncolytic virotherapy uses viruses designed to selectively replicate in cancer cells. An alternative to intratumoral administration is to use mesenchymal stem cells (MSCs) to transport the oncolytic viruses to the tumor site. Following this strategy, our group has already applied this treatment to children and adults in a human clinical trial and a veterinary trial, with good clinical responses and excellent safety profiles. However, the development of immunocompetent cancer mouse models is still necessary for the study and improvement of oncolytic viroimmunotherapies. Here we have studied the antitumor efficacy, immune response, and mechanism of action of a complete murine version of our cellular virotherapy in mouse models of renal adenocarcinoma and melanoma. We used mouse MSCs infected with the mouse oncolytic adenovirus dlE102 (OAd-MSCs). In both models, treatment with OAd-MSCs significantly reduced tumor volumes by 50% and induced a pro-inflammatory tumor microenvironment. Furthermore, treated mice harboring renal adenocarcinoma and melanoma tumors presented increased infiltration of tumor-associated macrophages (TAMs), natural killer cells, and tumor-infiltrating lymphocytes (TILs). Treated mice also presented lower percentage of TILs expressing programmed cell death protein 1 (PD-1)&mdash, the major regulator of T cell exhaustion. In conclusion, treatment with OAd-MSCs significantly reduced tumor volume and induced changes in tumor-infiltrating populations of melanoma and renal cancer.

Oncolytic virotherapy uses viruses designed to selectively replicate in cancer cells. An alternative to intratumoral administration is to use mesenchymal stem cells (MSCs) to transport the oncolytic viruses to the tumor site. Following this strategy, our group has already applied this treatment to children and adults in a human clinical trial and a veterinary trial, with good clinical responses and excellent safety profiles. However, the development of immunocompetent cancer mouse models is still necessary for the study and improvement of oncolytic viroimmunotherapies. Here we have studied the antitumor efficacy, immune response, and mechanism of action of a complete murine version of our cellular virotherapy in mouse models of renal adenocarcinoma and melanoma. We used mouse MSCs infected with the mouse oncolytic adenovirus dlE102 (OAd-MSCs). In both models, treatment with OAd-MSCs significantly reduced tumor volumes by 50% and induced a pro-inflammatory tumor microenvironment. Furthermore, treated mice harboring renal adenocarcinoma and melanoma tumors presented increased infiltration of tumor-associated macrophages (TAMs), natural killer cells, and tumor-infiltrating lymphocytes (TILs). Treated mice also presented lower percentage of TILs expressing programmed cell death protein 1 (PD-1)—the major regulator of T cell exhaustion. In conclusion, treatment with OAd-MSCs significantly reduced tumor volume and induced changes in tumor-infiltrating populations of melanoma and renal cancer.

Background: Stemness in sarcomas is coordinated by the expression of pluripotency factors, like SOX2, in cancer stem cell (CSC) subpopulations. The role of SOX2 in tumor initiation and progression has been well characterized in osteosarcoma. However, the pro-tumorigenic features of SOX2 have been scarcely investigated in other sarcoma subtypes. Methods: shRNA and cDNA lentiviral constructions were used to deplete and overexpress SOX2 in a model of undifferentiated pleomorphic sarcoma (UPS). In addition, we introduced a reporter system (SORE6) which allows to detect and isolate viable cells expressing SOX2 and/or OCT4 in the UPS model and patient-derived chondrosarcoma lines. Functional CSC characterization included tumorsphere formation, in vivo xenograft growth assays, and pharmacologic testing of the effects of doxorubicin, placlitaxel, trabectedin or the mithramycin analogue EC8042. Immunohistochemical analysis of a cohort of 88 formalin-fixed and paraffin-embedded sarcoma samples was performed to correlate SOX2 expression with clinical parameters. Findings: SOX2 depletion dramatically reduced the ability of sarcoma cells to form tumorspheres and to initiate tumor growth in vivo. Conversely, SOX2 overexpression resulted in increased in vivo tumorigenicity. In sarcoma patients, SOX2 expression was associated to advanced disease stages, aggressive phenotypes and lower survival. Finally, SORE6+ cells were significantly more tumorigenic than the SORE6- population and EC-8042 effectively targeted SORE6+ cells in vitro and in vivo. Interpretation: SOX2 is a pro-tumorigenic factor with prognostic potential in sarcoma. Moreover, SORE6 transcriptional activity is a bona fide CSC marker in sarcoma and constitutes an excellent biomarker for evaluating the efficacy of anti-tumor treatments on CSC subpopulations. Funding Statement: This work was supported by the Agencia Estatal de Investigacion (AEI) [MINECO/Fondo Europeo de Desarrollo Regional (FEDER) (SAF-2016-75286-R to R.R.), ISC III/FEDER (Miguel Servet Program CPII16/00049 to R.R., Sara Borrell Program CD16/00103 to S.T.M. and PI16/00280 and PI19/00560 to J.M.G-P) and Consorcio CIBERONC CB16/12/00390)] and the Plan de Ciencia Tecnologia e Innovacion del Principado de Asturias/FEDER (IDI/2018/155) to J.P.R. PharmaMar and EntreChem also provided support. Finally, the authors acknowledge the Principado de Asturias BioBank (PT17/0015/0023), financed jointly by Servicio de Salud del Principado de Asturias, Instituto de Salud Carlos III and Fundacion Bancaria Cajastur and integrated in the Spanish National Biobanks Network, for its collaboration. Declaration of Interests: The authors declare they have no competing interests. Ethics Approval Statement: All experimental protocols have been performed in accordance with institutional review board guidelines and were approved by the Institutional Ethics Committee of the Principado de Asturias. All samples from human origin were obtained upon signed informed consent. All experimental protocols were carried out in accordance with the institutional guidelines of the University of Oviedo and were approved by the Animal Research Ethical Committee of the University of Oviedo prior to the study.

Factor de impacto: 6,968 Q1 Oncolytic virotherapy uses oncolytic viruses that selectively replicate in cancer cells. The use of cellular vehicles with migration ability to tumors has been considered to increase their delivery to target sites. Following this approach, the antitumor efficacy of the treatment Celyvir (mesenchymal stem cells infected with the oncolytic adenovirus ICOVIR-5) has been demonstrated in patients with neuroblastoma. However, the better efficacy of syngeneic or allogeneic mesenchymal stem cells as cell carriers and the specific role of the immune system in this therapy are still unknown. In this study we use our virotherapy Celyvir with syngeneic and allogeneic mouse mesenchymal stem cells to determine their antitumor efficacy in a C57BL/6 murine adenocarcinoma model. Adoptive transfer of splenocytes from treated mice to new tumor-bearing mice followed by a secondary adoptive transfer to a third group was performed. Similar reduction of tumor growth and systemic activation of the innate and adaptive immune system was observed in groups treated with syngeneic or allogeneic mesenchymal stem cells loaded with ICOVIR-5. Moreover, a different pattern of infiltration was observed by immunofluorescence in Celyvir-treated groups. While non-treated tumors presented higher density of infiltrating immune cells in the periphery of the tumor, both syngeneic and allogeneic Celyvir-treated groups presented higher infiltration of CD45+ cells in the core of the tumor. Therefore, these results suggest that syngeneic and allogeneic Celyvir induce systemic activation of the immune system, similar antitumor effect and a higher intratumoral infiltration of leukocytes. Funding for this research was provided by: Consejería de Educación, Juventud y Deporte, Comunidad de Madrid (P2010/BMD-2420) Asociación Pablo Ugarte Fondo de Investigaciones Sanitarias (PI17/00013, PI14CIII/00005) Fundación Oncohematología Infantil AFANION Sí

Keratoconjunctivitis sicca (KCS) is characterized by ocular discomfort, conjunctival hyperaemia, and corneal scarring, causing reduced aqueous tear production that can be measured using the standard Schirmer tear test (STT). Canine adipose tissue-derived MSCs (cATMSCs) have been proposed as treatment due to their anti-inflammatory effect, by releasing cytokines and immunomodulatory soluble factors. The aim of this study was to evaluate the effect of the systemic administration of cATMSCs on tear production in dogs with immune-mediated KCS, compared to classical Cyclosporine A (CsA) treatment. Twenty-eight client-owned dogs with spontaneous KCS were allocated in the experimental group (n = 14, treated with systemic cATMSCs or control group (n = 14, treated with CsA). SST values increased significantly at days 15 (p = 0.002), 45 (p = 0.042) and 180 (p = 0.005) with no observed side-effects in the experimental group. Eyes with an initial STT value of 11-14 mm/min maintained significant improvement at day 180, needing only artificial tears as treatment. Eyes with an initial STT value

Background: COVID-19 is a zoonotic disease originated by SARS-CoV-2. Infection of animals with SARS-CoV-2 are being reported during last months, and also an increase of severe lung pathologies in domestic dogs has been detected by veterinarians in Spain. Therefore it is necessary to describe the pathological processes in those animals that show symptoms similar to those described in humans affected by COVID-19. The potential for companion animals contributing to the continued human-to-human disease, infectivity, and community spread is an urgent issue to be considered. Methods: Forty animals with pulmonary pathologies were studied by chest X-ray, ultrasound study, and computed tomography. Nasopharyngeal and rectal swab were analyzed to detect canine pathogens, including SARS-CoV-2. Twenty healthy dogs living in SARS-CoV-2 positive households were included. Immunoglobulin detection by different immunoassays was performed. Findings: Sick dogs presented severe alveolar or interstitial pattern, with pulmonary opacity, parenchymal abnormalities, and bilateral lesions. Forty dogs were negative for SARS-CoV-2 but Mycoplasma spp. was detected in 26 of 33 dogs. Five healthy and one pathological dog presented IgG against SARS-CoV-2. Interpretation: Despite detecting dogs with IgG α-SARS-CoV-2, we never obtained a positive RT-qPCR, not even in dogs with severe pulmonary disease; suggesting that even in the case of a canine infection transmission would be unlikely. Moreover, dogs living in COVID-19 positive households could have been more exposed to be infected during outbreaks. Funding: Study funded by Fundacion Universidad Alfonso X el Sabio, 1.011.115 grant to A.J.P-B.; 1.011.101 grant to A.B-F. Declaration of Interests: The authors declare no potential conflicts of interest. Ethics Approval Statement: The study was approved by the Ethical Committee of the Faculty of Health Sciences, Alfonso X el Sabio University and all dog owners gave written informed consent.

Oncolytic immunotherapy with competent viruses is an emerging approach in cancer treatment. The clinical safety of many types of oncolytic viruses (OVs) has been demonstrated. However, there is a lack of information about viral biodistribution in patients. The available data about oncolytic adenovirus biodistribution in human subjects treated intravenously consists of virus detection in body fluids, a few tumor biopsies, and a single report of patient necropsy samples. There is no information about adenoviral biodistribution in patients treated intravenously with cellular vehicles carrying an oncolytic adenovirus. We previously published reports regarding the efficacy and clinical safety of infusing mesenchymal stem cells (MSCs) infected with an OV in human and canine patients. In this study, we performed necropsies on 12 canine patients treated with dCelyvir, canine MSCs infected with ICOCAV17, a canine oncolytic adenovirus. The prevalence of microscopic lesions, especially chronic inflammatory responses in different organs, was higher than expected. Concomitantly, we found a positive immunoreaction to ICOCAV17 in analyzed samples. These findings support a possible role of the virus in development of histopathological alterations and ongoing systemic viral replication of ICOCAV17 in the period after therapy administration., Graphical Abstract, Perisé-Barrios and colleagues performed necropsies on canine patients treated with oncolytic immunotherapy. They report a higher inflammatory response and detected an oncolytic virus in different tissues. These findings support a possible role of the virus in histopathological alterations and ongoing systemic viral replication after therapy administration.

We present here the results of a first-in-human, first-in-child trial for patients with relapsed/refractory solid tumors using Celyvir, an advanced therapy medicine that combines autologous mesenchymal stem cells (MSCs) carrying an oncolytic adenovirus. Celyvir was manufactured from a bone marrow aspirate and then given intravenously. Patients received weekly infusions for 6 weeks at a dose of 2 × 106 cells/kg (children) or 0.5-1 × 106 cells/kg (adults), 2 × 104 viral particles per cell. Fifteen pediatric and 19 adult patients were recruited, but 18 were screen failures, mainly because rapid disease progression before Celyvir was available. No grade 2-5 toxicities were reported. Adenoviral replication detected by PCR was found in all but 2 pediatric patient and in none of the adult ones. Absolute numbers of circulating leukocytes suffered minor changes along therapy, but some subsets showed differences comparing the pediatric versus the adult cohorts. Two patients with neuroblastoma showed disease stabilization, and one of them continued on treatment for up to 6 additional weeks. Celyvir, the combination of MSCs and oncolytic adenovirus, is safe and warrants further evaluation in a phase 2 setting. The use of MSCs may be a strategy to increase the amount of oncolytic virus administered to patients, minimizing toxicities and avoiding direct tumor injections. The trial was sponsored by Fundación de Investigacion Biomedica del Hospital Nino Jesus (EudraCT 2008-000364-16; NCT01844661). This work was funded by grants EC11/061, EC08/00094, and EC07/90591 from Instituto de Salud Carlos III and Fondos FEDER. M.R is supported by Asociación Pablo Ugarte, Asociación NEN, and Fundación Neuroblastoma. Sí