Linfocitos intraepiteliales y células dendríticas: Distribución y utilidad en el diagnóstico y en la modulación de la respuesta inmunitaria intestinal.

El intestino representa el órgano inmunitario más grande y complejo que existe, sometido a una estimulación constante durante toda la vida tanto por antígenos de la dieta y flora bacteriana comensal, como por microorganismos patógenos oportunistas. Debido a ésto, la mucosa intestinal requiere una respuesta rápida aunque inespecífica para mantener la homeostasis intestinal y proteger al organismo de la entrada de patógenos en caso de que sea necesario. Esta respuesta depende de la inmunidad innata que se complementa con los mecanismos de tolerancia oral. Las principales poblaciones del sistema inmunitario encargadas de mantener la homeostasis son los linfocitos intraepiteliales (LIE) y las poblaciones de la lamina propia (LP). Entre estas últimas destacan las células dendríticas (CD) gracias a que son las células presentadoras de antígeno profesionales más potentes que existen. Los LIE son una población heterogénea y peculiar, compuesta sobre todo por células Tab, Tgd y células natural killer (NK), que se encuentran intercalados entre los enterocitos. Su singularidad, en cuanto a su ubicación, sus vías de desarrollo, su especificidad para reconocer antígenos propios y potencialmente patogénicos, y su especialización funcional con características entre la inmunidad innata y adaptativa, permite a estas células efectoras ser la primera barrera defensiva en un órgano con una gran carga antigénica, además de proteger la integridad de la barrera mucosa. Sin embargo, su estado activado en ambientes pro-inflamatorios sugiere que estas poblaciones pueden contribuir a iniciar y/o exacerbar una respuesta patológica, como ocurre en la enfermedad inflamatoria intestinal (EII) y la enfermedad celíaca (EC). Nuestro laboratorio de investigación se ha dedicado a lo largo de su trayectoria al estudio de los diferentes mecanismos inmunopatogénicos responsables de estas patologías intestinales, centrándonos en este caso en el papel que pueden tener los LIE en el desarrollo de las enfermedades intestinales inflamatorias.Departamento de Pediatría e Inmunología, Obstetricía y Ginecología, Psiquiatría e Historia de la Medicin

Photocurable Thiol–yne Alginate Hydrogels for Regenerative Medicine Purposes

Every year millions of people worldwide undergo surgical interventions, with the occur- rence of mild or severe post-treatment consequences meaning that rehabilitation plays a key role in modern medicine. Considering the cases of burns and plastic surgery, the pressing need for new materials that can be used for wound patches or body fillers and are able to sustain tissue regeneration and promote cell adhesion and proliferation is clear. The challenges facing next-generation implant materials also include the need for improved structural properties for cellular organization and morphogenic guidance together with optimal mechanical, rheological, and topographical behavior. Herein, we propose for the first time a sodium alginate hydrogel obtained by a thiol–yne reaction, easily synthesized using carbodiimide chemistry in a two-step reaction. The hydrogels were formed in all cases within a few minutes of light irradiation, showing good self-standing properties under solicitation. The mechanical, rheological, topographical, and swelling properties of the gels were also tested and reported. Lastly, no cytotoxicity was detected among the hydrogels. Soluble extracts in cul- ture media allowed cell proliferation, and no differences between samples were detected in terms of metabolic activity and DNA content. These results suggest the potential use of these cytocompatible hydrogels in tissue engineering and regenerative medicine.Laura Montalvillo-Jiménez, Paula Bosch, Raquel Cue-López, and Enrique Martínez- Campos acknowledge the Spanish National Research Council—CSIC Interdisciplinary Thematic Platform Salud Global+ (PTI-SALUDGLOBAL+) for providing financial support.Peer reviewe

Autoimmune responses in oncology: Causes and significance

© 2021 by the authors.Specific anti-tumor immune responses have proven to be pivotal in shaping tumorigenesis and tumor progression in solid cancers. These responses can also be of an autoimmune nature, and autoantibodies can sometimes be present even before the onset of clinically overt disease. Autoantibodies can be generated due to mutated gene products, aberrant expression and post-transcriptional modification of proteins, a pro-immunogenic milieu, anti-cancer treatments, cross-reactivity of tumor-specific lymphocytes, epitope spreading, and microbiota-related and genetic factors. Understanding these responses has implications for both basic and clinical immunology. Autoantibodies in solid cancers can be used for early detection of cancer as well as for biomarkers of prognosis and treatment response. High-throughput techniques such as protein microarrays make parallel detection of multiple autoantibodies for increased specificity and sensitivity feasible, affordable, and quick. Cancer immunotherapy has revolutionized cancer treatments and has made a considerable impact on reducing cancer-associated morbidity and mortality. However, immunotherapeutic interventions such as immune checkpoint inhibition can induce immune-related toxicities, which can even be life-threatening. Uncovering the reasons for treatment-induced autoimmunity can lead to fine-tuning of cancer immunotherapy approaches to evade toxic events while inducing an effective anti-tumor immune response.We gratefully acknowledge financial support from the Spanish Health Institute Carlos III (ISCIII) for grants FIS PI14/01538, FIS PI17/01930, and CB16/12/00400. We also acknowledge Fondos FEDER (EU), Junta Castilla-León (COVID-19 grant COV20EDU/00187), and Fundación Solórzano FS/38-2017. The Proteomics Unit belongs to ProteoRed, PRB3-ISCIII, supported by grant PT17/0019/0023 of the PE I + D + I 2017–2020 and funded by ISCIII and FEDER. A. Landeira-Viñuela is supported by the VIII Centenario-USAL PhD Program. P. Juanes-Velasco is supported by the JCYL PhD Program ‘JCYL Nos Impulsa’ and scholarship JCYL-EDU/601/2020

Human colon-derived soluble factors modulate gut microbiota composition

This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY).-- et al.The commensal microbiota modulates immunological and metabolic aspects of the intestinal mucosa contributing to development of human gut diseases including inflammatory bowel disease. The host/microbiota interaction often referred to as a crosstalk, mainly focuses on the effect of the microbiota on the host neglecting effects that the host could elicit on the commensals. Colonic microenvironments from three human healthy controls (obtained from the proximal and distal colon, both in resting conditions and after immune - IL-15-and microbiota - LPS-in vitro challenges) were used to condition a stable fecal population. Subsequent 16S rRNA gene-based analyses were performed to study the effect induced by the host on the microbiota composition and function. Non-supervised principal component analysis (PCA) showed that all microbiotas, which had been conditioned with colonic microenvironments clustered together in terms of relative microbial composition, suggesting that soluble factors were modulating a stable fecal population independently from the treatment or the origin. Our findings confirmed that the host intestinal microenvironment has the capacity to modulate the gut microbiota composition via yet unidentified soluble factors. These findings indicate that an appropriate understanding of the factors of the host mucosal microenvironment affecting microbiota composition and function could improve therapeutic manipulation of the microbiota composition.BS and AH were recipients of a Ramón y Cajal postdoctoral contract and a FPI grant, respectively, from the Spanish Ministry of Economy and Competitiveness. The authors gratefully acknowledge the support of the Biotechnology and Biological Sciences Research Council (BBSRC). This research was funded by the BBSRC Institute Strategic Programme for Gut Health and Food Safety BB/J004529/1. This research was also funded by Grants AGL2010-14952 and AGL2013-44039-R from the Spanish “Plan Estatal de I + D + i,” and by Grant EM2014/046 from the “Plan galego de investigación, innovación e crecemento 2011-2015.”Peer Reviewe

Systematic evaluation of plasma signaling cascades by functional proteomics approaches: SARS-CoV-2 infection as model

Purpose Acute phase reactants (APRs) play a critical role in inflammation. The difference in their physiological functions or the different dynamic ranges of these proteins in plasma makes it difficult to detect them simultaneously and to use several of these proteins as a tool in clinical practice. Experimental Design A novel multiplex assay has been designed and optimized to carry out a high-throughput and simultaneous screening of APRs, allowing the detection of each of them at the same time and in their corresponding dynamic range. Results Using Sars-CoV-2 infection as a model, it has been possible to profile different patterns of acute phase proteins that vary significantly between healthy and infected patients. In addition, severity profiles (acute respiratory distress syndrome and sepsis) have been established. Conclusions and Clinical Relevance Differential profiles in acute phase proteins can serve as a diagnostic and prognostic tool, among patient stratification. The design of this new platform for their simultaneous detection paves the way for them to be more extensive use in clinical practice.We gratefully acknowledge financial support from the Spanish Health Institute Carlos III (ISCIII) for the grants: FIS PI18/00682, FIS PI21/01545 and CB16/12/00400. We also acknowledge Fondos FEDER (EU) and Junta Castilla-León (COVID-19 grant COV20EDU/00187). The Proteomics Unit belongs to ProteoRed, PRB3-ISCIII, supported by grant PT17/0019/0023, of the PE I+D+I 2017–2020, funded by ISCIII and FEDER. This research work was funded by the European Commission -NextGenerationEU, through CSIC's Global Health Platform (PTI Salud Global). This research work was performed in the framework of the Nanomedicine CSIC HUB (ref. 202180E048). AL-V is supported by VIII Centenario-USAL PhD Program. PJ-V is supported by JCYL PhD Program “Nos Impulsa-JCYL” and scholarship JCYL-EDU/601/2020.Peer reviewe

Tracking the antibody immunome in sporadic colorectal cancer by using antigen self-assembled protein arrays

© 2021 by the authors.Sporadic Colorectal Cancer (sCRC) is the third leading cause of cancer death in the Western world, and the sCRC patients presenting with synchronic metastasis have the poorest prognosis. Genetic alterations accumulated in sCRC tumor cells translate into mutated proteins and/or abnormal protein expression levels, which contribute to the development of sCRC. Then, the tumor-associated proteins (TAAs) might induce the production of auto-antibodies (aAb) via humoral immune response. Here, Nucleic Acid Programmable Protein Arrays (NAPPArray) are employed to identify aAb in plasma samples from a set of 50 sCRC patients compared to seven healthy donors. Our goal was to establish a systematic workflow based on NAPPArray to define differential aAb profiles between healthy individuals and sCRC patients as well as between non-metastatic (n = 38) and metastatic (n = 12) sCRC, in order to gain insight into the role of the humoral immune system in controlling the development and progression of sCRC. Our results showed aAb profile based on 141 TAA including TAAs associated with biological cellular processes altered in genesis and progress of sCRC (e.g., FSCN1, VTI2 and RPS28) that discriminated healthy donors vs. sCRC patients. In addition, the potential capacity of discrimination (between non-metastatic vs. metastatic sCRC) of 7 TAAs (USP5, ML4, MARCKSL1, CKMT1B, HMOX2, VTI2, TP53) have been analyzed individually in an independent cohort of sCRC patients, where two of them (VTI2 and TP53) were validated (AUC ~75%). In turn, these findings provided novel insights into the immunome of sCRC, in combination with transcriptomics profiles and protein antigenicity characterizations, wich might lead to the identification of novel sCRC biomarkers that might be of clinical utility for early diagnosis of the tumor. These results explore the immunomic analysis as potent source for biomarkers with diagnostic and prognostic value in CRC. Additional prospective studies in larger series of patients are required to confirm the clinical utility of these novel sCRC immunomic biomarkers.We gratefully acknowledge financial support from the Spanish Health Institute Carlos III (ISCIII) for the grants: FIS PI14/01538, FIS PI17/01930 and CB16/12/00400. We also acknowledge Fondos FEDER (EU) “Una manera de hacer Europa” and Junta Castilla-León (COVID19 grant COV20EDU/00187). Fundación Solórzano FS/38-2017. The Proteomics Unit belongs to ProteoRed, PRB3-ISCIII, supported by grant PT17/0019/0023, of the PE I + D + I 2017-2020, funded by ISCIII and FEDER. CNPq-National Council for Scientific and Technological Development (Brazil) (306258/2019-6) and FAPERJ-Foundation for Research Support of Rio de Janeiro State for the financial support (E-26/201.670/2017 and 210.379/2018). M. González-González is supported by MINECOPTA2019-017870-I.A. Landeira-Viñuela is supported by VIII Centenario-USAL PhD Program. P.J.-V. is supported by JCYL PhD Program and scholarship JCYL-EDU/601/2020. P.D. and E.B. are supported by a JCYL-EDU/346/2013 Ph.D. scholarship

Chemokine (C-C Motif) Receptor 2 Mediates Dendritic Cell Recruitment to the Human Colon but Is Not Responsible for Differences Observed in Dendritic Cell Subsets, Phenotype, and Function Between the Proximal and Distal Colon.

BACKGROUND & AIMS: Most knowledge about gastrointestinal (GI)-tract dendritic cells (DC) relies on murine studies where CD103+ DC specialize in generating immune tolerance with the functionality of CD11b+/- subsets being unclear. Information about human GI-DC is scarce, especially regarding regional specifications. Here, we characterized human DC properties throughout the human colon. METHODS: Paired proximal (right/ascending) and distal (left/descending) human colonic biopsies from 95 healthy subjects were taken; DC were assessed by flow cytometry and microbiota composition assessed by 16S rRNA gene sequencing. RESULTS: Colonic DC identified were myeloid (mDC, CD11c+CD123-) and further divided based on CD103 and SIRPα (human analog of murine CD11b) expression. CD103-SIRPα+ DC were the major population and with CD103+SIRPα+ DC were CD1c+ILT3+CCR2+ (although CCR2 was not expressed on all CD103+SIRPα+ DC). CD103+SIRPα- DC constituted a minor subset that were CD141+ILT3-CCR2-. Proximal colon samples had higher total DC counts and fewer CD103+SIRPα+ cells. Proximal colon DC were more mature than distal DC with higher stimulatory capacity for CD4+CD45RA+ T-cells. However, DC and DC-invoked T-cell expression of mucosal homing markers (β7, CCR9) was lower for proximal DC. CCR2 was expressed on circulating CD1c+, but not CD141+ mDC, and mediated DC recruitment by colonic culture supernatants in transwell assays. Proximal colon DC produced higher levels of cytokines. Mucosal microbiota profiling showed a lower microbiota load in the proximal colon, but with no differences in microbiota composition between compartments. CONCLUSIONS: Proximal colonic DC subsets differ from those in distal colon and are more mature. Targeted immunotherapy using DC in T-cell mediated GI tract inflammation may therefore need to reflect this immune compartmentalization

Seminarios multimedia de implanto-prótesis y patología oclusal

Memoria ID-0116. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2014-2015

Creación de una web del Grupo de Investigación: avances en Salud Oral

Memoria ID-0135. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2015-2016

Innate lymphoid cells and natural killer T cells in the gastrointestinal tract immune system

The gastrointestinal tract is equipped with a highly specialized intrinsic immune system. However, the intestine is exposed to a high antigenic burden that requires a fast, nonspecific response -so-called innate immunity- to maintain homeostasis and protect the body from incoming pathogens. In the last decade multiple studies helped to unravel the particular developmental requirements and specific functions of the cells that play a role in innate immunity. In this review we shall focus on innate lymphoid cells, a newly discovered, heterogeneous set of cells that derive from an Id2-dependent lymphoid progenitor cell population. These cells have been categorized on the basis of the pattern of cytokines that they secrete, and the transcription factors that regulate their development and functions. Innate lymphoid cells play a role in the early response to pathogens, the anatomical contention of the commensal flora, and the maintenance of epithelial integrity. Amongst the various innate lymphoid cells we shall lay emphasis on a subpopulation with several peculiarities, namely that of natural killer T cells, a subset of T lymphocytes that express both T-cell and NK-cell receptors. The most numerous fraction of the NKT population are the so-called invariant NKT or iNKT cells. These iNKT cells have an invariant TCR and recognize the glycolipidic structures presented by the CD1d molecule, a homolog of class-I MHC molecules. Following activation they rapidly acquire cytotoxic activity and secrete both Th1 and Th2 cytokines, including IL-17. While their specific role is not yet established, iNKT cells take part in a great variety of intestinal immune responses ranging from oral tolerance to involvement in a number of gastrointestinal conditions