Nanosized UCMSC-derived extracellular vesicles but not conditioned medium exclusively inhibit the inflammatory response of stimulated T cells: implications for nanomedicine

Altres ajuts: La Marató TV3 (201502 i 201516). This work has been developed in the context of AdvanceCat with the support of ACCIÓ (Catalonia Trade & Investment; Generalitat de Catalunya) under the Catalonian ERDF operational program (European Regional Development Fund) 2014-2020. FEB is sponsored by the "Researchers Stabilization Program" from the Spanish "Sistema Nacional de Salud" (SNS-ISCIII) and "Direcció d'Estratègia i Coordinació" Catalan Health Department (CES07/015).Undesired immune responses have drastically hampered outcomes after allogeneic organ transplantation and cell therapy, and also lead to inflammatory diseases and autoimmunity. Umbilical cord mesenchymal stem cells (UCMSCs) have powerful regenerative and immunomodulatory potential, and their secreted extracellular vesicles (EVs) are envisaged as a promising natural source of nanoparticles to increase outcomes in organ transplantation and control inflammatory diseases. However, poor EV preparations containing highly-abundant soluble proteins may mask genuine vesicular-associated functions and provide misleading data. Here, we used Size-Exclusion Chromatography (SEC) to successfully isolate EVs from UCMSCs-conditioned medium. These vesicles were defined as positive for CD9, CD63, CD73 and CD90, and their size and morphology characterized by NTA and cryo-EM. Their immunomodulatory potential was determined in polyclonal T cell proliferation assays, analysis of cytokine profiles and in the skewing of monocyte polarization. In sharp contrast to the non-EV containing fractions, to the complete conditioned medium and to ultracentrifuged pellet, SEC-purified EVs from UCMSCs inhibited T cell proliferation, resembling the effect of parental UCMSCs. Moreover, while SEC-EVs did not induce cytokine response, the non-EV fractions, conditioned medium and ultracentrifuged pellet promoted the secretion of pro-inflammatory cytokines by polyclonally stimulated T cells and supported Th17 polarization. In contrast, EVs did not induce monocyte polarization, but the non-EV fraction induced CD163 and CD206 expression and TNF-α production in monocytes. These findings increase the growing evidence confirming that EVs are an active component of MSC's paracrine immunosuppressive function and affirm their potential for therapeutics in nanomedicine. In addition, our results highlight the importance of well-purified and defined preparations of MSC-derived EVs to achieve the immunosuppressive effect

Influència del microquimerisme hematopoètic en l'establiment del rebuig en transplantaments d'òrgans sòlids

[spa] La presència de cèl·lules del donant en el receptor després del trasplantament d'un òrgan sòlid ha estat objecte de controvèrsia des de mitjans del segle XX. Tot va començar amb el descobriment de l'acceptació de trasplantaments de pell entre bessons bovins bivitel·lins amb anastomosis vasculars. L'evolució marcada de les tècniques de trasplantament i la disminució del rebuig amb l'aparició de la immunosupressió han permès perllongar la vida de l'empelt i augmentar el nombre de trasplantaments amb èxit. No obstant encara subsisteix un índex massa elevat de rebuig agut que compromet la supervivència de l'empelt a mig-llarg termini. Arribats a aquest punt, algunes experimentacions han suggerit que el microquimerisme podria ser una opció per a disminuir la incidència d'aquest tipus de rebuig en els pacients trasplantats. Els resultats descrits en aquesta tesi permeten en primer lloc demostrar l'existència d'aquest microquimerisme a nivell molecular en els pacients trasplantats de ronyó, de cor o de fetge. En segon lloc, es va correlacionar la presència de microquimerisme al segon mes post-trasplantament amb una més baixa incidència de rebuig agut en pacients trasplantats de ronyó i una tendència similar per als pacients amb trasplantament de cor. Tenint en compte l'absència d'episodis de rebuig a 4 anys en els pacients amb microquimerisme, aquest podria ser considerat com a factor precoç de pronòstic del rebuig agut a mig termini, suposant així la classificació dels pacients en grups de risc de rebuig en funció de l'absència o la presència de microquimerisme als dos mesos.[eng] The presence of a few circulating donor cells in recipient's blood was first thought to be only an epiphenomenon of solid organ transplantation, also called microchimerism, but several authors have suggested that these circulating cells may contribute to tolerance induction. This study aims to assess the rate of microchimerism after kidney transplantation and determine its influence on acute rejection in a 4-year follow-up. A total of 84 single-kidney recipients were included for microchimerism detection and quantification 2, 6, 12, and 18 months after transplantation by specific detection of non-shared STR, VNTR, human leukocyte antigen-A, -B, -DRB1, and SRY alleles. Kinetic establishment of microchimerism was monitored in a double kidney transplanted recipient for 150 min after declamping and after 7 days. Microchimerism was detected in 56.2% of kidney recipients 2 months after transplantation (M2): this fell to 30.1% at 12 months. In renal calcineurin inhibitor-based immunosuppression cohort (n_73), the microchimerism negative group (n_32) showed 37.9% biopsy-proven acute rejection (BPAR), whereas in the microchimerism-positive group (n_41), no recipient did (P_0.001). Regardless of immunosuppression, BPAR incidence was 35.6% and 4.9%, respectively (P_0.001). Multivariate study showed microchimerism as a protective factor against BPAR (odds ratio: 8.3; 95% confidence interval: 1.8 to 37.9; P_0.006), blinding other well-known rejection-risk variables. Microchimerism M2 presence did not correlate with a multifactorial critical outcome such as late graft loss. Microchimerism was frequent after kidney transplantation and correlated with a significantly lower incidence of rejection. We propose that early microchimerism monitoring could help early detection of low rejection-risk recipients

Autologous cord blood in children with cerebral palsy: a review

The aim of this narrative review is to report on the current knowledge regarding the clinical use of umbilical cord blood (CB) based on articles from PubMed and clinical trials registered on ClinicalTrials.gov. An increasing amount of evidence suggests that CB may be used for both early diagnostics and treatment of cerebral palsy. The acidity of CB and its biochemical parameters, including dozens of cytokines, growth factors, and other metabolites (such as amino acids, acylcarnitines, phosphatidylcholines, succinate, glycerol, 3-hydroxybutyrate, and O-phosphocholine) are predictors of future neurodevelopment. In addition, several clinical studies confirmed the safety and efficacy of CB administration in both autologous and allogeneic models, including a meta-analysis of five clinical trials involving a total of 328 participants. Currently, nine clinical trials assessing the use of autologous umbilical CB in children diagnosed with hypoxic-ischemic encephalopathy or cerebral palsy are in progress. The total population assessed in these trials exceeds 2500 patients

Impact of Umbilical Cord Blood-Derived Mesenchymal Stem Cells on Cardiovascular Research

Over the years, cell therapy has become an exciting opportunity to treat human diseases. Early enthusiasm using adult stem cell sources has been tempered in light of preliminary benefits in patients. Considerable efforts have been dedicated, therefore, to explore alternative cells such as those extracted from umbilical cord blood (UCB). In line, UCB banking has become a popular possibility to preserve potentially life-saving cells that are usually discarded after birth, and the number of UCB banks has grown worldwide. Thus, a brief overview on the categories of UCB banks as well as the properties, challenges, and impact of UCB-derived mesenchymal stem cells (MSCs) on the area of cardiovascular research is presented. Taken together, the experience recounted here shows that UCBMSCs are envisioned as attractive therapeutic candidates against human disorders arising and/or progressing with vascular deficit

Impact of Umbilical Cord Blood-Derived Mesenchymal Stem Cells on Cardiovascular Research

Over the years, cell therapy has become an exciting opportunity to treat human diseases. Early enthusiasm using adult stem cell sources has been tempered in light of preliminary benefits in patients. Considerable efforts have been dedicated, therefore, to explore alternative cells such as those extracted from umbilical cord blood (UCB). In line, UCB banking has become a popular possibility to preserve potentially life-saving cells that are usually discarded after birth, and the number of UCB banks has grown worldwide. Thus, a brief overview on the categories of UCB banks as well as the properties, challenges, and impact of UCB-derived mesenchymal stem cells (MSCs) on the area of cardiovascular research is presented. Taken together, the experience recounted here shows that UCBMSCs are envisioned as attractive therapeutic candidates against human disorders arising and/or progressing with vascular deficit

Nanosized UCMSC-derived extracellular vesicles but not conditioned medium exclusively inhibit the inflammatory response of stimulated T cells: implications for nanomedicine

Altres ajuts: La Marató TV3 (201502 i 201516). This work has been developed in the context of AdvanceCat with the support of ACCIÓ (Catalonia Trade & Investment; Generalitat de Catalunya) under the Catalonian ERDF operational program (European Regional Development Fund) 2014-2020. FEB is sponsored by the "Researchers Stabilization Program" from the Spanish "Sistema Nacional de Salud" (SNS-ISCIII) and "Direcció d'Estratègia i Coordinació" Catalan Health Department (CES07/015).Undesired immune responses have drastically hampered outcomes after allogeneic organ transplantation and cell therapy, and also lead to inflammatory diseases and autoimmunity. Umbilical cord mesenchymal stem cells (UCMSCs) have powerful regenerative and immunomodulatory potential, and their secreted extracellular vesicles (EVs) are envisaged as a promising natural source of nanoparticles to increase outcomes in organ transplantation and control inflammatory diseases. However, poor EV preparations containing highly-abundant soluble proteins may mask genuine vesicular-associated functions and provide misleading data. Here, we used Size-Exclusion Chromatography (SEC) to successfully isolate EVs from UCMSCs-conditioned medium. These vesicles were defined as positive for CD9, CD63, CD73 and CD90, and their size and morphology characterized by NTA and cryo-EM. Their immunomodulatory potential was determined in polyclonal T cell proliferation assays, analysis of cytokine profiles and in the skewing of monocyte polarization. In sharp contrast to the non-EV containing fractions, to the complete conditioned medium and to ultracentrifuged pellet, SEC-purified EVs from UCMSCs inhibited T cell proliferation, resembling the effect of parental UCMSCs. Moreover, while SEC-EVs did not induce cytokine response, the non-EV fractions, conditioned medium and ultracentrifuged pellet promoted the secretion of pro-inflammatory cytokines by polyclonally stimulated T cells and supported Th17 polarization. In contrast, EVs did not induce monocyte polarization, but the non-EV fraction induced CD163 and CD206 expression and TNF-α production in monocytes. These findings increase the growing evidence confirming that EVs are an active component of MSC's paracrine immunosuppressive function and affirm their potential for therapeutics in nanomedicine. In addition, our results highlight the importance of well-purified and defined preparations of MSC-derived EVs to achieve the immunosuppressive effect