Therapeutic Effect of Human Adipose Tissue-Derived Mesenchymal Stem Cells in Experimental Corneal Failure Due to Limbal Stem Cell Niche Damage

Producción CientíficaLimbal stem cells are responsible for the continuous renewal of the corneal epithelium. The destruction or dysfunction of these stem cells or their niche induces limbal stem cell deficiency (LSCD) leading to visual loss, chronic pain, and inflammation of the ocular surface. To restore the ocular surface in cases of bilateral LSCD, an extraocular source of stem cells is needed to avoid dependence on allogeneic limbal stem cells that are difficult to obtain, isolate, and culture. The aim of this work was to test the tolerance and the efficacy of human adipose tissue-derived mesenchymal stem cells (hAT-MSCs) to regenerate the ocular surface in two experimental models of LSCD that closely resemble the different severity grades of the human pathology. hAT-MSCs transplanted to the ocular surface of the partial and total LSCD models developed in rabbits were well tolerated, migrated to inflamed tissues, reduced inflammation, and restrained the evolution of corneal neovascularization and corneal opacity. The expression profile of the corneal epithelial cell markers CK3 and E-cadherin, and the limbal epithelial cell markers CK15 and p63 was lost in the LSCD models, but was partially recovered after hAT-MSC transplantation. For the first time, we demonstrated that hAT-MSCs improves corneal and limbal epithelial phenotypes in animal LSCD models. These results support the potential use of hAT-MSCs as a novel treatment of ocular surface failure due to LSCD. hAT-MSCs represent an available, non-immunogenic source of stem cells that may provide therapeutic benefits in addition to reduce health care expenses.This work was supported by Instituto de Salud Carlos III, CIBER‐BBN, Spain (CB06/01/003 MINECO/FEDER, EU); Regional Center for Regenerative Medicine and Cell Therapy, Castilla y León, Spain; Ministry of Science and Innovation, Spain (SAF2010–14900); Ministry of Economy and Competitiveness and European Regional Development Fund, Spain (SAF2015–63594‐R MINECO/FEDER, EU

Eficacia del trasplante de células madre mesenquimales de médula ósea y de tejido adiposo en un modelo de deficiencia de células madre limbares desarrollado en conejo: estudio comparativo

INTRODUCCIÓN: La deficiencia de células madre limbares (LSCD, por sus siglas en inglés) se produce como resultado de la destrucción y/o disfunción de las células madre del epitelio limbar, y tiene entre sus consecuencias la pérdida de visión y la inflamación crónica de la superficie ocular. Nuestro grupo de investigación ha demostrado recientemente que el trasplante de células madre mesenquimales (MSC) derivadas de la médula ósea (BM-MSC) en la superficie ocular de pacientes que padecen LSCD es seguro y facilita de manera eficaz la reparación del epitelio corneal. Sin embargo, las MSC derivadas del tejido adiposo (AT-MSC) se ha demostrado que son más accesibles, más económicas y una fuente de células madre más segura que las BM-MSC. OBJETIVO: Comparar la eficacia del trasplante de BM-MSC versus AT-MSC en un modelo de LSCD desarrollado en conejo. MÉTODOS: Dieciocho conejos fueron tratados con 250.000 MSC cultivadas sobre una membrana amniótica (9 con BM-MSC y 9 con AT-MSC) y trasplantadas tres semanas después de inducirles un LSCD. Mediante desepitelización completa de la córnea con n-heptanol, seguida de una peritomía limbar quirúrgica de 360º, se indujo un modelo de LSCD en 27 conejos. Transcurridas 3 semanas de evolución, 18 conejos fueron trasplantados con 250.000 MSC cultivadas sobre una membrana amniótica (9 con BM-MSC y 9 con AT-MSC). Nueve conejos no trasplantados formaron el grupo de control. Semanalmente, se evaluó clínicamente la invasión conjuntival, la neovascularización, la opacidad y el defecto epitelial corneal con una lámpara de hendidura. Mediante un análisis histopatológico realizado al final del periodo del seguimiento (11 semanas), se evaluó el nivel de daño tisular y la presencia de linfocitos (como signo de inflamación) y de células caliciformes (como signo de conjuntivalización) en el limbo y en la córnea. RESULTADOS: El grupo trasplantado con BM-MSC mostró menos neovascularización y menos opacidad corneal en las semanas 6-8 y 6-9, respectivamente, que el grupo no tratado. El grupo tratado con AT-MSC tuvo menos invasión conjuntival y opacidad corneal en las semanas 6-8 y 6-10, respectivamente, que el grupo de control. No hubo diferencias en los defectos epiteliales entre los 3 grupos. Los grupos trasplantados con BM-MSC y AT-MSC mostraron un mayor número de capas epiteliales en la córnea y en el limbo, menos desorganización del estroma, menor cantidad de células inflamatorias en el estroma de la córnea y menos células caliciformes en el epitelio del limbo y/o de la córnea que el grupo no tratado. CONCLUSIONES: El trasplante de BM-MSC y AT-MSC en un modelo de LSCD desarrollado en conejo redujo el desarrollo de la opacidad corneal y restauró parcialmente la estructura dañada del tejido limbar y corneal. Las BM-MSC fueron mejores en la reducción del desarrollo de la neovascularización corneal, mientras que las AT-MSC evitaron mejor la invasión conjuntival. Ambos tipos de MSC parecen alternativas válidas para el tratamiento de la LSCD.Ministerios de Economía y Competitividad (SAF2015-63594-R MINECO/FEDER, UE) y de Ciencia e Innovación, España (SAF2010-14900); Instituto de Salud Carlos III, España (CIBER-BBN, CB06/01/003 MINECO/FEDER). Centro en Red de Medicina Regenerativa y Terapia Celular de Castilla y León, España

Transcriptome Sequencing of Peripheral Blood Mononuclear Cells from Elite Controller-Long Term Non Progressors

The elite controller (EC)-long term non-progressor (LTNP) phenotype represent a spontaneous and advantageous model of HIV-1 control in the absence of therapy. The transcriptome of peripheral blood mononuclear cells (PBMCs) collected from EC-LTNPs was sequenced by RNA-Seq and compared with the transcriptomes from other phenotypes of disease progression. The transcript abundance estimation combined with the use of supervised classification algorithms allowed the selection of 20 genes and pseudogenes, mainly involved in interferon-regulated antiviral mechanisms and cell machineries of transcription and translation, as the best predictive genes of disease progression. Differential expression analyses between phenotypes showed an altered calcium homeostasis in EC-LTNPs evidenced by the upregulation of several membrane receptors implicated in calcium-signaling cascades and intracellular calcium-mobilization and by the overrepresentation of NFAT1/Elk-1-binding sites in the promoters of the genes differentially expressed in these individuals. A coordinated upregulation of host genes associated with HIV-1 reverse transcription and viral transcription was also observed in EC-LTNPs -i.e. p21/CDKN1A, TNF, IER3 and GADD45B. We also found an upregulation of ANKRD54 in EC-LTNPs and viremic LTNPs in comparison with typical progressors and a clear alteration of type-I interferon signaling as a consequence of viremia in typical progressors before and after receiving antiretroviral therapy.We want to particularly acknowledge the patients in this study for their participation and to the HIV BioBank integrated in the Spanish AIDS Research Network and collaborating Centres (http://hivhgmbiobank.com/donor-area/hospitals-and-centres-transferring-samples/?lang = en) for the generous gifts of clinical samples used in this work. The HIV BioBank and the AIDS Immunopathogenesis Unit are integrated in the Spanish AIDS Research Network. The HIV BioBank is partially funded by the RD16/0025/0019 project as part of the Plan Nacional R + D + I and cofinanced by ISCIII- Subdirección General de Evaluación and el Fondo Europeo de Desarrollo Regional (FEDER)”. This work was partially supported by Instituto de Salud Carlos III and co-funded by European Regional Development Fund (ERDF) “A way to build Europe” (projects RD12/0017/0015 and RD16CIII/0002/0001, Plan Estatal de I + D + I 2013–2016), the French Government’s Investissement d’Avenir program, Laboratoire d’Excellence Integrative Biology of Emerging Infectious Diseases (n°ANR-10-LABX-62-IBEID) and the European Union’s Horizon 2020 Research and Innovation Programme under grant agreement No 681137. FDF was supported by the Spanish Government’s Sara Borrell postdoctoral ProgramS

Transcriptomic Evidence of the Immune Response Activation in Individuals With Limb Girdle Muscular Dystrophy Dominant 2 (LGMDD2) Contributes to Resistance to HIV-1 Infection

LGMDD2 is a rare form of muscular dystrophy characterized by one of the three heterozygous deletions described within the TNPO3 gene that result in the addition of a 15-amino acid tail in the C-terminus.TNPO3 is involved in the nuclear import of splicing factors and acts as a host cofactor for HIV-1 infection by mechanisms not yet deciphered. Further characterization of the crosstalk between HIV-1 infection and LGMDD2 disease may contribute to a better understanding of both the cellular alterations occurring in LGMDD2 patients and the role of TNPO3 in the HIV-1 cycle. To this regard, transcriptome profiling of PBMCs from LGMDD2 patients carrying the deletion c.2771delA in the TNPO3 gene was compared to healthy controls. A total of 545 differentially expressed genes were detected between LGMDD2 patients and healthy controls, with a high representation of G protein-coupled receptor binding chemokines and metallopeptidases among the most upregulated genes in LGMDD2 patients. Plasma levels of IFN-β and IFN-γ were 4.7- and 2.7-fold higher in LGMDD2 patients, respectively. An increase of 2.3-fold in the expression of the interferon-stimulated gene MxA was observed in activated PBMCs from LGMDD2 patients after ex vivo HIV-1 pseudovirus infection. Thus, the analysis suggests a pro-inflammatory state in LGMDD2 patients also described for other muscular dystrophies, that is characterized by the alteration of IL-17 signaling pathway and the consequent increase of metallopeptidases activity and TNF response. In summary, the increase in interferons and inflammatory mediators suggests an antiviral environment and resistance to HIV-1 infection but that could also impair muscular function in LGMDD2 patients, worsening disease evolution. Biomarkers of disease progression and therapeutic strategies based on these genes and mechanisms should be further investigated for this type of muscular dystrophy.This study was funded by Asociación Conquistando Escalones, French Agency for Research on AIDS and Viral Hepatitis (ANRS grant ECTZ107263), Instituto de Salud Carlos III (PI19CIII/00004), NIH grant R01AI143567, the Spanish Ministry of Science and Innovation (PID2019-110275RB I00) and Fundación Isabel Gemio. It has been conducted within the Spanish AIDS Research Network (RIS) and Centro de Investigación Biomédica en Red de Enfermedades Infecciosas, funded by Instituto de Salud Carlos 640 III (Plan Estatal de I+D+I 2013-2016) and co-funded by European Regional Development Fund (ERDF) “A way to build Europe” (RD16CIII/0002/0001).S

Characterization of LEDGF/p75 genetic variants and association with HIV-1 disease progression

BACKGROUND: As Lens epithelium-derived growth factor (LEDGF/p75) is an important co-factor involved in HIV-1 integration, the LEDGF/p75-IN interaction is a promising target for the new class of allosteric HIV integrase inhibitors (LEDGINs). Few data are available on the genetic variability of LEDGF/p75 and the influence on HIV disease in vivo. This study evaluated the relation between LEDGF/p75 genetic variation, mRNA expression and HIV-1 disease progression in order to guide future clinical use of LEDGINs. METHODS: Samples were derived from a therapy-naïve cohort at Ghent University Hospital and a Spanish long-term-non-progressor cohort. High-resolution melting curve analysis and Sanger sequencing were used to identify all single nucleotide polymorphisms (SNPs) in the coding region, flanking intronic regions and full 3'UTR of LEDGF/p75. In addition, two intronic tagSNPs were screened based on previous indication of influencing HIV disease. LEDGF/p75 mRNA was quantified in patient peripheral blood mononuclear cells (PBMC) using RT-qPCR. RESULTS: 325 samples were investigated from patients of Caucasian (n = 291) and African (n = 34) origin, including Elite (n = 49) and Viremic controllers (n = 62). 21 SNPs were identified, comprising five in the coding region and 16 in the non-coding regions and 3'UTR. The variants in the coding region were infrequent and had no major impact on protein structure according to SIFT and PolyPhen score. One intronic SNP (rs2737828) was significantly under-represented in Caucasian patients (P<0.0001) compared to healthy controls (HapMap). Two SNPs showed a non-significant trend towards association with slower disease progression but not with LEDGF/p75 expression. The observed variation in LEDGF/p75 expression was not correlated with disease progression. CONCLUSIONS: LEDGF/p75 is a highly conserved protein. Two non-coding polymorphisms were identified indicating a correlation with disease outcome, but further research is needed to clarify phenotypic impact. The conserved coding region and the observed variation in LEDGF/p75 expression are important characteristics for clinical use of LEDGINs.This work was partly supported by the Flemish Agency for Innovation by Science and Technology (CellCoVir - IWT file nr 60813). Linos Vandekerckhove is supported by the National Fund for Scientific Research – Belgium as Principal Investigator. The Spanish RIS cohort and HIV BioBank are integrated in the Spanish AIDS Research Network supported by Instituto de Salud Carlos III (Grant RD06/0006/0035) and Fundación para la Investigación y Prevención del SIDA en España (FIPSE). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.S

Antiviral, Immunomodulatory and Antiproliferative Activities of Recombinant Soluble IFNAR2 without IFN-beta Mediation

Soluble receptors of cytokines are able to modify cytokine activities and therefore the immune system, and some have intrinsic biological activities without mediation from their cytokines. The soluble interferon beta (IFN-ss) receptor is generated through alternative splicing of IFNAR2 and has both agonist and antagonist properties for IFN-ss, but its role is unknown. We previously demonstrated that a recombinant human soluble IFN-ss receptor showed intrinsic therapeutic efficacy in a mouse model of multiple sclerosis. Here we evaluate the potential biological activities of recombinant sIFNAR2 without the mediation of IFN-ss in human cells. Recombinant sIFNAR2 down-regulated the production of IL-17 and IFN-? and reduced the cell proliferation rate. Moreover, it showed a strong antiviral activity, fully protecting the cell monolayer after being infected by the virus. Specific inhibitors completely abrogated the antiviral activity of IFN-ss, but not that of the recombinant sIFNAR2, and there was no activation of the JAK-STAT signaling pathway. Consequently, r-sIFNAR2 exerts immunomodulatory, antiproliferative and antiviral activities without IFN-ss mediation, and could be a promising treatment against viral infections and immune-mediated diseases

Generating new fanca-deficient hnscc cell lines by genomic editing recapitulates the cellular phenotypes of fanconi anemia

Fanconi anemia (FA) patients have an exacerbated risk of head and neck squamous cell carcinoma (HNSCC). Treatment is challenging as FA patients display enhanced toxicity to standard treatments, including radio/chemotherapy. Therefore, better therapies as well as new disease models are urgently needed. We have used CRISPR/Cas9 editing tools in order to interrupt the human FANCA gene by the generation of insertions/deletions (indels) in exon 4 in two cancer cell lines from sporadic HNSCC having no mutation in FA-genes: CAL27 and CAL33 cells. Our approach allowed efficient editing, subsequent purification of single-cell clones, and Sanger sequencing validation at the edited locus. Clones having frameshift indels in homozygosis did not express FANCA protein and were selected for further analysis. When compared with parental CAL27 and CAL33, FANCA-mutant cell clones displayed a FA-phenotype as they (i) are highly sensitive to DNA interstrand crosslink (ICL) agents such as mitomycin C (MMC) or cisplatin(ii) do not monoubiquitinate FANCD2 upon MMC treatment and therefore (iii) do not form FANCD2 nuclear foci, and (iv) they display increased chromosome fragility and G2 arrest after diepoxybutane (DEB) treatment. These FANCA-mutant clones display similar growth rates as their parental cells. Interestingly, mutant cells acquire phenotypes associated with more aggressive disease, such as increased migration in wound healing assays. Therefore, CAL27 and CAL33 cells with FANCA mutations are phenocopies of FA-HNSCC cells

Longer intervals between SARS-CoV-2 infection and mRNA-1273 doses improve the neutralization of different variants of concern

The humoral immune response against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern elicited by vaccination was evaluated in COVID-19 recovered individuals (Rec) separated 1-3 months (Rec2m) or 4-12 months (Rec9m) postinfection and compared to the response in naïve participants. Antibody-mediated immune responses were assessed in 66 participants by three commercial immunoassays and a SARS-CoV-2 lentiviral-based pseudovirus neutralization assay. Immunoglobulin (Ig) levels against SARS-CoV-2 spike were lower in naïve participants after two doses than in Rec after a single dose (p < 0.05). After two doses in Rec, levels of total Ig to receptor-binding domain were significantly increased in Rec9m compared to Rec2m (p < 0.001). The neutralizing potency observed in Rec9m was consistently higher than in Rec2m against variants of concern (VOCs) Alpha, Beta, Delta, and BA.1 sublineage of Omicron with 2.2-2.8-fold increases. Increasing the interval between SARS-CoV-2 infection and the vaccination with messenger RNA-based vaccines to more than 3 months generates a more efficient heterologous humoral immune response against VOCs by allowing enough time to mount a strong recall memory B cell response.This work is funded by Instituto de Salud Carlos III, a Spanish public body assigned to the Ministry of Science and Innovation that manages and promotes public clinical research related to Public Health, by Grants PI19CIII/00004 (José Alcamí and Francisco Díez‐Fuertes) and PI21CIII/00025 (Javier García‐Pérez and Mayte Pérez‐Olmeda), COVID‐19 Fund (Grants COV20/00679 (Javier García‐Pérez, Mayte Pérez‐Olmeda, José Alcamí, and Francisco Díez‐Fuertes) and COV20/00072 (Javier García‐Pérez, Mayte Pérez‐Olmeda, Almudena Ramírez‐García, María Castillo de la Osa, Rocio Layunta Acero, Laura Vicente‐Izquierdo, Cristina Avendaño‐Solá, and José Alcamí), and CIBERINFEC, co‐financed by the European Regional Development Fund (FEDER) “A way to make Europe.”S