Role of Folic Acid in the Therapeutic Action of Nanostructured Porous Silica Functionalized with Organotin(IV) Compounds against Different Cancer Cell Lines

The synthesis, characterization and cytotoxic activity against different cancer cell lines of various mesoporous silica-based materials containing folate targeting moieties and a cytotoxic fragment based on a triphenyltin(IV) derivative have been studied. Two different mesoporous nanostructured silica systems have been used: firstly, micronic silica particles of the MSU-2 type and, secondly, mesoporous silica nanoparticles (MSNs) of about 80 nm. Both series of materials have been characterized by different methods, such as powder X-ray diffraction, X-ray fluorescence, absorption spectroscopy and microscopy. In addition, these systems have been tested against four different cancer cell lines, namely, OVCAR-3, DLD-1, A2780 and A431, in order to observe if the size of the silica-based systems and the quantity of incorporated folic acid influence their cytotoxic action. The results show that the materials are more active when the quantity of folic acid is higher, especially in those cells that overexpress folate receptors such as OVCAR-3 and DLD-1. In addition, the study of the potential modulation of the soluble folate receptor alpha (FOLR1) by treatment with the synthesized materials has been carried out using OVCAR-3, DLD-1, A2780 and A431 tumour cell lines. The results show that a relatively high concentration of folic acid functionalization of the nanostructured silica together with the incorporation of the cytotoxic tin fragment leads to an increase in the quantity of the soluble FOLR1 secreted by the tumour cells. In addition, the studies reported here show that this increase of the soluble FOLR1 occurs presumably by cutting the glycosyl-phosphatidylinositol anchor of membrane FR-α and by the release of intracellular FR-α. This study validates the potential use of a combination of mesoporous silica materials co-functionalized with folate targeting molecules and an organotin(IV) drug as a strategy for the therapeutic treatment of several cancer cells overexpressing folate receptors.Spanish Government RTI2018-094322-B-I00 CTQ2017-90802-REDTMinistry of Research and Innovation, CNCS-UEFISCDI within PNCDI III PN-III-P4-ID-PCCF-2016-014

Oxygen Saturation on Admission Is a Predictive Biomarker for PD-L1 Expression on Circulating Monocytes and Impaired Immune Response in Patients With Sepsis

Sepsis is a pathology in which patients suffer from a proinflammatory response and a dysregulated immune response, including T cell exhaustion. A number of therapeutic strategies to treat human sepsis, which are different from antimicrobial and fluid resuscitation treatments, have failed in clinical trials, and solid biomarkers for sepsis are still lacking. Herein, we classified 85 patients with sepsis into two groups according to their blood oxygen saturation (SaO2): group I (SaO2 ≤ 92%, n = 42) and group II (SaO2 > 92%, n = 43). Blood samples were taken before any treatment, and the immune response after ex vivo LPS challenge was analyzed, as well as basal expression of PD-L1 on monocytes and levels of sPD-L1 in sera. The patients were followed up for 1 month. Taking into account reinfection and exitus frequency, a significantly poorer evolution was observed in patients from group I. The analysis of HLA-DR expression on monocytes, T cell proliferation and cytokine profile after ex vivo LPS stimulation confirmed an impaired immune response in group I. In addition, these patients showed both, high levels of PD-L1 on monocytes and sPD-L1 in serum, resulting in a down-regulation of the adaptive response. A blocking assay using an anti-PD-1 antibody reverted the impaired response. Our data indicated that SaO2 levels on admission have emerged as a potential signature for immune status, including PD-L1 expression. An anti-PD-1 therapy could restore the T cell response in hypoxemic sepsis patients with SaO2 ≤ 92% and high PD-L1 levels

Cellular and humoral functional responses after BNT162b2 mRNA vaccination differ longitudinally between naive and subjects recovered from COVID-19

We have analyzed BNT162b2 vaccine-induced immune responses in naive subjects and individuals recovered from coronavirus disease 2019 (COVID-19), both soon after (14 days) and later after (almost 8 months) vaccination. Plasma spike (S)-specific immunoglobulins peak after one vaccine shot in individuals recovered from COVID-19, while a second dose is needed in naive subjects, although the latter group shows reduced levels all along the analyzed period. Despite how the neutralization capacity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mirrors this behavior early after vaccination, both groups show comparable neutralizing antibodies and S-specific B cell levels late post-vaccination. When studying cellular responses, naive individuals exhibit higher SARS-CoV-2-specific cytokine production, CD4+ T cell activation, and proliferation than do individuals recovered from COVID-19, with patent inverse correlations between humoral and cellular variables early post-vaccination. However, almost 8 months post-vaccination, SARS-CoV-2-specific responses are comparable between both groups. Our data indicate that a previous history of COVID-19 differentially determines the functional T and B cell-mediated responses to BNT162b2 vaccination over time.C.d.F., J.G.-P., and J.A. are supported by Instituto de Salud Carlos III (ISCII). We thank JM Ligos and Cytek Biosciences for their technical support. Research in E.L.-C.’s lab was supported by Fundación Familia Alonso, Santander Bank, Real Seguros, Fundación Mutua Madrileña, Fundación Uria, Fundación La Caixa, and Ayuntamiento de Madrid.S

Cáncer de Colon: un acercamiento desde la inmunología

Tesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Medicina, Departamento de Bioquímica. Fecha de Lectura: 30-09-2022Esta tesis tiene embargado el acceso al texto completo hasta el 30-03-2024Cellular fusion exists as a physiological mechanism which is involved in essential processes such as fertilisation and osteoclasts formation. However, every physiological pathway can become pathological if aberrant. In this regard, cancer cell fusion has emerged as an alternative mechanism that aims to explain most of the poorly understood hallmarks of cancer. In this work, we have evaluated the cell fusion between colon cancer stem cells and human monocytes, together with the characterisation of the resulting tumour hybrid cells (THCs). THCs resulted after a 5-day in vitro co-culture between colon cancer stem cells and human monocytes, and these were identified as CD45+CD14+EpCAM+. Functional assays showed enhanced migratory and proliferation abilities of these THCs when compared to their parental cells. Moreover, when sorted THCs, EpCAM+ colon cancer stem cells and CD14+ human monocytes were co-cultured with human peripheral blood mononuclear cells (PBMCs), proliferation of T lymphocytes was lower in the presence of THCs, supporting their immune evasion abilities. Not only that, when a blocking antibody against SIGLEC5 was used, CD4 T cell proliferation was recovered, showing the involvement of SIGLEC5 in the immune evasion mechanisms of THCs. Moving on to patients, THCs were identified in circulation and tumour tissue samples of colon cancer patients with the same CD45+CD14+EpCAM+ signature. Next, an array of soluble immune-checkpoints (ICs) were characterised in the plasma samples of our colon cancer patient cohort. Within these, levels of soluble SIGLEC5 (sSIGLEC5) were found to be significantly higher in patients compared to healthy volunteers (HVs). Furthermore, concentration of sSIGLEC5 was found significantly higher in exitus patients. Following a logistic regression model including 22 variables, sSIGLEC5 was found to be an independent survival marker in colon cancer patients. Altogether, these data support a novel role of SIGLEC5 as an immune evasion mechanism for THCs and as potent exitus predictor in colon cancer patients. These results open new paths towards the identification of novel biomarkers which could aid in patient stratificationEste trabajo fue apoyado por los siguientes proyectos y ayudas: • Fundación Familia Alonso • Fundación La Caixa (ID100010434) • Marie Sklodowska-Curie (grant agreement No. 713673

MV130 in the Prevention of Recurrent Respiratory Tract Infections: A Retrospective Real-World Study in Children and Adults

Respiratory tract infections (RTIs) are among the most common and important problems in clinical medicine, making antibiotics the gold standard therapeutic option regardless of their frequent viral etiology. Their excessive and inappropriate use contributes to the rapid rise of antibiotic resistance and underscores the need for alternative strategies, especially when dealing with recurrent RTIs. Prevention is the ideal alternative, but specific vaccines targeting a wide range of respiratory pathogens are scarce. MV130 is a sublingual bacterial vaccine that induces trained immunity and provides non-specific protection against respiratory pathogens in various clinical settings according to the concept of TIbV (Trained Immunity-based Vaccine). A retrospective real-world study (RWS) was conducted to evaluate the annual incidence of RTIs and the consumption of antibiotics before and after the administration of MV130, using data sourced from the medical records of 599 patients (186 children and 413 adults) who suffered from recurrent RTIs. The median number of infectious episodes in children was significantly reduced by more than 70% from 5 episodes (interquartile range (IQR) 4.0–6.0) to 1 (IQR, 0.0–2.0) (p p p < 0.001). This RWS showed that MV130 is an effective strategy for the prevention of respiratory infections and the reduction of associated antibiotic consumption

Identification of sSIGLEC5 and sLAG3 as New Relapse Predictors in Lung Cancer

Lung cancer (LC) continues to be the leading cause of cancer-related deaths in both men and women worldwide. After complete tumour resection, around half of the patients suffer from disease relapse, emphasising the critical need for robust relapse predictors in this disease. In search of such biomarkers, 83 patients with non-microcytic lung cancer and 67 healthy volunteers were studied. Pre-operative levels of sSIGLEC5 along with other soluble immune-checkpoints were measured and correlated with their clinical outcome. Soluble SIGLEC5 (sSIGLEC5) levels were higher in plasma from patients with LC compared with healthy volunteers. Looking into those patients who suffered relapse, sSIGLEC5 and sLAG3 were found to be strong relapse predictors. Following a binary logistic regression model, a sSIGLEC5 + sLAG3 score was established for disease relapse prediction (area under the curve 0.8803, 95% confidence intervals 0.7955&ndash;0.9652, cut-off &gt; 2.782) in these patients. Based on score cut-off, a Kaplan&ndash;Meier analysis showed that patients with high sSIGLEC5 + sLAG3 score had significantly shorter relapse-free survival (p &le; 0.0001) than those with low sSIGLEC5 + sLAG3 score.Our study suggests that pre-operative sSIGLEC5 + sLAG3 score is a robust relapse predictor in LC patients

PD-L1/PD-1 crosstalk in colorectal cancer: are we targeting the right cells?

Abstract Background The analysis of tumour-infiltrating immune cells within patients’ tumour samples in colorectal cancer (CRC) has become an independent predictor of patient survival. The tumour microenvironment and the immune checkpoints, such as PD-L1/PD-1, are relevant to the prognoses and also appear to be relevant for further CRC therapies. Methods We analysed the presence and features of the infiltrated monocyte/macrophage and lymphocyte populations in both tumour and peritumour samples from patients with CRC (n = 15). Results We detected a large number of CD14+ monocytes/macrophages with an alternative phenotype (CD64+CD163+) and CD4+ lymphocytes that infiltrated the tumour, but not the peritumour area. The monocytes/macrophages expressed PD-L1, whereas the lymphocytes were PD-1+; however, we did not find high PD-L1 levels in the tumour cells. Coculture of circulating naïve human monocytes/macrophages and lymphocytes with tumour cells from patients with proficient mismatch repair CRC induced both an alternative phenotype with higher expression of PD-L1 in CD14+ cells and the T-cell exhaustion phenomenon. The addition of an α-PD-1 antibody restored lymphocyte proliferation. Conclusion These results emphasise the interesting nature of immune checkpoint shifting therapies, which have potential clinical applications in the context of colorectal cancer

Soluble SIGLEC5: A New Prognosis Marker in Colorectal Cancer Patients

Colorectal cancer (CRC) is the second most deadly and third most commonly diagnosed cancer worldwide. There is significant heterogeneity among patients with CRC, which hinders the search for a standard approach for the detection of this disease. Therefore, the identification of robust prognostic markers for patients with CRC represents an urgent clinical need. In search of such biomarkers, a total of 114 patients with colorectal cancer and 67 healthy participants were studied. Soluble SIGLEC5 (sSIGLEC5) levels were higher in plasma from patients with CRC compared with healthy volunteers. Additionally, sSIGLEC5 levels were higher in exitus than in survivors, and the receiver operating characteristic curve analysis revealed sSIGLEC5 to be an exitus predictor (area under the curve 0.853; cut-off &gt; 412.6 ng/mL) in these patients. A Kaplan–Meier analysis showed that patients with high levels of sSIGLEC5 had significantly shorter overall survival (hazard ratio 15.68; 95% CI 4.571–53.81; p ≤ 0.0001) than those with lower sSIGLEC5 levels. Our study suggests that sSIGLEC5 is a soluble prognosis marker and exitus predictor in CRC