CD40 Ligand Research Articles

Microglia in the spinal cord stem cell niche regulate neural precursor cell proliferation via soluble CD40 in response to myelin basic protein.

Neural stem cells (NSCs) are found along the neuraxis of the developing and mature central nervous system. They are found in defined niches that have been shown to regulate NSC behaviour in a regionally distinct manner. Specifically, previous research has shown that myelin basic protein (MBP), when presented in the spinal cord niche, inhibits NSC proliferation and oligodendrogenesis. Herein, we investigate the cell-based mechanism(s) underlying this spinal-cord niche derived MBP-mediated inhibition. We used reporter mice to sort for subpopulations of cells and found that spinal cord niche derived microglia release a soluble factor in response to MBP that is responsible for NSC inhibition. Microglia, but not other niche cells, release soluble CD40/TNFRSF5 (sCD40) in the presence of MBP which may indirectly reduce activation of transmembrane CD40/TNFRSF5 receptor on both spinal cord and brain NSCs. This is consistent with sCD40 binding to CD40 ligand (CD40L) thereby preventing CD40 receptor binding on NSCs and inhibiting NSC proliferation. The identification of the cell-based mechanism that regulates NSC behaviour in response to MBP, which is dysregulated in injury/disease, provides insight into a potential target for strategies to enhance neural repair through endogenous stem cell activation.

Mechanotransduction governs CD40 function and underlies X-linked hyper-IgM syndrome.

B cell maturation depends on cognate interactions between the T and B cells. Upon interaction with CD40 ligand (CD40L) on T cells, CD40 delivers costimulatory signals alongside B cell antigen receptor (BCR) signaling to regulate affinity maturation and antibody class switch. Mutations affecting CD40-CD40L interactions cause abnormal antibody responses in immunodeficiencies known as X-linked hyper-IgM syndrome (X-HIgM). Here, we study the CD40-mediated mechanotransduction in B cells, which likely occurs during their physical contacts with T cells. We found that CD40 forms catch bond with CD40L that lasts longer at larger forces, both B and T cells exert tension on CD40-CD40L bonds, and force enhances CD40 signaling and antibody class switch. X-HIgM CD40L mutations impair catch bond formation, suppress endogenous tension, and reduce force-enhanced CD40 signaling, leading to deficiencies in antibody class switch. Our findings highlight the role of mechanotransduction in CD40 function and provide insights into the mechanisms underlying X-HIgM syndrome.

CD47 and thrombospondin-1 contribute to immune evasion by Porphyromonas gingivalis

Porphyromonas gingivalis is a gram-negative anaerobic bacterium linked to periodontal disease. Remarkably, P. gingivalis thrives in an inflamed environment rich in activated neutrophils. Toll-like receptor 2 (TLR2) recognition is required for P. gingivalis to evade innate immune killing; however, the mechanisms through which P. gingivalis uncouples host inflammation from bactericidal activity are only partially known. Since integrin activation and alternative signaling are implicated in P. gingivalis TLR2-mediated immune escape, we explored the role of CD47, a widely expressed integrin-associated protein known to suppress phagocytosis and implicated as an interacting partner with other innate immune receptors. We found that CD47 associates with TLR2, and blocking CD47 leads to decreased intracellular P. gingivalis survival in macrophages in a manner dependent on the bacterial major fimbria. In vivo, CD47 knock-out mice cleared P. gingivalis more efficiently than wild-type mice. Next, we found increased expression and secretion of the CD47 ligand thrombospondin-1 (TSP-1) following P. gingivalis infection. Secreted TSP-1 broadly protected P. gingivalis and other periodontitis-associated bacterial species from neutrophil bactericidal activity. Therefore, CD47-TLR2 cosignaling in response to P. gingivalis induces TSP-1 that in turn suppresses neutrophil activity, an effect that can explain how species such as P. gingivalis survive in an inflamed environment and cause dysbiosis.

CD34+ and CD34- MM cells show different immune-checkpoint molecule expression profiles: high expression of CD112 and CD137 ligand on CD34+ MM cells.

Despite the introduction of new drugs, multiple myeloma (MM) still remains incurable. We previously reported that CD34+ MM cells, which are clonogenic and self-renewing, are therapy-resistant and persist as a major component of minimal residual disease, expanding during relapse. To investigate the effects of immunotherapies such as immune-checkpoint inhibitors, CAR-T therapy, and bispecific antibodies on CD34+ MM cells, we analyzed immune profiles of both MM cells and T cells from MM patients using microarrays and flow cytometry. Ingenuity pathway analysis revealed 14 out of 289 canonical pathways were more active in CD34+ MM cells compared to CD34- cells, many of which were involved in inflammation and immune responses. Notably, PD-1 signaling-related genes were highly expressed in CD34+ MM cells. Among 10 immune-checkpoint molecules, CD34+ cells more frequently expressed CD112, CD137L, CD270, CD275, and GAL9 than CD34- cells in both newly diagnosed and relapsed/resistant patients. In addition, CD4+ and CD8+ T cells more frequently expressed TIGIT and CD137, suggesting that CD112/TIGIT and CD137L/CD137 interactions may suppress T-cell activity against CD34+ MM cells. Furthermore, our finding of higher FcRH5 expression on CD34+ MM cells is encouraging for future research into the efficacy of FcRH5-targeted therapy in MM.

Dissecting Immunological Mechanisms Underlying Influenza Viral Nucleoprotein-induced Mucosal Immunity Against Diverse Viral Strains

The nucleoprotein (NP) of type A influenza virus (IAV) is highly conserved across all virus strains, making it an attractive candidate antigen for universal vaccines. While various studies have explored NP-induced mucosal immunity, here we interrogated the mechanistic differences between intramuscular (IM) and intranasal (IN) delivery of a recombinant adenovirus carrying NP fused with a bifunctional CD40 ligand. Despite being less effective than IM delivery in inducing systemic cellular immune responses and antibody-dependent cellular cytotoxicity (ADCC), IN immunization elicited superior antigen-specific recall humoral and cellular response in the nasal associated lymphoid tissue (NALT) of the upper respiratory tract, the initial site of immune recognition and elimination of inhaled pathogens. IN vaccination also induced significantly stronger pulmonary T cell responses in the lower respiratory tract than IM vaccination, in particular the CD8 T cells. Moreover, blocking lymphocyte circulation abrogated IM but not IN immunization induced protection, illustrating the critical role of local memory immune response upon viral infection. Notably, the CD40-targeted nasal delivery not only improved the magnitude but also the breadth of protection, including against lethal challenge with a newly isolated highly pathogenic avian H5N1 strain. These findings are informative for the design of universal mucosal vaccines, where the predominant mode of protection is independent of neutralizing antibodies.

EXTH-32. DUAL TARGETING OF CD155/TIGIT AND PD-L1/PD-1 IMMUNE CHECKPOINTS POTENTIATES NATURAL KILLER CELL-MEDIATED CYTOTOXICITY IN MEDULLOBLASTOMA

Abstract Medulloblastoma (MB) is one of the most prevalent pediatric brain malignancies and makes up approximately 20% of all primary brain tumors in children. Current treatment options are not curative for about 30% of patients and leave survivors with an impaired quality of life. Immune checkpoint inhibition can offer a novel targeted therapy but largely remains understudied in MB. The aim of this study was to determine whether immune checkpoint inhibition can be used as a novel targeted therapy in MB. We used MB cell lines, MB patient-derived xenograft (PDX) organoid models, and primary patient-derived MB tissue to study immune checkpoints and their blockade to target MB. We identified the expression of immune checkpoint protein TIGIT on immune cells and its high-affinity ligand CD155 in medulloblastoma patient-derived tissues, cell lines, and PDX MB organoids. In addition, while MB shows weak, if any, PD-L1 protein expression, we found that MB cells can upregulate PD-L1 expression upon stimulation by natural killer (NK) cells via interferon-γ as a putative immune evasive strategy. Subsequent immunotherapeutic interventions with FDA-approved antibodies Tiragolumab (anti-TIGIT), Durvalumab (anti-PD-L1), and their combination potentiated primary NK cell activation and killing of MB cell lines and PDX-derived MB organoids. These data propose a translatable and novel immunotherapeutic strategy for patients diagnosed with MB.

Spatial and Single Cell Analyses Reveal Heterogeneity of DNAM-1 Receptor-Ligand Interactions that Instructs Intratumoral γδT-Cell Activity.

The dynamic interplay between tumor cells and γδT cells within the tumor microenvironment (TME) significantly influences disease progression and immunotherapy outcome. Here, we delved into the modulation of γδT-cell activation by tumor cell ligands CD112 and CD155, which interact with the activating receptor DNAM-1 on γδT cells. Spatial and single cell RNA sequencing (scRNA-seq), as well as spatial metabolome analysis, from neuroblastoma (NB) revealed that the expression levels and localization of CD112 and CD155 varied across and within tumors, correlating with differentiation status, metabolic pathways, and ultimately disease prognosis and patient survival. Both in vivo tumor xenograft experiments and in vitro co-culture experiments demonstrated that a high CD112/CD155 expression ratio in tumors enhanced γδT-cell-mediated cytotoxicity, while a low-ratio fostered tumor resistance. Mechanistically, CD112 sustained DNAM-1-mediated γδT-cell activation, whereas CD155 downregulated DNAM-1 expression via TRIM21-mediated ubiquitin proteasomal degradation. By interacting with tumor cells differentially expressing CD112 and CD155, intratumoral γδT cells exhibited varying degrees of activation and DNAM-1 expression, representing three major functional subsets. This study underscores the complexity of tumor-immune crosstalk, offering insights into how tumor heterogeneity shapes the immune landscape.

A B7-H3–Targeted CD28 Bispecific Antibody Enhances the Activity of Anti–PD-1 and CD3 T-cell Engager Immunotherapies

Abstract T-cell activation is a multistep process requiring T-cell receptor engagement by peptide–MHC complexes (Signal 1) coupled with CD28-mediated costimulation (Signal 2). Tumors typically lack expression of CD28 ligands, so tumor-specific Signal 1 (e.g., neoepitope presentation) without costimulation may be ineffective or even induce T-cell anergy. We designed the bispecific antibody XmAb808 to co-engage the tumor-associated antigen B7-H3 with CD28 to promote T-cell costimulation within the tumor microenvironment. XmAb808 costimulation was measured by its ability to activate and expand T cells and enhance T cell–mediated cancer cell killing in cocultures of human peripheral blood mononuclear cells and cancer cells and in mice engrafted with human peripheral blood mononuclear cells and tumor xenografts. XmAb808 avidly bound cancer cells and stimulated IL2 and IFNγ secretion from T cells cocultured with cancer cells engineered to deliver Signal 1 to T cells via a surface-expressed anti-CD3 antibody. XmAb808 enhanced expression of the antiapoptotic factor Bcl-xL and CD25, promoting survival and IL2-dependent expansion of T cells coupled with increased T cell–mediated cytotoxicity in vitro. XmAb808 combined with an EpCAM×CD3 bispecific antibody to enhance target cell killing through IL2-dependent expansion of CD25+ T cells. This combination also suppressed pancreatic tumor xenograft growth in mice. Furthermore, XmAb808 combined with an anti–programmed cell death protein 1 antibody to suppress breast tumor xenograft growth in mice. XmAb808 as monotherapy and in combination with an anti–programmed cell death protein 1 antibody is currently in clinical development in patients with advanced solid tumors. Our results suggest that XmAb808 may also combine with tumor antigen–targeted anti-CD3 (Signal 1) T-cell engagers.

Comprehensive serum biomarker analysis reveals IL-8 changes as the only predictor of the effectiveness of immune checkpoint inhibitors for patients with advanced non-small cell lung cancer

ObjectivesProgrammed cell death ligand 1 (PD-L1) expression is widely used to predict the effectiveness of PD-(L)1 inhibitors despite its imperfection. Previous studies suggested the utilization of various serum biomarkers; nonetheless, findings are inconclusive because of limited sample sizes or the focus on a single biomarker in many of these studies. This study analyzed multiplex serum biomarkers to explore their predictive ability in a large cohort of patients with advanced non-small-cell lung cancer (NSCLC) treated with a PD-L1 inhibitor in a real-world setting. Materials and MethodsThis was a sub-study of J-TAIL, a prospective observational study of atezolizumab monotherapy in pre-treated patients with advanced NSCLC. From April to October 2019, 262 patients were enrolled from 73 sites in Japan. Serum samples were collected at baseline and at the second dose of atezolizumab. Quantification of the 51 serum cytokines, chemokines, growth factors, and vascular endothelial growth factors was performed using the Luminex platform. Baseline values and fold changes of the time of the second dose to the baseline were examined in association with the effectiveness of atezolizumab. ResultsAmong the 51 proteins assessed, a higher baseline interleukin (IL)-12 level, a higher soluble CD40 ligand fold change, a lower IL-8 fold change were associated with higher objective response rate (ORR). Of these, only the lower IL-8 fold change was associated with better progression-free survival (PFS) (adjusted hazard ratio, 1.98; 95 % confidence interval, 1.45–2.70; P < 0.01). Multivariate analysis demonstrated that the lower IL-8 fold change was an independent factor for both the ORR and PFS. The IL-8 fold change was independent of the neutrophil/lymphocyte ratio, and durable PFS was observed in patients with both low. ConclusionComprehensive serum biomarker analysis revealed that a lower fold change in serum IL-8 was associated with better outcomes in pre-treated patients with advanced NSCLC receiving atezolizumab.

The diagnostic value and validation of IL-22 combimed with sCD40L in tuberculosis pleural effusion

BackgroundThere is substantial evidence indicating that cytokines play a role in the immune defense against tuberculosis. This study aims to evaluate the levels of various cytokines in pleural effusion to ditinguish between tuberculosis pleurisy and malignant pleurisy.MethodsA total of 82 participants with pleural effusion were included in the training cohort, and 76 participants were included in the validation cohort. The individuals were divided into tuberculosis and malignant pleurisy groups. The concentrations of interleukin-1β (IL-1β), IL-4, IL-6, IL-10, IL-17 A, IL-17 F, IL-21, IL-22, IL-25, IL-31, IL-33, interferon-γ (IFN-γ), soluble CD40 ligand (sCD40L) and tumor necrosis factor-α (TNF-α) in pleural effusion were measured using a multiplex cytokine assay. The threshold values were calculated according to the receiver operating characteristic (ROC) curve analysis to aid in diagnosing tuberculosis pleurisy. Furthermore, the combined measure was validated in the validation cohort.ResultsThe levels of all 14 cytokines in pleural effusion were significantly higher in participants with tuberculosis compared to those with malignant pleurisy (all P < 0.05). The area under the curve (AUC) was ≥ 0.920 for the IL-22, sCD40L, IFN-γ, TNF-α and IL-31, which were significantly increased in tuberculous pleural effusion (TPE) compared to MPE in the training cohort. Threshold values of 95.80 pg/mL for IFN-γ, 41.80 pg/mL for IL-31, and 18.87 pg/mL for IL-22 provided ≥ 90% sensitivity and specificity in distinguishing between tuberculosis pleurisy and malignant pleurisy in the training cohort. Among these, IL-22 combined with sCD40L showed the best sensitivity and specificity (94.0% and 96.9%) for diagnosing tuberculosis pleurisy, and this finding was validated in the validation cohort.ConclusionWe demonstrated that the levels of IL-1β, IL-4, IL-6, IL-10, IL-17 A, IL-17 F, IL-21, IL-22, IL-25, IL-31, IL-33, IFN-γ, sCD40L and TNF-α in pleural effusion had significant difference between tuberculosis pleurisy and malignant pleurisy. Specifically, IL-22 ≥ 18.87 pg/mL and sCD40L ≥ 53.08 pg/mL can be clinically utilized as an efficient diagnostic strategy for distinguishing tuberculosis pleurisy from malignant pleurisy.

B-343 Development of CD40 and HER2 Bispecific Antibodies for Enhanced Efficacy against HER2-Positive Tumors

Abstract Background CD40, a member of the tumor necrosis factor superfamily, is primarily expressed on antigen-presenting cells. This receptor plays a crucial role in facilitating the interaction between dendritic cells, activating antigen-specific T cells. Agonist antibodies targeting the CD40 receptor have the potential to mimic the natural CD40 ligand, fostering dendritic cell maturation and stimulating immunity against “cold” tumors. Although this approach has shown promise in preclinical studies, translating it to clinical success has been challenging. Only modest anti-tumor activity was observed in cancer patients, and none of the developed CD40 monoclonal antibodies (mAbs) progressed beyond early clinical trials, highlighting a need for improved anti-tumor efficacy. Methods In this study, we successfully developed an anti-human CD40 agonist rabbit monoclonal antibody using Yurogen's proprietary SMAB(TM) platform. The most potent CD40 mAb clone was combined with trastuzumab (an anti-HER2 mAb) to create a therapeutic bispecific antibody. Our goal is to leverage immune cell activation through HER2-targeted cancer therapy to achieve enhanced anti-tumor activity. Dozens of diverse CD40xHER2 bispecific antibody designs (both symmetry and asymmetry) were explored, with careful evaluation of expression yield, purity, and binding profiles for each target respectively. Results A few bispecific antibody designs demonstrated robust binding to both HER2 and CD40 antigen proteins, as well as receptor-expressing cell lines. Notably, two developed bispecific antibodies exhibited potent killing of HER2-positive cancer cells with the assistance of innate immune cells. Conclusions In sum, this study provides novel insights into designing bispecific antibodies against HER2 and CD40, offering a promising avenue for advancing cancer immunotherapy.

Influence of hyaluronic acid and chitosan molecular weight on the adhesion of circulating tumor cell on multilayer films

CD44 is a cell receptor glycoprotein overexpressed in circulating tumor cells (CTCs), with levels linked to an increase in metastatic capacity of several tumors. Hyaluronic acid (HA), the natural ligand of CD44, has primarily been investigated for tumor cell interaction in self-assembled polyelectrolyte multilayer films, with little attention given to the complementary polycation. In this study, we screened sixteen different polyelectrolyte multilayer assemblies of HA and chitosan (CHI) to identify key assembly parameters and surface properties that control and govern CTCs adhesion. Statistics analysis revealed a major role of CHI molecular weight in the adhesion, followed by its combinatorial response either with HA ionization degree or ionic strength. PM-IRRAS analysis demonstrated a correlation between the orientation of HA carboxyl groups on the film surface and CTCs adhesion, directly impacted by CHI molecular weight. Overall, although CTCs binding onto the surface of multilayer films is primarily driven by HA-CD44 interaction, both chitosan properties and film assembly conditions modulate this interaction. These findings illustrate an alternative to modifying the performance of biomaterials with minimal changes in the composition of multilayer films.

Implications of CD154 and Its Receptors in the Pathogenesis and Treatment of Systemic Lupus Erythematosus.

CD154, also known as CD40 ligand, is a costimulatory molecule involved in humoral and adaptive immune responses upon pairing with its classical receptor, CD40. The CD154/CD40 dyad is a key participant in the pathogenesis of many autoimmune diseases, including systemic lupus erythematosus (SLE). In SLE, the major cells at play, T and B lymphocytes, are shown to overexpress CD154 and CD40, respectively. Subsequently, these cells and other CD40-positive cells engage in numerous effector functions contributing to SLE development. With the recent identification of additional receptors for CD154, all belonging to the integrin family, the role of CD154 in SLE is more complex and calls for deeper investigation into its biological significance. Many therapeutic strategies directed against the CD154/CD40 couple have been deployed for the treatment of SLE and proved efficient in animal models and human studies. However, the incidence of thromboembolic complications in patients treated with these anti-CD154/CD40 antibodies halted their further clinical assessments and called for another class of therapies targeting these molecules. Second-generation antibodies directed against CD154 or CD40 are showing promising results in the advanced stages of clinical testing. Our review presents a thorough description of CD154 and its receptors, CD40 and the integrin family members in SLE pathogenesis. All these elements of the CD154 system represent important therapeutic targets for the treatment of SLE.

Investigating soluble CD40 ligand as a prognostic factor among acute coronary syndromes patients: A multi-center prospective case-control study.

Soluble CD40 ligand (sCD40L) is a protein that plays a crucial role in the inflammatory response associated with the development and progression of acute coronary syndrome (ACS). Recent studies have suggested that sCD40L may be a useful prognostic factor for ACS, but the data are conflicting. This study aimed to investigate the potential of sCD40L as a prognostic marker among ACS patients and provide valuable insights for clinical practice. To our knowledge, this is the first study of its type in the Arabic World. A multi-center prospective case-control study was conducted in Damascus, Syria, involving 158 participants with different ACS subtypes (STEMI, NSTEMI, UA) and a control group of healthy individuals. Sociodemographic data, medical history, and sCD40L levels were collected. The predictive ability of sCD40L for ACS, STEMI, NSTEMI, and UA was assessed using receiver operating characteristic (ROC) curves. Statistical analysis was performed using IBM SPSS version 25. The study included 58 STEMI, 33 NSTEMI, 36 UA patients, and 30 healthy individuals. The mean age of participants was 55 years (SD 10.7 years). Analysis of sCD40L levels revealed significantly higher concentrations in ACS patients compared to the control group (P < .001). ROC curve analysis demonstrated that sCD40L had a significant predictive ability for ACS, STEMI, and NSTEMI (P < .05), while its predictive value for UA was not statistically significant. This study provides evidence supporting the potential of sCD40L as a prognostic factor in ACS. The elevated levels of sCD40L observed in these subtypes indicate its potential usefulness in risk stratification and predicting adverse cardiovascular events. Further investigations are warranted to establish standardized sCD40L cutoff values and evaluate its clinical implications in the management of ACS patients.

Oncolytic adenovirus encoding decorin and CD40 ligand inhibits tumor growth and liver metastasis via immune activation in murine colorectal tumor model

Colorectal cancer (CRC) is the second common cause of cancer mortality worldwide, and it still lacks effective approaches for relapsed and metastatic CRC. Recently, oncolytic virus has been emerged as a promising immune therapeutic strategy. In this study, we develop a novel oncolytic adenovirus, rAd.mDCN.mCD40L, which drive oncolytic activity by telomerase reverse transcriptase promoter (TERTp). rAd.mDCN.mCD40L expressed both mouse genes of decorin (mDCN) and CD40 ligand (mCD40L), and produced effective cytotoxicity in both human and mouse CRC cells. Moreover, oncolytic adenovirus mediated mDCN over-expression inhibited Met expression in vitro. In CT26 subcutaneous tumor model, intratumorally delivery of oncolytic adenoviruses could inhibit tumor growth and liver metastasis, while mDCN and/or mCD40L armed oncolytic adenoviruses produced much more impressive responses. No obvious toxicity was detected in lung, liver and spleen. Moreover, mDCN and/or mCD40L armed oncolytic adenoviruses altered the immune state to activate anti-tumor responses, including increasing CD8+ T effector cells and CD4+ memory T cells, reducing MDSCs and Tregs in peripheral blood. Furthermore, mDCN and/or mCD40L armed oncolytic adenoviruses mediated mDCN and/or mCD40L expression in tumors, and up-regulated Th1 cytokines and reduced Th2 cytokines in tumors, which will be benefit for remodeling tumor microenvironment. Importantly, rAd.mDCN.mCD40L and rAd.mCD40L prevented tumor liver metastasis much more effectively than rAd.Null and rAd.mDCN. Therefore, rAd.mDCN.mCD40L and rAd.mCD40L are promising approaches for CRC therapy.

A loss of tuning of both pro-coagulant and inflammatory responses in monocytes in patients with preeclampsia

An imbalance between pro- and anti-angiogenesis is one of the leading causes of preeclampsia (PE). Monocytes, known as regulators of angiogenesis during immune responses, cooperate with platelets, but the specifics of these responses during pregnancy remain unclear. In this study, we investigated the relationship between pro-coagulant responses on monocytes [platelet activation marker CD61 as a monocyte-platelet aggregate (MPA), tissue factor (CD142), etc.], inflammatory responses [soluble CD40 ligand (sCD40L), soluble suppression of tumorigenesis-2 (sST2), etc.], and the balance of angiogenesis [soluble Fms-related receptor tyrosine kinase 1/placental growth factor (sFlt-1/PLGF) ratio]. In PE, markers of pro-coagulant and inflammatory responses were higher than those in normal pregnancy (NP). Interestingly, in NP, these markers harmonized with the sFlt-1/PLGF ratio, but not in PE. Furthermore, ex vivo examinations showed that upregulation of CD142 induced by additional platelet activation with adenosine diphosphate was diminished in PE. Conversely, low-dose aspirin, which is used as a preventive treatment for PE, could inhibit the increase of CD61 and sST2 under inflammatory stimuli and platelet activation in NP but not in PE. These results indicate that monocytes in PE upregulate basal activity and lose responsiveness to stimulation. The elevation of pro-coagulant and inflammatory responses may be mitigated by prophylaxis with low-dose aspirin. Therefore, the findings suggesting a loss of tuning of both pro-coagulant and inflammatory responses on monocytes help in understanding the pathology of PE. The harmonization between pro-coagulant responses, inflammatory responses, and angiogenesis may serve as useful indicators for the prediction and preventive treatment of PE.

No effect of surgery on kidney and cardiovascular risk factors in mild primary hyperparathyroidism: secondary analyses from a 10-year randomized controlled trial.

Renal function and the skeleton are classic target organs in primary hyperparathyroidism (PHPT), affected by the chronic course of the disease. Most patients diagnosed today exhibit mild PHPT, characterized by slight hypercalcemia and no or unspecific symptoms. Concerns have been raised that PHPT could promote deteriorating kidney function and increase cardiovascular risk directly. To examine the effect of parathyroidectomy (PTX) on mild PHPT on renal function and markers for bone turnover, cardiovascular disease (CVD), and vascular inflammation. Prospective randomized controlled trial. ClinicalTrials.gov: NCT00522028. Eight Scandinavian referral centers. From 1998 to 2005, 191 patients with mild PHPT were included in Sweden, Norway, and Denmark. Of these 150 were included in the present analyses. Seventy patients were randomized to PTX and 80 to observation without intervention (OBS). e-GFR was calculated based on creatinine and cystatin C. Markers of CVD and systemic inflammation: osteoprotegerin, vascular cell adhesion molecule 1, soluble CD40 ligand, interleukin-1 receptor antagonist, von Willebrand factor. Bone turnover markers: C-terminal telopeptide of type 1 collagen (CTX-1) and serum Procollagen type 1 N-terminal propeptide. No differences in the development of renal function or vascular and systemic inflammation were detected. CTX-1 was lower in PTX after 10 years. Secondary analyses of a randomized controlled trial. PTX does not appear to affect renal function or markers of CVD and vascular inflammation in mild PHPT in a ten-year perspective.

Lipid nanoparticle encapsulation of a Delta spike-CD40L DNA vaccine improves effectiveness against Omicron challenge in Syrian hamsters

The effectiveness of mRNA vaccines largely depends on their lipid nanoparticle (LNP) component. Herein, we investigate the effectiveness of DLin-KC2-DMA (KC2) and SM-102-based LNPs for the intramuscular delivery of a plasmid encoding B.1.617.2 (Delta) spike fused with CD40 ligand. LNP encapsulation of this CD40L-adjuvanted DNA vaccine with either LNP formulation drastically enhanced antibody responses, enabling neutralization of heterologous Omicron variants. The DNA-LNP formulations provided excellent protection from homologous challenge, reducing viral replication, and preventing histopathological changes in the pulmonary tissues. Moreover, theDNA-LNP vaccines maintained a high level of protection against heterologous Omicron BA.5 challenge despite a reduced neutralizing response. In addition, we observed that DNA-LNP vaccination led to the pulmonary downregulation of interferon signaling, interleukin-12 signaling, and macrophage response pathways following SARS-CoV-2 challenge, shedding some light on the mechanisms underlying the prevention of pulmonary injury. These results highlight the potential combination of molecular adjuvants with LNP-based vaccine delivery to induce greater and broader immune responses capable of preventing inflammatory damage and protecting against emerging variants. These findings could be informative for the future design of both DNA and mRNA vaccines.

High-volume hemofiltration does not protect human kidney endothelial and tubular epithelial cells from septic plasma-induced injury

High volume hemofiltration (HVHF) could remove from plasma inflammatory mediators involved in sepsis-associated acute kidney injury (SA-AKI). The IVOIRE trial did not show improvements of outcome and organ dysfunction using HVHF. The aim of this study was to evaluate in vitro the biological effects of plasma of patients treated by HVHF or standard volume hemofiltration (SVHF). We evaluated leukocyte adhesion, apoptosis and functional alterations of endothelial cells (EC) and tubular epithelial cells (TEC). In vitro data were correlated with plasma levels of TNF-α, Fas-Ligand (FasL), CD40-Ligand (CD40L), von Willebrand Factor (vWF) and endothelial-derived microparticles. An experimental model of in vitro hemofiltration using LPS-activated blood was established to assess cytokine mass adsorption during HVHF or SVHF. Plasma concentrations of TNF-ɑ, FasL, CD40L and von Willebrand Factor (vWF) were elevated at the start (d1h0) of both HVHF and SVHF, significantly decreased after 6 h (d1h6), remained stable after 12 h (d1h12) and then newly increased at 48 h (d3h0). Plasma levels of all these molecules were similar between HVHF- and SVHF-treated patients at all time points considered. In addition, the levels of endothelial microparticles remained always elevated, suggesting the presence of a persistent microvascular injury. Plasma from septic patients induced leukocyte adhesion on EC and TEC through up-regulation of adhesion receptors. Moreover, on EC, septic plasma induced a cytotoxic and anti-angiogenic effect. On TEC, septic plasma exerted a direct pro-apoptotic effect via Fas up-regulation and caspase activation, loss of polarity, altered expression of megalin and tight junction molecules with an impaired ability to internalize albumin. The inhibition of plasma-induced cell injury was concomitant to the decrease of TNF-α, Fas-Ligand and CD40-Ligand levels. The protective effect of both HVHF and SVHF was time-limited, since a further increase of circulating mediators and plasma-induced cell injury was observed after 48 h (d3h0). No significant difference of EC/TEC damage were observed using HVHF- or SVHF-treated plasma. The in vitro hemofiltration model confirmed the absence of a significant modulation of cytokine adsorption between HVHF and SVHF. In comparison to SVHF, HVHF did not increase inflammatory cytokine clearance and did not reverse the detrimental effects of septic plasma-induced EC and TEC injury. Further studies using adsorptive membranes are needed to evaluate the potential role of high dose convective therapies in the limitation of the harmful activity of plasma soluble factors involved in SA-AKI.Trial registration IVOIRE randomized clinical trial; ClinicalTrials.gov (NCT00241228) (18/10/2005).

Neu5Gc-mediated high-affinity interaction is dispensable for CD22 cis-ligands to regulate B cell signaling

CD22 (also known as Siglec-2) is an inhibitory receptor expressed in B cells. CD22 specifically recognizes α2,6 sialic acid and interacts with α2,6 sialylated membrane proteins expressed on the same cell (cis-ligands) and those derived from outside of the cell (trans-ligands). Previously, CD22 cis-ligands were shown to regulate the activity of CD22, thereby regulating both BCR ligation-induced signaling and low-level "tonic" signaling in the absence of BCR ligation that regulates the survival and differentiation of B cells. Mouse CD22 prefers Neu5Gc to Neu5Ac thereby binding to α2,6-linked Neu5Gc with high affinity. Although human CD22 binds to a distinct α2,6 sialylated glycan with high affinity, expression of high-affinity ligands is regulated in a conserved and stringent manner. However, how high- versus low-affinity CD22 ligands regulate B cells is poorly understood. Here we demonstrate that the interaction of CD22 with the endogenous ligands enhances BCR ligation-induced signaling but reduces tonic signaling in Cmah-/- mouse B cells deficient in Neu5Gc as well as wild-type B cells. Moreover, Cmah-/- B cells do not show alterations in the phenotypes correlated to tonic signaling. These results indicate that low-affinity interaction of the CD22 cis-ligands with CD22 is sufficient for the regulation of B cell signaling, and suggest that expression of high-affinity CD22 ligands might be involved in the regulation of B cells by competing for the binding of CD22 with exogenous trans-ligands of CD22.