Intratumoral NKT cell accumulation promotes antitumor immunity in pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDA) is a potentially lethal disease lacking effective treatments. Its immunosuppressive tumor microenvironment (TME) allows it to evade host immunosurveillance and limits response to immunotherapy. Here, using the mouse KRT19-deficient (sgKRT19-edited) PDA model, we find that intratumoral accumulation of natural killer T (NKT) cells is required to establish an immunologically active TME. Mechanistically, intratumoral NKT cells facilitate type I interferon (IFN) production to initiate an antitumor adaptive immune response, and orchestrate the intratumoral infiltration of T cells, dendritic cells, natural killer cells, and myeloid-derived suppressor cells. At the molecular level, NKT cells promote the production of type I IFN through the interaction of their CD40L with CD40 on myeloid cells. To evaluate the therapeutic potential of these observations, we find that administration of folinic acid to mice bearing PDA increases NKT cells in the TME and improves their response to anti-PD-1 antibody treatment. In conclusion, NKT cells have an essential role in the immune response to mouse PDA and are potential targets for immunotherapy.

Development of an immunoassay for quantification of soluble human CD40L (CD154) in plasma and serum samples.

When the membrane protein CD40 ligand (CD40L) on activated T cells binds the receptor CD40 on B-cells, it provides a co-stimulatory signal for B cell activation. Dysregulation of the CD40L:CD40 axis is associated with inflammatory and autoimmune diseases. The presence of soluble CD40L (sCD40L) in plasma is implicated in several diseases, from cardiovascular and autoimmune diseases to different types of cancer, and sCD40L has been suggested as a valuable marker of disease. If sCD40L is to be used as a biomarker, being able to precisely measure and quantify the levels of sCD40L in human blood samples is of utmost importance. We demonstrate the development of a sandwich-type time-resolved immunofluorometric assay for quantification of sCD40L in plasma or serum samples. For this, we generate 29 monoclonal anti-CD40L antibodies, and from these, we select the optimal combination of capture antibody and detection antibody. A number of variables were tested: the influence of the type of sample (comparing 3 different blood collection tubes for serum sampling and 4 different types of tubes for plasma sampling), the influence of freeze-thaw cycles, the influence of sampling time during night and day, and the influence of centrifugation of the samples. We found a very similar level of sCD40L in paired EDTA plasma and serum samples. Out of 100 healthy blood donor samples 61 had a level of sCD40L below the detection level of the assay, whereas the remaining 39 samples had ranging levels of sCD40L from 1.14 to 33.14 ng/mL. In summary, we present a time-resolved immunofluorometric assay based on paired monoclonal antibodies, ensuring high specificity, sensitivity, and homogeneity. The Eu3+-based assay additionally provides consistent assay readouts due to the extended decay time not seen in standard enzyme-linked immunosorbent assays. The assay paves the way for specific and consistent quantification of sCD40L in human plasma and serum samples.

Investigation of activation-induced markers (AIM) in porcine T cells by flow cytometry.

Activation-induced markers (AIMs) are frequently analyzed to identify re-activated human memory T cells. However, in pigs the analysis of AIMs is still not very common. Based on available antibodies, we designed a multi-color flow cytometry panel comprising pig-specific or cross-reactive antibodies against CD25, CD69, CD40L (CD154), and ICOS (CD278) combined with lineage/surface markers against CD3, CD4, and CD8α. In addition, we included an antibody against tumor necrosis factor alpha (TNF-α), to study the correlation of AIM expression with the production of this abundant T cell cytokine. The panel was tested on peripheral blood mononuclear cells (PBMCs) stimulated with phorbol 12-myristate 13-acetate (PMA)/ionomycin, Staphylococcus enterotoxin B (SEB) or PBMCs from African swine fever virus (ASFV) convalescent pigs, restimulated with homologous virus. PMA/ionomycin resulted in a massive increase of CD25/CD69 co-expressing T cells of which only a subset produced TNF-α, whereas CD40L expression was largely associated with TNF-α production. SEB stimulation triggered substantially less AIM expression than PMA/ionomycin but also here CD25/CD69 expressing T cells were identified which did not produce TNF-α. In addition, CD40L-single positive and CD25+CD69+CD40L+TNF-α- T cells were identified. In ASFV restimulated T cells TNF-α production was associated with a substantial proportion of AIM expressing T cells but also here ASFV-reactive CD25+CD69+TNF-α- T cells were identified. Within CD8α+ CD4 T cells, several CD25/CD40L/CD69/ICOS defined phenotypes expanded significantly after ASFV restimulation. Hence, the combination of AIMs tested will allow the identification of primed T cells beyond the commonly used cytokine panels, improving capabilities to identify the full breadth of antigen-specific T cells in pigs.

Humoral responses are enhanced by facilitating B cell viability by Fcrl5 overexpression in B cells.

B cell initial activity is regulated through a balance of activation and suppression mediated by regulatory molecules expressed in B cells; however, the molecular mechanisms underlying this process remain incompletely understood. In this study, we investigated the function of the Fc receptor-like (Fcrl) family molecule Fcrl5, which is constitutively expressed on naïve B cells, in humoral immune responses. Our study demonstrated that B cell-specific overexpression of Fcrl5 enhanced antibody (Ab) production in both T cell-independent type 1 (TI1) and T cell-dependent (TD) responses. Additionally, it promoted effector B cell formation under competitive conditions in TD responses. Mechanistically, in vitro ligation of Fcrl5 by agonistic Abs reduced cell death and enhanced proliferation in lipopolysaccharide (LPS)-stimulated B cells. In the presence of anti-CD40 Abs and IL-5, the Fcrl5 ligation not only suppressed cell death but also enhanced differentiation into plasma cells. These findings reveal a novel role of Fcrl5 in promoting humoral immune responses by enhancing B cell viability and plasma cell differentiation.

Pneumocystis murina lesions in lungs of experimentally infected Cd40l-/- mice.

The Cd40l-/- mouse is a well-established model of X-linked hyper-immunoglobulin M (IgM) syndrome, an immunodeficiency disorder of human beings characterized by the lack of expression of the CD40 ligand (CD40L) on activated T-cells, predisposing to infections with opportunistic pathogens like Pneumocystis jirovecii. The aim of our study was to describe the pulmonary lesions in Cd40l-/- mice experimentally infected with Pneumocystis murina, in comparison with naturally infected severe combined immunodeficient (SCID) mice. Formalin-fixed paraffin-embedded lungs from 26 Cd40l-/-, 11 SCID, and 5 uninfected Cd40l-/- mice were examined by histology and immunohistochemistry for the presence of the pathogen and for leukocyte populations (CD3, CD4, CD45R/B220, CD8a, Iba-1, Ly-6G, CD206, MHC II, and NKp46/NCR1). Infection was confirmed by immunohistochemistry in 18/26 (69%) Cd40l-/- mice and in 11/11 (100%) SCID mice. Fourteen out of 26 (54%) Cd40l-/- mice had interstitial pneumonia. Twenty-three out of 26 (88%) Cd40l-/- mice had peribronchiolar/perivascular lymphoplasmacytic infiltrates, rich in B-cells and Mott cells. Acidophilic macrophage pneumonia was additionally found in 20/26 (77%) Cd40l-/- mice. Only 4/11 (36%) SCID mice had interstitial pneumonia, but no peribronchiolar/perivascular infiltrates or acidophilic macrophage pneumonia were observed in this strain. This study represents the first description of pulmonary histopathological lesions in Cd40l-/- mice infected with P. murina. We speculate that the singular characteristics of the inflammatory infiltrates observed in Cd40l-/- mice could be explained by the specific immune phenotype of the model.

Evaluation of a Combinatorial Immunotherapy Regimen That Can Cure Mice Bearing MYCN-Driven High-Risk Neuroblastoma That Resists Current Clinical Therapy.

Background: Incorporating GD2-targeting monoclonal antibody into post-consolidation maintenance therapy has improved survival for children with high-risk neuroblastoma. However, ~50% of patients do not respond to, or relapse following, initial treatment. Here, we evaluated additional anti-GD2-based immunotherapy to better treat high-risk neuroblastoma in mice to develop a regimen for patients with therapy-resistant neuroblastoma. Methods: We determined the components of a combined regimen needed to cure mice of established MYCN-amplified, GD2-expressing, murine 9464D-GD2 neuroblastomas. Results: First, we demonstrate that 9464D-GD2 is nonresponsive to a preferred salvage regimen: anti-GD2 with temozolomide and irinotecan. Second, we have previously shown that adding agonist anti-CD40 mAb and CpG to a regimen of radiotherapy, anti-GD2/IL2 immunocytokine and anti-CTLA-4, cured a substantial fraction of mice bearing small 9464D-GD2 tumors; here, we further characterize this regimen by showing that radiotherapy and hu14.18-IL2 are necessary components, while anti-CTLA-4, anti-CD40, or CpG can individually be removed, and CpG and anti-CTLA-4 can be removed together, while maintaining efficacy. Conclusions: We have developed and characterized a regimen that can cure mice of a high-risk neuroblastoma that is refractory to the current clinical regimen for relapsed/refractory disease. Ongoing preclinical work is directed towards ways to potentially translate these findings to a regimen appropriate for clinical testing.

CD40L-Activated DC Promotes Th17 Differentiation and Inhibits Th2 Differentiation in Sepsis-Induced Lung Injury via cGAS-STING Signaling.

Immune hemostasis due to an infection plays a vital role in sepsis-induced multiple organ dysfunction. Dendritic cells (DC) and T helper (Th) cells are the key members of the immune system maintaining immune homeostasis. This study aimed to explore the effect and mechanism of CD40L on the activation of DC and activated DC-induced Th2/Th17 differentiation. A CD40L knockout and cecal ligation and puncture (CLP) mouse model was established via cecal ligation. HE staining was used to evaluate the pathological changes. The gene expressions were studied using quantitative real-time polymerase chain reaction (qRT-PCR), while a transwell system was used to perform the co-culture of DC and T-cells. Flow cytometry was performed to detect the subtype of T and DC cells. ELISA was used to assess the amount of inflammatory factors. CD40L was highly expressed in the plasma of CLP mice. Knock out of CD40L inhibited the activation of DC cell and Th17 differentiation while promoting the Th2 differentiation. The mechanistic investigations revealed that CD40L promoted the activation of cGAS-STING pathway. Rescue experiments indicated that CD40L mediated DC activation via cGAS-STING signaling. Moreover, co-culturing of CD and CD+4 T-cells demonstrated that silencing of CD40L in DC suppressed the DC activation and inhibited Th17 differentiation while promoting Th2 differentiation. These findings revealed a relationship between CD40L, DC activation, and Th2/Th17 differentiation balance in sepsis-induced acute lung injury for the first time. These findings are envisaged to provide novel molecular targets for sepsis-induced lung injury treatment.

The engineered agonistic anti-CD40 antibody potentiates the antitumor effects of ß-glucan by resetting TAMs.

Anti-CD40 antibodies (Abs) have been shown to induce antitumor T-cell responses. We reported that the engineered agonistic anti-CD40 Ab (5C11, IgG4 isotype) recognized human CD40 antigen expressed on a human B lymphoblastoid cell line as well as on splenic cells isolated from humanized CD40 mice. Of note, a single high dosage of 5C11 was able to prohibit tumor growth in parallel with an increase in the population of infiltrated CD8+ T cells. Furthermore, the antitumor effects of 5C11 were enhanced in the presence of ß-glucan along with an increase in the population of infiltrated CD8+ T cells. In addition, the numbers of CD86+ TAMs and neutrophils were elevated in the combination of 5C11 and ß-glucan compared with either 5C11 or ß-glucan alone. Furthermore, the abundance of Faecalibaculum, one of the probiotics critical for tumor suppression, was obviously increased in the combination of 5C11 and ß-glucan-treated mice. These data reveal a novel mechanism of tumor suppression upon the combination treatment of 5C11 and ß-glucan and propose that the combination treatment of agonistic anti-human CD40 antibody 5C11 and ß-glucan could be a promising therapeutic strategy for cancer patients.

Engineered Bacteriophage-Based In Situ Vaccine Remodels a Tumor Microenvironment and Elicits Potent Antitumor Immunity.

In situ vaccines (ISVs) utilize the localized delivery of chemotherapeutic agents or radiotherapy to stimulate the release of endogenous antigens from tumors, thereby eliciting systemic and persistent immune activation. Recently, a bioinspired ISV strategy has attracted tremendous attention due to its features such as an immune adjuvant effect and genetic plasticity. M13 bacteriophages are natural nanomaterials with intrinsic immunogenicity, genetic flexibility, and cost-effectiveness for large-scale production, demonstrating the potential for application in cancer vaccines. In this study, we propose an ISV based on the engineered M13 bacteriophage targeting CD40 (M13CD40) for dendritic cell (DC)-targeted immune stimulation, named H-GM-M13CD40. We induce immunogenic cell death and release tumor antigens through local delivery of (S)-10-hydroxycamptothecin (HCPT), followed by intratumoral injection of granulocyte-macrophage colony stimulating factor (GM-CSF) and M13CD40 to enhance DC recruitment and activation. We demonstrate that this ISV strategy can result in significant accumulation and activation of DCs at the tumor site, reversing the immunosuppressive tumor microenvironment. In addition, H-GM-M13CD40 can synergize with the PD-1 blockade and induce abscopal effects in cold tumor models. Overall, our study verifies the immunogenicity of the engineered M13CD40 bacteriophage and provides a proof of concept that the engineered M13CD40 phage can function as an adjuvant for ISVs.

Next-generation CD40 agonists for cancer immunotherapy.

INTRODUCTION: There is a need for new therapies that can enhance response rates and broaden the number of cancer indications where immunotherapies provide clinical benefit. CD40 targeting therapies provide an opportunity to meet this need by promoting priming of tumor-specific T cells and reverting the suppressive tumor microenvironment. This is supported by emerging clinical evidence demonstrating the benefits of immunotherapy with CD40 antibodies in combination with standard of care chemotherapy. AREAS COVERED: This review is focused on the coming wave of next-generation CD40 agonists aiming to improve efficacy and safety, using new approaches and formats beyond monospecific antibodies. Further, the current understanding of the role of different CD40 expressing immune cell populations in the tumor microenvironment is reviewed. EXPERT OPINION: There are multiple promising next-generation approaches beyond monospecific antibodies targeting CD40 in immuno-oncology. Enhancing efficacy is the most important driver for this development, and approaches that maximize the ability of CD40 to both remodel the tumor microenvironment and boost the anti-tumor T cell response provide great opportunities to benefit cancer patients. Enhanced understanding of the role of different CD40 expressing immune cells in the tumor microenvironment may facilitate more efficient clinical development of these compounds.

Tfh cell-derived small extracellular vesicles exacerbate the severity of collagen-induced arthritis by enhancing B-cell responses.

Soluble components secreted by Tfh cells are critical for the germinal center responses. In this study, we investigated whether Tfh cells could regulate the B-cell response by releasing small extracellular vesicles (sEVs). Our results showed that Tfh cells promote B-cell differentiation and antibody production through sEVs and that CD40L plays a crucial role in Tfh-sEVs function. In addition, increased Tfh-sEVs were found in mice with collagen-induced arthritis (CIA). Adoptive transfer of Tfh cells significantly exacerbated the severity of CIA; however, the effect of Tfh cells on exacerbating the CIA process was significantly diminished after inhibiting sEVs secretion. Moreover, the levels of plasma Tfh-like-sEVs and CD40L expression on Tfh-like-sEVs in RA patients were significantly higher than those in healthy subjects. In summary, Tfh cell-derived sEVs can enhance the B-cell response, and exacerbate the procession of autoimmune arthritis.

Efficacy of IFN-γ, sCD40L, and Poly(I:C) Treated Bone Marrow-Derived Macrophages in Murine Mammary Carcinoma.

INTRODUCTION: Here, we explored methods to generate anti-tumor bone marrow-derived macrophages (BMDM) and how delivery of the BMDM at early tumor sites could impact disease progression. METHODS: BMDM treated with IFN-γ, sCD40L, poly(I:C), and a combination of the three were assessed. RESULTS: Treatment with sCD40L had no significant impact on the BMDM. Treating BMDM with IFN-γ impacted IL-1ß, MHC Class II, and CD80 expression. While poly(I:C) treatment had a greater impact on the BMDM than IFN-γ when assessed by the in vitro assays, the BMDM treated with poly (I:C) had mixed results in vivo where they decreased growth of the EMT6 tumor, did not impact growth of the 168 tumor, and enhanced growth of the 4T1 tumor. The combination of poly(I:C), IFN-γ, and sCD40L had the greatest impact on the BMDM in vitro and in vivo. Treatment with all three agonists resulted in increased IL-1ß, TNF-α, and IL-12 expression, decreased expression of arginase and mrc, increased phagocytic activity, nitrite production, and MHC Class II and CD80 expression, and significantly impacted growth of the EMT6 and 168 murine mammary carcinoma models. DISCUSSION: Collectively, these data show that treating BMDM with poly(I:C), IFN-γ, and sCD40L generates BMDM with more consistent anti-tumor activity than BMDM generated with the individual agonists.

Bariatric Surgery Improves Serum CD40L Levels as a Predictor of Cardiovascular Risk: Systematic Review and Meta-analysis.

CD40 and its ligand have been recently implicated in the pathogenesis of cardiovascular disease (CVD). This meta-analysis examined the effect of bariatric surgery in reducing circulating CD40L levels. A systematic review was performed using Embase, Google Scholar, PubMed, Scopus, and Web of Science. The meta-analysis was provided by Comprehensive Meta-Analysis (CMA) V4 software. The overall effect size was detected by a random-effects meta-analysis and the leave-one-out approach. Random-effects meta-analysis of 7 studies including 191 subjects showed a significant reduction in CD40L after bariatric surgery (standardized mean difference (SMD), - 0.531; 95% CI, - 0.981, - 0.082; p = 0.021; I2, 87.00). Circulating levels of CD40L are decreased after bariatric surgery which may represent a mechanism for improvement of metabolic profile.

A novel hemizygous CD40L mutation of X-linked hyper IgM syndromes and compound heterozygous DOCK8 mutations of hyper IgE syndromes in two Chinese families.

X-linked hyper-immunoglobulin M (X-HIGM) syndrome and autosomal recessive hyper-immunoglobulin E syndrome (HIES) are rare inborn errors of immunity characterized by recurrent infections due to immune system impairment. In this study, we identified a novel hemizygous CD40 ligand (CD40L) mutation and compound heterozygous dedicator of cytokinesis-8 (DOCK8) mutations in two Han Chinese families with X-HIGM and HIES, respectively. We aimed to investigate the association between their genotypes and phenotypes. Genomic DNA was extracted from peripheral blood samples obtained from the families. Whole exome sequencing and Sanger sequencing were performed to identify and verify pathogenic variants in the two families. Clinical analyses of the probands were also performed. A novel hemizygous mutation of CD40L in exon 2 (c.257delA) was identified in the first proband, resulting in the substitution of glycine with glutamic acid at codon 86 of the protein. This leads to premature termination of translation at downstream codon 9 (p.E86Gfs*9). Sanger sequencing confirmed that the variant was inherited from the mother. The second proband carried two novel compound heterozygous mutations in DOCK8: one at exon 14 (c.1546C > G) inherited from the father, and the other at intron 41 (c.5355 + 6C > T; splicing) inherited from the mother. This study enhances our understanding of the pathogenetic mutation spectrum of CD40L and DOCK8 genes, facilitating the prenatal diagnosis of X-HIGM and HIES and enabling timely treatment of patients.

Crystal structures of human CD40 in complex with monoclonal antibodies dacetuzumab and bleselumab.

CD40 is a member of the tumor necrosis factor receptor superfamily, and it is widely expressed on immune and non-immune cell types. The interaction between CD40 and the CD40 ligand (CD40L) plays an essential function in signaling, and the CD40/CD40L complex works as an immune checkpoint molecule. CD40 has become a therapeutic target, and a variety of agonistic/antagonistic anti-CD40 monoclonal antibodies (mAbs) have been developed. To better understand the mode of action of anti-CD40 mAbs, we determined the X-ray crystal structures of dacetuzumab (agonist) and bleselumab (antagonist) in complex with the extracellular domain of human CD40, respectively. The structure reveals that dacetuzumab binds to CD40 on the top of cysteine-rich domain 1 (CRD1), which is the domain most distant from the cell surface, and it does not compete with CD40L binding. The binding interface of bleselumab spread between CRD2 and CRD1, overlapping with the binding surface of the ligand. Our results offer important insights for future structural and functional studies of CD40 and provide clues to understanding the mechanism of biological response. These data can be applied to developing new strategies for designing antibodies with more therapeutic efficacy.

Fcγ-Receptor-Independent Controlled Activation of CD40 Canonical Signaling by Novel Therapeutic Antibodies for Cancer Therapy.

The activation of CD40-mediated signaling in antigen-presenting cells is a promising therapeutic strategy to promote immune responses against tumors. Most agonistic anti-CD40 antibodies currently in development require the Fcγ-receptor (FcγR)-mediated crosslinking of CD40 molecules for a meaningful activation of CD40 signaling but have limitations due to dose-limiting toxicities. Here we describe the identification of CD40 antibodies which strongly stimulate antigen-presenting cells in an entirely FcγR-independent manner. These Fc-silenced anti-CD40 antibodies induce an efficient upregulation of costimulatory receptors and cytokine release by dendritic cells. Finally, the most active identified anti-CD40 antibody shows activity in humanized mice. More importantly, there are no signs of obvious toxicities. These studies thus demonstrate the potent activation of antigen-presenting cells with anti-CD40 antibodies lacking FcγR-binding activity and open the possibility for an efficacious and safe combination therapy for cancer patients.

Role of inflammatory signaling pathways involving the CD40-CD40L-TRAF cascade in diabetes and hypertension-insights from animal and human studies.

CD40L-CD40-TRAF signaling plays a role in atherosclerosis progression and affects the pathogenesis of coronary heart disease (CHD). We tested the hypothesis that CD40L-CD40-TRAF signaling is a potential therapeutic target in hyperlipidemia, diabetes, and hypertension. In mouse models of hyperlipidemia plus diabetes (db/db mice) or hypertension (1 mg/kg/d angiotensin-II for 7 days), TRAF6 inhibitor treatment (2.5 mg/kg/d for 7 or 14 days) normalized markers of oxidative stress and inflammation. As diabetes and hypertension are important comorbidities aggravating CHD, we explored whether the CD40L-CD40-TRAF signaling cascade and their associated inflammatory pathways are expressed in CHD patients suffering from comorbidities. Therefore, we analyzed vascular bypass material (aorta or internal mammary artery) and plasma from patients with CHD with diabetes and/or hypertension. Our Olink targeted plasma proteomic analysis using the IMMUNO-ONCOLOGY panel revealed a pattern of step-wise increase for 13/92 markers of low-grade inflammation with significant changes. CD40L or CD40 significantly correlated with 38 or 56 other inflammatory targets. In addition, specific gene clusters that correlate with the comorbidities were identified in isolated aortic mRNA of CHD patients through RNA-sequencing. These signaling clusters comprised CD40L-CD40-TRAF, immune system, hemostasis, muscle contraction, metabolism of lipids, developmental biology, and apoptosis. Finally, immunological analysis revealed key markers correlated with comorbidities in CHD patients, such as CD40L, NOX2, CD68, and 3-nitrotyrosine. These data indicate that comorbidities increase inflammatory pathways in CHD, and targeting these pathways will be beneficial in reducing cardiovascular events in CHD patients with comorbidities.

Investigating the Use of a Liquid Immunogenic Fiducial Eluter Biomaterial in Cervical Cancer Treatment.

Globally, cervical cancer is the fourth leading cancer among women and is dominant in resource-poor settings in its occurrence and mortality. This study focuses on developing liquid immunogenic fiducial eluter (LIFE) Biomaterial with components that include biodegradable polymers, nanoparticles, and an immunoadjuvant. LIFE Biomaterial is designed to provide image guidance during radiotherapy similar to clinically used liquid fiducials while enhancing therapeutic efficacy for advanced cervical cancer. C57BL6 mice were used to grow subcutaneous tumors on bilateral flanks. The tumor on one flank was then treated using LIFE Biomaterial prepared with the immunoadjuvant anti-CD40, with/without radiotherapy at 6 Gy. Computed tomography (CT) and magnetic resonance (MR) imaging visibility were also evaluated in human cadavers. A pharmacodynamics study was also conducted to assess the safety of LIFE Biomaterial in healthy C57BL6 female mice. Results showed that LIFE Biomaterial could provide both CT and MR imaging contrast over time. Inhibition in tumor growth and prolonged significant survival (* p < 0.05) were consistently observed for groups treated with the combination of radiotherapy and LIFE Biomaterial, highlighting the potential for this strategy. Minimal toxicity was observed for healthy mice treated with LIFE Biomaterial with/without anti-CD40 in comparison to non-treated cohorts. The results demonstrate promise for the further development and clinical translation of this approach to enhance the survival and quality of life of patients with advanced cervical cancer.

A vaccine targeting antigen-presenting cells through CD40 induces protective immunity against Nipah disease.

Nipah virus (NiV) has been recently ranked by the World Health Organization as being among the top eight emerging pathogens likely to cause major epidemics, whereas no therapeutics or vaccines have yet been approved. We report a method to deliver immunogenic epitopes from NiV through the targeting of the CD40 receptor of antigen-presenting cells by fusing a selected humanized anti-CD40 monoclonal antibody to the Nipah glycoprotein with conserved NiV fusion and nucleocapsid peptides. In the African green monkey model, CD40.NiV induces specific immunoglobulin A (IgA) and IgG as well as cross-neutralizing responses against circulating NiV strains and Hendra virus and T cell responses. Challenge experiments using a NiV-B strain demonstrate the high protective efficacy of the vaccine, with all vaccinated animals surviving and showing no significant clinical signs or virus replication, suggesting that the CD40.NiV vaccine conferred sterilizing immunity. Overall, results obtained with the CD40.NiV vaccine are highly promising in terms of the breadth and efficacy against NiV.