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International Journal of Infectious... Jun 2024This study aimed to investigate the prevalence of orthoebolavirus antibodies in Madina Oula, a non-epidemic rural area in Guinea, in 2022.
OBJECTIVES
This study aimed to investigate the prevalence of orthoebolavirus antibodies in Madina Oula, a non-epidemic rural area in Guinea, in 2022.
METHODS
A cross-sectional study conducted from March 14 to April 3, 2022, involved recording household and socio-demographic characteristics, lifestyle data, and collecting dried blood spots (DBS) from 878 individuals in 235 households. DBS were tested using multiplex serology to detect antibodies to different orthoebolaviruses: Ebola (EBOV), Bundibugyo (BDBV), Sudan (SUDV), Reston (RESTV) and Bombali (BOMV). Seroprevalence was estimated with a 95% confidence interval (CI) and Z-test was performed to compare seropositivity between in children under 15 and those over 15. Household and participant characteristics were analyzed using descriptive statistic, and socio-historical conditions were discussed.
RESULTS
Serological analysis conducted in 2022 on 878 participants revealed varying reactivity to orthoebolavirus antigens, notably with GP antigens, particularly glycoprotein SUDV (16%). Twenty-one samples exhibited reactivity with at least two antigens, with a median age of 27 years (interquartile range = 10.00 - 35.00) ranging from 2 to 80 years. There is no significant difference between seropositivity in children under 15 (2.86%) and those over 15 (2.14%). Antibody presence varied per village, with the highest prevalence observed in Ouassou and Dar-es-Salam.
CONCLUSION
Serological data in a region unaffected by recent Ebola outbreaks indicate possible orthoebolavirus endemicity, emphasizing the need for preparedness against known or novel orthoebolaviruses with potential cross-reactivity.
PubMed: 38908818
DOI: 10.1016/j.ijid.2024.107129 -
Malnutrition disrupts adaptive immunity during visceral leishmaniasis by enhancing IL-10 production.BioRxiv : the Preprint Server For... Jun 2024Protein-energy malnutrition (PEM) is a risk factor for developing visceral leishmaniasis (VL). However, the impact on adaptive immunity during infection is unknown. To...
UNLABELLED
Protein-energy malnutrition (PEM) is a risk factor for developing visceral leishmaniasis (VL). However, the impact on adaptive immunity during infection is unknown. To study the effect of malnutrition on chronic VL, we used a polynutrient-deficient diet (deficient protein, energy, zinc, and iron), which mimics moderate human malnutrition, followed by infection. The polynutrient-deficient diet leads to growth stunting and reduced mass of visceral organs. Malnourished-infected mice harbored more parasites in the spleen and liver, had a reduced number of T lymphocytes, reduced production of IFN-γ by T cells, and exhibited enhanced IL-10 production. To test whether IL-10 blockade would lessen disease in the malnourished mice, we treated infected mice with monoclonal antibody α-IL-10R. α-IL-10R treatment reduced the parasite number of malnourished mice, restored the number of T cells producing IFN-γ, and enhanced hepatic granuloma formation. Our results indicate that malnutrition increases VL susceptibility due to a defective IFN-γ-mediated immunity attributable to increased IL-10 production.
AUTHOR SUMMARY
Malnutrition contributes to the development of VL. Despite the advances regarding this association, how malnutrition affects the adaptive immune mechanisms in VL is still unclear. We found that malnutrition disrupts the ability to control parasite replication in the spleen and liver in VL due to defective IFN-γ-mediated immunity, reduced hepatic granuloma formation, and enhanced IL-10 production. Blocking IL-10R signaling restored the protective mechanisms to control parasite replication in the malnourished mice without interfering with the undernutrition state. Thus, we demonstrate that malnutrition disrupts the adaptive immunity against VL due to an aberrant IL-10 production. Understanding the association between malnutrition and VL will provide insights into therapeutic approaches.
PubMed: 38895324
DOI: 10.1101/2024.06.06.597776 -
Cancers May 2024The disialoganglioside, GD2, is a promising therapeutic target due to its overexpression in certain tumors, particularly neuroblastoma (NB), with limited expression in...
The disialoganglioside, GD2, is a promising therapeutic target due to its overexpression in certain tumors, particularly neuroblastoma (NB), with limited expression in normal tissues. Despite progress, the intricate mechanisms of action and the full spectrum of the direct cellular responses to anti-GD2 antibodies remain incompletely understood. In this study, we examined the direct cytotoxic effects of the humanized anti-GD2 antibody hu14.18K322A (hu14) on NB cell lines, by exploring the associated cell-death pathways. Additionally, we assessed the synergy between hu14 and conventional induction chemotherapy drugs. Our results revealed that hu14 treatment induced direct cytotoxic effects in CHLA15 and SK-N-BE1 cell lines, with a pronounced impact on proliferation and colony formation. Apoptosis emerged as the predominant cell-death pathway triggered by hu14. Furthermore, we saw a reduction in GD2 surface expression in response to hu14 treatment. Hu14 demonstrated synergy with induction chemotherapy drugs with alterations in GD2 expression. Our comprehensive investigation provides valuable insights into the multifaceted effects of hu14 on NB cells, shedding light on its direct cytotoxicity, cell-death pathways, and interactions with induction chemotherapy drugs. This study contributes to the evolving understanding of anti-GD2 antibody therapy and its potential synergies with conventional treatments in the context of NB.
PubMed: 38893185
DOI: 10.3390/cancers16112064 -
International Journal of Molecular... May 2024Understanding the factors which control endothelial cell (EC) function and angiogenesis is crucial for developing the horse as a disease model, but equine ECs remain...
Understanding the factors which control endothelial cell (EC) function and angiogenesis is crucial for developing the horse as a disease model, but equine ECs remain poorly studied. In this study, we have optimised methods for the isolation and culture of equine aortic endothelial cells (EAoECs) and characterised their angiogenic functions in vitro. Mechanical dissociation, followed by magnetic purification using an anti-VE-cadherin antibody, resulted in EC-enriched cultures suitable for further study. Fibroblast growth factor 2 (FGF2) increased the EAoEC proliferation rate and stimulated scratch wound closure and tube formation by EAoECs on the extracellular matrix. Pharmacological inhibitors of FGF receptor 1 (FGFR1) (SU5402) or mitogen-activated protein kinase (MEK) (PD184352) blocked FGF2-induced extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation and functional responses, suggesting that these are dependent on FGFR1/MEK-ERK signalling. In marked contrast, vascular endothelial growth factor-A (VEGF-A) had no effect on EAoEC proliferation, migration, or tubulogenesis and did not promote ERK1/2 phosphorylation, indicating a lack of sensitivity to this classical pro-angiogenic growth factor. Gene expression analysis showed that unlike human ECs, FGFR1 is expressed by EAoECs at a much higher level than both VEGF receptor (VEGFR)1 and VEGFR2. These results suggest a predominant role for FGF2 versus VEGF-A in controlling the angiogenic functions of equine ECs. Collectively, our novel data provide a sound basis for studying angiogenic processes in horses and lay the foundations for comparative studies of EC biology in horses versus humans.
Topics: Animals; Fibroblast Growth Factor 2; Horses; Endothelial Cells; Neovascularization, Physiologic; Vascular Endothelial Growth Factor A; Cell Proliferation; Receptor, Fibroblast Growth Factor, Type 1; Cell Movement; Cells, Cultured; MAP Kinase Signaling System; Phosphorylation
PubMed: 38892205
DOI: 10.3390/ijms25116017 -
International Journal of Molecular... May 2024Pertuzumab (Perjeta), a humanized antibody binding to the dimerization arm of HER2 (Human epidermal growth factor receptor-2), has failed as a monotherapy agent in HER2...
Pertuzumab (Perjeta), a humanized antibody binding to the dimerization arm of HER2 (Human epidermal growth factor receptor-2), has failed as a monotherapy agent in HER2 overexpressing malignancies. Since the molecular interaction of HER2 with ligand-bound EGFR (epidermal growth factor receptor) has been implied in mitogenic signaling and malignant proliferation, we hypothesized that this interaction, rather than HER2 expression and oligomerization alone, could be a potential molecular target and predictor of the efficacy of pertuzumab treatment. Therefore, we investigated static and dynamic interactions between HER2 and EGFR molecules upon EGF stimulus in the presence and absence of pertuzumab in HER2+ EGFR+ SK-BR-3 breast tumor cells using Förster resonance energy transfer (FRET) microscopy and fluorescence correlation and cross-correlation spectroscopy (FCS/FCCS). The consequential activation of signaling and changes in cell proliferation were measured by Western blotting and MTT assay. The autocorrelation functions of HER2 diffusion were best fitted by a three-component model corrected for triplet formation, and among these components the slowly diffusing membrane component revealed aggregation induced by EGFR ligand binding, as evidenced by photon-counting histograms and co-diffusing fractions. This aggregation has efficiently been prevented by pertuzumab treatment, which also inhibited the post-stimulus interaction of EGFR and HER2, as monitored by changes in FRET efficiency. Overall, the data demonstrated that pertuzumab, by hindering post-stimulus interaction between EGFR and HER2, inhibits EGFR-evoked HER2 aggregation and phosphorylation and leads to a dose-dependent decrease in cell proliferation, particularly when higher amounts of EGF are present. Consequently, we propose that EGFR expression on HER2-positive tumors could be taken into consideration as a potential biomarker when predicting the outcome of pertuzumab treatment.
Topics: Humans; Antibodies, Monoclonal, Humanized; ErbB Receptors; Receptor, ErbB-2; Cell Line, Tumor; Signal Transduction; Female; Cell Proliferation; Breast Neoplasms; Fluorescence Resonance Energy Transfer; Transcriptional Activation; Antineoplastic Agents, Immunological
PubMed: 38892166
DOI: 10.3390/ijms25115978 -
Cancer Medicine Jun 2024Therapy-induced senescent cancer and stromal cells secrete cytokines and growth factors to promote tumor progression. Therefore, senescent cells may be novel targets for...
INTRODUCTION
Therapy-induced senescent cancer and stromal cells secrete cytokines and growth factors to promote tumor progression. Therefore, senescent cells may be novel targets for tumor treatment. Near-infrared photoimmunotherapy (NIR-PIT) is a highly tumor-selective therapy that employs conjugates of a molecular-targeting antibody and photoabsorber. Thus, NIR-PIT has the potential to be applied as a novel senolytic therapy. This study aims to investigate the efficacy of NIR-PIT treatment on senescent cancer and stromal cells.
METHODS
Two cancer cell lines (human lung adenocarcinoma A549 cells and human pancreatic cancer MIA PaCa-2 cells) and two normal cell lines (mouse fibroblast transfected with human epidermal growth factor receptor 2 [HER2] cells and human fibroblast WI38 cells) were used. The cytotoxicity of NIR-PIT was evaluated using anti-epidermal growth factor receptor (EGFR) antibody panitumumab and anti-HER2 antibody transtuzumab.
RESULTS
Cellular senescence was induced in A549 and MIA PaCa-2 cells by 10 Gy γ-irradiation. The up-regulation of cellular senescence markers and characteristic morphological changes in senescent cells, including enlargement, flattening, and multinucleation, were observed in cancer cells after 5 days of γ-irradiation. Then, NIR-PIT targeting EGFR was performed on these senescent cancer cells. The NIR-PIT induced morphological changes, including bleb formation, swelling, and the inflow of extracellular fluid, and induced a significant decrease in cellular viability. These results suggested that NIR-PIT may induce cytotoxicity using the same mechanism in senescent cancer cells. In addition, similar morphological changes were also induced in radiation-induced senescent 3T3-HER2 fibroblasts by NIR-PIT targeting human epidermal growth factor receptor 2.
CONCLUSION
NIR-PIT eliminates both senescent cancer and stromal cells in vitro suggesting it may be a novel strategy for tumor treatment.
Topics: Humans; Cellular Senescence; Animals; Mice; Immunotherapy; Stromal Cells; Phototherapy; ErbB Receptors; Cell Line, Tumor; Infrared Rays; Receptor, ErbB-2; Lung Neoplasms; Trastuzumab; Panitumumab; A549 Cells; Gamma Rays
PubMed: 38888415
DOI: 10.1002/cam4.7381 -
Acta Neuropathologica Communications Jun 2024Filaments made of residues 120-254 of transmembrane protein 106B (TMEM106B) form in an age-dependent manner and can be extracted from the brains of neurologically normal...
Filaments made of residues 120-254 of transmembrane protein 106B (TMEM106B) form in an age-dependent manner and can be extracted from the brains of neurologically normal individuals and those of subjects with a variety of neurodegenerative diseases. TMEM106B filament formation requires cleavage at residue 120 of the 274 amino acid protein; at present, it is not known if residues 255-274 form the fuzzy coat of TMEM106B filaments. Here we show that a second cleavage appears likely, based on staining with an antibody raised against residues 263-274 of TMEM106B. We also show that besides the brain TMEM106B inclusions form in dorsal root ganglia and spinal cord, where they were mostly found in non-neuronal cells. We confirm that in the brain, inclusions were most abundant in astrocytes. No inclusions were detected in heart, liver, spleen or hilar lymph nodes. Based on their staining with luminescent conjugated oligothiophenes, we confirm that TMEM106B inclusions are amyloids. By in situ immunoelectron microscopy, TMEM106B assemblies were often found in structures resembling endosomes and lysosomes.
Topics: Membrane Proteins; Humans; Nerve Tissue Proteins; Spinal Cord; Amyloid; Ganglia, Spinal; Brain; Male; Female; Peripheral Nervous System; Aged; Animals
PubMed: 38886865
DOI: 10.1186/s40478-024-01813-z -
Research Square Jun 2024While CD40 agonism is an attractive approach for activating antigen-presenting cells and initiating antitumor responses, previous attempts have encountered limited...
While CD40 agonism is an attractive approach for activating antigen-presenting cells and initiating antitumor responses, previous attempts have encountered limited clinical efficacy coupled with toxicity. We previously demonstrated that interactions between the antibody Fc domain and the inhibitory receptor FcγRIIB are critical for enhanced antitumor activity. Here, we present the results of a phase 1 study on intratumoral administration of an anti-CD40 agonistic antibody (2141-V11) Fc-engineered to enhance FcγRIIB binding. Primary endpoints included safety, maximum tolerated dose (MTD), and recommended phase 2 dose. Secondary objectives included preliminary clinical activity and correlative studies from biospecimens. 2141-V11 was well-tolerated without dose-limiting toxicities and MTD was not reached. In ten evaluable patients with metastatic cancer, the overall response rate was 20%, with complete responses in two patients (melanoma and breast carcinoma) and stable disease in six patients. 2141-V11 induced tumor regression in injected and non-injected lesions, with increased leukocyte infiltration and tertiary lymphoid structures (TLS) formation in post-treatment biopsies. In a humanized mouse model for CD40 and FcγRs, 2141-V11 induced TLS formation in mice bearing orthotopic breast carcinoma, correlating with local and abscopal antitumor effects, systemic immune activation, and immune memory. These findings support the safety and efficacy of 2141-V11, warranting phase 2 studies and suggesting a unique mechanism of action for this Fc-enhanced immunotherapy (NCT04059588).
PubMed: 38883779
DOI: 10.21203/rs.3.rs-4244833/v1 -
NPJ Vaccines Jun 2024Alzheimer's disease (AD) and related tauopathies are associated with pathological tau protein aggregation, which plays an important role in neurofibrillary degeneration...
Alzheimer's disease (AD) and related tauopathies are associated with pathological tau protein aggregation, which plays an important role in neurofibrillary degeneration and dementia. Targeted immunotherapy to eliminate pathological tau aggregates is known to improve cognitive deficits in AD animal models. The tau repeat domain (TauRD) plays a pivotal role in tau-microtubule interactions and is critically involved in the aggregation of hyperphosphorylated tau proteins. Because TauRD forms the structural core of tau aggregates, the development of immunotherapies that selectively target TauRD-induced pathological aggregates holds great promise for the modulation of tauopathies. In this study, we generated recombinant TauRD polypeptide that form neurofibrillary tangle-like structures and evaluated TauRD-specific immune responses following intranasal immunization in combination with the mucosal adjuvant FlaB. In BALB/C mice, repeated immunizations at one-week intervals induced robust TauRD-specific antibody responses in a TLR5-dependent manner. Notably, the resulting antiserum recognized only the aggregated form of TauRD, while ignoring monomeric TauRD. The antiserum effectively inhibited TauRD filament formation and promoted the phagocytic degradation of TauRD aggregate fragments by microglia. The antiserum also specifically recognized pathological tau conformers in the human AD brain. Based on these results, we engineered a built-in flagellin-adjuvanted TauRD (FlaB-TauRD) vaccine and tested its efficacy in a P301S transgenic mouse model. Mucosal immunization with FlaB-TauRD improved quality of life, as indicated by the amelioration of memory deficits, and alleviated tauopathy progression. Notably, the survival of the vaccinated mice was dramatically extended. In conclusion, we developed a mucosal vaccine that exclusively targets pathological tau conformers and prevents disease progression.
PubMed: 38879560
DOI: 10.1038/s41541-024-00904-1 -
Scientific Reports Jun 2024Apolipoprotein E (ApoE) is involved in cholesterol transport among cells and also plays an important role in amyloid formation, co-depositing with amyloid fibrils in...
Apolipoprotein E (ApoE) is involved in cholesterol transport among cells and also plays an important role in amyloid formation, co-depositing with amyloid fibrils in various types of amyloidosis. Although the in vivo amyloidogenicity of ApoE has not been previously demonstrated, this study provides evidence of ApoE amyloidogenicity in leopard geckos (Eublepharis macularius), belonging to the class Reptilia. Histologically, amyloid deposits were localized within cholesterol granulomas and exhibited positive Congo red staining, with yellow to green birefringence under polarized light. On mass spectrometry-based proteomic analysis, ApoE was detected as a dominant component of amyloid; of the full length of the 274 amino acid residues, peptides derived from Leu185-Arg230 were frequently detected with non-tryptic truncations. Immunohistochemistry with anti-leopard gecko ApoE antibody showed positive reactions of amyloid deposits. These results show that ApoE is an amyloid precursor protein within the cholesterol granulomas of leopard geckos. Although further investigations are needed, the C-terminal region of ApoE involved in amyloid formation is a lipid-binding region, and there should be a relationship between amyloidogenesis and the development of cholesterol granulomas in leopard geckos. This study provides novel insights into the pathogenesis of ApoE-related diseases.
Topics: Animals; Lizards; Cholesterol; Apolipoproteins E; Amyloid; Granuloma; Proteomics
PubMed: 38877049
DOI: 10.1038/s41598-024-64643-y