InVivoMAb polyclonal mouse IgG

• Cancer Research
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Small Extracellular Vesicle-Derived vWF Induces a Positive Feedback Loop between Tumor and Endothelial Cells to Promote Angiogenesis and Metastasis in Hepatocellular Carcinoma.

In Advanced Science (Weinheim, Baden-Wurttemberg, Germany) on 1 September 2023 by Wong, S. W. K., Tey, S. K., et al.

PubMed

Hepatocellular carcinoma (HCC) is a hypervascular malignancy by which its growth and dissemination are largely driven by the modulation of tumor-derived small extracellular vesicles (sEVs). Proteomic profiling of circulating sEVs of control individuals and HCC patients identifies von Willibrand factor (vWF) to be upregulated progressively along HCC stages. Elevated sEV-vWF levels are found in a larger cohort of HCC-sEV samples and metastatic HCC cell lines compared to their respective normal counterparts. Circulating sEVs of late-stage HCC patients markedly augment angiogenesis, tumor-endothelial adhesion, pulmonary vascular leakiness, and metastasis, which are significantly compromised by anti-vWF antibody. The role of vWF is further corroborated by the enhanced promoting effect of sEVs collected from vWF-overexpressing cells. sEV-vWF modulates endothelial cells through an elevated level of vascular endothelial growth factor A (VEGF-A) and fibroblast growth factor 2 (FGF2). Mechanistically, secreted FGF2 elicits a positive feedback response in HCC via the FGFR4/ERK1 signaling pathway. The co-administration of anti-vWF antibody or FGFR inhibitor significantly improves the treatment outcome of sorafenib in a patient-derived xenograft mouse model. This study reveals mutual stimulation between HCC and endothelial cells by tumor-derived sEVs and endothelial angiogenic factors, facilitating angiogenesis and metastasis. It also provides insights into a new therapeutic strategy involving blocking tumor-endothelial intercellular communication. © 2023 The Authors. Advanced Science published by Wiley-VCH GmbH.

Blockade of OX40/OX40L signaling using anti-OX40L delays disease progression in murine lupus

Preprint on Research Square on 11 July 2023 by Zhao, J., Li, L., et al.

PubMed

Objectives: OX40 ligand (OX40L) locus genetic variants have relationships with the risk for systemic lupus erythematosus (SLE), OX40L blockade has been shown to ameliorate renal damage and suppress autoantibody production in NZB/W F1 mice. However, it is unclear how OX40L blockade delays lupus phenotype. Methods In present study, we examined the impact of blocking OX40L using anti-OX40L in the MRL/lpr murine model of lupus. Mice were sorted into 3 groups with 9 ~ 11 mice per group as follows: IgG treatment, Cyclophosphamide (CTX) treatment, and anti-OX40L treatment. Treated mice were harvested, and samples of serum, kidney, and spleen were collected for outcome evaluation. Next, we investigated the impact of anti-OX40L on immunosuppression in KLH-immunized C57BL/6J mice aged 8 weeks through the detection of serum immunoglobulins (Igs) and splenocyte flow cytometry. In vitro treatment of anti-OX40L in CD4 + T and CD19 + B cells were used for exploring the roles of OX40L in SLE pathogenesis. Results Anti-OX40L delayed disease progression in MRL/lpr mice, accompanied by decreased production of anti-dsDNA, proteinuria, and Ig deposition in kidney, as well as lower frequencies of Th1 and Tfh cells in the spleen. Compared to the IgG group, anti-OX40L was found to up-regulate polyclonal CD4 + T cell differentiation into Tregs in vitro. In KLH-immunized mice, decreased levels of Igs, and plasmablast cells were observed in anti-OX40L group. Blocking OX40/OX40L signaling also inhibited TLR7-mediated differentiation of antibody secreting cells (ASCs) and production of antibody through the up-regulation of SPI-B, IRF8, and PAX5, and down-regulation of Xbp-1 in B cells in vitro . Conclusion Together, these results propose OX40L as a promising therapeutic target for SLE.

• Immunology and Microbiology

Rapid, site-specific labeling of "off-the-shelf" and native serum autoantibodies with T cell-redirecting domains.

In Science Advances on 6 May 2022 by Zappala, F., Higbee-Dempsey, E., et al.

PubMed

Extensive antibody engineering and cloning is typically required to generate new bispecific antibodies. Made-to-order genes, advanced expression systems, and high-efficiency cloning can simplify and accelerate this process, but it still can take months before a functional product is realized. We developed a simple method to site-specifically and covalently attach a T cell-redirecting domain to any off-the-shelf, human immunoglobulin G (IgG) or native IgG isolated from serum. No antibody engineering, cloning, or knowledge of the antibody sequence is required. Bispecific antibodies are generated in just hours. By labeling antibodies isolated from tumor-bearing mice, including two syngeneic models, we generated T cell-redirecting autoantibodies (TRAAbs) that act as an effective therapeutic. TRAAbs preferentially bind tumor tissue over healthy tissue, indicating a previously unexplored therapeutic window. The use of autoantibodies to direct the tumor targeting of bispecific antibodies represents a new paradigm in personalized medicine that eliminates the need to identify tumor biomarkers.

• Immunology and Microbiology

VISTA Blockade Aggravates Bone Loss in Experimental Murine Apical Periodontitis.

In Frontiers in Immunology on 26 October 2021 by Yang, F., Zhang, Y., et al.

PubMed

V-domain Ig suppressor of T cell activation (VISTA) is a novel coinhibitory immune checkpoint molecule that maintains immune homeostasis. The present study explored the role of VISTA in human and murine inflammatory tissues of apical periodontitis (AP). VISTA was upregulated in inflammatory tissues of human AP. In mice, the expression of VISTA gradually increased with the development of mouse experimental apical periodontitis (MAP), the CD3+ T cells, CD11b+ myeloid cells, and FOXP3+ regulatory T cells also gradually accumulated. Moreover, a blockade of VISTA using a mouse in vivo anti-VISTA antibody aggravated periapical bone loss and enhanced the infiltration of immune cells in an experimental mouse periapical periodontitis model. The collective results suggest that VISTA serves as a negative regulator of the development and bone loss of apical periodontitis. Copyright © 2021 Yang, Zhang, Chen and Zhang.

• Cancer Research

Identification ACTA2 and KDR as key proteins for prognosis of PD-1/PD-L1 blockade therapy in melanoma.

In Animal Models and Experimental Medicine on 1 June 2021 by Wang, Y., Li, Z., et al.

PubMed

Programmed cell death protein 1 (PD-1) /programmed cell death ligand 1 (PD-L1) blockade is an important therapeutic strategy for melanoma, despite its low clinical response. It is important to identify genes and pathways that may reflect the clinical outcomes of this therapy in patients. We analyzed clinical dataset GSE96619, which contains clinical information from five melanoma patients before and after anti-PD-1 therapy (five pairs of data). We identified 704 DEGs using these five pairs of data, and then the number of DEGs was narrowed down to 286 in patients who responded to treatment. Next, we performed KEGG pathway enrichment and constructed a DEG-associated protein-protein interaction network. Smooth muscle actin 2 (ACTA2) and tyrosine kinase growth factor receptor (KDR) were identified as the hub genes, which were significantly downregulated in the tumor tissue of the two patients who responded to treatment. To confirm our analysis, we demonstrated similar expression tendency to the clinical data for the two hub genes in a B16F10 subcutaneous xenograft model. This study demonstrates that ACTA2 and KDR are valuable responsive markers for PD-1/PD-L1 blockade therapy. © 2021 The Authors. Animal Models and Experimental Medicine published by John Wiley Sons Australia, Ltd on behalf of The Chinese Association for Laboratory Animal Sciences.

• Mus musculus (House mouse)
,
• Immunology and Microbiology

Tissue-Resident Type 2 Innate Lymphoid Cells Arrest Alveolarization in Bronchopulmonary Dysplasia.

In Journal of Immunology Research on 13 November 2020 by Mi, L., Zhu, S., et al.

PubMed

Bronchopulmonary dysplasia (BPD) is a severe complication of the respiratory system associated with preterm birth. Type 2 innate lymphoid cells (ILC2s) play a major role in tissue homeostasis, inflammation, and wound healing. However, the role in BPD remains unclear. The present study showed that ILC2s, interleukin-4 (IL-4), IL-13, and anti-inflammatory (M2) macrophages increased significantly in BPD mice as compared to the control mice. Administration with recombinant mouse IL-33 amplified the above phenomena and aggravated the alveolar structural disorder and functional injury in mice subjected to BPD, and the opposite was true with anti-ST2 antibody. In addition, the depletion of ILC2s in BPD mice with anti-CD90.2 antibody substantially abolished the destructive effect on BPD. In the treatment of BPD with dexamethasone, the number of ILC2s and M2 macrophages and levels of IL-4 and IL-13 decreased with remission as compared to the control group. This study identified a major destructive role of the ILC2s in BPD that could be attenuated as a therapeutic strategy. Copyright © 2020 Lanlan Mi et al.

• Cancer Research

Identification ACTA2 and KDR as Key Proteins for Prognosis of PD-1/PD-L1 Blockade Therapy in Melanoma

Preprint on Research Square on 2 July 2020 by Wang, Y., Li, Z., et al.

PubMed

h4>Background: /h4> Programmed cell death protein 1 (PD-1) /programmed cell death ligand 1 (PD-L1) blockade is an important therapeutic strategy for melanoma, despite its low clinical response. It is important to identify genes and pathways that may reflect the clinical outcomes of this therapy in patients. h4>Methods: /h4> In this study, we analyzed clinical dataset GSE96619, which contains clinical information from five melanoma patients before and after anti-PD-1 therapy (five pairs of data). Two of the five patients responded to the anti-PD-1 treatment, whereas the other three patients did not respond to the treatment. We used MetaboAnalyst to identify differentially expressed genes (DEGs). The significant GO terms and KEGG pathway enrichment analysis of the identified DEGs were performed by using DAVID. The STRING v10 online tool was used to construct and visualize the PPI network. Validation the expression of hub genes in the B16F10 subcutaneous xenograft model h4>Results: /h4> We identified 704 DEGs using these five pairs of data, and then the number of DEGs was narrowed down to 286 in patients who responded to treatment. Next, we performed KEGG pathway enrichment and constructed a DEG-associated protein-protein interaction network. Smooth muscle actin 2 (ACTA2) and tyrosine kinase growth factor receptor (KDR) were identified as the hub genes, which were significantly downregulated in the tumor tissue of the two patients who responded to treatment. To confirm our analysis, we demonstrated similar expression tendency to the clinical data for the two hub genes in a B16F10 subcutaneous xenograft model. h4>Conclusions: /h4> This study demonstrates that ACTA2 and KDR are valuable responsive markers for PD-1/PD-L1 blockade therapy.

• In Vivo
,
• Control
,
• Mus musculus (House mouse)
,
• Biochemistry and Molecular biology
,
• Cell Biology
,
• Immunology and Microbiology

Inflammation mobilizes copper metabolism to promote colon tumorigenesis via an IL-17-STEAP4-XIAP axis.

In Nature Communications on 14 February 2020 by Liao, Y., Zhao, J., et al.

PubMed

Copper levels are known to be elevated in inflamed and malignant tissues. But the mechanism underlying this selective enrichment has been elusive. In this study, we report a axis by which inflammatory cytokines, such as IL-17, drive cellular copper uptake via the induction of a metalloreductase, STEAP4. IL-17-induced elevated intracellular copper level leads to the activation of an E3-ligase, XIAP, which potentiates IL-17-induced NFκB activation and suppresses the caspase 3 activity. Importantly, this IL-17-induced STEAP4-dependent cellular copper uptake is critical for colon tumor formation in a murine model of colitis-associated tumorigenesis and STEAP4 expression correlates with IL-17 level and XIAP activation in human colon cancer. In summary, this study reveals a IL-17-STEAP4-XIAP axis through which the inflammatory response induces copper uptake, promoting colon tumorigenesis.

• Cancer Research
,
• Immunology and Microbiology

DDR1 promotes breast tumor growth by suppressing antitumor immunity.

In Oncology Reports on 1 December 2019 by Zhong, X., Zhang, W., et al.

PubMed

Breast cancer is the second leading cause of cancer‑associated mortality among women worldwide. Triple‑negative breast cancer (TNBC) accounts for 15‑20% of all breast cancers and is defined by its aggressive nature and limited treatment options. Therefore, there is an urgent need to develop effective therapies for TNBC in order to improve breast cancer outcomes, as targeted therapies have done in other subtypes of breast cancer. Discoidin domain receptor tyrosine kinase 1 (DDR1) is activated by collagens, which are important components of the tumor stroma; therefore, DDR1 may serve a critical role in the communication between tumor cells and the tumor microenvironment. The aim of the present study was to determine how tumor DDR1 regulated tumor growth by affecting tumor infiltrated T cells. First, the DDR1 expression levels from a cohort of patients with breast cancer were analyzed. The results revealed that there were higher levels of DDR1 expression in tumor tissues compared with adjacent normal tissues. Overexpression of DDR1 in 4T1 cells promoted tumor growth in vivo, while knockout of DDR1 in EMT6 cells decreased tumor growth in vivo. In addition, it was revealed that DDR1 regulated tumor growth by modulating tumor infiltrating T cells, CD4+ and CD8+. Furthermore, inhibition of DDR1 by neutralizing antibodies decreased breast cancer growth in vivo. To the best of our knowledge, the results of the present study demonstrated for the first time that DDR1 expressed on the tumor cells promoted breast tumor growth by suppressing antitumor immunity. The present findings indicated that DDR1 may not only have a critical role in the progression of breast cancer, but may also serve as a potential therapeutic target for breast cancer, particularly TNBC.

• Immunology and Microbiology

Non-invasive Imaging of Sendai Virus Infection in Pharmacologically Immunocompromised Mice: NK and T Cells, but not Neutrophils, Promote Viral Clearance after Therapy with Cyclophosphamide and Dexamethasone.

In PLoS Pathogens on 1 September 2016 by Mostafa, H. H., Vogel, P., et al.

PubMed

In immunocompromised patients, parainfluenza virus (PIV) infections have an increased potential to spread to the lower respiratory tract (LRT), resulting in increased morbidity and mortality. Understanding the immunologic defects that facilitate viral spread to the LRT will help in developing better management protocols. In this study, we immunosuppressed mice with dexamethasone and/or cyclophosphamide then monitored the spread of viral infection into the LRT by using a noninvasive bioluminescence imaging system and a reporter Sendai virus (murine PIV type 1). Our results show that immunosuppression led to delayed viral clearance and increased viral loads in the lungs. After cessation of cyclophosphamide treatment, viral clearance occurred before the generation of Sendai-specific antibody responses and coincided with rebounds in neutrophils, T lymphocytes, and natural killer (NK) cells. Neutrophil suppression using anti-Ly6G antibody had no effect on infection clearance, NK-cell suppression using anti-NK antibody delayed clearance, and T-cell suppression using anti-CD3 antibody resulted in no clearance (chronic infection). Therapeutic use of hematopoietic growth factors G-CSF and GM-CSF had no effect on clearance of infection. In contrast, treatment with Sendai virus-specific polysera or a monoclonal antibody limited viral spread into the lungs and accelerated clearance. Overall, noninvasive bioluminescence was shown to be a useful tool to study respiratory viral progression, revealing roles for NK and T cells, but not neutrophils, in Sendai virus clearance after treatment with dexamethasone and cyclophosphamide. Virus-specific antibodies appear to have therapeutic potential.