scholarly journals Multifaceted glycoadjuvant@AuNPs inhibits tumor metastasis through promoting T cell activation and remodeling tumor microenvironment

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Xiaojing Xu ◽  
Minfeng Gan ◽  
Youzhen Ge ◽  
Cheng Yi ◽  
Tianyun Feng ◽  
...  

Abstarct Background Cytosine-phosphate-guanine (CpG) dinucleotides has been used as adjuvants for cancer immunotherapy. However, unmodified CpG are not very efficient in clinical trials. Glucose, ligand of C-type lectin receptors (CLRs), can promote DC maturation and antigen presentation, which is the first step of induction of adaptive immune responses. Therefore, conjugation of type B CpG DNA to glucose-containing glycopolymers may enhance the therapeutic effects against tumor by CpG-based vaccine. Methods gCpG was developed by chemical conjugation of type B CpG DNA to glucose-containing glycopolymers. The therapeutic effects of gCpG-based vaccine were tested in both murine primary melanoma model and its metastasis model. Results gCpG based tumor vaccine inhibited both primary and metastasis of melanoma in mice which was dependent on CD8 + T cells and IFNγ. In tumor microenvironment, gCpG treatment increased Th1 and CTL infiltration, increased M1 macrophages, decreased Tregs and MDSCs populations, and promoted inflammatory milieu with enhanced secretion of IFNγ and TNFα. The anti-tumor efficacy of gCpG was dramatically enhanced when combined with anti-PD1 immunotherapy. Conclusions We confirmed that gCpG was a promising adjuvant for vaccine formulation by activating both tumor-specific Th1 and Tc1 responses, and regulating tumor microenvironments. Graphical Abstract

2021 ◽  
Vol 39 (15_suppl) ◽  
pp. e14565-e14565
Author(s):  
Amit Adhikari ◽  
Juliete Macauley ◽  
Yoshimi Johnson ◽  
Mike Connolly ◽  
Tim Coleman ◽  
...  

e14565 Background: Glioblastoma (GBM) is an aggressive form of brain cancer with a median survival of 15 months which has remained unchanged despite technological advances in the standard of care. GBM cells specifically express human cytomegalovirus (HCMV) proteins providing a unique opportunity for targeted therapy. Methods: We utilized our UNITE (UNiversal Intracellular Targeted Expression) platform to develop a multi-antigen DNA vaccine (ITI-1001) that codes for the HCMV proteins- pp65, gB and IE-1. The UNITE platform involves lysosomal targeting technology, fusing lysosome-associated protein 1 (LAMP1) with target antigens resulting in increased antigen presentation by MHC-I and II. ELISpot, flow cytometry and ELISA techniques were used to evaluate the vaccine immunogenicity and a syngeneic, orthotopic GBM mouse model that expresses HCMV proteins was used for efficacy studies. The tumor microenvironment studies were done using flow cytometry and MSD assay. Results: ITI-1001 vaccination showed a robust antigen-specific CD4 and CD8 T cell response in addition to a strong humoral response. Using GBM mouse model, therapeutic treatment of ITI-1001 vaccine resulted in ̃56% survival with subsequent long-term immunity. Investigating the tumor microenvironment showed significant CD4 T cell infiltration as well as enhanced Th1 and CD8 T cell activation. Regulatory T cells were also upregulated upon ITI-1001 vaccination and would be an attractive target to further improve this therapy. In addition, tumor burden negatively correlated with number of activated CD4 T cells (CD4 IFNγ+) reiterating the importance of CD4 activation in ITI-1001 efficacy and potentially identifying treatment responders and non-responders. Further characterization of these two groups showed high infiltration of CD3+, CD4+ and CD8+ T cells in responders compared with non- responders along with higher CD8 T cell activation. Conclusions: Thus, we show that vaccination with HCMV antigens using the ITI-1001-UNITE platform generates strong cellular and humoral immune responses, triggering significant anti-tumor activity that leads to enhanced survival in mice with GBM.


1998 ◽  
Vol 188 (12) ◽  
pp. 2335-2342 ◽  
Author(s):  
Siquan Sun ◽  
Xiaohong Zhang ◽  
David F. Tough ◽  
Jonathan Sprent

Immunostimulatory DNA and oligodeoxynucleotides containing unmethylated CpG motifs (CpG DNA) are strongly stimulatory for B cells and antigen-presenting cells (APCs). We report here that, as manifested by CD69 and B7-2 upregulation, CpG DNA also induces partial activation of T cells, including naive-phenotype T cells, both in vivo and in vitro. Under in vitro conditions, CpG DNA caused activation of T cells in spleen cell suspensions but failed to stimulate highly purified T cells unless these cells were supplemented with APCs. Three lines of evidence suggested that APC-dependent stimulation of T cells by CpG DNA was mediated by type I interferons (IFN-I). First, T cell activation by CpG DNA was undetectable in IFN-IR−/− mice. Second, in contrast to normal T cells, the failure of purified IFN-IR−/− T cells to respond to CpG DNA could not be overcome by adding normal IFN-IR+ APCs. Third, IFN-I (but not IFN-γ) caused the same pattern of partial T cell activation as CpG DNA. Significantly, T cell activation by IFN-I was APC independent. Thus, CpG DNA appeared to stimulate T cells by inducing APCs to synthesize IFN-I, which then acted directly on T cells via IFN-IR. Functional studies suggested that activation of T cells by IFN-I was inhibitory. Thus, exposing normal (but not IFN-IR−/−) T cells to CpG DNA in vivo led to reduced T proliferative responses after TCR ligation in vitro.


Author(s):  
Fuwen Yao ◽  
Yongqiang Zhan ◽  
Zuhui Pu ◽  
Ying Lu ◽  
Jiao Chen ◽  
...  

Gastric cancer (GC) is a malignant disease of the digestive tract and a life-threatening disease worldwide. Ferroptosis, an iron-dependent cell death caused by lipid peroxidation, is reported to be highly correlated with gastric tumorigenesis and immune cell activity. However, the underlying relationship between ferroptosis and the tumor microenvironment in GC and potential intervention strategies have not been unveiled. In this study, we profiled the transcriptome and prognosis data of ferroptosis-related genes (FRGs) in GC samples of the TCGA-STAD dataset. The infiltrating immune cells in GC were estimated using the CIBERSORT and XCELL algorithms. We found that the high expression of the hub FRGs (MYB, PSAT1, TP53, and LONP1) was positively correlated with poor overall survival in GC patients. The results were validated in an external GC cohort (GSE62254). Further immune cell infiltration analysis revealed that CD4+ T cells were the major infiltrated cells in the tumor microenvironment of GC. Moreover, the hub FRGs were significantly positively correlated with activated CD4+ T cell infiltration, especially Th cells. The gene features in the high-FRG score group were enriched in cell division, DNA repair, protein folding, T cell receptor, Wnt and NIK/NF-kappaB signaling pathways, indicating that the hub FRGs may mediate CD4+ T cell activation by these pathways. In addition, an upstream transcriptional regulation network of the hub FRGs by lncRNAs was also developed. Three lncRNAs (A2M-AS1, C2orf27A, and ZNF667-AS1) were identified to be related to the expression of the hub FRGs. Collectively, these results showed that lncRNA A2M-AS1, C2orf27A, and ZNF667-AS1 may target the hub FRGs and impair CD4+ T cell activation, which finally leads to poor prognosis of GC. Effective interventions for the above lncRNAs and the hub FRGs can help promote CD4+ T cell activation in GC patients and improve the efficacy of immunotherapy. These findings provide a novel idea of GC immunotherapy and hold promise for future clinical application.


Author(s):  
Nádia Ghinelli Amôr ◽  
Paulo Sérgio da Silva Santos ◽  
Ana Paula Campanelli

Squamous cell carcinoma (SCC) is the second most common skin cancer worldwide and, despite the relatively easy visualization of the tumor in the clinic, a sizeable number of SCC patients are diagnosed at advanced stages with local invasion and distant metastatic lesions. In the last decade, immunotherapy has emerged as the fourth pillar in cancer therapy via the targeting of immune checkpoint molecules such as programmed cell-death protein-1 (PD-1), programmed cell death ligand-1 (PD-L1), and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4). FDA-approved monoclonal antibodies directed against these immune targets have provide survival benefit in a growing list of cancer types. Currently, there are two immunotherapy drugs available for cutaneous SCC: cemiplimab and pembrolizumab; both monoclonal antibodies (mAb) that block PD-1 thereby promoting T-cell activation and/or function. However, the success rate of these checkpoint inhibitors currently remains around 50%, which means that half of the patients with advanced SCC experience no benefit from this treatment. This review will highlight the mechanisms by which the immune checkpoint molecules regulate the tumor microenvironment (TME), as well as the ongoing clinical trials that are employing single or combinatory therapeutic approaches for SCC immunotherapy. We also discuss the regulation of additional pathways that might promote superior therapeutic efficacy, and consequently provide increased survival for those patients that do not benefit from the current checkpoint inhibitor therapies.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. SCI-46-SCI-46
Author(s):  
Melody A. Swartz

Tumor engagement or activation of surrounding lymphatic vessels is well-known to correlate with tumor progression and metastasis in melanoma and many other cancers. We and others have identified several mechanisms by which the lymphatic growth factor VEGF-C and lymphangiogenesis can promote metastasis, including (i) increasing immune suppressive cell types and factors in the tumor microenvironment both directly and indirectly, (ii) inhibiting maturation of antigen-presenting cells and T cell activation, and (iii) driving changes in the stromal microenvironment that promote both cancer invasion and immune suppression. However, lymphatic activation also enhances communication with cells in the draining lymph node by antigen and cell transport, which may trigger the initiation of adaptive immune responses against the tumor. Under normal conditions, the potential anti-tumor effects are rendered 'dormant' by the pro-tumor immune suppression, and the tumor progresses. However, we are now observing that lymphangiogenic tumors are exceptionally responsive to immunotherapy, implying that the anti-tumor aspects can be unleashed when the overall balance of pro- and anti-tumor immune aspects is tipped enough towards the latter (e.g., upon tumor cell killing). On the mechanistic side, we are finding that 'lymphangiogenic potentiation' depends on tumor cell infiltration of both CD103+ dendritic cells and naïve T cells, driving local T cell education post-immunotherapy and antigen spreading. On the translational side, we are developing novel strategies to exploit lymphangiogenesis for cancer immunotherapy. Understanding the yin and yang of lymphatic activation in the tumor microenvironment and how it affects immunity may lead to exciting new translational strategies for cancer immunotherapy. Disclosures No relevant conflicts of interest to declare.


2020 ◽  
Vol 52 (12) ◽  
pp. 1926-1935
Author(s):  
Gun-Young Jang ◽  
Ji won Lee ◽  
Young Seob Kim ◽  
Sung Eun Lee ◽  
Hee Dong Han ◽  
...  

AbstractDamage-associated molecular patterns (DAMPs) are danger signals (or alarmins) alerting immune cells through pattern recognition receptors (PRRs) to begin defense activity. Moreover, DAMPs are host biomolecules that can initiate a noninflammatory response to infection, and pathogen-associated molecular pattern (PAMPs) perpetuate the inflammatory response to infection. Many DAMPs are proteins that have defined intracellular functions and are released from dying cells after tissue injury or chemo-/radiotherapy. In the tumor microenvironment, DAMPs can be ligands for Toll-like receptors (TLRs) expressed on immune cells and induce cytokine production and T-cell activation. Moreover, DAMPs released from tumor cells can directly activate tumor-expressed TLRs that induce chemoresistance, migration, invasion, and metastasis. Furthermore, DAMP-induced chronic inflammation in the tumor microenvironment causes an increase in immunosuppressive populations, such as M2 macrophages, myeloid-derived suppressor cells (MDSCs), and regulatory T cells (Tregs). Therefore, regulation of DAMP proteins can reduce excessive inflammation to create an immunogenic tumor microenvironment. Here, we review tumor-derived DAMP proteins as ligands of TLRs and discuss their association with immune cells, tumors, and the composition of the tumor microenvironment.


2019 ◽  
Vol 8 (11) ◽  
pp. 1989 ◽  
Author(s):  
Tom J. Harryvan ◽  
Els M. E. Verdegaal ◽  
James C. H. Hardwick ◽  
Lukas J. A. C. Hawinkels ◽  
Sjoerd H. van der Burg

The introduction of a wide range of immunotherapies in clinical practice has revolutionized the treatment of cancer in the last decade. The majority of these therapeutic modalities are centered on reinvigorating a tumor-reactive cytotoxic T-cell response. While impressive clinical successes are obtained, the majority of cancer patients still fail to show a clinical response, despite the fact that their tumors express antigens that can be recognized by the immune system. This is due to a series of other cellular actors, present in or attracted towards the tumor microenvironment, including regulatory T-cells, myeloid-derived suppressor cells and cancer-associated fibroblasts (CAFs). As the main cellular constituent of the tumor-associated stroma, CAFs form a heterogeneous group of cells which can drive cancer cell invasion but can also impair the migration and activation of T-cells through direct and indirect mechanisms. This singles CAFs out as an important next target for further optimization of T-cell based immunotherapies. Here, we review the recent literature on the role of CAFs in orchestrating T-cell activation and migration within the tumor microenvironment and discuss potential avenues for targeting the interactions between fibroblasts and T-cells.


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