Transmembrane Tumor Necrosis Factor-alpha Research Articles

Antitumor effect of CAR-T cells targeting transmembrane tumor necrosis factor alpha combined with PD-1 mAb on breast cancers

BackgroundOur previous study showed that transmembrane tumor necrosis factor alpha (tmTNF-α) is overexpressed in primary breast cancers including triple-negative breast cancers (TNBCs). Chimeric antigen receptor engineered-T (CAR-T) cells have been...

Suppression of Transmembrane Tumor Necrosis Factor Alpha Processing by a Specific Antibody Protects Against Colitis-Associated Cancer.

Soluble tumor necrosis factor-α (sTNF-α) plays an important role in colitis-associated cancer (CAC); however, little is known about transmembrane TNF-α (tmTNF-α). Here, we observed an increase in sTNF-α mainly in colitis tissues from an azoxymethane/dextran sodium sulfate (DSS)-induced CAC mouse model whereas tmTNF-α levels were chiefly increased on epithelial cells at the tumor stage. The ratio of intracolonic tmTNF-α/sTNF-α was negatively correlated with the levels of pro-inflammatory mediators (IL-1β, IL-6, and NO) and M1 macrophages but positively correlated with the infiltration of myeloid-derived suppressor cells, regulatory T cells, and the level of the anti-inflammatory cytokine IL-10, suggesting an anti-inflammatory effect of tmTNF-α. This effect of tmTNF-α was confirmed again by the induction of resistance to LPS in colonic epithelial cell lines NCM460 and HCoEpiC through the addition of exogenous tmTNF-α or transfection of the tmTNF-α leading sequence that lacks the extracellular segment but retains the intracellular domain of tmTNF-α. A tmTNF-α antibody was used to block tmTNF-α shedding after the first or second round of inflammation induction by DSS drinking to shift the time window of tmTNF-α expression ahead to the inflammation stage. Antibody treatment significantly alleviated inflammation and suppressed subsequent adenoma formation, accompanied by increased apoptosis. An antitumor effect was also observed when the antibody was administered at the malignant phase of CAC. Our results reveal tmTNF-α as a novel molecular marker for malignant transformation in CAC and provide a new insight into blocking the pathological process by targeting tmTNF-α processing.

Forward and Reverse Signaling Mediated by Transmembrane Tumor Necrosis Factor-Alpha and TNF Receptor 2: Potential Roles in an Immunosuppressive Tumor Microenvironment.

Tumor necrosis factor-alpha (TNF-α) is a pleiotropic inflammatory cytokine produced mainly by activated macrophages, lymphocytes and other cell types. Two distinct forms of TNF-α have been identified: soluble TNF-α (sTNF-α) and transmembrane TNF-α (mTNF-α). mTNF-α, which is the precursor of sTNF-α, can be cleaved by the TNF-α converting enzyme (TACE) and is released as sTNF-α. sTNF-α binds primarily to TNF receptor 1 (TNFR1) and plays an important role in the inflammatory immune response, whereas mTNF-α interacts primarily with TNF receptor 2 (TNFR2) and mediates the promotion of cellular proliferation and survival and other biological effects. It has been reported that the interaction between mTNF-α and TNFR2 induces bi-directional (forward and reverse) signaling in both mTNF-α- and TNFR2-expressing cells. Increasing evidence shows that the forward and reverse signaling mediated by mTNF-α and TNFR2 might play a significant role in the tumor microenvironment. In this review, the role of the crosstalk between mTNF-α and TNFR2 in the tumor microenvironment will be discussed.

Transmembrane tumor necrosis factor-alpha sensitizes adipocytes to insulin

Transmembrane TNF-α (tmTNF-α) acts both as a ligand, delivering ‘forward signaling’ via TNFR, and as a receptor, transducing ‘reverse signaling’. The contradiction of available data regarding the effect of tmTNF-α on insulin resistance may be due to imbalance in both signals. Here, we demonstrated that high glucose-induced impairment of insulin-stimulated glucose uptake by 3T3-L1 adipocytes was concomitant with decreased tmTNF-α expression and increased soluble TNF-α (sTNF-α) secretion. However, when TACE was inhibited, preventing the conversion of tmTNF-α to sTNF-α, this insulin resistance was partially reversed, indicating a salutary role of tmTNF-α. Treatment of 3T3-L1 adipocytes with exogenous tmTNF-α promoted insulin-induced phosphorylation of IRS-1 and Akt, facilitated GLUT4 expression and membrane translocation, and increased glucose uptake while addition of sTNF-α resulted in the opposite effect. Furthermore, tmTNF-α downregulated the production of IL-6 and MCP-1 via NF-κB inactivation, as silencing of A20, an inhibitor for NF-κB, by siRNA, abolished this effect of tmTNF-α. However, tmTNF-α upregulated adiponectin expression through the PPAR-γ pathway, as inhibition of PPAR-γ by GW9662 abrogated both tmTNF-α-induced adiponectin transcription and glucose uptake. Our data suggest that tmTNF-α functions as an insulin sensitizer via forward signaling.

Segmental vitiligo after infliximab use for rheumatoid arthritis - A case report

The tumor necrosis factor alpha is a cytokine related to immune and inflammatory processes by acting on different parts of the body. It is secreted by several cell types including macrophages, lymphocytes, monocytes, neutrophils, dendritic cells, among others. Infliximab is a chimeric monoclonal antibody that specifically binds to soluble and transmembrane tumor necrosis factor alpha form blocking its action. In rheumatoid arthritis it is used because the cytokines that cause inflammation in this disease are regulated by tumor necrosis factor alpha and IL-1. We report the case of a 46-year-old patient with rheumatoid arthritis who developed segmental vitiligo after two months using infliximab. The event aims to alert to the existence of this adverse effect that can be induced with the use of this medication.

Translational Research Efforts in Biomarkers and Biology of Early Transplant-Related Complications

In the time since the first allogeneic hematopoietic stem cell transplantation (HSCT) was performed over 40 years ago, this life-saving procedure has been used increasingly for patients with hematologic, metabolic, and malignant diseases. Despite major advances in our understanding of the immunologic processes (both beneficial and injurious) that are associated with HSCT and improvements in supportive and critical care medicine, successful outcomes are still limited by several serious complications. As such, the establishment of effective therapeutic strategies for these complications will be crucial as increasing numbers of high-risk transplants are performed each year. The development of such approaches is fundamentally dependent upon a basic understanding of pathophysiologic mechanisms of disease and also on our ability to successfully translate these insights back to the bedside. This brief review will highlight breakthroughs in translational research endeavors that have paved the way for the development of novel strategies intended to change the standard of care and optimize outcomes for patients in whom allogeneic HSCT offers the only hope for a cure.

Interleukin-15 and Its Soluble Receptor Mediate the Response to Infliximab in Patients With Crohn's Disease

Infliximab is a monoclonal antibody against tumor necrosis factor that is used to treat patients with inflammatory bowel disease. We investigated serum levels and cellular expression of interleukin (IL)-15 and its receptor (sIL-15Ralpha) in patients with Crohn's disease (CD) treated with infliximab; and the effect on sIL-15Ralpha secretion by epithelial cells. CD patients were given infliximab (n = 40; 3 infusions); 37 healthy controls were studied. Serum levels of IL-15, sIL-15Ralpha, and complex were determined by radioimmunoassay and cytokine levels by enzyme-linked immunosorbent assay. IL-15Ralpha and A Desintegrin and Metalloproteinase 17 levels were assessed by immunohistochemistry. Epithelial cell lines (HT-29 and Caco-2) were cultured with infliximab, adalimumab, or etanercept. Patients were classified as responders and nonresponders according to their Crohn's Disease Activity Index and clinical observations. Before infliximab, IL-15 was higher in responders than in controls and nonresponders. After infliximab, IL-15 decreased in responders while remaining stable in nonresponders. sIL-15Ralpha and IL-15/sIL-15Ralpha complex levels were higher in CD than in controls and increased only in responders after infliximab. IL-15Ralpha and A Desintegrin and Metalloproteinase 17 colocalized in epithelial cells and were higher in CD patients. In vitro, infliximab but not adalimumab and etanercept induced sIL-15Ralpha secretion by epithelial cells. Serum level of sIL-15Ralpha and the IL-15/sIL-15Ralpha complex increased in responder patients and the response was associated with a decrease of IL-15. Infliximab induced the release of the IL-15 receptor alpha, suggesting a specific modulation of IL-15 and its soluble receptor by reverse signaling through transmembrane tumor necrosis factor alpha.

Transmembrane Tumor Necrosis Factor Alpha Is Required for Enteropathy and Is Sufficient To Promote Parasite Expulsion in Gastrointestinal Helminth Infection

To study the specific role of transmembrane tumor necrosis factor (tmTNF) in protective and pathological responses against the gastrointestinal helminth Trichinella spiralis, we compared the immune responses of TNF-alpha/lymphotoxin alpha (LTalpha)(-/-) mice expressing noncleavable transgenic tmTNF to those of TNF-alpha/LTalpha(-/-) and wild-type mice. The susceptibility of TNF-alpha/LTalpha(-/-) mice to T. spiralis infection was associated with impaired induction of a protective Th2 response and the lack of mucosal mastocytosis. Although tmTNF-expressing transgenic (tmTNF-tg) mice also had a reduced Th2 response, the mast cell response was greater than that observed in TNF-alpha/LTalpha(-/-) mice and was sufficient to induce the expulsion of the parasite. T. spiralis infection of tmTNF-tg mice resulted in significant intestinal pathology characterized by villus atrophy and crypt hyperplasia comparable to that induced following the infection of wild-type mice, while pathology in TNF-alpha/LTalpha(-/-) mice was significantly reduced. Our data thus indicate a role for tmTNF in host defense against gastrointestinal helminths and in the accompanying enteropathy. Furthermore, they also demonstrate that TNF-alpha is required for the induction of Th2 immune responses related to infection with gastrointestinal helminth parasites.

Distribution and tumor necrosis factor-alpha isoform binding specificity of locally administered etanercept into injured and uninjured rat sciatic nerve

Tumor necrosis factor-alpha (TNF) is a pro-inflammatory cytokine that is implicated in the initiation of neuropathic pain. Locally administered TNF antagonist etanercept offers a promising new treatment approach to target neuropathic pain. Here we evaluate the distribution and binding specificity for TNF isoforms of locally administered etanercept into injured and uninjured rat sciatic nerve. Distribution and co-localization of etanercept and TNF in the injured and uninjured nerve was evaluated at 1, 24, 48 and 96 h after etanercept local application using immunohistochemistry. In addition, binding specificity of etanercept for TNF isoforms was analyzed using immunoblot assay system in nerve lysates. A new observation was that locally administered etanercept reached the endoneurium of the injured but not the uninjured nerve 1 h after its application and mainly co-localized with TNF-positive structures, morphologically similar to Schwann cells and macrophages. We further noticed that immunoblot analyses for etanercept demonstrated its preferential binding to transmembrane and trimer TNF isoforms. Finally, locally administered etanercept inhibited pain-related behaviors in a rat sciatic nerve crush model. We conclude that locally administered etanercept reaches the endoneurial space in the injured nerve and preferentially binds to transmembrane and bioactive trimer TNF isoforms to modulate neuropathic pain. Locally administered etanercept has potential as a targeted immunomodulating agent to treat local pathogenesis in neuropathic pain after peripheral nerve injury.

Lipid rafts uncouple surface expression of transmembrane TNF-α from its cytotoxicity associated with ICAM-1 clustering in Raji cells

Since transmembrane tumor necrosis factor-alpha (tmTNF-α) has been reported to have a palmitoylated site at Cys−47, and therefore its functions may be linked to lipid raft membrane microdomains. The present study tested a hypothesis that lipid rafts may serve as a signaling platform to mediate the bioactivity of tmTNF-α. We found that destruction of lipid rafts with methyl-beta-cyclodextrin (MCD) in Raji cells almost completely blocked the cytotoxicity of tmTNF-α, as did an anti-TNF-α antibody. Although a proportion of tmTNF-α was colocated with lipid rafts, either the replacement of Cys at −47 by Ala, destructing its possible lipid rafts-attaching site or the displacement of its cytoplasmic domain by the C-terminal sequence (131–157) of caveolin-1, making all tmTNF-α target to lipid rafts, had no effect on tmTNF-α cytotoxicity. The data suggest that the cytotoxicity of tmTNF-α is not associated with its lipid rafts location. Unparallel to decreased cytotoxicity, moreover, MCD significantly increased tmTNF-α expression on the cell surface, and these increased tmTNF-α molecules were capable of binding to sTNFR1. To further explore the mechanism of lipid rafts-mediated cytotoxicity of tmTNF-α, we demonstrated that MCD led to a marked decrease in adhesion of Raji cells to T24 cells, which was due to dissociation of adhesion molecule ICAM-1 from lipid rafts. These results indicate that lipid rafts importantly participate in the cytotoxicity of tmTNF-α through ICAM-1 clustering and consequent enhancement of the cell–cell contact. The data suggest that lipid rafts are essential for the killing of tmTNF-α through the cell–cell contact mediated by ICAM-1. However, lipid rafts may limit exposure of tmTNF-α to the cell surface.

291. Comparison of Anti-Tumor Effects between Transmembrane and Secretory Tumor Necrosis Factor-alpha In Vitro and In Vivo

Tumor necrosis factor-alpha (TNF-a) exists naturally in two forms, transmembrane and secretory form. In the present study, three recombinant retroviral vectors containing human wild type TNF-a (Wt-TNF), secretory TNF-a (S-TNF, a mutant replaced its signal peptide by that of IL-2), and transmembrane TNF-a (TM-TNF, a mutant deleted a site for cleavage of TNF into the secretory form) were constructed respectively and transfected stably into murine hepatic carcinoma cell line (H22). TNF-a either secreted in supernatants by S-TNF and Wt-TNF producing tumor cells or expressed on cell surface of TM-TNF and Wt-TNF synthesizing tumor cells was demonstrated to be cytotoxic against TNF sensitive L929 cells. Also, the H22 cells transfected with three types of TNF-a can kill parental H22 in effect/target (E/T) dependent manner in vitro and their maximal killing rates were about 38|[sim]|43% at E/T ratio of 5:1. Injection of total 2.5|[prime]|105 cells mixed with transfected and parental H22 tumor cells at different ratios into syngeneic mice resulted in the inhibition of tumor growth and their maximal inhibition rates were about 57|[sim]|72% at E/T 5:1. A transient weight loss was found in mice bearing S-TNF producing tumors, whereas no obvious side effects were seen in mice bearing TM-TNF or Wt-TNF expressing tumors. It has been shown that S-TNF secreting tumor promoted significantly lymphocytes infiltration and attracted more CD4+ T cells than CD8+ T cells to the tumor site, while TM-TNF expressing tumor stimulated Fas expression and inhibited a tumor metastasis associated molecule CD44v3 expression on tumor cells. These results suggest that S-TNF and TM-TNF kill cancer cells in vivo through different mechanisms and that transmembrane form of TNF-a might be a safer candidate for tumor gene therapy due to its less side effects and retainable antitumor activity.

Mutational analysis of region-cytotoxicity relationship in human transmembrane tumor necrosis factor-alpha

Objective To determine the region of human transmembrane tumor necrosis factor-alpha (TM-TNFα), essential for cytotoxic activity against human breast cancer cell line MCF-7.