Fas Receptor Research Articles

Abstract LB065: Tumor-infiltrating lymphocytes (TIL) engineered with regulatable membrane-bound IL15 (mbIL15) and LIGHT (TNFSF14) show enhanced efficacy in fibroblast-containing cold tumors

Abstract Introduction: Adoptive cellular therapies (ACT) have encountered challenges in solid tumors due in part to the immunosuppressive tumor microenvironment (TME). We have developed OBX-115, TIL engineered to express mbIL15 regulatable using the cytoDRiVE® platform, which allows for TIL expansion, persistence, and anti-tumor efficacy under control of the FDA-approved small-molecule ligand, acetazolamide (ACZ), eliminating the need for co-administration of IL2 (NCT05470283). LIGHT, a tumor necrosis factor family member, interacts with lymphotoxin beta receptor (LTbR) and herpes virus entry mediator (HVEM) found on various TME cell types, including stromal cells such as cancer associated fibroblasts (CAF). In preclinical studies, LIGHT expression within a tumor has been linked to the formation of tertiary lymphoid structures and vascular normalization (Ramachandran Cancer Cell 2023), both associated with better clinical outcomes (Sautès-Fridman Nat Rev Cancer 2019). We hypothesized that engineering TIL with regulatable mbIL15 and LIGHT expression could enhance their efficacy by modifying the TME. Methods: TIL from colorectal (CRC) and head and neck squamous cell carcinoma (HNSCC) were transduced with retroviral vectors to express regulatable mbIL15 and LIGHT. ACZ-induced surface expression of mbIL15 and LIGHT in expanded TIL was examined using flow cytometry. Functional signaling of LIGHT was assessed through co-culture with Jurkat-HVEM-NF-kappaB reporter cells and LTbR+ HUVEC cells. In vitro, engineered TIL were tested in stromal-rich tumor models (CRC and HNSCC) by co-culturing with autologous patient-derived tumor/CAF hybrid spheroids. In vivo, antigen-independent TIL persistence was assessed in NSG mice without exogenous IL2. Syngeneic studies were performed to assess the efficacy of adoptively transferred mbIL15 and LIGHT-engineered Pmel cells (CD8+ T cells transgenic for a gp100-specific T cell receptor) in a subcutaneous cold tumor model (B16-F10). Results: Engineered TIL were successfully expanded without exogenous IL2. ACZ-dependent mbIL15 and LIGHT expression were confirmed, validating co-regulation and functionality in vitro. TIL engineered with mbIL15 and LIGHT displayed significantly increased cytotoxicity against autologous tumor/CAF spheroids compared with TIL expressing mbIL15 alone (p<0.005) in CRC and HNSCC tumor/CAF hybrid models. TIL with mbIL15 and LIGHT expanded in vivo and persisted for ≥42 days without exogenous IL2 support. Moreover, Pmel cells engineered with mbIL15 and LIGHT demonstrated durable anti-tumor efficacy in B16-F10 tumor-bearing mice, which was greater than Pmel cells engineered with mbIL15 alone (p<0.01). Conclusions: These preclinical results suggest that TIL engineered with regulatable mbIL15 and LIGHT using the cytoDRiVE platform have the potential to address the high unmet clinical need in cold tumors with suppressive TME, which are currently not amenable to ACT. Citation Format: Balazs Koscso, Zheng Ao, Carmela Passaro, Nirzari Shah, Ngoc Ly, Patricia Timpug, Bulent A. Aksoy, Dexue Sun, Dan Jun Li, Kerri-Lynn Sheahan, Violet Young, Theresa Ross, Benjamin Primack, Meghan Langley, Jeremy Tchaicha, Dhruv K. Sethi, Jan ter Meulen, Michelle Ols. Tumor-infiltrating lymphocytes (TIL) engineered with regulatable membrane-bound IL15 (mbIL15) and LIGHT (TNFSF14) show enhanced efficacy in fibroblast-containing cold tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB065.

Abstract 120: A closer Look at colorectal cancer risk: Insights from the complex relationship of HIV, helminths, and immune responses

Abstract The advent of antiretroviral therapy has markedly increased the survival rates of individuals with human immunodeficiency virus (HIV). However, this demographic, particularly in low-middle-income countries (LMICs) where HIV-helminth co-infections are prevalent, remains susceptible to infections. The intricate interplay between helminth infections and HIV susceptibility, often inducing immunological phenotypes that heighten vulnerability, remains poorly understood. Studies have shown the association between HIV-helminth co-infections and elevated susceptibility to colorectal cancer (CRC), introducing an additional layer of health concerns for this already vulnerable population. This retrospective observational study delves into the profound effects of HIV-helminth co-infections on immune responses, with a specific focus on type 2 T helper (Th2) cell immunomodulation and susceptibility to CRC. Utilizing samples from a master project (n=414), 80 systematically randomized individuals were categorized into uninfected control, HIV-infected only, helminth-infected only, and HIV-helminth co-infected groups. Parasite detection employed the Kato-Katz technique, and serum testing was conducted for helminth-specific antibodies. Serological HIV testing, viral load categorization, white blood cell counts, and differential analyses were performed. Human ProcartaPlex Panel 1 was used for cytokine profiling of immune stimulatory and inhibitory soluble proteins. A significant reduction in B and T lymphocyte attenuator (BTLA) (p=0.049) in helminth infections compared to the control. The association of BTLA with its ligand, herpesvirus entry mediator (HVEM), establishes a direct link between the CD28 and tumor necrosis factor receptor (TNFR) families, triggering wide-ranging and robust immune responses. Subsequently, a notable reduction in CD28 was observed in HIV-infected subjects (p=0.003), followed by helminth-infected and HIV-helminth co-infected individuals (p=0.03) compared to the control. Furthermore, programmed death ligand-2 (PD-L2) expression, a major contributor to alternatively activated macrophage polarization during helminth infections, was significantly increased in the HIV-helminth co-infected group (p = 0.05), favoring a shift towards Th2 immune responses. These observed alterations underscore the complexity of the immunological interplay in co-infected individuals, emphasizing an additional risk factor for colorectal cancer development. This necessitates a comprehensive understanding, providing valuable insights for the development of therapeutic strategies in LMICs and similar settings, addressing the heightened risk of CRC within this population. Citation Format: Botle P. Damane, Thanyani V. Mulaudzi, Sayed S. Kader, Ropo E. Ogunsakin, Pragalathan Naidoo, Zodwa Dlamini, Zilungile L. Mkhize-Kwitshana. A closer Look at colorectal cancer risk: Insights from the complex relationship of HIV, helminths, and immune responses [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 120.

Abstract 3995: A novel chimeric Fas signal redirect receptor enhances the durability of anti-tumor activity and serial killing potential of CAR T cells

Abstract Chimeric antigen receptor (CAR) T-cell therapies have demonstrated remarkable success in hematological malignancies but only modest efficacy in solid tumors. Apoptosis induced by Fas receptor signaling can be a substantial barrier to CAR T-cell antitumor activity, as many solid tumors express high levels of Fas ligand (FasL). Here we describe a novel synthetic construct where the ectodomain of Fas receptor is fused to the signaling endodomain of a stimulatory receptor, creating a Fas signal redirect receptor (Fas-SRR). This unique design not only prevents Fas-dependent cell death, but also augments the long-term killing potential of induced pluripotent stem cell (iPSC)-derived CAR-T (CAR-iT) cells. Fas-SRR constructs with unique T-cell activation signaling endodomains were designed and compared to two control arms: a dominant negative receptor (Fas-DNR), which blocks Fas signal but does not promote activation; and a Fas-41BB fusion receptor, where the 41BB endodomain is fused to FasR ectodomain to direct activation upon FasL:Fas engagement. Fas-SRR designs were validated in Jurkat reporter cells treated with Fas agonist to measure signal redirection via Fas-SRR. To conduct a head-to-head comparison, CAR-iT cells were engineered to express a CAR under the regulation of the TRAC locus and to express either a Fas-DNR, a Fas-41BB, or FAS-SRR constructs at high purity (>90% transgene expression). No major differences were seen in maturation phenotype (>95% TRAC-CAR expression) of these cells, indicating compatibility of the FAS-SRR constructs with CAR-iT cell generation. Functional testing of the Fas-SRR+ CAR-iT cells was performed in a long-term restimulation assay where effector cells were repeatedly exposed to target cells over multiple rounds of co-culture. Complete loss of target cell lysis was observed by round six in the co-cultures with FAS-DNR cells, where loss of CAR-iT cell persistence led to accumulation of target cells. After eight rounds of co-culture, the Fas-41BB cells and the majority of Fas-SSR cell constructs also began to exhibit minimal activity toward target cells. However, the top Fas-SRR cell constructs continued to show durable antitumor activity (>97% cytolysis) through the end of the 9-round rechallenge assay. Of note, GSEA analysis identified significant upregulation of NFkB and RELA target genes in cells having the top FAS-SRR construct versus the less durable designs. These results reinforce the advantage of attenuating Fas-FasL interactions to prevent apoptosis and, more importantly, demonstrate the unique therapeutic value in redirecting Fas signaling to improve T-cell potency over an extended duration. Additional studies are underway to further investigate the implications of Fas signal redirection in CAR T and CAR-iT cells and to further understand the module of genes involved in supporting serial stimulation performance. Citation Format: Christopher Ecker, Eigen Peralta, Hui-Yi Chu, Lorraine Loter, Masanao Tsuda, Earl Avramis, Matthew Denholtz, Alec Witty, Tom Lee, Bahram Valamehr. A novel chimeric Fas signal redirect receptor enhances the durability of anti-tumor activity and serial killing potential of CAR T cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3995.

Growth performance, hematological profile, and related genes expression in goldfish (Carassius auratus) fed on rosmarinic acid-enriched diets and subjected to ambient ammonia

Recently, supplementing fish diets with polyphenols has attracted more attention because of their great nutritional role. The unionized ammonia is one of the critical water parameters that adversely affects the fish performance and welfare status. Hence, the present perspective outlines the potential value of dietary rosmarinic acid (RA) in boosting growth, hematological, and immune biomarkers, besides related-genes expressions post-exposure of goldfish (Carassius auratus) to ambient ammonia. Fish (n = 240) were separated into four groups; RA0 (the control), RA400, RA600, and RA800 received 0, 400, 600, and 800 mg RA/kg feed, respectively. After 56 days, counts of white and red blood cells and growth indices (weight gain, specific growth rate, feed intake, and feed conversion ratio) were evaluated. After that, the fish per each treatment were exposed to 0.5 mg/L of unionized ammonia for three hours. After the challenging time, many biomarkers were measured including immune response (ACH50, total immunoglobulin, and lysozymes activity), digestion (proteases activity), and genes expression involving MUC, HSP27, HSP30, HSP47, TNFa, Lp1, and Fas genes plus the anti-inflammatory cytokines (IL6, IL8, and IL10). The findings of the current research revealed that dietary RA intervention fostered growth performance, improved blood picture (p < 0.05), and enhanced (p < 0.05) the expression of genes, which are responsible for modulating immunity and anti-inflammatory status in a dose-dependent manner. The present study concluded that dietary RA is a successful natural feed supplement for goldfish with an optimal level of 600 mg RA/kg feed. However, it verifies antitoxic and anti-inflammatory properties against ambient ammonia toxicity. It also has a promising influence on the growth, hematological, and immunity and anti-inflammatory related genes expression of goldfish, C. auratus.

The role of the BTLA-HVEM complex in the pathogenesis of breast cancer.

Breast cancer (BC) is widely recognized as a prevalent contributor to cancer mortality and ranks as the second most prevalent form of cancer among women across the globe. Hence, the development of innovative therapeutic strategies is imperative to effectively manage BC. The B- and T-lymphocyte attenuator (BTLA)-Herpesvirus entry mediator (HVEM) complex has garnered significant scientific interest as a crucial regulator in various immune contexts. The interaction between BTLA-HVEM ligand on the surface of T cells results in reduced cellular activation, cytokine synthesis, and proliferation. The BTLA-HVEM complex has been investigated in various cancers, yet its specific mechanisms in BC remain indeterminate. In this study, we aim to examine the function of BTLA-HVEM and provide a comprehensive overview of the existing evidence in relation to BC. The obstruction or augmentation of these pathways may potentially enhance the efficacy of BC treatment.

Synthesis of N-Glycosylated Soluble Fas Ligand.

Controlled cell death is essential for the regulation of the immune system and plays a role in pathogen defense. It is often altered in pathogenic conditions such as cancer, viral infections and autoimmune diseases. The Fas receptor and its corresponding membrane-bound ligand (FasL) are part of the extrinsic apoptosis pathway activated in these cases. A soluble form of FasL (sFasL), produced by ectodomain shedding, displays a diverse but still elusive set of non-apoptotic functions and sometimes even serves as a pro-survival factor. To gather more knowledge about the characteristics of this protein and the impact N-glycosylations may have, access to homogeneous posttranslationally modified variants of sFasL is needed. Therefore, we developed a flexible strategy to obtain such homogeneously N-glycosylated variants of sFasL by applying chemical protein synthesis. This strategy can be flexibly combined with enzymatic methods to introduce more complex, site selective glycosylations.

Rotator Cuff Tendinopathy: Pathways of Apoptosis.

Rotator cuff repair is usually successful, but retear is not uncommon. It has been previously identified that there is a higher incidence of apoptosis in the edges of the torn supraspinatus tendon. A prospective cohort study was conducted with 28 patients-14 rotator cuff tear patients, 5 instability patients, and 9 Anterior cruciate ligament reconstruction patients to determine whether there was any increase in several genes implicated in apoptosis, including Fas receptor (FasR), Fas ligand, Aifm-1, Bcl-2, Fadd, Bax, and caspase-3. There was a significant expression of Bax (P=0.2) and FasR (P=0.005) in the edges of torn supraspinatus tendons, and in intact subscapularis tendons, there was a significant expression of caspase-3 (P=0.02) compared with samples from the torn supraspinatus tendon (P=0.04). The cytochrome c pathway, with its subsequent activation of caspase-3, as well as the TRAIL-receptor signaling pathway involving FasR have both been implicated. The elevated expression of Bax supported the model that the Bax to Bcl-2 expression ratio represents a cell death switch. The elevated expression of Bax in the intact subscapularis tissue from rotator cuff tear patients also may confirm that tendinopathy is an ongoing molecular process.

Evaluation of carcass traits, meat quality and the expression of lipid metabolism-related genes in different slaughter ages and muscles of Taihang black goats.

This study was conducted to investigate the effect of slaughter age on carcass traits, meat quality, and the relative mRNA levels of lipid metabolism-related genes in different muscles of Taihang black goats. In this study, the triceps brachii (TB), longissimus dorsi (LD) and gluteus (GL) muscles of 15 grazing Taihang black goats slaughtered at the age of 2, 3, and 4 (designated as 2-year-old, 3-year-old, and 4-year-old, respectively) were collected. The differences in carcass shape, meat quality, amino acid composition and lipid metabolism gene expression among Taihang black goats of different ages and from different plant parts were compared. Compared with goats at other ages, goats slaughtered at the age of 4 had greater live and carcass weights, meat weights, bone weights and skin areas (p<0.05). LD in the 4-years-old had the lowest cooking loss and moisture content. The crude protein content in the LD of 2-year-old was significantly greater than that in the other age group, and at the age of 2, the LD had the highest crude protein content than TB and GL. The highest fat content was in LD, followed by TB, for goats slaughtered at the age of 4. Eight out of 9 essential amino acids had higher content in the TB compared with other muscles, regardless of age. The total essential amino acid content was highest in the 4-year-old and lowest in the GL muscle at the age of 3. The sterol regulatory element-binding protein-1c (SREBP-1c) and adipose triglyceride lipase (ATGL) genes were significantly more abundant in the TB muscle than in the other muscles for goats slaughtered at the age of 2. At the age of 4, the ATGL and peroxisome proliferator-activated receptor γ (PPARγ) genes were significantly more abundant in the GL than in the LD, while the fatty acid synthase (FAS) genes were significantly less abundant in the GL than in the other muscles. Similarly, compared with those in goats of other ages, the relative mRNA expression levels of the FAS and heart-type fatty acid binding protein (H-FABP) genes in goats slaughtered at the age of 4 were the highest, and the relative mRNA expression of the PPARγ gene was the lowest (p<0.05). The relative mRNA expression of the H-FABP and FAS genes was positively correlated with the intramuscular fat (IMF) content, while the relative mRNA expression levels of the PPARγ and ATGL genes was negatively correlated with the IMF content. Overall, a better nutritional value was obtained for TB from 4-year-old goats, in which the total essential amino acid and fat contents were greater than those of other muscles. The comprehensive action of lipid metabolism genes was consistent with that of the IMF content, among which the FAS, H-FABP, PPARγ, and ATGL genes had positive and negative effects on the process of IMF deposition in Taihang black goats.

Cortisol as a cerebral cortex neurons apoptosis regulator in acute phase of ischemic stroke (clinical and pathological study)

In response to ischemic stroke (IS) a natural activation of the stress-realizing system occurs. The features of this activation influence the outcome of the acute period and the prognosis of recovery and can be adjusted. At the same time, the role of the stress-realizing system in the pathogenesis of IS is still unexplored.Objective: to investigate the effect of peripheral blood cortisol concentration on the regulation of apoptosis of neurons of the cerebral cortex in the acute phase of IS.Material and methods. A prospective clinical and pathological study was performed. It included 9 patients with IS in the left middle cerebral artery territory who were admitted to hospital and died in the hyperacute phase of IS and had no infectious complications, allergic reactions or oncological diseases and who did not undergo thrombolysis. The cerebral cortex was examined. Neuron-specific enolase (NSE), protein 53 (p53), caspase 3, caspase 8, Fas receptor (CD95), and Fas apoptotic inhibitory molecule 2 (FAIM2) were determined on the slices using an indirect immunoperoxidase immunohistochemical staining method. A total of 567 microscopic fields were analysed for the group of patients with IS and 63 fields for the control group (three people). Before death, the blood concentrations of sFas, sFasL, cortisol, adrenocorticotropic hormone, adrenaline and norepinephrine were determined by enzyme immunoassay (the control group consisted of 28 people).Results. Significant correlation was found between the proportion of casp3-positive neurons and the concentration of cortisol in peripheral blood in zones 2 (r=0.263; p&lt;0.01) and 3 (r=0.383; p&lt;0.01). In the 2nd zone, significant negative correlation was found with the concentrations of sFas (r=-0.177; p&lt;0.05) and sFasL (r=-0.164; p&lt;0.05); in the 3rd zone, significant positive correlation was found with the ratio of the concentrations of sFasL and sFas (r=0.240; p&lt;0.01). The proportion of Fas-positive neurons in the cerebral cortex correlated significantly with the concentration of the soluble form of this molecule (for the 1st zone – r=0.222, for the 2nd zone – r=0.438, for the 3rd zone – r=0.289; p&lt;0.01) and the ratio of the concentrations of sFasL and sFas (respectively: r=0.231, r=0.266 and r=0.281; p&lt;0.01) in the peripheral blood.Conclusion. Peripheral blood cortisol concentration is a factor that determines the regulation of apoptosis of neurons in the cerebral cortex in the acute phase of IS.

Intranasal Delivery of Anti-Apoptotic siRNA Complexed with Fas-Signaling Blocking Peptides Attenuates Cellular Apoptosis in Brain Ischemia.

Ischemic stroke-induced neuronal cell death leads to the permanent impairment of brain function. The Fas-mediating extrinsic apoptosis pathway and the cytochrome c-mediating intrinsic apoptosis pathway are two major molecular mechanisms contributing to neuronal injury in ischemic stroke. In this study, we employed a Fas-blocking peptide (FBP) coupled with a positively charged nona-arginine peptide (9R) to form a complex with negatively charged siRNA targeting Bax (FBP9R/siBax). This complex is specifically designed to deliver siRNA to Fas-expressing ischemic brain cells. This complex enables the targeted inhibition of Fas-mediating extrinsic apoptosis pathways and cytochrome c-mediating intrinsic apoptosis pathways. Specifically, the FBP targets the Fas/Fas ligand signaling, while siBax targets Bax involved in mitochondria disruption in the intrinsic pathway. The FBP9R carrier system enables the delivery of functional siRNA to hypoxic cells expressing the Fas receptor on their surface-a finding validated through qPCR and confocal microscopy analyses. Through intranasal (IN) administration of FBP9R/siCy5 to middle cerebral artery occlusion (MCAO) ischemic rat models, brain imaging revealed the complex specifically localized to the Fas-expressing infarcted region but did not localize in the non-infarcted region of the brain. A single IN administration of FBP9R/siBax demonstrated a significant reduction in neuronal cell death by effectively inhibiting Fas signaling and preventing the release of cytochrome c. The targeted delivery of FBP9R/siBax represents a promising alternative strategy for the treatment of brain ischemia.

Potential of Melittin to induce apoptosis and overcome multidrug resistance in human colon cancer cell line

In this study, the anticancer effect of Melittin was demonstrated through its antiproliferative and proapoptotic effects on HT-29 cells, as well as its ability to reverse multidrug resistance. Melittin directly affects the death receptor-dependent apoptotic pathway via increase of the Fas receptor protein expression, Caspase 8 gene expression and activity of Caspase 8. Results of decreased Caspase 9 gene and protein expression, and multi-fold increased expression of Bcl-2 gene suggest that mitochondria and the inner apoptotic pathway are not involved in the execution of Melittin induced apoptosis, as well as redox regulation of apoptosis based on decreased concentration of superoxide anion radicals and no effect glutathione levels. Specially significance of this work are results on ability of Melittin to modulate the metabolism and export system in cancer cells. Based on the increased expression of all the investigated genes related to the biotransformation process, it can be assumed that CYP1A1, CYP1B1, GSTP1 and MRP2 are involved in metabolism of Melittin in HT-29 cells. P-glycoprotein is associated with the occurrence of resistance in anticancer therapy, so its reduced gene and protein expression by Melittin represents significant result in terms of possible therapeutic application and examination.

Cyclizine induces cytotoxicity and apoptosis in macrophages through the extrinsic and intrinsic apoptotic pathways.

Cyclizine, an over-the-counter and prescription antihistamine, finds widespread application in the prevention and treatment of motion sickness, encompassing symptoms such as nausea, vomiting, dizziness, along with its effectiveness in managing vertigo. However, the overuse or misuse of cyclizine may lead to hallucinations, confusion, tachycardia, and hypertension. The molecular mechanisms underlying cyclizine-induced cytotoxicity and apoptosis remain unclear. During the 24 h incubation duration, RAW264.7 macrophages were exposed to different concentrations of cyclizine. Cytotoxicity was assessed through the lactate dehydrogenase assay. Flow cytometry employing annexin V-fluorescein isothiocyanate and propidium iodide was utilized to evaluate apoptosis and necrosis. Caspase activity and mitochondrial dysfunction were evaluated through a fluorogenic substrate assay and JC-1 dye, respectively. Flow cytometry employing fluorogenic antibodies was utilized to evaluate the release of cytochrome c and expression of death receptor, including tumor necrosis factor-α receptor and Fas receptor. Western blotting was utilized to evaluate the expression of the Bcl2 and Bad apoptotic regulatory proteins. The findings unveiled from the present study demonstrated that cyclizine exerted a concentration-dependent effect on RAW264.7 macrophages, leading to the induction of cytotoxicity, apoptosis, and necrosis. This compound further activated the intrinsic apoptotic pathway by inducing mitochondrial dysfunction, Bcl2/Bad exchange expression, cytochrome c liberation, and activation of caspases contained caspase 3, 8, and 9. Moreover, the activation of the extrinsic apoptotic pathway was observed as cyclizine induced the upregulation of death receptors and increased caspase activities. Based on our investigations, it can be inferred that cyclizine prompts cytotoxicity and apoptosis in RAW264.7 macrophages in a concentration-dependent manner by triggering both the intrinsic and extrinsic apoptotic pathways.

Microarray data analysis of antileukemic action of Cinnamoylated benzaldehyde LQB-461 in Jurkat cell line.

Leukemias stand out for being the main type of childhood cancer in the world. Current treatments have strong side effects for patients, and there is still a high rate of development of resistance to multidrug therapy. Previously, our research group developed a structure-activity study with novel synthetic molecules analogous to LQB-278, described as an essential molecule with in vitro antileukemic action. Among these analogs, LQB-461 stood out, presenting more significant antileukemic action compared to its derivative LQB-278, with cytostatic and cytotoxicity effect by apoptosis, inducing caspase-3, and increased sub-G1 phase on cell cycle analysis. Deepening the study of the mechanism of action of LQB-461 in Jurkat cells in vitro, a microarray assay was carried out, which confirmed the importance of the apoptosis pathway in the LQB-461 activity. Through real-time PCR, we validated an increased expression of CDKN1A and BAX genes, essential mediators of the apoptosis intrinsic pathway. Through the extrinsic apoptosis pathway, we found an increased expression of the Fas receptor by flow cytometry, showing the presence of a more sensitive population and another more resistant to death. Considering the importance of autophagy in cellular resistance, it was demonstrated by western blotting that LQB-461 decreased LC-3 protein expression, an autophagic marker. These results suggest that this synthetic molecule LQB-461 induces cell death by apoptosis in Jurkat cells through intrinsic and extrinsic pathways and inhibits autophagy, overcoming some mechanisms of cell resistance related to this process, which differentiates LQB-461 of other drugs used for the leukemia treatment.

CD4+ T cell-derived IFN-γ and LIGHT synergistically upregulate chemokine production from airway smooth muscle cells.

Airway smooth muscle (ASM) remodeling in asthmatic airways may contribute to persistent airflow limitation and airway hyperresponsiveness. CD4+ T cells infiltrate the ASM layer where they may induce a proliferative and secretory ASM cell phenotype. We studied the interaction between activated CD4+ T cells and ASM cells in co-culture invitro and investigated the effects of CD4+ T cells on chemokine production by ASM cells. CD4+ T cells induced marked upregulation of C-X-C motif chemokine ligands (CXCL) 9, 10, and 11 in ASM cells. Blockade of the IFN-γ receptor on ASM cells prevented this upregulation. Furthermore, T cell-derived IFN-γ and LIGHT (lymphotoxin, exhibits inducible expression and competes with HSV glycoprotein D for binding to herpesvirus entry mediator, a receptor expressed on T lymphocytes) synergize in a dose-dependent manner to coordinately enhance CXCL9, 10, and 11 expression. The synergistic property of LIGHT was mediated exclusively through the lymphotoxin-β receptor (LTBR), but not herpes virus entry mediator (HVEM). Disruption of LTBR signaling in ASM cells reduced CXCL9, 10, and 11 production and ASM cell-mediated CD4+ T cell chemotaxis. We conclude that the LIGHT-LTBR signaling axis acts together with IFN-γ to regulate chemokines that mediate lymphocyte infiltration in asthmatics.

Sunitinib malate induces cell death in adult human cardiac progenitor cells

Sunitinib malate is known to cause cardiotoxicity in a sub-population of patients, with heart failure seen in more severe cases. Cardiac progenitor cells (CPCs) have been identified in adult human myocardium and contribute to overall tissue maintenance, with previous work identifying negative impacts of sunitinib on these cells. This study aimed to characterise the toxic effects of sunitinib in human CPCs, applying sunitinib concentrations equivalent to clinical plasma levels to these cells in vitro. Cell viability was reduced by 26.5 ± 6.6 % by 2 μM sunitinib for 24 h (p < 0.01); this concentration also induced fold-change increases in gene expression of: calpain (3.1 ± 0.73, p < 0.05), FAS (2.3 ± 0.8, p < 0.05) and BAX (1.9 ± 0.2, p < 0.05), and a decrease in BCL-2 (3.5 ± 0.0, p < 0.001), vs. control (1.0 ± 0.0). This was affirmed by sunitinib inducing fold changes in protein expression of: calpain-1 (2.5 ± 0.5, p < 0.05); FAS receptor (2.1 ± 0.2, p < 0.05) and BAX (2.1 ± 0.2, p < 0.05) vs. control (1.0 ± 0.0). These results indicated that sunitinib induced apoptosis in CPCs, but negative annexin V staining and lack of protection by caspase inhibitors indicated this was not the cell death pathway activated. Further investigation found sunitinib was concentrated in the lysosomes and autophagosomes within CPCs, but did not induce accumulation of acidic organelles. In conclusion, these data confirm that cell death is caused by sunitinib in CPCs at concentrations equivalent to clinical plasma levels, inducing cell death pathway signals that lead to non-apoptotic cell death.

Pneumonia in the first week after polytrauma is associated with reduced blood levels of soluble herpes virus entry mediator.

Pneumonia develops frequently after major surgery and polytrauma and thus in the presence of systemic inflammatory response syndrome (SIRS) and organ dysfunction. Immune checkpoints balance self-tolerance and immune activation. Altered checkpoint blood levels were reported for sepsis. We analyzed associations of pneumonia incidence in the presence of SIRS during the first week of critical illness and trends in checkpoint blood levels. Patients were studied from day two to six after admission to a surgical intensive care unit (ICU). Blood was sampled and physician experts retrospectively adjudicated upon the presence of SIRS and Sepsis-1/2 every eight hours. We measured the daily levels of immune checkpoints and inflammatory markers by bead arrays for polytrauma patients developing pneumonia. Immune checkpoint time series were additionally determined for clinically highly similar polytrauma controls remaining infection-free during follow-up. We performed cluster analyses. Immune checkpoint time trends in cases and controls were compared with hierarchical linear models. For patients with surgical trauma and with and without sepsis, selected immune checkpoints were determined in study baseline samples. In polytrauma patients with post-injury pneumonia, eleven immune checkpoints dominated subcluster 3 that separated subclusters 1 and 2 of myeloid markers from subcluster 4 of endothelial activation, tissue inflammation, and adaptive immunity markers. Immune checkpoint blood levels were more stable in polytrauma cases than controls, where they trended towards an increase in subcluster A and a decrease in subcluster B. Herpes virus entry mediator (HVEM) levels (subcluster A) were lower in cases throughout. In unselected surgical patients, sepsis was not associated with altered HVEM levels at the study baseline. Pneumonia development after polytrauma until ICU-day six was associated with decreased blood levels of HVEM. HVEM signaling may reduce pneumonia risk by strengthening myeloid antimicrobial defense and dampening lymphoid-mediated tissue damage. Future investigations into the role of HVEM in pneumonia and sepsis development and as a predictive biomarker should consider the etiology of critical illness and the site of infection.

Discriminating Between Apoptosis, Necrosis, Necroptosis, and Ferroptosis by Microscopy and Flow Cytometry.

Apoptosis is a mode of programmed cell death that plays important roles in tissue sculpting during development, in the maintenance of tissue homeostasis in the adult, and in the eradication of injured or infected cells during pathological processes. Numerous physiological as well as pathological stimuli trigger apoptosis, such as engagement of plasma-membrane-associated Fas, TRAIL, or TNF receptors, growth factor deprivation, hypoxia, radiation, and exposure to diverse cytotoxic drugs. Apoptosis is coordinated by members of the caspase family of cysteine proteases, which, upon activation, trigger a series of dramatic morphological and biochemical changes including retraction from the substratum, cell shrinkage, extensive and protracted plasma membrane blebbing, chromatin condensation, DNA hydrolysis, nuclear fragmentation, and proteolytic cleavage of numerous caspase substrates. These dramatic structural and biochemical alterations result not only in the controlled dismantling of the cell, but also in the rapid recognition and removal of apoptotic cells by phagocytes through the cell surface display of phagocytotic triggers such as phosphatidylserine. Necrosis, which is typically nonprogrammed or imposed upon the cell by overwhelming membrane or organelle damage, is characterized by high-amplitude cell swelling, followed by rapid plasma membrane rupture and release of cellular contents into the extracellular space. Necrosis is often provoked by infectious agents or severe departure from physiological conditions due to toxins, temperature extremes, or physical injury. However, forms of programmed necrosis (necroptosis, pyroptosis, ferroptosis) can also occur in specific circumstances. Nonprogrammed and programmed necrosis can be distinguished from apoptosis by morphological features, based on the rapid uptake of vital dyes, and through the application of specific inhibitors of key molecules associated with the latter modes of cell death. This unit describes protocols for the measurement of apoptosis and necrosis and for distinguishing apoptosis from programmed as well as conventional necrosis. © 2023 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Analysis of cell morphology by phase-contrast microscopy Alternative Protocol 1: Assessment of morphological changes using eosin-methylene blue staining Alternative Protocol 2: Analysis of nuclear morphology by fluorescence microscopy Support Protocol: Preparation of cytospins Basic Protocol 2: Measurement of plasma membrane composition with annexin V and propidium iodide Basic Protocol 3: Measurement of DNA fragmentation by flow cytometry Alternative Protocol 3: Analysis of DNA fragmentation by the TUNEL assay Basic Protocol 4: Measurement of caspase activation by flow cytometry Basic Protocol 5: Discriminating between apoptosis, necrosis, necroptosis, and ferroptosis.

A t(14;18) Negative Nodal Diffuse Follicular Lymphoma with 1p36/TNFRSF14 LOH Detected by Cytogenomic Microarray Analysis

Abstract Introduction/Objective Among the already described variants of nodal follicular lymphoma (FL), there is a variant with diffuse growth pattern with a predilection to involve the inguinal lymph nodes and peculiar immunohistochemical and molecular characteristics. The diffuse growth pattern is manifested by the complete absence of follicles without a follicular/dendritic meshwork (negative CD21 and CD23). This variant was first described by Katzenberger in 2009. It is distinguished from other variants by CD23 expression, lack of t(14;18)/ IGH::BCL2 rearrangement, and chromosome segment 1p36 deletion or TNFRSF14 mutations. Methods/Case Report A 43-year-old Caucasian male presented with a lump in his left groin, noted by him after exercising and sought surgical opinion to rule out inguinal hernia. CT- scan of abdomen and pelvis showed a well circumscribed 4.3 cm lymph node in the left groin region. Histological analysis of the lesion depicted a lymph node with a predominantly diffuse and focally vaguely nodular proliferation effacing the architecture. Numerous centrocytes admixed with occasional centroblasts averaging &amp;lt;15/HPF. The neoplastic cells are positive for CD20, PAX5, CD10, BCL6, CD23 and BCL2, and are negative for CD5 and cyclin D1. The CD21 highlights few residual germinal centers at the periphery of the lymph node. The proliferative (Ki67+) index is approximately 30-40%. Flow cytometry demonstrates CD10 positive, kappa monoclonal B cell population (20% of total). FISH analysis was negative for both IgH/BCL2 t(14;18) rearrangement and TNFRSF14 (1p36) Deletion. However, cytogenomic microarray analysis (CMA) revealed genomic imbalances and copy neutral Loss of Heterozygosity over 1p36 in a mosaic state representing about 40% of the cells, which notably encompasses PRKC2, SKI, TNFRSF14, PRDM16, TP73 and PRL22 genes. The findings are consistent with a final diagnosis of diffuse follicular lymphoma variant, WHO grade 1-2 of 3. Results (if a Case Study enter NA) N/A Conclusion The copy neutral Loss of Heterozygosity of 1p36 region which contains TNFRSF14 gene was detected by CMA only. Undoubtedly, CMA results can play a pivotal role in identifying copy neutral Loss of Heterozygosity or small regions deletions or gains that can be missed by conventional cytogenetics and FISH studies and subsequently establishing diagnosis and prognostic stratification of hematologic neoplasms.

Herpesvirus Entry Mediator As a Novel Therapeutic Target in Multiple Myeloma

The use of immune checkpoint inhibitors has markedly improved the survival outcomes of many patients with solid tumors. However, in multiple myeloma (MM), the use of such inhibitors has failed to achieve survival benefit. We previously showed that oncolytic herpes simplex virus 1 (oHSV-1) can effectively infect MM cells and induce apoptosis through the receptors for oHSV-1, NECTIN-1 and HVEM (herpes virus entry mediator). HVEM, a member of the TNF receptor superfamily (TNFRSF14), is an immune checkpoint present on T cells, B cells, NK cells and macrophages. Depending on HVEM's interaction with its major inhibitory ligand, B- and T-lymphocyte attenuator (BTLA) or its major activating ligand, tumor necrosis factor superfamily member 14 (TNFSF14, LIGHT), it is pivotal in downmodulating or stimulating the immune cells. Accordingly, targeting HVEM to block its interaction with BTLA is an area of therapeutic interest. Flow cytometry analysis showed that HVEM was consistently expressed on the surface of all tested MM cell lines (n=9). Mass cytometry analysis of bone marrow (BM) from multi-relapsing MM patients revealed that HVEM was also expressed in different immune populations and that its expression was increased in T lymphocytes upon relapse from the anti-CD38 antibody daratumumab. Loss of function experiments by silencing RNA (siRNA) showed that, after 48hrs, HVEM knockdown significantly reduced the proliferation of the MM cell lines MM.1S (48% decrease vs control si-RNA; P˂0.0001) and H929 (35% decrease vs control si-RNA; P˂0.0001), as indicated by the MTS assay. To this end, we developed several anti-HVEM monoclonal antibodies directed against the extracellular domain of human HVEM and used surface plasmon resonance experiments and CyTOF to validate their binding. Among all antibodies tested, HVEM5 had one of the highest binding affinities, with minimal cross-reactivity with other non-cancer tissues as assessed on tissue array by imaging mass cytometry. An ELISA-based BTLA:HVEM inhibitor screening assay showed that HVEM5, but not a non-binding control (HVEM4), resulted in a 100% blockade of the interaction of HVEM with recombinant BTLA protein. Moreover, HVEM5 elicited potent antibody-dependent cellular cytotoxicity by primary NK cells against MM cell lines (MM.1S and H929), in contrast to a control human IgG (p=0.0022 and 0.0061, respectively), and was comparable to that of daratumumab (Fig.1A). Flow cytometry data showed that ex vivo HVEM5 treatment of tumor-associated macrophages (TAMs) polarized them from a M2/repair-type to a M1/kill-type, as indicated by their decreased CD163 (69% increase vs. control IgG; P=0.0011; n=4) and increased CD80 (30% increase vs control IgG; P=0.0436; n=4) expression. Furthermore, HVEM5 (10 µg/mL) treatment of peripheral blood mononuclear cells almost doubled CD8+ T lymphocytes proliferation ex vivo. To assess whether HVEM5 exerts an agonistic effect and activates HVEM-NF-κB downstream activation signaling, we used a luciferase reporter assay in a Jurkat cell line overexpressing HVEM. HVEM5 binding induced a 1.5-fold increase in NF-κB promoter activity (1.50±0.07) compared to a control human IgG (1.02±0.02) or the non-binding antibody HVEM4 (1.09±0.07) (p=0.0005). This increase was equivalent to that observed using the HVEM immune activator, LIGHT (Fig.1B). In line with these results, immunofluorescence staining of primary monocytes showed that HVEM5 treatment increased the nuclear translocation of the NF-kB p65 transcriptional subunit, which was greater than that of LIGHT-treated cells (Fig.1B). Furthermore, HVEM5 generated with a mouse-reactive Fc fragment induced a significantly longer overall survival (median 22 days) and tumor reduction in an NCr nude mouse model when injected intravenously twice a week (3 mg/kg, Mon-Fri), whereas the median survival was 15 days in the IgG-treated control animals (p=0.01) (Fig.1A; right trace). Further in vivo studies in HVEM/BTLA double humanized immune competent animal models and in HVEM knock-out mouse models are ongoing, and the results will be presented at the meeting. To our knowledge, the present work is the first to report that MM cells ubiquitously express HVEM, which could be exploited as a novel therapeutic opportunity to not only target it as an immune checkpoint, but also as a direct MM-targeting strategy.

Modulation of the Btla-HVEM Axis to Enhance CAR T Cell Immunotherapy Against Cancer

Introduction: The efficacy of adoptive T cell immunotherapies against cancer, such as chimeric antigen receptor (CAR) T cells, is severely blunted by the immunosuppressive tumor microenvironment (TME). We sought to investigate the role of the TME in cancer resistance to effector T cells in order to define actionable targets to enhance CAR T cell immunotherapies. We initially used Hodgkin lymphoma (HL) as an ideal tumor model since it is characterized by a TME that is profoundly infiltrated by immunosuppressive cells, and then we expanded our findings to multiple cancer models. We first sought to identify the dominant interactions of immunosuppressive cellular compartments and effector T cells by analyzing single-cell RNA sequencing data on a total of 26 (4 exploratory + 22 validation) HL patient tumor biopsies. Using the CellPhoneDB algorithm, we inferred that the ligand B- and T-lymphocyte attenuator (BTLA) on effector T cells and the receptor Herpesvirus entry mediator (HVEM, TNFRSF14) on immunosuppressive cells (e.g., regulatory T cells, monocytes) strongly interact in the TME and promote T cell dysfunction ( Fig 1a). Akin to the canonical checkpoint PD1, BTLA recruits two potent tyrosine phosphatases, SHP-1 and SHP-2, to disable early T cell activation. Thus, we rationalized that BTLA expression on T cells might reduce their anti-tumor function. We hypothesized that deleting BTLA in CAR T cells would abolish BTLA-HVEM trans interactions at the immunological synapse and unleash the cytotoxic potential of CAR T cells. Methods and Results: We first generated BTLA KO anti-CD30 CAR T (CART30) cells against HL. To test their function in vivo, 15x10 6 HDLM-2 (CD30+HVEM+ HL) cells were subcutaneously implanted into NSG mice on day 0, and on day 62, 3x10 5 CAR30+ T cells were infused intravenously. Our results demonstrated that BTLA KO significantly enhances the function of anti-CD30 CAR T cells in HVEM+ HL ( Fig 1b), as assessed via tumor size (caliper) and CART30 expansion in the peripheral blood (flow cytometry). Additionally, we generated BTLA KO 4-1BBζ CART19 cells, which showed greater in vivo anti-tumor function in a subcutaneous tumor model of DLBCL (CD19+ HVEM+ OCI-Ly18). Serum collected from OCI-Ly18-bearing NSG mice infused with BTLA KO CART19 was enriched in effector cytokines (e.g., TNF, IFNγ, IL-2) as measured by Luminex. We then extended these findings into HVEM+ solid tumor models. BTLA KO improved tumor control in vitro in short-term killing experiments (Incucyte SX5) for both CAR and TCR T cells, respectively directed against prostate cancer (HER2+ PC-3) and melanoma (GP-100+ DM-6). Importantly, we demonstrated that BTLA KO in primary BALB/c-derived murine CAR T cells enhances tumor control in A20 murine lymphoma. In this model, BTLA KO tumor-infiltrating CAR T cells showed substantially reduced exhaustion in the TME relative to wild-type CAR T cells. Mechanistically, we showed that targeted mutations in BTLA intracellular tyrosine motifs effectively reduce the recruitment of SHP-1/2 and preserve the docking domain of the pro-stimulatory Grb2, thus maintaining high NFAT signaling and increased persistence in vivo. These effects were dependent on the expression of HVEM on tumor cells. Finally, we found that high BTLA RNA expression in tisagenlecleucel infusion products correlates with poor response to treatment in patients with DLBCL and FL (NCT02030834). Conclusion: Our results reveal a critical role of the BTLA-HVEM axis in inhibiting CAR T cell function, and demonstrate that CRISPR-Cas9 deletion of BTLA leads to enhanced anti-tumor efficacy in multiple models of cancer. The key mechanism is the reduction of SHP-1/2 recruitment and the consequent increase in CAR T cell activation. The results of this study will be translated into a first in human clinical trial of BTLA-deficient CAR T cells for relapsed or refractory cancer.