scholarly journals Suppression of human T cell activation by derivatives of glycerol monolaurate

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Micaela G. Fosdick ◽  
Pratik Rajesh Chheda ◽  
Phuong M. Tran ◽  
Alex Wolff ◽  
Ronal Peralta ◽  
...  
Keyword(s):  
T Cell ◽  
Calcium Signaling ◽  
T Cell Activation ◽  
Cell Activation ◽  
Cytokine Production ◽  
Acyl Chain ◽  
Antimicrobial Properties ◽  
Head Group ◽  
Human T Cell ◽  
Ester Linkage

AbstractGlycerol monolaurate (GML), a naturally occurring monoglyceride, is widely used commercially for its antimicrobial properties. Interestingly, several studies have shown that GML not only has antimicrobial properties but is also an anti-inflammatory agent. GML inhibits peripheral blood mononuclear cell proliferation and inhibits T cell receptor (TCR)-induced signaling events. In this study, we perform an extensive structure activity relationship analysis to investigate the structural components of GML necessary for its suppression of human T cell activation. Human T cells were treated with analogs of GML, differing in acyl chain length, head group, linkage of acyl chain, and number of laurate groups. Treated cells were then tested for changes in membrane dynamics, LAT clustering, calcium signaling, and cytokine production. We found that an acyl chain with 12–14 carbons, a polar head group, an ester linkage, and a single laurate group at any position are all necessary for GML to inhibit protein clustering, calcium signaling, and cytokine production. Removing the glycerol head group or replacing the ester linkage with a nitrogen prevented derivative-mediated inhibition of protein cluster formation and calcium signaling, while still inhibiting TCR-induced cytokine production. These findings expand our current understanding of the mechanisms of action of GML and the of GML needed to function as a novel immunosuppressant.

scholarly journals Farnesyltransferase inhibitors inhibit T-cell cytokine production at the posttranscriptional level

Blood ◽  
2007 ◽  
Vol 110 (6) ◽  
pp. 1982-1988 ◽  
Author(s):  
Reinhard E. Marks ◽  
Allen W. Ho ◽  
Christian Robbel ◽  
Todd Kuna ◽  
Seth Berk ◽  
...  
Keyword(s):  
T Cell ◽  
T Cell Activation ◽  
Intracellular Signaling ◽  
Map Kinases ◽  
Cell Activation ◽  
Cytokine Production ◽  
Immunosuppressive Agents ◽  
Farnesyltransferase Inhibitors ◽  
Human T Cell ◽  
Posttranscriptional Level

Abstract Several cytoplasmic proteins, such as GTPases of the Ras family, containing a C-terminal CAAX motif are prenylated by farnesyltransferase to facilitate localization to cellular membranes where activation occurs. Farnesyltransferase inhibitors (FTIs) interfere with this farnesylation process, thereby preventing proper membrane localization and rendering the proteins unavailable for activation. Currently, FTIs are being explored as antineoplastic agents for the treatment of several malignancies. However, since farnesylated proteins like Ras are also involved in intracellular signaling in lymphocytes, FTIs might interfere with T-cell activation. Based on this hypothesis we examined the effect of several FTIs on cytokine production in response to anti-CD3 + anti-CD28 monoclonal antibodies or PMA + ionomycin. Murine Th1 and Th2 clones, stimulated in the presence of FTIs, showed a dose-dependent reduction of lineage-specific cytokine secretion (IFN-γ, IL-2, IL-4, IL-5). However, no inhibition of ERK or JNK MAP kinases was observed, nor was induction of cytokine mRNA affected. Rather, intracellular cytokine protein synthesis was blocked. Inhibition of human T-cell INF-γ production also was observed, correlating with reduced phosphorylation of p70S6K. These results indicate that FTIs inhibit T-cell activation at the posttranscriptional level and also suggest that they may have potential as novel immunosuppressive agents.

scholarly journals GFP Affects Human T Cell Activation and Cytokine Production following In Vitro Stimulation

PLoS ONE ◽  
2013 ◽  
Vol 8 (4) ◽  
pp. e50068 ◽  
Author(s):  
Kristi A. Koelsch ◽  
YuJing Wang ◽  
Jacen S. Maier-Moore ◽  
Amr H. Sawalha ◽  
Jonathan D. Wren
Keyword(s):  
T Cell ◽  
T Cell Activation ◽  
Cell Activation ◽  
Cytokine Production ◽  
Human T Cell

613 HER2-XPAT, a novel protease-activatable prodrug T cell engager (TCE), with potent T-cell activation and efficacy in solid tumors and large predicted safety margins in non-human primate (NHP)

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A649-A649
Author(s):  
Fiore Cattaruzza ◽  
Ayesha Nazeer ◽  
Zachary Lange ◽  
Caitlin Koski ◽  
Mikhail Hammond ◽  
...  
Keyword(s):  
T Cell ◽  
Solid Tumors ◽  
T Cell Activation ◽  
Cell Activation ◽  
Cytokine Production ◽  
Antigenic Specificity ◽  
The Core ◽  
Protease Cleavage ◽  
Safety Margins

BackgroundTCEs are effective in leukemias but have been challenging in solid tumors due to on-target, off-tumor toxicity. Attempts to circumvent CRS include step-up dosing and/or complex designs but are unsuccessful due to toxicity and/or enhanced immunogenicity. HER2-XPAT, or XTENylated Protease-Activated bispecific T-Cell Engager, is a prodrug TCE that exploits the protease activity present in tumors vs. healthy tissue to expand the therapeutic index (TI). The core of the HER2-XPAT (PAT) consists of 2 tandem scFvs targeting CD3 and HER2. Attached to the core, two unstructured polypeptide masks (XTEN) sterically reduce target engagement and extend T1/2. Protease cleavage sites at the base of the XTEN masks enable proteolytic activation of XPATs in the tumor microenvironment, unleashing a potent TCE with short T1/2, further improving the TI. HER2-XPAT, a tumor protease-activatable prodrug with wide safety margins, can co-opt T-cells regardless of antigenic specificity to induce T-cell killing of HER2+ tumors.MethodsPreclinical studies were conducted to characterize the activity of HER2-XPAT, HER2-PAT (cleaved XPAT), and HER2-NonClv (a non-cleavable XPAT) for cytotoxicity in vitro, for anti-tumor efficacy in xenograft models, and for safety in NHPs.ResultsHER2-PAT demonstrated potent in vitro T-cell cytotoxicity (EC50 1-2pM) and target-dependent T-cell activation and cytokine production by hPBMCs. HER2-XPAT provided up to 14,000-fold protection against killing of HER2 tumor cells and no cytotoxicity against cardiomyocytes up to 1uM. In vivo, HER2-XPAT induced complete tumor regressions in BT-474 tumors with equimolar dosing to HER2-PAT, whereas HER2-NonClv had no efficacy, supporting requirement of protease cleavage for T-cell activity. In NHP, HER2-XPAT has been dose-escalated safely up to 42mg/kg (MTD). HER2-XPAT demonstrated early T-cell margination at 2 mg/kg but largely spared CRS, cytokine production, and tissue toxicity up to 42 mg/kg. PK profiles of HER2-XPAT and HER2-NonClv were comparable, consistent with ex vivo stability for cleavage when incubated in cancer pts plasma for 7 days at 37°C. HER2-PAT by continuous infusion induced lethal CRS and cytokine spikes at 0.3 mg/kg/d but was tolerated at 0.25 mg/kg/d, providing HER2-XPAT with >1300-fold protection in tolerability vs. HER2-PAT, >4 logs over cytotoxicity EC50s for HER2 cell lines, and a 20-fold safety margin over the dose required for pharmacodynamic activity.ConclusionsHER2-XPAT is a potent prodrug TCE with no CRS and a wide TI based on NHPs. With XTEN’s clinical data demonstrating low immunogenicity, the XPATs are a promising solution. IND studies are ongoing. Additional PK/PD, cytokines, safety, and efficacy data will be presented.

HUMAN T-CELL ACTIVATION IS AUGMENTED BY MONOCLONAL ANTIBODY TO IgD

1982 ◽  
Vol 399 (1 Immunoglobuli) ◽  
pp. 227-237
Author(s):  
Denis R. Burger ◽  
David Regan ◽  
Karen Williams ◽  
Gerrie Leslie
Keyword(s):  
Monoclonal Antibody ◽  
T Cell ◽  
T Cell Activation ◽  
Cell Activation ◽  
Human T Cell

107 Effects of IL-2 and IL-15 on the proliferative and antitumor capacities of allogeneic CD20 CAR-engineered γδ T cells in a 3D B cell lymphoma spheroid assay

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A119-A119
Author(s):  
Lu Bai ◽  
Kevin Nishimoto ◽  
Mustafa Turkoz ◽  
Marissa Herrman ◽  
Jason Romero ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cell ◽  
T Cell Activation ◽  
Cell Activation ◽  
Cytokine Production ◽  
Γδ T Cells ◽  
Γδ T Cell ◽  
Car T

BackgroundAutologous chimeric antigen receptor (CAR) T cells have been shown to be efficacious for the treatment of B cell malignancies; however, widespread adoption and application of CAR T cell products still face a number of challenges. To overcome these challenges, Adicet Bio is developing an allogeneic γδ T cell-based CAR T cell platform, which capitalizes on the intrinsic abilities of Vδ1 γδ T cells to recognize and kill transformed cells in an MHC-unrestricted manner, to migrate to epithelial tissues, and to function in hypoxic conditions. To gain a better understanding of the requirements for optimal intratumoral CAR Vδ1 γδ T cell activation, proliferation, and differentiation, we developed a three-dimensional (3D) tumor spheroid assay, in which tumor cells acquire the structural organization of a solid tumor and establish a microenvironment that has oxygen and nutrient gradients. Moreover, through the addition of cytokines and/or tumor stromal cell types, the spheroid microenvironment can be modified to reflect hot or cold tumors. Here, we report on the use of a 3D CD20+ Raji lymphoma spheroid assay to evaluate the effects of IL-2 and IL-15, positive regulators of T cell homeostasis and differentiation, on the proliferative and antitumor capacities of CD20 CAR Vδ1 γδ T cells.MethodsMolecular, phenotypic, and functional profiling were performed to characterize the in vitro dynamics of the intraspheroid CD20 CAR Vδ1 γδ T cell response to target antigen in the presence of IL-2, IL-15, or no added cytokine.ResultsWhen compared to no added cytokine, the addition of IL-2 or IL-15 enhanced CD20 CAR Vδ1 γδ T cell activation, proliferation, survival, and cytokine production in a dose-dependent manner but were only able to alter the kinetics of Raji cell killing at low effector to target ratios. Notably, differential gene expression analysis using NanoString nCounter® Technology confirmed the positive effects of IL-2 or IL-15 on CAR-activated Vδ1 γδ T cells as evidenced by the upregulation of genes involved in activation, cell cycle, mitochondrial biogenesis, cytotoxicity, and cytokine production.ConclusionsTogether, these results not only show that the addition of IL-2 or IL-15 can potentiate CD20 CAR Vδ1 γδ T cell activation, proliferation, survival, and differentiation into antitumor effectors but also highlight the utility of the 3D spheroid assay as a high throughput in vitro method for assessing and predicting CAR Vδ1 γδ T cell activation, proliferation, survival, and differentiation in hot and cold tumors.

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