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.

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.

scholarly journals In vitro effects of Staphylococcus aureus enterotoxin C3 on T cell activation, proliferation and cytokine production

2017 ◽  
Vol 16 (4) ◽  
pp. 4744-4750 ◽  
Author(s):  
Yixin Xie ◽  
Min Wang ◽  
Zhihui Dong ◽  
Huan Song ◽  
Lianping Li ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
T Cell ◽  
T Cell Activation ◽  
Cell Activation ◽  
Cytokine Production ◽  
In Vitro Effects

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

scholarly journals Regulation of T Cell-Mediated Hepatic Inflammation by Adiponectin and Leptin

Endocrinology ◽  
2005 ◽  
Vol 146 (5) ◽  
pp. 2157-2164 ◽  
Author(s):  
Joseph A. Sennello ◽  
Raja Fayad ◽  
Alison M. Morris ◽  
Robert H. Eckel ◽  
Esra Asilmaz ◽  
...  
Keyword(s):  
T Cell ◽  
T Cell Activation ◽  
Cell Activation ◽  
Cytokine Production ◽  
Contrast Administration ◽  
Cytokine Levels ◽  
Hepatotoxic Effect ◽  
Killer T Cells

Abstract Concanavalin A-induced hepatotoxicity was compared in lipodystrophic aP2-nSREBP-1c transgenic mice (LD mice) lacking adipose tissue, obese leptin-deficient ob/ob mice, and lean wild-type (WT) mice. Serum leptin and adiponectin were low in LD mice, whereas ob/ob mice had undetectable leptin, but high adiponectin. Protection from hepatotoxicity was observed in ob/ob, but not in LD mice, despite low cytokine levels and reduced T cell activation and hepatic natural killer T cells in both groups. Administration of adiponectin protected LD mice from hepatotoxicity without altering cytokine levels. In contrast, administration of leptin heightened disease susceptibility by restoring cytokine production. Neutralization of TNFα protected LD mice from liver damage. Increased in vivo susceptibility to the hepatotoxic effect of TNFα was observed in LD mice. In vitro, adiponectin protected primary hepatocytes from TNFα-induced death, whereas leptin had no protective effect. In conclusion, although leptin increases susceptibility to hepatotoxicity by regulating cytokine production and T cell activation, adiponectin protects hepatocytes from TNFα-induced death.

scholarly journals A Novel T Cell-Engaging Bispecific Antibody for Treating Mesothelin-Positive Solid Tumors

Biomolecules ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 399
Author(s):  
Aerin Yoon ◽  
Shinai Lee ◽  
Sua Lee ◽  
Sojung Lim ◽  
Yong-Yea Park ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Solid Tumors ◽  
T Cell Activation ◽  
Target Cell ◽  
Cell Activation ◽  
Cell Killing ◽  
Bispecific Antibodies ◽  
Target Cells

As mesothelin is overexpressed in various types of cancer, it is an attractive target for therapeutic antibodies. T-cell bispecific antibodies bind to target cells and engage T cells via binding to CD3, resulting in target cell killing by T-cell activation. However, the affinity of the CD3-binding arm may influence CD3-mediated plasma clearance or antibody trapping in T-cell-containing tissues. This may then affect the biodistribution of bispecific antibodies. In this study, we used scFab and knob-into-hole technologies to construct novel IgG-based 1 + 1 MG1122-A and 2 + 1 MG1122-B bispecific antibodies against mesothelin and CD3ε. MG1122-B was designed to be bivalent to mesothelin and monovalent to CD3ε, using a 2 + 1 head-to-tail format. Activities of the two antibodies were evaluated in mesothelin-positive tumor cells in vitro and xenograft models in vivo. Although both antibodies exhibited target cell killing efficacy and produced regression of xenograft tumors with CD8+ T-cell infiltration, the antitumor efficacy of MG1122-B was significantly higher. MG1122-B may improve tumor targeting because of its bivalency for tumor antigen. It may also reduce systemic toxicity by limiting the activation of circulating T cells. Thus, MG1122-B may be useful for treating mesothelin-positive solid tumors.

scholarly journals 697 Tumor-targeted CD28 costimulatory bispecific antibodies enhance T cell activation in solid tumors

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A739-A739
Author(s):  
Michael Hedvat ◽  
Veronica Zeng ◽  
Juan Diaz ◽  
Christine Bonzon ◽  
Kendra Avery ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Solid Tumors ◽  
Cancer Cell ◽  
T Cell Activation ◽  
Cell Activation ◽  
Bispecific Antibodies ◽  
Anti Tumor Activity

BackgroundT cells in the tumor micro-environment require TCR/MHC engagement and co-stimulatory receptor engagement to achieve complete activation. Solid tumors often lack expression of CD28 ligands, so we hypothesized that activation of CD28 signaling could be beneficial in solid tumors. We designed tumor-associated-antigen (TAA) x CD28 bispecific antibodies that conditionally costimulate CD28 only in the presence of TAA and TCR engagement. Clinical application of this class of antibodies has potential to enhance activity of either anti-PD(L)1 antibodies or TAA x CD3 T cell engagers.MethodsWe designed a stability and affinity optimized anti-CD28 antibody that can be paired with TAA of choice to engage CD28 monovalently using Xencor’s XmAb 2+1 and 1+1 platforms. In vitro T cell activation with these bispecifics was measured by T cell proliferation, cytokine production, and cytotoxicity, in co-cultures of human cancer cell lines mixed with primary human CD3-stimulated T cells. In vitro activity was validated in a CMV recall assay measuring CMV+ T cell proliferation of CMV+ PBMC co-cultured with cancer cell lines ectopically treated with pp65-derived NLV-peptide. In vivo anti-tumor and T cell proliferative activity of B7H3 x CD28 bispecific antibodies were determined in tumor-bearing huPBMC-NSG mice treated simultaneously with TAA x CD3 bispecific antibody. In vivo activity of PDL1 x CD28 antibodies was determined with hCD28 KI mice inoculated with MC38 tumors expressing hPDL1-antigen. Finally, safety and tolerability of B7H3 x CD28 and PDL1 x CD28 was determined in cynomolgus monkeys.ResultsB7H3 x CD28 and PDL1 x CD28 antibodies enhanced T cell degranulation, cytokine secretion, and cancer cell cytotoxicity in concert with CD3 stimulation only in the presence of target antigen. B7H3 x CD28, alone or in combination with anti-PD1 antibody, enhanced proliferation of CMV+ T cells recognizing cancer cells loaded with pp65-derived NLV peptide. PDL1 x CD28 also enhanced CMV+ cell expansion but did not synergize with anti-PD1 antibody treatment. B7H3 x CD28 significantly enhanced in vivo anti-tumor activity of TAA x CD3 antibodies while also promoting greater T cell expansion. In hCD28 mice inoculated with MC38 tumors expressing hPDL1, PDL1 x CD28 antibody inhibited tumor growth greater than an anti-PDL1 antibody alone. B7H3 x CD28 and PDL1 x CD28 were well tolerated in cynomolgus monkeys.ConclusionsB7H3 x CD28 and PDL1 x CD28 bispecific antibodies show promising anti-tumor activity and warrant further development.

P155 THERAPEUTIC EFFECT OF OPS-2071 ON HEALING OF T CELL-MEDIATED COLITIS, A MURINE MODEL OF CROHN’S DISEASE, WITH ANTI-INFLAMMATORY AND ANTIBACTERIAL ACTIVITY

2020 ◽  
Vol 26 (Supplement_1) ◽  
pp. S7-S8
Author(s):  
Hiroko Takagi ◽  
Masayoshi Sato ◽  
Kazuyuki Fujii ◽  
Isao Shibuya ◽  
Daisuke Oka ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
T Cell ◽  
T Cell Activation ◽  
Cell Activation ◽  
Cytokine Production ◽  
Human Peripheral Blood ◽  
Vitro Activity ◽  
In Vitro Activity ◽  
Inflammatory Index

Abstract Background Crohn’s disease (CD) is a form of chronic inflammatory bowel disease (IBD). Although CD is an immune-mediated condition of unknown etiology, many studies suggested that abnormal immune responses against certain intestinal bacteria may trigger development of chronic inflammation. The T cell-mediated colitis model is a well characterized adaptive transfer murine model of chronic small bowel and colonic inflammation that resembles human CD (e.g., diarrhea, a heavily inflamed colon, loss of mucus from goblet cells, Th1/Th17 dominated cytokine profile). OPS-2071, a novel agent synthesized by Otsuka Pharmaceutical Co., Ltd, has broad and strong antibacterial activity with low systemic absorption. In this study, we have evaluated the therapeutic effect of OPS-2071 on murine T cell-mediated colitis and in vitro activity on T cell activation, cytokine production and antibacterial activity. Methods T cell-mediated colitis was induced via naive T cell (CD4+CD62L+CD44-) injection into T and B cell deficient recipient mice. Two weeks following T cell transfer, OPS-2071 or vehicle solution was administered orally for 3 weeks, followed by harvesting of colon tissue and assessment of efficacy evaluation by histological score and inflammatory index (colon weight/ length). In vitro inhibitory action for TNF-α production was assayed by ELISA using LPS-stimulated human peripheral blood cells. The effect on T cell activation and cytokine production (TNF-α, IFN-γ), was examined using human peripheral blood mononuclear cells and, mouse spleen which were stimulated by anti-CD2/CD3/CD28 antibody-loaded beads. In vitro activity against bacteria considered to be the cause of IBD was also tested. Results In the murine T cell transfer model, OPS-2071 significantly reduced both histological score (control: 9.2, OPS: 2.7, p<0.001) and inflammatory index (control: 54.7±2.2 mg/cm, OPS: 27.8±1.7 mg/cm, p<0.001) at a dose of 10 mg/kg. In the in vitro experiments, OPS-2071 suppressed TNF-a production produced by LPS in human whole blood dose-dependently. OPS-2071 also suppressed human and mouse T cell activation and cytokine production and suppressed T cell proliferation. At high OPS-2071 concentrations, these effects were comparable to prednisolone. The Minimum Inhibitory Concentration against IBD related bacteria for OPS-2071, ciprofloxacin, and metronidazole were 0.015 - 0.5, 0.25 - 8, and 0.03 - >128 mg/mL, respectively. Conclusion OPS-2071 demonstrated significant therapeutic effects on colon inflammation in the murine T cell-medicated colitis model, suppressed TNF-a production in vitro and showed in vitro activity against bacteria related to CD. The dual effect of anti-inflammatory effects and antibacterial activity of the novel agent OPS-2071 demonstrated in this study, provide rationale for exploring the impact of this compound on human CD in clinical trials.

Sign in / Sign up

Export Citation Format

Share Document