Abstract 3266: BND-22, a first-in-class, anti-ILT2 monoclonal antibody inhibits the immunosuppressive effects of HLA-G and enhances anti-tumor activity of immune cells in preclinical in vitro, ex vivo, and in vivo models

Author(s):  
Ilana Mandel ◽  
Dana Haves ◽  
Ilana Goldshtein ◽  
Tsuri Peretz ◽  
Dror Alishekevitz ◽  
...  
2017 ◽  
Vol 35 ◽  
pp. 46-47 ◽  
Author(s):  
P. Pérez-Galán ◽  
A. Vidal-Crespo ◽  
A. Matas-Céspedes ◽  
V. Rodriguez ◽  
C. Rossi ◽  
...  

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A113-A113
Author(s):  
Mireia Bachiller García ◽  
Lorena Pérez-Amill ◽  
Anthony Battram ◽  
Alvaro Urbano-Ispizua ◽  
Beatriz Martín-Antonio

BackgroundMultiple myeloma (MM) remains an incurable hematological malignancy where a proportion of patients relapse or become refractory to current treatments. Administration of autologous T cells modified with a chimeric antigen receptor (CAR) against B cell maturation antigen (BCMA) has achieved high percentages of complete responses. Unfortunately, the lack of persistence of CART-BCMA cells in the patient leads to relapses. On the other side, cord-blood derived natural killer cells (CB-NK) is an off-the-shelf cellular immunotherapy option to treat cancer patients with high potential due to their anti-tumor activity. However, clinical results in patients up to date have been sub-optimal. Whereas CB-NK are innate immune cells and their anti-tumor activity is developed in a few hours, CART cells are adaptive immune cells and their activity develops at later time points. Moreover, we previously described that CB-NK secrete inflammatory proteins that promote the early formation of tumor-immune cell clusters bringing cells into close contact and thus, facilitating the anti-tumor activity of T cells. Therefore, we hypothesized that the addition of a small number of CB-NK to CART cells would improve the anti-tumor activity and increase the persistence of CART cells.MethodsT cells transduced with a humanized CAR against BCMA and CB-NK were employed at 1:0.5 (CART:CB-NK) ratio. Cytotoxicity assays, activation markers and immune-tumor cell cluster formation were evaluated by flow cytometry and fluorescence microscopy. In vivo models were performed in NSG mice.ResultsThe addition of CB-NK to CART cells demonstrated higher anti-MM efficacy at low E:T ratios during the first 24h and in long-term cytotoxicity assays, where the addition of CB-NK to CART cells achieved complete removal of tumor cells. Analysis of activation marker CD69 and CD107a degranulation from 4h to 24h of co-culturing proved differences only at 4h, where CD69 and CD107a in CART cells were increased when CB-NK were present. Moreover, CB-NK accelerated an increased formation of CART-tumor cell clusters facilitating the removal of MM cells. Of note, CB-NK addition did not increase total TNFα and IFNγ production. Finally, an in vivo model of advanced MM with consecutive challenge to MM cells evidenced that the addition of CB-NK achieved the highest efficacy of the treatment.ConclusionsOur results suggest that the addition of ‘off-the-shelf’ CB-NK to CART cells leads to a faster and earlier immune response of CART cells with higher long-term maintenance of the anti-tumor response, suggesting this combinatorial therapy as an attractive immunotherapy option for MM patients.


2018 ◽  
Vol 315 (5) ◽  
pp. C653-C663 ◽  
Author(s):  
Kasin Yadunandam Anandam ◽  
Omar A. Alwan ◽  
Veedamali S. Subramanian ◽  
Padmanabhan Srinivasan ◽  
Rubina Kapadia ◽  
...  

Riboflavin (RF), is essential for normal cellular metabolism/function. Intestinal RF absorption occurs via a specific carrier-mediated process that involves the apical transporter RFVT-3 ( SLC52A3) and the basolateral RFVT-1 (SLC52A1). Previously, we characterized different cellular/molecular aspects of the intestinal RF uptake process, but nothing is known about the effect of proinflammatory cytokines on the uptake event. We addressed this issue using in vitro, ex vivo, and in vivo models. First, we determined the level of mRNA expression of the human (h)RFVT-3 and hRFVT-1 in intestinal tissue of patients with inflammatory bowel disease (IBD) and observed a markedly lower level compared with controls. In the in vitro model, exposing Caco-2 cells to tumor necrosis factor-α (TNF-α) led to a significant inhibition in RF uptake, an effect that was abrogated upon knocking down TNF receptor 1 (TNFR1). The inhibition in RF uptake was associated with a significant reduction in the expression of hRFVT-3 and -1 protein and mRNA levels, as well as in the activity of the SLC52A3 and SLC52A1 promoters. The latter effects appear to involve Sp1 and NF-κB sites in these promoters. Similarly, exposure of mouse small intestinal enteroids and wild-type mice to TNF-α led to a significant inhibition in physiological and molecular parameters of intestinal RF uptake. Collectively, these findings demonstrate that exposure of intestinal epithelial cells to TNF-α leads to inhibition in RF uptake and that this effect is mediated, at least in part, via transcriptional mechanism(s). These findings may explain the significantly low RF levels observed in patients with IBD.


Author(s):  
Noemi Vanerio ◽  
Marco Stijnen ◽  
Bas A. J. M. de Mol ◽  
Linda M. Kock

Abstract Ex vivo systems represent important models to study vascular biology and to test medical devices, combining the advantages of in vitro and in vivo models such as controllability of parameters and the presence of biological response, respectively. The aim of this study was to develop a comprehensive ex vivo vascular bioreactor to long-term culture and study the behavior of native blood vessels under physiologically relevant conditions. The system was designed to allow for physiological mechanical loading in terms of pulsatile hemodynamics, shear stress, and longitudinal prestretch and ultrasound imaging for vessel diameter and morphology evaluation. In this first experience, porcine carotid arteries (n = 4) from slaughterhouse animals were cultured in the platform for 10 days at physiological temperature, CO2 and humidity using medium with blood-mimicking viscosity, components, and stability of composition. As expected, a significant increase in vessel diameter was observed during culture. Flow rate was adjusted according to diameter values to reproduce and maintain physiological shear stress, while pressure was kept physiological. Ultrasound imaging showed that the morphology and structure of cultured arteries were comparable to in vivo. Histological analyses showed preserved endothelium and extracellular matrix and neointimal tissue growth over 10 days of culture. In conclusion, we have developed a comprehensive pulsatile system in which a native blood vessel can be cultured under physiological conditions. The present model represents a significant step toward ex vivo testing of vascular therapies, devices, drug interaction, and as basis for further model developments.


Biomolecules ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 675 ◽  
Author(s):  
Mariana Amaral ◽  
Ana Sofia Martins ◽  
José Catarino ◽  
Pedro Faísca ◽  
Pradeep Kumar ◽  
...  

Currently, insulin can only be administered through the subcutaneous route. Due to the flaws associated with this route, it is of interest to orally deliver this drug. However, insulin delivered orally has several barriers to overcome as it is degraded by the stomach’s low pH, enzymatic content, and poor absorption in the gastrointestinal tract. Polymers with marine source like chitosan are commonly used in nanotechnology and drug delivery due to their biocompatibility and special features. This work focuses on the preparation and characterization of mucoadhesive insulin-loaded polymeric nanoparticles. Results showed a suitable mean size for oral administration (<600 nm by dynamic laser scattering), spherical shape, encapsulation efficiency (59.8%), and high recovery yield (80.6%). Circular dichroism spectroscopy demonstrated that protein retained its secondary structure after encapsulation. Moreover, the mucoadhesive potential of the nanoparticles was assessed in silico and the results, corroborated with ex-vivo experiments, showed that using chitosan strongly increases mucoadhesion. Besides, in vitro and in vivo safety assessment of the final formulation were performed, showing no toxicity. Lastly, the insulin-loaded nanoparticles were effective in reducing diabetic rats’ glycemia. Overall, the coating of insulin-loaded nanoparticles with chitosan represents a potentially safe and promising approach to protect insulin and enhance peroral delivery.


2015 ◽  
Vol 2015 ◽  
pp. 1-15 ◽  
Author(s):  
Kazuko Kobayashi ◽  
Takanori Sasaki ◽  
Fumiaki Takenaka ◽  
Hiromasa Yakushiji ◽  
Yoshihiro Fujii ◽  
...  

Mesothelin (MSLN) is a 40-kDa cell differentiation-associated glycoprotein appearing with carcinogenesis and is highly expressed in many human cancers, including the majority of pancreatic adenocarcinomas, ovarian cancers, and mesotheliomas, while its expression in normal tissue is limited to mesothelial cells lining the pleura, pericardium, and peritoneum. Clone 11-25 is a murine hybridoma secreting monoclonal antibody (mAb) against human MSLN. In this study, we applied the 11-25 mAb toin vivoimaging to detect MSLN-expressing tumors. Inin vitroandex vivoimmunochemical studies, we demonstrated specificity of 11-25 mAb to membranous MSLN expressed on several pancreatic cancer cells. We showed the accumulation of Alexa Fluor 750-labeled 11-25 mAb in MSLN-expressing tumor xenografts in athymic nude mice. Then, 11-25 mAb was labeled with64Cu via a chelating agent DOTA and was used in bothin vitrocell binding assay andin vivopositron emission tomography (PET) imaging in the tumor-bearing mice. We confirmed that64Cu-labeled 11-25 mAb highly accumulated in MSLN-expressing tumors as compared to MSLN-negative ones. The64Cu-labeled 11-25 mAb is potentially useful as a PET probe capable of being used for wide range of tumors, rather than18F-FDG that occasionally provides nonspecific accumulation into the inflammatory lesions.


Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 2273-2273
Author(s):  
Nikoleta Sachini ◽  
Asma Jabeen ◽  
Patrick H van Berkel ◽  
Francesca Zammarchi

Abstract Loncastuximab tesirine-lpyl (formerly ADCT-402) is an antibody-drug conjugate (ADC) comprising a humanised anti-CD19 monoclonal antibody conjugated to the pyrrolobenzodiazepine (PBD) dimer-based payload tesirine. Once bound to CD19 on the cell membrane, loncastuximab tesirine is rapidly internalised and the released PBD dimer warhead causes interstrand DNA crosslinks which ultimately trigger cell death. Pre-clinically, loncastuximab tesirine has shown potent and specific anti-tumor activity in lymphoma models both as single agent and in combination with other approved drugs, like venetoclax, idelalisib and bendamustine (Zammarchi, Corbett et al. 2018, Tarantelli, Spriano et al. 2019). Loncastuximab tesirine has been recently approved by the United States Food and Drug Administration (FDA) for the treatment of relapsed or refractory (r/r) diffuse large B-cell lymphoma (DLBCL) and it is currently being tested in multiple clinical trials, either as monotherapy or in combination with other anti-lymphoma drugs. Polatuzumab vedotin is an ADC composed of a humanized anti-CD79b monoclonal antibody conjugated to monomethyl auristatin E (vcMMAE) and it is approved by the FDA for treatment of r/r DLBCL when used in combination with bendamustine and rituximab. Here, we investigated the in vitro and in vivo anti-tumor activity of loncastuximab tesirine combined with polatuzumab vedotin in pre-clinical models of non-Hodgkin lymphoma (NHL). In vitro, the combination of loncastuximab tesirine and polatuzumab vedotin was tested in three human-derived, CD19 and CD79b-positive NHL cell lines (WSU-DLCL2, TMD8 and Ramos) and it resulted in synergistic (TMD8 and Ramos) and additive (WSU-DLCL2) activity, as assessed by the Chou-Talalay method. Quantification of cell viability (propidium iodide [PI]-negative and Annexin V-negative) and early/late apoptosis (Annexin V-positive and PI-negative/ Annexin V-positive and-PI positive) on TMD8 and Ramos cells treated with loncastuximab tesirine, polatuzumab vedotin or the combination of the two agents showed a significant reduction of viable cells accompanied by an increase in apoptotic cells in the combination setting compared to the single agents. In vivo, loncastuximab tesirine was tested either alone (0.25 or 0.5 mg/kg, single dose) or in combination with polatuzumab vedotin (1 mg/kg, single dose) in the WSU-DLCL2 xenograft model. At the highest dose of loncastuximab tesirine, combination with polatuzumab vedotin resulted in improved anti-tumor activity and superior response rate compared to the 2 agents in monotherapy. All treatment regimens were well tolerated by the mice, as assessed by body weight measurements and frequent observation for signs of treatment-related side effects. In conclusion, the combination of loncastuximab tesirine and polatuzumab vedotin resulted in improved anti-tumor activity both in vitro and in vivo in lymphoma preclinical models and it was well tolerated. Altogether, these novel pre-clinical data warrant translation of the combination of loncastuximab tesirine and polatuzumab vedotin into the clinic for the treatment of NHL. Disclosures Sachini: ADC Therapeutics: Current Employment, Current equity holder in publicly-traded company. Jabeen: ADC Therapeutics: Current Employment, Current equity holder in publicly-traded company. van Berkel: ADC Therapeutics: Current Employment, Current equity holder in publicly-traded company, Patents & Royalties. Zammarchi: ADC Therapeutics: Current Employment, Current equity holder in publicly-traded company, Patents & Royalties.


Genes ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1650
Author(s):  
Selvi C. Ersoy ◽  
Blake M. Hanson ◽  
Richard A. Proctor ◽  
Cesar A. Arias ◽  
Truc T. Tran ◽  
...  

Methicillin-resistant Staphylococcus aureus (MRSA) infections represent a difficult clinical treatment issue. Recently, a novel phenotype was discovered amongst selected MRSA which exhibited enhanced β-lactam susceptibility in vitro in the presence of NaHCO3 (termed ‘NaHCO3-responsiveness’). This increased β-lactam susceptibility phenotype has been verified in both ex vivo and in vivo models. Mechanistic studies to-date have implicated NaHCO3-mediated repression of genes involved in the production, as well as maturation, of the alternative penicillin-binding protein (PBP) 2a, a necessary component of MRSA β-lactam resistance. Herein, we utilized RNA-sequencing (RNA-seq) to identify genes that were differentially expressed in NaHCO3-responsive (MRSA 11/11) vs. non-responsive (COL) strains, in the presence vs. absence of NaHCO3-β-lactam co-exposures. These investigations revealed that NaHCO3 selectively repressed the expression of a cadre of genes in strain 11/11 known to be a part of the sigB-sarA-agr regulon, as well as a number of genes involved in the anchoring of cell wall proteins in MRSA. Moreover, several genes related to autolysis, cell division, and cell wall biosynthesis/remodeling, were also selectively impacted by NaHCO3-OXA exposure in the NaHCO3-responsive strain MRSA 11/11. These outcomes provide an important framework for further studies to mechanistically verify the functional relevance of these genetic perturbations to the NaHCO3-responsiveness phenotype in MRSA.


Sign in / Sign up

Export Citation Format

Share Document