In Vivo Cytotoxicity by α-GalCer-transactivated NK Cells

Restrictions on the use of antibiotics in the poultry industry stimulate the development of alternative nutritional solutions to maintain or improve poultry health. This requires more insight in the modulatory effects of feed additives on the immune system and microbiota composition. Compounds known to influence the innate immune system and microbiota composition were selected and screened in vitro, in ovo, and in vivo. Among all compounds, 57 enhanced NK cell activation, 56 increased phagocytosis, and 22 increased NO production of the macrophage cell line HD11 in vitro. Based on these results, availability and regulatory status, six compounds were selected for further analysis. None of these compounds showed negative effects on growth, hatchability, and feed conversion in in ovo and in vivo studies. Based on the most interesting numerical results and highest future potential feasibility, two compounds were analyzed further. Administration of glucose oligosaccharide and long-chain glucomannan in vivo both enhanced activation of intraepithelial NK cells and led to increased relative abundance of lactic acid bacteria (LAB) amongst ileum and ceca microbiota after seven days of supplementation. Positive correlations between NK cell subsets and activation, and relative abundance of LAB suggest the involvement of microbiota in the modulation of the function of intraepithelial NK cells. This study identifies glucose oligosaccharide and long-chain glucomannan supplementation as effective nutritional strategies to modulate the intestinal microbiota composition and strengthen the intraepithelial innate immune system.

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A bispecific antibody agonist of the IL-2 heterodimeric receptor preferentially promotes in vivo expansion of CD8 and NK cells

Scientific Reports ◽

10.1038/s41598-021-90096-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Katherine E. Harris ◽

Kyle J. Lorentsen ◽

Harbani K. Malik-Chaudhry ◽

Kaitlyn Loughlin ◽

Harish Medlari Basappa ◽

...

Keyword(s):

T Cells ◽

Nk Cells ◽

Bispecific Antibody ◽

T Regulatory Cells ◽

Tumor Regression ◽

Interleukin 2 ◽

In Vivo Studies ◽

Preferential Binding

AbstractThe use of recombinant interleukin-2 (IL-2) as a therapeutic protein has been limited by significant toxicities despite its demonstrated ability to induce durable tumor-regression in cancer patients. The adverse events and limited efficacy of IL-2 treatment are due to the preferential binding of IL-2 to cells that express the high-affinity, trimeric receptor, IL-2Rαβγ such as endothelial cells and T-regulatory cells, respectively. Here, we describe a novel bispecific heavy-chain only antibody which binds to and activates signaling through the heterodimeric IL-2Rβγ receptor complex that is expressed on resting T-cells and NK cells. By avoiding binding to IL-2Rα, this molecule circumvents the preferential T-reg activation of native IL-2, while maintaining the robust stimulatory effects on T-cells and NK-cells in vitro. In vivo studies in both mice and cynomolgus monkeys confirm the molecule’s in vivo biological activity, extended pharmacodynamics due to the Fc portion of the molecule, and enhanced safety profile. Together, these results demonstrate that the bispecific antibody is a safe and effective IL-2R agonist that harnesses the benefits of the IL-2 signaling pathway as a potential anti-cancer therapy.

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Advanced Functional Materials Based on Nanocellulose for Pharmaceutical/Medical Applications

Pharmaceutics ◽

10.3390/pharmaceutics13081125 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1125

Author(s):

Raluca Nicu ◽

Florin Ciolacu ◽

Diana E. Ciolacu

Keyword(s):

Rapid Development ◽

Cellulose Nanofibrils ◽

Functional Materials ◽

Medical Applications ◽

Bacterial Nanocellulose ◽

Green Materials ◽

Wide Range ◽

In Vivo Cytotoxicity

Nanocelluloses (NCs), with their remarkable characteristics, have proven to be one of the most promising “green” materials of our times and have received special attention from researchers in nanomaterials. A diversity of new functional materials with a wide range of biomedical applications has been designed based on the most desirable properties of NCs, such as biocompatibility, biodegradability, and their special physicochemical properties. In this context and under the pressure of rapid development of this field, it is imperative to synthesize the successes and the new requirements in a comprehensive review. The first part of this work provides a brief review of the characteristics of the NCs (cellulose nanocrystals—CNC, cellulose nanofibrils—CNF, and bacterial nanocellulose—BNC), as well as of the main functional materials based on NCs (hydrogels, nanogels, and nanocomposites). The second part presents an extensive review of research over the past five years on promising pharmaceutical and medical applications of nanocellulose-based materials, which have been discussed in three important areas: drug-delivery systems, materials for wound-healing applications, as well as tissue engineering. Finally, an in-depth assessment of the in vitro and in vivo cytotoxicity of NCs-based materials, as well as the challenges related to their biodegradability, is performed.

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Anti-tumor effects of RTX-240: an engineered red blood cell expressing 4-1BB ligand and interleukin-15

Cancer Immunology Immunotherapy ◽

10.1007/s00262-021-03001-7 ◽

2021 ◽

Author(s):

Shannon L. McArdel ◽

Anne-Sophie Dugast ◽

Maegan E. Hoover ◽

Arjun Bollampalli ◽

Enping Hong ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Blood Cell ◽

Nk Cells ◽

Red Blood Cell ◽

Safety Profile ◽

Nk Cell ◽

Cell Activity ◽

In Vivo Studies

AbstractRecombinant agonists that activate co-stimulatory and cytokine receptors have shown limited clinical anticancer utility, potentially due to narrow therapeutic windows, the need for coordinated activation of co-stimulatory and cytokine pathways and the failure of agonistic antibodies to recapitulate signaling by endogenous ligands. RTX-240 is a genetically engineered red blood cell expressing 4-1BBL and IL-15/IL-15Rα fusion (IL-15TP). RTX-240 is designed to potently and simultaneously stimulate the 4-1BB and IL-15 pathways, thereby activating and expanding T cells and NK cells, while potentially offering an improved safety profile through restricted biodistribution. We assessed the ability of RTX-240 to expand and activate T cells and NK cells and evaluated the in vivo efficacy, pharmacodynamics and tolerability using murine models. Treatment of PBMCs with RTX-240 induced T cell and NK cell activation and proliferation. In vivo studies using mRBC-240, a mouse surrogate for RTX-240, revealed biodistribution predominantly to the red pulp of the spleen, leading to CD8 + T cell and NK cell expansion. mRBC-240 was efficacious in a B16-F10 melanoma model and led to increased NK cell infiltration into the lungs. mRBC-240 significantly inhibited CT26 tumor growth, in association with an increase in tumor-infiltrating proliferating and cytotoxic CD8 + T cells. mRBC-240 was tolerated and showed no evidence of hepatic injury at the highest feasible dose, compared with a 4-1BB agonistic antibody. RTX-240 promotes T cell and NK cell activity in preclinical models and shows efficacy and an improved safety profile. Based on these data, RTX-240 is now being evaluated in a clinical trial.

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Impact of β2 integrin deficiency on mouse natural killer cell development and function

Blood ◽

10.1182/blood-2010-10-315457 ◽

2011 ◽

Vol 117 (10) ◽

pp. 2874-2882 ◽

Cited By ~ 18

Author(s):

Karine Crozat ◽

Céline Eidenschenk ◽

Baptiste N. Jaeger ◽

Philippe Krebs ◽

Sophie Guia ◽

...

Keyword(s):

Cell Surface ◽

Nk Cells ◽

Natural Killer ◽

Nk Cell ◽

Surface Expression ◽

Cell Maturation ◽

Cell Surface Expression ◽

Mcmv Infection ◽

Β2 Integrin

Abstract Natural killer (NK) cells are innate immune cells that express members of the leukocyte β2 integrin family in humans and mice. These CD11/CD18 heterodimers play critical roles in leukocyte trafficking, immune synapse formation, and costimulation. The cell-surface expression of one of these integrins, CD11b/CD18, is also recognized as a major marker of mouse NK-cell maturation, but its function on NK cells has been largely ignored. Using N-ethyl-N-nitrosourea (ENU) mutagenesis, we generated a mouse carrying an A → T transverse mutation in the Itgb2 gene, resulting in a mutation that prevented the cell-surface expression of CD18 and its associated CD11a, CD11b, and CD11c proteins. We show that β2 integrin–deficient NK cells have a hyporesponsive phenotype in vitro, and present an alteration of their in vivo developmental program characterized by a selective accumulation of c-kit+ cells. NK-cell missing-self recognition was partially altered in vivo, whereas the early immune response to mouse cytomegalovirus (MCMV) infection occurred normally in CD18-deficient mice. Therefore, β2 integrins are required for optimal NK-cell maturation, but this deficiency is partial and can be bypassed during MCMV infection, highlighting the robustness of antiviral protective responses.

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150 GAIA-102: a new class off-the-shelf allogeneic NK-like cells that can eliminate solid tumors

Journal for ImmunoTherapy of Cancer ◽

10.1136/jitc-2020-sitc2020.0150 ◽

2020 ◽

Vol 8 (Suppl 3) ◽

pp. A163-A163

Author(s):

Yui Harada ◽

Yoshikazu Yonemitsu

Keyword(s):

Nk Cells ◽

Solid Tumors ◽

Tumor Cells ◽

Adoptive Immunotherapy ◽

Nk Cell ◽

Peritoneal Dissemination ◽

Checkpoint Inhibitors ◽

Antitumor Effects ◽

Car T

BackgroundCancer immunotherapy has been established as a new therapeutic category since the recent success of immune checkpoint inhibitors and a type of adoptive immunotherapy, namely chimeric antigen receptor-modified T cells (CAR-T). Although CAR-T demonstrated impressive clinical results, serious adverse effects (cytokine storm and on-target off-tumor toxicity) and undefined efficacy on solid tumors are important issues to be solved. We’ve developed a cutting-edge, simple, and feeder-free method to generate highly activated and expanded human NK cells from peripheral blood (US9404083, PCT/JP2019/012744, PCT/JP2020/012386), and have been conducting further investigation why our new type of NK cells, named as GAIA-102, are so effective to kill malignant cells.MethodsCryopreserved PBMCs purchased from vendors were mixed and processed by using LOVO and CliniMACS® Prodigy (automated/closed systems). CD3+ and CD34+ cells were depleted, and the cells were cultured with high concentration of hIL-2 and 5% UltraGRO® for 14 days in our original closed system. Then, we confirmed the expression of surface markers, CD107a mobilization and cell-mediated cytotoxicity against various tumor cells and normal cells with or without monoclonal antibody drugs in vitro and antitumor effects against peritoneal dissemination model using SKOV3 in vivo.ResultsImportantly, we’ve found that our GAIA-102 exhibited CD3-/CD56bright/CD57- immature phenotype that could kill various tumor cells efficiently from various origins, including Raji cells that was highly resistant to NK cell killing. More importantly, massive accumulation, retention, infiltration and sphere destruction by GAIA-102 were affected neither by myeloid-derived suppressor cells nor regulatory T-lymphocytes. GAIA-102 was also effective in vivo to murine model of peritoneal dissemination of human ovarian cancer; thus, these findings indicate that GAIA-102 has a potential to be an ‘upward compatible’ modality over CAR-T strategy, and would be a new and promising candidate for adoptive immunotherapy against solid tumors.ConclusionsWe now just started GMP/GCTP production of this new and powerful NK cells and first-in-human clinical trials in use of GAIA-102 will be initiated on 2021.Ethics ApprovalThe animal experiments were reviewed and approved by the Institutional Animal Care and Use Committee of Kyushu University (approval nos. A30-234-0 and A30-359-0).

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Soluble and Exosome-Bound α-Galactosylceramide Mediate Preferential Proliferation of Educated NK Cells with Increased Anti-Tumor Capacity

Cancers ◽

10.3390/cancers13020298 ◽

2021 ◽

Vol 13 (2) ◽

pp. 298

Author(s):

Arnika K. Wagner ◽

Ulf Gehrmann ◽

Stefanie Hiltbrunner ◽

Valentina Carannante ◽

Thuy T. Luu ◽

...

Keyword(s):

Nk Cells ◽

Cancer Immunotherapy ◽

Nk Cell ◽

Mouse Strains ◽

Target Cells ◽

Class I Mhc ◽

Mhc I ◽

Cell Responses ◽

Missing Self

Natural killer (NK) cells can kill target cells via the recognition of stress molecules and down-regulation of major histocompatibility complex class I (MHC-I). Some NK cells are educated to recognize and kill cells that have lost their MHC-I expression, e.g., tumor or virus-infected cells. A desired property of cancer immunotherapy is, therefore, to activate educated NK cells during anti-tumor responses in vivo. We here analyze NK cell responses to α-galactosylceramide (αGC), a potent activator of invariant NKT (iNKT) cells, or to exosomes loaded with αGC. In mouse strains which express different MHC-I alleles using an extended NK cell flow cytometry panel, we show that αGC induces a biased NK cell proliferation of educated NK cells. Importantly, iNKT cell-induced activation of NK cells selectively increased in vivo missing self-responses, leading to more effective rejection of tumor cells. Exosomes from antigen-presenting cells are attractive anti-cancer therapy tools as they may induce both innate and adaptive immune responses, thereby addressing the hurdle of tumor heterogeneity. Adding αGC to antigen-loaded dendritic-cell-derived exosomes also led to an increase in missing self-responses in addition to boosted T and B cell responses. This study manifests αGC as an attractive adjuvant in cancer immunotherapy, as it increases the functional capacity of educated NK cells and enhances the innate, missing self-based antitumor response.

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