scholarly journals Enhancing the antitumor functions of invariant natural killer T cells using a soluble CD1d-CD19 fusion protein

2019 ◽  
Vol 3 (5) ◽  
pp. 813-824 ◽  
Author(s):  
Rupali Das ◽  
Peng Guan ◽  
Susan J. Wiener ◽  
Nishant P. Patel ◽  
Trevor G. Gohl ◽  
...  
Keyword(s):  
Fusion Protein ◽  
B Cell ◽  
Natural Killer ◽  
Tumor Cells ◽  
Inkt Cell ◽  
Inkt Cells ◽  
Cell Responses ◽  
Invariant Natural Killer

Abstract Invariant natural killer T (iNKT) cells comprise a unique lineage of CD1d-restricted lipid-reactive T lymphocytes that potently kill tumor cells and exhibit robust immunostimulatory functions. Optimal tumor-directed iNKT cell responses often require expression of the antigen-presenting molecule CD1d on tumors; however, many tumor cells downregulate CD1d and thus evade iNKT cell recognition. We generated a soluble bispecific fusion protein designed to direct iNKT cells to the site of B-cell cancers in a tumor antigen-specific but CD1d-independent manner. This fusion protein is composed of a human CD1d molecule joined to a single chain antibody FV fragment specific for CD19, an antigen widely expressed on B-cell cancers. The CD1d-CD19 fusion protein binds specifically to CD19-expressing, but not CD19-negative cells. Once loaded with the iNKT cell lipid agonist α-galactosyl ceramide (αGC), the CD1d-CD19 fusion induces robust in vitro activation of and cytokine production by human iNKT cells. iNKT cells stimulated by the αGC-loaded CD1d-CD19 fusion also strongly transactivate T-, B-, and NK-cell responses and promote dendritic cell maturation. Importantly, the αGC-loaded fusion induces robust lysis of CD19+CD1d− Epstein-Barr virus immortalized human B-lymphoblastoid cell lines that are otherwise resistant to iNKT cell killing. Consistent with these findings; administration of the αGC-loaded fusion protein controlled the growth of CD19+CD1d− tumors in vivo, suggesting that it can “link” iNKT cells and CD19+CD1d− targets in a therapeutically beneficial manner. Taken together, these preclinical studies demonstrate that this B cell–directed fusion protein can be used to effectively induce iNKT cell antitumor responses in vitro and in vivo.

Abstract 541: Specific Deletion of LDL Receptor--Related Protein on Macrophages Skews Cytokine Production by Invariant Natural Killer T Cells

2014 ◽  
Vol 34 (suppl_1) ◽  
Author(s):  
Roman Covarrubias ◽  
Amy S Major
Keyword(s):  
Natural Killer ◽  
Cell Activation ◽  
Ldl Receptor ◽  
Inkt Cell ◽  
Related Protein ◽  
Inkt Cells ◽  
Glycolipid Antigen ◽  
Invariant Natural Killer ◽  
Natural Killer T

Invariant Natural Killer T (iNKT) cells are specialized lymphocytes that when activated can regulate chronic inflammatory conditions and atherosclerotic processes. The activation of iNKT cells occurs when glycolipid antigens bind the MHC class-I like molecule CD1d present on antigen presenting cells (APCs). The pathways by which glycolipid antigens target CD1d for presentation and activation of iNKT cells remain unclear, yet the expression of surface receptors associated with lipid homeostasis, such as the LDL receptor (LDLr), have been implicated in the modulation of iNKT cell activation. The LDLr has been shown to modulate this process by binding apoE-containing lipoproteins, which can carry antigenic glycolipids for iNKT cell activation. The LDL receptor-related protein (LRP), a transmembrane receptor from the LDL receptor family of proteins, shares structural homology with LDLr and can bind a number of ligands including apoE-containing lipoproteins. We hypothesized that LRP can play an active role in glycolipid antigen presentation and subsequent activation of iNKT cells. Here, we demonstrate that LRP is preferentially expressed at high levels on F4/80 + macrophages, when compared to other APCs. We also show that a specialized subset of macrophages expressing CD169, known for their ability to present glycolipid antigen to iNKT cells, have increased levels of LRP when compared to CD169 - macrophages. Using mice with a targeted deletion of LRP in macrophages, we observed decreased activation of iNKT cells in vitro (24, 48 hours) and normal IFN-gamma but blunted IL-4 response in vivo. Further flow cytometric analysis showed normal surface expression of CD1d in LRP-cKO macrophages as well as normal uptake of fluorescently labeled glycolipid in vitro . Additionally, analysis of the iNKT cell compartment in LRP-cKO mice revealed intact numbers and percentages of iNKT cells and no homeostatic disruption as evidenced by absence of programmed death-1 and LY-49. Collectively, these data suggest that macrophage LRP contributes to early iNKT cell activation by enhancing early IL-4 responses.

scholarly journals Invariant Natural Killer T Cell Subsets Have Diverse Graft-Versus-Host-Disease-Preventing and Anti-Tumor Effects

Blood ◽  
2021 ◽  
Author(s):  
Kristina Maas-Bauer ◽  
Juliane K. Lohmeyer ◽  
Toshihito Hirai ◽  
Teresa Lopes Ramos ◽  
Furqan Muhammad Fazal ◽  
...  
Keyword(s):  
T Cell ◽  
Antitumor Activity ◽  
Natural Killer ◽  
Graft Versus Host Disease ◽  
Inkt Cells ◽  
Host Disease ◽  
Graft Versus Host ◽  
Invariant Natural Killer

Invariant Natural Killer T (iNKT) cells are a T cell subset with potent immunomodulatory properties. Experimental evidence in mice and observational studies in humans indicate that iNKT cells have antitumor potential as well as the ability to suppress acute and chronic Graft-versus-Host-Disease (GvHD). Murine iNKT cells differentiate during thymic development into iNKT1, iNKT2 and iNKT17 sublineages, which differ transcriptomically and epigenomically, and have subset-specific developmental requirements. Whether distinct iNKT sublineages also differ in their antitumor effect and their ability to suppress GvHD is currently unknown. In this work, we generated highly purified murine iNKT-sublineages, characterized their transcriptomic and epigenomic landscape, and assessed specific functions. We demonstrate that iNKT2 and iNKT17, but not iNKT1 cells, efficiently suppress T cell activation in vitro and mitigate murine acute GvHD in vivo. Conversely, we show that iNKT1 cells display the highest antitumor activity against murine B-cell lymphoma cells both in vitro and in vivo. Thus, we demonstrate for the first time that iNKT sublineages have distinct and different functions, with iNKT1 cells having the highest antitumor activity and iNKT2 and iNKT17 cells having immune-regulatory properties. These results have important implications for the translation of iNKT cell therapies to the clinic for cancer immunotherapy as well as for GvHD prevention and treatment.

scholarly journals Combination of NKT14m and Low Dose IL-12 Promotes Invariant Natural Killer T Cell IFN-γ Production and Tumor Control

2020 ◽  
Vol 21 (14) ◽  
pp. 5085
Author(s):  
Peng Guan ◽  
Robert Schaub ◽  
Kim E. Nichols ◽  
Rupali Das
Keyword(s):  
T Cell ◽  
Natural Killer ◽  
Low Dose ◽  
Inkt Cell ◽  
Tumor Control ◽  
Inkt Cells ◽  
Ifn Γ ◽  
Invariant Natural Killer ◽  
Natural Killer T

Invariant natural killer T (iNKT) cells are innate-like T lymphocytes characterized by the expression of an invariant T cell receptor (iTCR) that recognizes glycolipid antigens presented by the MHC I-like CD1d molecule. Following antigenic stimulation, iNKT cells rapidly produce large amounts of cytokines that can trans-activate dendritic cells (DC) and promote the anti-tumor functions of cytotoxic lymphocytes, such as natural killer (NK) and CD8 T cells. Additionally, iNKT cells can mediate robust and direct cytotoxicity against CD1d+ tumor targets. However, many tumors down-regulate CD1d and evade iNKT cell attack. To circumvent this critical barrier to iNKT cell anti-tumor activity, a novel monoclonal antibody (mAb), NKT14 has been recently developed. This agonistic antibody binds directly and specifically to the iTCR of murine iNKT cells. In the current study, we demonstrate that NKT14m mediates robust activation, cytokine production and degranulation of murine iNKT cells, in vitro. Consistently, NKT14m also promoted iNKT cell activation and immunomodulatory functions, in vivo. Finally, administration of NKT14m with low dose interleukin (IL)-12 further augmented iNKT cell IFN-γ production in vivo, and this combination conferred superior suppression of tumor cell growth compared to NKT14m or IL-12 alone. Together, these data demonstrate that a combination treatment consisting of low dose IL-12 and iTCR-specific mAb may be an attractive alternative to activate iNKT cell anti-tumor functions.

scholarly journals Mitochondrial metabolism is essential for invariant natural killer T cell development and function

2021 ◽  
Vol 118 (13) ◽  
pp. e2021385118
Author(s):  
Xiufang Weng ◽  
Amrendra Kumar ◽  
Liang Cao ◽  
Ying He ◽  
Eva Morgun ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Natural Killer ◽  
Cell Development ◽  
Mitochondrial Metabolism ◽  
Inkt Cell ◽  
Inkt Cells ◽  
And Function ◽  
Invariant Natural Killer

Conventional T cell fate and function are determined by coordination between cellular signaling and mitochondrial metabolism. Invariant natural killer T (iNKT) cells are an important subset of “innate-like” T cells that exist in a preactivated effector state, and their dependence on mitochondrial metabolism has not been previously defined genetically or in vivo. Here, we show that mature iNKT cells have reduced mitochondrial respiratory reserve and iNKT cell development was highly sensitive to perturbation of mitochondrial function. Mice with T cell-specific ablation of Rieske iron-sulfur protein (RISP; T-Uqcrfs1−/−), an essential subunit of mitochondrial complex III, had a dramatic reduction of iNKT cells in the thymus and periphery, but no significant perturbation on the development of conventional T cells. The impaired development observed in T-Uqcrfs1−/− mice stems from a cell-autonomous defect in iNKT cells, resulting in a differentiation block at the early stages of iNKT cell development. Residual iNKT cells in T-Uqcrfs1−/− mice displayed increased apoptosis but retained the ability to proliferate in vivo, suggesting that their bioenergetic and biosynthetic demands were not compromised. However, they exhibited reduced expression of activation markers, decreased T cell receptor (TCR) signaling and impaired responses to TCR and interleukin-15 stimulation. Furthermore, knocking down RISP in mature iNKT cells diminished their cytokine production, correlating with reduced NFATc2 activity. Collectively, our data provide evidence for a critical role of mitochondrial metabolism in iNKT cell development and activation outside of its traditional role in supporting cellular bioenergetic demands.

scholarly journals Genetic engineering of hematopoietic stem cells to generate invariant natural killer T cells

2015 ◽  
Vol 112 (5) ◽  
pp. 1523-1528 ◽  
Author(s):  
Drake J. Smith ◽  
Siyuan Liu ◽  
Sunjong Ji ◽  
Bo Li ◽  
Jami McLaughlin ◽  
...  
Keyword(s):  
Stem Cells ◽  
Hematopoietic Stem Cells ◽  
Natural Killer ◽  
Inkt Cell ◽  
Cell Phenotype ◽  
Inkt Cells ◽  
Hematopoietic Stem ◽  
Invariant Natural Killer ◽  
Natural Killer T

Invariant natural killer T (iNKT) cells comprise a small population of αβ T lymphocytes. They bridge the innate and adaptive immune systems and mediate strong and rapid responses to many diseases, including cancer, infections, allergies, and autoimmunity. However, the study of iNKT cell biology and the therapeutic applications of these cells are greatly limited by their small numbers in vivo (∼0.01–1% in mouse and human blood). Here, we report a new method to generate large numbers of iNKT cells in mice through T-cell receptor (TCR) gene engineering of hematopoietic stem cells (HSCs). We showed that iNKT TCR-engineered HSCs could generate a clonal population of iNKT cells. These HSC-engineered iNKT cells displayed the typical iNKT cell phenotype and functionality. They followed a two-stage developmental path, first in thymus and then in the periphery, resembling that of endogenous iNKT cells. When tested in a mouse melanoma lung metastasis model, the HSC-engineered iNKT cells effectively protected mice from tumor metastasis. This method provides a powerful and high-throughput tool to investigate the in vivo development and functionality of clonal iNKT cells in mice. More importantly, this method takes advantage of the self-renewal and longevity of HSCs to generate a long-term supply of engineered iNKT cells, thus opening up a new avenue for iNKT cell-based immunotherapy.

scholarly journals 3502 Stimulating iNKT Cell-Mediated Neuroblastoma Cytotoxicity in a Mouse Model

2019 ◽  
Vol 3 (s1) ◽  
pp. 21-21
Author(s):  
Kevin Owen McNerney ◽  
Hamid Bassiri ◽  
Spyridon Karageorgos ◽  
Priya Khurana
Keyword(s):  
Tumor Microenvironment ◽  
Mouse Model ◽  
Neuroblastoma Cells ◽  
Prolonged Survival ◽  
Inkt Cell ◽  
Inkt Cells ◽  
Glycolipid Antigen ◽  
High Affinity

OBJECTIVES/SPECIFIC AIMS: Overall Research Aim: To develop an iNKT-cell engaging reagent (“CAb”)to induce neuroblastoma-directed cytotoxicity in vitro and in a mouse model of neuroblastoma. Objective 1: Explore the contribution of different GD2 affinities to the cytotoxicity against neuroblastoma cells in vitro. Objective 2: Deteremine whether use of different stimulatory glycolipids (alpha-GalCer vs. C34) alter the activation and cytotoxicity of iNKT cells against neuroblastoma in vitro. Objective 3: To analyze survival of an immunocompetent mouse model of neuroblastoma treated with C34-loaded vs alpha-GalCer-loaded CAb molecule, and to analyze the tumor microenvironment in each treatment condition. METHODS/STUDY POPULATION: CAb molecule will be generated by fusing a CD1d protein to an scFv domain for GD2 using cloning techniques. Previous work by our group has used a streptavidin-biotin system to link CD1d to an antibody against GD2, which is large and immunogenic. Protein expression of this novel fusion protein will occur in HEK293 cells. This new CAb molecule will then be loaded with alpha-GalCer or C34 for use in cytotoxicity and in vivo experiments. Cytotoxicity Assessment: Chromium assays will be used to assess the specific cytotoxicity generated by iNKT cells against neuroblastoma cells in vitro. iNKT cells will be activated by “CAb’s” with relatively high and low affinity for GD2, and also with Alpha-GalCer and C34 glycolipid antigen. flow cytometry will be used to assess for CD107a and Interferon Gamma. Mouse Model of Neuroblastoma: TH-MYCN +/+ mice will be used as an immunocompetent model of neuroblastoma. These mice have the MYCN gene under the control of a tyrosine hydroxylase promoter, and spontaneously develop neuroblastomas by 2 weeks of life which are uniformly fatal by 8 weeks of life. In vivo survival studies will be conducted by injecting CAb of relatively high and low affinity, loaded with glycolipid antigen intraperitonealy into TH-MYCN+/+ mice starting at 2 weeks of age, twice weekly. There will also be a matched negative control. Treatment groups are listed below: 1. alpha-GalCer loaded high-affinity Cab 2. alpha-GalCer loaded low-affinity Cab 3. C34-loaded high-affinity Cab 4. C34-loaded low-affinity Cab 5. Unloaded high-affinity Cab 6. Unloaded low-affinity Cab Enrollment will be 6 mice per group for the survival curves. Tumor Microenvironment analysis: 2 additional mice will be included in each group listed above to be sacrificed 2 weeks into treatment for tumor assessment with flow cytomtetry for iNKT cell, NK cell, T-Lymphocyte frequencies as well as interferon-Gamma expression. RESULTS/ANTICIPATED RESULTS: Objective 1: We expect to find that the highest affinity scFv domains for GD2 result in the greatest amount of cytotoxicity against neuroblastoma cells via iNKT cells. Objective 2: We expect that the C34 molecule will induce the greatest amounts of iNKT cell activation against neuroblastoma cells and higher cytotoxicity against neuroblastoma, which has not been shown previously. Objective 3: We expect to see prolonged survival of mice treated with the high affinity GD2 CAb loaded with C34 or alpha GalCer compared with the low affinity CAb loaded with C34 or alpha GalCer. We also expect that the C34 loaded CAb in both groups will have prolonged survival when compared with the alpha-GalCer loaded CAbs of either affinity. DISCUSSION/SIGNIFICANCE OF IMPACT: iNKT cells have been shown previously to confer an improved prognosis in neuroblastoma and other malignancies. Furthermore, high risk neuroblastomas tend to downregulate expression of a chemokine that attracts iNKT’s to the site of the neuroblastoma. Directing iNKT to the site of neuroblastoma holds promise as an effective immunotherapy option. Our preliminary data demonstrate that CAbs directed against GD2 are capable of exerting cytotoxicity of neuroblastoma in vitro. Furthermore a trend towards prolonged survival has been shown in TH-MYCN mice in early experiments. The development of a novel antibody that has reduced immunogenicity, incorporates a glycolipid antigen that does not induce iNKT cell anergy, and is specific for the GD2 tumor specific antigen has potential to result in increased iNKT-mediate neuroblastoma cytotoxicity and prolonged survival in TH-MYCN+/+ mice.

IL-17–producing invariant NKT cells in lymphoid organs are recent thymic emigrants identified by neuropilin-1 expression

Blood ◽  
2011 ◽  
Vol 118 (11) ◽  
pp. 2993-3002 ◽  
Author(s):  
Pierre Milpied ◽  
Bérangère Massot ◽  
Amédée Renand ◽  
Séverine Diem ◽  
André Herbelin ◽  
...  
Keyword(s):  
Cell Subset ◽  
Treg Cells ◽  
Lymphoid Organs ◽  
Inkt Cell ◽  
Inkt Cells ◽  
Invariant Nkt Cells ◽  
Neuropilin 1 ◽  
Bona Fide

Abstract Despite increasing knowledge on the mechanisms of invariant natural killer T (iNKT)–cell development in the thymus, the function of recent thymic emigrant (RTE) iNKT cells remains largely unexplored, principally because of a lack of bona fide markers to distinguish RTE from long-lived iNKT cells. Whether the recently described IL-17–producing iNKT cell subset is part of RTE has notably not been addressed. In the present study, we show that neuropilin-1 (Nrp-1), a transmembrane receptor mainly found on T-regulatory (Treg) cells in the murine immune system, is specifically expressed on RTE iNKT cells in naive mice. We used the Nrp-1 marker to discriminate RTE from mature iNKT cells and compare their functions. We show that RTE iNKT cells proliferate more than mature iNKT cells after in vitro activation; that, unlike mature iNKT cells, most RTE iNKT cells fail to rapidly produce IFN-γ and IL-4 after in vivo activation; and, most importantly, that IL-17–producing iNKT cells in lymphoid organs of naive mice are contained within the RTE iNKT cell pool. Our results establish an accurate marker of RTE iNKT cells and reveal that continuous thymic output is required for pro-inflammatory IL-17 secretion, a key function of adult iNKT cells.

scholarly journals Invariant natural killer T cells direct B cell responses to cognate lipid antigen in an IL-21-dependent manner

2011 ◽  
Vol 13 (1) ◽  
pp. 44-50 ◽  
Author(s):  
Irah L King ◽  
Anne Fortier ◽  
Michael Tighe ◽  
John Dibble ◽  
Gerald F M Watts ◽  
...  
Keyword(s):  
T Cells ◽  
B Cell ◽  
Natural Killer ◽  
Natural Killer T Cells ◽  
Dependent Manner ◽  
Cell Responses ◽  
Lipid Antigen ◽  
Killer T Cells ◽  
Invariant Natural Killer ◽  
Natural Killer T

scholarly journals Cd5 Maintains Tolerance in Anergic B Cells

2000 ◽  
Vol 191 (5) ◽  
pp. 883-890 ◽  
Author(s):  
Keli L. Hippen ◽  
Lina E. Tze ◽  
Timothy W. Behrens
Keyword(s):  
B Cells ◽  
B Cell ◽  
Cell Receptor ◽  
Immunoglobulin M ◽  
B Cell Tolerance ◽  
Cell Responses ◽  
B Cell Anergy ◽  
Clonal Anergy

Clonal anergy of autoreactive B cells is a key mechanism regulating tolerance. Here, we show that anergic B cells express significant surface levels of CD5, a molecule normally found on T cells and a subset of B-1 cells. Breeding of the hen egg lysozyme (HEL) transgenic model for B cell anergy onto the CD5 null background resulted in a spontaneous loss of B cell tolerance in vivo. Evidence for this included elevated levels of anti-HEL immunoglobulin M (IgM) antibodies in the serum of CD5−/− mice transgenic for both an HEL-specific B cell receptor (BCR) and soluble lysozyme. “Anergic” B cells lacking CD5 also showed enhanced proliferative responses in vitro and elevated intracellular Ca2+ levels at rest and after IgM cross-linking. These data support the hypothesis that CD5 negatively regulates Ig receptor signaling in anergic B cells and functions to inhibit autoimmune B cell responses.

Sign in / Sign up

Export Citation Format

Share Document