A Humanized Monoclonal Antibody Specific for Invariant Natural Killer T (iNKT) Cells for In Vivo Depletion

Invariant natural killer T cells (iNKTs) directly kill tumor cells and trans-activate the anti-tumor functions of dendritic cells (DC), natural killer (NK) cells, and T and B cells. As such, iNKTs serve as a powerful tool for use in cell-based cancer immunotherapy. iNKT cell activation commonly requires engagement of the invariant T cell receptor (iTCR) by CD1d presenting glycolipid antigens. However, transformed cells often down-regulate CD1d expression, which results in a reduction of iNKT cell anti-tumor functions. One approach to circumvent this critical barrier to iNKT cell activation is to develop an agonistic antibody that binds directly to the iTCR without the requirement for CD1d-mediated antigen presentation. To this end, we have characterized the iNKT cell stimulatory properties of NKTT320, a novel, recombinant, humanized, monoclonal antibody that binds selectively and with high affinity to human iTCRs. Strikingly, immobilized NKTT320 mediated robust iNKT cell activation (upregulation of CD25 and CD69) and proliferation (carboxyfluorescein succinimidyl ester (CFSE) dilution), as well as Th1 and Th2 cytokine production. Additionally, iNKTs stimulated by plate-bound NKTT320 exhibited increased intracellular levels of granzyme B and degranulation (exposure of CD107 on the cell surface). Furthermore, both soluble and immobilized NKTT320 induced iNKT cell-mediated activation of bystander immune cells, suggesting that this novel anti-iTCR antibody facilitates both direct and indirect iNKT cell cytotoxicity. These studies are significant, as they provide a framework by which iNKT cell anti-cancer functions could be enhanced for therapeutic purposes.

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Myeloid-Derived Suppressor Cells (MDSCs) Induced In Vivo Following Activation of Invariant Natural Killer T (iNKT) Cells Prolong the Survival of Skin Allografts

Transplantation Journal ◽

10.1097/00007890-201211271-00475 ◽

2012 ◽

Vol 94 (10S) ◽

pp. 257

Author(s):

R. Chadha ◽

K. J. Wood ◽

N. D. Jones

Keyword(s):

Natural Killer ◽

Suppressor Cells ◽

Myeloid Derived Suppressor Cells ◽

Inkt Cells ◽

Skin Allografts ◽

Invariant Natural Killer ◽

Natural Killer T

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Relevance of sexual dimorphism to regulatory T cells: estradiol promotes IFN-γ production by invariant natural killer T cells

Blood ◽

10.1182/blood-2004-07-2819 ◽

2005 ◽

Vol 105 (6) ◽

pp. 2415-2420 ◽

Cited By ~ 98

Author(s):

Pierre Gourdy ◽

Luiza M. Araujo ◽

Ren Zhu ◽

Barbara Garmy-Susini ◽

Séverine Diem ◽

...

Keyword(s):

T Cells ◽

Natural Killer ◽

Interleukin 4 ◽

Response To Treatment ◽

Inkt Cells ◽

Gender Dimorphism ◽

Ifn Γ ◽

Invariant Natural Killer ◽

Natural Killer T

Abstract Mechanisms accounting for gender dimorphism during immune responses are still poorly understood. Since invariant natural killer T (iNKT) cells exert important regulatory functions through their capacity to produce both T helper 1 (Th1) and Th2 cytokines, we addressed the question of whether these activities could be modulated by sexual hormones. We found that in vivo challenge with the specific ligand of iNKT cells, α-galactosylceramide (α-GalCer), induced significantly higher concentrations of interferon γ (IFN-γ) in the serum of female than in that of male mice, while interleukin 4 (IL-4) production was not modified. In support of a crucial role of ovarian hormones in this phenomenon, a significant decrease of serum IFN-γ concentrations occurred in ovariectomized females, in response to treatment with α-GalCer, while orchidectomy affected neither IFN-γ nor IL-4 serum concentrations in males. The implication of estrogens in this selective enhancement of IFN-γ production by iNKT cells was demonstrated by (1) the increased α-GalCer–induced IFN-γ synthesis by iNKT cells upon both in vitro and in vivo exposure to estradiol and (2) the abolition of the sex-linked difference in α-GalCer–induced IFN-γ release in estrogen receptor α-deficient mice. These results provide the first evidence that estrogens influence iNKT cells leading to this gender dimorphism in their cytokine production profile.

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

International Journal of Molecular Sciences ◽

10.3390/ijms21145085 ◽

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.

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

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1424877112 ◽

2015 ◽

Vol 112 (5) ◽

pp. 1523-1528 ◽

Cited By ~ 11

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.

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Abstract 11982: Circulating Invariant Natural Killer T Cells are Decreased in Patients With Chronic Heart Failure

Circulation ◽

10.1161/circ.130.suppl_2.11982 ◽

2014 ◽

Vol 130 (suppl_2) ◽

Author(s):

Akimichi Saito ◽

Naoki Ishimori ◽

Mikito Nishikawa ◽

Shintaro Kinugawa ◽

Hiroyuki Tsutsui

Keyword(s):

Heart Failure ◽

Chronic Heart Failure ◽

Ejection Fraction ◽

Natural Killer ◽

Left Ventricular ◽

Idiopathic Dilated Cardiomyopathy ◽

Inkt Cells ◽

Lv Ejection Fraction ◽

Invariant Natural Killer ◽

Natural Killer T

Objective: Inflammatory mediators play a crucial role in the development of chronic heart failure (HF). Invariant natural killer T (iNKT) cells, a unique subset of T lymphocytes, which recognize glycolipid antigens and secrete a large amount of T helper (Th) 1/Th2 cytokines on activation, function as immunomodulatory cells in the various pathological processes. We have demonstrated that iNKT cells have a protective role against the development of left ventricular (LV) remodeling and failure after myocardial infarction in mice. However, it remains unclear whether iNKT cells are involved in the development of HF in humans. Methods and Results: Nine HF patients (NYHA II or III, LV ejection fraction 26.3±3.0%) and 8 healthy controls were studied. The mean age and male gender were comparable between HF and controls (51.2±5.1 vs. 45.1±4.5 years and 77.8 vs. 75.0%). The causes of HF were idiopathic dilated cardiomyopathy in 3, ischemic in 2, and others in 4 patients. Plasma BNP was significantly higher in HF than in controls (739.4±207.2 vs. 19.8±6.5 pg/mL, P <0.01). The number of circulating iNKT cells, identified by the positive-staining of Vα24-Jα18 T Cell Receptor by flow-cytometric analysis, was significantly lower in HF (747±85 vs. 1058±271 counts/mL, P <0.01). Its ratio to the total lymphocyte was also significantly lower (0.111±0.004 vs. 0.146±0.035%, P <0.01). Plasma interleukin-6 and high-sensitivity CRP were significantly higher in HF (3.99±0.86 vs. 0.78±0.14 pg/mL and 0.28±0.10 vs. 0.06±0.02 mg/dL, respectively, both P <0.01). LV ejection fraction ( r =0.72, P <0.05) and plasma log BNP ( r =-0.70, P <0.05) were significantly correlated to the ratio of iNKT cells among HF patients. Conclusions: Circulating iNKT cells were decreased in HF patients, suggesting that they have a potential role in the development of human HF.

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Galacto-Configured Aminocyclitol Phytoceramides Are Potent in Vivo Invariant Natural Killer T Cell Stimulators

Journal of the American Chemical Society ◽

10.1021/ja202610x ◽

2011 ◽

Vol 133 (31) ◽

pp. 12079-12084 ◽

Cited By ~ 32

Author(s):

Youssef Harrak ◽

Carolina M. Barra ◽

Antonio Delgado ◽

A. Raúl Castaño ◽

Amadeu Llebaria

Keyword(s):

T Cell ◽

Natural Killer ◽

Natural Killer T Cell ◽

Invariant Natural Killer ◽

Killer T Cell ◽

Natural Killer T

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Evaluating The Frequency Of Invariant Natural Killer T (iNKT) Cells In Nasal Polyps

Journal of Allergy and Clinical Immunology ◽

10.1016/j.jaci.2007.12.1044 ◽

2008 ◽

Vol 121 (2) ◽

pp. S263-S263

Author(s):

M FEREIDOUNI ◽

R FARIDHOSSEINI ◽

M MAHMOUDI ◽

M BAKHSHAEI ◽

L ALHARTHI

Keyword(s):

Natural Killer ◽

Nasal Polyps ◽

Inkt Cells ◽

Invariant Natural Killer ◽

Natural Killer T

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Invariant natural killer T cells are functionally impaired in patients with systemic sclerosis

Arthritis Research & Therapy ◽

10.1186/s13075-019-1991-y ◽

2019 ◽

Vol 21 (1) ◽

Cited By ~ 1

Author(s):

Ann-Christin Pecher ◽

Felix Kettemann ◽

Elisa Asteriti ◽

Hannes Schmid ◽

Silke Duerr-Stoerzer ◽

...

Keyword(s):

Systemic Sclerosis ◽

Natural Killer ◽

Immunosuppressive Drugs ◽

Healthy Controls ◽

Inkt Cells ◽

Novel Approach ◽

Functionally Impaired ◽

Transfer Strategies ◽

Invariant Natural Killer ◽

Natural Killer T

Abstract Background Systemic sclerosis (SSc) is a potentially fatal autoimmune disease that leads to extensive fibrosis of the skin and internal organs. Invariant natural killer T (iNKT) cells are potent immunoregulatory T lymphocytes being able to orchestrate dysregulated immune responses. The purpose of this study was to evaluate numbers and function of iNKT cells in patients with SSc and to analyze their correlation with disease parameters. Methods Human iNKT cells from 88 patients with SSc and 33 healthy controls were analyzed by flow cytometry. Their proliferative capacity and cytokine production were investigated following activation with CD1d ligand α-galactosylceramide (α-GalCer). Results We observed an absolute and relative decrease of iNKT cells in patients with SSc compared with healthy controls. Interestingly, the subtype of SSc, disease severity, or treatment with immunosuppressive drugs did not affect iNKT cell numbers. However, T helper (Th) cell immune polarization was biased towards a Th17 immunophenotype in SSc patients. Moreover, iNKT cells from patients with SSc showed a significantly decreased expansion capacity upon stimulation with α-GalCer. Conclusion iNKT cells are deficient and functionally impaired in patients with SSc. Therefore, adoptive transfer strategies using culture-expanded iNKT cells could be a novel approach to treat SSc patients.

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Vitamin D, invariant natural killer T-cells and experimental autoimmune disease

Proceedings of The Nutrition Society ◽

10.1017/s0029665111003193 ◽

2011 ◽

Vol 71 (1) ◽

pp. 62-66 ◽

Cited By ~ 31

Author(s):

Margherita T. Cantorna ◽

Jun Zhao ◽

Linlin Yang

Keyword(s):

Multiple Sclerosis ◽

Vitamin D ◽

Immune System ◽

Vitamin D Deficiency ◽

Natural Killer ◽

Active Form ◽

Inkt Cells ◽

Invariant Natural Killer ◽

Experimental Autoimmune ◽

Natural Killer T

Vitamin D is an important regulator of the immune system in general and multiple sclerosis in particular. Experimentally (i), invariant natural killer T (iNKT) cells have been shown to be important suppressors of autoimmune diseases such as experimental autoimmune encephalomyelitis (EAE; an animal model of multiple sclerosis). Conversely, in experimental allergic asthma iNKT cells are required for disease induction and are therefore pathogenic. The active form of vitamin D (calcitriol) suppresses EAE. The development of EAE symptoms is accelerated in vitamin D deficiency. Interestingly experimental asthma is less severe in vitamin D deficiency although there is no effect of calcitriol on disease severity. The data suggest that an important target of vitamin D in EAE and asthma are the iNKT cells. Vitamin D and/or vitamin D receptor deficiency results in the impaired development of iNKT cells. Vitamin D is critical very early during development of the immune system. Low levels of vitamin D in utero resulted in significantly reduced numbers of iNKT cells that failed to recover when calcitriol was used to supplement neonatal or adult mice. The data suggest that one of the consequences of early vitamin D deficiency is a reduction in the numbers of iNKT cells that develop. The iNKT cells are required for the beneficial effects of calcitriol in EAE. The important role of vitamin D on iNKT cells could impact the development of human immune-mediated diseases including multiple sclerosis and asthma.

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