Chimeric antigen receptor dendritic cell (car-dc) for treatment of cancer

Abstract

The current invention provides monocytic cells transfected with chimeric antigen receptor (CAR) to selectively home to tumors and upon homing differentiate into dendritic cells capable of activating immunity which is inhibitory to said tumor. In one embodiment of the invention, monocytic cells are transfected with a construct encoding an antigen binding domain, a transcellular or structural domain, and an intracellular signaling domain. In one specific aspect of the invention, the antigen binding domain interacts with sufficient affinity to a tumor antigen, capable of triggering said intracellular domain to induce an activation signal to induce monocyte differentiation into DC.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application claims the benefit of U.S. Provisional Application No. 62 / 118,027 filed on Feb. 19, 2015, the contents of which are incorporated herein by reference in its entirety.FIELD OF THE INVENTION[0002]The present disclosure generally relates to the fields of genetics, immunology and medicine. The invention pertains to the field of immunotherapy, more specifically the invention pertains to the utilization of monocytes that have been manipulated to home to tumor cells and upon binding to tumor antigens differentiating into monocytes with cytotoxic properties to tumors, or dendritic cells.BACKGROUND OF THE INVENTION[0003]The immune system possesses the power to cure cancers based on published reports of immunologically mediated spontaneous regressions, which have been document in colon, lung, melanoma, liver, breast. Intriguingly, spontaneous regression clinically, as well as in an animal model of spontaneous regression, seems to be ...

AI Technical Summary

Benefits of technology

[0029]The term “enhanced function of a T cell”, “enhanced cytotoxicity” and “augmented activity” means that the effector function of the T cell and / or NK cell is improved. The enhanced function of the T cell and / or NK cell, which does not limit the present invention, includes an improvement in the proliferation rate of the T cell and / or NK cell, an increase in the production amount of cytokine, or an improvement in cytotoxity. Further, the enhanced function of the T cell and / or NK cell includes cancellation and suppression of tolerance of the T cell and / or NK cell in the suppressed state such as the anergy (unresponsive) state, or the rest state, that is, transfer of the T cell and / or NK cell from the suppressed state into the state where the T cell and / or NK cell responds to stimulation from the outside.

[0044]Irradiated tissues induce a TLR-1 reprogramming of macrophages to promote tumor growth and angiogenesis. Macrophage promotion of tumor growth is seen in numerous situations, in one example, treating of tumor bearing animals with BRAF inhibitors results in upregulation of macrophage production of VEGF which accelerates tumor growth. Mechanistically, it is known that tumors produce factors such as GM-CSF which in part stimulate macrophages to produce CCL18, which promotes tumor metastasis. Additionally, the lactic acid microenvironment of the tumor has been shown to promote skewing of macrophages towards at tumor-promoting M2 type. It has been shown that lactic acid produced by tumour cells, as a by-product of aerobic or anaerobic glycolysis, possesses an essential role in inducing the expression of VEGF and the M2-like polarization of tumour-associated macrophages, specifically inducing expression of arginase 1 through a HIF-lalpha dependent pathway. Mechanistically, it is known that lactic acid in tumors is generated in a large part by lactate dehydrogenase-A (LDH-A), which converts pyruvate to lactate. siRNA silencing of LDH-A in Pan02 pancreatic cancer cells that are injected in C57BL / 6 mice results in development of smaller tumors than mice injected with wild type, non-silenced Pan02 cells. Associated with the reduced tumor growth were observations of a decrease in the frequency of myeloid-derived suppressor cells (MDSCs) in the spleens of mice carrying LDH-A-silenced tumors. NK cells from LDH-A-depleted tumors had improved cytolytic function. Exogenous lactate administration was shown to increase the frequency of MDSCs generated from mouse bone marrow cells with GM-CSF and IL-6 in vitro. Furthermore lactate pretreatment of NK cells in vitro inhibited cytolytic function of both human and mouse NK cells. This reduction of NK cytotoxic activity was accompanied by lower expression of perforin and granzyme in NK cells. The expression of NKp46 was lower in lactate-treated NK cells. Accordingly, in one embodiment of the invention, depletion of glucose levels using a ketogenic diet to lower lactate production by glycolytic tumors is utilized to augment therapeutic effects of CAR-DC. Utilization of ketogenic diet has been previously described for immune modulation, and cancer therapy. Specific quantification of intratumoral lactate and its manipulation has been described and incorporated by reference. Potentiation of chemotherapeutic and radiotherapeutic effects by ketogenic diets have been reported and techniques are incorporated by reference for use with the current CAR-DC invention. Suppression of tumor growth and activity induced by ketogenic diet may be augmented by addition of hyperbaric oxygen, thus in one embodiment of the invention, the utilization of oxidative therapies, as disclosed in references incorporated, together with ketogenic diet is utilized to augment therapeutic efficacy of CAR-DC.

[0047]Vinblastine is a widely used chemotherapeutic agent that has been demonstrated to induce dendritic cell maturation. In one embodiment of the invention CAR-DC are utilized together with vinblastine therapy to induce augmented anticancer activity. Oxiplatin and anthracyclines have been demonstrated to not only directly kill tumor cells but also stimulate T cell immunity against tumor cells. It was demonstrated that these agents induce a rapid and prominent invasion of interleukin (IL)-17-producing γδ (Vy4(+) and Vy6(+)) T lymphocytes (γδ T17 cells) that precedes the accumulation of CD8 CTLs within the tumor bed. In T cell receptor δ(− / −) or Vy4 / 6(− / −) mice, the therapeutic efficacy of chemotherapy was reduced and furthermore no IL-17 was produced by tumor-infiltrating T cells, and CD8 CTLs did not invade the tumor after treatment. Although γδ Th17 cells could produce both IL-17A and IL-22, the absence of a functional IL-17A-IL-17R pathway significantly reduced tumor-specific T cell responses elicited by tumor cell death, and the efficacy of chemotherapy in four independent transplantable tumor models. The adoptive transfer of γδ T cells to naïve mice restored the efficacy of chemotherapy in IL-17A(− / −) hosts. The anticancer effect of infused γδ T cells was lost when they lacked either IL-1R1 or IL-17A.

Problems solved by technology

Despite the intellectual appeal of peptide based cancer vaccines, the response rate has been disappointingly low.

Despite of the promise that CAR T cells might have in treating cancer patients there are several limitations to the generalized clinical application of CAR T cells.

Second, the financial cost and labor-intensive tasks associated with identifying and engineering scFvs against a variety of tumor antigens poses a major challenge.

Third, tumor antigens targeted by CAR could be down-regulated or mutated in response to treatment resulting in tumor evasion.

Since current CAR T cells recognize only one target antigen, such changes in tumors negate the therapeutic effects.

Finally, CAR T cells react with target antigen weakly expressed on non-tumor cells, potentially causing severe adverse effects.

And although ongoing studies are focused on generating methods to shut off CAR T cells in vivo this system has yet to be developed and might pose additional inherent challenges.