BACKGROUND OF THE INVENTION

Cancer immunotherapy has demonstrated exciting clinical results in the setting of numerous solid tumors and hematologic malignancies. The endogenous immune system is typically non-reactive to malignant cells, or can be actively immunosuppressive with respect to the body's reaction to the presence of malignant cells. One way to enhance treatment of tumors is to force tumor recognition by the immune system through genetic engineering of leukocytes. T cells can be engineered to express a synthetic immunoreceptor comprising an extracellular targeted antibody and intracellular signaling domain, known as chimeric antigen receptor (CAR). T cells expressing a CAR directed against CD19 have been shown to have profound antileukemic efficacy, where complete remission has been achieved in 90% of acute lymphoblastic leukemia patients treated (Maude, et al., NEJM, vol. 371:1507-17, 2014). These results are accompanied by robust T cell proliferation and clearly documented T cell infiltration into tumor sites in leukemic patients so treated. Despite the high response rates demonstrated in hematopoietic malignancies, CAR T cell efficacy in solid tumors (as well as in certain lymphoid tumors) may be limited. Possible explanations for this include the potentially impaired ability of T cells to infiltrate solid tumors, poor trafficking, immunosuppressive tumor microenvironment, and expression of few tumor specific antigenson solid tumor cells.

A need exists in the art for more effective compositions and methods that treat cancers by improving specificity for tumor cells and improving infiltration into tumor sites in both solid tumors and hematologic malignancies by such compositions. The present invention fulfils this need.

SUMMARY OF THE INVENTION

As disclosed herein, the present invention includes compositions and methods of using a phagocytic cell with targeted effector activity.

In one aspect, the invention includes a modified cell comprising a chimeric antigen receptor (CAR), wherein the CAR comprises an antigen binding domain, a transmembrane domain and an intracellular domain of a stimulatory and/or co-stimulatory molecule, and wherein cell is a monocyte, macrophage, or dendritic cell that possesses targeted effector activity.

In another aspect, the invention includes a modified cell comprising a nucleic acid sequence encoding a chimeric antigen receptor (CAR), wherein nucleic acid sequence comprises a nucleic acid sequence encoding an antigen binding domain, a nucleic acid sequence encoding a transmembrane domain and a nucleic acid sequence encoding an intracellular domain of a stimulatory and/or co-stimulatory molecule, and wherein the cell is a monocyte, macrophage, or dendritic cell that expresses the CAR and possesses targeted effector activity.

In yet another aspect, the invention includes a method of modifying a cell comprising introducing a chimeric antigen receptor (CAR) into the monocyte, macrophage, or dendritic cell, wherein the CAR comprises an antigen binding domain, a transmembrane domain and an intracellular domain of a stimulatory and/or co-stimulatory molecule, and wherein the cell is a monocyte, macrophage, or dendritic cell that expresses the CAR and possesses targeted effector activity.

In still another aspect, the invention includes a composition comprising the cell modified according the method described herein.

In various embodiments of the above aspects or any other aspect of the invention delineated herein, the antigen binding domain of the CAR comprises an antibody selected from the group consisting of a monoclonal antibody, a polyclonal antibody, a synthetic antibody, human antibody, humanized antibody, single domain antibody, single chain variable fragment, and antigen-binding fragments thereof. In another embodiment, the antigen binding domain of the CAR is selected from the group consisting of an anti-CD19 antibody, an anti-HER2 antibody, and a fragment thereof. In yet another embodiment, the intracellular domain of the CAR comprises dual signaling domains.

In another embodiment, the targeted effector activity is directed against an antigen on a target cell that specifically binds the antigen binding domain of the CAR. In yet another embodiment, the targeted effector activity is selected from the group consisting of phagocytosis, targeted cellular cytotoxicity, antigen presentation, and cytokine secretion.

In another embodiment, the composition further comprises an agent selected from the group consisting of a nucleic acid, an antibiotic, an anti-inflammatory agent, an antibody or antibody fragments thereof, a growth factor, a cytokine, an enzyme, a protein, a peptide, a fusion protein, a synthetic molecule, an organic molecule, a carbohydrate or the like, a lipid, a hormone, a microsome, a derivative or a variation thereof, and any combination thereof.

In another embodiment, the modified cell has at least one upregulated M1 marker and at least one downregulated M2 marker. In yet another embodiment, the modified cell is genetically modified to express the CAR. In still another embodiment, the targeted effector activity is enhanced by inhibition of CD47 or SIRPa activity.

In another embodiment, introducing the CAR into the cell comprises introducing a nucleic acid sequence encoding the CAR, such as electroporating a mRNA encoding the CAR or transducing the cell with a viral vector comprising the nucleic acid sequence encoding the CAR.

In another embodiment, the targeted effector activity is directed against an antigen on a target cell that specifically binds the antigen binding domain of the CAR. In another embodiment, the targeted effector activity is selected from the group consisting of phagocytosis, targeted cellular cytotoxicity, antigen presentation, and cytokine secretion.

In another embodiment, the method described herein further comprises inhibiting CD47 or SIRPα activity to enhance the targeted effector activity, such as by contacting the cell with a blocking anti-CD47 or a blocking anti-SIRPα antibody. In yet another embodiment, the method further comprises modifying the cell to deliver an agent to a target, wherein the agent is selected from the group consisting of a nucleic acid, an antibiotic, an anti-inflammatory agent, an antibody or antibody fragments thereof, a growth factor, a cytokine, an enzyme, a protein, a peptide, a fusion protein, a synthetic molecule, an organic molecule, a carbohydrate or the like, a lipid, a hormone, a microsome, a derivative or a variation thereof, and any combination thereof.

In one aspect, the invention includes a pharmaceutical composition comprising the cell described herein.

In another aspect, the invention includes a use of the modified cell described herein in the manufacture of a medicament for the treatment of an immune response in a subject in need thereof. In yet another aspect, the invention includes a use of the modified cell described herein in the manufacture of a medicament for the treatment of a tumor or cancer in a subject in need thereof.

In yet another aspect, the invention includes a method of treating a disease or condition associated with a tumor or cancer in a subject comprising administering to the subject a therapeutically effective amount of a pharmaceutical composition comprising the modified cell described herein.

In still another aspect, the invention includes a method of treating a tumor in a subject, comprising administering to the subject a therapeutically effective amount of a pharmaceutical composition comprising the modified cell described herein.

In another aspect, the invention includes a method for stimulating an immune response to a target tumor cell or tumor tissue in a subject comprising administering to a subject a therapeutically effective amount of a pharmaceutical composition comprising the modified cell described herein.

