MODIFIED CCR POLYPEPTIDES AND USES THEREOF

1 - 130 . (canceled)

131 . A fusion polypeptide comprising:

a) a chimeric antigen receptor (CAR) comprising a first hinge region;

b) a polypeptide cleavage signal; and

c) a chimeric co-stimulatory receptor (CCR) comprising a second hinge region comprising one or more cysteines substituted with another amino acid.

132 . The fusion polypeptide of claim 131 , wherein the one or more cysteine substitutions within the second hinge region (i) reduces CCR antigen-mediated stimulation of T cell signaling in the absence of CAR antigen, compared to a CCR comprising a second hinge region without cysteine substitutions and/or (ii) reduces CAR/CCR association in the absence of CAR antigen, compared to a CCR comprising a second hinge region without cysteine substitutions.

133 . The fusion polypeptide of claim 131 , wherein the first hinge region comprises one or more cysteines substituted with a different amino acid and wherein the first hinge region (i) reduces CCR antigen-mediated stimulation of T cell signaling in the absence of CAR antigen compared to a CAR comprising a first hinge region without cysteine substitutions and/or (ii) reduces CAR/CCR association in the absence of CAR antigen compared to a CAR comprising a first hinge region without cysteine substitutions.

134 . The fusion polypeptide of claim 131 , wherein the first and second hinge regions are CD8α hinge regions or a functional fragment thereof.

135 . The fusion polypeptide of claim 131 , wherein the first or second CD8α hinge region comprises an amino acid substitution at position 27 of SEQ ID NO: 2.

136 . The fusion polypeptide of claim 131 , wherein the first or second CD8α hinge region comprises an amino acid substitution at position 44 of SEQ ID NO: 2.

137 . The fusion polypeptide of claim 131 , wherein the second CD8α hinge region comprises amino acid substitutions at positions 27 and 44 of SEQ ID NO: 2.

138 . The fusion polypeptide of claim 131 , wherein the first CD8α hinge region comprises an amino acid substitution at position 27 of SEQ ID NO: 2, and the second CD8α hinge region comprises an amino acid substitution at position 44 of SEQ ID NO: 2.

139 . The fusion polypeptide of claim 131 , wherein the first or second hinge region comprises an amino acid sequence set forth in SEQ ID NO: 3.

140 . The fusion polypeptide of claim 131 , wherein the second hinge region comprises an amino acid sequence as set forth in SEQ ID NO: 4.

141 . The fusion polypeptide of claim 131 , wherein the second hinge region comprises an amino acid sequence as set forth in SEQ ID NO: 5.

142 . A polynucleotide encoding the fusion polypeptide of claim 131 .

143 . A vector comprising the polynucleotide of claim 142 .

144 . The vector of claim 143 , wherein the vector is a lentiviral vector.

145 . A cell that expresses (i) the fusion polypeptide or (ii) the CAR and CCR of claim 131 .

146 . The cell of claim 145 , wherein the cell is (i) an immune effector cell, (ii) a T-cell, (iii) a CD3+, CD4+, and/or CD8+ cell, (iv) a cytotoxic T lymphocytes (CTLs), a tumor infiltrating lymphocytes (TILs), or a helper T cell, (v) a natural killer (NK) or natural killer T (NKT) cell, or (vi) a macrophage.

147 . A composition comprising the cell of claim 145 .

148 . A method of treating a cancer in a subject in need thereof, comprising administering to the subject a therapeutically effective amount of the composition of claim 147 .

149 . A method of reducing CCR antigen-mediated stimulation of T cell signaling in the absence of CAR antigen, compared to a CCR comprising a hinge domain without substitutions, the method comprising:

a) obtaining CAR and CCR polypeptides each having a hinge domain;

b) substituting one or more cysteine residues within the CCR hinge domain for another residue, thereby producing a modified CCR; and

c) expressing the CAR and modified CCR in a cell.

150 . The method of claim 149 , wherein the CAR hinge region comprises one or more cysteines substituted with a different amino acid.