Modulating human Cas9-specific host immune response
Provided herein are methods and compositions for reducing an undesirable T cell immune response in human patients prior to and/or during gene therapy using CRISPR/Cas9-based genetic modulation.
1. A method of altering the expression of at least one gene product in a subject, the method comprising:
introducing into a cell from the subject an engineered Type II CRISPR-Cas system comprising a Cas9 protein and at least one guide RNA that hybridizes to a target sequence within a DNA molecule that encodes the at least one gene product in the cell, wherein the Cas9 protein comprises the amino acid sequence of SEQ ID NO:3 or SEQ ID NO:4, wherein the Cas9 protein has decreased immunogenicity as compared to the Cas9 protein of SEQ ID NO:1, and wherein expression of the at least one gene product is altered.
2. The method of claim 1 , wherein the introducing step is performed ex vivo or in vivo.
3. The method of claim 1 , further comprising screening a sample from the subject to detect the presence of an immune response to Cas9 in the subject.
4. The method of claim 3 , wherein the sample comprises peripheral blood mononuclear cells.
5. The method of claim 1 , wherein the Cas9 protein comprises the amino acid sequence of SEQ ID NO: 3.
6. The method of claim 1 , wherein the Cas9 protein comprises the amino acid sequence of SEQ ID NO: 4.