The invention provides a system for use in immunotherapy for reducing the side-effects of an antigen-recognizing receptor against antigen-expressing non-target cells in an individual, comprising a) Said antigen-recognizing receptor wherein said antigen-recognizing receptor specifically recognizes an antigen on target cells in said individual b) Hematopoietic cells resistant to recognition of said antigen by said antigen-recognizing receptor wherein said antigen is expressed on target cells in said individual and at least on one hematopoietic cell type of said individual.
