The present invention includes compositions and methods for modifying a T cell with a nucleic acid encoding a switch molecule comprising an extracellular domain comprising a membrane receptor or fragment thereof and an intracellular domain comprising a signaling receptor or fragment thereof. In one aspect, a method comprises introducing a nucleic acid encoding a switch molecule and a nucleic acid encoding a soluble fusion protein and/or a nucleic acid encoding a bispecific antibody into a population of cells comprising T cells, wherein the T cells transiently expresses the switch molecule and soluble fusion protein or bispecific antibody. In other aspect, compositions of T cells and methods of treating a disease or condition, such as cancer or an autoimmune disease, are also included.