The manufacturing process of CAR T cells involves several key steps: 1. Leukapheresis: Blood is drawn from the patient and T cells are separated. 2. Genetic Engineering: The T cells are transduced with a viral vector that encodes the CAR gene. 3. Expansion: The genetically modified T cells are cultured and expanded. 4. Preparation for Infusion: The cells are purified and prepared for re-infusion into the patient.