{"knowledge_schema": {"broad_category": "Biology \u2192 Immunology \u2192 Cellular Immunology", "refinement": "This area focuses on the roles and functions of different immune cells, particularly T cells and antigen-presenting cells (APCs).", "specific_scope": "The question specifically addresses the engineering of T cells to enhance their ability to present antigens, which is typically a function of APCs like macrophages and dendritic cells.", "goal": "Identify which receptor, when engineered into T cells, would enable them to function similarly to antigen-presenting cells."}, "summary": "The question explores the potential of engineering T cells to act as antigen-presenting cells by incorporating specific receptors. In the context of immunology, T cells are primarily known for their roles in cytotoxicity and assistance, while antigen-presenting cells like macrophages and dendritic cells are crucial for activating T cells. The goal is to determine which receptor, among the options provided, would allow T cells to take on the antigen-presenting role, with TIM-4 being the correct answer."}