Given growing evidence that commonly used immunosuppressant drugs such as the calcineurin inhibitors, can modulate AD‐associated pathologies, 3xTg‐AD mice were immunosuppressed with a recently described recombinant antibody approach that targets the T‐cell costimulatory molecules, LFA‐1, CD40, and CTLA‐4 (Pearl et al., 2011). This evidence concerns the gene CTLA4 and Alzheimer disease.