ZAP70 and leukemia: To confirm the necessity of tethering SLP-76 to the membrane versus overexpression of cytosolic proximal signaling molecules in vivo, we compared MT-SLP-76 to overexpression of cytosolic SLP-76 or ZAP-70 in this model and found that only MT-SLP-76 restored functionality against CD22-low leukemia (Extended Data Fig. 3c).