If I have antiphospholipid syndrome, can I donate blood?

No, maybe for self. Aps is an autoimmune disease and antibodies are present in blood. Experiments of injecting serum (blood product) from aps patients to mice caused different changes in hyperactivity compared to normal serum or placebo. Aps may not be infectious but transient systemic effects can occur because of the presence of different anti phospholipid antibodies in the blood donation. Autologous donation is ok!