CD40LG and infection: -Check vaccinations (specially hepatitis B vaccine) and infection risks (including tuberculosis) before initiation. Avoid live vaccines.-Pretreatment prior to infusion with antihistamines, antipyretics and corticosteroids-CD19 control at 2,4,and 6 months.-Laboratory control with cell blood count, IgG, IgM, and IgA every 3 months.-Contraception.