 Since one of the mechanisms of action of the monoclonal antibodies is to promote ADCC , our hypothesis is that the treatment with a suspension of autologous effector lymphocytes expanded ex-vivo with culture should modify the biological effect of the treatment with rituximab in follicular lymphoma patients, with an acceptable safety profile, and probably increasing the efficiency of the monoclonal antibodies. In order to evaluate this hypotesis we propose an open, prospective, historically controlled, phase II clinical study in patients with follicular lymphoma who have achieved a remission after first-line therapy including the anti-CD20 monoclonal antibody rituximab and chemotherapy. 