 The present clinical assay proposes to study the feasibility, safety and effectiveness of treatment with autologous effector cells expanded ex vivo associated with a standard maintenance treatment with rituximab in patients with follicular lymphoma in remission after first-line treatment. In addition, we plan to analyse various biological parameters that can predict the susceptibility of patients to treatment with rituximab. Specifically, we propose to study the polymorphisms of Fc receptor, polymorphisms related to the ability of complement activation, to study both the complement activity and peripheral blood cell subpopulations that can mediate directly or indirectly dependent antibody cytotoxic effect. We will also try to correlate any of these biological parameters with the response to treatment. 