Besides secretion of antigen-specific antibodies, B cells may play an important role in the generation of immune responses by efficiently presenting antigen to T cells. We and others recently described a subpopulation of CD11c+ B cells (Age/autoimmune associated B cells, ABCs) which appear with age, during virus infections and at the onset of some autoimmune diseases and which participate in autoimmune responses by secreting autoantibodies. Here we assessed the ability of these cells to present antigen and activate antigen-specific T cells. We demonstrated that ABCs present antigen to T cells, in vitro and in vivo, better than follicular B cells (FO cells) do. Our data indicate that ABCs express higher levels of the chemokine receptor, CCR7, and have higher responsiveness to CCL21 and CCL19 than FO cells and are localized at T/B cell border in spleen. Using multiphoton microscopy we show that, in vivo, CD11c+ B cells form significantly more stable interactions with T cells than Follicular B cells do. Together these data identify a previously undescribed role for ABCs as potent antigen-presenting cells and suggest another potential mechanism by which these cells can influence immune responses and/or the development of autoimmunity.