The invention relates to a method for the in vitro generation of antigen-specific antibodies or cells producing thereof, said method comprising culturing B cells with an antigen-coated carrier for at least 3 days, wherein said antigen-coated carrier has a size between 0.5 µm and 20 µm, and co-culturing the B cells obtained from step a) with CD4+ T cells for at least 3 days. Thus, high-affinity class-switched immunoglobulins of clinical and diagnostic interest are produced in vitro.