For instance, exosomes can bind to an anti-CD22 monoclonal antibody fragment (CD22-F (ab’) 2) and wrap doxorubicin (DOX) to form CD22-F (ab’) 2-Exo-DOX, which can penetrate the BBB and accurately deliver DOX to lymphoma cells of primary central nervous system, thus enhancing anti-tumor activity in tumor-bearing mice [58]. The gene discussed is CD22; the disease is lymphoma.