BCR and autoimmune thrombocytopenic purpura: Taking advantage of this novel method, we investigated the repertoires of IgG-BCRs of peripheral blood B cells from ITP patients in order to identify the characteristics of IgG-BCR repertoires in this disorder, and were able to find the oligoclonal expansions of IGHV4–28/IGHJ4-carrying IgG-expressing B cells with small clonal sizes.