Fig. 1.

Clinical course associated with the recovery of T and B lymphocytes (a) and serum levels of immunoglobulins (b) in the admitted period. a The clinical course was illustrated. Reduced intensity conditioning (RIC) consisted of fludarabine (FLU), cyclophosphamide (CY), and 3 Gy of total body irradiation (TBI). Anti-thymocyte globulin (ATG, Thymoglobulin, Sanofi) was added for the purpose of prophylaxis for rejection and graft-versus-host disease (GVHD). GVHD prophylaxis consisted of cyclosporine (CsA) and mycophenolate mofetil (MMF). The numbers of CD3⁺ (solid gray) and CD19⁺ (dotted gray) lymphocytes in the peripheral blood (PB) were followed in the admitted period. b Serum immunoglobulin levels in the admitted period were plotted. Whereas IgA (solid gray) and IgM (dotted gray) were not detected before allo-SCT, the titers of both rapidly increased within 1 week of allo-SCT and peaked on day 20. Anti-B antibodies (the blood type of the recipient and donor was A+) were also detected as early as day 10. IgG (solid black) levels decreased after the discontinuation of IgG replacement therapy and were maintained at more than 500 mg/dL