Yuji Miura

Successful treatment of Epstein-Barr virus-associated natural killer cell large granular lymphocytic leukaemia using allogeneic peripheral blood stem cell transplantation

We report a case of natural killer cell large granular lymphocytic (NK-LGL) leukaemia successfully treated with allogeneic peripheral blood stem cell transplantation (allo-PBSCT). The peripheral blood (PB) revealed an abnormal expansion of LGL that were CD3−, CD16− and CD56+, and had natural killer activity. In situ EBER-1 hybridization of the PB mononuclear cells showed the presence of Epstein–Barr virus (EBV) in the LGL as well as in lymphocytes infiltrating the tonsils and colon. Southern blotting with an EBV-terminal repetitive sequence probe demonstrated clonal proliferation of EBV+ cells. The patient received allo-PBSCT from his HLA-matched sister with a conditioning regimen involving the use of cyclophosphamide and fractionated total body irradiation. The patient promptly recovered trilineage haematopoiesis without graft-versus-host disease, and has been in complete remission without therapy for 10 months since allo-PBSCT, suggesting that allo-PBSCT could eradicate the NK-LGL leukaemic cells.

Administration of G-CSF to normal individuals diminishes L-selectin + T cells in the peripheral blood that respond better to alloantigen stimulation than L-selectin - T cells

To determine whether administration of G-CSF induces phenotypic or functional changes in T cells, we examined peripheral blood T cells from normal individuals receiving G-CSF for activation antigen and adhesion molecule expression before and after G-CSF administration. G-CSF (10 μg/kg/day) was administered subcutaneously to 14 normal individuals for 3–5 days and their PBMC were serially analyzed with monoclonal Ab (mAb) directed to HLA-DR, CD45RO, CD45RA, CD25, CD122, CD95, CD11a, CD49d, CD44 and CD62L (L-selectin) coupled with anti-CD3 mAb. Among T cells positive for these antigens, only the proportion of T cells expressing L-selectin significantly decreased from 68% to 37% after 3-day G-CSF administration. When peripheral blood CD3+ T cells obtained before and after G-CSF administration were sorted into two populations depending on the expression of L-selectin and tested for their proliferative response to allogeneic B cells, the reactivity of L-selectin− cells to alloantigen stimulation was consistently lower than that of L-selectin+ cells regardless of the exposure to G-CSF. The decrease in the relative number of L-selectin+ cells induced by G-CSF administration may contribute to the unexpectedly low incidence of severe acute GVHD after allogeneic PBSC transplantation.

Early establishment of hematopoietic chimerism following allogeneic peripheral blood stem cell transplantation in comparison with allogeneic bone marrow transplantation

Abstract:  To characterize the process of the establishment of complete chimerism after allogeneic peripheral blood stem cell transplantation (allo‐PBSCT), we determined the origin of leukocytes in peripheral blood (PB) obtained from 23 patients in the very early period after allo‐PBSCT using amplification of mini‐ or microsatellite regions of genomic DNA. Donor‐specific alleles were amplified from the PB obtained at day 8 post‐transplant for 19 allo‐PBSCT patients. Among the 19 patients, 12 showed only donor‐specific alleles (complete chimerism) while 7 did both donor and host‐specific alleles (mixed chimerism). Although donor specific alleles were amplified in 10 of 12 patients who received allogeneic bone marrow transplantation (allo‐BMT) similarly to allo‐PBSCT, all of these ten showed mixed chimerism. When the chimeric state was examined in PB samples obtained serially at 2–3‐day intervals post‐transplant, host‐specific alleles in allo‐PBSCT patients were not detectable in the PB much earlier than those in allo‐BMT patients. These findings indicate that the appearance of donor‐derived cells associated with the disappearance of host‐derived cells in the circulation occurs earlier after allo‐PBSCT as compared with allo‐BMT, leading to the rapid establishment of complete chimerism.

Enhancement of cyclosporin A-induced autologous graft-versus-host disease after peripheral blood stem cell transplantation by utilizing selected CD34 + cells

Summary:Although autologous graft-versus-host disease (GVHD) can be induced by administration of cyclosporin A (CsA) after peripheral blood stem cell transplantation (PBSCT), the incidence appears to be remarkably lower compared to the incidence after bone marrow transplantation. The reduced incidence of autologous GVHD after PBSCT may be attributed to peripheral regulatory cells that are transferred with the stem cell inoculum. To determine whether transplantation of CD34-selected peripheral blood stem cells (PBSCs) leads to potentiation of autologous GVHD, five patients with malignant lymphoma were transplanted with CD34-selected PBSCs, followed by administration of CsA and interferon (IFN)-γ. Inducibility of autologous GVHD and autocytotoxic activities of peripheral blood mononuclear cells (PBMCs) after transplantation were assessed. All patients demonstrated prompt hematologic recovery. Cytotoxic activity of PBMCs against autologous lymphocytes was detectable in four of four patients analyzed during a limited period from days 14 to 34 post-transplant. An erythematous rash compatible with GVHD, confirmed by skin biopsy, developed in three of five patients. One of the three patients developed not only skin, but also gut and liver GVHD. Transplantation of the CD34-selected stem cell graft that does not accompany transfusion of regulatory cells may potentiate the inducibility of autologous GVHD by the administration of CsA and IFN-γ.

Successful treatment of B-cell lymphoma associated with hemophagocytic syndrome using autologous peripheral blood CD34 positive cell transplantation followed by induction of autologous graft-versus-host disease.

Abstract A 56-year-old man who presented with persistent high fever and abdominal pain was diagnosed as having a B-cell lymphoma associated with hemophagocytic syndrome (B-LAHS). As post-remission therapy, the patient was treated with high-dose chemoradiotherapy followed by infusion of autologous CD34+ cells that had been isolated from the peripheral blood buffy coat. Cyclosporin and interferon (IFN)-γ were administered to induce autologous graft-versus-host disease (GVHD). Hematopoietic recovery promptly occurred and skin GVHD developed on day 26 after CD34+ cell transplantation. The patient has been in complete remission without therapy for 20 months since transplant. Autologous CD34+ cell transplantation in combination with induction of autologous GVHD may be efficacious in obtaining a cure for B-LAHS.

Induction of autocytotoxic T cells with cyclosporine and interferon-γ for patients with non-Hodgkin's lymphoma after transplantation of peripheral blood stem cells

BACKGROUND Autologous graft-versus-host disease is inducible after autologous bone marrow transplantation by means of administration of cyclosporine. OBJECTIVE This study was performed to investigate the inducibility of autologous graft-versus-host disease after transplantation of peripheral blood stem cells (PBSCs). METHODS Two patients with non-Hodgkins lymphoma in remission underwent PBSC transplantation followed by administration of cyclosporine and low-dose interferon-gamma. RESULTS Although autologous graft-versus-host disease did not develop in either patient, T lymphocytes with cytotoxic activity against autologous lymphocytes appeared transiently in the early posttransplant period. Such autocytotoxic lymphocytes were not detectable in another patient who underwent PBSC transplantation who did not receive cyclosporine and interferon-gamma. When CD4+ and CD8+ cells were sorted from the peripheral blood mononuclear cells of one of the two patients and tested for cytotoxicity against autologous lymphocytes, only CD8+ cells exhibited cytotoxic activity. CONCLUSIONS The results indicate that administration of cyclosporine and interferon-gamma after PBSC transplantation can induce autocytotoxic CD8+ T cells, even though it may not produce autologous graft-versus-host disease. It is unclear whether induction of such autocytotoxic T cells among patients with non-Hodgkins lymphoma who undergo PBSC transplantation has any antilymphoma effect.