Yukari Takeda

Hypogammaglobulinemia with a selective delayed recovery in memory B cells and an impaired isotype expression after rituximab administration as an adjuvant to autologous stem cell transplantation for non-Hodgkin lymphoma.

Abstract:  Objectives: Some studies have indicated patients who received rituximab as adjuvant to stem cell transplantation had an increased risk of developing severe hypogammaglobulinemia. The mechanism of this hypogammaglobulinemia is unknown, although investigators have hypothesized a further delay in the B‐cell recovery as one potential etiology. The aim of this study is to clarify the mechanism(s) of this hypogammaglobulinemia. Methods: A total of 14 patients with high‐risk CD20+ lymphoma underwent an autologous peripheral blood stem cell transplantation (APBSCT). After a hematological recovery, rituximab was given weekly for up to four doses as an adjuvant therapy. Results: After a median follow up of 33.5 months, we found six patients (group A) who had hypogammaglobulinemia, while the eight other patients (group B) had normal serum immunoglobulin levels. A phenotypical analysis revealed that group A patients had already achieved B‐cell recovery. However, we found a severe delay in the recovery of CD27+ memory B cells, especially in the IgD−/CD27+ switched populations in group A, but CD27 negative naive B‐cells reverted to a normal range in both groups. Consistent with this, reverse transcriptase‐polymerase chain reaction studies with peripheral blood mononuclear cells revealed that most patients in group A lacked more than two classes of isotype transcripts. Conclusions: Abnormal repertoires and impaired isotype expression are seen in patients with common variable immunodeficiency, these data suggested that rituximab after APBSCT can affect not only the B‐cell quantities, but also the recovery of the B‐cell repertoires.

Excellent Outcome of Allogeneic Hematopoietic Stem Cell Transplantation Using a Conditioning Regimen with Medium-Dose VP-16, Cyclophosphamide and Total-Body Irradiation for Adult Patients with Acute Lymphoblastic Leukemia

We retrospectively evaluated the outcomes of 37 adult patients with acute lymphoblastic leukemia (ALL) undergoing allogeneic hematopoietic stem cell transplantation (allo-SCT) conditioned with medium-dose VP-16 (VP, 30 mg/kg), cyclophosphamide (CY, 120 mg/kg), and fractionated total-body irradiation (TBI, 12 Gy) (medium-dose VP/CY/TBI). The median age of the patients was 26 years. Thirteen patients underwent transplantation from HLA-matched related donors (MRD), 18 patients underwent transplantation from HLA-matched unrelated donors (MUD), and 6 patients underwent transplantation from HLA-mismatched donors (MMD). Thirty-two patients received bone marrow and 4 patients received peripheral blood stem cells. Ten patients were Philadelphia chromosome-positive (Ph(+)) and 35 patients were in complete remission (CR) at transplantation. All of the patients achieved engraftment, and grade 3 organ toxicity before engraftment occurred in 27 patients. Grade II-III acute graft-versus-host disease (GVHD) and chronic GVHD (cGVHD) occurred in 15 and 18 patients, respectively. No patient developed grade IV acute GVHD (aGVHD) or died of GVHD. At median follow-up of 35.1 months, 32 patients were alive and all Ph(+) patients were alive. Three patients died of relapse and 2 died of transplant-related mortality (TRM). The actuarial 3-year overall survival (OS) rate, relapse rate, and TRM rate were 89.2%, 8.1%, and 5.4%, respectively. Non-CR at transplantation, MRD, and no aGVHD were significant adverse prognostic factors for survival. Medium-dose VP/CY/TBI for adult ALL patients was associated with lower relapse rate and no increase in toxicity, resulting in better survival.

Delayed redistribution of CD27, CD40 and CD80 positive B cells and the impaired in vitro immunoglobulin production in patients with non-Hodgkin lymphoma after rituximab treatment as an adjuvant to autologous stem cell transplantation

Recent studies have indicated that patients who received rituximab as an adjuvant to stem cell transplantation (SCT) demonstrated an increased risk of developing severe hypogammaglobulinaemia, which was found to be a result of delayed recovery of CD27 positive memory B cells and impaired isotype expression. It appears that rituximab influences both the quantity and quality of B‐cell redistribution. Precisely how the B‐cell repertoire regenerates after anti‐CD20‐mediated transient B‐cell depletion in patients with non‐Hodgkin lymphoma (NHL) remains to be elucidated. This study performed a phenotypical analysis of B cells in 17 NHL patients who received rituximab as an adjuvant to autologous SCT. The median period after final administration of rituximab was 36 months (range, 12–43 months). Surface antigen expression of CD27, CD40 and CD80 in NHL patients was statistically significantly different from healthy controls (n = 14). Moreover, B cells from NHL patients showed significantly impaired IgG and IgA production upon engagement of surface immunoglobulin receptors in the presence of interleukin (IL)‐2, IL‐10 and CD40 ligand in comparison with samples from healthy controls. The delayed recovery of memory B cells with an abnormal cell marker expression and function demonstrates that naive B cells may fail to differentiate into plasma cells, resulting in hypogammaglobulinaemia after autologous SCT and rituximab therapy.

Therapeutic impact of human bone marrow stromal cells expanded by animal serum-free medium for cerebral infarct in rats.

BACKGROUND:The donor cell culture in animal serum-free medium is important for the clinical application of cell transplantation therapy. Recently, human-derived platelet lysate (PL) gained interest as a substitute for fetal calf serum (FCS), but there are no studies that evaluate the validity of human bone marrow stromal cells (hBMSCs) expanded with PL-containing medium for central nervous system disorders. OBJECTIVE:To test the hypothesis that hBMSCs expanded with FCS-free, PL-containing medium can promote functional recovery after cerebral infarct. METHODS:hBMSCs were cultured in the FCS- or PL-containing medium. Cell-growth kinetics were analyzed. The vehicle or hBMSCs was stereotactically transplanted into the ipsilateral striatum of the rats subjected to permanent middle cerebral artery occlusion 7 days after the insult. Motor function was assessed for 8 weeks, and the fate of transplanted hBMSCs was examined using immunohistochemistry. RESULTS:There was no significant difference in hBMSC expansion between the 2 groups. Transplantation of hBMSCs expanded with the FCS- or PL-containing medium equally promoted functional recovery compared with the vehicle group. Histological analysis revealed that there were no significant differences in their migration, survival, and neural differentiation in the infarct brain between the 2 groups. CONCLUSION:hBMSCs expanded with PL-containing medium retained their capacity of migration, survival, and differentiation and significantly promoted functional recovery when stereotactically transplanted into the infarct brain. The PL may be a clinically valuable and safe substitute for FCS in expanding hBMSCs to regenerate the infarct brain.

FCGR3A-158V/F polymorphism may correlate with the levels of immunoglobulin in patients with non-Hodgkin’s lymphoma after rituximab treatment as an adjuvant to autologous stem cell transplantation

Objectives:  Recent studies have indicated that patients who receive stem cell transplantation (SCT) and rituximab demonstrate an increased risk of developing hypogammaglobulinemia. Such hypogammaglobulinemia has been found to be due to delayed recovery of memory B cells with an abnormal cell marker expression and impaired immunoglobulin production in vitro. However, no predictive factors for the levels of immunoglobulin after autologous SCT and rituximab therapy have been reported. The aim of this study is to clarify the relationships between the FCGR3A‐158V/F genotype and the levels of serum immunoglobulin after SCT.

Biological Features of Human Bone Marrow Stromal Cells (hBMSC) Cultured with Animal Protein-Free Medium—Safety and Efficacy of Clinical Use for Neurotransplantation

The donor cell culture in animal serum-free medium is quite important for the clinical application of cell transplantation therapy. This study was aimed to test the hypothesis that the human bone marrow stromal cells (hBMSC) expanded with fetal calf serum (FCS)-free, platelet lysate (PL)-containing medium retain their biological features favoring central nervous system regeneration. The hBMSC were cultured with 5% PL or 10% FCS. Their phenotypes were analyzed with flow cytometry, and their production of growth factors was quantified with enzyme-linked immunosorbent assay. Their capacity of neural differentiation was verified by immunocytochemistry. There was no significant difference in morphology and cell surface marker between the hBMSC–FCS and hBMSC–PL. Both of them were positive for CD44, CD90, CD105, and CD166 and were negative for CD34, CD45, and CD271. The production of human brain-derived neurotrophic factor, human hepatocyte growth factor, human β-nerve growth factor, and human platelet-derived growth factor-BB did not differ between the two groups, although the hBMSC–PL produced significantly more amount of TGF-β1 than the hBMSC–FCS. There was no significant difference in their in vitro differentiation into the neurons and astrocytes between the two groups. The hBMSC expanded with PL-containing medium retain their biological capacity of neural differentiation and neuroprotection. The PL may be a clinically valuable and safe substitute for FCS in expanding the hBMSC for cell therapy.

Complete remission of splenic marginal zone lymphoma after an acute flare-up of hepatitis B in a hepatitis B virus carrier.

A 44-year-old female presented with asymptomatic leukocytosis and moderate splenomegaly. The diagnosis of splenic marginal zone lymphoma (SMZL) was made by a splenectomy. A virological examination revealed the patient to be a hepatitis B virus (HBV) carrier. The lymphocyte count in her peripheral blood decreased after splenectomy, but remained high for 2 years and bone marrow infiltration was obvious. Two years after the splenectomy, she was admitted for an acute flare-up of hepatitis B. The liver dysfunction improved without any medication and thereafter returned to the normal range within a few weeks. At the same time, the lymphocyte count in her peripheral blood rapidly decreased to normal levels. Atypical lymphocytes disappeared from the peripheral blood and bone marrow aspirates and biopsy specimen revealed complete remission of SMZL, including the disappearance of the clonal rearrangement of IgH-JH. There has been no recurrence of acute hepatitis and she has been in complete remission for SMZL for more than 6 years. The clinical course of this patient suggests that an immune response against HBV also affects the clearance of lymphoma cells. This is the first report that a complete remission was achieved in a patient with SMZL after a hepatitis B flare-up.

Sequential chemotherapy and myeloablative allogeneic hematopoietic stem cell transplantation for refractory acute lymphoblastic leukemia

The prognosis of patients receiving allogeneic hematopoietic stem cell transplantation (HSCT) for refractory acute lymphoblastic leukemia (ALL) is very poor. To improve survival rates, we attempted to intensify the conditioning regimen with daunorubicin, vincristine, prednisolone, medium-dose etoposide, cyclophosphamide, and total body irradiation (DNR/VCR/PSL plus medium-dose VP/CY/TBI). Four patients in relapse or induction failure of B-precursor ALL without other complications underwent allogeneic HSCT. Initially, chemotherapy comprising DNR 60 mg/m2 for 3 days, VCR 1.4 mg/m2 for 1 day, and PSL 60 mg/m2 for 3 days was administered, which was followed by medium-dose VP/CY/TBI; some modifications were made for individual patients. All patients achieved engraftment and complete remission after HSCT. Regimen-related toxicities were tolerable and no patient died within 100 days. Two patients were alive without disease on days 563 and 1,055. The third patient relapsed on day 951, while the fourth died on day 179 without disease. Our results indicate that intensified myeloablative HSCT should be considered for patients with refractory ALL.

Cord blood transplantation with a reduced-intensity conditioning regimen for patients with relapsed aggressive multiple myeloma after cytoreduction with bortezomib

Two multiple myeloma patients relapsed after autologous stem cell transplantation (ASCT). Conventional chemotherapy, including thalidomide, showed very little effect, but both patients responded well to a standard dose of bortezomib. One patient was treated with two additional cycles of bortezomib, but his clinical course suddenly deteriorated. Unrelated cord blood transplantation (CBT) with reduced-intensity conditioning regimen (RIC) was performed in refractory disease. After CBT, the clinical course was aggravated by tumor lysis syndrome and other conditions, thus resulting in patient death on day 34. Thereafter, we administered CBT with RIC on the second patient after just one course of bortezomib therapy since she was in partial remission. The second patient developed acute and chronic GVHD, and both responded to the steroid therapy. She has been in complete remission for more than 48 months after CBT. These results suggested that the timing of CBT with RIC may be very important, and cytoreduction with not only ASCT but also bortezomib could give a promising chance for a successful CBT.