No increased mortality from donor or recipient hepatitis B- and/or hepatitis C-positive serostatus after related-donor allogeneic hematopoietic cell transplantation.

Limited data exist on allogeneic transplant outcomes in recipients receiving hematopoietic cells from donors with prior or current hepatitis B (HBV) or C virus (HCV) infection (seropositive donors), or for recipients with prior or current HBV or HCV infection (seropositive recipients). Transplant outcomes are reported for 416 recipients from 121 centers, who received a human leukocyte antigen-identical related-donor allogeneic transplant for hematologic malignancies between 1995 and 2003. Of these, 33 seronegative recipients received grafts from seropositive donors and 128 recipients were seropositive. The remaining 256 patients served as controls. With comparable median follow-up (cases, 5.9 years; controls, 6.7 years), the incidence of treatment-related mortality, survival, graft-versus-host disease, and hepatic toxicity, appears similar in all cohorts. The frequencies of hepatic toxicities as well as causes of death between cases and controls were similar. Prior exposure to HBV or HCV in either the donor or the recipient should not be considered an absolute contraindication to transplant.

Bone marrow origin of hepatic macrophages (Kupffer cells) in humans.

Hepatic macrophages (Kupffer cells) from two male recipients of bone marrow transplants from females were studied for fluorescent Y body staining and sex chromatin (Barr body). After the transplant, macrophages had the sex karyotype of the donor, indicating that human hepatic macrophages originate in bone marrow.

Opioid peptides mediate the suppressive effect of stress on natural killer cell cytotoxicity.

The cytotoxic activity of natural killer cells was investigated in rats subjected to one of two inescapable footshock stress paradigms, both of which induce analgesia, but only one via activation of opioid mechanisms. Splenic natural killer cell activity was suppressed by the opioid, but not the nonopioid, form of stress. This suppression was blocked by the opioid antagonist naltrexone. Similar suppression of natural killer activity was induced by high doses of morphine. These results suggest that endogenous opioid peptides mediate the suppressive effect of certain forms of stress on natural killer cell cytotoxicity.

Allogeneic hematopoietic cell transplantation for metastatic breast cancer.

We reviewed 66 women with poor-risk metastatic breast cancer from 15 centers to describe the efficacy of allogeneic hematopoietic cell transplantation (HCT). Median follow-up for survivors was 40 months (range, 3-64). A total of 39 patients (59%) received myeloablative and 27 (41%) reduced-intensity conditioning (RIC) regimens. More patients in the RIC group had poor pretransplant performance status (63 vs 26%, P=0.002). RIC group developed less chronic GVHD (8 vs 36% at 1 year, P=0.003). Treatment-related mortality rates were lower with RIC (7 vs 29% at 100 days, P=0.03). A total of 9 of 33 patients (27%) who underwent immune manipulation for persistent or progressive disease had disease control, suggesting a graft-vs-tumor (GVT) effect. Progression-free survival (PFS) at 1 year was 23% with myeloablative conditioning and 8% with RIC (P=0.09). Women who developed acute GVHD after an RIC regimen had lower risks of relapse or progression than those who did not (relative risk, 3.05: P=0.03), consistent with a GVT effect, but this did not affect PFS. These findings support the need for preclinical and clinical studies that facilitate targeted adoptive immunotherapy for breast cancer to explore the benefit of a GVT effect in breast cancer.

Antibody synthesis by bone marrow cells in vitro following primary and booster tetanus toxoid immunization in humans.

Normal volunteers received either initial or booster immunization with tetanus toxoid. Bone marrow and peripheral blood mononuclear cells were obtained for up to 28 d after immunization and were analyzed for synthesis of total Ig and specific antibodies to tetanus toxoid. Cells were cultured in vitro for 3 or 7 d with or without pokeweed mitogen (PWM). Synthesis of IgG and IgM antibodies to tetanus (IgG-Tet and IgM-Tet) and total IgG and IgM was determined by radioimmunoassay. Four functional B cell subpopulations were detected in the bone marrow after booster tetanus immunization: (a) B cells that spontaneously synthesized IgG-Tet appeared on day 7 after immunization but were undetectable by day 21; (b) B cells that synthesized IgG-Tet after stimulation with PWM appeared after day 21 and persisted for greater than 1 mo; (c) B cells that synthesized IgM-Tet in the presence of PWM were detectable before and after immunization; and (d) B cells that spontaneously synthesized IgM-Tet appeared on day 7 and were undetectable by day 21. In contrast to the other three types of bone marrow B cells described, this fourth subpopulation of PWM-independent IgM-Tet-synthesizing B cells was not detected in the peripheral blood. After primary immunization, no spontaneous antibody-producing cells were detected in the blood or bone marrow, although there was a small rise in IgM-Tet in two of three subjects. In the bone marrow, only IgM-Tet PWM-inducible cells were seen, although mitogen-responsive IgM and IgG-Tet cells were detected in the circulation. The IgM-Tet PWM-reactive cells were present even before primary antigen exposure and appear to represent the initial B cells involved in the antibody response. These data indicate that there are specific times after immunization when different functional classes of anti-Tet-synthesizing B cells and memory B cells appear in human bone marrow. Knowledge of these data may be important in developing a strategy for the transfer of immune memory from donors to recipients in the setting of bone marrow transplantation.

In vitro hepatitis B virus infection of human bone marrow cells.

Infection of humans with hepatitis B virus (HBV) frequently results in suppression of hematopoiesis; in some cases this may lead to severe bone marrow failure. The mechanism whereby HBV infection affects hematopoiesis is unknown. In vitro exposure of human bone marrow to HBV results in a dose-dependent inhibition of erythroid (erythroid burst forming units, BFU-E; erythroid colony-forming units CFU-E), myeloid (colony-forming units-granulocyte macrophage CFU-GM), and lymphoid (CFU-[T-lymphocytic]-TL) hematopoietic stem cells. Inactivation or immunoabsorption of HBV from sera resulted in loss of HBV-induced inhibition of hematopoietic stem cells. De novo gamma interferon was not detectable in the supernatants of cultures of bone marrow cells with HBV. Antibodies to gamma interferon did not affect the suppression of hematopoietic stem cells by HBV. Hepatitis B surface antigen (HBsAg) was detected by immune electron microscopy in nuclei of greater than 70% of immature hematopoietic cells including myeloblasts, normoblasts, and lymphoblasts; granulocytes had mostly cytoplasmic HBsAg. Hepatitis B virus core antigen (HBcAg) was also detected in about 5% of HBV infected bone marrow cells by immunoperoxidase staining. These data indicate that HBV can infect hematopoietic cells and their progenitors, thus suggesting a wider range of tropism for HBV than previously reported. These results may provide a basis to study HBV infection in vitro, and the effects of HBV on hematopoiesis.

Abnormalities of myeloid progenitor cells after "successful" bone marrow transplantation.

We studied recovery of peripheral blood- and bone marrow-derived myeloid progenitor cells (CFU-G,M) in 29 patients who received bone marrow transplants 2 mo to 8.5 yr previously. All patients had normal levels of peripheral blood neutrophils, normal bone marrow cellularity, and a normal myeloid-erythroid ratio. Both peripheral blood- and bone marrow-derived CFU-G,M were markedly reduced compared with normal controls and bone marrow donors [5 +/- 1/10(6) vs. 37 +/- 4/10(6) (P less than 0.001) and 23 +/- 5/2 x 10(5) vs. 170 +/- 21/2 x 10(5) (P less than 0.001)]. Five patients had no detectable CFU-G,M even when 10(6) bone marrow cels were plated. These abnormalities of CFU-G,M were unrelated to age, sex, diagnosis, conditioning regimen, dose of bone marrow cells transplanted, and presence or absence of graft-vs.-host disease. Patients who received either autotransplants or transplants from identical twins also had decreased or absent CFU-G,M indicating that allogeneic factors and posttransplant immune suppressor with methotrexate or corticosteroids were not major determinants of this abnormality. Co-culture of normal or donor peripheral blood or bone marrow mononuclear cells with recipients peripheral blood or bone marrow mononuclear cells, purified T cells, or serum failed to show any evidence of active CFU-G,M suppression. Furthermore, the abnormality of CFU-G,M could not be corrected by the addition of normal syngeneic (donor) hematopoietic cells or serum. Depletion of T-cells from recipient bone marrow by physical techniques resulted in marked increase in CFU-G,M (36 +/- 13 vs. 138 +/- 36; P less than 0.05). The abnormality could be reproduced in vitro by readdition of autologous T cells. In contrast to results with T cell depletion by physical techniques, T cell depletion with a monoclonal anti-T antibody (B7) and complement had no effect. These data indicate that most-transplant recipients have a marked abnormality in CFU-G,M when these cells are cultured in vitro. In at least some of these patients, the decreased cloning efficiency of CFU-G,M appears to be mediated by a suppressive effect of autologous T cells.

Thymus-dependent lymphocytes in human bone marrow.

Human bone marrow is known to contain significant numbers of bursa-dependent lymphocytes. The presence of thymus-dependent (T) cells is controversial. Bone marrow cells obtained from healthy volunteers was fractionated by density centrifugation. A lymphocte-enriched subpopulation was shown to be reactive to alloantigens in mixed lymphocyte culture and to contain substantial numbers of T lymphocytes. The T lymphocytes were detected by cell surface markers (rosette formation with sheep RBC) and by response to the mitogens phytohemagglutinin and concanavalin A. Bone marrow T cells exhibited functional characteristics quantitatively different from peripheral blood T cells, suggesting that they may represent a particular subpopulation of T cells. The lymphocyte-enriched fraction additionally contained committed granulopoietic stem cells capable of colony formation in semisolid gel. The presence of T cells in human bone marrow is consistent with findings in other mammals and may explain the high incidence of graft versus host disease in bone marrow transplant recipients.

Designed transfer of specific immune responses with bone marrow transplantation.

Bone marrow transplant donors were immunized with tetanus/diphtheria toxoids 6-7 d before bone marrow donation to investigate the role of B cell subpopulations in reconstitution of humoral immunity. Lymphoblastoid B cells spontaneously producing IgG antitetanus and/or antidiphtheria toxoid were detected in the donor marrows at the time of transplantation. Recipients rapidly demonstrated 3-90-fold increases in serum IgG antitetanus and antidiphtheria toxoid levels. Antidiphtheria fragment A antibody in three donor/recipient pairs demonstrated spectrotypic identity indicating transfer of the donors' response. Reimmunization of three recipients 64-154 d after transplant revealed an IgG antibody response associated with reappearance of spontaneous antibody-producing B cells and an antidiphtheria fragment A response characteristics of the donor's immune response. These observations extend the understanding of the role of B cell subpopulations and provide a basis for specific modulation of immunity in the setting of bone marrow transplantation.

Graft-versus-leukemia in chronic lymphocytic leukemia.

Immune-mediated anti-leukemia effects, often termed graft-versus-leukemia (GvL), operate after bone marrow or blood cell transplants for acute lymphoblastic leukemia, acute myelogenous leukemia and chronic myelogenous leukemia. Sometimes the magnitude of this anti-leukemia effect exceeds that of high-dose anti-leukemia drugs and radiation and can result in leukemia cure. We analyzed leukemia relapse data after transplants for chronic lymphocytic leukemia (CLL) in this context. These data support the notion of a strong GvL effect in CLL. However, as most of these data are from studies of allotransplants, it is uncertain whether GvL operates in settings where the anti-leukemia effector cells and target CLL cells are genetically identical except for leukemia-related mutations. It is also uncertain whether GvL is distinct from GvHD. These potential limitations have important implications on whether immune therapy of CLL will work in non-allotransplant settings.

Gemtuzumab ozogamicin in acute myeloid leukemia.

CD33 is variably expressed on leukemia blasts in almost all patients with acute myeloid leukemia (AML) and possibly leukemia stem cells in some. Efforts to target CD33 therapeutically have focused on gemtuzumab ozogamicin (GO; Mylotarg), an antibody-drug conjugate delivering a DNA-damaging calicheamicin derivative. GO is most effective in acute promyelocytic leukemia but induces remissions in other AML types and received accelerated approval in the US in 2000. However, because a large follow-up study showed no survival improvement and increased early deaths the drug manufacturer voluntarily withdrew the US New Drug Application in 2010. More recently, a meta-analysis of data from several trials reported better survival in adults with favorable- and intermediate-risk cytogenetics but not adverse-risk AML randomized to receive GO along with intensive induction chemotherapy. As a result, GO is being re-evaluated by regulatory agencies. Responses to GO are diverse and predictive biological response markers are needed. Besides cytogenetic risk, ATP-binding cassette transporter activity and possibly CD33 display on AML blasts may predict response, but established clinical assays and prospective validation are lacking. Single-nucleotide polymorphisms in CD33 may also be predictive, most notably rs12459419 where the minor T-allele leads to decreased display of full-length CD33 and preferential translation of a splice variant not recognized by GO. Data from retrospective analyses suggest only patients with the rs12459419 CC genotype may benefit from GO therapy but confirmation is needed. Most important may be markers for AML cell sensitivity to calicheamicin, which varies over 100 000-fold, but useful assays are unavailable. Novel CD33-targeted drugs may overcome some of GO's limitations but it is currently unknown whether such drugs will be more effective in patients benefitting from GO and/or improve outcomes in patients not benefitting from GO, and what the supportive care requirements will be to enable their safe use.

Measurable residual disease testing in acute myeloid leukaemia.

There is considerable interest in developing techniques to detect and/or quantify remaining leukaemia cells termed measurable or, less precisely, minimal residual disease (MRD) in persons with acute myeloid leukaemia (AML) in complete remission defined by cytomorphological criteria. An important reason for AML MRD-testing is the possibility of estimating the likelihood (and timing) of leukaemia relapse. A perfect MRD-test would precisely quantify leukaemia cells biologically able and likely to cause leukaemia relapse within a defined interval. AML is genetically diverse and there is currently no uniform approach to detecting such cells. Several technologies focused on immune phenotype or cytogenetic and/or molecular abnormalities have been developed, each with advantages and disadvantages. Many studies report a positive MRD-test at diverse time points during AML therapy identifies persons with a higher risk of leukaemia relapse compared with those with a negative MRD-test even after adjusting for other prognostic and predictive variables. No MRD-test in AML has perfect sensitivity and specificity for relapse prediction at the cohort- or subject levels and there are substantial rates of false-positive and -negative tests. Despite these limitations, correlations between MRD-test results and relapse risk have generated interest in MRD-test result-directed therapy interventions. However, convincing proof that a specific intervention will reduce relapse risk in persons with a positive MRD-test is lacking and needs testing in randomized trials. Routine clinical use of MRD-testing requires further refinements and standardization/harmonization of assay platforms and results reporting. Such data are needed to determine whether results of MRD-testing can be used as a surrogate end point in AML therapy trials. This could make drug-testing more efficient and accelerate regulatory approvals. Although MRD-testing in AML has advanced substantially, much remains to be done.

MYC is a positive regulator of choline metabolism and impedes mitophagy-dependent necroptosis in diffuse large B-cell lymphoma.

The activation of oncogenes can reprogram tumor cell metabolism. Here, in diffuse large B-cell lymphoma (DLBCL), serum metabolomic analysis revealed that oncogenic MYC could induce aberrant choline metabolism by transcriptionally activating the key enzyme phosphate cytidylyltransferase 1 choline-α (PCYT1A). In B-lymphoma cells, as a consequence of PCYT1A upregulation, MYC impeded lymphoma cells undergo a mitophagy-dependent necroptosis. In DLBCL patients, overexpression of PCYT1A was in parallel with an increase in tumor MYC, as well as a decrease in serum choline metabolite phosphatidylcholine levels and an International Prognostic Index, indicating intermediate-high or high risk. Both in vitro and in vivo, lipid-lowering alkaloid berberine (BBR) exhibited an anti-lymphoma activity through inhibiting MYC-driven downstream PCYT1A expression and inducing mitophagy-dependent necroptosis. Collectively, PCYT1A was upregulated by MYC, which resulted in the induction of aberrant choline metabolism and the inhibition of B-lymphoma cell necroptosis. Referred as a biomarker for DLBCL progression, PCYT1A can be targeted by BBR, providing a potential lipid-modifying strategy in treating MYC-High lymphoma.

A randomized study of pomalidomide vs placebo in persons with myeloproliferative neoplasm-associated myelofibrosis and RBC-transfusion dependence.

RBC-transfusion dependence is common in persons with myeloproliferative neoplasm (MPN)-associated myelofibrosis. The objective of this study was to determine the rates of RBC-transfusion independence after therapy with pomalidomide vs placebo in persons with MPN-associated myelofibrosis and RBC-transfusion dependence. Two hundred and fifty-two subjects (intent-to-treat (ITT) population) including 229 subjects confirmed by central review (modified ITT population) were randomly assigned (2:1) to pomalidomide or placebo. Trialists and subjects were blinded to treatment allocation. Primary end point was proportion of subjects achieving RBC-transfusion independence within 6 months. One hundred and fifty-two subjects received pomalidomide and 77 placebo. Response rates were 16% (95% confidence interval (CI), 11, 23%) vs 16% (8, 26%; P=0.87). Response in the pomalidomide cohort was associated with ⩽4 U RBC/28 days (odds ratio (OR)=3.1; 0.9, 11.1), age ⩽65 (OR=2.3; 0.9, 5.5) and type of MPN-associated myelofibrosis (OR=2.6; 0.7, 9.5). Responses in the placebo cohort were associated with ⩽4 U RBC/28 days (OR=8.6; 0.9, 82.3), white blood cell at randomization >25 × 109/l (OR=4.9; 0.8, 28.9) and interval from diagnosis to randomization >2 years (OR=4.9; 1.1, 21.9). Pomalidomide was associated with increased rates of oedema and neutropenia but these adverse effects were manageable. Pomalidomide and placebo had similar RBC-transfusion-independence response rates in persons with MPN-associated RBC-transfusion dependence.

Latin America: the next region for haematopoietic transplant progress.

Haematopoietic cell transplant activity in the 28 countries comprising Latin America is poorly defined. We conducted a voluntary survey of members of the Latin American Bone Marrow Transplantation Group regarding transplant activity 2009-2012. Collated responses were compared with data of transplant rates from the Worldwide Network for Blood and Marrow Transplantation for other geographic regions. Several socio-economic variables were analysed to determine correlations with transplant rates. In total, 94 teams from 12 countries reported 11 519 transplants including 7033 autotransplants and 4486 allotransplants. Annual activity increased from 2517 transplants in 2009 to 3263 in 2012, a 30% increase. Median transplants rate (transplant per million inhabitants) in 2012 was 64 (autotransplants, median 40; allotransplants, median 24). This rate is substantially lower than that in North America and European regions (482 and 378) but higher than that in the Eastern Mediterranean and Asia Pacific regions (30 and 45). However, the Latin America transplant rate is 5-8-fold lower than that in America and Europe, suggesting a need to increase transplant availability. Transplant team density in Latin America (teams per million population; 1.8) is 3-4-fold lower than that in North America (6.2) or Europe (7.6). Within Latin America, there is substantial diversity in transplant rates by country partially explained by diverse socio-economic variables including per capita gross national income, health expenditure and physician density. These data should help inform future health-care policy in Latin America.

Autologous hematopoietic cell transplantation for multiple myeloma patients with renal insufficiency: a center for international blood and marrow transplant research analysis.

Autologous hematopoietic cell transplantation (AHCT) in multiple myeloma (MM) patients with renal insufficiency (RI) is controversial. Patients who underwent AHCT for MM between 2008 and 2013 were identified (N=1492) and grouped as normal/mild (⩾60 mL/min), N=1240, moderate (30-59), N=185 and severe RI (<30), N=67 based on Modification of Diet in Renal Disease. Multivariate analyses of non-relapse mortality (NRM), relapse, PFS and overall survival (OS) were performed. Of the 67 patients with severe RI, 35 were on dialysis prior to AHCT. Patients received melphalan 200 mg/m2 (Mel 200) in 92% (normal/mild), 75% (moderate) and 33% (severe) RI; remainder received 140 mg/m2 (Mel 140). Thirty four of 35 patients with severe RI achieved post-AHCT dialysis independence. The 5-year PFS for normal, moderate and severe RI was 35 (95% CI, 31-38)%, 40 (31-49)% and 27 (15-40)%, respectively, (P=0.42); 5-year OS for normal, moderate and severe RI was 68 (65-71)%, 68 (60-76)% and 60 (46-74)%, respectively, (P=0.69). With moderate RI, 5-year PFS for high-dose melphalan 140 mg/m2 was 18 (6-35)% and for Mel 200 was 46 (36-57)% (P=0.009). With severe RI, 5-year PFS Mel 140 was 25 (11-41) % and for Mel 200 was 32 (11-58)% (P=0.37). We conclude that AHCT is safe and effective in patients with MM with RI.

Outcomes following autologous hematopoietic stem cell transplant for patients with relapsed Wilms' tumor: a CIBMTR retrospective analysis.

Despite the marked improvement in the overall survival (OS) for patients diagnosed with Wilms' tumor (WT), the outcomes for those who experience relapse have remained disappointing. We describe the outcomes of 253 patients with relapsed WT who received high-dose chemotherapy (HDT) followed by autologous hematopoietic stem cell transplant (HCT) between 1990 and 2013, and were reported to the Center for International Blood and Marrow Transplantation Research. The 5-year estimates for event-free survival (EFS) and OS were 36% (95% confidence interval (CI); 29-43%) and 45% (95 CI; 38-51%), respectively. Relapse of primary disease was the cause of death in 81% of the population. EFS, OS, relapse and transplant-related mortality showed no significant differences when broken down by disease status at transplant, time from diagnosis to transplant, year of transplant or conditioning regimen. Our data suggest that HDT followed by autologous HCT for relapsed WT is well tolerated and outcomes are similar to those reported in the literature. As attempts to conduct a randomized trial comparing maintenance chemotherapy with consolidation versus HDT followed by stem cell transplant have failed, one should balance the potential benefits with the yet unknown long-term risks. As disease recurrence continues to be the most common cause of death, future research should focus on the development of consolidation therapies for those patients achieving complete response to therapy.

GvHD after umbilical cord blood transplantation for acute leukemia: an analysis of risk factors and effect on outcomes.

Using the Center for International Blood and Marrow Transplant Research (CIBMTR) registry, we analyzed 1404 umbilical cord blood transplantation (UCBT) patients (single (<18 years)=810, double (⩾18 years)=594) with acute leukemia to define the incidence of acute GvHD (aGvHD) and chronic GvHD (cGvHD), analyze clinical risk factors and investigate outcomes. After single UCBT, 100-day incidence of grade II-IV aGvHD was 39% (95% confidence interval (CI), 36-43%), grade III-IV aGvHD was 18% (95% CI, 15-20%) and 1-year cGvHD was 27% (95% CI, 24-30%). After double UCBT, 100-day incidence of grade II-IV aGvHD was 45% (95% CI, 41-49%), grade III-IV aGvHD was 22% (95% CI, 19-26%) and 1-year cGvHD was 26% (95% CI, 22-29%). For single UCBT, multivariate analysis showed that absence of antithymocyte globulin (ATG) was associated with aGvHD, whereas prior aGvHD was associated with cGvHD. For double UCBT, absence of ATG and myeloablative conditioning were associated with aGvHD, whereas prior aGvHD predicted for cGvHD. Grade III-IV aGvHD led to worse survival, whereas cGvHD had no significant effect on disease-free or overall survival. GvHD is prevalent after UCBT with severe aGvHD leading to higher mortality. Future research in UCBT should prioritize prevention of GvHD.