Impact of a Low CD34+ Cell Dose on Allogeneic Peripheral Blood Stem Cell Transplantation

Although the CD34⁺ cell dose in allogeneic peripheral blood stem cell transplantation (PBSCT) is considered to be associated with transplantation outcomes, a lower acceptable threshold has not been defined. We retrospectively analyzed 2919 adult patients with hematologic malignancies who underwent related PBSCT in Japan between 2001 and 2014. According to the number of CD34⁺ cells in the graft, we categorized 2494 patients in the standard group (2 to 5 × 10⁶ cells/kg), 377 patient in the low group (1 to 2?×?10⁶ cells/kg), and 48 patients in the very low group (<1?×?10⁶ cells/kg). Compared with the standard group, the low and very low groups showed delayed neutrophil recovery (93.8%, 89.5%, and 78.3%, respectively at day +28; P?<?.001) and platelet recovery (69.3%, 53.0%, and 45.5%, respectively at day +28; P?<?.001). The 2-year overall survival (OS) in the 3 groups was 45.5%, 45.3%, and 29.8%, respectively, with inferior survival in the very low group. However, a higher percentage of high-risk patients may account for the inferior survival in the very low group, and no significant difference in OS was found in a multivariate analysis. There were no differences in relapse, nonrelapse mortality, or the development of graft-versus-host disease among the 3 groups. In conclusion, allogeneic PBSCT with low CD34⁺ cell doses of 1 to 2?×?10⁶ cells/kg gives acceptable results, whereas further investigations are needed to evaluate the effects of lower doses of <1?×?10⁶ cells/kg owing to the smaller number and the higher percentage of patients with adverse prognostic factors in this cohort.     

两阶段法体外诱导人动员外周血CD34~+细胞分化为巨核细胞

本研究提出两阶段法巨核细胞分化模型:首先将人外周血来源CD34+细胞在Cocktail或CC100两种增殖培养液中培养3、4、5或6 d,然后转入含有TPO和SCF的分化培养液中继续培养7、8或9 d。培养结束后通过比较细胞增殖、分化及成熟情况,优化培养条件。结果显示最优的诱导分化条件是,CD34+细胞在Cocktail培养液中扩增3 d后转入分化培养液中继续培养7 d;所获得的CD41+细胞和多倍体细胞数量是起始CD34+细胞的16倍和3倍;该条件下获得的CD41+和多倍体细胞数量显著高于常用的TPO法和TPO+SCF培养法。因此,运用本研究优化的两阶段培养模式能获得比单阶段直接诱导法更多的CD41+细胞和多倍体细胞,为巨核细胞和血小板相关的理论、临床研究提供新的更高效的巨核细胞体外扩增、分化模型。     

Severe Infections after Unrelated Donor Allogeneic Hematopoietic Stem Cell Transplantation in Adults: Comparison of Cord Blood Transplantation with Peripheral Blood and Bone Marrow Transplantation

We evaluated the occurrence of severe infections in 192 consecutive adult recipients of volunteer unrelated donor allogeneic hematopoietic stem cell transplants, with a detailed analysis of severe infections after receipt of cord blood transplants (CBTs; n = 48) or bone marrow transplants (BMTs)/peripheral blood stem cell transplants (PBSCTs; n = 144). At a 3-year median follow-up, CBT recipients had a higher risk of developing any severe infection (85% versus 69% in BMT/PBSCT recipients, P < .01). CBT recipients had a higher incidence of severe bacterial infections before day +100, but at 3 years the risks of these and other infections were similar in the CBT and BMT/PBSCT groups. In addition, the 100-day and 3-year incidences of infection-related mortality (IRM) did not differ between groups (P = .2 and .5, respectively). In multivariate analysis, the most significant risk factor for IRM in all 192 patients was monocytopenia (.2 × 10⁹/L). In CBT recipients, only neutropenia (.2 × 10⁹/L) on day +30 and low nucleated cell dose infusion (<2 × 10⁷/kg) showed a trend for increased IRM (P = .05 in both cases). Stem cell source had no effect on day +100 or 3-year nonrelapse mortality (NRM), cytomegalovirus infection, cytomegalovirus disease (7% versus 6%), or overall survival (36% versus 39%, respectively). The number of mismatches in HLA (A, B, and DRB1) had no effect on any outcome in CBT recipients. In contrast, in the BMT/PBSCT group, the presence of any mismatch by low or high-resolution HLA typing (A, B, C, and DRB1) increased NRM and decreased overall survival (P < .01). IRM was the primary or secondary cause of death in 61% and 59% of CBT and BMT/PBSCT recipients who died, respectively. Our results confirm the relevance of severe infectious complications as source of severe morbidity and NRM after volunteer unrelated donor hematopoietic stem cell transplantation in adults, but suggest that CBT recipients have a similar risk of dying from an infection if an accurate selection of a cord blood unit is done.     

Comparison of Cytokine Expression in Mesenchymal Stem Cells from Human Placenta, Cord Blood, and Bone Marrow

Mesenchymal stem cells (MSCs) are capable of self-renewal and differentiation into lineages of mesenchymal tissues that are currently under investigation for a variety of therapeutic applications. The purpose of this study was to compare cytokine gene expression in MSCs from human placenta, cord blood (CB) and bone marrow (BM). The cytokine expression profiles of MSCs from BM, CB and placenta (amnion, decidua) were compared by proteome profiler array analysis. The cytokines that were expressed differently, in each type of MSC, were analyzed by real-time PCR. We evaluated 36 cytokines. Most types of MSCs had a common expression pattern including MIF (GIF, DER6), IL-8 (CXCL8), Serpin E1 (PAI-1), GROα(CXCL1), and IL-6. MCP-1, however, was expressed in both the MSCs from the BM and the amnion. sICAM-1 was expressed in both the amnion and decidua MSCs. SDF-1 was expressed only in the BM MSCs. Real-time PCR demonstrated the expression of the cytokines in each of the MSCs. The MSCs from bone marrow, placenta (amnion and decidua) and cord blood expressed the cytokines differently. These results suggest that cytokine induction and signal transduction are different in MSCs from different tissues.     

Drugs as a Frequent Cause of Acute Rash in Patients after CD34+-Selected Peripheral Blood Stem Cell Transplantation

Although histopathological differences have been reported between acute graft-versus-host disease (aGVHD) rash and non-aGVHD rash in CD34⁺-selected peripheral blood stem cell transplantation (PBSCT) recipients, skin biopsy alone is usually insufficient to determine rash etiology. As such, distinguishing inflammatory non-aGVHD rashes, such as drug eruptions, from cutaneous aGVHD after CD34⁺-selected PBSCT remains challenging and relies on clinical presentation. This study aimed to identify etiologies of skin rash in the first year after CD34⁺-selected PBSCT and to assess whether laboratory serologic markers, transplant characteristics, and rash morphology and symptomatology aid in differentiation of cutaneous aGVHD rash versus non-aGVHD rash. We conducted a retrospective study of 243 adult patients who underwent CD34⁺-selected PBSCT at Memorial Sloan Kettering Cancer Center between 2008 and 2011. Among this cohort of transplant recipients, only 43 patients (17.7%) developed cutaneous aGVHD. A total of 152 patients (63%) were identified with rash within 1 year after PBSCT. The proportion of patients who experienced peripheral eosinophilia was not different between those with an aGVHD versus non-aGVHD rash (P ≥ .90), nor when stratified by CD34⁺ selection method (Isolex, P = .70; CliniMACS, P≥ .90). The proportion of patients with pruritus was also not different between those with an aGVHD rash versus non-aGVHD rash (P= .20), or when stratified by CD34⁺ selection modality (Isolex, P = .20; CliniMACS, P = .50). The most common cause of non-aGVHD rash among those with a clear etiology was drug (39% of Isolex; 26% of CliniMACS). Single drug culprits were identified in 51% of drug rashes. The most commonly reported offending agents included antibiotics, keratinocyte growth factor, chemotherapy, and recombinant glycosylated human IL-7.     

Incidence of Supraventricular Arrhythmias during Autologous Peripheral Blood Stem Cell Transplantation

Arrhythmias, especially supraventricular arrhythmias, often complicate the clinical course during autologous hematopoietic cell transplantation (AHCT). We wanted to determine the incidence and risk factors for cardiac arrhythmias during AHCT. The study included 983 patients (median age, 58 years [range, 19 to 77]; 61% male) who underwent AHCT between August 2006 and December 2010 at a single institution and for whom all relevant medical records were available for review. AHCT was done for plasma cell disorders in 58% patients and for lymphoma or leukemia in the remaining. Overall, 92 patients (9.4%) developed a supraventricular tachyarrhythmia at a median of 9 days posttransplantation (range, 0 to 18) and with a median duration of less than 1 day (range, <1 to 17 days). Atrial fibrillation was the most common and seen in 71 patients (7%), followed by atrial flutter and supraventricular tachycardia in 12 (1%) and 8 (1%) patients, respectively. In multivariate analysis, age older than 63 years, presence of premature supraventricular complexes or atrioventricular conduction delay on pretransplantation electrocardiogram, and history of any prior arrhythmia increased the risk of arrhythmia. Development of arrhythmia resulted in longer outpatient follow-up after AHCT, with the median follow-up for those developing an arrhythmia of 22 days compared with 19 days for the rest; P < .001. In conclusion, 9% of patients undergoing ASCT developed supraventricular arrhythmias posttransplantation, and this risk was elevated among older patients, those with a prior history of arrhythmias, and those with pretransplantation electrocardiographic abnormalities.     

The Role of the Different CD34 Epitopes in Detection and Positive Selection of CD34+ Bone Marrow and Peripheral Blood Stem Cells

Positive selection of CD34⁺ cells is an attractive approach to reduce tumour cell contamination in bone marrow (BM) and peripheral blood progenitor cell (PBPC) autografts in malignancies not expressing CD34. All current selection methods use monoclonal antibodies (MoAbs) specific for the class I or class II CD34 epitopes, while for detection most investigators use class III MoAbs. Since the distribution of the different CD34 epitopes on haematopoietic progenitors differs, we studied their significance in CD34⁺ selection procedures. Testing MoAbs against class I, II and III CD34 epitopes on normal BM we observed that ± 23% of class III positive cells was class I negative. A higher expression of the class III epitope compared with classes I or II was observed on the KG1 cell line, whereas no differences in binding capability were found. The class III epitope anti-CD34, 561, was compared with the class I epitope anti-CD34, BI-3C5, both coupled to M450 Dynabeads. The yield of CD34⁺ cells obtained with the 561 beads was 1.7% of the mononuclear cells versus 0.95% using the class I epitope, a 1.95-fold increase (1.3–2.7), whereas the purity was similar (96% in both cases). The absolute number of CD34⁺ cells was therefore twofold higher after 561 selection, including cells with a more mature phenotype. In single cell assay comparable numbers of highly proliferative progenitors but higher numbers of differentiated colonies per phenotypic subfraction were measured. In conclusion, M450 beads coated with the 561 anti-class III CD34 epitope are more efficient in isolating CD34⁺ cells from bone marrow, probably due to a broader distribution of the class III epitope.     

Differences in the Kinetics of Histamine Formation and Granulation of Human Basophilic Cells from Bone Marrow, Peripheral Blood, and Cord Blood

Human bone marrow, cord blood, and peripheral blood contain progenitor cells, which during culture mature to histamine-containing basophilic cells. In bone marrow the histamine content per Alcian blue staining basophilic cell was low before culture. Cultivation of BML cells resulted in increased histamine levels in cultures (P less than 0.05), whereas the basophilic cells did not increase significantly. Cell cultures were stimulated with conditioned medium (CM) produced with allergen-stimulated cells from atopics and from the Mo T leukaemic cell line. Cells from cultures stimulated with CM contained less histamine calculated per basophilic cell than did those from unstimulated cultures (P less than 0.05). There was a significant correlation between the numbers of basophilic cells and the histamine content in cells on day 0 prior to cultivation and after 14 days of cultivation (P less than 0.01 and P less than 0.05 respectively). In cord blood there was a correlation between the numbers of basophilic cells and the histamine levels prior to cultivation (P less than 0.05). During cultivation the number of basophilic cells increased five-fold (P less than 0.02), whereas the histamine levels did not increase resulting in a decreased histamine level per basophilic cell (P less than 0.02). In peripheral blood the basophilic cells contained the highest levels of histamine. The numbers of basophilic cells and their content of histamine showed good correlation both before and after unstimulated and stimulated cultivation (P less than 0.01), whereas unstimulated cultures did not show such correlation. The results indicate the presence of different proportions of progenitor cells in bone marrow, cord blood, and peripheral blood, all with different ability to produce histamine and become granulated basophilic cells.     

Stem and Progenitor Cell Expansion in Co-culture of Mobilized CD34 + Cells and Osteopetrotic Mouse Stroma

1 Introduction Culture systems capable of expanding and/or maintaining hematopoietic stem cells will not only facilitate our understanding of stem cell biology, but also broaden clinical applications. Among various in vitro hematopoietic culture systems, co-cultures of marrow or CD34+ cells with an adherent stromal layer that can produce cytokines and extracellular matrix components most effectively supports long-term hematopoiesis ( LTC ), mimicking the bone marrow micro-environment.     

A Biological Pacemaker Restored by Autologous Transplantation of Bone Marrow Mesenchymal Stem Cells

Objective：To restore cardiac autonomic pace function by autologous trans- plantation and committed differentiation of hone marrow mesenchymal stern cells, and explore the technique for the treatment of sick sinus syndrome. Methods ： Mesenchymal stern cells isolated from canine bone marrow were culture-expanded and differentiated in vitro by 5-azacytidine. The models of sick sinus syndrome in canines were established by ablating sinus node with radio-frequency technique. Differentiated mesenchymal stem cells labeled by BrdU were autologously transplanted into sinus node area through direct injection. The effects of autologous transplantation of mesenchymal stern cells on cardiac autonomic pace function in sick sinus syndrome models were evaluated by electrocardiography, pathologic and immunohistochemical staining technique. Results：There was distinct improvement on pace function of sick sinus syndrome animal models while differentiated mesenchymal stem cells were auto-transplanted into sinus node area. Mesenchymal stern cells transplanted in sinus node area were differentiated into similar sinus node cells and endothelial cells in vivo, and established gap junction with native cardiomyocytes. Conclusion ： The committed- induced mesenchymal stern cells transplanted into sinus node area can differentiate into a- nalogous sinus node cells and improve pace function in canine sick sinus syndrome models.     

Impact of Dose-Adjusted Melphalan in Obese Patients Undergoing Autologous Stem Cell Transplantation

Limited guidance exists for dosing melphalan for autologous stem cell transplantation (ASCT) in the obese patient population, because the current literature reports conflicting clinical outcomes between obese and nonobese patients. In 2014, the American Society for Blood and Marrow Transplantation published conditioning chemotherapy dosing guidelines for obese patients and recommended dosing of melphalan using actual body weight (ABW) in the body surface area calculation. The practice at Barnes-Jewish Hospital has consistently been to dose melphalan using adjusted body weight (AdBW), with a 20% correction when a patient weighs ≥120% of his or her ideal body weight (IBW). The purpose of this study was to compare outcomes of melphalan ASCT in patients with multiple myeloma between obese (≥120% IBW) and nonobese (<120% IBW) populations. This retrospective, single-center study included adult patients with multiple myeloma undergoing first ASCT with melphalan conditioning between January 2009 and December 2012. Patient demographic data, transplantation characteristics, and clinical outcomes were collected. The primary outcome was 3-year event-free survival (EFS). Secondary outcomes included response at 100 days post-transplantation, 3-year overall survival, treatment-related mortality (TRM), time to neutrophil engraftment, and hospital length of stay (LOS). To ensure that melphalan dosage adjustment in the obese population did not impact efficacy, the primary outcome was assessed using a noninferiority design, with a predetermined noninferiority margin of 7%. Assuming a 70% 3-year EFS in the nonobese population, a noninferiority margin of 7%, a power of 80%, and an α value of .05, an analysis of 280 patients was required. A total of 270 patients, including 171 (63%) obese patients and 99 (37%) nonobese patients, met our inclusion criteria. Baseline characteristics were well matched between the 2 cohorts, including high-risk cytogenetics, disease severity at diagnosis, and use of maintenance therapy, with the only detectable differences related to weight itself. The 3-year EFS was 41% for the total cohort, with fewer events occurring in the obese cohort compared with the nonobese cohort (51% versus 40%; P?=?.0025). The 95% lower confidence limit established noninferiority. High-risk cytogenetics, disease severity at diagnosis, and therapy response pre- and post-ASCT were all associated with significantly shorter EFS. No between-group differences in TRM, time to engraftment, or hospital LOS were noted. This retrospective, single-center study found that using AdBW to dose melphalan in obese patients was not inferior to the nonobese population in terms of 3-year EFS. This study adds to the limited evidence on melphalan dosing and suggests that transplantation efficacy is not affected by AdBW dosing in obese patients. Further studies are needed to provide additional insight into the pharmacokinetic differences and best dosing practices for obese patients.     

Peripheral Blood Progenitor Cell Mobilization for Autologous and Allogeneic Hematopoietic Cell Transplantation: Guidelines from the American Society for Blood and Marrow Transplantation

Peripheral blood progenitor cell mobilization practices vary significantly among institutions. Effective mobilization regimens include growth factor alone, chemotherapy and growth factor combined, and, more recently, incorporation of plerixafor with either approach. Many institutions have developed algorithms to improve stem cell mobilization success rates and cost-effectiveness. However, an optimal stem cell mobilization regimen has not been defined. Practical guidelines are needed to address important clinical questions, including which growth factor is optimal, what chemotherapy and dose is most effective, and when to initiate leukapheresis. We present recommendations, based on a comprehensive review of the literature, from the American Society of Blood and Marrow Transplantation.