Effect of peptide-binding motif on survival of HLA-haploidentical transplantation with post-transplant cyclophosphamide.

Peptide-binding motif (PBM) model, a hierarchical clustering of HLA class I based on their binding specificity, was developed to predict immunopeptidome divergence. The effect of PBM mismatches on outcomes is unknown in HLA-haploidentical haematopoietic cell transplantation with post-transplant cyclophosphamide (PTCy-haplo). We therefore conducted a retrospective study using national registry data in PTCy-haplo. Overall, 1352 patients were included in the study. PBM-A bidirectional mismatch was associated with an increased risk of overall mortality in multivariable analysis (hazard ratio, 1.26; 95% confidence interval, 1.06 to 1.50; p = 0.010). None of relapse, non-relapse mortality (NRM) and graft-versus-host disease showed significant differences according to PBM-A bidirectional mismatch status in the entire cohort. The impact of PBM-A bidirectional mismatch on overall survival (OS) was preserved within the HLA-A genotype bidirectional mismatch population, and their lower OS stemmed from higher relapse rate in this population. The worse OS due to high NRM with PBM-A bidirectional mismatch was prominent in lymphoid malignancies receiving reduced-intensity conditioning. The PBM model may predict outcomes more accurately than HLA genotype mismatches. In conclusion, this study demonstrated that the presence of PBM-A bidirectional mismatch elevated the risk of mortality of PTCy-haplo. Avoiding PBM-A bidirectional mismatch might achieve better outcomes in PTCy-haplo.

Spacer Length Modification Facilitates Discrimination between Normal and Neoplastic Cells and Provides Clinically Relevant CD37 CAR T Cells.

Despite the remarkable initial efficacy of CD19 chimeric Ag receptor T (CAR-T) cell therapy, a high incidence of relapse has been observed. To further increase treatment efficacy and reduce the rate of escape of Ag-negative cells, we need to develop CAR-T cells that target other Ags. Given its restricted expression pattern, CD37 was considered a preferred novel target for immunotherapy in hematopoietic malignancies. Therefore, we designed a CD37-targeting CAR-T (CD37CAR-T) using the single-chain variable fragment of a humanized anti-CD37 Ab, transmembrane and intracellular domains of CD28, and CD3ζ signaling domains. High levels of CD37 expression were confirmed in B cells from human peripheral blood and bone marrow B cell precursors at late developmental stages; by contrast, more limited expression of CD37 was observed in early precursor B cells. Furthermore, we found that human CD37CAR-T cells with longer spacer lengths exhibited high gene transduction efficacy but reduced capacity to proliferate; this may be due to overactivation and fratricide. Spacer length optimization resulted in a modest transduction efficiency together with robust capacity to proliferate. CD37CAR-T cells with optimized spacer length efficiently targeted various CD37+ human tumor cell lines but had no impact on normal leukocytes both in vitro and in vivo. CD37CAR-T cells effectively eradicated Raji cells in xenograft model. Collectively, these results suggested that spacer-optimized CD37CAR-T cells could target CD37-high neoplastic B cells both in vitro and in vivo, with only limited interactions with their normal leukocyte lineages, thereby providing an additional promising therapeutic intervention for patients with B cell malignancies.

[Cellular kinetics and outcome of tisagenlecleucel for diffuse large B-cell lymphoma].

CD19-targeted chimeric antigen receptor T-cell (CAR-T) therapy has shown promise as treatment of relapsed or refractory B-cell malignancies. However, the clinical utility of early CAR-T monitoring within 1 month after infusion has not been elucidated. In this study, we quantitatively measured CAR-T kinetics in peripheral blood on days 2, 4, 7, 9, 11, 14, 21, and 28 post-infusion using flow cytometry and quantitative polymerase chain reaction in 13 patients with relapsed refractory diffuse large B-cell lymphoma (DLBCL) treated with tisagenlecleucel (tisa-cel). No relationships were identified between bulk CAR-T kinetics and treatment outcomes. Interestingly, the magnitude of CD4+ CAR-T expansion was higher in responders than in nonresponders, while CD8+ CAR-T expansion was minimal in responders. Additionally, CAR-T proliferation was more pronounced in patients with cytokine release syndrome. Our results suggest that CD4+ CAR-T cellular kinetics within 1 month after CAR-T infusion may predict its efficacy after tisa-cel therapy in adult patients with DLBCL.

The new generation tyrosine kinase inhibitor improves the survival of chronic myeloid leukemia patients after allogeneic stem cell transplantation.

The introduction of tyrosine kinase inhibitors (TKIs) in chronic myeloid leukemia (CML) treatment has dramatically improved the prognosis of CML patients and reduced the number of patients receiving allogeneic stem cell transplantation (allo-SCT). However, the impact of the newest-generation TKIs on the overall survival (OS) after allo-SCT has not been well described. To investigate the beneficial effects of TKIs on the prognosis after allo-SCT, we conducted a retrospective observational study using the Transplant Registry Unified Management Program database in Japan. We analyzed 1188 patients (male/female: 738/450; median age: 44 years; range: 16-75) who underwent their first allo-SCT between January 2001 and December 2018. We divided the patients into two groups according to the TKI treatment used before allo-SCT: group 1 was treated with the first generation TKI imatinib; group 2 was treated with the second generation TKIs nilotinib, dasatinib, or bosutinib and/or the third generation TKI ponatinib. We compared the post allo-SCT OS between the two groups. The 3-year OS rates (95%CI) of groups 1 and 2 were 59.3% (54.8%-63.5%) and 65.8% (61.6%-69.6%), respectively (p = 0.017). Multivariate analysis confirmed that group 2 had superior OS after allo-SCT compared to group 1 (p = 0.002). Other factors associated with superior prognosis were age ≤65, performance status (PS) 0/1, a 6/6 HLA-matched donor and chronic-phase (CP) disease status at allo-SCT. A subgroup analysis showed poor prognoses for patients who could not obtain a molecular response before allo-SCT and patients with positive T315I mutation in the BCR/ABL gene. In group 2, early allo-SCT was correlated with superior OS in patients with a blast-crisis disease status at allo-SCT (p = 0.001). The cumulative incidence of non-relapse mortality rate significantly decreased in group 2 (p = 0.0005). The post allo-SCT OS was improved both by pre- and post-management of allo-SCT and by the introduction of newer TKIs.

Prognostic impact of complex karyotype on post-transplant outcomes of myelofibrosis.

Chromosomal abnormalities in the role of prognostic factor for transplant patients with myelofibrosis (MF) are not fully investigated. Regarding complex karyotype (CK), we retrospectively analyzed 241 patients with primary and secondary MF who received a first allogeneic hematopoietic cell transplantation (HCT). Based on an unfavorable karyotype in the Dynamic International Prognostic Scoring System, we compared the outcomes in 3 groups: favorable karyotype, unfavorable karyotype including CK (unfavorable-CK(+)), and unfavorable karyotype not including CK (unfavorable-CK(-)). Overall survival was significantly shorter in the unfavorable-CK(+) group (hazard ratio (HR) 2.49, 95% CI: 1.46-4.24, P < 0.001), whereas there was no difference between the unfavorable-CK(-) group and the favorable group (HR 0.57, 95% CI: 0.20-1.59, P = 0.28). In addition, a significantly higher proportion of patients in the unfavorable-CK(+) group did not achieve complete remission after HCT (P = 0.007). The cumulative incidence of disease progression was significantly higher in the unfavorable-CK(+) group (HR 2.5, 95% CI 1.6-3.92, P < 0.001), whereas that in the unfavorable-CK(-) group was comparable to that in the favorable group (HR 0.49, 95% CI 0.12-1.94, P = 0.31). Further investigations will be needed to clarify the impact of CK on transplant outcomes in MF.

Total body irradiation-containing conditioning regimens without antithymocyte globulin in adults with aplastic anemia undergoing umbilical cord blood transplantation.

Thus far, there have been no large cohort studies on total body irradiation (TBI)-containing conditioning regimens without antithymocyte globulin (ATG) in adults with aplastic anemia (AA) undergoing umbilical cord blood (UCB) transplantation (UCBT). We retrospectively analyzed 115 adults with idiopathic AA undergoing UCBT using TBI-containing reduced-intensity conditioning (RIC) regimens without ATG between 2000 and 2018 on behalf of the Adult Aplastic Anemia Working Group of the Japanese Society for Hematopoietic Cell Transplantation. We then compared transplantation outcomes between a fludarabine (Flu)- and melphalan (Mel)-based regimen (FM) and a Flu- and cyclophosphamide (Cy)-based regimen (FC). The median patient age at UCBT was 41 years. The median total nucleated cell and total CD34+ cell doses in a UCB unit at cryopreservation were 2.5 × 107/kg and 0.7 × 105/kg, respectively. The median follow-up period for survivors was 47 months. The cumulative incidence rate of neutrophil engraftment was 76.5%, and the 4-year overall survival (OS) rate was 64.3%. In multivariate analysis, the covariates that were significantly associated with a higher neutrophil engraftment were total CD34+ cell dose in an UCB unit (≥ 0.7 × 105/kg; hazard ratio, 0.57, P = 0.01) and total dose of TBI (4 Gy of TBI; hazard ratio, 0.32, P = 0.01). There was no significant difference in the cumulative incidence of neutrophil engraftment and the 4-year OS between the FM and FC groups. In conclusion, TBI-containing RIC regimens without ATG are suitable for adults with AA undergoing UCBT. There were no significant differences in transplantation outcomes between the FM and FC groups.

Composite CD79A/CD40 co-stimulatory endodomain enhances CD19CAR-T cell proliferation and survival.

Adoptively transferred CD19 chimeric antigen receptor (CAR) T cells have led to impressive clinical outcomes in B cell malignancies. Beyond induction of remission, the persistence of CAR-T cells is required to prevent relapse and provide long-term disease control. To improve CAR-T cell function and persistence, we developed a composite co-stimulatory domain of a B cell signaling moiety, CD79A/CD40, to induce a nuclear translocating signal, NF-κB, to synergize with other T cell signals and improve CAR-T cell function. CD79A/CD40 incorporating CD19CAR-T cells (CD19.79a.40z) exhibited higher NF-κB and p38 activity upon CD19 antigen exposure compared with the CD28 or 4-1BB incorporating CD19CAR-T cells (CD19.28z and CD19.BBz). Notably, we found that CD19.79a.40z CAR-T cells continued to suppress CD19+ target cells throughout the co-culture assay, whereas a tendency for tumor growth was observed with CD19.28z CAR-T cells. Moreover, CD19.79a.40z CAR-T cells exhibited robust T cell proliferation after culturing with CD19+ target cells, regardless of exogenous interleukin-2. In terms of in vivo efficiency, CD19.79a.40z demonstrated superior anti-tumor activity and in vivo CAR-T cell proliferation compared with CD19.28z and CD19.BBz CD19CAR-T cells in Raji-inoculated mice. Our data demonstrate that the CD79A/CD40 co-stimulatory domain endows CAR-T cells with enhanced proliferative capacity and improved anti-tumor efficacy in a murine model.

Effect of Cytomegalovirus Reactivation With or Without Acute Graft-Versus-Host Disease on the Risk of Nonrelapse Mortality.

BACKGROUND: Despite a strong association between acute graft-versus-host disease (GVHD) and cytomegalovirus reactivation (CMVR), the joint effect of acute GVHD and CMVR on nonrelapse mortality (NRM) has not been well studied. METHODS: We evaluated the impact of CMVR on NRM stratified according to the development of acute GVHD using a landmark method. This study included 6078 patients who received their first allogeneic hematopoietic cell transplantation (HCT) with a preemptive strategy for CMVR between 2008 and 2017. RESULTS: The cumulative incidences of grade 2-4 acute GVHD (G24GVHD), CMVR by day 100, and CMV disease by day 365 were 37.3%, 52.1%, and 2.9%, respectively. Patients with G24GVHD were associated with the subsequent development of CMVR, and the presence of CMVR also increased the risk of G24GVHD. In a landmark analysis at day 65, the cumulative incidence of NRM at 1 year was 5.4%, 10.0%, 13.9%, and 19.7% in patients with G24GVHD-/CMVR-, G24GVHD-/CMVR+, G24GVHD+/CMVR-, and G24GVHD+/CMVR+, respectively. In a multivariate analysis, CMVR was respectively associated with an increased risk of NRM by day 365 in patients without G24GVHD (hazard ratio [HR], 1.59; 95% confidence interval [CI], 1.24-2.05; P < .001) and with G24GVHD (HR, 1.34; 95% CI, 1.06-1.70; P = .014), but the interaction between G24GVHD and CMVR was not significant (P = .326). Subgroup analyses suggested that the joint effect of acute GVHD and CMVR might vary according to the baseline characteristics. CONCLUSIONS: These data regarding the close relationship between acute GVHD and CMVR should provide important implications for the treatment strategy after HCT.

A multicenter phase II study of intrabone single-unit cord blood transplantation without antithymocyte globulin.

To overcome the delayed or failed engraftment after unrelated cord blood transplantation (CBT), we conducted a multicenter phase II study of intrabone single-unit CBT without antithymocyte globulin (ATG) for adult patients with hematological malignancies (UMIN-CTR, UMIN000020997). Sixty-four patients received an intrabone injection of unwashed (n = 61) or washed (n = 3) cord blood after local anesthesia. All injection-related adverse events were mild and resolved spontaneously. Sixty-two patients were evaluable for the efficacy of intrabone CBT of serological HLA-A, -B, and -DR ≥ 4/6 matched cord blood with a median number of 2.57 × 107/kg cryopreserved total nucleated cells. The probability of survival with neutrophil engraftment on day 28 was 77.4% (95% confidence interval, 67.0-85.8%), which exceeded the threshold value. The cumulative incidences of neutrophils ≥ 0.5 × 109/L on day 60 was 80.6% (68.2-88.6%), with a median time to recovery of 21 days after transplantation. The cumulative incidences of platelets ≥ 20 × 109/L and platelets ≥ 50 × 109/L on day 100 were 75.8% (62.6-84.9%) and 72.6% (59.4-82.1%), respectively, with median time to platelets ≥ 20 × 109/L and platelets ≥ 50 × 109/L of 38 and 45 days after transplantation, respectively. The cumulative incidences of grade II-IV and III-IV acute graft-versus-host disease were 29.0% and 6.5%, respectively. All responded to steroid therapy, and secondary treatments were not required. The present study suggests the efficacy of intrabone single-unit CBT without ATG in terms of early engraftment and controllable acute graft-versus-host disease.

Examination of the Relationship and Dissociation Between Minimum Minute Ventilation/Carbon Dioxide Production and Minute Ventilation vs. Carbon Dioxide Production Slope.

BACKGROUND: Minute ventilation/carbon dioxide production (V̇E/V̇CO2) is a variable of cardiopulmonary exercise testing (CPET), which is evaluated by arterial CO2pressure and ventilation-perfusion mismatch via invasive methods. This study evaluated substitute non-invasively obtained variables for minimum V̇E/V̇CO2(Min) and V̇E vs. V̇CO2slope (Slope) and the relationship between Min and Slope.Methods and Results:This study enrolled 1,052 patients with heart disease who underwent CPET and impedance cardiography simultaneously. At first, the correlations between the end-tidal CO2pressure (PETCO2), tidal volume/respiratory rate (TV/RR) ratio, V̇E and V̇CO2Y-intercept (Y-int), and cardiac index (CI) and the Min and Slope were investigated. Second, the correlation between Min and Slope was investigated. PETCO2showed the largest correlation value among the 4 variables. These 4 variables could reveal 84.2% and 81.9% of Min and Slope, respectively. Although Slope correlated with Min (R=0.868) and predicted 78.9% of Min, considering these 4 variables, Slope+Y-int was more strongly correlated with Min (R=0.940); the Slope+Y-int revealed 90.6% of the Min relationship in the multiple regression analysis. CONCLUSIONS: Over 80% of the Min and Slope values were revealed with the above-mentioned 4 variables collected non-invasively. The formula, Min∝Slope+Y-int, can reveal >90% of the Min/Slope relationships, and the Y-int may be a crucial factor to clarify the relationship between Min and Slope.

Sodium Restriction Counseling Reduces Cardiac Events in Patients With Heart Failure.

BACKGROUND: Many heart failure (HF) guidelines recommend sodium restriction for patients with HF, but the outcome of sodium restriction counseling (SRC) for HF patients is still unknown. We wanted to clarify whether SRC reduces cardiac events in patients with HF.Methods and Results:Overall, 800 patients (77±12 years) who were hospitalized for HF were enrolled. During HF hospitalization, patients received SRC; patients were required to have a salt intake of <6 g/day. After discharge, death or HF rehospitalization events were investigated. During a mean follow-up of 319±252 days, 83 patients died, and 153 patients were rehospitalized for HF. SRC significantly decreased all-cause death (odds ratio, 0.42; 95% confidence interval [CI], 0.23-0.76; P<0.01), especially cardiac death of hospitalized HF patients after discharge. In the multivariate analysis adjusted for age, sex, SRC, body mass index, hypertension, dyslipidemia, ß-blockers, and mineralocorticoid receptor antagonist intake, cardiac rehabilitation, and the type of HF, SRC remained a significant predictor of death. Kaplan-Meier analysis showed that SRC significantly reduced deaths and the combined outcome of HF rehospitalization and death. In patients with reduced left ventricular ejection fraction, SRC significantly decreased the mortality rate (odds ratio, 0.27; 95% CI, 0.10-0.71; P<0.01). CONCLUSIONS: SRC reduced the mortality rate after discharge of hospitalized HF patients.

Outcome of Allogeneic Hematopoietic Stem Cell Transplantation in Patients with Myelodysplastic/Myeloproliferative Neoplasms-Unclassifiable: A Retrospective Nationwide Study of the Japan Society for Hematopoietic Cell Transplantation.

To date, there are no data focusing on outcomes of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with myelodysplastic/myeloproliferative neoplasms, unclassifiable (MDS/MPN-U). This study aimed to evaluate outcomes and prognostic factors in patients with MDS/MPN-U after allo-HSCT using Japanese nationwide registry data. The primary endpoint was 3-year overall survival (OS); secondary endpoints included the cumulative incidence of relapse and nonrelapse mortality (NRM). We evaluated the prognostic factors for 3-year OS by univariate analysis using the log-rank test. In our cohort of 86 patients with MDS/MPN-U, we found a 3-year OS of 48.5%, cumulative incidence of relapse of 23.7%, and NRM of 26.3%. The 3-year OS was significantly worse in patients age ≥50 years compared with those age <50 years (38.1% versus 65.0%; P = .049) and in patients with disease progression compared with those without disease progression (28.4% versus 57.2%; P = .042). Our results suggest that allo-HSCT may offer a curative option for patients with MDS/MPN-U, and that age and disease status could be important indicators in helping clinicians determine treatment options for these patients.

Impact of Homozygous Conserved Extended HLA Haplotype on Single Cord Blood Transplantation: Lessons for Induced Pluripotent Stem Cell Banking and Transplantation in Allogeneic Settings.

Induced pluripotent stem cells (iPSCs) have been applied to clinical regenerative cell therapy. Recently, an iPSC banking system to collect HLA haplotype (HP) homozygous (homo) cells for iPSC transplantation in allogeneic settings was proposed, and tissue transplantation generated from iPSC through banking has just began. We analyzed 5017 single cord blood transplantation (CBT) pairs with HLA-A, -B, -C, -DRB1 allele typing data and found 39 donor HLA homo donor to patient HLA heterozygous (hetero) pairs. Of note, all 39 HLA homo to hetero pairs engrafted neutrophils, except 1 early death pair, and all 30 assessable pairs engrafted platelets. Acute graft-versus-host disease (GVHD) grades II to IV and grades III to IV occurred in 17 and 3 of 38 assessable pairs, respectively. Competing risk regression analysis revealed a favorable risk of neutrophil engraftment and higher risk of acute GVHD compared with HLA-matched CBTs. Thirty-seven of 39 homo to hetero pairs had conserved extended HLA HPs (HP-1, n = 18; HP-2, n = 8; HP-3, n = 7; HP-4, n = 4; HP-5, n = 1) that were ethnicity-specific, and at least 1 of 2 patient HLA-A, -B, -C, and -DRB1 alleles in each locus were invariably shared with the same donor HP in 35 pairs. These findings confirmed our preliminary results with 6 HLA homo CBTs, and a trend of high incidence of acute GVHD was newly observed. Importantly, they imply the possibility that HLA-homo iPSC transplantation provides favorable engraftment and accordingly imply the merit of banking iPSC with homozygous major conserved extended HLA HPs.

Prospective Phase 2 Study of Umbilical Cord Blood Transplantation in Adult Acute Leukemia and Myelodysplastic Syndrome.

Almost comparable transplantation outcomes have been reported with HLA-matched unrelated donor transplantation (UDT) and cord blood transplantation (CBT). We conducted a prospective phase 2 study to assess the efficacy and safety of single-unit myeloablative CBT in adult leukemia and myelodysplastic syndrome. Because the day 180 survival of UDT was approximately 80%, we determined the alternative hypothesis of expected day 180 survival with a successful engraftment rate of 80% and set the null hypothesis of threshold rate at 65%. Sixty-two patients (median age, 37 years) were registered, including 28 with acute myelogenous leukemia, 25 with acute lymphoblastic leukemia, and 9 with myelodysplastic syndrome. Of 61 eligible patients, 52 were successfully engrafted and survived at day 180 (85%; 95% confidence interval, 74% to 93%). Single-unit CBT was judged to be effective because the null hypothesis was rejected (P < .001). Furthermore, neutrophil engraftment was observed in 57 patients (92%); the incidences of grade II-IV acute and chronic graft-versus-host disease were 30% and 32%, respectively; and the cumulative incidences of nonrelapse mortality and relapse at 2 years were 18% and 13%, respectively. The present study showed favorable survival outcomes with single-unit CBT. Therefore, this method may be considered if a well-HLA-matched UDT cannot be obtained.

Poor Increase in Pulse Pressure During Cardiopulmonary Exercise Testing Predicts Cardiovascular Death of Patients With Heart Failure With Reduced Ejection Fraction.

BACKGROUND: The increase in stroke volume during inotropic stimulation in patients with heart failure with reduced ejection fraction (HFrEF) is called the "pump function reserve." Few studies have reported on the relationship between pump function reserve and HF prognosis. In HFrEF patients who have pump function reserve, stroke volume increases during exercise. Simply put, the pulse pressure change (∆PP) during cardiopulmonary exercise testing (CPX) is closely related to the prognosis of patients with HFrEF. We hypothesized that ∆PP could predict disease severity and cardiovascular death in patients with HFrEF.Methods and Results:A total of 224 patients with HFrEF who underwent symptom-limited maximal CPX between 2012 and 2016 were enrolled. During a median follow-up of 1.5 years, cardiovascular death occurred in 54 participants (24%). Patients who died demonstrated a lower ∆PP between rest and peak exercise (∆PP [peak-rest]) than those who survived (P<0.001). Cox regression analyses revealed that ∆PP, slope of the relationship between minute ventilation and carbon dioxide production, and B-type natriuretic peptide level were independent predictors of cardiovascular death in patients with HFrEF (P=0.001, 0.021, and <0.001, respectively). CONCLUSIONS: ∆PP (peak-rest) can accurately predict cardiovascular death in patients with HFrEF and may be a useful new prognostic indicator in these patients.

Comparison of Outcomes of Allogeneic Transplantation for Primary Myelofibrosis among Hematopoietic Stem Cell Source Groups.

The choice of alternative donor is a major issue in allogeneic hematopoietic stem cell transplantation (HSCT) for patients with primary myelofibrosis (PMF) without an HLA-matched related donor. We conducted this retrospective study using the Japanese national registry data for 224 PMF patients to compare the outcomes of first allogeneic HSCT from HLA-matched related donor bone marrow (Rtd-BM), HLA-matched related donor peripheral blood stem cells (Rtd-PB), HLA-matched unrelated donor bone marrow (UR-BM), unrelated umbilical cord blood (UR-UCB), and other hematopoietic stem cell grafts. Nonrelapse mortality (NRM) rates at 1 year after Rtd-BM, Rtd-PB, UR-BM, UR-UCB, and other transplantations were 16%, 36%, 30%, 41%, and 48%, respectively. Multivariate analysis identified UR-UCB transplantation, other transplantation, frequent RBC transfusion before transplantation, and frequent platelet (PLT) transfusion before transplantation as predictive of higher NRM. Relapse rates at 1 year after Rtd-BM, Rtd-PB, UR-BM, UR-UCB, and other transplantation were 14%, 17%, 11%, 14%, and 15%, respectively. No specific factor was associated with the incidence of relapse. Overall survival (OS) at 1 and 4 years after Rtd-BM, Rtd-PB, UR-BM, UR-UCB, and other transplantation were 81% and 71%, 58% and 52%, 61% and 46%, 48% and 27%, and 48% and 41%, respectively. Multivariate analysis identified older patient age, frequent RBC transfusion before transplantation, and frequent PLT transfusion before transplantation as predictive of lower OS. In conclusion, UR-UCB transplantation, as well as UR-BM transplantation, can be selected for PMF patients without an HLA-identical related donor. However, careful management is required for patients after UR-UCB transplantation because of the high NRM. Further studies including more patients after HLA-haploidentical related donor and HLA-mismatched unrelated donor transplantation would provide more valuable information for patients with PMF when making decisions regarding the choice of alternative donor.

Quantitative Assessment of T Cell Clonotypes in Human Acute Graft-versus-Host Disease Tissues.

Owing to the difficulty in isolating T cells from human biopsy samples, the characteristics of T cells that are infiltratinghuman acute graft-versus-host disease (GVHD) tissues remain largely uninvestigated. In the present study, TCR-ß deep sequencing of various GVHD tissue samples and concurrent peripheral blood obtained from transplant recipients was performed in combination with functional assays of tissue-infiltrating T cell clones. The T cell repertoire was more skewed in GVHD tissues than in the peripheral blood. The frequent clonotypes differed from tissue to tissue in the same patient, and the frequent clonotypes in the same tissue differed from patient to patient. Two T cell clones were successfully isolated from GVHD skin of a patient. In a cytotoxicity assay, both Tcell clones lysed patient peripheral blood mononuclear cells, but not donor-derived Epstein-Barr virus-transformed lymphoblastoid cells. Their clonotypes were identical to the most and second most frequent T cell clonotypes in the original GVHD skin and accounted for almost all of the skin-infiltrating T cells. These results suggest that human acute GVHD may result from only a few different alloreactive cytotoxic T cell clones, which differ from tissue to tissue and from patient to patient. The characterization of T cells infiltrating human GVHD tissues should be further investigated.

Clinical Implications of t(11;14) in Patients with Multiple Myeloma Undergoing Autologous Stem Cell Transplantation.

Conventional cytogenetic analyses and fluorescent in situ hybridization (FISH) are helpful for stratifying patients with multiple myeloma (MM) into high-risk [t(4;14), t(14;16), and/or del 17p] and standard-risk [t(11;14)] categories. However, the prognosis of patients with MM treated with autologous stem cell transplantation (ASCT) stratified according to these categories remains unclear. This retrospective observational study analyzed 97 patients with MM who received a single, planned ASCT after treatment with 200 mg/m2 melphalan between 2001 and 2011. The patients were grouped according to chromosomal abnormality, including t(11;14) (n = 45), t(4;14) (n = 31), del 17p (n = 10), t(11;14) with del 17p (n = 7), and t(4;14) with del 17p (n = 4). Median overall survival (OS) of the t(11;14) group (64.1 months) was not significantly different from that of the t(4;14) group (not reached), but it was significantly longer than that of the del 17p group (23.0 months; P = .002). G-banding revealed that the median OS of the t(11;14) group with additional chromosomal abnormalities (ACAs) (46.2 months) was significantly shorter than that of the t(11;14) group without ACAs (not reached; P = .005) and the t(4;14) group (not reached; P = .010). These findings highlight the importance of G-banding in patients with t(11;14) MM.

Safety and persistence of WT1-specific T-cell receptor gene-transduced lymphocytes in patients with AML and MDS.

Wilms' tumor 1 (WT1) is constantly expressed in leukemic cells of acute leukemia and myelodysplastic syndrome (MDS). A T-cell receptor (TCR) that specifically reacts with WT1 peptide in the context of HLA-A*24:02 has been identified. We conducted a first-in-human trial of TCR-gene transduced T-cell (TCR-T-cell) transfer in patients with refractory acute myeloblastic leukemia (AML) and high-risk MDS to investigate the safety and cell kinetics of the T cells. The WT1-specific TCR-gene was transduced to T cells using a retroviral vector encoding small interfering RNAs for endogenous TCR genes. The T cells were transferred twice with a 4-week interval in a dose-escalating design. After the second transfer, sequential WT1 peptide vaccines were given. Eight patients, divided into 2 dose cohorts, received cell transfer. No adverse events of normal tissue were seen. The TCR-T cells were detected in peripheral blood for 8 weeks at levels proportional to the dose administered, and in 5 patients, they persisted throughout the study period. The persisting cells maintained ex vivo peptide-specific immune reactivity. Two patients showed transient decreases in blast counts in bone marrow, which was associated with recovery of hematopoiesis. Four of 5 patients who had persistent T cells at the end of the study survived more than 12 months. These results suggest WT1-specific TCR-T cells manipulated by ex vivo culture of polyclonal peripheral lymphocytes survived in vivo and retained the capacity to mount an immune reaction to WT1. This trial was registered at www.umin.ac.jp as #UMIN000011519.

HLA discrepancy between graft and host rather than that graft and first donor impact the second transplant outcome.

Second allogeneic hematopoietic stem cell transplantation is a curative treatment option for patients with hematologic malignancies. However, it is unclear whether HLA discrepancy between graft and first donor has an impact on the outcome of second transplantation. We retrospectively analyzed 646 patients receiving second transplantation after an initial HLA mismatched transplantation. With regard to graft-versus-host, the one-allele mismatch (1 mismatch) group (SHR, 1.88; 95%CI: 0.79-4.45; P=0.163) and more than one-allele mismatch group (≥ 2 mismatch) (SHR, 1.84; 95%CI, 0.75-4.51; P=0.182) had higher risks of grade III-IV acute graft-versus-host disease (GvHD) compared to the HLA-matched (0 mismatch) group. In contrast, no difference in risk of acute GvHD was found among the 0, 1, and ≥ 2 mismatch group with respect to graft-versus-first donor. With regard to graft-versus-host, the ≥ 2 mismatch group showed a significantly higher risk of treatment-related mortality (SHR, 1.90; 95%CI, 1.04-3.50; P=0.038) compared to the 0 mismatch group, while the risk of relapse was slightly lower in the ≥ 2 mismatch group (SHR, 068; 95%CI, 0.44-1.06; P=0.086). In contrast, with regard to graft-versus-first donor, there were no significant differences in treatment-related mortality or relapse among the three groups. These findings suggested that HLA discrepancy between graft and host induces transplant-related immunological responses in second transplantation leading to an increase in treatment-related mortality, in contrast, the biological effects of HLA discrepancy between graft and first donor on outcome may be negligible.