Pathway importance by graph convolutional network and Shapley additive explanations in gene expression phenotype of diffuse large B-cell lymphoma.

Deep learning techniques have recently been applied to analyze associations between gene expression data and disease phenotypes. However, there are concerns regarding the black box problem: it is difficult to interpret why the prediction results are obtained using deep learning models from model parameters. New methods have been proposed for interpreting deep learning model predictions but have not been applied to genetics. In this study, we demonstrated that applying SHapley Additive exPlanations (SHAP) to a deep learning model using graph convolutions of genetic pathways can provide pathway-level feature importance for classification prediction of diffuse large B-cell lymphoma (DLBCL) gene expression subtypes. Using Kyoto Encyclopedia of Genes and Genomes pathways, a graph convolutional network (GCN) model was implemented to construct graphs with nodes and edges. DLBCL datasets, including microarray gene expression data and clinical information on subtypes (germinal center B-cell-like type and activated B-cell-like type), were retrieved from the Gene Expression Omnibus to evaluate the model. The GCN model showed an accuracy of 0.914, precision of 0.948, recall of 0.868, and F1 score of 0.906 in analysis of the classification performance for the test datasets. The pathways with high feature importance by SHAP included highly enriched pathways in the gene set enrichment analysis. Moreover, a logistic regression model with explanatory variables of genes in pathways with high feature importance showed good performance in predicting DLBCL subtypes. In conclusion, our GCN model for classifying DLBCL subtypes is useful for interpreting important regulatory pathways that contribute to the prediction.

Comparison of the impact of two post-remission therapy regimens on cardiac events in acute myeloid leukemia patients undergoing allogeneic hematopoietic stem cell transplantation.

High-dose cytarabine (HD-AraC) or anthracycline-containing chemotherapies are used as post-remission therapy for acute myeloid leukemia (AML) patients. However, it remains unclear which regimen would be better as post-remission therapy before allogeneic hematopoietic stem cell transplantation (allo-HSCT). Thus, we compared the incidence of cardiac events and event-free survival (EFS) after allo-HSCT at two Japanese hospitals between HD-AraC and anthracycline-containing post-remission therapy to clarify the safety of post-remission therapy. Of a total of 132 patients, 68 received HD-AraC (HD-AraC group) and 64 received anthracycline-containing chemotherapy (ANT group). HD-AraC was preferentially selected for core-binding factor AML patients (p = 0.008). The median cumulative anthracycline dose was 115.2 mg/m2 in the HD-AraC group and 318.7 mg/m2 in the ANT group (p < 0.0001). Cardiac events were observed in 18 (13.6%) patients during the follow-up period. The 3-year cumulative incidence of cardiac events was 9.1% in the HD-AraC group and 11.0% in the ANT group (p = 0.70). EFS at 3 years after allo-HSCT was 40.9% in the HD-AraC group and 39.6% in the ANT group (p = 0.51). In conclusion, incidence of cardiac events did not differ significantly between post-remission therapy regimens in AML patients who underwent allo-HSCT.

Safety of biliary stent placement followed by definitive chemoradiotherapy in patients with pancreatic cancer with bile duct obstruction.

BACKGROUND: Although patients with malignant bile duct obstruction due to pancreatic cancer are often initially treated with biliary stent placement, concurrent chemoradiotherapy with stents poses a potential risk of increased toxicity. This retrospective study aimed to evaluate the safety of biliary stent placement followed by definitive concurrent chemoradiotherapy in patients with pancreatic cancer. METHODS: Patients with pancreatic cancer who underwent either a plastic stent or a self-expanding metallic stent placement for malignant bile duct obstruction before definitive concurrent chemoradiotherapy were retrospectively reviewed. Radiotherapy was delivered in 1.8 Gy per fraction to a total dose of 50.4 Gy. Gemcitabine, TS-1 plus Gemcitabine, or TS-1 was the concurrent chemotherapy/regimen. The primary endpoint was the rate of biliary stent-related toxicities, defined as biliary bleeding, duodenal perforation, or bile duct perforation. RESULTS: Thirty patients were included. Plastic stents were placed in 23 patients and self-expanding metallic stent in seven patients at the start of irradiation. The median follow-up time was 20 (range, 2-63) months, and 27 patients (90%) completed concurrent chemoradiotherapy. Biliary stent-related toxicity (grade 3 biliary bleeding) was confirmed in one patient (3%) with a plastic stent 9 months after concurrent chemoradiotherapy. The median duration of locoregional control, progression-free survival, and overall survival were 31.1, 7.3, and 10.5 months, respectively. CONCLUSIONS: Stent placement followed by concurrent chemoradiotherapy was not associated with an apparent increase in toxicity and may be an appropriate treatment for patients with locally advanced pancreatic head cancer with bile duct obstruction.

Prospective validation of the L-index reflecting both the intensity and duration of lymphopenia and its detailed evaluation using a lymphocyte subset analysis after allogeneic hematopoietic stem cell transplantation.

We prospectively validated the previously reported L-index, which reflects both the intensity and duration of lymphopenia, and further evaluated it using a lymphocyte subset analysis after allogeneic hematopoietic stem cell transplantation (HSCT) (n = 30). The L-index was defined as the area over the lymphocyte curve during lymphopenia (<700/µl), and calculated from the start of conditioning to day30 (L-index(30)) and day100 (L-index(100)). The lymphocyte subset including CD3, CD4, CD8, CD19 and CD56 was analyzed before and at 14, 21, 28, 42, 56, 70, and 84 days after HSCT. Cytomegalovirus (CMV) antigenemia was detected as >3 cells/2 slides by the C10/11 method in 21 cases (CMV-AG ≥3 group) at a median of 34 days. L-index(30) was significantly higher in the CMV-AG ≥3 group than in the CMV-AG <3 group (median 20,358 vs 17,235, P = .028). Recovery of the CD4+ and CD56+ cell counts between days 14 and 28 after HSCT was impaired in the CMV-AG ≥3 group. Regarding graft-versus-host disease (GVHD), grade II-IV acute GVHD was identified in 14 patients (GVHD group) at a median of 31 days. L-index(30) was significantly lower in the GVHD group (median 19,048 vs 22,256, P = .043). Recovery of CD3+ cells including both CD4+ and CD8+ cells between days 14 and 28 tended to be better in the GVHD group. In conclusion, L-index(30) was significantly associated with CMV reactivation and grade II-IV acute GVHD, but its clinical significance seemed to differ according to the results of a lymphocyte subset analysis.

Comparison of Danaparoid Sodium and Synthetic Protease Inhibitors for the Treatment of Disseminated Intravascular Coagulation Associated with Hematological Malignancies: A Retrospective Analysis.

BACKGROUND: Danaparoid sodium and synthetic protease inhibitors (SPIs) have been approved for the treatment of disseminated intravascular coagulation (DIC) in Japan. OBJECTIVES: To compare the clinical results of the treatment of DIC with danaparoid or SPIs. METHODS: We retrospectively examined 188 patients with hematological malignancy-related DIC. RESULTS: DIC resolution rate in the danaparoid group was higher than that in the SPIs group (61.5 vs. 42.6%; p = 0.031) on day 7. Multivariate analysis identified the response to chemotherapy as independent predictive factor for DIC resolution on day 7 (odds ratio, OR, 2.28; 95% confidence interval, CI, 1.21-4.31; p = 0.011). While there was no significant difference in the DIC resolution rate on day 14 (75.0 vs. 62.4%; p = 0.117), in a subgroup analysis of patients who did not show an improvement in the underlying disease, the danaparoid group showed a significantly better DIC resolution rate (OR 3.89; 95% CI 1.15-13.2; p = 0.030). There was no difference in the rate of cumulative mortality from bleeding within 28 days between the 2 groups (6.6 vs. 3.3%; p = 0.278). CONCLUSIONS: Danaparoid may be associated with more frequent resolution of DIC in patients with refractory underlying disease.

Surgical resection for persistent localized pulmonary fungal infection prior to allogeneic hematopoietic stem cell transplantation: Analysis of six cases.

OBJECTIVE: Although invasive fungal disease (IFD) is an important complication in allogeneic hematopoietic stem cell transplantation (HSCT), the clinical significance of surgery, including the role of surgical resection for persistent pulmonary fungal disease prior to allogeneic HSCT in the current era with a variety of available antifungal agents, is controversial. We investigated the role of surgical resection. METHODS: We retrospectively investigated six patients who underwent surgical resection of suspected pulmonary fungal disease prior to allogeneic HSCT between April 2007 and June 2016 at our medical center. RESULTS: We present six patients who underwent surgical resection of suspected pulmonary fungal disease prior to allogeneic HSCT. In our case series, three of four patients who were given a presurgical diagnosis of possible IFD were given a proven diagnosis after surgery, including two cases of invasive aspergillosis (IA) and one case of mucormycosis. All surgeries were performed by video-assisted thoracic surgery (VATS) for lobectomy without major complications. Recurrence of IFD was not observed after allogeneic HSCT in any of the six patients. CONCLUSION: Our experience indicated that surgical resection of persistent localized pulmonary lesions of IFD before allogeneic HSCT was helpful for obtaining a definitive diagnosis and might be useful for reducing recurrence after HSCT.

Negative impact of chronic graft-versus-host disease and glucocorticoid on the recovery of physical function after allogeneic hematopoietic stem cell transplantation.

Quality of life of patients who undergo allogeneic hematopoietic stem cell transplantation (HSCT) temporally deteriorates and recovers over several years. We retrospectively evaluate the impact of chronic graft-versus-host disease (GVHD) and glucocorticoid on physical recovery. We included 162 patients who underwent their first allogeneic HSCT between October 2010 and December 2015 in a single hospital. All patients are planned to undergo physical function tests before and 1, 3, 12 months after allogeneic HSCT. Scores of knee extension strength and distance covered in the 6-min walk test (6MWT) recovered at the 12-month assessment. Both chronic GVHD and high dose glucocorticoid were associated with delayed recovery of body mass index (BMI), hand grip strength, knee extension strength, and duration of standing on one foot. Lung GVHD and high dose glucocorticoid had negative impact on the distance covered in the 6MWT. A multivariate analysis revealed that chronic GVHD and glucocorticoid was an independent risk factor for decreased BMI and delayed recovery of muscle strength, respectively. Our results suggest that high-risk patients who have chronic GVHD or who receive glucocorticoid therapy may require reduced dose of glucocorticoid and long-term physical support to recover physical function after transplantation.

Associations between febrile neutropenia-related parameters and the risk of acute GVHD or non-relapse mortality after allogeneic hematopoietic stem cell transplantation.

Infection and inflammation can induce acute graft-vs.-host disease (aGVHD). We hypothesized that febrile neutropenia early after allogeneic hematopoietic cell transplantation (HCT) would increase the risk of aGVHD and non-relapse mortality (NRM). We retrospectively evaluated the impact of fever, C-reactive protein (CRP) concentration and blood stream infection (BSI) early after HCT on the incidence of grade II-IV aGVHD and NRM in 227 patients. Within 7 days after HCT, 91 (40.1%) patients experienced fever for at least 2 days (early-FN group). BSI occurred in 27 (11.9%) patients and the maximum CRP concentration was 2.57 mg/dl in the median. In a multivariate analysis, early-FN (hazard ratio (HR) 1.81, P = 0.007) and older recipient age (HR 1.68, P = 0.019) were significantly associated with the incidence of grade II-IV aGVHD. High-CRP and BSI were not significant risk factors for grade II-IV aGVHD. On the other hand, high-CRP was significantly associated with the incidence of NRM (HR 2.67, P = 0.004) in a multivariate analysis. In conclusion, although fever, CRP elevation and BSI are considered to be closely related events, they had different effects on the incidence of aGVHD and NRM. The development of early-FN after HCT may predict the risk of aGVHD.

Lower glomerular filtration rate predicts increased hepatic and mucosal toxicity in myeloma patients treated with high-dose melphalan.

High-dose melphalan followed by autologous hematopoietic stem cell transplantation (ASCT) is a standard treatment for younger myeloma patients. However, the correlation between its toxicity and renal impairment is not clear. We analyzed this relationship, focusing on estimated glomerular filtration rate (eGFR) as an index of renal function. We evaluated 78 multiple myeloma patients who underwent ASCT following high-dose melphalan at our center. Patients were divided into a higher eGFR group (eGFR ≥ 60) and a lower eGFR group (eGFR < 60). Multivariate analyses revealed that lower eGFR was independently associated with alkaline phosphatase elevation (OR 10.2, P = 0.038), mucositis (OR 10.5, P = 0.032), grade 2-4 co-elevation of both aspartate aminotransferase and alanine aminotransferase (OR 21.3, P = 0.016), delay of reticulocyte engraftment (HR 0.524, P = 0.034), and delay of platelet engraftment (HR 0.535, P = 0.0016). However, lower eGFR was not correlated with overall survival or time-to-next treatment. In summary, renal dysfunction secondary to administration of high-dose melphalan was associated with increased hepatic and mucosal toxicity and delay of hematological recovery, but did not affect survival outcomes.

Outcome of gastrointestinal graft-versus-host disease according to the treatment response.

The optimal treatment strategy for gastrointestinal graft-versus-host disease (GI-GVHD) after allogeneic hematopoietic cell transplantation remains to be established. We retrospectively analyzed 68 cases of GI-GVHD at our institution between 2007 and 2017. The survival outcomes were significantly inferior in patients who did not respond to the first-line treatment (1-year overall survival 27.3 vs 69.2%, P = 0.0017; non-relapse mortality 50.0 vs 18.6%, P = 0.026). After subsequent treatments, 18 patients were refractory to all steroid-based treatments such as steroid pulse therapy and oral beclomethasone dipropionate (BDP). However, these steroid-refractory cases showed a gradual increase in the response rate after the initial diagnosis of steroid refractoriness. This result may be explained by the problem of evaluating the response based solely on the volume of diarrhea, i.e., severe mucosal damage due to refractory GI-GVHD may require a long recovery and sometimes be complicated with other diseases. In conclusion, patients with GI-GVHD who failed to respond to the first-line treatment had inferior survival. However, later improvement may be observed without additional immunosuppressant other than steroid among patients who initially do not respond to steroid therapy. It is important to repeat colonoscopy in patients with refractory GI-GVHD to monitor the activity of GVHD.

Association between Activated Partial Thromboplastin Time and the Amount of Infused Heparin at Bone Marrow Transplantation.

The actual heparin concentration of harvested allogeneic bone marrow varies among harvest centers. We monitor the activated partial thromboplastin time (APTT) of the patient during bone marrow infusion and administer prophylactic protamine according to the APTT. We retrospectively reviewed the charts of consecutive patients who underwent bone marrow transplantation without bone marrow processing at our center between April 2007 and March 2016 (n = 94). APTT was monitored during marrow transfusion in 52 patients. We analyzed the relationship between the APTT ratio and several parameters related to heparin administration. As a result, the weight-based heparin administration rate (U/kg/hour) seemed to be more closely related to the APTT ratio (r = .38, P = .005) than to the total amount of heparin. There was no significant correlation between the APTT ratio and renal or liver function. Bleeding complications during and early after infusion were seen in 3 of 52 patients, and included intracranial, nasal, and punctured-skin bleeding. The APTT ratio during transfusion was over 5.88 in the former 2 patients and 2.14 in the latter. All of these patients recovered without sequelae. In conclusion, slow bone marrow infusion is recommended to decrease the weight-based heparin administration rate when the heparin concentration per patient body weight is high.

Refractory Graft-Versus-Host Disease-Free, Relapse-Free Survival as an Accurate and Easy-to-Calculate Endpoint to Assess the Long-Term Transplant Success.

The aim of this study was to develop a new composite endpoint that accurately reflects the long-term success of allogeneic hematopoietic stem cell transplantation (allo-HSCT), as the conventional graft-versus-host disease (GVHD)-free, relapse-free survival (GRFS) overestimates the impact of GVHD. First, we validated current GRFS (cGRFS), which recently was proposed as a more accurate endpoint of long-term transplant success. cGRFS was defined as survival without disease relapse/progression or active chronic GVHD at a given time after allo-HSCT, calculated using 2 distinct methods: a linear combination of a Kaplan-Meier estimates approach and a multistate modelling approach. Next, we developed a new composite endpoint, refractory GRFS (rGRFS). rGRFS was calculated similarly to conventional GRFS treating grade III to IV acute GVHD, chronic GVHD requiring systemic treatment, and disease relapse/progression as events, except that GVHD that resolved and did not require systemic treatment at the last evaluation was excluded as an event in rGRFS. The 2 cGRFS curves obtained using 2 different approaches were superimposed and both were superior to that of conventional GRFS, reflecting the proportion of patients with resolved chronic GVHD. Finally, the curves of cGRFS and rGRFS overlapped after the first 2 years of post-transplant follow-up. These results suggest that cGRFS and rGRFS more accurately reflect transplant success than conventional GRFS. Especially, rGRFS can be more easily calculated than cGRFS and analyzed with widely used statistical approaches, whereas cGRFS more accurately represents the burden of GVHD-related morbidity in the first 2 years after transplantation.

Delayed platelet recovery after allogeneic hematopoietic stem cell transplantation: Association with chronic graft-versus-host disease and survival outcome.

Delayed platelet recovery (DPR) despite prompt neutrophil engraftment is frequently observed after allogeneic hematopoietic stem cell transplantation (HSCT). However, few studies have evaluated the risk factors and long-term outcome. Therefore, we retrospectively analysed 219 adult patients who underwent their first allogenic HSCT with neutrophil engraftment. Of these 219 patients, 50 (22.8%) had DPR that was defined as relapse-free survival at day 60 after HSCT without primary platelet recovery despite neutrophil engraftment. The results of a multivariate analysis showed that a high-risk underlying disease (odds ratio [OR], 2.38; 95% confidence interval [CI], 1.04-5.48; P = .041) and human leukocyte antigen-mismatched HSCT (OR, 2.63; 95% CI, 1.28-5.43; P = .009) were associated with an increased risk of DPR. In univariate analyses, the occurrence of DPR was significantly associated with inferior overall survival, high nonrelapse mortality, and a low incidence of chronic graft-versus-host disease (GVHD), despite a comparable relapse rate. In multivariate analyses, DPR was associated with inferior overall survival (hazard ratio [HR], 2.00; 95% CI, 1.23-3.27; P = .005) and a low incidence of chronic GVHD (HR, 0.42; 95% CI, 0.22-0.78; P = .002). In conclusion, DPR was a strong predictor of shorter survival but also less frequent chronic GVHD.

Safety of avoiding systemic corticosteroid administration for grade II acute graft-versus-host disease limited to the skin.

We hypothesized that systemic corticosteroid administration would be safely avoided not only in grade I acute graft-versus-host disease (GVHD) but also in selected patients with grade II acute GVHD limited to the skin (grade IIs GVHD). We retrospectively evaluated risk factors for subsequent GVHD progression, defined as the involvement of other organs or progression to grade III to IV GVHD, in 50 patients with acute GVHD of grade IIs at its onset. Sixteen patients received systemic corticosteroid administration before GVHD progression. The cumulative incidence of GVHD progression at 28 days from the onset of grade IIs GVHD was 24%. Twenty-five patients did not require systemic corticosteroid administration throughout the entire episode of acute GVHD. Systemic corticosteroid administration before GVHD progression did not affect GVHD progression, chronic GVHD, or non-relapse mortality. Early onset (less than 26 days from transplantation) of grade IIs GVHD was identified as the only statistically significant risk factor for GVHD progression (hazard ratio 6.73, 95% confidence interval 1.5-31.1, P = 0.01). In conclusion, avoiding systemic corticosteroid administration for selected patients with grade IIs GVHD before GVHD progression did not compromise the transplantation outcomes. Patients with early-onset grade IIs GVHD were at high risk for GVHD progression.

Antifungal prophylaxis with fluconazole in allogeneic stem cell transplantation recipients who had prior invasive aspergillosis with subsequent complete resolution by computed tomography.

BACKGROUND: Consensus has yet to be reached regarding secondary prophylaxis in allogeneic hematopoietic stem cell transplantation (HSCT) with a complete resolution of invasive aspergillosis (IA) confirmed by chest computed tomography (CT). METHODS: We retrospectively evaluated the feasibility of antifungal prophylaxis with fluconazole in allogeneic HSCT recipients who had previously developed IA which showed complete resolution as confirmed by chest CT before HSCT. Consecutive adult patients who underwent allogeneic HSCT at our institution and who had received fluconazole as systemic antifungal prophylaxis from June 2007 to January 2015 were included. We compared the clinical outcomes between patients with a past history of IA who showed a complete resolution of chest CT abnormalities (n = 13) and those without a previous history of IA (n = 137). RESULTS: The cumulative incidence of proven or probable IA was 8.8% in the group without a past history of IA and 0.0% in the group with a past history of IA (p = .268). The cumulative incidence of proven or probable invasive fungal disease (IFD) within 100 days after allogeneic HSCT was 10.9% in the group without a past history of IA and 15.4% in the group with a past history of IA (p = .647). Fluconazole was switched to anti-mould agents in two-thirds of the patients in each group by day 100 after HSCT. CONCLUSIONS: Fluconazole was confirmed to be an acceptable prophylactic agent early after allogeneic HSCT in appropriately selected patients.

Pseudo-autologous stem cell transplantation for donor-derived mantle cell lymphoma 12 years after allogeneic transplantation.

Donor-derived malignancy is a rare morbidity after allogeneic hematopoietic stem cell transplantation (HSCT), in which most previous cases have presented as acute leukemia or myelodysplastic syndrome. There have, however, been very few reports of donor-derived lymphoma. Here, we present a case of donor-derived mantle cell lymphoma 12 years after allogeneic HSCT, which was successfully treated with chemotherapy followed by pseudo-autologous HSCT (pASCT), i.e., an autologous HSC transplant following allogeneic HSCT in which the infused stem cell is considered to be derived from the donor cells. Although pASCT carries the risk of graft-versus-host disease (GVHD) due to the reinfusion of donor-derived peripheral blood cells, the present case did not develop GVHD without prophylaxis. The current case and a small number of previous reports suggest that the duration between allogeneic HSCT and pASCT may be important to the induction of immune tolerance, but further study in a larger number of cases is needed.

A Unique T-Cell Receptor Amino Acid Sequence Selected by Human T-Cell Lymphotropic Virus Type 1 Tax301-309-Specific Cytotoxic T Cells in HLA-A24:02-Positive Asymptomatic Carriers and Adult T-Cell Leukemia/Lymphoma Patients.

We previously reported that the T-cell receptor (TCR) repertoire of human T-cell lymphotropic virus type 1 (HTLV-1) Tax301-309-specific CD8+ cytotoxic T cells (Tax301-309-CTLs) was highly restricted and a particular amino acid sequence motif, the PDR motif, was conserved among HLA-A*24:02-positive (HLA-A*24:02+) adult T-cell leukemia/lymphoma (ATL) patients who had undergone allogeneic hematopoietic cell transplantation (allo-HSCT). Furthermore, we found that donor-derived PDR+ CTLs selectively expanded in ATL long-term HSCT survivors with strong CTL activity against HTLV-1. On the other hand, the TCR repertoires in Tax301-309-CTLs of asymptomatic HTLV-1 carriers (ACs) remain unclear. In this study, we directly identified the DNA sequence of complementarity-determining region 3 (CDR3) of the TCR-ß chain of Tax301-309-CTLs at the single-cell level and compared not only the TCR repertoires but also the frequencies and phenotypes of Tax301-309-CTLs between ACs and ATL patients. We did not observe any essential difference in the frequencies of Tax301-309-CTLs between ACs and ATL patients. In the single-cell TCR repertoire analysis of Tax301-309-CTLs, 1,458 Tax301-309-CTLs and 140 clones were identified in this cohort. Tax301-309-CTLs showed highly restricted TCR repertoires with a strongly biased usage of BV7, and PDR, the unique motif in TCR-ß CDR3, was exclusively observed in all ACs and ATL patients. However, there was no correlation between PDR+ CTL frequencies and HTLV-1 proviral load (PVL). In conclusion, we have identified, for the first time, a unique amino acid sequence, PDR, as a public TCR-CDR3 motif against Tax in HLA-A*24:02+ HTLV-1-infected individuals. Further investigations are warranted to elucidate the role of the PDR+ CTL response in the progression from carrier state to ATL.IMPORTANCE ATL is an aggressive T-cell malignancy caused by HTLV-1 infection. The HTLV-1 regulatory protein Tax aggressively promotes the proliferation of HTLV-1-infected lymphocytes and is also a major target antigen for CD8+ CTLs. In our previous evaluation of Tax301-309-CTLs, we found that a unique amino acid sequence motif, PDR, in CDR3 of the TCR-ß chain of Tax301-309-CTLs was conserved among ATL patients after allo-HSCT. Furthermore, the PDR+ Tax301-309-CTL clones selectively expanded and showed strong cytotoxic activities against HTLV-1. On the other hand, it remains unclear how Tax301-309-CTL repertoire exists in ACs. In this study, we comprehensively compared Tax-specific TCR repertoires at the single-cell level between ACs and ATL patients. Tax301-309-CTLs showed highly restricted TCR repertoires with a strongly biased usage of BV7, and PDR, the unique motif in TCR-ß CDR3, was conserved in all ACs and ATL patients, regardless of clinical subtype in HTLV-1 infection.

Positive Cytotoxic Crossmatch Predicts Delayed Neutrophil Engraftment in Allogeneic Hematopoietic Cell Transplantation from HLA-Mismatched Related Donors.

Although a positive cytotoxic crossmatch (XM) has been reported to predict graft failure, mainly in solid organ transplantations, its significance in allogeneic hematopoietic cell transplantation (HCT) remains to be elucidated. We retrospectively assessed the impact of positive XM on neutrophil engraftment in 41 patients who underwent HCT with an HLA-mismatched related donor. XM was positive in 22 patients. Six of these 22 patients were also positive for anti-HLA antibody, whereas only 1 was positive for donor-specific anti-HLA antibody. The cumulative incidence of engraftment at day +28 was 89.5% in patients with negative XM versus 59.1% in those with positive XM (P = .08). In particular, positive B cell warm XM was significantly associated with a lower probability of engraftment at day +28 (46.7% versus 88.5%; P = .04). In a multivariate analysis, both positive XM and positive B cell warm XM were significantly associated with delayed engraftment (hazard ratio [HR], .46; P = .02 and HR, .41; P = .01, respectively). There was no significant difference in the achievement of engraftment between those with and without detection of anti-HLA antibodies. In conclusion, positive XM might be associated with a delayed neutrophil engraftment after HCT from HLA-mismatched related donors.

Clinical significance of repeat blood cultures during febrile neutropenia in adult acute myeloid leukaemia patients undergoing intensive chemotherapy.

BACKGROUND: We evaluated the clinical significance of repeat blood cultures in persistent and recurrent fever during neutropenia in adult acute myeloid leukaemia (AML) and myelodysplastic syndrome (MDS) patients undergoing intensive chemotherapy. METHODS: We retrospectively reviewed the chemotherapy cycles at our centre between January 2007 and December 2015. Blood cultures obtained within three days after initial febrile neutropenia (FN) were defined as initial blood cultures and those obtained on or after day 4 were defined as repeat blood cultures. RESULTS: Overall, 321 chemotherapy cycles in 89 patients were subjected to review. FN was identified in 276 (86.0%) chemotherapy cycles. In persistent FN (134 episodes), the causative pathogens were detected by repeat blood cultures in seven episodes (5.2%), including only three episodes (2.2%) of new infection. Shaking chills and high body temperature were identified as significant predictors for bloodstream infection (BSI). In recurrent FN (85 episodes), the causative pathogens were detected in seven episodes (8.2%), and all of these were new organisms. The frequency of detecting new pathogens by repeat blood cultures in recurrent FN (7/85) was higher than that in persistent FN (3/134) (p = .0491). A history of recent BSI was identified as a significant predictor for BSI in recurrent FN. CONCLUSIONS: The diagnostic yield of repeat blood cultures for persistent FN was low in intensive chemotherapy for AML and MDS. The frequency of repeat blood cultures for persistent FN could be reduced based on predictors. On the other hand, blood cultures were considered to be essential in cases with recurrent FN.

Acyclovir-resistant herpes simplex virus 1 infection early after allogeneic hematopoietic stem cell transplantation with T-cell depletion.

We previously reported that oral low-dose acyclovir (200 mg/day) for the prevention of herpes simplex virus (HSV) infections after allogenic hematopoietic stem cell transplantation (HSCT) is effective without the emergence of acyclovir-resistant HSV infections. However, HSV infections are of significant concern because the number of allogeneic HSCT with T-cell depletion, which is a risk factor of the emergence of drug-resistant HSV infections, has been increasing. We experienced a 25-year-old female who received allogenic HSCT from an unrelated donor with 1-antigen mismatch using anti-thymocyte globulin. Despite acyclovir prophylaxis (200 mg/day), she developed the right palatal ulcer that was positive for HSV-1 specific antigen by fluorescent antibody on day 20 and developed new hypoglossal and tongue ulcers on day 33. Replacement of acyclovir with foscarnet improved her ulcers. We isolated 2 acyclovir-resistant and foscarnet-sensitive strains from the right palatal and hypoglossal ulcers, which had the same frame shift mutation in the thymidine kinase genes. The rate of proliferation of the isolate from the hypoglossal ulcer was faster than that from the right palatal ulcer in the plaque reduction assay. HSV strains that acquired acyclovir-resistant mutations at the right palatal ulcer with larger plaque might spread to the hypoglossal ulcer as the secondary site of infection because of better growth property. Second-line antiviral agents should be considered when we suspect treatment failure of HSV infection, especially in HSCT with T-cell depletion. Further studies are required whether low-dose acyclovir prophylaxis leads to the emergence of virological resistance.