Decreased serum phosphate levels are a useful biomarker to predict occurrence and severity of cytokine release syndrome in chimeric antigen receptor T-cell therapy

サイトカイン放出症候群の発症と重症化を予見する新たな指標 --キメラ抗原受容体T細胞療法における血清リン値が鍵--. 京都大学プレスリリース. 2022-10-19

Serum Reactivity Against Bacterial Pyruvate Dehydrogenase: Increasing the Specificity of Anti-Mitochondrial Antibodies for the Diagnosis of Primary Biliary Cirrhosis

Antimitochondrial antibodies (AMA) are the serum hallmark of primary biliary cirrhosis (PBC). However, AMA-positivity can be found in non-PBC sera when lower dilutions are used, thus raising issues about the specificity and sensitivity of the test. AMA reacts primarily with the lipoylated domains of pyruvate dehydrogenase-E2 (PDC-E2) which is highly conserved across species, including bacteria. We studied 77 serum samples, including 24 from patients with anti-PDC-E2-positive PBC and 53 controls (16 with autoimmune hepatitis (AIH), 10 with primary sclerosing cholangitis (PSC), and 27 healthy individuals) for their reactivities at serial dilutions (1:10, 1:20 and 1:40) against Escherichia coli DH5 alpha lysate overexpressing human PDC-E2 using immunoblotting (IB). A murine anti-human PDC-E2 monoclonal antibody (mAB) was used as control. We further studied positive sera using adsorption with a synthetic E. coli peptide sharing similarity with human PDC-E2. Finally, we verified whether a unique buffer for E. coli preparation could reduce non-specific serum reactivity. Results demonstrated that 100% of anti-PDC-E2-positive PBC and up to 38% of control sera at 1:10 dilution recognized E. coli PDC-E2 at IB while dilution tests indicated that the overall potency of PBC reactivity was 100-fold higher compared to controls. In fact, a subgroup (20-38%) of non-PBC sera were positive at low titers but lost the reactivity when absorbed with the synthetic E. coli peptide. Finally, our unique buffer reduced the reactivity of non-PBC sera as measured by ELISA. In conclusion, we demonstrated that weak cross-reactivity with E. coli PDC-E2 occurs in non-PBC sera at lower dilutions and that such reactivity is not due to AMA-positivity. The use of a specific buffer might avoid the risk of false positive AMA determinations when E. coli-expressed recombinant antigens are used

T-cell counts in peripheral blood at leukapheresis predict responses to subsequent CAR-T cell therapy

CAR-T細胞の「原料の質」が治療効果と相関 --細胞採取時のリンパ球数がCAR-T細胞の体内での増殖と治療効果を予測する--. 京都大学プレスリリース. 2022-11-22.Prediction of responses to chimeric antigen receptor (CAR)-T cell therapies is essential to maximize their therapeutic efficacy for diffuse large B-cell lymphoma (DLBCL). While several tumor-intrinsic risk factors of resistance and/or early relapse have been identified, clinically useful markers that determine potential activity of CAR-T cells have not been fully investigated. T-cell property at the time of leukapheresis may serve as such a marker. Therefore, we evaluated the clinical impact of CD3⁺ cell count in peripheral blood at leukapheresis on clinical outcomes of CAR-T cell therapy. In total, 44 patients with relapsed or refractory (r/r) DLBCL who received tisagenlecleucel at Kyoto University Hospital were included. According to CD3⁺ cell counts, patients were categorized into CD3[LOW] and CD3[HIGH] groups with a threshold of 553/μL, based on receiver operating characteristic curve analysis. 1-year progression-free survival was significantly higher in the CD3[HIGH] group than the CD3[LOW] group (68.3% vs. 17.3%; adjusted hazard ratio [aHR], 0.37; p = 0.042). Overall survival was also superior in the CD3[HIGH] group (aHR, 0.24; p = 0.043). Moreover, higher CD3⁺ cell counts at leukapheresis were associated with significantly higher lymphocyte counts in peripheral blood at day 7 after CAR-T cell infusion (median 860 vs. 420/μL, P = 0.021), suggesting more extensive expansion of infused CAR-T cells in vivo. In conclusion, we demonstrated that the CD3⁺ cell count at leukapheresis predicts both expansion of CAR-T cells after infusion and outcomes of CAR-T cell therapy, and are useful for building comprehensive therapeutic strategies at the time of leukapheresis

Development of a quantitative prediction model for peripheral blood stem cell collection yield in the plerixafor era

BACKGROUND AIMS: Predicting autologous peripheral blood stem cell (PBSC) collection yield before leukapheresis is important for optimizing PBSC mobilization and autologous stem cell transplantation (ASCT) for treating hematological malignancies. Although guidelines for plerixafor usage based on peripheral blood CD34+ (PB-CD34+) cell count are available, their predictive performance in the real world remains unclear. METHODS: This study retrospectively analyzed 55 mobilization procedures for patients with non-Hodgkin lymphoma or multiple myeloma and developed a novel quantitative prediction model for CD34+ cell collection yield that incorporated four clinical parameters available the day before leukapheresis; namely, PB-CD34+ cell count the day before apheresis (day -1 PB-CD34+), number of prior chemotherapy regimens, disease status at apheresis and mobilization protocol. RESULTS: The effects of PB-CD34+ cell counts on CD34+ cell collection yield varied widely per patient characteristics, and plerixafor usage was recommended in patients with poorly controlled disease or those with a history of heavy pre-treatments even with abundant day -1 PB-CD34+ cell count. This model suggested a more proactive use of plerixafor than that recommended by the guidelines for patients with poor pre-collection condition or those with a higher target number of CD34+ cells. Further, the authors analyzed the clinical outcomes of ASCT and found that plerixafor use for stem cell mobilization did not affect short- or long-term outcomes after ASCT. CONCLUSIONS: Although external validations are necessary, the results can be beneficial for establishing more effective and safer mobilization strategies

Intramuscular Adipose Tissue Content Predicts Patient Outcomes after Allogeneic Hematopoietic Stem Cell Transplantation

移植の成功に重要なのは、「質の良い」筋肉 --コンピュータ断層撮影を用いて評価した骨格筋指標での検討--. 京都大学プレスリリース. 2022-07-12.During clinical courses involving allogeneic hematopoietic stem cell transplantation (allo-HSCT), multidisciplinary assessments for patients including physical functions are indispensable, and quantitative skeletal muscle loss is a poor prognostic marker. In addition, deteriorating quality of muscle due to intra-muscle adipose tissue degeneration can be important as well, because many patients are cachexic or sarcopenic before allo-HSCT, although this approach has not been employed yet. Therefore, we conducted a retrospective cohort study to evaluate the quality, as well as quantity of skeletal muscle using computed tomography (CT). Psoas muscle mass index (PMI) and radiographic density (RD) calculated by cross-sectional area and averaged CT values of the psoas major muscle at the umbilical level were used to determine the quantity and quality of muscle, respectively. In total, 186 adult patients, aged 17-68 years (median, 49) were included in this study, and 46 (24.7%) and 49 (26.3%) patients were assigned to the lower PMI and RG groups. Low RD was identified as an independent risk factor for poor overall survival after allo-HSCT (adjusted hazard ratio 2.54, p<0.01), while PMI was not significant. Decreased RD along with reduced 6-min walking distance before transplantation was also significant factor for increased non-relapse mortality (hazard ratio, 2.69, p=0.01). This study is the first to suggest the use of a qualitative skeletal muscle index to serve as a prognostic indicator following allo-HSCT. RD should be included in pre-transplant screening parameters, and approaches that include rehabilitation focused on improving both muscle quality and quantity may improve the prognosis of allo-HSCT

Higher exercise tolerance early after allogeneic hematopoietic stem cell transplantation is the predictive marker for higher probability of later social reintegration

同種造血幹細胞移植後における社会復帰の予測因子を発見 --移植後リハビリテーションがもつ重要性--. 京都大学プレスリリース. 2021-04-09.As the proportion of long-term survivors after allogeneic hematopoietic stem cell transplantation (allo-HSCT) is on the rise, it is essential to consider the significance of quality of life (QOL), including reintegration with society (returning to school or work). This retrospective cohort study aims to illustrate the precise epidemiology of social reintegration later after allo-HSCT and determine its predictive indicators. We enrolled 56 patients, and 40 patients (71%) attained social reintegration at 2 years post-HSCT. Reintegration failure markedly correlated with an inferior performance status and concurrent chronic graft-versus-host disease. In non-reintegrated patients, the physical function at discharge measured by the 6-min walking distance (6MWD) was markedly decreased. On the multivariate risk analyses, sex (female; odds ratio (OR) 0.07; 95% confidence interval (CI) 0.01–0.54; p = 0.01), HCT-CI (≥ 2; OR 0.10; 95% CI 0.01–0.84; p = 0.03), and change in 6MWD (per 5% increase; OR 1.47; 95% CI 1.01–2.13; p = 0.04) were significant predictors of later social reintegration. This study suggests that a multidisciplinary strategy including rehabilitation is essential, especially in patients with poor predictive markers at an early phase, and we should consider suitable rehabilitation programs to prevent a decline in exercise tolerance and improve social reintegration and overall QOL in patients after allo-HSCT

Overcoming minimal residual disease using intensified conditioning with medium-dose etoposide, cyclophosphamide and total body irradiation in allogeneic stem cell transplantation for Philadelphia chromosome-positive acute lymphoblastic leukemia in adults

BACKGROUND AIMS: An intensified conditioning regimen incorporating medium-dose etoposide (VP16) is an option for patients with acute lymphoblastic leukemia (ALL). However, the prognostic impacts of the addition of VP16 to cyclophosphamide (CY) and total body irradiation (TBI) in patients with Philadelphia chromosome-positive (Ph+) ALL with regard to minimal residual disease (MRD) status have not been elucidated. METHODS: The authors retrospectively compared the outcomes of patients with Ph+ ALL who underwent allogeneic transplantation following VP16/CY/TBI (n = 101) and CY/TBI (n = 563). RESULTS: At 4 years, the VP16/CY/TBI group exhibited significantly better disease-free survival (DFS) (72.6% versus 61.7%, P = 0.027) and relapse rate (11.5% versus 21.1%, P = 0.020) and similar non-relapse mortality (16.0% versus 17.2%, P = 0.70). In subgroup analyses, the beneficial effects of the addition of VP16 on DFS were more evident in patients with positive MRD status (71.2% versus 48.4% at 4 years, P = 0.022) than those with negative MRD status (72.8% versus 66.7% at 4 years, P = 0.24). Although MRD positivity was significantly associated with worse DFS in patients who received CY/TBI (48.4% versus 66.7%, P < 0.001), this was not the case in those who received VP16/CY/TBI (71.2% versus 72.8%, P = 0.86). CONCLUSIONS: This study demonstrated the benefits of the addition of VP16 in Ph+ ALL patients, especially those with positive MRD status. VP16/CY/TBI could be a potential strategy to overcome the survival risk of MRD positivity

Personalized prediction of overall survival in patients with AML in non‐complete remission undergoing allo‐HCT

Allogenic hematopoietic stem cell transplantation (allo-HCT) is the standard treatment for acute myeloid leukemia (AML) in non-complete remission (non-CR); however, the prognosis is inconsistent. This study aimed to develop and validate nomograms and a web application to predict the overall survival (OS) of patients with non-CR AML undergoing allo-HCT (cord blood transplantation [CBT], bone marrow transplantation [BMT], and peripheral blood stem cell transplantation [PBSCT]). Data from 3052 patients were analyzed to construct and validate the prognostic models. The common significant prognostic factors among patients undergoing allo-HCT were age, performance status, percentage of peripheral blasts, cytogenetic risk, chemotherapy response, and number of transplantations. The conditioning regimen was a significant prognostic factor only in patients undergoing CBT. Compared with cyclophosphamide/total body irradiation, a conditioning regimen of ≥3 drugs, including fludarabine, with CBT exhibited the lowest hazard ratio for mortality (0.384; 95% CI, 0.266-0.554; p < 0.0001). A conditioning regimen of ≥3 drugs with CBT also showed the best leukemia-free survival among all conditioning regimens. Based on the results of the multivariable analysis, we developed prognostic models showing adequate calibration and discrimination (the c-indices for CBT, BMT, and PBSCT were 0.648, 0.600, and 0.658, respectively). Our prognostic models can help in assessing individual risks and designing future clinical studies. Furthermore, our study indicates the effectiveness of multi-drug conditioning regimens in patients undergoing CBT