Post-transplant cyclophosphamide, calcineurin inhibitor, and mycophenolate mofetil compared to anti-thymocyte globulin, calcineurin inhibitor, and methotrexate combinations as graft-versus-host disease prophylaxis post allogeneic stem cell transplantation from sibling and unrelated donors in patients with acute myeloid leukemia: a study on behalf of the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation

Post-transplant cyclophosphamide plus calcineurin inhibitor (CNI)(tacrolimus or cyclosporine A) plus mycophenolate mofetil (PTCy/TAC or CSA/MMF) and anti-thymocyte globulin plus CNI (tacrolimus or cyclosporine A) plus methotrexate (ATG/TAC or CSA/MTX) are common graft-versus-host disease (GVHD) prophylaxis regimens. We compared the two regimens in patients with acute myeloid leukemia (AML) undergoing allogeneic transplantation from matched siblings or unrelated donors. 402 received PTCy/TAC or CSA/MMF and 5648 received ATG/TAC or CSA/MTX. Patients in the PTCy-based group were younger (48.7 vs. 51.5 years, p = 0.024) and there was a higher frequency of patient cytomegalovirus seropositivity and female donor to male patient combination in this group (77.8% vs. 71.8%, p = 0.009 and 18.4% vs. 14.4%, p = 0.029, respectively). More patients in the PTCy-based group received reduced-intensity conditioning (51.5% vs. 41%, p < 0.0001). No differences were observed in the incidence of acute GVHD grade II-IV and III-IV (21.2% vs. 20.4%, p = 0.92 and 8.1% vs. 6%, p = 0.1) or 2-year total and extensive chronic GVHD (33.7% vs. 30%, p = 0.09 and 10.7% vs. 11.2%, p = 0.81) between the groups. In the multivariate analysis, all transplant outcomes did not differ between the groups. PTCy/CNI/MMF and ATG/CNI/MTX are alternative regimens for GVHD prophylaxis in AML patients.

Altered serum metabolome as an indicator of paraneoplasia or concomitant cancer in patients with rheumatic disease

OBJECTIVES

A timely diagnosis is imperative for curing cancer. However, in patients with rheumatic musculoskeletal diseases (RMDs) or paraneoplastic syndromes, misleading symptoms frequently delay cancer diagnosis. As metabolic remodelling characterises both cancer and RMD, we analysed if a metabolic signature can indicate paraneoplasia (PN) or reveal concomitant cancer in patients with RMD.

METHODS

Metabolic alterations in the sera of rheumatoid arthritis (RA) patients with (n=56) or without (n=52) a history of invasive cancer were quantified by nuclear magnetic resonance analysis. Metabolites indicative of cancer were determined by multivariable regression analyses. Two independent RA and spondyloarthritis (SpA) cohorts with or without a history of invasive cancer were used for blinded validation. Samples from patients with active cancer or cancer treatment, pulmonary and lymphoid type cancers, paraneoplastic syndromes, non-invasive (NI) precancerous lesions and non-melanoma skin cancer and systemic lupus erythematosus and samples prior to the development of malignancy were used to test the model performance.

RESULTS

Based on the concentrations of acetate, creatine, glycine, formate and the lipid ratio L1/L6, a diagnostic model yielded a high sensitivity and specificity for cancer diagnosis with AUC=0.995 in the model cohort, AUC=0.940 in the blinded RA validation cohort and AUC=0.928 in the mixed RA/SpA cohort. It was equally capable of identifying cancer in patients with PN. The model was insensitive to common demographic or clinical confounders or the presence of NI malignancy like non-melanoma skin cancer.

CONCLUSIONS

This new set of metabolic markers reliably predicts the presence of cancer in arthritis or PN patients with high sensitivity and specificity and has the potential to facilitate a rapid and correct diagnosis of malignancy.

The remission status of AML patients after allo-HCT is associated with a distinct single-cell bone marrow T-cell signature

ABSTRACT

Acute myeloid leukemia (AML) is a hematologic malignancy for which allogeneic hematopoietic cell transplantation (allo-HCT) often remains the only curative therapeutic approach. However, incapability of T cells to recognize and eliminate residual leukemia stem cells might lead to an insufficient graft-versus-leukemia (GVL) effect and relapse. Here, we performed single-cell RNA-sequencing (scRNA-seq) on bone marrow (BM) T lymphocytes and CD34+ cells of 6 patients with AML 100 days after allo-HCT to identify T-cell signatures associated with either imminent relapse (REL) or durable complete remission (CR). We observed a higher frequency of cytotoxic CD8+ effector and gamma delta (γδ) T cells in CR vs REL samples. Pseudotime and gene regulatory network analyses revealed that CR CD8+ T cells were more advanced in maturation and had a stronger cytotoxicity signature, whereas REL samples were characterized by inflammatory tumor necrosis factor/NF-κB signaling and an immunosuppressive milieu. We identified ADGRG1/GPR56 as a surface marker enriched in CR CD8+ T cells and confirmed in a CD33-directed chimeric antigen receptor T cell/AML coculture model that GPR56 becomes upregulated on T cells upon antigen encounter and elimination of AML cells. We show that GPR56 continuously increases at the protein level on CD8+ T cells after allo-HCT and confirm faster interferon gamma (IFN-γ) secretion upon re-exposure to matched, but not unmatched, recipient AML cells in the GPR56+ vs GPR56- CD8+ T-cell fraction. Together, our data provide a single-cell reference map of BM-derived T cells after allo-HCT and propose GPR56 expression dynamics as a surrogate for antigen encounter after allo-HCT.

Endothelial Activation and Stress Index (EASIX) to predict mortality after allogeneic stem cell transplantation: a prospective study

BACKGROUND

We previously reported that the "Endothelial Activation and Stress Index" (EASIX; ((creatinine×lactate dehydrogenase)÷thrombocytes)) measured before start of conditioning predicts mortality after allogeneic hematopoietic stem cell transplantation (alloSCT) when used as continuous score. For broad clinical implementation, a prospectively validated EASIX-pre cut-off is needed that defines a high-risk cohort and is easy to use.

METHOD

In the current study, we first performed a retrospective cohort analysis in n=2022 alloSCT recipients and identified an optimal cut-off for predicting non-relapse mortality (NRM) as EASIX-pre=3. For cut-off validation, we conducted a multicenter prospective study with inclusion of n=317 first alloSCTs from peripheral blood stem cell in adult patients with acute leukemia, lymphoma or myelodysplastic syndrome/myeloproliferative neoplasms in the European Society for Blood and Marrow Transplantation network.

RESULTS

Twenty-three % (n=74) of alloSCT recipients had EASIX-pre ≥3 taken before conditioning. NRM at 2 years was 31.1% in the high EASIX group versus 11.5% in the low EASIX group (p<0.001). Patients with high EASIX-pre also had worse 2 years overall survival (51.6% vs 70.9%; p=0.002). We were able to validate the cut-off and found that EASIX ≥3 was associated with more than twofold increased risk for NRM in multivariate analysis (HR=2.18, 95% CI 1.2 to 3.94; p=0.01). No statistically significant difference could be observed for the incidence of relapse.

CONCLUSIONS

The results of this study provide a prospectively validated standard laboratory biomarker index to estimate the transplant-related mortality risk after alloSCT. EASIX ≥3 taken before conditioning identifies a population of alloSCT recipients who have a more than twofold increased risk of treatment-related mortality.

Prehabilitative high-intensity interval training and resistance exercise in patients prior allogeneic stem cell transplantation

Physical capacity prior allogeneic stem cell transplantation (allo-HCT) has been shown as a relevant prognostic factor for survival after transplant. Therefore, we evaluated feasibility and preliminary efficacy of a high-intensity interval training (HIIT) and moderate to high-intensity resistance exercise (RE) to increase physical capacity in patient's prior allo-HCT. In this multicentre single arm pilot study, a supervised exercise program was performed twice weekly for 4-12 weeks prior allo-HCT, depending on the individual time remaining. Outcomes were feasibility (recruitment, adherence, safety), physical capacity (cardiorespiratory fitness [VO2peak], muscle strength) and patient reported outcomes (physical functioning, fatigue). Thirty patients were intended, 16 could be included, and 14 completed post intervention assessment (75% male, 55 ± 11 years). The study was stopped early due to a low recruitment rate. Nine patients (64%) reached the initial minimum planned number of eight exercise sessions. Individual adherence was high with 92% for HIIT and 85% for RE. 87% of all performed exercise sessions were completed without complaints and VO2peak increased significantly from 20.4 to 23.4 ml/kg/min. The low recruitment rate suggests that initiation of the intervention concept immediately before allo-HCT is feasible only in a small number of patients. In particular, the timeframe directly prior allo-HCT seems too short for exercise interventions, although the exercise program was designed to improve outcomes in a very short time frame. HIIT and RE were feasible, effective and well accepted by the included patients.

Data-driven grading of acute graft-versus-host disease

Despite advances in allogeneic hematopoietic cell transplantation, acute graft-versus-host disease (aGVHD) remains its leading complication, yet with heterogeneous outcomes. Here, we analyzed aGVHD phenotypes and clinical classifications in depth in large, multicenter cohorts involving 3019 patients and addressed prevailing gaps by developing data-driven models. We compared, tested and verified these along with all conventional classifications in independent cohorts and found that data-driven grading outperformed conventional grading in Akaike information criterion and concordance index metrics. Data-driven classifications refined aGVHD assessment with up to 12 severity grades, which were associated with distinct nonrelapse mortality (NRM) and confirmed the key role of intestinal aGVHD. We developed an online calculator for physicians to implement principal component-derived grading (PC1). These results provide substantial insight into the evaluation of aGVHD phenotypes and multiorgan involvement, which relegates the exclusive reporting of overall aGVHD severity grades in transplant registries and clinical trials. Data-driven aGVHD grading provides an expandable platform to refine classification and transplant risk assessment.

EASIX-1year and late mortality after allogeneic stem cell transplantation

Patients with hematological malignancies who survive the first year after allogeneic stem cell transplantation (allo-SCT) without relapse have a substantial risk of nonrelapse mortality (NRM) and missing predictive markers. The Endothelial Activation and Stress Index (EASIX) predicts endothelial complications and NRM early after allo-SCT. We hypothesized that EASIX assessed 1 year after allo-SCT in survivors who were disease free may predict late NRM. Survivors who were relapse-free at 1 year after allo-SCT were retrospectively studied in 2 independent cohorts (training cohort, n = 610; merged validation cohort, n = 852). EASIX determined 1 year after allo-SCT correlated with the overall survival (OS), NRM, and relapse. Serum endothelial and inflammatory markers were measured in the training cohort and correlated with EASIX-1year, which predicted OS and NRM but not relapse risk in both the training and validation cohorts in univariable and multivariable Cox regression analyses. Brier score and c-index analyses validated the univariable EASIX effects. There was no significant interaction between EASIX-1year and incidence of chronic graft-versus-host disease (GVHD) on OS. EASIX-1year predicted the outcome irrespective of preexisting comorbidities. Principal causes of NRM in both training and validation cohorts were infections with and without GVHD as well as cardiovascular complications. EASIX-1year correlated with sCD141 and interleukin-18 but not with C-reactive protein, suppressor of tumorigenicity-2, angiopoietin-2, CXCL9, or CXCL8. To our knowledge, EASIX-1year is the first validated predictor of late overall and NRM. Patients who are high risk as defined by EASIX-1year might be considered for intensified surveillance and prophylactic measures.

IFNγ Causes Keratinocyte Necroptosis in Acute Graft-Versus-Host Disease

Epidermal keratinocytes form the first-line cellular barrier of the skin for protection against external injuries and maintenance of local tissue homeostasis. Expression of ZBP1 was shown to cause necroptotic keratinocyte cell death and skin inflammation in mice. We sought to characterize the relevance of ZBP1 and necroptosis in human keratinocytes and type 1-driven cutaneous acute graft-versus-host disease. in this study, we identify ZBP1 expression, necroptosis, and interface dermatitis as being the hallmarks of acute graft-versus-host disease. ZBP1 expression was dependent on leukocyte-derived IFNγ, and interference with IFNγ signaling by Jak inhibition prevented cell death. In predominantly IL-17-driven psoriasis, both ZBP1 expression and necroptosis could not be detected. Of note, in contrast to the signaling in mice, ZBP1 signaling in human keratinocytes was not affected by RIPK1's presence. These findings show that ZBP1 drives inflammation in IFNγ-dominant type 1 immune responses in human skin and may further point to a general role of ZBP1-mediated necroptosis.

Statin-based endothelial prophylaxis and outcome after allogeneic stem cell transplantation

BACKGROUND

Allogeneic haematopoietic stem cell transplantation (alloSCT) often remains the only curative therapy for hematologic malignancies. Although the management of transplant-associated adverse events considerably improved over the last decades, nonrelapse mortality (NRM) remains a challenge, and endothelial dysfunction was identified as a major contributor to NRM.

METHODS

Statin-based endothelial prophylaxis (SEP) has been implemented in the standard of care in our transplant centre to reduce NRM caused by endothelial injury. Here, we retrospectively analysed the impact of SEP on clinical outcome in a cohort of 347 alloSCT patients.

RESULTS

SEP (n = 209) was associated with significantly reduced NRM (hazard ratio 0.61, 95% CI 0.38-0.96) and better overall survival (OS) after acute graft-versus-host disease (HR 0.59, 95% CI 0.37-0.93). Subgroup analyses showed that the NRM benefit was mainly found in patients with an intermediate endothelial activation and stress index (EASIX), while relapse risk was not affected. On day 100 post-alloSCT, patients receiving SEP had significantly higher levels of the rate-limiting enzyme of tryptophan metabolism, indoleamine 2,3-dioxygenase (IDO), higher kynurenine to tryptophan ratios as a proxy of IDO activity and tended to have lower levels of the endothelial injury marker ST2 (p = .055). No significant differences in interferon-gamma or IL18 levels were observed. These biomarker signatures suggest that the beneficial effects of SEP might be mediated by both endothelial protection and immunomodulation.

CONCLUSIONS

Together, these data suggest that SEP improves NRM and OS post-alloSCT in particular in patients with intermediate endothelial risk and provide first mechanistic clues about its potential mode of action.

Impact of Resistance Exercise and Nutritional Endorsement on physical performance in patients with GvHD (IRENE-G study) - design and rational of a randomized controlled trial

BACKGROUND

Graft-versus-host disease (GvHD) remains a major complication and limitation to successful allogeneic hematopoietic stem cell transplantation. Treatment of GvHD is challenging due to its heterogeneous nature of presentation, with steroids remaining the established first-line treatment. Long-term doses of systemic corticosteroids have many well-known side-effects including muscle atrophy. Despite the fact that reports in non-cancer clinical populations treated with glucocorticoids demonstrated that resistance training can reverse atrophy and weakness, no RCT has evaluated the potential of resistance training on preventing the disease- and treatment-induced loss of skeletal muscle mass and function in GvHD patients yet. In this context, ensuring adequate nutrition is important as protein deprivation may accelerate the wasting process. As GvHD patients are commonly found to be malnourished, nutritional medical care should be considered when investigating the effect of exercise in GvHD patients. Therefore, the aim of the present "Impact of Resistance Exercise and Nutritional Endorsement on physical performance in patients with GvHD" - Study (IRENE-G) is to evaluate the effects of resistance exercise in combination with nutritional endorsement on physical, nutritional and patient-reported outcomes in GvHD patients.

METHODS

IRENE-G is a 24-week prospective interventional RCT. One hundred twelve participants will be randomly allocated (1:1) to one of two arms: resistance exercise and nutritional optimization (experimental) vs. nutritional optimization only (control). Participants in the experimental group will engage in a supervised, progressive moderate-to-high intensity resistance training that is consistent with exercise guidelines for cancer patients, while additionally receiving nutritional support/therapy. Subjects of the control group solely receive nutritional support/therapy based on individual needs. Participants will be assessed at baseline, at 8, 16, 24 weeks for physical performance and various physiological, nutritional and patient-reported outcomes. Follow-up will be 6 months after intervention completion.

DISCUSSION

To our knowledge, this will be the first RCT to assess and compare the effects of a resistance intervention supplemented by nutritional support/therapy against nutritional support only on various health-related outcomes in GvHD patients. The study will contribute to our understanding of the value of exercise and nutritional endorsement in counteracting the negative consequences of GvHD and its treatment.

TRIAL REGISTRATION

ClinicalTrials.gov : NCT05111834 . Registered 8 November 2021 - Retrospectively registered.

EASIX and Severe Endothelial Complications After CD19-Directed CAR-T Cell Therapy—A Cohort Study

Background

Endothelial dysfunction is associated with two main complications of chimeric antigen receptor T (CAR-T) cell therapy, cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS). This study evaluates the Endothelial Activation and Stress Index (EASIX) as a prognostic marker for high-grade CRS and ICANS in patients treated with CD19-directed CAR-T cells.

Methods

In this retrospective study, a training cohort of 93 patients from the ZUMA-1 trial and a validation cohort of 121 patients from two independent centers (University Hospital Heidelberg, Charité University Medicine Berlin) were investigated. The primary objective was to assess the predictive capacity of EASIX measured immediately before the start of lymphodepletion (EASIX-pre) for the occurrence of grade ≥3 CRS and/or ICANS. To explore a possible endothelial link, serum levels of endothelial stress markers (angiopoietin-2, suppressor of tumorigenicity-2, soluble thrombomodulin, and interleukin-8) were determined before lymphodepletion and on day 7 after CART infusion in the validation cohort (n = 47).

Results

The prognostic effect of EASIX-pre on grade ≥3 CRS and/or ICANS was significant in the training cohort [OR 2-fold increase 1.72 (1.26–2.46)] and validated in the independent cohort. An EASIX-pre cutoff >4.67 derived from the training cohort associated with a 4.3-fold increased odds ratio of severe CRS/ICANS in the independent cohort. Serum endothelial distress markers measured on day+7 correlated with EASIX-pre and associated with severe complications.

Conclusions

EASIX-pre is a powerful predictor of severe CRS/ICANS after CD19-directed CART therapy and might be used as a basis for risk-adapted prevention strategies.

Response to extracorporeal photopheresis therapy of patients with steroid-refractory/-resistant GvHD is associated with up-regulation of Th22 cells and Tfh cells

Extracorporeal photopheresis (ECP), a personalized cellular immunotherapy, constitutes a promising treatment for steroid-refractory/-resistant graft-versus-host disease (SR-GvHD), with encouraging clinical response rates. To further investigate its mechanism of action, ECP's effects on T helper (Th) cells as well as on expression of immune checkpoint (PD-1 and Tim-3) and apoptotic (Fas receptor [FasR]) molecules were investigated in 27 patients with SR-GvHD. Our data show that GvHD patients had significantly higher levels of Th2, Th17, Th22 and granulocyte-macrophage colony-stimulating factor (GM-CSF)-positive Th (ThG) cells and clearly lower levels of T follicular helper (Tfh) cells, including Th1- and Th2-like cells, compared with healthy donors. ECP therapy for GvHD was effective through the modulation of different Th subsets: increases of Th22 (1.52-fold) and Tfh cells (1.48-fold) in acute GvHD (aGvHD) and increases of Th2-like Tfh cells (1.74-fold) in chronic GvHD (cGvHD) patients were associated with clinical response. Expression of FasR was further upregulated in CD4⁺CD8⁺ T cells. Additionally, Tim-3-expressing effector T cells associated with the severity of GvHD were reduced. Taken together, these data show that ECP therapy exerts immunomodulatory effects by promoting a balanced immune reconstitution and inducing immune tolerance. Therefore it represents an attractive option for the treatment of GvHD.

Kynurenine pathway activation and deviation to anthranilic and kynurenic acid in fibrosing chronic graft-versus-host disease

Fibrosing chronic graft-versus-host disease (cGVHD) is a debilitating complication of allogeneic stem cell transplantation (alloSCT). A driver of fibrosis is the kynurenine (Kyn) pathway, and Kyn metabolism patterns and cytokines may influence cGVHD severity and manifestation (fibrosing versus gastrointestinal [GI] cGVHD). Using a liquid chromatography-tandem mass spectrometry approach on sera obtained from 425 patients with allografts, we identified high CXCL9, high indoleamine-2,3-dioxygenase (IDO) activity, and an activated Kyn pathway as common characteristics in all cGVHD subtypes. Specific Kyn metabolism patterns could be identified for non-severe cGVHD, severe GI cGVHD, and fibrosing cGVHD, respectively. Specifically, fibrosing cGVHD was associated with a distinct pathway shift toward anthranilic and kynurenic acid, correlating with reduced activity of the vitamin-B2-dependent kynurenine monooxygenase, low vitamin B6, and increased interleukin-18. The Kyn metabolite signature is a candidate biomarker for severe fibrosing cGVHD and provides a rationale for translational trials on prophylactic vitamin B2/B6 supplementation for cGVHD prevention.

High IDO activity and an activated Kyn pathway are common in all cGVHD subtypes

Specific Kyn metabolism patterns were identified for gastrointestinal and fibrosing cGVHD

A pathway shift toward anthranilic and kynurenic acid was found in fibrosing cGVHD

A rationale for vitamin B2/B6 adjustment for cGVHD prevention is presented

Allogeneic hematopoietic cell transplantation in patients with myelodysplastic syndrome using treosulfan based compared to other reduced-intensity or myeloablative conditioning regimens. A report of the chronic malignancies working party of the EBMT

Allogeneic haematopoietic-cell transplantation (allo-HCT) is a potentially curative therapy for high-risk myelodysplastic syndrome (MDS). Reduced-intensity conditioning (RIC) is usually associated with lower non-relapse mortality (NRM), higher relapse rate and similar overall-survival (OS) as myeloablative-conditioning (MAC). Fludarabine/treosulfan (FT) is a reduced-toxicity regimen with intense anti-leukaemia activity and a favourable toxicity profile. We investigated post-transplant outcomes in 1722 MDS patients following allo-HCT with FT (n = 367), RIC (n = 687) or MAC (n = 668). FT and RIC recipients were older than MAC recipients, median age 59, 59 and 51 years, respectively (P < 0·001) but other disease characteristics were similar. The median follow-up was 64 months (1-171). Five-year relapse rates were 25% (21-30), 38% (34-42) and 25% (22-29), after FT, RIC and MAC, respectively, (P < 0·001). NRM was 30% (25-35), 27% (23-30) and 34% (31-38, P = 0·008), respectively. Five-year OS was 50% (44-55), 43% (38-47), and 43% (39-47), respectively (P = 0·03). In multivariate analysis, FT was associated with a lower risk of relapse (HR 0·55, P < 0·001) and better OS (HR 0·72, P = 0·01). MAC was associated with higher NRM (HR 1·44, P = 0·001). In conclusion, FT is associated with similar low relapse rates as MAC and similar low NRM as RIC, resulting in improved OS. FT may be the preferred regimen for allo-HCT in MDS.

Early bilirubinemia after allogeneic stem cell transplantation-an endothelial complication

Hyperbilirubinemia occurs frequently after allogeneic stem cell transplantation. Causes include primary liver damage and endothelial complications as major contributors. Here, we have investigated the impact of early bilirubinemia (EB) on posttransplant outcomes. Maximum total bilirubin levels (days 0-28) were categorized using maximally selected log rank statistics to identify a cut off for the endpoint non-relapse mortality (NRM) in a training cohort of 873 patients. EB above this cut off was correlated with NRM and overall survival (OS) and with pre- and posttransplant Angiopoietin-2, interleukin (IL)18, CXCL8 and suppressor of tumorigenicity-2 (ST2) serum levels, and the endothelial activation and stress index (EASIX). Clinical correlations were validated in a sample of 388 patients transplanted in an independent institution. The EB cut off was determined at 3.6 mg/dL (61.6 µM). EB predicted OS (HR 1.60, 95% CI 1.21-2.12, p < 0.001), and NRM (CSHR 2.14; 1.28-3.56, p = 0.004), also independent of typical endothelial complications such as veno-occlusive disease, refractory acute graft-versus-host disease, or transplant-associated microangiopathy. However, EB correlated with high Angiopoietin-2, EASIX-pre and EASIX-day 0, as well as increased levels of posttransplant CXCL8, IL18, and ST2. In summary, EB indicates a poor prognosis. The association of EB with endothelial biomarkers suggests an endothelial pathomechanism also for this posttransplant complication.

EASIX for Prediction of Outcome in Hospitalized SARS-CoV-2 Infected Patients

Background

The coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and has evoked a pandemic that challenges public health-care systems worldwide. Endothelial cell dysfunction plays a key role in pathophysiology, and simple prognosticators may help to optimize allocation of limited resources. Endothelial activation and stress index (EASIX) is a validated predictor of endothelial complications and outcome after allogeneic stem cell transplantation. Aim of this study was to test if EASIX could predict life-threatening complications in patients with COVID-19.

Methods

SARS-CoV-2-positive, hospitalized patients were enrolled onto a prospective non-interventional register study (n=100). Biomarkers were assessed at hospital admission. Primary endpoint was severe course of disease (mechanical ventilation and/or death, V/D). Results were validated in 126 patients treated in two independent institutions.

Results

EASIX at admission was a strong predictor of severe course of the disease (odds ratio for a two-fold change 3.4, 95%CI 1.8-6.3, p<0.001), time to V/D (hazard ratio (HR) for a two-fold change 2.0, 95%CI 1.5-2.6, p<0.001) as well as survival (HR for a two-fold change 1.7, 95%CI 1.2-2.5, p=0.006). The effect was retained in multivariable analysis adjusting for age, gender, and comorbidities and could be validated in the independent cohort. At hospital admission EASIX correlated with increased suppressor of tumorigenicity-2, soluble thrombomodulin, angiopoietin-2, CXCL8, CXCL9 and interleukin-18, but not interferon-alpha.

Conclusion

EASIX is a validated predictor of COVID19 outcome and an easy-to-access tool to segregate patients in need for intensive surveillance.

A prognostic score including mutation profile and clinical features for patients with CMML undergoing stem cell transplantation

The inclusion of mutation status improved risk stratification for newly diagnosed patients with chronic myelomonocytic leukemia (CMML). Stem cell transplantation is a potentially curative treatment option, and patient selection is critical because of relevant transplant-related morbidity and mortality. We aimed to evaluate the impact of mutation status together with clinical presentations on posttransplant outcome. Our study included 240 patients with a median follow-up of 5.5 years. A significant association with worse survival was identified for the presence of mutations in ASXL1 and/or NRAS. In multivariable analysis, ASXL1- and/or NRAS-mutated genotype (hazard ratio [HR], 1.63), marrow blasts >2% (HR, 1.70), and increasing comorbidity index (continuous HR, 1.16) were independently associated with worse survival. A prognostic score (CMML transplant score) was developed, and the following points were assigned: 4 points for an ASXL1- and/or NRAS-mutated genotype or blasts >2% and 1 point each for an increase of 1 in the comorbidity index. The CMML transplant score (range, 0-20) was predictive of survival and nonrelapse mortality (P < .001 for both). Up to 5 risk groups were identified, showing 5-year survival of 81% for a score of 0 to 1, 49% for a score of 2 to 4, 43% for a score of 5 to 7, 31% for a score of 8 to 10, and 19% for a score >10. The score retained performance after validation (concordance index, 0.68) and good accuracy after calibration. Predictions were superior compared with existing scores designed for the nontransplant setting, which resulted in significant risk reclassification. This CMML transplant score, which incorporated mutation and clinical information, was prognostic in patients specifically undergoing transplantation and may facilitate personalized counseling.

Polymorphisms in CXCR3 ligands predict early CXCL9 recovery and severe chronic GVHD

Chronic graft-versus-host disease (cGVHD) is a major cause of mortality and morbidity after allogeneic stem cell transplantation (alloSCT). The individual risk of severe cGVHD remains difficult to predict and may involve CXCR3 ligands. This study investigated the role of single-nucleotide polymorphisms (SNPs) of CXCL4, CXCL9, CXCL10, and CXCL11, and their day +28 serum levels, in cGVHD pathogenesis. Eighteen CXCR3 and CXCL4, CXCL9-11 SNPs as well as peri-transplant CXCL9-11 serum levels were analyzed in 688 patients without (training cohort; n = 287) or with statin-based endothelial protection cohort (n = 401). Clinical outcomes were correlated to serum levels and SNP status. Significant polymorphisms were further analyzed by luciferase reporter assays. Findings were validated in an independent cohort (n = 202). A combined genetic risk comprising four CXCR3 ligand SNPs was significantly associated with increased risk of severe cGVHD in both training cohort (hazard ratio (HR) 2.48, 95% confidence interval (CI) 1.33-4.64, P = 0.004) and validation cohort (HR 2.95, 95% CI 1.56-5.58, P = 0.001). In reporter assays, significantly reduced suppressive effects of calcineurin inhibitors in constructs with variant alleles of rs884304 (P < 0.001) and rs884004 (P < 0.001) were observed. CXCL9 serum levels at day +28 after alloSCT correlated with both genetic risk and risk of severe cGVHD (HR 1.38, 95% CI 1.10-1.73, P = 0.006). This study identifies patients with high genetic risk to develop severe cGVHD.

Predicting sinusoidal obstruction syndrome after allogeneic stem cell transplantation with the EASIX biomarker panel

No biomarker panel has been established for prediction of sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD), a major complication of allogeneic stem cell transplantation (alloSCT). We compared the potential of the Endothelial Activation and Stress Index (EASIX), based on lactate dehydrogenase, creatinine, and thrombocytes, with that of the SOS/VOD clinical risk score of the Center for International Blood and Marrow Transplant Research (CIBMTR) to predict SOS/VOD in two independent cohorts. In a third cohort, we studied the impact of endothelium-active prophylaxis with pravastatin and ursodeoxycholic acid (UDA) on SOS/VOD risk. The cumulative incidence of SOS/VOD within 28 days after alloSCT in the training cohort (Berlin, 2013-2015, n=446) and in the validation cohort (Heidelberg, 2002-2009, n=380) was 9.6% and 8.4%, respectively. In both cohorts, EASIX assessed at the day of alloSCT (EASIX-d0) was significantly associated with SOS/VOD incidence (P<0.0001), overall survival (OS), and non-relapse mortality (NRM). In contrast, the CIBMTR score showed no statistically significant association with SOS/VOD incidence, and did not predict OS and NRM. In patients receiving pravastatin/UDA, the cumulative incidence of SOS/VOD was significantly lower at 1.7% (Heidelberg, 2010-2015, n=359, P<0.0001) than in the two cohorts not receiving pravastatin/UDA. The protective effect was most pronounced in patients with high EASIX-d0. The cumulative SOS/VOD incidence in the highest EASIX-d0 quartiles were 18.1% and 16.8% in both cohorts without endothelial prophylaxis as compared to 2.2% in patients with pravastatin/UDA prophylaxis (P<0.0001). EASIX-d0 is the first validated biomarker for defining a subpopulation of alloSCT recipients at high risk for SOS/VOD. Statin/UDA endothelial prophylaxis could constitute a prophylactic measure for patients at increased SOS/VOD risk.

Clinical Response to the CD95-Ligand Inhibitor Asunercept Is Defined by a Pro-Inflammatory Serum Cytokine Profile

Simple Summary

Asunercept showed promising clinical efficacy in anemic, transfusion-dependent patients with low and intermediate risk myelodysplastic syndrome. In this retrospective post hoc analysis, serum levels of biomarkers were measured in study patients focusing on cytokines associated with erythropoiesis, inflammation, apoptosis, bone marrow fibrosis, and inflammasome activity. Baseline serum biomarkers were correlated with treatment response in order to propose a hypothetical responder serum profile. Response to asunercept was associated with improved overall survival. Higher baseline values of interleukin-18 (IL-18), S100 calcium-binding protein A9 (S100A9) and soluble p53 were predictive of non-response to asunercept. Non-responding patients showed a distinct, pro-inflammatory serum cytokine profile which was persistent throughout the first half of the treatment phase and appeared unaffected by asunercept. Our post hoc analysis suggests that serum cytokine profiling based on IL-18, S100A9 and soluble p53 may represent an approach to identify and select low-risk myelodysplastic syndrome patients most likely to benefit from asunercept treatment.

Abstract

Asunercept (APG101) is a well-tolerated CD95-ligand inhibitor that showed promising efficacy in a prospective, single-arm phase I study in anemic, transfusion-dependent patients with low and intermediate risk myelodysplastic syndrome (MDS). In this retrospective post hoc analysis, serum levels of biomarkers were measured in study patients focusing on cytokines associated with erythropoiesis, inflammation, apoptosis, bone marrow fibrosis, and inflammasome activity. Baseline serum biomarkers were correlated with treatment response, in order to propose a hypothetical responder serum profile. After an updated median follow-up of 54 months (range 7–65), response to asunercept was associated with improved overall survival (at 3-years: 67% [95%CI 36–97] versus 13% [95%CI 0–36] in responders versus non-responders, respectively). Higher baseline values of interleukin-18 (IL-18), S100 calcium-binding protein A9 (S100A9) and soluble p53 were predictive of non-response to asunercept (area under the receiver operating characteristic curve 0.79–0.82). Furthermore, non-responding patients showed a distinct, pro-inflammatory serum cytokine profile which was persistent throughout the first half of the treatment phase and appeared unaffected by asunercept. Although prospective validation is required, our post hoc analysis suggests that serum cytokine profiling based on IL-18, S100A9 and soluble p53 may represent an approach to identify and select low-risk MDS patients most likely to benefit from asunercept treatment.

Letermovir prophylaxis is effective in preventing cytomegalovirus reactivation after allogeneic hematopoietic cell transplantation: single-center real-world data

Morbidity and mortality after allogeneic hematopoietic cell transplantation (alloHCT) are still essentially affected by reactivation of cytomegalovirus (CMV). We evaluated 80 seropositive patients transplanted consecutively between March 2018 and March 2019 who received letermovir (LET) prophylaxis from engraftment until day +100 and retrospectively compared them with 80 patients without LET allografted between January 2017 and March 2018. The primary endpoint of this study was the cumulative incidence (CI) of clinically significant CMV infection (CS-CMVi) defined as CMV reactivation demanding preemptive treatment or CMV disease. With 14% CI of CS-CMVi at day +100 (11 events) was significantly lower in the LET cohort when compared to the control group (33 events, 41%; HR 0.29; p < 0.001). Whereas therapy with foscarnet could be completely avoided in the LET group, 7 out of 80 patients in the control cohort received foscarnet, resulting in 151 extra in-patient days for foscarnet administration (p = 0.002). One-year overall survival was 72% in the control arm vs 84% in the LET arm (HR 0.75 [95%CI 0.43–1.30]; p < 0.306). This study confirms efficacy and safety of LET for prophylaxis of CS-CMVi after alloHCT in a real-world setting, resulting in a significant patient benefit by reducing hospitalization needs and exposure to potentially toxic antiviral drugs for treatment of CMV reactivation.

Interleukin-18 and Hematopoietic Recovery after Allogeneic Stem Cell Transplantation

Simple Summary

We have previously shown that high pre-conditioning levels of Interleukin-18 were associated with worse survival after allogeneic stem cell transplantation due to increased non-relapse mortality. While no correlations with acute graft-versus-host disease were observed, interleukin-18-related excess mortality was mainly driven by fatal infectious complications. In multiple studies, delayed hematopoietic recovery and poor graft function following allogeneic stem cell transplantation has been demonstrated as a powerful predictor of non-relapse mortality. The present study links high interleukin-18 to delayed platelet recovery in allografted patients. Given the functions of interleukin-18 in regulating the quiescence of hematopoietic stem/progenitor cells, our findings may be explained by Interferon gamma-independent inhibitory effects of interleukin-18 on stem cell proliferation and hematopoietic reconstitution in allografted patients. Importantly, considering recent successful interleukin-18-neutralizing approaches in autoimmune disorders, our results provide a rationale to explore modulation of interleukin-18 for improving hematopoietic recovery and outcomes in allogeneic stem cell transplantation recipients.

Abstract

Interleukin-18 (IL-18) is an immunoregulatory cytokine and a context-dependent regulator of hematopoietic stem/progenitor cell (HSPC) quiescence in murine models. In a previous study, high pre-conditioning levels of IL-18 were associated with increased non-relapse mortality (NRM) after allogeneic stem cell transplantation (alloSCT). To investigate the clinical impact of IL-18 status on hematopoietic function, the associations of pre-conditioning and day 0–3 cytokine levels with platelet and neutrophil recovery were analyzed in a training cohort of 714 allografted patients. In adjusted logistic regression analyses, both increasing pre-conditioning and day 0–3 IL-18 levels had a significantly higher adjusted odds ratio (aOR) of delayed platelet and neutrophil recovery on day +28 post-transplant (aOR per two-fold increase: 1.6–2.0). The adverse impact of high pre-conditioning IL-18 on day +28 platelet recovery was verified in an independent cohort of 673 allografted patients (aOR per two-fold increase: 1.8 and 1.7 for total and free IL-18, respectively). In both cohorts, a platelet count ≤20/nL on day +28 was associated with a significantly increased hazard of NRM (hazard ratio 2.13 and 2.94, respectively). Our findings support the hypothesis that elevated peritransplant IL-18 levels affect post-transplant HSPC function and may provide a rationale to explore modulation of IL-18 for improving alloSCT outcomes.

The impact of allogeneic hematopoietic cell transplantation on the mortality of poor-risk non-Hodgkin lymphoma: an intent-to-transplant analysis

Purpose of this single-centre retrospective study was to assess the outcome of allogeneic hematopoietic cell transplantation (alloHCT) for relapsed/refractory (r/r) non-Hodgkin lymphoma (NHL) by intent-to-transplant (ITT). Included were all consecutive patients with diffuse large B-cell lymphoma (DLBCL), follicular lymphoma (FL), mantle cell lymphoma (MCL), and peripheral T-cell lymphoma (PTCL) for whom a donor search was performed between 2004 and 2018. Primary endpoint was overall survival (OS) measured from search initiation. A donor search was initiated for 189 patients (DLBCL 61, FL 32, MCL 43, and PTCL 53), with 76% of the patients having active disease. OS at 5 years after search initiation for DLBCL, FL, MCL, and PTCL was 26%, 44%, 52%, and 50%, respectively. AlloHCT was performed in 137 patients (72%; DLBCL 64%). Main reason for not undergoing alloHCT was disease progression, whereas donor unavailability accounted for only 4% of pretransplantation failures. These results suggest that survival of patients with r/r NHL entering the alloHCT route may be overestimated by a factor of 1.2-1.4 if based on actually transplanted patients only. This effect should be taken into account when using alloHCT as benchmark for new therapeutic approaches for the treatment of poor-risk NHL.

Influencing factors of cardiorespiratory fitness in allogeneic stem cell transplant candidates prior to transplantation

PURPOSE

Cardiorespiratory fitness (CRF) seems to be prognostic prior to allogeneic stem cell transplantation (allo-HSCT). Influencing factors of CRF in allo-HSCT candidates have not been studied so far. Aim was to identify potentially influencing factors on CRF.

METHODS

To assess CRF, a maximal cardiopulmonary exercise test (CPET) was performed on average 2.6 ± 7.2 days prior to admission. A regression analysis was conducted, with the following predictors: gender, age, body mass index (BMI), time between last therapy and allo-HSCT (t_Therapies), number of cardiotoxic therapies (n_Cardiotox), number of transplantations (n_Transplantations), comorbidity index (HCT-CI), hemoglobin level of the last 3 months (area under the curve), and physical activity.

RESULTS

A total of 194 patients performed a CPET. VO_2peak was significantly reduced compared with reference data. In total, VO_2peak was 21.4 ml/min/kg (- 27.5%, p < 0.05). Men showed a significant larger percentage difference from reference value (- 29.1%, p < 0.05) than women (- 24.4%). VO_2peak was significantly (p < 0.05) influenced by age (β = - 0.11), female gender (β = - 3.01), BMI (β = - 0.44), n_Cardiotox (β = - 0.73), hemoglobin level (β = 0.56), and physical activity prior to diagnosis (β = 0.10).

CONCLUSIONS

Our study demonstrates a decreased CRF indicating the potential need of prehabilitative exercise. We revealed some influencing factors on CRF. Those patients could benefit the most from exercise.

High leukemia-free survival after TBI-based conditioning and mycophenolate mofetil-containing immunosuppression in patients allografted for chronic myelomonocytic leukemia: a single-center experience

This retrospective single-center analysis studied the impact of the conditioning and the graft-versus-host disease (GVHD) prophylaxis on outcome in unselected patients allografted for chronic myelomonocytic leukemia (CMML) and acute myeloid leukemia (AML) secondary to documented prior CMML. A total of 44 patients (median age 61 years) allografted between 2002 and 2019 in our institution were analyzed. Fifteen patients had secondary AML. The conditioning regimen was fractionated 6-8 Gy total body irradiation (TBI) in combination with fludarabine in 33 (75%) patients. Eleven patients (25%) received alkylator-based conditioning therapy without TBI. For GVHD prophylaxis, a calcineurin inhibitor (CNI) backbone in combination with methotrexate (MTX) or mycophenolate mofetil (MMF) was applied in 21 and 23 patients, respectively. All patients allografted from an unrelated donor (UD) received antithymocyte globuline. In univariate analysis of the entire cohort, TBI-based conditioning and MMF-containing immunosuppression were associated with improved leukemia-free survival (LFS, HR 0.16, P < 0.001 and HR 0.41, P = 0.030, respectively). After stratification according to conditioning and GVHD prophylaxis into four groups (TBI-MMF [n = 17], TBI-MTX [n = 16], alkylator-MMF [n = 6], alkylator-MTX [n = 5]), TBI-MMF was associated with improved overall survival (OS) and LFS (P = 0.001 and P < 0.001, respectively). Patient and disease characteristics did not differ between the groups. The associations of TBI-based conditioning and MMF with prolonged LFS were observed across the CMML (n = 29), secondary AML (n = 15), and UD allograft (n = 34) subgroups. In summary, our study suggests that allografting based on intermediate-dose TBI conditioning and MMF-containing GVHD prophylaxis is associated with increased disease control in CMML. Larger (registry-based) studies are warranted to confirm our findings.

EASIX for prediction of survival in lower-risk myelodysplastic syndromes

Patients with myelodysplastic syndromes (MDS) are at risk of early death from cardiovascular complications due to the link between clonal hematopoiesis and endothelial dysfunction. EASIX (Endothelial Activation and Stress Index) has been established to predict endothelial complications after allogeneic transplantation. We investigated the impact of EASIX measured at first diagnosis on survival of patients with lower- and higher-risk MDS (no allogeneic transplantation) in two independent institutions: n = 192 (training cohort) and n = 333 (validation cohort). Serum markers of endothelial cell distress were measured and correlated to EASIX. While no effects of EASIX on survival were observed in higher-risk patients, EASIX was associated with shorter survival in patients with lower-risk MDS in both cohorts (univariate: Cohort I: hazard ratio (HR): 1.46; 95% confidence interval (CI) 1.24–1.71; p-value < 0.001/Cohort II: HR 1.31 [1.17–1.48]; p-value < 0.001). Multivariate Cox regression analysis and prediction error analyses confirmed that EASIX remained a significant predictor of survival after adjustment for age, sex, cytogenetic abnormalities and bone marrow blasts in lower-risk patients. The model of the training cohort could be validated. Serum levels of Angiopioetin-2 correlated significantly with EASIX. We introduce EASIX as an easily accessible and independent predictor for survival in patients with lower-risk MDS.

Interleukin-18 and outcome after allogeneic stem cell transplantation: A retrospective cohort study

Background

Interleukin-18 (IL-18) is involved in endothelial activation and dysfunction, and in the pathogenesis and severity of acute graft-versus-host disease (aGVHD). Its relevance for patient outcome after allogeneic stem cell transplantation (alloSCT) has not yet been comprehensively addressed.

Methods

Pre-transplant serum levels of free IL-18 were retrospectively assessed in a cohort of 589 patients (training cohort). Results were validated in 688 patients allografted in a different centre. The primary endpoint was overall survival (OS). Secondary endpoints included incidences of non-relapse mortality (NRM), relapse, and aGVHD.

Findings

In the training cohort, higher pre-transplant levels of free IL-18 were significantly associated with worse OS (hazard ratio [HR] per 1-log2 increase, 1.25, P = 0.008) in multivariable models. This was due to a higher hazard of NRM (HR per 1-log2 increase, 1.39, P = 0.001), rather than relapse. The associations of pre-transplant free IL-18 with higher NRM (HR per 1-log2 increase, 1.24, P = 0.02) and shorter OS (HR per 1-log2 increase, 1.22, P = 0.006) were confirmed in the validation cohort. In both cohorts, the correlations of higher pre-transplant free IL-18 serum levels with increased NRM and worse OS were mainly driven by fatal infectious complications. No associations with incidence of aGVHD were observed.

Interpretation

Higher pre-transplant levels of free IL-18 were associated with non-relapse and overall mortality after alloSCT. Our results may provide a rationale for prospective studies evaluating IL-18 status and inhibition of IL-18 activity in patients undergoing allografting.

Pre-transplant testosterone and outcome of men after allogeneic stem cell transplantation

Testosterone is an important determinant of endothelial function and vascular health in men. As both factors play a role in mortality after allogeneic stem cell transplantation (alloSCT), we retrospectively evaluated the impact of pre-transplant testosterone levels on outcome in male patients undergoing alloSCT. In the discovery cohort (n=346), an impact on outcome was observed only in the subgroup of patients allografted for acute myeloid leukemia (AML) (n=176, hereafter termed ‘training cohort’). In the training cohort, lower pre-transplant testosterone levels were significantly associated with shorter overall survival (OS) [hazard ratio (HR) for a decrease of 100 ng/dL: 1.11, P=0.045]. This was based on a higher hazard of non-relapse mortality (NRM) (cause-specific HR: 1.25, P=0.013), but not relapse (cause-specific HR: 1.06, P=0.277) in the multivariable models. These findings were replicated in a confirmation cohort of 168 male patients allografted for AML in a different center (OS, HR: 1.15, P=0.012 and NRM, cause-specific HR: 1.23; P=0.008). Next, an optimized cut-off point for pre-transplant testosterone was derived from the training set and evaluated in the confirmation cohort. In multivariable models, low pre-transplant testosterone status (<250 ng/dL) was associated with worse OS (hazard ratio 1.95, P=0.021) and increased NRM (cause-specific HR 2.68, P=0.011) but not with relapse (cause-specific HR: 1.28, P=0.551). Our findings may provide a rationale for prospective studies on testosterone/androgen assessment and supplementation in male patients undergoing alloSCT for AML.

Shaping of CD56bri Natural Killer Cells in Patients With Steroid-Refractory/Resistant Acute Graft-vs.-Host Disease via Extracorporeal Photopheresis

CD56^bri natural killer (NK) cells play an important role in the pathogenesis of graft-vs. -host disease (GVHD) and immune defense in the early period after allogeneic hematopoietic stem cell transplantation. Extracorporeal photopheresis (ECP) as an immunomodulating therapy has been widely used for GVHD treatment. However, the mechanism of action of ECP still remains to be elucidated, particularly the influence of ECP on NK cells. Thirty-four patients with steroid-refractory/resistant acute GVHD (aGVHD) ≥ °II and moderate to severe chronic GVHD (cGVHD) received ECP therapy. Patient samples obtained during intensive and long-term treatment were analyzed. Immunomonitoring with respect to cell phenotype and function was performed on rested peripheral blood mononuclear cells (PBMCs) using multiparametric flow cytometry. NK activity in terms of cytokine release was analyzed by intracellular cytokine staining after co-culture with K562 cells. Moreover, the proliferative capacity of NK cells, CD4⁺, and CD8⁺ T cells was determined by carboxyfluorescein succinimidyl ester (CFSE) staining. Clinically, 75% of aGVHD and 78% of cGVHD patients responded to ECP therapy. Moreover, our data show that aGVHD, cGVHD patients and healthy donors (HDs) present distinct NK patterns: aGVHD patients have a higher frequency of CD56^bri NK subsets with stronger NKG2D and CD62L expression, while CD56⁻CD16⁺ NK cells with higher expression of CD57 and CD11b stand out as a signature population for cGVHD. ECP therapy could significantly decrease CD56^briCD16⁻ NK cells with shifting the quality from a cytotoxic to a regulatory pattern and additionally mature CD56^dim NK cells via upregulation of CD57 in complete responding aGVHD patients. Moreover, ECP could keep the anti-viral and anti-leukemic effects intact via maintaining specialized anti-viral/leukemic CD57⁺NKG2C⁺CD56^dim NK cells as well as remaining the quality and quantity of cytokine release by NK cells. The proliferative capacity of effector cells remained constant over ECP therapy. In conclusion, ECP represents an attractive option to treat GVHD without compromising anti-viral/leukemic effects. Shaping of CD56^bri NK cell compartment by downregulating the cytotoxic subset while upregulating the regulatory subset contributes to the mechanisms of ECP therapy in aGVHD.

Asymmetric dimethylarginine serum levels are associated with early mortality after allogeneic stem cell transplantation

Increasing evidence suggests that endothelial cell distress is associated with mortality after allogeneic stem cell transplantation and acute graft-versus-host disease. Asymmetric dimethylarginine is an endogenous nitric oxide synthase inhibitor that induces endothelial cell dysfunction. We analyzed the impact of pre-transplant serum levels of asymmetric dimethylarginine on outcome after allogeneic stem cell transplantation. Since acute graft-versus-host disease and its treatment are major contributors to post-transplant mortality, the effect of asymmetric dimethylarginine on outcome measures was also assessed after onset of acute graft-versus-host disease. A total of 938 patients allografted at two centers between 2002 and 2013 were included in the retrospective study. In multivariable models, higher pre-transplant asymmetric dimethylarginine levels were significantly associated with an increased risk of non-relapse mortality (hazard ratio 1.43 per 1-log₂ increase, P=0.005) but not with relapse (hazard ratio 1.21, P=0.109) within the first year after transplantation. This translated into worse overall survival (hazard ratio 1.45, P<0.0001) and shorter progression-free survival (hazard ratio 1.30, P=0.002) in the first year after transplantation. Higher pre-transplant asymmetric dimethylarginine levels were also associated with shorter overall survival (hazard ratio 1.46, P=0.001) and progression-free survival (hazard ratio 1.32, P=0.010) and higher non-relapse mortality (hazard ratio 1.36, P=0.042) within 1 year after the onset of acute graft-versus-host disease. Taken together, our data indicate an association between pre-transplant asymmetric dimethylarginine status and early non-relapse mortality in allografted patients, both overall and after the onset of acute graft-versus-host disease. These findings underline the relevance of endothelial dysfunction for transplant complications.

Modulation of B Cells and Homing Marker on NK Cells Through Extracorporeal Photopheresis in Patients With Steroid-Refractory/Resistant Graft-Vs.-Host Disease Without Hampering Anti-viral/Anti-leukemic Effects

Graft-vs.-host disease (GvHD), a severe complication of allogeneic hematopoietic stem cell transplantation, significantly affects the post-transplant morbidity and mortality. Systemic steroids remain the gold standard for the initial management of GvHD. However, up to 60% of patients will not sufficiently respond to steroids. Extracorporeal photopheresis (ECP), a cell-based immunotherapy, has shown good clinical results in such steroid-refractory/resistant GvHD patients. Given its immunomodulatory, but not global immunosuppressive and steroid-sparing capacity, ECP constitutes an attractive option. In the case of GvHD, the balance of immune cells is destroyed: effector cells are not any longer efficiently controlled by regulatory cells. ECP therapy may restore this balance. However, the precise mechanism and the impact of ECP on anti-viral/anti-leukemic function remain unclear. In this study, 839 ECP treatments were performed on patients with acute GvHD (aGvHD) and chronic GvHD (cGvHD). A comprehensive analysis of effector and regulatory cells in patients under ECP therapy included multi-parametric flow cytometry and tetramer staining, Luminex^TM-based cytokine, interferon-γ enzyme-linked immunospot, and chromium-51 release assays. Gene profiling of myeloid-derived suppressor cells (MDSCs) was performed by microarray analysis. Immunologically, modulations of effector and regulatory cells as well as proinflammatory cytokines were observed under ECP treatment: (1) GvHD-relevant cell subsets like CD62L⁺ NK cells and newly defined CD19^hiCD20^hi B cells were modulated, but (2) quantity and quality of anti-viral/anti-leukemic effector cells were preserved. (3) The development of MDSCs was promoted and switched from an inactivated subset (CD33^-CD11b⁺) to an activated subset (CD33⁺CD11b⁺). (4) The frequency of Foxp3⁺CD4⁺ regulatory T cells (Tregs) and CD24⁺CD38^hi regulatory B cells was considerably increased in aGvHD patients, and Foxp3⁺CD8⁺ Tregs in cGvHD patients. (5) Proinflammatory cytokines like IL-1β, IL-6, IL-8, and TNF-α were significantly reduced. In summary, ECP constitutes an effective immunomodulatory therapy for patients with steroid-refractory/resistant GvHD without impairment of anti-viral/leukemia effects.

A prospective study on serum Cytokeratin (CK)-18 and CK18 fragments as biomarkers of acute hepato-intestinal GVHD

Apoptotic intestinal crypt cells are pathognomonic of acute intestinal graft versus host disease (GVHD). Serum levels of the apoptotic degradation product cytokeratin-18 fragments (CK18F) were associated with acute hepato-intestinal GVHD. Here we present a prospective clinical observational trial (NCT00935324) investigating serum levels of total CK18 (tCK18) and apoptotic CK18F to predict imminent acute hepato-intestinal GVHD and response to treatment. Total (t)CK18 and CK18F kinetics were measured before transplantation and in weekly intervals thereafter. In total 109 patients were enrolled. Acute hepato-intestinal GVHD grade I-IV was suspected in 36 patients (33%) at a median of 56 days post-transplant, 12 of these patients developed steroid-refractory GVHD. Both tCK18 and apoptotic CK18F increased at GVHD onset, and distinguished patients with suspected acute hepato-intestinal GVHD who were negative in intestinal histology. In patients with clinical acute hepato-intestinal GVHD, tCK18 significantly raised already 7-14 days before symptom onset. In receiver operator characteristics, areas under the curve at GVHD onset were 0.927 (p < 0.001) for tCK18 and 0.875 (p < 0.001) for apoptotic CK18F for patients with proven hepato-intestinal acute GVHD. This prospective study validates CK18F and highlights tCK18 as specific biomarkers suitable for improving prediction and diagnosis of suspected imminent and clinically manifest acute hepato-intestinal GVHD.

CD7 is expressed on a subset of normal CD34-positive myeloid precursors

OBJECTIVE

To improve monitoring of myeloid neoplasms by flow cytometry-based minimal residual disease (MRD) analysis, we analyzed the significance of leukemia-associated immunophenotype (LAIP) markers in 44 patients.

METHODS

In a pilot study cohort, peripheral blood or bone marrow samples from 13 patients with myeloid neoplasms and one case of B lymphoblastic leukemia in complete hematologic remission after allogeneic bone marrow or stem cell transplantation were subjected to selection for leukemia-specific phenotypes by fluorescence-activated cell sorting using individual marker combinations, followed by PCR-based chimerism analysis.

RESULTS

The feasibility of this method could be demonstrated, with selection being successful in 12 cases, including two cases where mixed chimerism was found exclusively in sorted cells. Interestingly, four specimens displayed full donor chimerism in cells expressing the presumably aberrant combination CD34⁺ /CD7⁺ . Further analyses, including assessment of an independent cohort of 25 patients not affected by neoplastic bone marrow infiltration, revealed that normal myeloid precursors usually include a population coexpressing CD34, CD13, CD33, and CD7.

CONCLUSION

We conclude that the combination CD34⁺ /CD7⁺ might not be suitable as an LAIP for MRD diagnostics and that a subset of normal myeloid precursors in the bone marrow expresses CD7.

Single Nucleotide Polymorphisms in CD40L Predict Endothelial Complications and Mortality After Allogeneic Stem-Cell Transplantation

Purpose

Endothelial vulnerability is a potential risk factor for complications after allogeneic stem-cell transplantation (alloSCT). The CD40/CD40 ligand (CD40L) axis contributes to inflammatory diseases and is upregulated in endothelial cells upon activation, suggesting a role in alloSCT biology. Here, we studied single nucleotide polymorphisms (SNPs) in the CD40L gene in recipients of alloSCT.

Patients and Methods

Three CD40L SNPs (rs3092920, rs3092952, rs3092936) were analyzed for association with transplant-associated thrombotic microangiopathy, overall nonrelapse mortality (NRM), and NRM after acute graft-versus-host disease in 294 recipients of alloSCT without statin-based endothelial prophylaxis (SEP). The significant genotype was then put into perspective with established thrombomodulin ( THBD) gene polymorphisms. Findings were validated in an independent cohort without SEP and in an additional 344 patients who received SEP.

Results

The rs3092936 CC/CT genotype was associated with an increased risk of transplant-associated thrombotic microangiopathy ( P = .001), overall NRM ( P = .03), and NRM after acute graft-versus-host disease ( P = .01). The rs3092936 CC/CT genotype was largely mutually exclusive of high-risk THBD SNPs. Both CD40L and THBD SNPs predicted adverse overall survival (OS) and overall NRM to a similar extent in training cohort (OS, P = .04; NRM, P < .001) and validation cohort (OS, P = .01; NRM, P = .001) without SEP. In contrast, SEP completely abolished the influence of the high-risk CD40L and THBD SNPs ( P = .40).

Conclusion

An increased risk of endothelial complications can be predicted before alloSCT by genetic markers in the recipient’s genome. The normalization of mortality risks in patients treated with SEP suggests a way of overcoming the negative effect of high-risk genotypes and warrants further clinical validation.

Pretransplant Vitamin D Deficiency Is Associated With Higher Relapse Rates in Patients Allografted for Myeloid Malignancies

Purpose Vitamin D (VitD) deficiency is common in patients with hematologic malignancies undergoing allogeneic transplantation (alloSCT), but its prognostic relevance is unclear. Patients and Methods The impact of pretransplant VitD status on overall survival, relapse mortality, and nonrelapse mortality was investigated retrospectively in a cohort of 492 patients undergoing alloSCT at our center from 2002 to 2013. VitD deficiency was defined as a serum level of 25-hydroxyvitamin D3 < 20 ng/mL (equivalent to < 50 nM) before alloSCT and was assessed using accredited laboratory methods and a standard chemiluminescent immunoassay. Results were validated in an independent cohort of 398 patients diagnosed with myeloid malignancies. Results A total of 396 (80%) and 348 (87%) patients had VitD deficiency before alloSCT in the training and validation cohort, respectively. In the training cohort, VitD deficiency was significantly associated with inferior overall survival (hazard ratio [HR], 1.78; P = .007) in multivariable analysis. This was due to a higher risk of relapse (HR, 1.96; P = .006) rather than nonrelapse mortality. A significant association of pretransplant VitD deficiency with higher relapse rates was observed only in patients diagnosed with myeloid (HR, 2.55; P = .014) but not with lymphatic diseases (HR, 1.60; P = .147). A similar impact of pretransplant VitD deficiency on relapse risk in myeloid diseases was also observed in an independent patient cohort (HR, 2.60; P = .017). Validation of the effect of VitD deficiency on relapse in patients with myeloid malignancies was successful. Conclusion Pretransplant VitD deficiency was associated with a higher risk of relapse in patients allografted for myeloid malignancies. Prospective studies on VitD status and correction of VitD deficiency in the setting of alloSCT are highly warranted.

EASIX in patients with acute graft-versus-host disease: a retrospective cohort analysis

BACKGROUND

Endothelial dysfunction links thrombotic microangiopathy to steroid-refractory graft-versus-host disease (GVHD) after allogeneic stem-cell transplantation. We aimed to assess if the simple formula-lactate dehydrogenase (U/L) × creatinine (mg/dL)/thrombocytes (10⁹ cells per L)-termed the Endothelial Activation and Stress Index (EASIX), might be valuable for the prediction of death in patients with acute GVHD after allogeneic stem-cell transplantation.

METHODS

For this retrospective analysis, we analysed a training cohort (in Germany) and three validation cohorts (in Germany and the USA) of patients with acute GVHD who had received consecutive allogeneic stem-cell transplantation. The primary endpoint was prediction of overall survival when measured at acute GVHD onset (EASIX-GVHD). We validated the prognostic strength of EASIX-GVHD for overall survival and non-relapse mortality in the three independent cohorts by calculating the prediction error (integrated Brier score), and concordance index.

FINDINGS

In the total cohort of patients with acute GVHD (n=311), EASIX-GVHD predicted overall survival in univariable and multivariable models (univariate analysis, hazard ratio [HR] for a one-fold increase 1·16, 95% CI 1·12-1·20, p=0·0004). However, in the subpopulation of patients with myeloablative conditioning (n=72), EASIX-GVHD did not predict overall survival, which is probably attributable to thrombocytopenia at GVHD onset (73 × 10⁹ cells per L [IQR 29·75-180·00] for myeloablative conditioning vs 160 × 10⁹ cells per L [90·0-250·5] for reduced-intensity conditioning; p<0·0001). In patients who received reduced-intensity conditioning (n=239), EASIX-GVHD was a strong predictor of overall survival (HR for a two-fold change of 1·23, 95% CI 1·13-1·34; p<0·0001) and non-relapse mortality (cause-specific HR for a two-fold change of 1·24, 1·12-1·38; p<0·0001). Model validation for prediction of overall survival and non-relapse mortality by EASIX-GVHD was successful in two independent cohorts of adult patients with reduced-intensity conditioning (n=141, n=173) and in a cohort with mainly paediatric patients (n=89).

INTERPRETATION

In patients with reduced-intensity conditioning, EASIX-GVHD is a powerful predictor of survival after GVHD. EASIX-GVHD could be the future basis for development of risk-adapted GVHD treatment strategies.

FUNDING

There was no external funding source for this study.

Transplant-associated thrombotic microangiopathy is an endothelial complication associated with refractoriness of acute GvHD

There is increasing evidence that endothelial dysfunction is involved in refractoriness of acute GvHD (aGvHD). Here we investigated the hypothesis that another endothelial complication, transplant-associated thrombotic microangiopathy (TMA), contributes to the pathogenesis of aGvHD refractoriness. TMA was retrospectively assessed in 771 patients after allogeneic stem cell transplantation (alloSCT). Incidences of TMA and refractory aGvHD were correlated with biomarkers of endothelial damage obtained before alloSCT for patients receiving or not receiving statin-based endothelial prophylaxis (SEP). Diagnostic criteria for TMA and refractory aGvHD were met by 41 (5.3%) and 76 (10%) patients, respectively. TMA was overrepresented in patients with refractory aGvHD (45.0 vs 2.3% in all other patients, P<0.001). TMA independently increased mortality. Elevated pretransplant suppressor of tumorigenicity-2 and nitrates along with high-risk variants of the thrombomodulin gene were associated with increased risk of TMA. In contrast, SEP abolished the unfavorable outcome predicted by pretransplant biomarkers on TMA risk. Patients on SEP had a significantly lower risk of TMA (P=0.001) and refractory aGvHD (P=0.055) in a multivariate multistate model. Our data provide evidence that TMA contributes to the pathogenesis of aGvHD refractoriness. Patients with an increased TMA risk can be identified pretransplant and may benefit from pharmacological endothelium protection.

Serum Cotinine Does Not Predict Neutralizing Antibodies Against Interferon Beta in an Austrian MS Cohort

Previous epidemiologic studies showed an increased risk of neutralizing antibody (NAb) development against Interferon beta in multiple sclerosis patients who smoke. Cotinine is an easily detectable metabolite of nicotine and, therefore, can be used as an objective surrogate marker for smoking status. We measured cotinine levels in NAb-positive and NAb-negative patients to find a potential association of nicotine consumption and NAb development. Cotinine was measured in 37 patients with known smoking status and in 123 patients with unknown smoking status, all of whom were routinely tested for NAb. Cotinine was detected by an enzyme-linked immunosorbent assay, inhibition assay. We compared cotinine levels by NAb status and tested for the strength of association between cotinine and NAb status. We found a discrepancy between smoking status stated by patients and status defined by cotinine levels in 7 of 37 patients. In both cohorts, together with and without previously known smoking status (n = 160), we found 34% and 39% smokers, respectively, as defined by cotinine levels in NAb-negative and NAb-positive patients (P = 0.511). In our analysis, smoking was not associated with higher risk of NAb development. Moreover, smoking habits stated by patients do not always correlate with cotinine levels.

Clinical activity of azacitidine in patients who relapse after allogeneic stem cell transplantation for acute myeloid leukemia

Disease relapse is the most common cause of treatment failure after allogeneic stem cell transplantation for acute myeloid leukemia and myelodysplastic syndromes, yet treatment options for such patients remain extremely limited. Azacitidine is an important new therapy in high-risk myelodysplastic syndromes and acute myeloid leukemia but its role in patients who relapse post allograft has not been defined. We studied the tolerability and activity of azacitidine in 181 patients who relapsed after an allograft for acute myeloid leukemia (n=116) or myelodysplastic syndromes (n=65). Sixty-nine patients received additional donor lymphocyte infusions. Forty-six of 157 (25%) assessable patients responded to azacitidine therapy: 24 (15%) achieved a complete remission and 22 a partial remission. Response rates were higher in patients transplanted in complete remission (P=0.04) and those transplanted for myelodysplastic syndromes (P=0.023). In patients who achieved a complete remission, the 2-year overall survival was 48% versus 12% for the whole population. Overall survival was determined by time to relapse post transplant more than six months (P=0.001) and percentage of blasts in the bone marrow at time of relapse (P=0.01). The concurrent administration of donor lymphocyte infusion did not improve either response rates or overall survival in patients treated with azacitidine. An azacitidine relapse prognostic score was developed which predicted 2-year overall survival ranging from 3%-37% (P=0.00001). We conclude that azacitidine represents an important new therapy in selected patients with acute myeloid leukemia/myelodysplastic syndromes who relapse after allogeneic stem cell transplantation. Prospective studies to confirm optimal treatment options in this challenging patient population are required.

Low serum vitamin D levels are associated with shorter survival after first-line azacitidine treatment in patients with myelodysplastic syndrome and secondary oligoblastic acute myeloid leukemia

BACKGROUND & AIMS

Azacitidine (AZA) therapy has become the recommended first-line treatment for patients with high-risk myelodysplastic syndromes (MDS) and oligoblastic (<30% bone marrow blasts) acute myeloid leukemia (AML). However, improvement of the efficacy of AZA treatment remains a challenge. We retrospectively tested the hypothesis that VitD levels (25-hydroxyvitamin D3) prior to start of first-line AZA therapy are predictive of overall survival (OS) in patients diagnosed with MDS and secondary oligoblastic AML. Furthermore, the antiproliferative effects of AZA in combination with 25-hydroxyvitamin D3 and 1α,25-dihydroxyvitamin D3 were investigated in vitro.

METHODS

A total of 58 patients treated at our center between 2006 and 2014 were analyzed. Serum levels of VitD were quantified using a standard, commercially available 25-hydroxyvitamin D3 chemiluminescent immunoassay. Effects on cell proliferation were assessed using tetrazolium-based MTT assays.

RESULTS

Median serum VitD level prior to AZA treatment was 32.8 nM (range 11.0-101.5 nM). Patient, disease and treatment characteristics did not differ significantly between the low (≤32.8 nM; n = 29) and high (>32.8 nM; n = 29) VitD group. Estimated probability of 2-year OS in the low versus high VitD group was 14% versus 40% (P < 0.05). In multivariable analysis with OS as endpoint, adverse cytogenetics (HR 2.66, P = 0.03) and VitD (per 10 nM decrease, HR 1.68, P = 0.02) were independent predictors of worse survival. In-vitro treatment of myeloid cell lines with AZA in combination with VitD produced synergistic and additive antiproliferative effects. Addition of nanomolar VitD concentrations to AZA resulted in potentiation of AZA activity. Conversely, combination with the VitD antagonist TEI-9647 resulted in inhibition of AZA activity.

CONCLUSIONS

Our study suggests that higher VitD levels were associated with a survival advantage following first-line AZA therapy. Enhanced cytotoxic effects upon combination treatment may contribute to the observed clinical effects. VitD repletion/supplementation during AZA treatment should be explored.