Chronic graft-versus-host disease detected by tissue-specific cell-free DNA methylation biomarkers.

BACKGROUND: Accurate detection of graft-versus-host disease (GVHD) is a major challenge in the management of patients undergoing hematopoietic stem cell transplantation (HCT). Here, we demonstrated the use of circulating cell-free DNA (cfDNA) for detection of tissue turnover and chronic GVHD (cGVHD) in specific organs. METHODS: We established a cocktail of tissue-specific DNA methylation markers and used it to determine the concentration of cfDNA molecules derived from the liver, skin, lungs, colon, and specific immune cells in 101 patients undergoing HCT. RESULTS: Patients with active cGVHD showed elevated concentrations of cfDNA, as well as tissue-specific methylation markers that agreed with clinical scores. Strikingly, transplanted patients with no clinical symptoms had abnormally high levels of tissue-specific markers, suggesting hidden tissue turnover even in the absence of evident clinical pathology. An integrative model taking into account total cfDNA concentration, monocyte/macrophage cfDNA levels and alanine transaminase was able to correctly identify GVHD with a specificity of 86% and precision of 89% (AUC of 0.8). CONCLUSION: cfDNA markers can be used for the detection of cGVHD, opening a window into underlying tissue dynamics in patients that receive allogeneic stem cell transplants. FUNDING: This work was supported by grants from the Ernest and Bonnie Beutler Research Program of Excellence in Genomic Medicine, The Israel Science Foundation, the Waldholtz/Pakula family, the Robert M. and Marilyn Sternberg Family Charitable Foundation and the Helmsley Charitable Trust (to YD).

Mesenchymal Stromal Cell-Derived Small Extracellular Vesicles Modulate Apoptosis, TNF Alpha and Interferon Gamma Response Gene mRNA Expression in T Lymphocytes.

Recent studies have highlighted the therapeutic potential of small extracellular bodies derived from mesenchymal stem cells (MSC-sEVs) for various diseases, notably through their ability to alter T-cell differentiation and function. The current study aimed to explore immunomodulatory pathway alterations within T cells through mRNA sequencing of activated T cells cocultured with bone marrow-derived MSC-sEVs. mRNA profiling of activated human T cells cocultured with MSC-sEVs or vehicle control was performed using the QIAGEN Illumina sequencing platform. Pathway networks and biological functions of the differentially expressed genes were analyzed using Ingenuity pathway analysis (IPA)® software, KEGG pathway, GSEA and STRING database. A total of 364 differentially expressed genes were identified in sEV-treated T cells. Canonical pathway analysis highlighted the RhoA signaling pathway. Cellular development, movement, growth and proliferation, cell-to-cell interaction and inflammatory response-related gene expression were altered. KEGG enrichment pathway analysis underscored the apoptosis pathway. GSEA identified enrichment in downregulated genes associated with TNF alpha and interferon gamma response, and upregulated genes related to apoptosis and migration of lymphocytes and T-cell differentiation gene sets. Our findings provide valuable insights into the mechanisms by which MSC-sEVs implement immunomodulatory effects on activated T cells. These findings may contribute to the development of MSC-sEV-based therapies.

Tumor-infiltrating lymphocyte transfusion in a patient with treatment refractory triple negative breast cancer.

BACKGROUND: Triple negative breast cancer (TNBC) is an aggressive form of breast cancer that is treated with chemotherapy. Recently, programmed death 1 (PD1) inhibition, as well as antibody-drug conjugates, have been added to the available treatment regimen, yet metastatic disease is fatal. Adoptive cell therapy (ACT) using tumor infiltrating lymphocytes (TILs) has been well described in melanoma, but less data is available on other solid malignancies. CASE: Herein, we present a case of a 31-year-old patient diagnosed with Breast Cancer gene 1 (BRCA1) positive, TNBC. The patient's disease rapidly progressed while under standard treatment protocols. As a result, additional genetic testing of the tumor was carried out and revealed loss of BRCA1 heterozygosity, a double Tumor Protein 53 (TP53) mutation, and MYC amplification. Due to resistance to conventional therapy, an experimental approach was attempted using tumor-infiltrating lymphocytes in November 2021 at Hadassah University Medical Center. While receiving this treatment, the patient exhibited a reported subjective clinical improvement including a month spent out of the hospital. However, the final result, presumably due to Interleukin 2 (IL-2) toxicity, was the patient's passing. CONCLUSION: This case is unique and peculiar regarding the treatment modality chosen, due to the extremely refractory disease the patient suffered from. After standard therapies rapidly failed, adoptive cell therapy was attempted with the infusion of TILs. This treatment has been shown effective in melanoma, however, there is an extreme paucity of data on other solid tumors, including TNBC. Although the patient ultimately demised presumably due to treatment side effects, brief clinical benefit was apparent. Further studies are warranted.

High rate of adenovirus detection in gastrointestinal biopsies of symptomatic stem cell transplant recipients.

OBJECTIVES: The gastrointestinal (GI) tract is a major human adenovirus (HAdV) replication site in patients undergoing hematopoietic stem cell transplantation (HSCT), yet the prevalence and correlates of HAdV GI infection in this setting have remained poorly recognized, especially among adult HSCT recipients. DESIGN OR METHODS: We retrospectively studied the prevalence and risk factors of HAdV GI-tissue infection in HSCT recipients (73 adults and 15 children) with GI symptoms who underwent GI-tissue biopsy between January-2012 and December-2017. The presence of HAdV in the GI tissues was determined by real-time PCR. RESULTS: HAdV GI-tissue infection was detected in 21 (23.9%) patients, with similar infection rates identified in adults and children. GI-tissue detection was more common at late (>100 days) compared to early times post-transplantation (50% vs. 12.9%, p < .001). The presence of bloody diarrhea, Arab ethnicity (p = .014) and concurrent cytomegalovirus GI-tissue detection (p = .025) were significantly correlated with HAdV GI-tissue infection, while chronic graft versus host disease was of borderline association (p = .055). CONCLUSIONS: Our findings reveal a high rate and new clinical-demographic correlates of HAdV GI-tissue infection in adult and pediatric HSCT recipients with GI symptoms. The findings highlight the need for future prospective studies to assess the relatedness of HAdV infection to the GI symptoms, and the prevalence, impact, and treatment of HAdV GI infection in HSCT recipients.

Placental expanded mesenchymal-like cells (PLX-R18) for poor graft function after hematopoietic cell transplantation: A phase I study.

Persistent cytopenia in the post-hematopoietic cell transplantation (HCT) setting can occur despite adequate engraftment of donor cells. PLX-R18, a placental-derived mesenchymal-like cell product, is expanded ex vivo in a 3-dimensional environment. PLX-R18 cells secrete a large array of hematopoietic factors, which promote regeneration, maturation, and differentiation of hematopoietic cells and stimulate their migration to peripheral blood. This phase 1, first-in-human study (NCT03002519), included 21 patients with incomplete hematopoietic recovery post-HCT. Patients were treated with escalating doses of PLX-R18: 3 patients received 1 million cells/kg, 6 received 2 million cells/kg, and 12 received 4 million cells/kg via multiple intramuscular injections. While patients received only two administrations of cells during the first week, peripheral blood counts continued to increase for months, peaking at 6 months for hemoglobin (Hb, p = 0.002), lymphocytes (p = 0.008), and neutrophils (ANC, p = 0.063), and at 9 months for platelets (p < 0.001) and was maintained until 12 months for all but ANC. The need for platelet transfusions was reduced from 5.09 units/month at baseline to 0.55 at month 12 (p = 0.05). Likewise, red blood cell transfusions decreased from 2.91 units/month at baseline to 0 at month 12 (p = 0.0005). PLX-R18 was safe and well tolerated and shows promise in improving incomplete hematopoietic recovery post-HCT.

Clonal Myeloid Dysplasia Following CAR T-Cell Therapy: Chicken or the Egg?

Multiple myeloma (MM) is characterized by recurrent relapses. Consequently, patients receive multiple therapy lines, including alkylating agents and immune modulators, which have been associated with secondary malignancies such as myelodysplastic syndrome (MDS). Anti-B-cell maturation antigen (BCMA) chimeric antigen receptor T cell (CART) therapy is efficacious in patients with relapsed/refractory (R/R) MM. However, the long-term complications, particularly MDS, are not well understood. Whether CART therapy causes or promotes MDS has not been thoroughly investigated. In this study, we explored the causal relationship between MDS and CART therapy. We retrospectively examined the prevalence of MDS-related morphological and mutational changes before and after administration of CART therapy in five patients. Among them, four developed MDS after CART therapy, while one had pre-existing MDS prior to CART. None of the four patients who developed post-CART MDS showed morphological MDS changes prior to CART therapy. However, all four patients exhibited molecular alterations associated with MDS in their pre-CART as well as post-CART therapy bone marrow. No new mutations were observed. Our findings provide initial evidence suggesting that anti-BCMA CART therapy in MM may promote expansion of pre-existing MDS clones rather than causing development of new clones.

Long-Term Results with Thiotepa-Containing Conditioning Regimens for Autologous Stem Cell Transplantation.

Autologous stem cell transplantation (ASCT) remains a cornerstone in the treatment of both Hodgkin lymphoma (HL) and various non-Hodgkin lymphoma (NHL) subtypes. BEAM (carmustine, etoposide, cytarabine, and melphalan) is the most frequently used conditioning regimen; however, owing due to limited availability and toxicity of carmustine, thiotepa-containing regimens have been suggested. We previously reported encouraging results in ASCT with a TECAM (thiotepa, etoposide, cyclophosphamide, cytarabine, and melphalan) conditioning regimen from 2000 to 2013. We aimed to update our experience with the TECAM regimen by adding our experience from 2013 to 2020 to the previously reported cohort. Moreover, we aimed to use the detailed data for the 2 transplant cohorts to identify improvements in ASCT outcomes in the recent era. We retrospectively analyzed all lymphoma patients who underwent ASCT at our center between January 2000 and December 2020. A total of 353 lymphoma patients were included (142 in the newer cohort added to 211 previously reported patients), all of whom were treated with our standard TECAM conditioning regimen. The cohort included 127 patients with HL, 107 with DLBCL, and 119 with other NHL subtypes. The newer cohort was characterized by significantly poorer Eastern Cooperative Oncology Group Performance Status (ECOG-PS) prior to ASCT (45.7% versus 19.3% with ECOG-PS ≥1; P < .01), whereas a higher proportion of patients entered transplantation in complete response (CR) (71.9% versus 47.8%; P < .01). The median follow-up after ASCT was 136.4 months (95% confidence interval [CI], 91.4 to 181.4 months). The 3-year progression-free survival (PFS) and overall survival (OS) rates post-ASCT for the entire cohort were 59.8% and 79.3%, respectively. Evaluating the 303 of 353 patients (86.4%) who entered ASCT with a responsive disease-a population that represents today's approach to the selection of patients for ASCT-the 3-year PFS and OS rates were 61.5% and 81.9%, respectively. In this population, the 3-year PFS rate was 62.2% for HL, 62.6% for DLBCL, 64.3% for primary central nervous system lymphoma (PCNSL), and the 3-year OS rate were 90.1%, 75.2%, and 78.6%, respectively. OS was significantly better in the newer cohort (P < .01), but not when evaluating only patients who entered ASCT with responsive disease. Dose reductions, poor disease status, and poor ECOG-PS at ASCT entry were associated with worse outcomes across all lymphoma subtypes. In accordance with our previous report, patients entering transplantation for DLBCL with a partial response achieved similar outcomes as those with a CR. Eighteen patients died within the first 100 days, 8 due to disease progression and 10 due to transplantation-related complications (2.8%). There were no cases of interstitial pneumonitis syndrome. Twenty-two cases (6.2%) of secondary malignancies were documented. Our results confirm that TECAM is an effective and safe conditioning regimen for ASCT in patients with HL and various NHLs, including favorable results in PCNSL. Despite a higher proportion of frail patients, the newer cohort's outcomes were favorable, driven by better lymphoma control pretransplantation. In the DLBCL cohort, ECOG-PS had more prognostic value than achieving a CR pre-ASCT, a finding relevant to the optimal allocation of patients to different treatment options in the era of chimeric antigen receptor T cell availability.

The DNA methylome of human vascular endothelium and its use in liquid biopsies.

BACKGROUND: Vascular endothelial cells (VECs) are an essential component of each tissue, contribute to multiple pathologies, and are targeted by important drugs. Yet, there is a shortage of biomarkers to assess VEC turnover. METHODS: To develop DNA methylation-based liquid biopsies for VECs, we determined the methylome of VECs isolated from freshly dissociated human tissues. FINDINGS: A comparison with a human cell-type methylome atlas yielded thousands of loci that are uniquely unmethylated in VECs. These sites are typically gene enhancers, often residing adjacent to VEC-specific genes. We also identified hundreds of genomic loci that are differentially methylated in organotypic VECs, indicating that VECs feeding specific organs are distinct cell types with a stable epigenetic identity. We established universal and lung-specific VEC markers and evaluated their presence in circulating cell-free DNA (cfDNA). Nearly 2.5% of cfDNA in the plasma of healthy individuals originates from VECs. Sepsis, graft versus host disease, and cardiac catheterization are associated with elevated levels of VEC-derived cfDNA, indicative of vascular damage. Lung-specific VEC cfDNA is selectively elevated in patients with chronic obstructive pulmonary disease (COPD) or lung cancer, revealing tissue-specific vascular turnover. CONCLUSIONS: VEC cfDNA biomarkers inform vascular dynamics in health and disease, potentially contributing to early diagnosis and monitoring of pathologies, and assessment of drug activity. FUNDING: This work was supported by the Beutler Research Program, Helmsley Charitable Trust, JDRF, Grail and the DON Foundation (to Y.D.). Y.D holds the Walter & Greta Stiel Chair in heart studies. B.G., R.S., J.M., D.N., T.K., and Y.D. filed patents on cfDNA analysis.

Third BNT162b2 mRNA SARS-CoV-2 Vaccine Dose Significantly Enhances Immunogenicity in Recipients of Allogeneic Hematopoietic Stem Cell Transplantation.

COVID-19-related mortality among hematopoietic stem cell transplantation (HSCT) recipients in the pre-vaccine era ranged between 22 and 33%. The Pfizer/BioNTech BNT162b2 vaccine demonstrated significant immunogenicity and efficacy in the healthy population; however, its long-term effects on allogeneic HSCT recipients remained unclear. Our study longitudinally evaluated humoral and cellular responses to the BNT162b2 vaccine in adult allogeneic HSCT patients. A positive response was defined as antibody titers ≥ 150 AU/mL post-second vaccination. Among 77 included patients, 51 (66.2%) responded to vaccination. Response-associated factors were female gender, recent anti-CD20 therapy, and a longer interval between transplant and vaccination. Response rates reached 83.7% in patients vaccinated >12 months post-transplant. At 6 months post-second vaccination, antibody titers dropped, but were significantly increased with the booster dose. Moreover, 43% (6/14) of non-responders to the second vaccination acquired sufficient antibody titers after booster administration, resulting in an overall response rate of 79.5% for the entire cohort. The BNT162b2 vaccine was effective in allogeneic transplant recipients. Although antibody titers decreased with time, the third vaccination led to their significant elevation, with 93% of third-dose responders maintaining titers above 150 AU/mL at 3 months post-administration.

Risk factors and outcomes of COVID-19 in adult patients with hematological malignancies: A single-center study showing lower than expected rates of hospitalization and mortality.

BACKGROUND: Studies addressing coronavirus disease 2019 (COVID-19) in patients with hematological malignancies have reported mortality rates of up to 40%; however, included predominantly hospitalized patients. METHODS: During the first year of the pandemic, we followed adult patients with hematological malignancies treated at a tertiary center in Jerusalem, Israel, who contracted COVID-19, with the aim of studying risk factors for adverse COVID-19-related outcomes. We used remote communication to track patients managed at home-isolation, and patient questioning to assess the source of COVID-19 infection, community versus nosocomial. RESULTS: Our series included 183 patients, median age was 62.5 years, 72% had at least one comorbidity and 39% were receiving active antineoplastic treatment. Hospitalization, critical COVID-19, and mortality rates were 32%, 12.6%, and 9.8%, respectively, remarkably lower than previously reported. Age, multiple comorbidities, and active antineoplastic treatment were significantly associated with hospitalization due to COVID-19. Treatment with monoclonal antibodies was strongly associated with both hospitalization and critical COVID-19. In older (≥60) patients not receiving active antineoplastic treatment, mortality, and severe COVID-19 rates were comparable to those of the general Israeli population. We did not detect patients that contracted COVID-19 within the Hematology Division. CONCLUSION: These findings are relevant for the future management of patients with hematological malignancies in COVID-19-affected regions.

Response rates of extra-nodal diffuse large B cell lymphoma to anti-CD19-CAR T cells: A real word retrospective multicenter study.

Chimeric antigen receptor T-cells (CAR-T) are widely used for the treatment of relapsed/refractory diffuse large B cell lymphoma (DLBCL). The data for CAR-T cell therapy in patients with extra-nodal (EN) lymphoma is restricted. We included 126 consecutive patients with DLBCL treated with commercially available CAR-T cells (tisagenlecleucel, n = 100, 79.4% and axicabtagene ciloleucel, n = 26, 20.6%). At lymphodepletion, 72 of 126 (57%) patients had EN disease, 42 of 126 (33%) patients had nodal disease (ND)-only and 12 of 126 (10%) showed no disease assessed by PET-CT. There were no significant differences in CAR-T related toxicities and in the median Progression free survival (PFS) between EN patients and ND (10.76 [95% CI: 7.8-13.6] vs. 14.1 [95% CI: 10-18.1] months, p = .126). Similarly, median overall survival (OS) was not significantly different (15.36 [95% CI 12.5-18.2] vs. 18.4 [95% CI 14.8-22.1] months, p = .100). Subgroup analysis according to the number of EN involved sites showed that median PFS and OS were significantly higher in patients with <3 EN sites (12.3 months [95% CI 9-15.5] vs. 4.28 months [95% CI 0.6-7.9], p = .010) compared to patients with >2 EN sites, respectively (16.5 months [95% CI 13.4-19.6] vs. 8.7 months [95% CI 4.6-12.8], p = .05). In multivariate cox regression analysis, increased number sites of EN disease and high lactate dehydrogenase (LDH) at lymphodepletion negatively impacted PFS (p = .021 and <.001, respectively), while sex, type of product administered, age and performance status did not predict PFS and OS. Of note, all the patients with involvement of gastrointestinal tract (n = 9), urinary tract (n = 9), or pharynx (n = 3) at lymphodepletion, progressed or had an early relapse. In conclusions, patients with >2 EN sites at lymphodepletion have significantly worse clinical outcomes compared to patients with <3 EN sites. Patients with specific sites of EN disease may demonstrate grim prognosis.

[STEM CELL TRANSPLANTATIONS FOR PATIENTS WITH FANCONI ANEMIA: AN ISRAELI TERTIARY CENTER EXPERIENCE].

INTRODUCTION: Fanconi anemia (FA) is a rare genetic syndrome characterized by increased chromosomal breakage, congenital anomalies, bone marrow failure and an increased tendency to develop malignancies. Allogeneic hematopoietic stem cell transplantation (HSCT) is the only curative treatment for bone marrow failure and the hematologic malignancies these patients develop. Given the sensitivity of FA patients to chemotherapy and radiation, as to the clinical symptoms of graft versus host disease (GvHD), HSCT in these patients is challenging. Since the mid-nineties, HSCT for FA patients is performed in our center by using the fludarabine based reduced-intensity protocol. AIMS: To summarize the results of HSCT for patients with FA using a fludarabine based reduced-intensity conditioning regimen at the Hadassah Medical Center. METHODS: This retrospective research is based on the collection and analysis of clinical and laboratory data from the medical records of patients. RESULTS: Since June 1996 up till February 2020, 39 patients with FA underwent 43 HSCTs with a fludarabine based protocol at the Hadassah Medical Center. Four patients required a second transplant due to primary engraftment failure. Nine patients (23%) suffered from acute GvHD, four of them severe. Eight patients (20%) developed chronic GvHD, two with an extensive and debilitating disease. Thirty-three (85%) of the patients survived and six died, five shortly after the transplant, and one twenty years later from malignancy. CONCLUSIONS: Our results show high survival rates with low rates of engraftment failure and reasonable rates of GvHD. DISCUSSION: As of today, there is an effective and safe treatment for patients with FA who require HSCT by using a fludarabine-based reduced-intensity conditioning regimen, with high survival rates and few complications.

Two decades of stem cell transplantation in patients with Fanconi anemia: Analysis of factors affecting transplant outcomes.

Allogeneic hematopoietic stem cell transplantation (HSCT) is currently the only curative treatment for the hematological complications of patients with Fanconi anemia (FA). Over the last two decades, HSCT outcomes have improved dramatically following the development of regimens tailored for FA patients. In this study, we analyzed genetic, clinical, and transplant data of 41 patients with FA who underwent HSCT at Hadassah Medical Center between November 1996 and September 2020. Overall survival (OS) was 82.9% with a median follow-up time of 2.11-years (95% CI, .48-16.56). Thirteen patients (31.7%) developed acute graft-versus-host disease (GVHD), three of them with grades 3-4. Nine patients developed chronic GVHD, five had extensive disease. Twelve patients (29.3%) developed stable mixed-chimerism with complete resolution of bone marrow failure (BMF); none of them had acute nor chronic GVHD. Significantly higher GVHD rates were observed in transplants from peripheral blood stem cell grafts as compared to other stem cell sources (p = .002 for acute and p = .004 for chronic GVHD). Outcome parameters were comparable between HSCT from matched-sibling (n = 20) to other donors (n = 21), including survival rates (p = .1), time to engraftment (p = .69 and p = .14 for neutrophil and platelet engraftment time, respectively), chimerism status (p = .36 and p = .83 for full-donor and mixed chimerism, respectively), and GVHD prevalence (p = 1). Our results demonstrate the vast improvements in HSCT outcomes of patients with FA, narrowing the gap between matched-sibling versus alternative donor transplantations. Our data identifies factors that may significantly affect transplant outcomes such as graft source and chimerism status.

Development and manufacture of novel locally produced anti-BCMA CAR T cells for the treatment of relapsed/refractory multiple myeloma: results from a phase I clinical trial.

Anti-B-cell maturation antigen (BCMA) chimeric antigen receptor T-cell (CAR T) therapy shows remarkable efficacy in patients with relapsed and/or refractory (R/R) multiple myeloma (MM). HBI0101, a novel second generation optimized anti- BCMA CAR T-cell therapy, was developed in an academic setting. We conducted a phase I dose-escalation study of HBI0101 (cohort 1: 150x106 CAR T cells, n=6; cohort 2: 450x106 CAR T cells, n=7; cohort 3: 800x106 CAR T cells, n=7) in 20 heavily pre-treated R/R MM patients. Grade 1-2 cytokine release syndrome (CRS) was reported in 18 patients (90%). Neither grade 3-4 CRS nor neurotoxicity of any grade were observed. No dose-limiting toxicities were observed in any cohort. The overall response rate (ORR), (stringent) complete response (CR/sCR), and very good partial response rates were 75%, 50%, and 25%, respectively. Response rates were dose-dependent with 85% ORR, 71% CR, and 57% minimal residual disease negativity in the high-dose cohort 3. Across all cohorts, the median overall survival (OS) was 308 days (range 25-466+), with an estimated OS of 55% as of June 27th (data cut-off). The median progression-free survival was 160 days, with 6 subjects remaining progression free at the time of data cut-off. Our findings demonstrate the manageable safety profile and efficacy of HBI0101. These encouraging data support the decentralization of CAR T production in an academic setting, ensuring sufficient CAR T supply to satisfy the increasing local demand. Clinicaltrials.gov NCT04720313.

Altered Serum Alpha1-Antitrypsin Protease Inhibition before and after Clinical Hematopoietic Stem Cell Transplantation: Association with Risk for Non-Relapse Mortality.

α1-Antitrypsin (AAT), an acute-phase reactant not unsimilar to C-reactive protein (CRP), is a serine protease inhibitor that harbors tissue-protective and immunomodulatory attributes. Its concentrations appropriately increase during conditions of extensive tissue injury, and it induces immune tolerance, in part, by inhibiting the enzymatic activity of the inflammatory serine protease, proteinase 3 (PR3). Typically administered to patients with genetic AAT deficiency, AAT treatment was recently shown to improve outcomes in patients with steroid-refractory graft-versus-host disease (GVHD). GVHD represents a grave outcome of allogeneic hematopoietic stem cell transplantation (HSCT), a potentially curative intervention for hematological diseases. The procedure requires radio/chemotherapy conditioning of the prospective marrow recipient, a cytotoxic process that causes vast tissue injury and, in some formats, interferes with liver production of AAT. To date, changes in the functional profile of AAT during allogeneic HSCT, and during the cytotoxic intervention that precedes HSCT, are unknown. The present study followed 53 patients scheduled for allogeneic HSCT (trial registration NCT03188601). Serum samples were tested before and after HSCT for AAT and CRP levels and for intrinsic anti-proteolytic activity. The ex vivo response to clinical-grade AAT was tested on circulating patient leukocytes and on a human epithelial cell line treated with patient sera in a gap closure assay. According to the ex vivo experiments, circulating leukocytes responded to AAT with a favorable immune-regulated profile, and epithelial gap closure was enhanced by AAT in sera from GVHD-free patients but not in sera from patients who developed GVHD. According to serum collected prior to HSCT, non-relapse mortality was reliably predicted by combining three components: AAT and CRP levels and serum anti-proteolytic activity. Taken together, HSCT outcomes are significantly affected by the anti-proteolytic function of circulating AAT, supporting early AAT augmentation therapy for allogeneic HSCT patients.

Feasibility of a Novel Academic BCMA-CART (HBI0101) for the Treatment of Relapsed and Refractory AL Amyloidosis.

PURPOSE: AL amyloidosis (AL) treatments are generally based on those employed for multiple myeloma. Anti-B-cell maturation antigen (BCMA) chimeric antigen receptor T (CART)-cell therapy, already approved for multiple myeloma, might be too toxic for patients with AL. EXPERIMENTAL DESIGN: Here we describe the ex vivo applicability of a novel in-house, academic anti-BCMA CAR construct on AL primary cells, as well as the safety and efficacy in 4 patients with relapsed/refractory (RR) primary AL, treated in a phase I clinical trial (NCT04720313). RESULTS: Three had MAYO stage IIIa cardiac involvement at enrollment. The treatment proved relatively safe, with a short and manageable grade 3 cytokine release syndrome evident in 2 patients and no neurotoxicity in any. Cardiac decompensations, observed in 2 patients, were also short and manageable. The overall hematologic response and complete response rates were observed in all patients with an organ response evident in all four. Within a median follow-up period of 5.2 (2.5-9.5) months, all 4 patients maintained their responses. CONCLUSIONS: BCMA-CART cells provide a first proof-of-concept that this therapy is safe enough and highly efficacious for the treatment of patients with advanced, RR AL.

Monitoring Minimal Residual Disease in RUNX1-Mutated Acute Myeloid Leukemia.

INTRODUCTION: Mutated RUNX1 is considered a poor prognostic factor and usually is mutually exclusive with NPM1 mutations. Monitoring of molecular markers for minimal residual disease provides a powerful tool to assess remission and guide clinical decisions. METHODS: Newly diagnosed RUNX1-mutated AML patients, designated to intensive chemotherapy-based treatment or nonintensive regimens, were monitored for mutated RUNX1 transcript levels by qPCR with patient-specific primers. Samples were obtained along the treatment course and follow-up. RESULTS: A clear correlation was observed between mutated RUNX1 levels and response to treatment as observed by flow cytometry and STR-based assessment. CONCLUSION: We demonstrate the feasibility of RUNX1-based MRD to correlate with the clinicopathological status of leukemia. We further suggest how RUNX1 qPCR monitoring can influence clinical decision-making and contribute to improved personalized patient care.

Mesenchymal stroma/stem cells: Haematologists' friend or foe?

Mesenchymal stromal cells (MSCs) are non-haematopoietic cells found in fetal and adult organs, that play important roles in tissue repair, inflammation and immune modulation. MSCs residing in the bone marrow interact closely with haematopoietic cells and comprise an important component of the microenvironment supporting haematopoiesis, in both health and disease states. Since their identification in 1970, basic scientific and preclinical research efforts have shed light on the role of MSCs in the regulation of haematopoiesis and evoked interest in their clinical application in haematopoietic stem cell transplantation (HSCT) and malignant haematology. Over the last two decades, these research efforts have led to numerous clinical trials, which have established the safety of MSC therapy; however, the optimal mode of administration and the benefit remain inconclusive. In this paper, we will review the clinical experience with use of MSCs in HSCT for enhancement of engraftment, prevention and treatment of graft-versus-host disease and haemorrhagic cystitis. Then, we will discuss the contradictory evidence regarding tumour-promoting versus tumour-suppressing effects of MSCs in haematological malignancies, which may have relevance for future clinical applications.

Rituximab, methotrexate, procarbazine and lomustine (R-MPL) for the treatment of primary Central nervous system lymphoma.

The optimal high-dose methotrexate (HDMTX)-based combination therapy for primary central nervous system lymphoma is unknown. We report our experience with rituximab, HDMTX, procarbazine and lomustine (R-MPL) given as first-line treatment in our center. Fifty-two patients between 2006 and 2019 were included. Eighteen patients proceeded to autologous transplant or two cycles of intermediate-dose cytarabine. The median age was 62 y (range 28-94) and the Eastern Cooperative Oncology Group performance status (ECOG-PS) was ≥2 in 62% (32/52). The overall/complete response rates were 79% (41/52) and 52% (27/52), respectively. The median progression-free/overall survival was 19 m/84m, respectively. Grade 3-4 adverse events included infections (17%) and kidney injury (13%). Ten patients (19%) discontinued therapy for toxicity. There were no treatment-related deaths. In summary, in a cohort enriched in frail patients, R-MPL achieved good responses and OS and was safe for all ages. The PFS was sub-optimal, possibly explained by a low proportion of consolidation. This regimen should be evaluated prospectively.