Celebrating the registration of 9.000 patients treated with CAR T cells in the EBMT registry: Collection of real-world data in the context of hematopoietic cellular therapies.

The European society for Blood and Marrow Transplantation (EBMT) has a long-standing interest in the evaluation of hematopoietic cell transplantation. More than three decades ago, its members established a continental registry. Today, more than 700,000 patients have been registered, and information has been gathered on more than 800,000 transplants. This huge amount of information has allowed conducting multiple retrospective studies, evaluating changes in practices over time and for different categories of diseases, benchmarking outcome across EBMT affiliated centers, and increasingly serves to build synthetic comparators to evaluate the introduction of therapeutic innovations in the field of hematology. CAR-T cells therapies draw on human and technical resources that are also used to deliver HCT; they elicit side effects that require the implementation of risk mitigation plans; they are living drugs that persist in the body of the recipient and thus deserve prolonged follow-up; the introduction of CAR-T cells in the pharmacopeia is likely to significantly impact on the practice of BMT; for all these reasons and even before the first approvals of CAR-T Cells in Europe, EBMT engaged in a project aiming at complementing the EBMT Registry with a Cellular Therapy Form, with the objective to register CAR-T cells treated patients and collect information on their short-, middle- and long-term outcome. The goal is to provide EBMT investigators with a tool for primary analyses of the collected information and to support secondary use of data transferred at the individual level to Marketing Authorization Holders and other interested parties, to fulfill their obligations to health authorities and further evaluate the actual medical values of CAR-T Cells in different contexts and indications. The EBMT Registry received a positive opinion from the European Medicines agency in 2019, and five years later contains information on more than 9.000 treated patients. This article describes the journey to start this new activity, lessons to be drawn in view of improving the collection of real-world data, and what existing information tells us in terms of patient access.

Characteristics of HPC(A) product obtained from a donor with SARS-CoV-2 infection and outcome of autologous transplant.

Collection of hematopoietic progenitor cell products [HPC(A)] is deferred if the donor is symptomatic and tests positive for Covid-19. However, donor questionnaires are subjective and may miss minimally symptomatic donors. Alternatively, myalgia associated with Covid-19 infection can be falsely dismissed as an adverse effect of granulocyte stimulating factor (Filgrastim) administered prior to product collection. The likelihood of donors with an underlying acute but minimally symptomatic infection undergoing successful product collection is significant. In these circumstances, it is less known whether Covid-19 infection results in product viremia or alters the clinical outcome of transplant. We aimed to evaluate the above question by studying a donor whose product was collected during acute Covid-19 infection. Aliquots of the product tested negative for SARS-CoV-2 RNA by reverse-transcriptase polymerase chain reaction assay (RT-PCR). Importantly, the donor received an autologous stem cell transplant using the product collected at the time of infection, and their case will be described in this report. We describe one of the very few reports of successful transplant of HPC(A) product collected during acute Covid-19 infection.

Strong capacity of differentiated PD-L1 CAR-modified UCB-CD34+ cells and PD-L1 CAR-modified UCB-CD34+-derived NK cells in killing target cells and restoration of the anti-tumor function of PD-1-high exhausted T Cells.

BACKGROUND: Using natural killer (NK) cells to treat hematopoietic and solid tumors has great promise. Despite their availability from peripheral blood and cord blood, stem cell-derived NK cells provide an "off-the-shelf" solution. METHODS: In this study, we developed two CAR-NK cells targeting PD-L1 derived from lentiviral transduction of human umbilical cord blood (UCB)-CD34+ cells and UCB-CD34+-derived NK cells. The transduction efficiencies and in vitro cytotoxic functions including degranulation, cytokine production, and cancer cell necrosis of both resultants PD-L1 CAR-NK cells were tested in vitro on two different PD-L1 low and high-expressing solid tumor cell lines. RESULTS: Differentiated CAR­modified UCB-CD34+ cells exhibited enhanced transduction efficiency. The expression of anti-PD-L1 CAR significantly (P < 0.05) enhanced the cytotoxicity of differentiated CAR­modified UCB-CD34+ cells and CAR-modified UCB-CD34+-derived NK cells against PD-L1 high-expressing tumor cell line. In addition, CAR-modified UCB-CD34+-derived NK cells significantly (P < 0.05) restored the tumor-killing ability of exhausted PD-1 high T cells. CONCLUSION: Considering the more efficient transduction in stem cells and the possibility of producing CAR-NK cell products with higher yields, this approach is recommended for studies in the field of CAR-NK cells. Also, a pre-clinical study is now necessary to evaluate the safety and efficacy of these two CAR-NK cells individually and in combination with other therapeutic approaches.

Successful treatment with mesenchymal stem cells for steroid-refractory late-onset idiopathic pneumonia syndrome following allogeneic hematopoietic cell transplantation.

The reportedly poor outcome of late-onset idiopathic pneumonia syndrome (IPS) necessitates new approaches to its treatment. A 55-year-old man who had undergone allogeneic hematopoietic cell transplantation (allo-HCT) for myelodysplastic syndrome 1 year ago developed dyspnea with acute skin graft-versus-host disease (GVHD) flare-up while tapering immunosuppressive agents. He presented with acute respiratory distress syndrome with ground-glass opacities in the right upper and left lower lobes. All infectious tests, including multiplex polymerase chain reaction of nasal wash, were negative, and broad-spectrum antibiotic therapy was refractory. The patient was diagnosed with late-onset IPS and was refractory to methylprednisolone pulse therapy. He then showed a favorable response to mesenchymal stem cell (MSC) infusion. After eight infusions of MSCs, he had no IPS recurrence for over one year. Recently, preclinical studies have reported the potential therapeutic utility of MSC infusion for treating IPS, and our case supports its potential for treating late-onset IPS.

Modified SMILE (mSMILE) is active in the treatment of pediatric Epstein-Barr virus-associated natural killer/T-cell lymphoma: a single center experience, case series.

Background: The Epstein-Barr virus-associated natural killer (NK) and T-cell lymphoma (EBV + NK/T cell lymphoma) is a severe illness mainly affecting children and young adults, often resulting in a poor prognosis. To date, there is no consensus on an established treatment strategy. This study aims to evaluate the efficacy and safety of the mSMILE (modified steroid, methotrexate, ifosfamide, L-asparaginase, and etoposide) chemotherapy regimen in treating EBV+ NK/T-cell lymphoma and to provide insights into potential treatment outcomes. Methods: In this study, we conducted a retrospective analysis of the clinical data and treatment outcomes for patients with EBV + NK/T cell lymphoma treated at Children's Hospital of Nanjing Medical University between July 2017 and January 2022. These patients received at least two cycles of the mSMILE chemotherapy, in which a single dose of pegaspargase was substituted for 7 doses of L-asparaginase per cycle. Results: Eight patients were included in the study: one with extranodal NK/T-cell lymphoma, one with primary nodal NK/T-cell lymphoma, and six with Systemic EBV+ NK/T cell lymphoma of childhood. The results showed that five patients achieved complete remission, two achieved partial remission, and one showed progressive disease, resulting in a complete remission rate of 62.5% and an overall response rate of 87.5%. The 3-year overall survival (OS) and event-free survival (EFS) rates were 87.5% and 75%, respectively. The most common adverse reactions associated with chemotherapy were hematologic toxicities of stages III to IV. Nonhematologic adverse reactions mainly included impaired liver function, infections, and oral mucositis, which were resolved with aggressive anti-infective therapy. Conclusions: Based on our clinical experience, the mSMILE appears to be a safe and effective treatment option for EBV + NK/T-cell lymphoma, meriting further investigation in late-phase clinical trials.

Age and dose dependent changes to the bone and bone marrow microenvironment after cytotoxic conditioning with busulfan.

Preparative regimens before Hematopoietic Cell Transplantation (HCT) damage the bone marrow (BM) microenvironment, potentially leading to secondary morbidity and even mortality. The precise effects of cytotoxic preconditioning on bone and BM remodeling, regeneration, and subsequent hematopoietic recovery over time remain unclear. Moreover, the influence of recipient age and cytotoxic dose have not been fully described. In this study, we longitudinally investigated bone and BM remodeling after busulfan treatment with low intensity (LI) and high intensity (HI) regimens as a function of animal age. As expected, higher donor chimerism was observed in young mice in both LI and HI regimens compared to adult mice. Noticeably in adult mice, significant engraftment was only observed in the HI group. The integrity of the blood-bone marrow barrier in calvarial BM blood vessels was lost after busulfan treatment in the young mice and remained altered even 6 weeks after HCT. In adult mice, the severity of vascular leakage appeared to be dose-dependent, being more pronounced in HI compared to LI recipients. Interestingly, no noticeable change in blood flow velocity was observed following busulfan treatment. Ex vivo imaging of the long bones revealed a reduction in the frequency and an increase in the diameter and density of the blood vessels shortly after treatment, a phenomenon that largely recovered in young mice but persisted in older mice after 6 weeks. Furthermore, analysis of bone remodeling indicated a significant alteration in bone turnover at 6 weeks compared to earlier timepoints in both young and adult mice. Overall, our results reveal new aspects of bone and BM remodeling, as well as hematopoietic recovery, which is dependent on the cytotoxic dose and recipient age.

Plasma concentration of thrombopoietin in dogs with immune thrombocytopenia.

BACKGROUND: Immune thrombocytopenia (ITP) is a common cause of severe thrombocytopenia in dogs. The pathogenesis of nonassociative, primary ITP (pITP) appears complex, with ill-defined thrombopoietic response. OBJECTIVES: Develop an immunoassay to measure plasma canine thrombopoietin (TPO) concentration and characterize TPO concentrations in dogs with pITP. ANIMALS: Forty-one healthy dogs, 8 dogs in an induced ITP model (3 control, 5 ITP), and 58 pITP dogs. METHODS: Recombinant canine TPO (rcTPO) was purchased and its identity confirmed by mass spectrometry. Monoclonal antibodies were raised to rcTPO and used to configure a sandwich ELISA using streptavidin-biotin detection. Assay performance, coefficients of variability, and healthy dog plasma TPO reference interval (RI) were determined, followed by assay of ITP samples. RESULTS: Assay dynamic range was 15 pg/mL (lower limit of detection) to 1000 pg/mL TPO, with limit of quantitation of 62 pg/mL. Plasma TPO RI was 0 to 158 pg/mL, with plasma TPO <62 pg/mL for 35/41 healthy dogs. All dogs with induced ITP developed marked increases in plasma TPO concentration. Peak values ranged from 515 to >6000 pg/mL. In contrast, only 2/58 pITP dogs had TPO values above RI. CONCLUSIONS AND CLINICAL IMPORTANCE: Plasma TPO concentration is paradoxically low at diagnosis for most dogs with pITP. This finding suggests that ineffective thrombopoiesis contributes to thrombocytopenia in pITP dogs and supports evaluating TPO receptor agonist treatment as used for pITP in humans. The TPO assay provides a new tool to study thrombopoiesis in pITP and other thrombocytopenic syndromes in dogs.

Outcomes of older adults undergoing allogeneic hematopoietic cell transplantation with post-transplant cyclophosphamide based prophylaxis.

This study evaluates the feasibility of using post-transplant cyclophosphamide (PTCY) prophylaxis in allo-hematopoietic cell transplantation (HCT) for adults aged 65 and older. PTCY is increasingly used to prevent graft-versus-host disease (GVHD) across all donor types, but concerns remain about potential risks, especially in older patients. Fifty-seven adults aged 65 or older with hematological malignancies, undergoing their first allo-HCT with PTCY prophylaxis between January 2011 and January 2023 were included. Overall, 94.8% of patients achieved primary engraftment. The median durations for neutrophil and platelet engraftments were 19 and 21 days. The day +30 cumulative incidence of bacterial bloodstream infection was 43.9%. No CMV reactivations occurred within the first 100 days after letermovir implementation. The day +180 cumulative incidences of grade II-IV and III-IV acute GVHD, and the 2-year cumulative incidence of moderate/severe chronic GVHD were 26.3%, 10.5%, and 4.8%. Eighteen patients (31.6%) relapsed, and 30 (52.6%) died, with relapse (16.4%) and infection (11.5%) being the main causes of death. The estimated 2-year overall survival, non-relapse mortality, cumulative incidence of relapse, and GVHD-free relapse-free survival rates were 45.5%, 27.1%, 33.9%, and 37.0%. Adults aged 70 or older had similar outcomes to those aged 65-69. This study confirms the safety and feasibility of PTCY-based allo-HCT in older adults.

Severity and organ distribution of graft-versus-host disease with post-transplant cyclophosphamide versus calcineurin inhibitor plus methotrexate/mycophenolate mofetil or sirolimus in allogenic HLA-matched or single-allele mismatched stem cell transplantation.

OBJECTIVE: This retrospective single center study aims to describe changes in the severity and organ-specific distribution of GvHD, by comparing the outcomes of 3 distinct GvHD prophylaxis approaches. METHODS: Between January 2012 and June 2022, 226 patients underwent allogeneic hematopoietic stem cell transplantation from HLA-matched or 1-allele mismatched related or unrelated donors. Fifty-eight (26%) received prophylaxis with calcineurin inhibitor in combination with mycophenolate mofetil or a short course of methotrexate (Cohort-1), 87 (38%) tacrolimus plus sirolimus (Cohort-2), and 81 (36%) post-transplant cyclophosphamide (PTCy) plus tacrolimus (Cohort-3). RESULTS: The incidence of grade II-IV aGvHD was 69% vs. 41.4% vs. 27.2%; p < .01. The most significant reduction with PTCy was observed in both stage 3-4 skin and lower gastrointestinal (GI) involvement (p < .01). The incidence of moderate-to-severe cGvHD at 12 months was 34.5% vs. 34.5% vs. 6.2%; p < .01. Moderate-to-severe skin and GI cGvHD was less common after PTCy (p < .01). The 1-year GvHD-free/relapse-free survival was higher with PTCy (p < .01). CONCLUSIONS: Our study indicates that PTCy-based GvHD prophylaxis reduces the frequency and severity of both acute and chronic GvHD, with a notable decrease in severe GI and cutaneous manifestations. The higher GRFS may result in lower GvHD-related mortality, leading to an improved quality of life among survivors.

Predictors of fluid overload in allogeneic hematopoietic cell transplant patients receiving post-transplant cyclophosphamide.

BACKGROUND: Fluid overload (FO) commonly occurs during hospitalization for allogeneic hematopoietic cell transplantation (HCT). Grade 2-4 FO is associated with day +100 non-relapse mortality.1 Post-transplant cyclophosphamide (PTCY) for graft-versus-host disease prevention requires aggressive IV hydration to prevent hemorrhagic cystitis. MATERIALS AND METHODS: This is a single-center, retrospective, observational study conducted at an academic medical center via electronic chart review. Included patients received allogeneic HCT followed by PTCY on days +3 and +4. Patients were excluded for age < 18 years or incarceration. Primary endpoints are incidence of Grade 2-4 FO and associated risk factors. Descriptive and inferential statistics (i.e., Fisher's exact test, multivariable regression analysis) were used. RESULTS: Of 97 patients screened, 95 were included and 2 were excluded due to absence of weight measurements needed to grade FO. Median age was 60 years, 66.3% were male, 91.6% received reduced-intensity conditioning, 72.6% received haploidentical HCT, 44.2% were ECOG 0, and 11.6% had diastolic dysfunction. Incidence of grade 2-4 FO was 33.7% (n = 32). Univariate analyses found age (continuous; p = 0.04) and BSA < 1.7 m2 (p = 0.006) as independent factors associated with grade 2-4 FO. Multivariable regression analysis found 3.3% higher risk with every 1-year increase in age ranging from f 20 to 78 years (OR 1.033, 95% CI 1.001, 1.006; p = 0.0453) and 82.8% lower risk with BSA ≥ 1.7 m2 (OR 0.172, 95% CI 0.051, 0.588; p = 0.005) after adjusting for co-variates. CONCLUSION(S): Increasing age and BSA < 1.7 m2 are risk factors associated with grade 2-4 FO during hospitalization for allogeneic HCT with PTCY.

Prediction of CD34+ hematopoietic stem cells in healthy allogeneic stem cell donors on the Optia cell separator based on CE2: Which formula is more correlated with actual CD34+?

BACKGROUND: Peripheral blood-derived hematopoietic stem cells (HSCs) are widely used for various adult stem cell transplants. To obtain sufficient HSCs from healthy volunteer donors during the apheresis process and ensure that the donors are exposed to fewer apheresis-related side effects, calculation methods have been developed for the prediction of processed blood volume or CD34+ count. However, there is no consensus on a formula to predict the volume of blood to be processed or the number of stem cells to be obtained. OBJECTIVE: This study aimed to estimate the predicted blood volume and CD34+ cell counts using collection efficiency (CE)-based formulas and evaluate their accuracy compared to the actual CD34+ cell counts. It also seeks to identify the factors that affect CE. METHODS: Data from 397 healthy, unrelated stem cell donors were retrospectively analyzed. An algorithm using four different CE2 metrics (1st quartile, mean, 3rd quartile, and median) was developed to predict the volume of blood to be processed using the Spectra Optia continuous mononuclear cell collection procedure. RESULTS: When employing the mean CE2 algorithm, the results revealed a strong correlation (r = .894, p < .001) between predicted and actual CD34+ values. The study also identified strong associations between pre-apheresis CD34+, pre-apheresis leukocyte count, the use of two doses of G-CSF, and low CE2. CONCLUSION: These findings suggest that the mean CE2 algorithm could be a potent, straightforward, and accurate tool for predicting CD34+ stem cell counts in healthy allogeneic stem cell donors and potentially optimizing stem cell collection procedures.

Allogeneic hematopoietic cell transplantation from alternative donors in acute myeloid leukemia.

Allogeneic hematopoietic cell transplantation (HCT) potentially provides a cure for patients with acute myeloid leukemia (AML) who are unlikely to be cured with chemotherapy alone. Previously, human leukocyte antigen (HLA)-matched related donors were used exclusively, which made the procedure available for a limited proportion of patients. The introduction of high-resolution HLA-typing technology, innovations in immunosuppressive therapy, and improved supportive care measures have significantly changed the situation. Now, patients without a matched related donor have an ample opportunity to receive allogeneic HCT with the use of matched or mismatched unrelated donors, umbilical cord blood grafts, or haploidentical related donors. The outcomes of alternative donor transplantations have improved over the past decades, and the growth of unrelated donor registries as well as the donor diversification have enhanced the chance of finding a suitable donor. With multiple alternative donor choices available for most patients, the donor selection is becoming increasingly important. To discuss the optimal donor choice in case of unavailability of an HLA-matched related donor, this article reviews the existing literature of retrospective and prospective comparisons of different alternative donor transplantations in AML and discusses the current state-of-art modalities in allogeneic HCT using alternative donors.

Development and validation of reverse-transcription cross-priming amplification-based lateral flow assay for the detection of infectious hematopoietic necrosis virus.

Infectious hematopoietic necrosis virus (IHNV) severely and lethally infects salmonid fish, including Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss) worldwide. Rapid and accurate viral detection is crucial for preventing pathogen spread and minimizing damage. Although several IHNV detection assays have been developed, their analytical and diagnostic performances have not been evaluated and field usability assessments have not been completely validated. Here, we developed a reverse-transcription cross-priming amplification-based lateral flow assay (RT-CPA-LFA) and validated its diagnostic performance. To detect the IHNV, primers were designed based on the consensus sequence of the nucleocapsid (N) gene. Notably, when combined with a lateral flow dipstick, it could visualize the IHNV amplification products within 5min and the detection limit of the developed RT-CPA-LFA was 3.28×105 copies/µL. The diagnostic sensitivity and specificity in fish samples (n=140) were 98.88% and 96.08%, respectively. Moreover, the IHNV detection rate by RT-CPA-LFA in dead rainbow trout artificially injected with the virus was 100%, consistent with to the results obtained from second conventional and real-time PCR, indicating its applicability for rapid IHNV detection and presumptive IHN diagnosis during the endemic period.

Cxcl10 and Cxcr3 regulate self-renewal and differentiation of hematopoietic stem cells.

BACKGROUND: The function of hematopoietic stem cells (HSC) is regulated by HSC internal signaling pathways and their microenvironment. Chemokines and chemokine ligands play important roles in the regulation of HSC function. Yet, their functions in HSC are not fully understood. METHODS: We established Cxcr3 and Cxcl10 knockout mouse models (Cxcr3-/- and Cxcl10-/-) to analyze the roles of Cxcr3 or Cxcl10 in regulating HSC function. The cell cycle distribution of LT-HSC was assessed via flow cytometry. Cxcr3-/- and Cxcl10-/- stem/progenitor cells showed reduced self-renewal capacity as measured in serial transplantation assays. To study the effects of Cxcr3 or Cxcl10 deficient bone marrow microenvironment, we transplanted CD45.1 donor cells into Cxcr3-/-or Cxcl10-/- recipient mice (CD45.2) and examined donor-contributed hematopoiesis. RESULTS: Deficiency of Cxcl10 and its receptor Cxcr3 led to decreased BM cellularity in mice, with a significantly increased proportion of LT-HSC. Cxcl10-/- stem/progenitor cells showed reduced self-renewal capacity in the secondary transplantation assay. Notably, Cxcl10-/- donor-derived cells preferentially differentiated into B lymphocytes, with skewed myeloid differentiation ability. Meanwhile, Cxcr3-deficient HSCs demonstrated a reconstitution disadvantage in secondary transplantation, but the lineage bias was not significant. Interestingly, the absence of Cxcl10 or Cxcr3 in bone marrow microenvironment did not affect HSC function. CONCLUSIONS: The Cxcl10 and Cxcr3 regulate the function of HSC, including self-renewal and differentiation, adding to the understanding of the roles of chemokines in the regulation of HSC function.

A Case of Chronic Granulomatous Disease Masquerading As Tubercular Lymphadenitis in an Infant.

Chronic granulomatous disease (CGD) is a rare inborn error of immunity characterized by recurrent fungal and bacterial infections due to defective nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity. This case report describes an 11-month-old female who was initially diagnosed with tubercular lymphadenitis and presented with fever and bilateral neck swelling. Despite receiving anti-tubercular treatment (ATT) and intravenous antibiotics, the patient experienced recurrent infections and abscesses, prompting further investigation. Laboratory tests revealed normal immunoglobulin levels but abnormal nitroblue tetrazolium (NBT) and dihydrorhodamine (DHR) tests, indicating CGD. Genetic analysis (clinical exome by next-generation sequencing) confirmed a novel NCF2 gene mutation associated with autosomal recessive CGD. This patient was treated with prophylactic antibiotics and antifungals and subsequently underwent successful hematopoietic stem cell transplantation (HSCT). This highlights the diagnostic challenges associated with CGD, particularly in tuberculosis-endemic regions such as India, emphasizing the importance of considering primary immunodeficiency disorders in patients with recurrent infections. Early diagnosis and appropriate treatment, including HSCT, can significantly improve patient outcomes. The patient remained infection-free on prophylactic antimicrobials for 1.5 years post-discharge, demonstrating the potential for a favorable prognosis with timely intervention and comprehensive management.

18FDG PET/CT imaging of adenovirus-associated acute interstitial nephritis after allogeneic bone marrow transplantation.

Adenovirus-associated acute interstitial nephritis (AAIN) should always be considered in the differential diagnosis of acute kidney failure following allogeneic bone marrow transplant. Although not intended for the definitive diagnosis of AAIN, 18FDG PET/CT can be a helpful noninvasive diagnostic tool, especially when a biopsy is not feasible.

History of Hemophagocytic Lymphohistiocytosis.

Hemophagocytic lymphohistiocytosis (HLH) is a severe cytokine storm syndrome (CSS), which until the turn of the century, was barely known but is now receiving increased attention. The history of HLH dates back to 1939 when it was first described in adults, to be followed in 1952 by the first description of its primary, familial form in children. Secondary forms of HLH are far more frequent and occur with infections, malignancies, metabolic diseases, iatrogenic immune suppression, and autoinflammatory/autoimmune diseases. Identification of the genetic defects leading to the defective function of natural killer (NK) cells and cytotoxic T cells as well as the corresponding mouse models have revolutionized our understanding of HLH and of immune function. Diagnosis relies on clinical and laboratory criteria; functional and genetic tests can help separate primary from secondary forms. Treatment with immunochemotherapy and hematopoietic stem cell transplantation has considerably improved survival in children with primary HLH, a formerly uniformly fatal disease.

Salvage Therapy and Allogeneic Hematopoietic Cell Transplantation for the Severe Cytokine Storm Syndrome of Hemophagocytic Lymphohistiocytosis.

Hemophagocytic lymphohistiocytosis (HLH) can be considered as a severe cytokine storm syndrome disorder. HLH typically manifests as a life-threatening inflammatory syndrome characterized by fevers, cytopenias, hepatosplenomegaly, and various other accompanying manifestations such as coagulopathy, hepatitis or liver failure, seizures or altered mental status, and even multi-organ failure. Standard up-front treatments do not always bring HLH into remission or maintain adequate response, and salvage or alternative therapies are often needed. For patients with genetic diseases that cause HLH, curative allogeneic hematopoietic cell transplantation is usually offered to prevent future episodes of life-threatening HLH. Here, we will discuss the options and approaches for salvage therapy and hematopoietic cell transplantation for patients with HLH.

Deubiquitinases at the interplay between hematopoietic stem cell aging and myelodysplastic transformation.

Hematopoietic stem cells (HSC) maintain blood production throughout life. Nevertheless, HSC functionality deteriorates upon physiological aging leading to the increased prevalence of haematological diseases and hematopoietic malignancies in the elderly. Deubiquitinating enzymes (DUBs) by reverting protein ubiquitination ensure proper proteostasis, a key process in HSC maintenance and fitness.

Role of Telomere Length in Radiation Response of Hematopoietic Stem & Progenitor Cells in Newborns.

OBJECTIVE: Wide inter-individual variations in ionizing radiation (IR) responses of neonatal hematopoietic system calls for identifying reliable biomarkers to effectively estimate radiation exposure damages in neonates. METHODS: Association between telomere length (TL) at birth and radiation sensitivity of cord blood hematopoietic stem cells (HSC) from 166 healthy newborns were investigated by assessing their clonogenic differentiation. TL was determined as terminal restriction fragment (TRF) by Southern blot method. RESULTS: TL correlated with surviving fractions of total progenitor colony forming cell (CFC) content at 0.75 Gy (p < 0.05), granulo-macrophagic lineage colony forming units (CFU-GM) at 0.75 Gy (p < 0.05) and erythroid burst forming unit (BFU-E) at 0.75 Gy (p < 0.05) & at 3 Gy (p < 0.05) of newborns. CONCLUSION: Our results indicate risks for HSC clonogenic survival in neonates with shorter telomeres after IR exposure. These observations might aid in considering TL at birth as an assessment factor for radiation related hematopoietic challenges in children.