Efficacy and safety of mammalian target of rapamycin inhibitors in systemic mastocytosis: A nationwide French pilot study

Systemic mastocytosis (SM) corresponds to a rare and heterogeneous spectrum of diseases characterized by the accumulation of atypical mast cells (MCs). Advanced mastocytosis (Adv-SM) is associated with poor survival; in contrast, patients with non-advanced SM (non-Adv-SM) usually have a normal life expectancy but may experience poor quality of life. Despite recent therapeutic progress including tyrosine kinase inhibitors, new treatment options are needed for refractory and/or intolerant patients with both severely symptomatic and Adv-SM. In vitro, the mTOR pathway is activated in MCs from patients bearing the KIT D816V mutation. Furthermore, rapamycin induces the apoptosis of KIT D816V MCs selectively. In this nationwide study, we report the outcomes of patients diagnosed with SM and treated with a mammalian target of rapamycin inhibitor (imTOR) within the French National Reference Center for mastocytosis (CEREMAST). All patients registered were relapsing, treatment-refractory, or ineligible for other cytoreductive therapy. Non-Adv-SM patients received imTOR as a monotherapy (rapamycin/everolimus), and Adv-SM patients received imTOR as a monotherapy or in combination with cytarabine. The objective response rate (ORR) in non-Adv-SM was 60% (partial response in 40% and major response in 20%), including reductions in skin involvement, mediator release symptoms, and serum tryptase. In the Adv-SM group, the ORR was 20% (including one major response and one partial response, both in patients with a KIT D816V mutation), which enabled a successful bridge to allogeneic stem cell transplantation in one patient. Our results suggest that imTOR treatment has potential benefits in patients with SM harboring a KIT D816V mutation.

Comprehensive genetic profiling reveals frequent alterations of driver genes on the X chromosome in extranodal NK/T-cell lymphoma

Extranodal NK/T-cell lymphoma (ENKTCL) is an Epstein-Barr virus (EBV)-related neoplasm with male dominance and a poor prognosis. A better understanding of the genetic alterations and their functional roles in ENKTCL could help improve patient stratification and treatments. Here, we performed comprehensive genetic analysis of 177 ENKTCL cases to delineate the landscape of mutations, copy number alterations (CNAs), and structural variations, identifying 34 driver genes including six previously unappreciated ones, namely HLA-B, HLA-C, ROBO1, CD58, POT1, and MAP2K1. Among them, CD274 (24%) was the most frequently altered, followed by TP53 (20%), CDKN2A (19%), ARID1A (15%), HLA-A (15%), BCOR (14%), and MSN (14%). Chromosome X (chrX) losses were the most common arm-level CNAs in females (~40%), and alterations of four X-linked driver genes (MSN, BCOR, DDX3X, and KDM6A) were more frequent in males and females harboring chrX losses. Among X-linked drivers, MSN was the most recurrently altered, and its expression was lost in approximately one-third of cases using immunohistochemical analysis. Functional studies of human cell lines demonstrated that MSN disruption promoted cell proliferation and NF-κB activation. Moreover, MSN inactivation increased sensitivity to NF-κB inhibition in vitro and in vivo. In addition, recurrent deletions were observed at the origin of replication in the EBV genome (6%). Finally, by integrating the 34 drivers and 19 significant arm-level CNAs, non-negative matrix factorization and consensus clustering identified two molecular groups with different genetic features and prognosis irrespective of clinical prognostic factors. Together, these findings could help improve diagnostic and therapeutic strategies in ENKTCL.

Allogeneic haematopoietic cell transplantation for advanced systemic mastocytosis: Best practice recommendations on behalf of the EBMT Practice Harmonisation and Guidelines Committee

Systemic Mastocytosis (SM) is a multifaceted clinically heterogeneous disease. Advanced SM (AdvSM) comprises three entities: aggressive SM (ASM), mast cell leukaemia (MCL) and SM with an associated hematologic neoplasm (SM-AHN), the latter accounting for 60-70% of all AdvSM cases. Detection of a disease-triggering mutation in the KIT gene (esp. KIT D816V) in >90% of the patients with ASM or SM-AHN has led to a significant improvement in therapeutic options by the implementation of two KIT-targeting kinase inhibitors: midostaurin and avapritinib. Although complete remissions have been reported, neither of these targeted agents is 'curative' in all patients and the duration of responses varies. The median overall survival, depending on the WHO subtype and scoring result, is approximately 1 to 4 years. Although the European Competence Network on Mastocytosis (ECNM) and American Initiative in Mast Cell Diseases (AIM) consensus groups recommend allogeneic haematopoietic cell transplantation (allo-HCT) in drug-resistant and other high-risk patients, there is a relative lack of information to guide clinicians on which patients with AdvSM should be considered for transplant, and how KIT inhibitors may fit into the transplant algorithm, including their use pre- and post-transplant to optimise outcomes. Following the generation of an expert panel with a specialist interest in allo-HCT and mastocytosis, these best practice recommendations were generated according to the European Society for Blood and Marrow Transplantation (EBMT) Practice Harmonisation and guidelines and ECNM methodology. We aim to provide a practical, clinically relevant and up-to-date framework to guide allo-HCT in AdvsM in 2024 and beyond.

Histological characterization of liver involvement in systemic mastocytosis

BACKGROUND AND AIMS

Systemic mastocytosis (SM) is characterized by the accumulation of atypical mast cells (MCs) in organs. Liver histology of SM has been marginally described and accurate histological classification is critical, given the consequences of aggressive SM diagnosis. We aimed to describe the histological features associated with liver SM using updated tools.

METHODS

Using the database of the French Reference Centre for Mastocytosis, we retrospectively identified patients with a liver biopsy (LB) and a diagnosis of SM. All LB procedures were performed according to the local physician in charge and centrally reviewed by an expert pathologist.

RESULTS

A total of 28 patients were included: 6 had indolent SM, 9 had aggressive SM, and 13 had SM with an associated hematologic neoplasm. Twenty-five (89%) patients presented hepatomegaly, and 19 (68%) had portal hypertension. The LB frequently showed slight sinusoid dilatation (82%). Fibrosis was observed in 3/6 indolent SM and in almost all advanced SM cases (21/22), but none of them showed cirrhosis. A high MC burden (>50 MCs/high-power field) was correlated with elevated blood alkaline phosphatase levels (p = .030). The presence of portal hypertension was associated with a higher mean fibrosis grade (1.6 vs. 0.8 in its absence; p = .026). In advanced SM, the presence of nodular regenerative hyperplasia (NRH) was associated with decreased overall survival (9.5 vs. 46.3 months, p = .002).

CONCLUSIONS

MC infiltration induced polymorphic hepatic lesions and the degree of fibrosis is associated with portal hypertension. NRH identifies a poor prognosis subgroup of patients with advanced SM. Assessing liver histology can aid in SM prognostic evaluation.

Time-of-flight scatter rejection in x-ray radiography

Objective.Time-of-flight (TOF) scatter rejection allows for identifying and discarding scattered photons without the use of an anti-scatter grid (ASG). Although TOF scatter rejection was initially presented for cone-beam computed tomography, we propose, herein, to extend this approach to x-ray radiography. This work aims to evaluate with simulations if TOF scatter rejection can outperform ASGs for radiography.Approach.GATE was used to simulate the radiography of a head and a torso and a water cylinder with bone inserts in a system with total timing jitters from 0 ps up to 500 ps full-width-at-half-maximum. The transmission factor of TOF scatter rejection for primary and scattered photons was evaluated as if it were a virtual ASG.Main results.With a total timing jitter of 50 ps, TOF scatter rejection can reach a selectivity of 4.93 with a primary photons transmission of 99%. Reducing the timing jitter close to 0 ps increases the selectivity up to 15.85 for a head and torso radiography, outperforming typical ASGs which usually have a selectivity from 2.5 to 10 with a primary photons transmission from 50% to 70%.Significance.This suggests that TOF scatter rejection may be suitable to replace ASGs in applications requiring lower radiation exposure if sufficiently low timing jitter is achieved.

Pathophysiologic implications of elevated prevalence of hereditary alpha-tryptasemia in all mastocytosis subtypes

BACKGROUND

Mastocytosis and monoclonal mast cell (MC) activation syndrome (MMAS) are heterogeneous conditions characterized by the accumulation of atypical MCs. Despite the recurrent involvement of KIT mutations, the pathophysiologic origin of mastocytosis and MMAS is unclear. Although hereditary α-tryptasemia (HαT, related to TPSAB1 gene duplication) is abnormally frequent in these diseases, it is not known whether the association is coincidental or causal.

OBJECTIVE

We evaluated the prevalence of HαT in all mastocytosis subtypes and MMAS and assessed the pathophysiologic association with HαT.

METHODS

Clinical data, laboratory data, KIT mutations, TPSAB1 duplication (assessed by droplet digital PCR), and HαT prevalence were retrospectively recorded for all patients with mastocytosis and MMAS registered in the French national referral center database and compared to a control cohort. To increase the power of our analysis for advanced systemic mastocytosis (advSM), we pooled our cohort with literature cases.

RESULTS

We included 583 patients (27 with MMAS and 556 with mastocytosis). The prevalence of HαT in mastocytosis was 12.6%, significantly higher than in the general population (5.7%, P = .002) and lower than in MMAS (33.3%, P = .02). HαT+ patients were more likely to have anaphylactic reactions and less likely to have cutaneous lesions than HαT- patients (43.0% vs 24.4%, P = .006; 57.7% vs 75.6%, respectively, P = .006). In the pooled analysis, the prevalence of HαT was higher in advSM (11.5%) than in control cohorts (5.2%, P = .01).

CONCLUSION

Here we confirm the increase incidence of anaphylaxis in HαT+ mastocytosis patients. The increased prevalence of HαT in all subtypes of systemic mastocytosis (including advSM) is suggestive of pathophysiologic involvement.

Correction: Bowers et al. Tart Cherry Extract and Omega Fatty Acids Reduce Behavioral Deficits and Gliosis in the 5xFAD Mouse Model of Alzheimer's Disease. Brain Sci. 2021, 11, 1423

There is an error in the title of the published paper [...].

Advances in stem cell and other therapies for Huntington's disease: An update

Huntington's disease (HD) is a neurodegenerative disorder caused by an autosomal dominant mutation leading to an abnormal CAG repeat expansion. The result is the synthesis of a toxic misfolded protein, called the mutant huntingtin protein (mHTT). Most current treatments are palliative, but the latest research has expanded into multiple modalities, including stem cells, gene therapy, and even the use of 3D cell structures, called organoids. Stem cell research as a treatment for HD has included the use of various types of stem cells, such as mesenchymal stem cells, neural stem cells, embryonic stem cells, and even reprogrammed stem cells called induced pluripotent stem cells. The goal has been to develop stem cell transplant grafts that will replace the existing mutated neurons, as well as release existing trophic factors for neuronal support. Additionally, research in gene modification using CRISPR-Cas9, PRIME editing, and other forms of genetic modifications are continuing to evolve. Most recently, advancements in stem cell modeling have yielded 3D stem cell tissue models, called organoids. These organoids offer the unique opportunity to transplant a structured stem cell graft which, ideally, models normal human brain tissue more accurately. This manuscript summarizes the recent research in stem cells, genetic modifications, and organoids as a potential for treatment of HD.

Inducible Knockout of 14-3-3β Attenuates Proliferation and Spheroid Formation in a Human Glioblastoma Cell Line U87MG

Glioblastomas (GBs) are the most common and malignant brain tumors in adults. A protein encoded by the gene YWHAB, 14-3-3β, is commonly found to be upregulated throughout the initiation and progression of GB. The 14-3-3β has oncogenic roles in several different types of cancer cells through interactions with proteins such as Bad, FBI1, Raf-1, Cdc25b, and others. Previous RNA interference studies have shown that 14-3-3β promotes proliferation, cell cycle progression, and migration and invasion of GB cells. However, despite the many oncogenic functions of 14-3-3β, a CRISPR/Cas9 knockout model of 14-3-3β has not been investigated. This study confirmed previous findings and showed that siRNA inhibition of 14-3-3β results in reduced cellular proliferation in a human glioblastoma cell line, U87MG. We also used a YWHAB Tet-On CRISPR/Cas9 U87MG cell line that, upon doxycycline induction, leads to robust Cas9 expression and subsequent knockout of 14-3-3β. Using this model, we show that loss of 14-3-3β significantly reduces cellular proliferation and spheroid formation of U87MG cells.

French guidelines for the etiological workup of eosinophilia and the management of hypereosinophilic syndromes

Eosinophilic-related clinical manifestations are protean and the underlying conditions underpinning eosinophilia are highly diverse. The etiological workup of unexplained eosinophilia/hypereosinophilia can be challenging, and can lead sometimes to extensive, inappropriate, costly and/or invasive investigations. To date, guidelines for the etiological workup and management of eosinophilia are mainly issued by hematologists, and thus mostly cover the scope of clonal hypereosinophilic syndromes (HES). Here, thanks to an extensive literature review, and thanks to the joint work of a large panel of experts involving physicians from both adult and pediatric medicine and from various subspecialties (as well as a representative of a patients' association representative), we provide recommendations for both the step-by step diagnostic workup of eosinophilia (whether unexplained or within specific contexts) as well as the management and follow-up of the full spectrum of eosinophilic disorders (including clonal, reactive, lymphocytic and idiopathic HES, as well as single-organ diseases). Didactic prescription summaries intended to facilitate the prescription of eosinophil-targeted drugs are also provided, as are practical diagnostic and therapeutic algorithms. Lastly, this set of recommendations also includes a summary intended for general practitioners, as well as an overview of the therapeutic patient education program set up by the French reference center for HES. Further updates will be mandatory as new validated information emerges.

Efficacy of a short sandwich protocol, methotrexate, gemcitabine, L-asparaginase and dexamethasone chemotherapy combined with radiotherapy, in localised newly diagnosed NK/T-cell lymphoma: A French retrospective study

Extranodal NK/T-cell lymphoma, nasal type is a rare and aggressive form of lymphoma, historically associated with poor prognosis. We report here the results of a retrospective multi-centre study evaluating the efficacy of MGAD (methotrexate, gemcitabine, L-asparaginase and dexamethasone) regimen (two cycles) combined with 'sandwich' radiotherapy in 35 patients with localised newly diagnosed extranodal NK/T-cell lymphoma. Thirty-two patients (91%) reached complete remission. With a long median follow-up of 59.6 months, progression-free and overall survival at 2 and 5 years were 71%, 80% and 53%, 73%, respectively. Around one third of the patients experienced relapse within a median time of 14.5 months. Side-effects were manageable with grades 3-4 cytopenias, mucositis and infection in 50%, 24% and 21% of the cases, respectively. Monitoring of asparaginase activity was performed in 13 patients and showed inactivation of the drug in seven (54%) patients. Our results indicate that a short therapy by sandwich MGAD chemoradiotherapy is a tolerable and effective treatment option in localised newly diagnosed extranodal NK/T-cell lymphoma patients.

Therapeutic management and outcome of patients with advanced systemic mastocytosis treated with midostaurin: A comprehensive real-life study in the French national healthcare database

Advanced Systemic Mastocytosis (Adv-SM) is rare and has a poor prognosis. Midostaurin (Rydapt^® ) is one of the few treatments for Adv-SM in Europe. The study aims were to describe the characteristics of patients treated with midostaurin, their treatment modalities, outcomes, and serious events requiring hospitalization. This retrospective observational study was conducted using the French National Healthcare Database (SNDS) and included adult Adv-SM patients treated with midostaurin between 01-01-2012 and 09-30-2018. Kaplan-Meier method was used to assess survival and treatment duration. Eighty-one patients were included: 37 with Aggressive Systemic Mastocytosis (SM) (46%), 31 with SM with an Associated Hematological Neoplasm (38%), and 4 with Mast Cell Leukemia (5%). The SM subtype was undetermined in 9 patients (11%). The median age was 67 years; 64% of patients were male. Over the mean follow-up of 11.4 months, median midostaurin treatment duration was 8.4 months and 28 patients (35%) were still under treatment at the end of the study. One-year and 5-year overall survival rates estimated since the time of diagnosis were 83% and 56%, respectively. Twelve serious events (among those frequently reported during clinical trials and compassionate use) requiring hospitalization were identified; a causal association with Adv-SM treatment could neither be excluded nor established. In this first real-life study on patients treated with midostaurin for Adv-SM, the patients' characteristics, their management, treatment discontinuation, and survival were in line with previous results (compassionate use and clinical trials).

BLNK mutation associated with T-cell LGL leukemia and autoimmune diseases: Case report in hematology

We present the case of a female patient with a heterozygous somatic BLNK mutation, a T-cell LGL (large granular lymphocyte) leukemia, and multiple autoimmune diseases. Although this mutation seems uncommon especially in this kind of clinical observation, it could represent a new mechanism for autoimmune diseases associated with LGL leukemia. The patient developed several autoimmune diseases: pure red blood cell apalsia, thyroiditis, oophoritis, and alopecia areata. She also presented a T-cell LGL leukemia which required treatment with corticosteroids and cyclophosphamide, with good efficacy. Interestingly, she had no notable infectious history. The erythroblastopenia also resolved, the alopecia evolves by flare-ups, and the patient is still under hormonal supplementation for thyroiditis and oophoritis. We wanted to try to understand the unusual clinical picture presented by this patient. We therefore performed whole-genome sequencing, identifying a heterozygous somatic BLNK mutation. Her total gamma globulin level was slightly decreased. Regarding the lymphocyte subpopulations, she presented a B-cell deficiency with increased autoreactive B-cells and a CD4+ and Treg deficiency. This B-cell deficiency persisted after complete remission of erythroblastopenia and LGL leukemia. We propose that the persistent B-cell deficiency linked to the BLNK mutation can explain her clinical phenotype.

Reduced peripheral blood dendritic cell and monocyte subsets in MDS patients with systemic inflammatory or dysimmune diseases

BACKGROUND

Systemic inflammatory and autoimmune diseases (SIADs) occur in 10-20% of patients with myelodysplastic syndrome (MDS). Recently identified VEXAS (Vacuoles, E1 enzyme, X-linked, Autoinflammatory, Somatic) syndrome, associated with somatic mutations in UBA1 (Ubiquitin-like modifier-activating enzyme 1), encompasses a range of severe inflammatory conditions along with hematological abnormalities, including MDS. The pathophysiological mechanisms underlying the association between MDS and SIADs remain largely unknown, especially the roles of different myeloid immune cell subsets. The aim of this study was to quantitatively evaluate peripheral blood myeloid immune cells (dendritic cells (DC) and monocytes) by flow cytometry in MDS patients with associated SIAD (n = 14, most often including relapsing polychondritis or neutrophilic dermatoses) and to compare their distribution in MDS patients without SIAD (n = 23) and healthy controls (n = 7). Most MDS and MDS/SIAD patients had low-risk MDS. Eight of 14 (57%) MDS/SIAD patients carried UBA1 somatic mutations, defining VEXAS syndrome.Compared with MDS patients, most DC and monocyte subsets were significantly decreased in MDS/SIAD patients, especially in MDS patients with VEXAS syndrome. Our study provides the first overview of the peripheral blood immune myeloid cell distribution in MDS patients with associated SIADs and raises several hypotheses: possible redistribution to inflammation sites, increased apoptosis, or impaired development in the bone marrow.

Targeting Serotonin With Common Antidepressants Induces Rapid Recovery From Cytopenia

The hematopoietic system uses several, yet undiscovered, factors to adapt to stresses such as chemotherapy, infections, or bleeding. Serotonin is commonly known as a neurotransmitter but is also produced and used in peripheral organs. In particular, we have shown that serotonin synthesized in the bone marrow is necessary for erythroid progenitors' survival and proliferation. Serotonin levels can be increased by FDA approved antidepressants called selective serotonin reuptake inhibitors (SSRI). In this work, we report a previously unknown role of SSRI in the recovery of cytopenia, after autologous hematopoietic stem cell transplantation in patients and after sub-lethal irradiation in mice. We also observed an unexpected cooperation between SSRI and G-CSF on the improvement of the 3 hematopoietic lineages. Of note, SSRI do not seem to affect blood cells production in the absence of stress-induced hematopoiesis. We propose that the serotonergic system could be a valuable therapeutic target in stress-induced cytopenia, especially as a rescue after radiation or chemotherapy.

Effective Anti-SARS-CoV-2 Immune Response in Patients With Clonal Mast Cell Disorders

BACKGROUND

Mast cells are key players in innate immunity and the T_H2 adaptive immune response. The latter counterbalances the T_H1 response, which is critical for antiviral immunity. Clonal mast cell activation disorders (cMCADs, such as mastocytosis and clonal mast cell activation syndrome) are characterized by abnormal mast cell accumulation and/or activation. No data on the antiviral immune response in patients with MCADs have been published.

OBJECTIVE

To study a comprehensive range of outcomes in patients with cMCAD with PCR- or serologically confirmed coronavirus disease 2019 and to characterize the specific anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immune response in this setting.

METHODS

Clinical follow-up and outcome data were collected prospectively over a 12-month period by members of the French Centre de Référence des Mastocytoses rare disease network. Anti-SARS-CoV-2-specific T-cell activity was measured with an ELISA, and humoral responses were evaluated by assaying circulating levels of specific IgG, IgA, and neutralizing antibodies.

RESULTS

Overall, 32 patients with cMCAD were evaluated. None required noninvasive or mechanical ventilation. Two patients were admitted to hospital for oxygen and steroid therapy. The SARS-CoV-2-specific immune response was characterized in 21 of the 32 patients. Most had high counts of circulating SARS-CoV-2-specific, IFN-γ-producing T cells and high titers of neutralizing antispike IgGs. The patients frequently showed spontaneous T-cell IFN-γ production in the absence of stimulation; this production was correlated with basal circulating tryptase levels (a marker of the mast cell burden).

CONCLUSIONS

Patients with cMCADs might not be at risk of severe coronavirus disease 2019, perhaps due to their spontaneous production of IFN-γ.

Neuropilin-1 cooperates with PD-1 in CD8+ T-cells predicting outcomes in melanoma patients treated with anti-PD1

Targeting immune checkpoints, such as Programmed cell Death 1 (PD1), has improved survival in cancer patients by restoring antitumor immune responses. Most patients, however, relapse or are refractory to immune checkpoint blocking therapies. Neuropilin-1 (NRP1) is a transmembrane glycoprotein required for nervous system and angiogenesis embryonic development, also expressed in immune cells. We hypothesized that NRP1 could be an immune checkpoint co-receptor modulating CD8⁺ T cells activity in the context of the antitumor immune response. Here, we show that NRP1 is recruited in the cytolytic synapse of PD1⁺CD8⁺ T cells, cooperates and enhances PD-1 activity. In mice, CD8⁺ T cells specific deletion of Nrp1 improves anti-PD1 antibody antitumor immune responses. Likewise, in human metastatic melanoma, the expression of NRP1 in tumor infiltrating CD8⁺ T cells predicts poor outcome of patients treated with anti-PD1. NRP1 is a promising target to overcome resistance to anti-PD1 therapies.

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NRP1 modulates PD1 activity secondary to complexes formation on CD8⁺ T cells

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Anti-PD1 therapy is synergistic with NRP1 specific deletion on CD8⁺ T cells in mouse

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NRP1 expression on CD8⁺ TILs predicts poor outcome in patients treated with anti-PD1

Cell-free DNA sequencing as a potential screening tool for phase I targeted treatment in refractory/relapse diffuse large B cell lymphoma

Not available.

Abstract TP254: Reduction Of Behavior Deficits Following Delivery Of Sox2 To Stroke Rats Using Mixed-Surface PAMAM Dendrimer Nanomolecules

A major drawback of current stroke treatment strategies (such as the use of tPA) includes time sensitivity to achieve maximum therapeutic efficacy. Alternative treatments include less time-sensitive approaches and utilize in vivo reprogramming of resident reactive astrocytes to repopulate the lost neurons in sufficient numbers. In this study, we tested whether a transcription factor, hSOX2, when expressed under a glial cell-specific GFAP promoter, could sufficiently reprogram astrocytes in and around the infarct to enhance their differentiation into neurons. To achieve delivery of the hSOX2 gene, we utilize PAMAM dendrimers, which are nanomolecules with a well-established capacity of delivering drugs/ large biomolecules to the brain across the BBB and confer intrinsic anti-inflammatory properties. Dendrimers are comprised of an interior dendritic structure with modifiable sizes, and an exterior surface with functional surface groups. The G4 PAMAM dendrimers used in this study has 10% of the surface covered with amine groups and 90% of the surface covered with hydroxyl groups (G4-90/10). These dendrimers are less toxic and readily form complexes with plasmids up to 14 kb in size (dendriplex) and successfully deliver cargo in vitro and in vivo . Four days following stroke inductions in Sprague Dawley rats via MCAo, the hSOX2 dendriplex was injected into the ipsilateral corpus callosum. A battery of behavior tests, such as cylinder and ladder tasks, were used to assess motor abilities of the treated and untreated stroked and sham-operated control rats. Moreover, the animals underwent In vivo Imaging System to confirm the presence of dendriplex in the brain. Five weeks following the injections, the brains were collected and processed, using immunohistochemistry, to detect the complex and measure the amount of hSOX2 gene expression. The size of the brain infarct was measured using the conventional H&E staining. Our results indicated that the dendrimers were able to deliver the hSOX2 gene to the stroke brain and this significantly reduced motor deficits, relative to untreated stroked rats. These results indicated that PAMAM dendrimers effectively deliver genes into the brain and that the hSOX2 gene can successfully reduce motor deficits following stroke.

Refined diagnostic criteria for bone marrow mastocytosis: a proposal of the European competence network on mastocytosis

In the current classification of the World Health Organization (WHO), bone marrow mastocytosis (BMM) is a provisional variant of indolent systemic mastocytosis (ISM) defined by bone marrow involvement and absence of skin lesions. However, no additional diagnostic criteria for BMM have been proposed. Within the registry dataset of the European Competence Network on Mastocytosis, we compared characteristics and outcomes of 390 patients with BMM and 1175 patients with typical ISM. BMM patients were significantly older, predominantly male, had lower tryptase and lower burden of neoplastic mast cells, and displayed a higher frequency of allergic reactions, mainly triggered by Hymenoptera, than patients with typical ISM. The estimated 10-year progression-free survival of BMM and typical ISM was 95.9% and 92.6%, respectively. In BMM patients defined by WHO-based criteria, the presence of one B-Finding and tryptase level ≥125 ng/mL were identified as risk factors for progression in multivariate analyses. BMM patients without any of these risk factors were found to have better progression-free survival (p < 0.05) and better overall survival (p < 0.05) than other ISM patients. These data support the proposal to define BMM as a separate SM variant characterized by SM criteria, absence of skin lesions, absence of B-Findings, and tryptase levels <125 ng/mL.

The association of Greig syndrome and mastocytosis reveals the involvement of the hedgehog pathway in advanced mastocytosis

Mastocytosis is a heterogeneous disease characterized by an abnormal accumulation of mast cells (MCs) in 1 or several organs. Although a somatic KIT D816V mutation is detected in ∼85% of patients, attempts to demonstrate its oncogenic effect alone have repeatedly failed, suggesting that additional pathways are involved in MC transformation. From 3 children presenting with both Greig cephalopolysyndactyly syndrome (GCPS, Mendelian Inheritance in Man [175700]) and congenital mastocytosis, we demonstrated the involvement of the hedgehog (Hh) pathway in mastocytosis. GCPS is an extremely rare syndrome resulting from haploinsufficiency of GLI3, the major repressor of Hh family members. From these familial cases of mastocytosis, we demonstrate that the Hh pathway is barely active in normal primary MCs and is overactive in neoplastic MCs. GLI3 and KIT mutations had a synergistic, tumorigenic effect on the onset of mastocytosis in a GCPS mouse model. Finally, Hh inhibitors suppressed neoplastic MC proliferation in vitro and extend the survival time of mice with aggressive systemic mastocytosis (ASM). This work revealed, for the first time, the involvement of Hh signaling in the pathophysiology of mastocytosis and demonstrated the cooperative effects of the KIT and Hh oncogenic pathways in mice with ASM, leading to the identification of new promising therapeutic targets.

USAID Associated with Myeloid Neoplasm and VEXAS Syndrome: Two Differential Diagnoses of Suspected Adult Onset Still's Disease in Elderly Patients

Background: Patients with solid cancers and hematopoietic malignancy can experience systemic symptoms compatible with adult-onset Still’s disease (AOSD). The newly described VEXAS, associated with somatic UBA1 mutations, exhibits an overlap of clinical and/or biological pictures with auto inflammatory signs and myelodysplastic syndrome (MDS). Objectives: To describe a cohort of patients with signs of undifferentiated systemic autoinflammatory disorder (USAID) concordant with AOSD and MDS/chronic myelomonocytic leukemia (CMML) and the prevalence of VEXAS proposed management and outcome. Methods: A French multicenter retrospective study from the MINHEMON study group also used for other published works with the support of multidisciplinary and complementary networks of physicians and a control group of 104 MDS/CMML. Results: Twenty-six patients were included with a median age at first signs of USAID of 70.5 years with male predominance (4:1). Five patients met the criteria for confirmed AOSD. The most frequent subtypes were MDS with a blast excess (31%) and MDS with multilineage dysplasia (18%). Seven patients presented with acute myeloid leukemia and twelve died during a median follow-up of 2.5 years. Six out of 18 tested patients displayed a somatic UBA1 mutation concordant with VEXAS, including one woman. High-dose corticosteroids led to a response in 13/16 cases and targeted biological therapy alone or in association in 10/12 patients (anakinra, tocilizumab, and infliximab). Azacytidine resulted in complete or partial response in systemic symptoms for 10/12 (83%) patients including 3 VEXAS. Conclusions: Systemic form of VEXAS syndrome can mimic AOSD. The suspicion of USAID or AOSD in older males with atypia should prompt an evaluation of underlying MDS and assessment of somatic UBA1 mutation.

Tart Cherry Extract and Omega Fatty Acids Reduce Behavioral Deficits, Gliosis, and Amyloid-Beta Deposition in the 5xFAD Mouse Model of Alzheimer's Disease

Combined treatments using polyphenols and omega fatty acids provide several therapeutic benefits for a variety of age-related disorders, including Alzheimer's disease (AD). Previously, we found a commercial product, Total Body Rhythm (TBR), consisting of tart cherry extract, a potent polyphenol, and omega fatty acids, significantly reduced memory, and neuropathological deficits in the 192 IgG-saporin mouse model of AD. The present study assessed the efficacy of TBR for treating behavioral and neuropathological deficits in the 5xFAD model of AD. Both 6- and 12-month-old 5xFAD mice and age-matched wild-type controls received TBR (60 mg/kg) or the equivalent dose of vehicle (0.5% methylcellulose) via oral administration, every other day for two months. All mice were tested in the open field (OF), novel object recognition (NOR), and the Morris water maze (MWM) tasks. In addition, neuronal morphology, neurodegeneration, Aβ plaque load, and glial activation were assessed. TBR treatment reduced memory deficits in the MWM and NOR tests and lessened anxiety levels in the OF task, mostly in the 6-month-old male mice. TBR also protected against neuron loss, reduced activation of astrocytes and microglia, primarily in 6-month-old mice, and attenuated Aβ deposition. These results suggest that the combination of tart cherry extract and omega fatty acids in TBR can reduce AD-like deficits in 5xFAD mice.

Azacitidine for patients with Vacuoles, E1 Enzyme, X-linked, Autoinflammatory, Somatic syndrome (VEXAS) and myelodysplastic syndrome: data from the French VEXAS registry

Azacitidine can be effective in myelodysplastic syndromes (MDS) associated with inflammatory/autoimmune diseases. Vacuoles, E1 Enzyme, X-linked, Autoinflammatory, Somatic syndrome (VEXAS) is a new monogenic autoinflammatory syndrome caused by somatic ubiquitin-like modifier-activating enzyme 1 (UBA1) mutation, often associated with MDS, whose treatment is difficult and not yet codified. Based on a French nationwide registry of 116 patients with VEXAS, we report the efficacy and safety of azacitidine treatment in 11 patients with VEXAS with MDS. Clinical response of VEXAS to azacitidine was achieved in five patients (46%), during 6, 8+, 12, 21, 27+ months respectively, suggesting that azacitidine can be effective in selected patients with VEXAS and associated MDS.

Further characterization of clinical and laboratory features occurring in VEXAS syndrome in a large-scale analysis of multicenter case-series of 116 French patients

BACKGROUND

A new autoinflammatory syndrome related to somatic mutations of UBA1 was recently described and called VEXAS syndrome.

OBJECTIVE

To describe clinical characteristics, laboratory findings and outcomes of VEXAS syndrome.

DESIGN

Case-series.

SETTING

Patients referred to a French multicenter registry between November 2020 and May 2021.

PATIENTS

116 patients with VEXAS syndrome.

MEASUREMENTS

Frequency and median of parameters and vital status, from diagnosis to the end of the follow-up.

RESULTS

Main clinical features were skin lesions (83.5%), non-infectious fever (63.6%), weight loss (62%), lung involvement (49.6%), ocular symptoms (38.8%), relapsing chondritis (36.4%), venous thrombosis (34.7%), lymph nodes (33.9%), and arthralgia (27.3%). Hematological disease was present in 58 cases (50%), considered as myelodysplastic syndrome (MDS, n= 58) and monoclonal gammapathy of unknown significance (n=12).UBA1 mutations included p.M41T (44.8%), p.M41V (30.2%), p.M41L (18.1%), and splice mutations (6.9%). After a median follow-up of 3.0 years, 18 patients died (15.5%), from infectious origin (n=9) and MDS progression (n=3). Unsupervised analysis identified 3 clusters: cluster 1 (47%) with mild-to-moderate disease; cluster 2 (16%) with underlying MDS and higher mortality rates; cluster 3 (37%) with constitutional manifestations, higher C-reactive protein levels and less frequent chondritis. Five-year probability of survival was 84.2% in cluster 1, 50.5 % in cluster 2, and 89.6% in cluster 3. UBA1 p.Met41Leu mutation was associated with a better prognosis.

CONCLUSION

VEXAS syndrome displays a large spectrum of organ manifestations and shows different clinical and prognostic profiles. It also raises a potential impact of the identified UBA1 mutation.

Housing R6/2 Mice with Wild-Type Littermates Increases Lifespan

The R6/2 murine model of Huntington's disease (HD) is extensively used in HD research. The current study replicates and extends previous work assessing the impact of housing R6/2 mice with healthy wild-type (WT) littermates on disease progression. The current study extends the previous finding by including male cohorts and the use of a standard diet and water regimen, as opposed to the enhanced diet used in the previous study. This study found that the inclusion of healthy wild-type (WT) littermates, alone, improved survivabilty in R6/2 mice, but did not have a significant impact on weight loss.

Clinical significance of the loss of CD20 antigen on tumor cells in patients with relapsed or refractory follicular lymphoma

Aim: Anti-CD20 monoclonal antibody is a cornerstone therapy for follicular lymphoma. Following anti-CD20 therapy, a potential decrease in CD20 antigen, and therefore a loss of the tumor target might be expected. However, the incidence and clinical significance of CD20 loss on tumor cells in patients with relapsed or refractory follicular lymphoma are unknown. This study aims to investigate the incidence and outcome of patients with relapsed or refractory follicular lymphoma patients harboring the loss of the tumor target, CD20. Methods: All consecutive adult patients with relapsed or refractory follicular lymphoma referred to the Early Drug Department at Gustave Roussy were included. The main objectives were to assess the incidence and prognosis of the loss in expression of CD20 antigen on the surface of tumor cells on patient outcome. Results: Over the study period 2013-2018, 131 patients were screened for clinical trials with B-cell malignancies in the early drug department of Gustave Roussy in France. Forty-four patients presented with relapsed or refractory follicular lymphoma and 32 had tumor biopsies at the time of relapse that were retained for analysis. The median (range) age was 67.5 years (55.3-75.3) and the median number of prior anti-cancer systemic therapies was 3 (2-4). At the time of relapse, CD20 expression was positive in 84% of tumors (n = 27) and negative in 16% of tumors (n = 5). At a median follow-up of 18.3 (0.6-83.3) months, CD20 negativity was associated with a poorer prognosis with a median overall survival of 8.9 months (95%CI: 2.4-19.1) in comparison to CD20 positive patients (28.3 months, 95%CI: 25.1-75.3 months, P = 0.019). Conclusion: The loss of the tumor target antigen, CD20, occurred in 16% of patients with relapse or refractory follicular lymphoma. Due to confounding factors in patients who received anti-CD20 immunotherapy, it was not possible to formally establish the prognostic significance of CD20 negativity. However, we suggest that a check for CD20 antigen positivity nevertheless be performed to adapt subsequent therapies for patients with relapsed or refractory follicular lymphoma.

Attenuated cytarabine, etoposide, dexamethasone plus rituximab (R-Mini-CYVE) regimen for patients with relapsed or refractory B-cell non-Hodgkin's lymphoma not eligible for intensive chemotherapy

OBJECTIVES

To evaluate the efficacy and tolerability of an attenuated immunochemotherapy regimen based on cytarabine, etoposide and dexamethasone plus rituximab (R-mini-CYVE) in patients with relapsed or refractory B-cell non-Hodgkin's lymphoma (NHL).

METHODS

We included pretreated adult patients with B-cell NHL who were ineligible for high-dose immunochemotherapy (HDT). Cytarabine and etoposide were given at four different dose levels, depending on the patient's frailty. Up to 8 cycles were administered.

RESULTS

Between 2013 and 2019, 56 patients with diffuse large B-cell lymphoma (n = 45, 80%) and indolent B-cell lymphoma (n = 11, 20%) were included. Median age was 75 (range: 36-88). Nineteen patients (35%) had a performance status ≥2. Patients received a median of 4 cycles of R-mini-CYVE. The objective response and the complete response rates were 50% and 33%, respectively. Median progression-free survival and overall survival times were 5.7 (95% CI: 0.5-10.9) and 14.7 (95% CI: 3.5-25.9) months, respectively. Grade ≥3 anaemia, thrombocytopenia and neutropenia occurred in 44%, 55% and 60% of the patients, respectively. The most frequent non-haematological grade ≥3 adverse events were sepsis (21%), fatigue (13%) and cytarabine-related neurotoxicity (5%).

CONCLUSION

R-mini-CYVE demonstrated a meaningful antitumour efficacy and an acceptable safety profile in patients with relapsed/refractory B-cell NHL who were ineligible for HDT.

Dissociation of humoral and cellular immune responses in kidney transplant recipients with EBV mucocutaneous ulcer

EBV-positive mucocutaneous ulcer (EBV-MCU) is a rare EBV-positive B-cell lymphoproliferative disorder occurring in immunocompromised patients such as patients with solid organ or hematopoietic stem cells transplantation. EBV-MCU often consists of an isolated and circumscribed cutaneous or mucosal ulcerative lesion with a self-limited growth potential and a high regression rate upon immunosuppressive treatment withdrawal or rituximab therapy. Nevertheless, the pathophysiology of this latent infection leading to clonal lymphoproliferation is not well established. We report here two cases of EBV-MCU in kidney transplant recipients with a dissociated immune response to EBV with the absence of EBV-related antibodies and a positive T-cell response to EBV suggesting a potential specific oncogenic mechanism in this lymphoproliferative disorder.

A New Digital Method for Counting Mast Cells in Cutaneous Specific Lesions of Mastocytosis: A Series of Adult Cases of Mastocytosis With Clinical-Pathological Correlations

ABSTRACT

Cutaneous mastocytosis is characterized by the abnormal accumulation of mast cells in the skin. However, mast cell counting is not always easy and reproducible with classical methods. This work aims to demonstrate the reliability, usability, and virtues of a new software used on digital tablets for counting mast cells in cutaneous specific lesions of mastocytosis, to assess differences in mast cell counts between clinical subtypes of mastocytosis in the skin, and to consider the feasibility of applying a diagnostic mast cell count cutoff to urticaria pigmentosa, which is the most frequent form of cutaneous mastocytosis. Using a new digital tablet software that was accessible by multiple observers through its own wireless network and allowed high resolution of the image without data compression, we counted the number of mast cells on slides of patients and control skins immunostained for CD117. We found that our counting method was highly reproducible and that the new software allowed very quick counting. We evidenced strong differences in the mast cell count between most of the clinical subtypes of mastocytosis in the skin. However, when applied to a subset of patients with urticaria pigmentosa, a diagnostic cutoff in the mast cell count lacked sensitivity. Thus, our digital method for counting CD117-immunostained mast cells was highly accurate and was of a significant value for the diagnosis of mastocytosis in the skin. However, some subtypes with low mast cell counts will still require the application of additional diagnostic criteria.

Cytogenetic and molecular aberrations and worse outcome for male patients in systemic mastocytosis

In systemic mastocytosis (SM), the clinical features and survival vary greatly. Patient-related factors determining the outcome in SM are largely unknown. Methods: We examined the impact of sex on the clinical features, progression-free survival (PFS), and overall survival (OS) in 3403 patients with mastocytosis collected in the registry of the European Competence Network on Mastocytosis (ECNM). The impact of cytogenetic and molecular genetic aberrations on sex differences was analyzed in a subset of patients. Results: Of all patients enrolled, 55.3% were females. However, a male predominance was found in a subset of advanced SM (AdvSM) patients, namely SM with an associated hematologic neoplasm (SM-AHN, 70%; p < 0.001). Correspondingly, organomegaly (male: 23% vs. female: 13%, p = 0.007) was more, whereas skin involvement (male: 71% vs. female: 86%, p = 0.001) was less frequent in males. In all patients together, OS (p < 0.0001) was significantly inferior in males, and also within the WHO sub-categories indolent SM, aggressive SM (ASM) and SM-AHN. PFS was significantly (p = 0.0002) worse in males when all patients were grouped together; due to low numbers of events, this significance persisted only in the subcategory smoldering SM. Finally, prognostically relevant cytogenetic abnormalities (10% vs. 5%, p = 0.006) or molecular aberrations (SRSF2/ASXL1/RUNX1 profile; 63% vs. 40%, p = 0.003) were more frequently present in males. Conclusions: Male sex has a major impact on clinical features, disease progression, and survival in mastocytosis. Male patients have an inferior survival, which seems related to the fact that they more frequently develop a multi-mutated AdvSM associated with a high-risk molecular background.

Mobilized Multipotent Hematopoietic Progenitors Stabilize and Expand Regulatory T Cells to Protect Against Autoimmune Encephalomyelitis

Achieving immunoregulation via in vivo expansion of Foxp3⁺ regulatory CD4⁺ T cells (Treg) remains challenging. We have shown that mobilization confers to multipotent hematopoietic progenitors (MPPs) the capacity to enhance Treg proliferation. Transcriptomic analysis of Tregs co-cultured with MPPs revealed enhanced expression of genes stabilizing the suppressive function of Tregs as well as the activation of IL-1β-driven pathways. Adoptive transfer of only 25,000 MPPs effectively reduced the development of experimental autoimmune encephalomyelitis (EAE), a pre-clinical model for multiple sclerosis (MS). Production of the pathogenic cytokines IL-17 and GM-CSF by spinal cord-derived CD4⁺ T-cells in MPP-protected recipients was reduced while Treg expansion was enhanced. Treg depletion once protection by MPPs was established, triggered disease relapse to the same level as in EAE mice without MPP injection. The key role of IL-1β was further confirmed in vivo by the lack of protection against EAE in recipients of IL-1β-deficient MPPs. Mobilized MPPs may thus be worth considering for cell therapy of MS either per se or for enrichment of HSC grafts in autologous bone marrow transplantation already implemented in patients with severe refractory multiple sclerosis.

Solid Lipid Curcumin Particles Protect Medium Spiny Neuronal Morphology, and Reduce Learning and Memory Deficits in the YAC128 Mouse Model of Huntington's Disease

Huntington's disease (HD) is a genetic neurodegenerative disorder characterized by motor, cognitive, and psychiatric symptoms, accompanied by massive neuronal degeneration in the striatum. In this study, we utilized solid lipid curcumin particles (SLCPs) and solid lipid particles (SLPs) to test their efficacy in reducing deficits in YAC128 HD mice. Eleven-month-old YAC128 male and female mice were treated orally with SLCPs (100 mg/kg) or equivalent volumes of SLPs or vehicle (phosphate-buffered saline) every other day for eight weeks. Learning and memory performance was assessed using an active-avoidance task on week eight. The mice were euthanized, and their brains were processed using Golgi-Cox staining to study the morphology of medium spiny neurons (MSNs) and Western blots to quantify amounts of DARPP-32, brain-derived neurotrophic factor (BDNF), TrkB, synaptophysin, and PSD-95. We found that both SLCPs and SLPs improved learning and memory in HD mice, as measured by the active avoidance task. We also found that SLCP and SLP treatments preserved MSNs arborization and spinal density and modulated synaptic proteins. Our study shows that SLCPs, as well as the lipid particles, can have therapeutic effects in old YAC128 HD mice in terms of recovering from HD brain pathology and cognitive deficits.

Effects of azacitidine in 93 patients with IDH1/2 mutated acute myeloid leukemia/myelodysplastic syndromes: a French retrospective multicenter study

Isocitrate dehydrogenase 1 (IDH1) and 2 (IDH2) mutations in Myeloid Neoplams (MNs) exhibit DNA hypermethylation via 2-hydroxyglutarate (2HG) over-production. Clinical impact of azacitidine (AZA) remains inconsistent in IDH1/2-mutated MNs and the potential of serum 2HG as a suitable marker of response to AZA is unknown. To address these questions, we retrospectively analyzed 93 MNs patients (78 AML, 11 MDS, 4 CMML) with IDH1/2 mutations treated with AZA. After a median of 5 cycles of AZA, overall response rate was 28% (including 15% complete remission) and median OS was 12.3 months (significantly shorter in AML compared to MDS/CMML patients). In multivariate analysis of AML patients, DNMT3A mutation was associated with shorter OS while IDH1/2 mutation subtypes had no independent impact. No difference was observed in serum 2HG levels upon AZA treatment between responding and refractory patients suggesting that serum 2HG cannot be used as a surrogate marker of AZA response.

XPO1 regulates erythroid differentiation and is a new target for the treatment of β-thalassemia

β-thalassemia major (β-TM) is an inherited hemoglobinopathy caused by a quantitative defect in the synthesis of β-globin chains of hemoglobin, leading to the accumulation of free a-globin chains that aggregate and cause ineffective erythropoiesis. We have previously demonstrated that terminal erythroid maturation requires a transient activation of caspase-3 and that the chaperone Heat Shock Protein 70 (HSP70) accumulates in the nucleus to protect GATA-1 transcription factor from caspase-3 cleavage. This nuclear accumulation of HSP70 is inhibited in human β-TM erythroblasts due to HSP70 sequestration in the cytoplasm by free a-globin chains, resulting in maturation arrest and apoptosis. Likewise, terminal maturation can be restored by transduction of a nuclear-targeted HSP70 mutant. Here we demonstrate that in normal erythroid progenitors, HSP70 localization is regulated by the exportin-1 (XPO1), and that treatment of β-thalassemic erythroblasts with an XPO1 inhibitor increased the amount of nuclear HSP70, rescued GATA-1 expression and improved terminal differentiation, thus representing a new therapeutic option to ameliorate ineffective erythropoiesis of β-TM.

Ethical issues related to the COVID-19 pandemic in patients with cancer: experience and organisations in a French comprehensive cancer centre

BACKGROUND

The COVID-19 pandemic has aggressively reached the most vulnerable, not only the elderly but also patients with chronic conditions such as cancer. In this study, we present the outlines of ethical thinking and the measures implemented to try to respect our basic values of care, in the specific environment of an oncology hospital.

METHODS

Our ethics committee created an ethical watch system based on 24/7 shifts to assist practitioners in their daily decisions. We discuss the challenges faced by patients with cancer during the pandemic, such as access to critical care and ethical dilemmas in the context of resource scarcity, as well as the issue of isolation of patients. We also debate the restrictions in access to oncology care in a health context strongly 'prioritised' against COVID-19.

RESULTS

In all areas of an ethical dilemma, either for sorting out access to critical care or for the dramatic consequences of prolonged isolation of patients, our common thread was our attempt to protect, whenever possible, the principles of deontological ethics by strictly resisting utilitarian pressure. Respecting democratic health decision-making processes is a cornerstone of ethically relevant decisions, including in the context of a sanitary crisis.

CONCLUSION

The role of an ethics committee related to real-life situations includes not only a reflexive perspective in respect of fundamental principles, but also the help to enlighten and resolve ethical dilemmas in complex clinical situations. This ethical watch team assists physicians in decision-making, promoting the supportive and palliative dimension of care with a holistic approach.

Clonal haematopoiesis is increased in early onset in systemic sclerosis

Objectives

SSc is an autoimmune disease characterized by fibrosis, microangiopathy and immune dysfunctions including dysregulation of proinflammatory cytokines. Clonal haematopoiesis of indeterminate potential (CHIP) is defined by the acquisition of somatic mutations in haematopoietic stem cells leading to detectable clones in the blood. Recent data have shown a higher risk of cardiovascular disease in patients with CHIP resulting from increased production of proinflammatory cytokines and accelerated atherosclerosis. Eventual links between CHIP and autoimmune diseases are undetermined. The aim of our study was to evaluate the prevalence of CHIP in SSc patients and its association with clinical phenotype.

Methods

Forty-one genes frequently mutated in myeloid malignancies were sequenced in peripheral blood mononuclear cells from 90 SSc patients and 44 healthy donors.

Results

A total of 15 somatic variants were detected in 13/90 SSc patients (14%) and four somatic variants in 4/44 (9%) healthy donors (HD) (P = 0.58). The prevalence of CHIP was significantly higher in younger SSc patients than in HD: 25% (6/24) vs 4% (1/26) (P = 0.045) under 50 years and 17% (7/42) vs 3% (1/38) (P = 0.065) under 60 years. The prevalence of CHIP in patients over 70 years was similar in SSc patients and healthy donors. The most common mutations occurred in DNMT3A (seven variants). No major clinical differences were observed between SSc patients with or without CHIP.

Conclusion

Whether CHIP increases the risk to develop SSc or is a consequence of a SSc-derived modified bone marrow micro-environment remains to be explored.

Vasculitis associated with myelodysplastic syndrome and chronic myelomonocytic leukemia: French multicenter case-control study

INTRODUCTION

Our objective was to evaluate characteristics, treatment and outcome of vasculitis associated with myelodysplastic syndrome (MDS) and chronic myelomonicytic leukemia (CMML) PATIENTS AND METHODS: Retrospective descriptive analysis of MDS/CMML-related vasculitis and comparison with MDS/CMML patients without dysimmune features.

RESULTS

Seventy patients with vasculitis and MDS/CMML were included, with median age of 71.5 [21-90] years and male/female ratio of 2.3. Vasculitis was diagnosed prior to MDS/CMML in 31 patients (44%), and after in 20 patients. In comparison with MDS/CMML without autoimmune/inflammatory features, vasculitis with MDS/MPN showed no difference in MDS/CMML subtypes distribution nor International Prognostic Scoring System and CMML-specific prognostic (IPSS/CPSS) scores. Vasculitis subtypes included Giant cell arteritis in 24 patients (34%), Behçet's-like syndrome in 11 patients (20%) and polyarteritis nodosa in 6 patients (9%). Glucocorticoids (GCs) were used as first-line therapy for MDS/CMML vasculitis in 64/70 patients (91%) and 41 (59%) received combined immunosuppressive therapies during the follow-up. After a median follow-up of 33.2 months [1-162], 31 patients (44%) achieved sustained remission. At least one relapse occurred in 43 patients (61%). Relapse rates were higher in patients treated with conventional Disease Modifying Anti-Rheumatic Drug (DMARDs) (odds ratio 4.86 [95% CI 1.38 - 17.10]), but did not differ for biologics (odds ratio 0.59 [95% CI 0.11-3.20]) and azacytidine (odds ratio 1.44 [95% CI 0.21-9.76]) than under glucocorticoids. Overall survival in MDS/CMML vasculitis was not significantly different from MDS/CMML patients without autoimmune/inflammatory features (p = 0.5), but acute leukemia progression rates were decreased (log rank <0.05).

CONCLUSION

This study shows no correlation of vasculitis diagnoses with subtypes and severity of MDS/CMML, and no significant impact of vasculitis on overall survival. Whereas conventional DMARDs seem to be less effective, biologics or azacytidine therapy could be considered for even low-risk MDS/CMML vasculitis.

A Mixed-Surface Polyamidoamine Dendrimer for In Vitro and In Vivo Delivery of Large Plasmids

Drug delivery to the brain is highly hindered by the presence of the blood-brain barrier (BBB), which prevents the entry of many potential drugs/biomolecules into the brain. One of the current strategies to achieve gene therapy for neurodegenerative diseases involves direct injection of a viral vector into the brain. There are various disadvantages of viral vectors, including limitations of cargo size and safety concerns. Nanomolecules, such as dendrimers, serve as an excellent alternative to viral delivery. In this study, as proof-of-concept, we used a surface-modified dendrimer complex and delivered large plasmids to cells in vitro and in vivo in healthy rats via intracranial injection. The dendrimers were biodegradable by chemicals found within cells and toxicity assays revealed that the modified dendrimers were much less toxic than unmodified amine-surface dendrimers. As mentioned in our previous publication, these dendrimers with appropriately modified surfaces are safe, can deliver large plasmids to the brain, and can overcome the cargo size limitations associated with viral vectors. The biocompatibility of this dendritic nanomolecule and the ability to finely tune its surface chemistry provides a gene delivery system that could facilitate future in vivo cellular reprograming and other gene therapies.