BACKGROUND:The T-cell engager antibody blinatumomab (BlincytoT⁢M) represents a promising rescue therapy for relapsed/refractory CD19+ acute lymphoblastic leukemia (B-ALL), although ~20-30% of patients still do not respond to treatment. Blinatumomab creates a tight synapsis between CD3+ T-lymphocytes and leukemic CD19+ B-cells, resulting in a granzyme B (GzB)-mediated specific lysis of leukemic cells.METHODS:Aim of the study was to provide evidence that variability in blinatumomab response could have a genetic basis in PAX5, one of the most often mutated genes in B-ALL, affecting the CD19 surface expression on lymphoblasts, and could be explored in vitro by means of a cytofluorimetric assay, staining both surface antigens (CD45, CD19 and CD3) and intracytoplasmic markers (7AAD, Syto16). Two human immortalized B-ALL cell lines (NALM6 and REH) were chosen for their different PAX5 and CD19 protein levels, as verified by western blot and flow cytometry, respectively.RESULTS:In contrast to NALM6, REH cells do not express the full-length PAX5 protein and show less CD19 on the cell surface (fluorescence peak median intensity: 9155 versus 28895). Co-cultures of CD3+ T-lymphocytes from healthy donors and B-ALL cell lines were seeded at an effector-to-target cell ratio of 1:10 for simulating the condition existing in the bone marrow due to the malignant invasion of blast cells. Co-cultures were exposed in vitro to blinatumomab and the simultaneous increase in blast mortality and T-lymphocytes activation induced by the drug was observed at day +7 (both effects: p < 0.0001 versus untreated, two-way ANOVA, Bonferroni post-test), and was particularly pronounced in REH compared to NALM6 co-cultures (p < 0.05). Surprisingly, daily release of GzB in supernatants, measured by an ELISA assay, was significantly lower in drug-exposed REH co-cultures compared to NALM6 at early time-points (days +3 and +4, p-value < 0.0001, three-way ANOVA), reaching a comparable plateau only towards the end of the incubation period (at day +5). Only 2 out of 5 primary co-cultures of leukemic and mononuclear cells isolated from bone marrow aspirates of B-ALL patients (age: median 10.7 years, interquartile range (IQR) 3.4; males: 60%) responded to the drug in vitro (simultaneous blast mortality and T-lymphocyte activation: both effects: p < 0.0001 versus untreated) and at different drug concentrations. Results were unrelated to the percentages of immature CD19+ B-cells in the diagnostic samples.CONCLUSIONS:In conclusion, cytofluorimetric analysis can highlight the different response induced by blinatumomab among co-cultures. Whether and how this difference is affected by PAX5-regulated CD19 expression is unclear and whether it is predictive of in vivo response to therapy remains to be established. Further dedicated studies are required to investigate these issues in detail.

Background: Acyclovir represents the first-line prophylaxis and therapy for herpes virus infections. However, its pharmacokinetics in children exposes them to the risk of ineffective or toxic concentrations. The study was aimed at investigating the population pharmacokinetics (POP/PK) of intravenous (IV) acyclovir in oncologic children.Methods: Patients (age, 8.6 ± 5.0 years, 73 males and 47 females) received IV acyclovir for prophylaxis (n = 94) and therapy (n = 26) under a therapeutic drug monitoring (i.e., minimum and maximal plasma concentrations, >0.5 and <25 mg/L, respectively). Plasma concentrations were fitted by nonlinear mixed effect modeling and a simulation of dosing regimens was performed. Findings were stratified according to an estimated glomerular filtration rate (eGFR) threshold of 250 ml/min/1.73 m2.Results: The final 1-compartment POP/PK model showed that eGFR had a significant effect on drug clearance, while allometric body weight influenced both clearance and volume of distribution. The population clearance (14.0 ± 5.5 L/h) was consistent across occasions. Simulation of standard 1-h IV infusion showed that a 10-mg/kg dose every 6 h achieved target concentrations in children with normal eGFR (i.e., ≤250 ml/min/1.73 m2). Increased eGFR values required higher doses that led to an augmented risk of toxic peak concentrations. On the contrary, simulated prolonged (i.e., 2 and 3-h) or continuous IV infusions at lower doses increased the probability of target attainment while reducing the risk of toxicities.Conclusion: Due to the variable pharmacokinetics of acyclovir, standard dosing regimens may not be effective in some patients. Prospective trials should confirm the therapeutic advantage of prolonged and continuous IV infusions

The database includes the raw data of the article “Hydroxychloroquine modulates immunological pathways activated by RNA:DNA hybrids in Aicardi–Goutières syndrome patients carrying RNASEH2 mutations”. Aim of the work was to investigate whether hydroxychloroquine (HCQ) is able to modulate the abnormal inflammatory response driven by RNA:DNA hybrids in lymphoblastoid cell lines (LCLs) of Aicardi–Goutières syndrome (AGS) patients. The database contains data obtained by the following evaluations: i) flow cytometry for the detection of cytosolic RNA:DNA hybrids accumulation; ii) Real-Time PCR for the evaluation of mRNA expression levels of IFIT1 and IFI44, two interferon-stimulated genes ISGs; and of IRF3, MYD88, IRF7 and NF-kB transcripts before and after HCQ treatment; iii) western blot analysis of proteins involved in autophagy (LC3-II/LC3-I ratio and p62) and of cGAS. We found that RNA:DNA hybrids accumulate mainly in the cytoplasm and co-localize with lysosomes in the LCL derived from an AGS patient carrying a RNASEH2B mutation, suggesting an impairment in the RNA:DNA hybrid degradation. On the other hand, the RNASEH2A-mutant LCL carries RNA:DNA hybrids in endosomes. Moreover, we evidenced that HCQ is a drug that can induce decreased activation of the IFN-α immune cascade only in the RNASEH2B-mutant LCL. Therefore, we hypothesized that HCQ, a European Medicines Agency-approved drug, may be effective in the treatment for AGS mainly when there is an abnormal activation of the innate immune response.

RASopathies and mTORopathies are groups of genetic syndromes associated with increased activation of the RAS-MAPK or the PI3K-AKT-mTOR pathway, resulting in altered cell proliferation during embryonic and postnatal development. The RAS-MAPK and the PI3K-AKT-mTOR pathways are connected to each other and play a crucial role in adaptive immunity. However, with the exception of Activated PI3K delta syndrome (APDS), immune function has not been deeply studied in these disorders. We collected clinical and immunophenotypic data of a cohort of patients with RASopathies and mTORopathies. Overall, we enrolled 47 patients (22 females, 25 males, age 2–40 years): 33 with neurofibromatosis type 1, 11 Noonan syndrome and 3 Bannayan-Riley-Ruvalcaba syndrome. 8 patients reported a history of invasive infections requiring hospitalization and intravenous antibiotic therapy. Only 3 patients reported a history of unusual, difficult-to-treat or deep-seated infection. Adenotonsillectomy was performed in 11 patients (24%). However, in most cases (83%) patients' parents did not perceive their child as more prone to infections than their peers. Lymphocyte subpopulations were analyzed in 37 of the 47 patients (16 female, 21 males, age 1–40 years). Among the studied lymphocyte subsets, the only consistent alteration regarded an increased percentage of immature B cells (recent bone marrow emigrants) in 34 out of 37 (91,9%) patients, and an increased percentage of double negative T cells in 9 patients. In conclusion, although borderline immune abnormalities were present in a significant proportion of subjects and adenotonsillectomy was performed more frequently than expected for the general population, no major immune disturbance was found in this cohort of patients.

Primary immunodeficiencies (PIDs) are a large and growing group of disorders commonly associated with recurrent infections. However, nowadays, we know that PIDs often carry with them consequences related to organ or hematologic autoimmunity, autoinflammation, and lymphoproliferation in addition to simple susceptibility to pathogens. Alongside this conceptual development, there has been technical advancement, given by the new but already established diagnostic possibilities offered by new genetic testing (e.g., next-generation sequencing). Nevertheless, there is also the need to understand the large number of gene variants detected with these powerful methods. That means advancing beyond genetic results and resorting to the clinical phenotype and to immunological or alternative molecular tests that allow us to prove the causative role of a genetic variant of uncertain significance and/or better define the underlying pathophysiological mechanism. Furthermore, because of the rapid availability of results, laboratory immunoassays are still critical to diagnosing many PIDs, even in screening settings. Fundamental is the integration between different specialties and the development of multidisciplinary and flexible diagnostic workflows. This paper aims to tell these evolving aspects of immunodeficiencies, which are summarized in five key messages, through introducing and exemplifying five clinical cases, focusing on diseases that could benefit targeted therapy.

Background: The extent to which prenatal low-level mercury (Hg) exposure through maternal fish intake and heavy metals exposure affect children’s neurodevelopment is controversial and may appear in the long term. In 2007, a prospective cohort, the Northern Adriatic Cohort II (NAC-II), was established to investigate the association between prenatal Hg exposure from maternal fish consumption and child neurodevelopment. The study enrolled 900 pregnant women, and 632 and 470 children underwent neurodevelopmental evaluation at 18 and 40 months of age, respectively. The NAC-II cohort is a part of the Mediterranean cohort in the “Public health impact of long-term, low-level, mixed element exposure in susceptible population strata” project. Methods: This protocol describes the follow-up assessment of the effects of prenatal low level Hg and other heavy metals exposure on the developing nervous system of the children born within the NAC-II who reached the age of 7 years. Child diet components are estimated through a Diet Diary. Child hair and urine are collected for determination of Hg level. In addition, levels of other potentially neurotoxic metals, namely Manganese, Cadmium, Lead, Arsenic, and Selenium, are also measured in the same matrices. Discussion: This protocol extends to the first years of schooling age the evaluation of the neurotoxicant effect of Mercury and of the other heavy metals on children’s neurodevelopment, adjusting for the potential confounders, such as the lifestyles and social economic status of children’s families. Longitudinal analysis of neurodevelopment, assessed in different ages (18 months, 40 months, and 7 years), are performed.

The development of vaccines to prevent SARS-CoV-2 infection has mainly relied on the induction of neutralizing antibodies (nAbs) to the Spike protein of SARS-CoV-2, but there is growing evidence that T cell immune response can contribute to protection as well. In this study, an anti-receptor binding domain (RBD) antibody assay and an INFγ-release assay (IGRA) were used to detect humoral and cellular responses to the Pfizer-BioNTech BNT162b2 vaccine in three separate cohorts of COVID-19-naïve patients: 108 healthcare workers (HCWs), 15 elderly people, and 5 autoimmune patients treated with immunosuppressive agents. After the second dose of vaccine, the mean values of anti-RBD antibodies (Abs) and INFγ were 123.33 U/mL (range 27.55–464) and 1513 mIU/mL (range 145–2500) in HCWs and 210.7 U/mL (range 3–500) and 1167 mIU/mL (range 83–2500) in elderly people. No correlations between age and immune status were observed. On the contrary, a weak but significant positive correlation was found between INFγ and anti-RBD Abs values (rho = 0.354, p = 0.003). As to the autoimmune cohort, anti-RBD Abs were not detected in the two patients with absent peripheral CD19+B cells, despite high INFγ levels being observed in all 5 patients after vaccination. Even though the clinical relevance of T cell response has not yet been established as a correlate of vaccine-induced protection, IGRA testing has showed optimal sensitivity and specificity to define vaccine responders, even in patients lacking a cognate antibody response to the vaccine.

Mitoquinone (MitoQ) is a mitochondrial reactive oxygen species scavenger that is characterized by high bioavailability. Prior studies have demonstrated its neuroprotective potential. Indeed, the release of reactive oxygen species due to damage to mitochondrial components plays a pivotal role in the pathogenesis of several neurodegenerative diseases. The present study aimed to examine the impact of the inflammation platform activation on the neuronal cell line (DAOY) treated with specific inflammatory stimuli and whether MitoQ addition can modulate these deregulations. DAOY cells were pre-treated with MitoQ and then stimulated by a blockade of the cholesterol pathway, also called mevalonate pathway, using a statin, mimicking cholesterol deregulation, a common parameter present in some neurodegenerative and autoinflammatory diseases. To verify the role played by MitoQ, we examined the expression of genes involved in the inflammation mechanism and the mitochondrial activity at different time points. In this experimental design, MitoQ showed a protective effect against the blockade of the mevalonate pathway in a short period (12 h) but did not persist for a long time (24 and 48 h). The results obtained highlight the anti-inflammatory properties of MitoQ and open the question about its application as an effective adjuvant for the treatment of the autoinflammatory disease characterized by a cholesterol deregulation pathway that involves mitochondrial homeostasis.

Aicardi-Goutières syndrome (AGS) is a rare genetic disease caused by mutations in nine genes that are all involved in nucleic acid metabolism or sensing. 1,2The three RNASEH2 subunits represent the most frequently mutated genes in AGS patients, 1,3 and mutations in RNASEH2 subunits lead to the accumulation of endogenous RNA:DNA hybrids that may trigger an interferon-αmediated immune response 4 through the activation of pattern recognition receptors (PRRs). 5PRRs perform surveillance on extracellular, endosomal, and cytosolic compartments to identify signs of infection: endogenous nucleic acids that are inappropriately cleared may enter and accumulate in the cytoplasm, driving inflammation and autoimmune diseases. 6This accumulation may be the cause of the clinical autoimmune phenotype of AGS patients carrying RNASEH2 mutations.A proven effective cure for AGS has not been discovered, and targeting these two pathways may lead to a treatment that improves patients' immunological symptoms.Hydroxychloroquine (HCQ) interferes with normal antigen processing and presentation and is widely used in the clinical treatment of autoimmune diseases such as systemic lupus erythematosus and rheumatoid arthritis. 7HCQ is also a wellknown inhibitor of autophagy that prevents the degradation of autolysosomes.This drug inhibits acidification and maturation of endosomes and increases the pH in lysosomes, resulting in the inhibition of their main functions, such as downstream cell signaling through TLRs. 7Therefore, the aim of our work was to investigate whether HCQ is able to modulate the abnormal inflammatory response driven by RNA:DNA hybrids.Considering the noteworthy difficulties in obtaining primary cells from children affected by this rare disease, we used immortalized lymphoblastoid cell lines (LCLs): one from a patient carrying the RNASEH2A p.R108W + p.F230L mutations, one from a patient carrying the RNASEH2B p.A177T mutation and one from a healthy control.We investigated the presence of RNA:DNA hybrids using the S9.6 antibody and flow cytometry.Quantification of the mean S9.6 fluorescence revealed a significant increase in RNA:DNA hybrids only in the RNASEH2B-mutant LCL (Fig. S1A).RNA:DNA hybrids were primarily localized in the cytoplasm in all three cell

During COVID-19 outbreak, a large number of children with severe inflammatory disease has been reported. This condition, named Pediatric Multi-inflammatory Syndrome temporally associated with COVID-19 (PIMS-TS) or Multisystem Inflammatory Syndrome associated with Coronavirus Disease 2019 (MIS-C), shares some clinical features with Kawasaki disease and is frequently complicated by myocarditis or shock. It has been suggested that MIS-C belongs to the group of cytokine storm syndromes triggered by SARS-CoV-2 infection. So far, intravenous immunoglobulin (IVIG) and systemic glucocorticoids are the most common therapeutic approaches reported in this group of patients. However, the use of anakinra in patients with severe forms of COVID-19 is showing promising results. Here we reported two patients with multisystem inflammatory syndrome complicated with shock. Both the patients presented a poor response to IVIG and systemic glucocorticoids and received anakinra. Treatment with IL-1 receptor antagonist showed a rapid improvement of clinical conditions and biochemical analysis in both patients and demonstrated a good safety profile. Thus, we look forward for future controlled clinical trials with the aim to demonstrate the effectiveness of anakinra in patients with MIS-C and established precise criteria for its use.

Cytoplasmic nucleic acids sensing through cGAS-STING-TBK1 pathway is crucial for the production of antiviral interferons (IFNs). IFN production can also be induced by lipopolysaccharide (LPS) stimulation through Toll-like receptor 4 (TLR4) in appropriate conditions. Of note, both IFN production and dysregulated LPS-response could play a role in the pathogenesis of Systemic Lupus Erythematosus (SLE). Indeed, LPS can trigger SLE in lupus-prone mice and bacterial infections can induce disease flares in human SLE. However, the interactions between cGAS and TLR4 pathways to IFNs have been poorly investigated. To address this issue, we studied LPS-stimulation in cellular models with a primed cGAS-STING-TBK1 pathway. cGAS-stimulation was naturally sustained by undigested self-nucleic acids in fibroblasts from DNase2-deficiency interferonopathy, whilst it was pharmacologically obtained by cGAMP-stimulation in THP1 cells and murine bone marrow-derived dendritic cells. We showed that cells with a primed cGAS-STING-TBK1 pathway displayed enhanced IFNs production after TLR4-challenge. STING-inhibition did not affect IFN production after LPS alone, but prevented the amplified IFN production in cGAMP-primed cells, suggesting that functional STING is required for priming-dependent enhancement. Furthermore, we speculated that an increased PIK3AP1 expression in DNase2-deficient fibroblasts may link cGAMP-priming with increased LPS-induced IFN production. We showed that both the hyper-expression of PIK3API and the enhanced LPS-induced IFN production can be contrasted by STING inhibitors. Our results may explain how bacterial LPS can synergize with cGAS-pathway in promoting the development of SLE-like autoimmunity.

Ataxia telangiectasia (AT) and Aicardi–Goutières syndrome (AGS) are inherited disorders of immunity with prevalent neurological phenotype. Available treatments are only partially effective, and the prognosis is poor. Induced pluripotent stem cells (iPSCs) are obtained by reprogramming patient somatic cells, preserving the donor individual genetic heritage and creating patient‐specific disease models, useful to investigate pathogenesis and drug effects and to develop precision therapies. The aim is to investigate the cytotoxicity of a panel of immunomodulators using iPSCs of patients with AT or different forms of AGS (AGS1, AGS2, and AGS7). iPSCs were obtained by reprogramming AT and AGS patients’ cells and, as a control, the BJ normal human fibroblast line, using Sendai virus. Cytotoxic effects of two drugs proposed to treat respectively AT and AGS (dexamethasone and mepacrine) were tested by the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay after 72 hours' exposure. Data were obtained also for other immunomodulatory drugs (thioguanine, mercaptopurine, thalidomide, and lenalidomide). Relative expression of genes involved in the tested drug pathways was analyzed. AGS7‐derived iPSCs displayed altered viability when treated with a low dose of mepacrine and higher expression of cyclic guanosine monophosphate–adenosine monophosphate synthase, which is the main target for mepacrine action. AGS7‐derived iPSCs were also more sensitive to thioguanine, while AGS2 and AT iPSCs were less sensitive to this medication than the BJ‐iPSC. All iPSCs were equally sensitive to mercaptopurine and resistant to dexamethasone, thalidomide, and lenalidomide. This work establishes an innovative in vitro model that is useful to investigate the mechanisms of drugs potentially effective in AT and AGS.

BACKGROUND:Pulmonary arterial hypertension consists in an increase of mean pulmonary arterial pressure (PAPm ≥ 25 mmHg), and may lead to right ventricular failure. Pulmonary arterial hypertension can arise in several disorders, encompassing inflammatory conditions and connective tissue diseases. The occurrence of pulmonary arterial hypertension has recently been reported in monogenic interferonopathies and in systemic lupus erythematosus, highlighting the pathogenic role of type I interferons and paving the way to therapies aimed at inhibiting interferon signaling.CASE:We describe a 17-year-old boy with DNase II deficiency, presenting a clinical picture with significant overlap with systemic lupus erythematosus. During treatment with the Janus kinase inhibitor ruxolitinib, he developed pulmonary arterial hypertension, raising the question whether it could represent a sign of insufficient disease control or a drug-related adverse event. The disease even worsened after drug withdrawal, but rapidly improved after starting the drug again at higher dosage.SUMMARY AND CONCLUSION:Pulmonary arterial hypertension can complicate type I interferonopathies. We propose that ruxolitinib was beneficial in this case, but the wider role of Janus kinase inhibitors for the treatment of pulmonary arterial hypertension is not clear. For this reason, a strict cardiologic evaluation must be part of the standard care of subjects with interferonopathies, especially when Janus kinase inhibitors are prescribed.

Interferon-stimulated genes (ISGs) are a set of genes whose transcription is induced by interferon (IFN). The measure of the expression of ISGs enables calculating an IFN score, which gives an indirect estimate of the exposition of cells to IFN-mediated inflammation. The measure of the IFN score is proposed for the screening of monogenic interferonopathies, like the Aicardi-Goutières syndrome, or to stratify subjects with systemic lupus erythematosus to receive IFN-targeted treatments. Apart from these scenarios, there is no agreement on the diagnostic value of the score in distinguishing IFN-related disorders from diseases dominated by other types of cytokines. Since the IFN score is currently measured in several research hospitals, merging experiences could help define the potential of scoring IFN inflammation in clinical practice. However, the IFN score calculated at different laboratories may be hardly comparable due to the distinct sets of IFN-stimulated genes assessed and to different controls used for data normalization. We developed a reliable approach to minimize the inter-laboratory variability, thereby providing shared strategies for the IFN signature analysis and allowing different centers to compare data and merge their experiences.

The balance of autophagy, apoptosis and necroptosis is crucial to determine the outcome of the cellular response to cholesterol dysregulation. Cholesterol plays a major role in regulating the properties of cell membranes, especially as regards their fluidity, and the regulation of its biosynthesis influences the shape and functions of these membranes. Whilst dietary cholesterol can easily be distributed to most organs, the central nervous system, whose membranes are particularly rich in cholesterol, mainly relies on de novo synthesis. For this reason, defects in the biosynthesis of cholesterol can variably affect the development of central nervous system. Moreover, defective synthesis of cholesterol and its intermediates may reflect both on structural cell anomalies and on the response to inflammatory stimuli. Examples of such disorders include mevalonate kinase deficiency, and Smith-Lemli-Opitz syndrome, due to deficiency in biosynthetic enzymes, and type C Niemann-Pick syndrome, due to altered cholesterol trafficking across cell compartments. Autophagy, as a crucial pathway dedicated to the degradation of cytosolic proteins and organelles, plays an essential role in the maintenance of homeostasis and in the turnover of the cytoplasmic material especially in the presence of imbalances such as those resulting from alteration of cholesterol metabolism. Manipulating the process of autophagy can offer possible strategies for improving neuronal cell viability and function in these genetic disorders.

Most of primary immunodeficiencies with hypogammaglobulinemia are associated with reduced memory B cells. T cell development may be interesting as well, but increased recent thymic emigrants are rarely reported in these patients. We report the case of a family (mother and her two sons) diagnosed with common variable immunodeficiency 10 due to a mutation in the NFKB2 gene. Laboratory findings showed that all three patients presented hypogammaglobulinemia, reduced memory B cells and elevated naïve T lymphocytes and recent thymic emigrants. This feature, in the absence of glucocorticoid deficiency, may suggest a primary thymic dysfunction. Interestingly, the mother presented the worst immune phenotype, as regards both antibody production and NK function, indicating that immune function may deteriorate in the course of time. We conclude that close monitoring of immune functions may widen the knowledge on the CVID10 and improve the patients’ care.

Background Whole exome sequencing can allow genetic diagnosis in subjects with long lasting clinical stories not supporting any well-defined disorder. A 35-year-old man was referred to ophthalmologist’s evaluation for blurry vision in his left eye. The fundus examination showed choroidal lesions in both eyes. His past medical history was relevant for celiac disease, recurrent episodes of fever and skin rashes with leukocytoclastic vasculitis, inflammatory lesions of the osteoarticular and muscular system, one episode of aseptic meningitis, an intracranial granuloma and two episodes of anterior uveitis. He had also splenomegaly with non-caseating granulomas. Brain TC founded multiple lytic and sclerotic skull lesions. He was diagnosed with atypical sarcoidosis and treated with oral steroid and methotrexate. Laboratory data always showed elevated erythrocyte sedimentation rate, strong positive C-reactive protein and polyclonal gammopathy. Objectives To describe functional and genetic data supporting the role of a PIM1 mutation in the multisystemic inflammation and lymphoproliferation of the patient. Methods Whole exome sequencing (WES) analysis. Flow-cytometry to evaluate Pim1 expression, Bad phosphorylation (target of Pim1 kinase) and the effect of PIM inhibitor on peripheral blood mononuclear cell (PBMC) viability. RNAseq was on primary fibroblasts from the patient and from healthy donors. Cloning of the mutated gene in a vector for further functional studies. Results WES analysis revealed the de novo heterozygous missense variation c.C1132A (p.H378N) in PIM1 gene. This variation was never described in on-line database and was predicted as damaging by various bioinformatic tools. Preliminary functional investigations in fibroblasts showed normal expression of Pim1, but higher phosphorylation of BAD protein was measured in cells from the patient. Moreover, PBMC from the patient displayed a lower sensitivity to the PIM inhibitor PIM447. RNAseq showed an altered expression profile in genes involved in the extracellular matrix organization. Conclusion PIM1 is an oncogene that encodes a protein kinase and, indeed, somatic gain of function mutations can be found in cancers. Preliminary data obtained from our patient suggest a gain of function effect of the p.H378N variant. The lymphoproliferative disorder may be sustained by the anti-apoptotic action of phosphorylated BAD. Recent data correlated hyperactive PIM1 in tumors with high degree of inflammatory infiltration accompanied by NFAT and mTOR activation and IL6 expression. A role of this cytokine also in our patient was coherent with a good clinical response to a treatment with tocilizumab, targeting IL-6. Although these results are supportive of a role of mutated PIM1 in the observed phenotype, we cannot still claim that this is causative of a novel syndrome. The detection of further cases and functional studies on cells transfected with mutated PIM1 will help shedding more light on this inflammatory and lymphoproliferative disorder. Disclosure of Interests None declared