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1.
J Exp Med ; 218(5)2021 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-33783474

RESUMO

Antibodies to double-stranded DNA (dsDNA) are prevalent in systemic lupus erythematosus (SLE), particularly in patients with lupus nephritis, yet the nature and regulation of antigenic cell-free DNA (cfDNA) are poorly understood. Null mutations in the secreted DNase DNASE1L3 cause human monogenic SLE with anti-dsDNA autoreactivity. We report that >50% of sporadic SLE patients with nephritis manifested reduced DNASE1L3 activity in circulation, which was associated with neutralizing autoantibodies to DNASE1L3. These patients had normal total plasma cfDNA levels but showed accumulation of cfDNA in circulating microparticles. Microparticle-associated cfDNA contained a higher fraction of longer polynucleosomal cfDNA fragments, which bound autoantibodies with higher affinity than mononucleosomal fragments. Autoantibodies to DNASE1L3-sensitive antigens on microparticles were prevalent in SLE nephritis patients and correlated with the accumulation of cfDNA in microparticles and with disease severity. DNASE1L3-sensitive antigens included DNA-associated proteins such as HMGB1. Our results reveal autoantibody-mediated impairment of DNASE1L3 activity as a common nongenetic mechanism facilitating anti-dsDNA autoreactivity in patients with severe sporadic SLE.

3.
J Allergy Clin Immunol ; 147(4): 1217-1225, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33556464

RESUMO

BACKGROUND: IL-1 plays a pivotal role in the inflammatory response during cytokine storm syndromes. OBJECTIVE: Our aim was to analyze the efficacy and safety of early anti-inflammatory treatment (AIT) with intravenous anakinra with or without glucocorticoids in coronavirus disease 2019 (COVID-19) pneumonia. METHODS: We performed a retrospective single-center cohort study of patients admitted for COVID-19 pneumonia from February 26 to April 29, 2020, to assess the efficacy of early AIT with intravenous anakinra (100 mg every 8 hours for 3 days, with tapering) alone or in combination with a glucocorticoid (intravenous methylprednisolone, 1-2 mg/kg daily, with tapering). The standard of care (SOC) treatment was hydroxychloroquine and/or azithromycin with or without antivirals and anticoagulants. Late rescue AIT with anakinra or tocilizumab was also evaluated. Treatment effect on overall survival was assessed by a propensity score-adjusted Cox model. RESULTS: A total of 128 patients were analyzed; 63 patients received early AIT (30 received anakinra alone and 33 received anakinra plus a glucocorticoid) at admission, and 65 patients did not receive early AIT and were used as controls; of the latter 65 patients, 44 received the SOC treatment alone and 21 received the SOC treatment plus late rescue AIT. After adjustment for all the unbalanced baseline covariates, early AIT reduced the hazard of mortality by 74% (adjusted hazard ratio [HR] = 0.26; P < .001). The effect was similar in patients receiving anakinra alone (adjusted HR = 0.28; P = .04) and anakinra plus a glucocorticoid (adjusted HR = 0.33; P = .07). Late rescue treatment did not show a significant advantage over SOC treatment alone (adjusted HR = 0.82; P = .70). CONCLUSIONS: This study suggests, on a larger series of patients with COVID-19 pneumonia, the potential efficacy and safety of the early use of high doses of intravenous anakinra with or without glucocorticoids.

4.
Artigo em Inglês | MEDLINE | ID: mdl-33410495

RESUMO

OBJECTIVE: Mevalonic aciduria (MA) represents the most severe of mevalonate kinase deficiency (MKD). Patients with MA have an incomplete response even to high doses of anti-cytokine drugs as anakinra or canakinumab and stem cell transplantation (SCT) represents a possible therapy for this severe disease. METHODS: We report the first two children affected by severe MKD who received haploidentical (haplo) α/ß T cell and B cell depleted SCT. Both patients received treosulfan based conditioning regimen and one received a second haplo-SCT for secondary rejection of the first. RESULTS: Both patients obtained a stable full donor engraftment with a complete regression of clinical and biochemical inflammatory signs, without acute organ toxicity or acute and chronic GvHD. In both, the urinary excretion of mevalonic acid remained high in post transplant in the absence of any inflammatory signs. CONCLUSION: Haploidentical α/ß T cell and B cell depleted SCT represents a potential curative strategy in patients affected by MKD. The persistence of urinary excretion of mevalonic acid after SCT, probably related to the ubiquitous expression of MVK enzyme, suggests that these patients should be carefully monitored after SCT to exclude MKD clinical recurrence. Prophylaxis with anakinra in the acute phase after transplant could represent a safe and effective approach. Further biological studies are required to clarify the pathophysiology of inflammatory attacks in MKD in order to better define the therapeutic role of SCT.

5.
Org Lett ; 23(3): 902-907, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33417460

RESUMO

A novel synthesis of C(2)-modified peptide nucleic acids (PNAs) is proposed, using a submonomeric strategy with minimally protected building blocks, which allowed a reduction in the required synthetic steps. N(3)-unprotected, d-Lys- and d-Arg-based backbones were used to obtain positively charged PNAs with high optical purity, as inferred from chiral GC measurements. "Chiral-box" PNAs targeting the G12D point mutation of the KRAS gene were produced using this method, showing improved sequence selectivity for the mutated- vs wild-type DNA strand with respect to unmodified PNAs.

6.
Artigo em Inglês | MEDLINE | ID: mdl-33351137

RESUMO

OBJECTIVES: Circulating anti-ENO1 and anti-H2A IgG2 have been identified as specific signatures of LN in a cross-over approach. We sought to show whether the same antibodies identify selected population of patients with LN with potentially different clinical outcomes. METHODS: Here we report the prospective analysis over 36 months of circulating IgG2 levels in patients with newly diagnosed LN (n=91) and SLE (n=31) and in other patients with SLE recruited within 2 years from diagnosis (n=99). Anti-podocyte (ENO1), anti-nucleosome (DNA, histone 2 A, histone 3) and anti-circulating proteins (C1q, AnnexinA1-ANXA1) IgG2 antibodies were determined by home-made techniques. RESULTS: LN patients were the main focus of the study. Anti-ENO1, anti-H2A and anti-ANXA1 IgG2 decreased in parallel to proteinuria and normalized within 12 months in the majority of patients while anti-dsDNA IgG2 remained high over the 36 months. Anti-ENO1 and anti-H2A had the highest association with proteinuria (Heat Map) and identified the highest number of patients with high proteinuria (68% and 71% respectively) and/or with reduced estimated glomerula filtration rate (eGFR) (58% for both antibodies) compared with 23% and 17% of anti-dsDNA (agreement analysis). Anti-ENO1 positive LN patients had higher proteinuria than negative patients at T0 and presented the maximal decrement within 12 months. CONCLUSIONS: Anti-ENO1, anti-H2A and anti-ANXA1 antibodies were associated with high proteinuria in LN patients and Anti-ENO1 also presented the maximal reduction within 12 months that paralleled the decrease of proteinuria. Anti-dsDNA were not associated with renal outcome parameters. New IgG2 antibody signatures should be utilized as tracers of personalized therapies in LN. TRIAL REGISTRATION: The Zeus study was registered at https://clinicaltrials.gov (study number: NCT02403115).

7.
Artigo em Inglês | MEDLINE | ID: mdl-33374003

RESUMO

OBJECTIVES: Serum anti-dsDNA and anti-nucleosome IgGs have been proposed as signatures for SLE and LN in limited numbers of patients. We sought to show higher sensitivity and specificity of the same antibodies with the IgG2 isotype and included IgG2 antibodies vs specific intracellular antigens in the analysis. METHODS: A total of 1052 SLE patients with (n = 479) and without (n = 573) LN, recruited at different times from the beginning of symptoms, were included in the study. Patients with primary APS (PAPS, n = 24), RA (RA, n = 24) and UCTD (UCTD, n = 96) were analysed for comparison. Anti-nucleosome (dsDNA, Histone2A, Histone3), anti-intracellular antigens (ENO1), anti-annexin A1 and anti-C1q IgG2 were determined by non-commercial techniques. RESULTS: The presence in the serum of the IgG2 panel was highly discriminatory for SLE/LN vs healthy subjects. Serum levels of anti-dsDNA and anti-C1q IgG2 were more sensitive than those of IgGs (Farr radioimmunoassay/commercial assays) in identifying SLE patients at low-medium increments. Of more importance, serum positivity for anti-ENO1 and anti-H2A IgG2 discriminated between LN and SLE (ROC T0-12 months), and high levels at T0-1 month were detected in 63% and 67%, respectively, of LN, vs 3% and 3%, respectively, of SLE patients; serum positivity for each of these was correlated with high SLEDAI values. Minor differences existed between LN/SLE and the other rheumatologic conditions. CONCLUSION: Nephritogenic IgG2 antibodies represent a specific signature of SLE/LN, with a few overlaps with other rheumatologic conditions. High levels of anti-ENO1 and anti-H2A IgG2 correlated with SLE activity indexes and were discriminatory between SLE patients limited to the renal complication and other SLE patients. TRIAL REGISTRATION: The Zeus study was registered at https://clinicaltrials.gov, NCT02403115.

8.
Artigo em Inglês | MEDLINE | ID: mdl-33217613

RESUMO

BACKGROUND: Gain-of-function mutations in STING1 underlie a type I interferonopathy termed SAVI (STING-associated vasculopathy with onset in infancy). This severe disease is variably characterized by early-onset systemic inflammation, skin vasculopathy and interstitial lung disease (ILD). OBJECTIVE: To describe a cohort of SAVI patients. METHODS: Assessment of clinical, radiological, and immunologic data from 21 patients (17 families). RESULTS: Patients carried heterozygous substitutions in STING1 previously described in SAVI, mainly the p.V155M. Most patients were symptomatic from infancy but late onset in adulthood occurred in one patient. Systemic inflammation, skin vasculopathy and ILD were observed in 19, 18 and 21 patients respectively. Extensive tissue loss occurred in 4 patients. Severity of ILD was highly variable with insidious progression up to end-stage respiratory failure reached at teenage in 6 patients. Lung imaging revealed early fibrotic lesions. Failure to thrive was almost constant, with severe growth failure seen in 4 patients. Seven patients presented polyarthritis and one infant mimicked a combined immune deficiency. Extended features reminiscent of other interferonopathies were also found e.g. intracranial calcification, glaucoma, glomerular nephropathy. Increased expression of interferon-stimulated genes and interferon α protein was constant. Autoantibodies were frequently found, in particular rheumatoid factor. Most patients presented with a T-cell defect, with low counts of memory CD8+ cells and impaired T-cell proliferation in response to antigens. Long-term follow-up described in 8 children confirmed the clinical benefice of ruxolitinib in SAVI unless the treatment is started early in the course of the disease underlying the need for early diagnosis. Tolerance was reasonably good. CONCLUSION: This largest worldwide cohort of SAVI patients precise core features and extends the clinical and immunological phenotype of the disease, displaying overlap with other monogenic interferonopathies.

9.
Pediatr Allergy Immunol ; 31 Suppl 26: 75-78, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33236427

RESUMO

COVID-19 is a complex new viral disease, in which a strict balance between anti-viral immune response and the ensuing organ inflammation has a critical role in determining the clinical course. In adults, compelling evidence exists indicating that an uncontrolled inflammatory response ("cytokine storm") is pivotal in determining disease progression and mortality. Children may rarely present with severe disease. Modulating factors related to the host's genetic factors, age-related susceptibility, and the capability to mount appropriate immune responses might play a role in control virus load at an early stage and regulating the inflammatory reaction. Elucidating these mechanisms seems crucial in developing target therapies according to patient's age, immunologic status, and disease evolution in COVID-19.

10.
Am J Hum Genet ; 107(5): 882-894, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33022220

RESUMO

Plasma DNA fragmentomics is an emerging area in cell-free DNA diagnostics and research. In murine models, it has been shown that the extracellular DNase, DNASE1L3, plays a role in the fragmentation of plasma DNA. In humans, DNASE1L3 deficiency causes familial monogenic systemic lupus erythematosus with childhood onset and anti-dsDNA reactivity. In this study, we found that human patients with DNASE1L3 disease-associated gene variations showed aberrations in size and a reduction of a "CC" end motif of plasma DNA. Furthermore, we demonstrated that DNA from DNASE1L3-digested cell nuclei showed a median length of 153 bp with CC motif frequencies resembling plasma DNA from healthy individuals. Adeno-associated virus-based transduction of Dnase1l3 into Dnase1l3-deficient mice restored the end motif profiles to those seen in the plasma DNA of wild-type mice. Our findings demonstrate that DNASE1L3 is an important player in the fragmentation of plasma DNA, which appears to act in a cell-extrinsic manner to regulate plasma DNA size and motif frequency.

12.
G Ital Dermatol Venereol ; 155(5): 590-598, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32618445

RESUMO

Type I interferonopathies are a clinically heterogeneous group of inherited disorders of the innate immune system characterized by constitutive activation of the type I interferon signaling pathway. Cutaneous vasculopathy, lipodystrophy, interstitial lung disease and brain calcifications are the typical manifestations characterizing affected patients. The pathogenic mechanism commonly underlying these disorders is the abnormal activation of immune pathways involved in recognition of non-self-oligonucleotides. These natural defenses against virus consent humans to survive the infections. Target therapies capable of inhibiting type I interferon signaling pathway seem effective in these patients, albeit with possible incomplete responses and severe side effects.

13.
Eur J Immunol ; 2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32707604

RESUMO

Adenosine deaminase 2 deficiency (DADA2) is an autoinflammatory disease characterized by inflammatory vasculopathy, early strokes associated often with hypogammaglobulinemia. Pure red cell aplasia, thrombocytopenia, and neutropenia have been reported. The defect is due to biallelic loss of function of ADA2 gene, coding for a protein known to regulate the catabolism of extracellular adenosine. We therefore investigated immune phenotype and B- and T-cell responses in 14 DADA2 patients to address if ADA2 mutation affects B- and T-cell function. Here, we show a significant decrease in memory B cells, in particular class switch memory, and an expansion of CD21low B cells in DADA2 patients. In vitro stimulated B lymphocytes were able to secrete nonfunctional ADA2 protein, suggesting a cell intrinsic defect resulting in an impairment of B-cell proliferation and differentiation. Moreover, CD4+ and CD8+ T cells were diminished; however, the frequency of circulating T follicular helper cells was significantly increased but they had an impairment in IL-21 production possibly contributing to an impaired B cell help. Our findings suggest that ADA2 mutation could lead to a B-cell intrinsic defect but also to a defective Tfh cell function, which could contribute to the immunodeficient phenotype reported in DADA2 patients.

15.
Vaccines (Basel) ; 8(2)2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32423059

RESUMO

As the outbreak of the new coronavirus (SARS-CoV-2) infection is spreading globally, great effort is being made to understand the disease pathogenesis and host factors that predispose to disease progression in an attempt to find a window of opportunity for intervention. In addition to the direct cytopathic effect of the virus, the host hyper-inflammatory response has emerged as a key factor in determining disease severity and mortality. Accumulating clinical observations raised hypotheses to explain why some patients develop more severe disease while others only manifest mild or no symptoms. So far, Covid-19 management remains mainly supportive. However, many researches are underway to clarify the role of antiviral and immunomodulating drugs in changing morbidity and mortality in patients who become severely ill. This review summarizes the current state of knowledge on the interaction between SARS-CoV-2 and the host immune system and discusses recent findings on proposed pharmacologic treatments.

16.
Arthritis Rheumatol ; 72(7): 1059-1063, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32293098

RESUMO

Poor outcomes in COVID-19 correlate with clinical and laboratory features of cytokine storm syndrome. Broad screening for cytokine storm and early, targeted antiinflammatory therapy may prevent immunopathology and could help conserve limited health care resources. While studies are ongoing, extrapolating from clinical experience in cytokine storm syndromes may benefit the multidisciplinary teams caring for patients with severe COVID-19.


Assuntos
Anti-Inflamatórios/uso terapêutico , Infecções por Coronavirus/imunologia , Síndrome da Liberação de Citocina/tratamento farmacológico , Síndrome da Liberação de Citocina/virologia , Pneumonia Viral/imunologia , Betacoronavirus , Biomarcadores , Infecções por Coronavirus/complicações , Infecções por Coronavirus/terapia , Síndrome da Liberação de Citocina/diagnóstico , Intervenção Médica Precoce , Humanos , Pandemias , Pneumonia Viral/complicações , Pneumonia Viral/terapia
17.
J Allergy Clin Immunol ; 146(2): 429-437, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32169379

RESUMO

BACKGROUND: X-linked agammaglobulinemia (XLA) is the prototype of primary humoral immunodeficiencies. Long-term follow-up studies regarding disease-related complications and outcome are scarce. OBJECTIVE: Our aim was to describe the natural history of XLA. METHODS: A nationwide multicenter study based on the Italian Primary Immunodeficiency Network registry was established in 2000 in Italy. Affected patients were enrolled by documenting centers, and the patients' laboratory, clinical, and imaging data were recorded on an annual base. RESULTS: Data on the patients (N = 168) were derived from a cumulative follow-up of 1370 patient-years, with a mean follow-up of 8.35 years per patient. The mean age at diagnosis decreased after establishment of the Italian Primary Immunodeficiency Network registry (84 months before vs 23 months after). Respiratory, skin, and gastrointestinal manifestations were the most frequent clinical symptoms at diagnosis and during long-term follow-up. Regular immunoglobulin replacement treatment reduced the incidence of invasive infections. Affected patients developed chronic lung disease over time (47% after 40 years of follow-up) in the presence of chronic sinusitis (84%). Malignancies were documented in a minority of cases (3.7%). Overall survival for affected patients was significantly reduced when compared with that for the healthy male Italian population, and it further deteriorated in the presence of chronic lung disease. CONCLUSIONS: This is the first detailed long-term follow-up study for patients with XLA, revealing that although immunoglobulin replacement treatment reduces the incidence of invasive infections, it does not appear to influence the development of chronic lung disease. The overall survival of affected patients is reduced. Further studies are warranted to improve patients' clinical management and increase awareness among physicians.

18.
J Exp Med ; 217(2)2020 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-31841125

RESUMO

Antibody-mediated autoimmune diseases are a major health burden. However, our understanding of how self-reactive B cells escape self-tolerance checkpoints to secrete pathogenic autoantibodies remains incomplete. Here, we demonstrate that patients with monogenic immune dysregulation caused by gain-of-function mutations in PIK3CD, encoding the p110δ catalytic subunit of phosphoinositide 3-kinase (PI3K), have highly penetrant secretion of autoreactive IgM antibodies. In mice with the corresponding heterozygous Pik3cd activating mutation, self-reactive B cells exhibit a cell-autonomous subversion of their response to self-antigen: instead of becoming tolerized and repressed from secreting autoantibody, Pik3cd gain-of-function B cells are activated by self-antigen to form plasmablasts that secrete high titers of germline-encoded IgM autoantibody and hypermutating germinal center B cells. However, within the germinal center, peripheral tolerance was still enforced, and there was selection against B cells with high affinity for self-antigen. These data show that the strength of PI3K signaling is a key regulator of pregerminal center B cell self-tolerance and thus represents a druggable pathway to treat antibody-mediated autoimmunity.


Assuntos
Formação de Anticorpos/genética , Autoanticorpos/imunologia , Classe I de Fosfatidilinositol 3-Quinases/genética , Mutação com Ganho de Função , Tolerância Imunológica/imunologia , Plasmócitos/imunologia , Animais , Autoanticorpos/sangue , Autoantígenos/imunologia , Autoimunidade/genética , Classe I de Fosfatidilinositol 3-Quinases/sangue , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Feminino , Centro Germinativo/imunologia , Humanos , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Transdução de Sinais/genética
19.
Org Biomol Chem ; 18(2): 211-214, 2020 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-31808772

RESUMO

Sulfonato-calix[n]arenes (sclxn) are promising tools to generate crystalline protein frameworks. We report, for the first time, a lower rim functionalised octa-anionic calix[4]arene (sclx4mc) in complex with proteins. Two crystal structures of sclx4mc bound to yeast or horse heart cytochrome c (cytc) are described. Highly porous honeycomb or tubular assemblies were obtained with yeast or horse cytc, respectively. Related frameworks were obtained previously with sclx8 and sclx6 but not with sclx4, suggesting that the ligand charge is a determining factor.


Assuntos
Calixarenos/química , Citocromos c/química , Fenóis/química , Porosidade , Proteínas/química , Animais , Ânions/química , Cristalização , Cristalografia por Raios X , Cavalos , Ligantes , Estrutura Molecular , Leveduras
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