Publications by authors named "Francesco Liotta"

86 Publications

T Cell Response Toward Tissue-and Epidermal-Transglutaminases in Coeliac Disease Patients Developing Dermatitis Herpetiformis.

Front Immunol 2021 20;12:645143. Epub 2021 Apr 20.

Department of Experimental and Clinical Medicine, School of Human Health Sciences, University of Florence, Florence, Italy.

The reason why only few coeliac patients develop the cutaneous manifestation of the disease, named dermatitis herpetiformis (DH), is still unknown. Epidermal transglutaminase (TG3) has been described as the main autoantigen of humoral immunity in DH but the mechanisms leading to this autoimmune response remain obscure. Here we characterized T cells from skin, gut and peripheral blood of DH and coeliac disease (CD) patients, evaluated the impact of the gluten-free diet on circulating T lymphocytes' phenotype and investigated antigen specific T cell response toward epidermal and tissue transglutaminase (TG2). DH patients showed an increased frequency of skin-derived T cells producing TNFα when compared to CD patients. Moreover, circulating T cells producing TNFα and IL-17A positively correlated with clinical score of skin disease activity and decreased after gluten-free diet. Finally, TG2 and TG3-specific T cells resulted more reactive to antigens stimulation in DH patients and showed cross reactivity toward the two autoantigens in both the group of patients. Our data suggest a role of TNFα and IL-17A producing cells in the development of DH and, for the first time, show the existence of a crossed T cell response toward the two transglutaminases isoforms, thus suggesting new insights on T cells role in skin damage.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fimmu.2021.645143DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8093623PMC
April 2021

First-dose mRNA vaccination is sufficient to reactivate immunological memory to SARS-CoV-2 in recovered COVID-19 subjects.

J Clin Invest 2021 May 3. Epub 2021 May 3.

Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy.

The characterization of the adaptive immune response to COVID-19 vaccination in individuals who recovered from SARS-CoV-2 infection may define current and future clinical practice. To determine the effect of two doses BNT162b2 mRNA COVID-19 vaccination schedule in individuals who recovered from COVID-19 (COVID-19 recovered) compared to naïve subjects, we evaluated SARS-CoV-2 Spike-specific T and B cell responses, as well as specific IgA, IgG, IgM and neutralizing antibodies titers in 22 individuals who received BNT162b2 mRNA COVID-19 vaccine, 11 of which had a previous history of SARS-CoV-2 infection. Evaluations were performed before vaccination and then weekly until 7 days post second injection. Data obtained clearly showed that one vaccine dose is sufficient to increase both cellular and humoral immune response in COVID-19 recovered subjects without any additional improvement after the second dose. On the contrary, the second dose is proved mandatory in naïve ones to further enhance the immune response. These findings were further confirmed at serological level in a larger cohort of naïve (68) and COVID-19 recovered (29) subjects, tested up to 50 days post vaccination. These results question whether a second vaccine injection in COVID-19 recovered subjects is required and indicate that millions of vaccine doses may be redirected to naïve individuals, thus shortening the time to reach herd immunity.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1172/JCI149150DOI Listing
May 2021

Statin-induced, immune-mediated injury with simultaneous targeting of skeletal muscle, skin and liver.

Intern Emerg Med 2021 Feb 7. Epub 2021 Feb 7.

Dipartimento Di Medicina Sperimentale E Clinica, University of Florence, Largo Brambilla, 3, 50134, Florence, Italy.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11739-021-02652-9DOI Listing
February 2021

Metabolomic/lipidomic profiling of COVID-19 and individual response to tocilizumab.

PLoS Pathog 2021 02 1;17(2):e1009243. Epub 2021 Feb 1.

Magnetic Resonance Center (CERM), University of Florence, Sesto Fiorentino, Florence, Italy.

The current pandemic emergence of novel coronavirus disease (COVID-19) poses a relevant threat to global health. SARS-CoV-2 infection is characterized by a wide range of clinical manifestations, ranging from absence of symptoms to severe forms that need intensive care treatment. Here, plasma-EDTA samples of 30 patients compared with age- and sex-matched controls were analyzed via untargeted nuclear magnetic resonance (NMR)-based metabolomics and lipidomics. With the same approach, the effect of tocilizumab administration was evaluated in a subset of patients. Despite the heterogeneity of the clinical symptoms, COVID-19 patients are characterized by common plasma metabolomic and lipidomic signatures (91.7% and 87.5% accuracy, respectively, when compared to controls). Tocilizumab treatment resulted in at least partial reversion of the metabolic alterations due to SARS-CoV-2 infection. In conclusion, NMR-based metabolomic and lipidomic profiling provides novel insights into the pathophysiological mechanism of human response to SARS-CoV-2 infection and to monitor treatment outcomes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1371/journal.ppat.1009243DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7877736PMC
February 2021

Pulmonary vascular improvement in severe COVID-19 patients treated with tocilizumab.

Immunol Lett 2020 12 5;228:122-128. Epub 2020 Nov 5.

Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy; Immunology and Cell Therapy Unit, Careggi University Hospital, Florence, Italy. Electronic address:

As of October 2020 management of Coronavirus disease 2019 (COVID-19) is based on supportive care and off-label or compassionate-use therapies. On March 2020 tocilizumab - an anti-IL-6 receptor monoclonal antibody - was suggested as immunomodulatory treatment in severe COVID-19 because hyperinflammatory syndrome occurs in many patients similarly to the cytokine release syndrome that develops after CAR-T cell therapy. In our retrospective observational study, 20 severe COVID-19 patients requiring intensive care were treated with tocilizumab in addition to standard-of-care therapy (SOC) and compared with 13 COVID-19 patients receiving only SOC. Clinical respiratory status, inflammatory markers and vascular radiologic score improved after one week from tocilizumab administration. On the contrary, these parameters were stable or worsened in patients receiving only SOC. Despite major study limitations, improvement of alveolar-arterial oxygen gradient as well as vascular radiologic score after one week may account for improved pulmonary vascular perfusion and could explain the more rapid recovery of COVID-19 patients receiving tocilizumab compared to controls.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.imlet.2020.10.009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7644186PMC
December 2020

Cell-mediated and humoral adaptive immune responses to SARS-CoV-2 are lower in asymptomatic than symptomatic COVID-19 patients.

Eur J Immunol 2020 Dec 9;50(12):2013-2024. Epub 2020 Nov 9.

Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy.

The characterization of cell-mediated and humoral adaptive immune responses to SARS-CoV-2 is fundamental to understand COVID-19 progression and the development of immunological memory to the virus. In this study, we detected T-cells reactive to SARS-CoV-2 proteins M, S, and N, as well as serum virus-specific IgM, IgA, IgG, in nearly all SARS-CoV-2 infected individuals, but not in healthy donors. Virus-reactive T cells exhibited signs of in vivo activation, as suggested by the surface expression of immune-checkpoint molecules PD1 and TIGIT. Of note, we detected antigen-specific adaptive immune response both in asymptomatic and symptomatic SARS-CoV-2 infected subjects. More importantly, symptomatic patients displayed a significantly higher magnitude of both cell-mediated and humoral adaptive immune response to the virus, as compared to asymptomatic individuals. These findings suggest that an uncontrolled adaptive immune response contribute to the development of the life-threatening inflammatory phase of the disease. Finally, this study might open the way to develop effective vaccination strategies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/eji.202048915DOI Listing
December 2020

Quantitative and qualitative alterations of circulating myeloid cells and plasmacytoid DC in SARS-CoV-2 infection.

Immunology 2020 12 6;161(4):345-353. Epub 2020 Oct 6.

Flow Cytometry Diagnostic Center and Immunotherapy (CDCI), AOU Careggi, Florence, Italy.

SARS-CoV-2 is responsible for a new infectious disease (COVID-19) in which individuals can either remain asymptomatic or progress from mild to severe clinical conditions including acute respiratory distress syndrome and multiple organ failure. The immune mechanisms that potentially orchestrate the pathology in SARS-CoV-2 infection are complex and only partially understood. There is still paucity of data on the features of myeloid cells involved in this viral infection. For this reason, we investigated the different activation status profiles and the subset distribution of myeloid cells and their correlation with disease progression in 40 COVID-19 patients at different stages of disease. COVID-19 patients showed a decrease in the absolute number of plasmacytoid and myeloid dendritic cells, different subset distribution of monocytes and different activation patterns of both monocytes and neutrophils, coupled to a significant reduction of HLA-DR monocyte levels. We found that some of these alterations are typical of all COVID-19 patients, while some others vary at different stages of the disease and correlate with biochemical parameters of inflammation. Collectively, these data suggest that not only the lymphoid, but also the myeloid compartment, is severely affected by SARS-CoV-2 infection.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/imm.13254DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7692244PMC
December 2020

Plasticity and regulatory mechanisms of human ILC2 functions.

Immunol Lett 2020 11 18;227:109-116. Epub 2020 Aug 18.

Department of Experimental and Clinical Medicine and DENOTHE Center, University of Florence, Florence, 50134, Italy.

Human group 2 innate lymphoid cells (ILC2) represent the innate counterpart of Th2 cells and cooperate with them in helminths protection and in the pathogenesis of allergic diseases. Some reports described ILC2 plasticity and few studies investigated the cellular and molecular mechanisms regulating human ILC2 functions. The aim of this study is to define how immune deviation and immune regulation control human ILC2-mediated immune response. Human circulating ILC2 were expanded in vitro and then cultured in presence of IL-12 or IL-1β plus IL-23 or co-coltured in presence of circulating CD4+CD25highFoxp3+Treg. IL-12 induces IFN-γ production and upregulation of T-bet mRNA level on human circulating ILC2 whereas IL-1β and IL-23 mediate IL-22 production and upregulation of RORC mRNA level. In all these conditions, GATA-3 mRNA level is not reduced and the typical type 2 cytokines are only partially reduced. Moreover, "modulated" ILC2 have reduced ability to induce IgE producing by B cells. ILC2 proliferation, cytokines production and CD154 expression were inhibited by CD4+CD25highFoxp3+ Treg cells. TGF-β reduced CD154 expression on ILC2 stimulated with IL-25/IL-33. This study defines possible cellular and molecular mechanisms responsible for modulation and inhibition of human ILC2 activity. These results may be useful in the development of strategies aimed to dampen ILC2 function in type-2 mediated diseases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.imlet.2020.08.004DOI Listing
November 2020

Th17 lymphocyte-dependent degradation of joint cartilage by synovial fibroblasts in a humanized mouse model of arthritis and reversal by secukinumab.

Eur J Immunol 2021 01 9;51(1):220-230. Epub 2020 Aug 9.

Department of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Florence, Florence, Italy.

How T-helper (Th) lymphocyte subpopulations identified in synovial fluid from patients with juvenile idiopathic arthritis (JIA) (Th17, classic Th1, or nonclassic Th1) drive joint damage is of great interest for the possible use of biological drugs that inhibit the specific cytokines. Our objective was to clarify the role of such Th subpopulations in the pathogenesis of articular cartilage destruction by synovial fibroblasts (SFbs), and the effect of Th17 blockage in an animal model. SFbs were isolated from healthy subjects and patients with JIA, and peripheral blood Th lymphocytes subsets were obtained from healthy subjects. Fragments of human cartilage from healthy subjects in a collagen matrix containing JIA or normal SFbs grafted underskin in SCID mice were used to measure cartilage degradation under the effects of Th supernatants. JIA SFbs overexpress MMP9 and MMP2 and Th17 induce both MMPs in normal SFbs, while nonclassic Th1 upregulate urokinase plasminogen activator (uPA) activity. In vitro invasive phenotype of normal SFbs is stimulated with conditioned medium of Th17 and nonclassic-Th1. In the in vivo "inverse wrap" model, normal SFbs stimulated with supernatants of Th17-lymphocytes and nonclassic Th1 produced a cartilage invasion and degradation similar to JIA SFbs. Secukinumab inhibits the cartilage damage triggered by factors produced by Th17.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/eji.202048773DOI Listing
January 2021

Prompt Predicting of Early Clinical Deterioration of Moderate-to-Severe COVID-19 Patients: Usefulness of a Combined Score Using IL-6 in a Preliminary Study.

J Allergy Clin Immunol Pract 2020 Sep 19;8(8):2575-2581.e2. Epub 2020 Jun 19.

Immunoallergology Unit, Careggi University Hospital, Florence, Italy. Electronic address:

Background: The early identification of patients at risk of clinical deterioration is of interest considering the timeline of COVID-19 after the onset of symptoms.

Objective: The aim of our study was to evaluate the usefulness of testing serum IL-6 and other serological and clinical biomarkers, to predict a short-term negative clinical course of patients with noncritical COVID-19.

Methods: A total of 208 patients with noncritical COVID-19 pneumonia at admission were consecutively enrolled. Clinical and laboratory findings obtained on admission were analyzed by using survival analysis and stepwise logistic regression for variable selection. Three-day worsening as outcome in a logistic model to generate a prognostic score was used.

Results: Clinical worsening occurred in 63 patients (16 = died; 39 = transferred to intensive care unit; 8 worsening of respiratory failure). Forty-five of them worsened within 3 days after admission. The risk of clinical worsening was progressively enhanced along with increasing quartiles of IL-6 levels. Multivariate analysis showed that IL-6 (P = .005), C-reactive protein (CRP) (P = .003), and SaO/FiO (P = .014) were the best predictors for clinical deterioration in the first 3 days after admission. The combined score yielded an area under the curve = 0.88 (95% confidence interval: 0.83-0.93). A nomogram predicting the probability of 3-day worsening was generated. The score also showed good performance for 7-day and 14- or 21-day worsening and in predicting death occurring during all the follow-up.

Conclusions: Combining IL-6, CRP, and SaO/FiO in a score may help clinicians to identify on admission those patients with COVID-19 who are at high risk for a further 3-day clinical deterioration.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jaip.2020.06.013DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7303032PMC
September 2020

Impaired immune cell cytotoxicity in severe COVID-19 is IL-6 dependent.

J Clin Invest 2020 09;130(9):4694-4703

Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy.

BACKGROUNDCoronavirus disease 19 (COVID-19) is an emerging infectious disease caused by SARS-CoV-2. Antiviral immune response is crucial to achieve pathogen clearance; however, in some patients an excessive and aberrant host immune response can lead to an acute respiratory distress syndrome. The comprehension of the mechanisms that regulate pathogen elimination, immunity, and pathology is essential to better characterize disease progression and widen the spectrum of therapeutic options.METHODSWe performed a flow cytometric characterization of immune cell subsets from 30 patients with COVID-19 and correlated these data with clinical outcomes.RESULTSPatients with COVID-19 showed decreased numbers of circulating T, B, and NK cells and exhibited a skewing of CD8+ T cells toward a terminally differentiated/senescent phenotype. In agreement, CD4+ T and CD8+ T, but also NK cells, displayed reduced antiviral cytokine production capability. Moreover, a reduced cytotoxic potential was identified in patients with COVID-19, particularly in those who required intensive care. The latter group of patients also showed increased serum IL-6 levels that inversely correlated to the frequency of granzyme A-expressing NK cells. Off-label treatment with tocilizumab restored the cytotoxic potential of NK cells.CONCLUSIONThe association between IL-6 serum levels and the impairment of cytotoxic activity suggests the possibility that targeting this cytokine may restore antiviral mechanisms.FUNDINGThis study was supported by funds from the Department of Experimental and Clinical Medicine of University of Florence (the ex-60% fund and the "Excellence Departments 2018-2022 Project") derived from Ministero dell'Istruzione, dell'Università e della Ricerca (Italy).
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1172/JCI138554DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7456250PMC
September 2020

Human T cells interacting with HNSCC-derived mesenchymal stromal cells acquire tissue-resident memory like properties.

Eur J Immunol 2020 10 2;50(10):1571-1579. Epub 2020 Jun 2.

Department of Experimental and Clinical Medicine, University of Florence, Firenze, Italy.

Tissue-resident memory (Trm) cells are specialized components of both CD4+ and CD8+ T cell subsets that persist in peripheral nonlymphoid tissues following infections and provide fast response in case of a secondary invasion by the same pathogen. Trm cells express the surface markers CD69, CD103, and the immune checkpoint molecule PD-1. Trm cells develop not only in the context of infections but also in tumors, where they can provide a line of defense as suggested by the positive correlation between the frequency of tumor-infiltrating Trm cells and patients' survival. Trm cells persistence in peripheral tissues depends on their adaptation to the local microenvironment and the presence of survival factors, mainly IL-7, IL-15, and Notch ligands. However, the cell sources of these factors are largely unknown, especially in the context of tumors. Here, we show that head-neck squamous cell carcinoma (HNSCC) is enriched in CD4+ and CD8+ T cells with a Trm phenotype. Moreover, we show that mesenchymal stromal cells that accumulate in HNSCC are a source of survival factors and allow proper expression of Trm-typical markers in a VCAM1-dependent manner.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/eji.202048544DOI Listing
October 2020

Immunological insights on influenza infection and vaccination during immune checkpoint blockade in cancer patients.

Immunotherapy 2020 02 12;12(2):105-110. Epub 2020 Feb 12.

Department of Experimental & Clinical Medicine, University of Florence, Florence, Italy.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2217/imt-2019-0200DOI Listing
February 2020

Guidelines for the use of flow cytometry and cell sorting in immunological studies (second edition).

Eur J Immunol 2019 Oct;49(10):1457-1973

Flow Cytometry Laboratory, Institute of Molecular Toxicology and Pharmacology, Helmholtz Zentrum München, German Research Center for Environmental Health, München, Germany.

These guidelines are a consensus work of a considerable number of members of the immunology and flow cytometry community. They provide the theory and key practical aspects of flow cytometry enabling immunologists to avoid the common errors that often undermine immunological data. Notably, there are comprehensive sections of all major immune cell types with helpful Tables detailing phenotypes in murine and human cells. The latest flow cytometry techniques and applications are also described, featuring examples of the data that can be generated and, importantly, how the data can be analysed. Furthermore, there are sections detailing tips, tricks and pitfalls to avoid, all written and peer-reviewed by leading experts in the field, making this an essential research companion.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/eji.201970107DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7350392PMC
October 2019

Biological and clinical significance of T helper 17 cell plasticity.

Immunology 2019 12 14;158(4):287-295. Epub 2019 Oct 14.

Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy.

Mature T helper (Th) effector cells originate following antigen recognition by naive T precursors. The maturation process is accompanied by the acquisition of specific effector functions that distinguish at least three different T helper subsets: Th1, Th2 and Th17. In general, maturation of somatic cells is accompanied by terminal differentiation. However, accumulating evidence shows that effector T cells retain a certain degree of plasticity. This is especially true for Th17 cells, which have been shown to converge towards other phenotypes in response to specific microenvironmental pressure. In this review we will discuss the experimental evidence that supports the hypothesis of Th17 plasticity, with particular emphasis on the generation of Th17-derived 'non-classic' Th1 cells, and the molecular networks that control it. Moreover, we will consider why Th17 plasticity is important for host protection, but also why it can have pathogenic functions during chronic inflammation. Regarding the last point, we will discuss a possible role for biological drugs in the control of Th17 plasticity and disease course.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/imm.13124DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6856928PMC
December 2019

Biologicals targeting type 2 immunity: Lessons learned from asthma, chronic urticaria and atopic dermatitis.

Eur J Immunol 2019 09 12;49(9):1334-1343. Epub 2019 Aug 12.

Department of Experimental and Clinical Medicine and DENOTHE Center, University of Florence, Florence, Italy.

During the last decades, progression of research has led to great achievements for treatment and therapy of several disabling disorders, particularly in the field of chronic inflammatory diseases. The increased knowledge of the molecular mechanisms operating in such diseases has represented the first step in this process, and the discovery of molecules able to interfere with the natural history of the diseases, has been the second. This review is focused on the effects of biologics on type 2 diseases such as asthma, chronic urticaria and atopic dermatitis, both biologics just approved for clinical application and also those that are currently undergoing clinical trials. We will also discuss aspects and emphasize clinical trials and recently published studies, as well as research that is currently in the progress, which will be highly relevant for basic immunologists. Likewise, we will cover aspects that are pertinent for clinical immunologists and highlight translational studies that are evaluating novel biologicals in animal models.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/eji.201948156DOI Listing
September 2019

Th17 and Th1 Lymphocytes in Oligoarticular Juvenile Idiopathic Arthritis.

Front Immunol 2019 14;10:450. Epub 2019 Mar 14.

Department of Experimental and Clinical Medicine and DENOTHE Center, University of Florence, Florence, Italy.

In the last years much attention has focused on the Th17 and Th1 phenotypes and on their pathogenic role in juvenile idiopathic arthritis, investigating how the cytokines produced by T helper cells act on resident cells on the synovia and which signal transduction pathways regulate Th17 cells proliferation and plasticity. In this context, an important milestone was represented by the identification of the non-classic Th1 phenotype, developed from the shift of Th17 cells. The cytokine TNF-α, beyond its well-known proinflammatory activity is involved in this process and this is one of the reasons why the TNF-α inhibitors are widely used in the treatment of juvenile idiopathic arthritis patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fimmu.2019.00450DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6428030PMC
June 2020

Omalizumab dampens type 2 inflammation in a group of long-term treated asthma patients and detaches IgE from FcεRI.

Eur J Immunol 2018 12 9;48(12):2005-2014. Epub 2018 Oct 9.

Department of Experimental and Clinical Medicine and DENOTHE Center, University of Florence, Florence, Italy.

Even if omalizumab is broadly used in the treatment of severe, allergic asthma, the immunological effects in long-term treated patients have not been fully elucidated. To this aim, a cohort of 15 allergic asthmatic patients treated with omalizumab for at least three years was compared with 12 allergic asthma patients treated with standard therapy. Omalizumab treated asthmatic patients showed lower frequencies of circulating plasmacytoid DCs, and lower CD154 expression on CD4 T-helper cells than the control group. Moreover, basophils and DCs from omalizumab-treated patients had lower surface expression of IgE compared to the control group. In a longitudinal evaluation of two patients that started omalizumab treatment, we show that FcεRI free of IgE were evident on basophils just after four weeks of drug administration. Finally, in vitro experiments with basophils obtained from healthy donors confirm that omalizumab is able to detach IgE from high affinity IgE receptors. Collectively these data indicate that long-term omalizumab treatment dampens type 2 inflammation acting on different cell types that play a pivotal role in the pathogenesis of allergic asthma. Moreover, we have identified a further mechanism of action of omalizumab, such as the ability to detach IgE from its receptor.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/eji.201847668DOI Listing
December 2018

Eomes controls the development of Th17-derived (non-classic) Th1 cells during chronic inflammation.

Eur J Immunol 2019 01 22;49(1):79-95. Epub 2018 Nov 22.

Department of Experimental and Clinical Medicine and DENOTHE Center, University of Florence, Firenze, Italy.

It is well accepted that Th17 cells are a highly plastic cell subset that can be easily directed toward the Th1 phenotype in vitro and also in vivo during inflammation. However, there is an ongoing debate regarding the reverse plasticity (conversion from Th1 to Th17). We show here that ectopic ROR-γt expression can restore or initiate IL-17 expression by non-classic or classic Th1 cells, respectively, while common pro-Th17 cytokine cocktails are ineffective. This stability of the Th1 phenotype is at least partially due to the presence of a molecular machinery governed by the transcription factor Eomes, which promotes IFN-γ secretion while inhibiting the expression of ROR-γt and IL-17. By using a mouse model of T cell-dependent colitis we demonstrate that Eomes controls non-classic Th1 cell development also in vivo and promotes their pathogenic potential. Eomes expression associates to a highly inflammatory phenotype also in patients with juvenile idiopathic arthritis. Indeed, it favors the acquisition of a cytotoxic signature, and promotes the development of IFN-γ GM-CSF cells that have been described to be pathogenic in chronic inflammatory disorders.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/eji.201847677DOI Listing
January 2019

Efficacy and Safety of Mepolizumab (Anti-Interleukin-5) Treatment in Gleich's Syndrome.

Front Immunol 2018 29;9:1198. Epub 2018 May 29.

Department of Biomedicine, Immunoallergology Unit, AOU Careggi, Florence, Italy.

Gleich's syndrome (GS) is characterized by recurrent episodes of angioedema, increase in body weight, fever, hypereosinophilia, and elevated serum IgM. The exact etiology remains unclear. Currently, the only treatment strategy is the administration of high dose of steroids during the acute phases. We report the case of a 37-year-old man suffering from GS with recurrent episodes of angioedema, fever, hypereosinophilia [6,000/mm (45%)], and high eosinophil cationic protein (ECP) (>200 μg/l), treated with oral steroids during the acute phase (prednisone 50-75 mg/day), the dose of maintenance being 25 mg/day. No monoclonal components were identified, and genetic tests exclude mutations including Bcr/Abl, JAK2 V617F, c-KIT D816V, and FIP1L1-PDGFRA. Using Luminex technology, we observed higher serum levels of interleukin (IL)-5, CCL2, and CCL11 during the acute exacerbations in comparison with the clinical remission phases though CCL11 did not achieve statistical significance. The flow-cytometric analysis identified a CD3+ CD8- lymphocyte population with high frequency of IL-4-, IL-5-, and IL-13-producing cells. No clinical benefit was observed after therapeutic strategies with imatinib, interferon-α, cyclosporine-A, and azathioprine. Due to high IL-5 serum levels, an intravenous treatment with anti-IL-5 monoclonal antibody mepolizumab (750 mg every 4 weeks) was started. A reduction in the rate of exacerbation phases/year (10 ± 3 vs 2 ± 1;  < 0.005), in the eosinophils count both in percentage (28.8 ± 12.8 vs 9.8 ± 3.9;  < 0.001) and absolute value (2,737 ± 1,946 vs 782 ± 333;  < 0.001) were observed as well as the ECP serum levels (132.7 ± 62.7 vs 21 ± 14.2 μg/l;  < 0.05). The daily dose of prednisone was significantly reduced (25 vs 7.5 mg). Any adverse effects were recorded. To the best of our knowledge, this case is the first report of the disease successfully treated with mepolizumab, and it could represent a novel therapeutic strategy in GS.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fimmu.2018.01198DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5986952PMC
August 2019

Therapeutic Efficacy of Autologous Non-Mobilized Enriched Circulating Endothelial Progenitors in Patients With Critical Limb Ischemia - The SCELTA Trial.

Circ J 2018 05 23;82(6):1688-1698. Epub 2018 Mar 23.

San Giovanni di Dio Hospital.

Background: The therapeutic efficacy of bone marrow mononuclear cells (BM-MNC) autotransplantation in critical limb ischemia (CLI) has been reported. Variable proportions of circulating monocytes express low levels of CD34 (CD14CD34cells) and behave in vitro as endothelial progenitor cells (EPCs). The aim of the present randomized clinical trial was to compare the safety and therapeutic effects of enriched circulating EPCs (ECEPCs) with BM-MNC administration.Methods and Results:ECEPCs (obtained from non-mobilized peripheral blood by immunomagnetic selection of CD14and CD34cells) or BM-MNC were injected into the gastrocnemius of the affected limb in 23 and 17 patients, respectively. After a mean of 25.2±18.6-month follow-up, both groups showed significant and progressive improvement in muscle perfusion (primary endpoint), rest pain, consumption of analgesics, pain-free walking distance, wound healing, quality of life, ankle-brachial index, toe-brachial index, and transcutaneous PO. In ECEPC-treated patients, there was a positive correlation between injected CD14CD34cell counts and the increase in muscle perfusion. The safety profile was comparable between the ECEPC and BM-MNC treatment arms. In both groups, the number of deaths and major amputations was lower compared with eligible untreated patients and historical reference patients.

Conclusions: This study supports previous trials showing the efficacy of BM-MNC autotransplantation in CLI patients and demonstrates comparable therapeutic efficacy between BM-MNC and EPEPCs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1253/circj.CJ-17-0720DOI Listing
May 2018

Role of Type 2 Innate Lymphoid Cells in Allergic Diseases.

Curr Allergy Asthma Rep 2017 Sep 11;17(10):66. Epub 2017 Sep 11.

Department of Experimental and Clinical Medicine and DENOTHE Center, University of Florence, 50134, Florence, Italy.

Purpose Of Review: The adaptive immune response orchestrated by type 2 T helper (Th2) lymphocytes, strictly cooperates with the innate response of group 2 innate lymphoid cells (ILC2), in the protection from helminths infection, as well as in the pathogenesis of allergic disease. The aim of this review is to explore the pathogenic role of ILC2 in different type 2-mediated disorders.

Recent Findings: Recent studies have shown that epithelial cell-derived cytokines and their responding cells, ILC2, play a pathogenic role in bronchial asthma, chronic rhinosinusitis, and atopic dermatitis. The growing evidences of the contribution of ILC2 in the induction and maintenance of allergic inflammation in such disease suggest the possibility to target them in therapy. Biological therapies blocking ILC2 activation or neutralizing their effector cytokines are currently under evaluation to be used in patients with type 2-dominated diseases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11882-017-0735-9DOI Listing
September 2017

Musculin inhibits human T-helper 17 cell response to interleukin 2 by controlling STAT5B activity.

Eur J Immunol 2017 09 6;47(9):1427-1442. Epub 2017 Jul 6.

Department of Experimental and Clinical Medicine and DENOTHE Center, University of Florence, Firenze, Italy.

We recently demonstrated that human T-helper (Th) 17 cells, unlike Th1 cells, do not proliferate in response to T-cell receptor stimulation, mainly because of their reduced capacity to produce and respond to IL-2. In this study, we show that their lower responsiveness to IL-2 is due to the selective expression of Musculin (MSC), a member of the basic helix-loop-helix transcription factors. We show that MSC expression in human Th17 cells is retinoic acid orphan receptor (ROR)γt-dependent, and allows the upregulation of PPP2R2B, a regulatory member of the protein phosphatase 2A (PP2A) enzyme. High PPP2R2B levels in human Th17 cells were responsible for the reduced STAT5B Ser-193 phosphorylation upon IL-2 signalling and, therefore, impaired STAT5B DNA binding and transcriptional activity on IL-2 target genes. PP2A, observed in Th17 cells, controls also STAT3, dephosphorylating Ser727, thus increasing its activity that plays a crucial role in Th17 development and/or maintenance. Thus, our findings identify an additional mechanism responsible for the limited expansion of human Th17 cells, and could provide a further explanation for the rarity of these cells in inflamed tissues.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/eji.201746996DOI Listing
September 2017

Chitinase 3-like-1 is produced by human Th17 cells and correlates with the level of inflammation in juvenile idiopathic arthritis patients.

Clin Mol Allergy 2016 8;14:16. Epub 2016 Nov 8.

Department of Experimental and Clinical Medicine and DENOTHE Center, University of Florence, 50134 Florence, Italy.

Background: CHI3L1 is a chitinase-like protein without enzymatic activity, produced by activated macrophages, chondrocytes, neutrophils. Recent studies on arthritis, asthma, and inflammatory bowel diseases suggest that chitinases are important in inflammatory processes and tissue remodeling, but their production by human T cells, has never been reported.

Methods: A microarray analysis of gene expression profile was performed on Th17 and classic Th1 cell clones and CHI3L1 was found among the up-regulated genes on Th17 cells. Different types of helper T cell clones (TCCs) were then evaluated by Real Time PCR (RT-PCR) for CHI3L1 mRNA expression; protein expression was investigated in cell lysates by western blotting and in cultures supernatants by ELISA. ELISA was also used to measure CHI3L1 in the serum and in the synovial fluid (SF) of juvenile idiopathic arthritis (JIA) patients.

Results: At mRNA level CHI3L1 was highly expressed by Th17, Th17/Th1, non classic Th1 and even in Th17/Th2 cell clones, whereas it was virtually absent in CD161- classic Th1 and Th2 TCCs. CHI3L1 was also detected in cell culture supernatants of Th17 and Th17-derived cells but not of classic Th1. Moreover CHI3L1 was higher in the SF than in serum of JIA patients, and it positively correlated with the frequency of Th17 and non-classic Th1 cells in SF. CHI3L1 in SF also positively correlated with the C reactive protein (CRP) serum levels, and with the levels of some proinflammatory cytokines, such as IL-6 and p40, which is the common subunit of IL12 and IL23.

Conclusions: Here we describe for the first time CHI3L1 production by T cells owing the Th17 family. Moreover the positive correlation found between the frequency of Th17 and Th17-derived cell subsets and CHI3L1 levels in SF of JIA patients, in agreement with the suggested role of these cells in inflammatory process, candidates CHI3L1 as a possible biological target in JIA treatment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12948-016-0053-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5100333PMC
November 2016

Immunosuppressive Activity of Abatacept on Circulating T Helper Lymphocytes from Juvenile Idiopathic Arthritis Patients.

Int Arch Allergy Immunol 2016 8;171(1):45-53. Epub 2016 Nov 8.

Department of Experimental and Clinical Medicine and DENOTHE Center, University of Florence, Florence, Italy.

Background: Abatacept is used in the treatment of juvenile idiopathic arthritis (JIA) patients, but the activity of the drug on T helper cell function is not yet fully known.

Methods: The ability of abatacept to affect cytokine production in vitro and the proliferative response to both recall antigens and polyclonal stimulation was firstly assessed in healthy donors. Then, 10 JIA patients who were due to start abatacept treatment were recruited and longitudinally evaluated during the first 90 days of therapy. Both their clinical response to the treatment and in vitro analysis aimed to assess the proliferative response to recall antigens and the proportions of circulating T helper subsets.

Results: Abatacept reduced the proliferative response to recall antigens and the production of proinflammatory cytokines such as IFN-γ and TNF-α in healthy donors in vitro. It was also efficient in improving symptoms and reducing parameters of inflammation in JIA patients. Abatacept reduced the proliferative response to recall antigens, and this effect was significant soon after drug infusion (2 days). Regarding the proportions of circulating CD4+ T lymphocytes, only a reduction in the frequencies of circulating Treg cells was observed.

Conclusions: Abatacept in vitro inhibits proliferation and cytokine production in healthy donors, and reduces parameters of inflammation in vivo in JIA patients. The reduction of the proliferative response to recall antigens induced by abatacept was evident only soon after drug administration, suggesting that its immunosuppressive activity is maintained only for a short time.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1159/000450948DOI Listing
February 2017

Human circulating group 2 innate lymphoid cells can express CD154 and promote IgE production.

J Allergy Clin Immunol 2017 Mar 27;139(3):964-976.e4. Epub 2016 Jul 27.

Department of Experimental and Clinical Medicine and DENOTHE Center, Florence, Italy; Regenerative Medicine Unit and Immunology and Cellular Therapy Unit of Azienda Ospedaliera Careggi, Florence, Italy. Electronic address:

Background: Protection against helminths consists of adaptive responses by T2 cells and innate responses by group 2 innate lymphoid cells (ILC2s), with these latter being well characterized in mice but less so in human subjects.

Objective: We sought to characterize human circulating ILC2s and compare their functional profile with that of autologous T2 cells.

Methods: Circulating ILC2s and T2 cells were isolated by means of fluorescence-activated cell sorting and magnetic cell sorting and expanded in vitro. ILC2s were then stimulated with phorbol 12-myristate 13-acetate plus ionomycin, IL-25 plus IL-33 (IL-25/IL-33), or a mixture of Toll-like receptor ligands to evaluate their ability to produce cytokines, express CD154, and induce IgE production by autologous B cells. Cytokines and transcription factor gene methylation were assessed.

Results: ILC2s expressed GATA-3, retinoic acid orphan receptor (RORC) 2, and RORα; were able to produce IL-5, IL-13, and IL-4; and, accordingly, were characterized by demethylation of IL4, IL13, IL5, GATA3, and RORC2, whereas the IFNG, IFNG promoter, and TBX21 regions of interest were methylated. ILC2s expressed TLR1, TLR4, and TLR6, and TLR stimulation induced IL-5 and IL-13 production. Moreover, ILC2s expressed CD154 in response to phorbol 12-myristate 13-acetate plus ionomycin, IL-25/IL-33, or a mixture of TLR ligands. Stimulated ILC2s also induced IgM, IgG, IgA, and IgE production by B cells. Finally, circulating ILC2s from atopic patients were not different in numbers and frequency but expressed higher IL-4 levels than those from nonatopic subjects.

Conclusion: This study provides the first evidence that human ILC2s can express CD154 and stimulate the production of IgE by B lymphocytes through IL-25/IL-33 stimulation or TLR triggering.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jaci.2016.06.032DOI Listing
March 2017

Human herpesviruses respiratory infections in patients with acute respiratory distress (ARDS).

Med Microbiol Immunol 2016 Aug 2;205(4):371-9. Epub 2016 May 2.

Intensive Care Unit and Regional ECMO Referral Center, Azienda Ospedaliero-Universitaria Careggi, Florence, Italy.

Acute respiratory distress syndrome (ARDS) is today a leading cause of hospitalization in intensive care unit (ICU). ARDS and pneumonia are closely related to critically ill patients; however, the etiologic agent is not always identified. The presence of human herpes simplex virus 1, human cytomegalovirus and Epstein-Barr virus in respiratory samples of critically ill patients is increasingly reported even without canonical immunosuppression. The main aim of this study was to better understand the significance of herpesviruses finding in lower respiratory tract of ARDS patients hospitalized in ICU. The presence of this group of herpesviruses, in addition to the research of influenza viruses and other common respiratory viruses, was investigated in respiratory samples from 54 patients hospitalized in ICU, without a known microbiological causative agent. Moreover, the immunophenotype of each patient was analyzed. Herpesviruses DNA presence in the lower respiratory tract seemed not attributable to an impaired immunophenotype, whereas a significant correlation was observed between herpesviruses positivity and influenza virus infection. A higher ICU mortality was significantly related to the presence of herpesvirus infection in the lower respiratory tract as well as to impaired immunophenotype, as patients with poor outcome showed severe lymphopenia, affecting in particular T (CD3+) cells, since the first days of ICU hospitalization. In conclusion, these results indicate that herpesviruses lower respiratory tract infection, which occurs more frequently following influenza virus infection, can be a negative prognostic marker. An independent risk factor for ICU patients with ARDS is an impaired immunophenotype.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00430-016-0456-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7086591PMC
August 2016

Th1-Induced CD106 Expression Mediates Leukocytes Adhesion on Synovial Fibroblasts from Juvenile Idiopathic Arthritis Patients.

PLoS One 2016 28;11(4):e0154422. Epub 2016 Apr 28.

Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy.

This study tested the hypothesis that subsets of human T helper cells can orchestrate leukocyte adhesion to synovial fibroblasts (SFbs), thus regulating the retention of leukocytes in the joints of juvenile idiopathic arthritis (JIA) patients. Several cell types, such as monocytes/macrophages, granulocytes, T and B lymphocytes, SFbs and osteoclasts participate in joint tissue damage JIA. Among T cells, an enrichment of classic and non-classic Th1 subsets, has been found in JIA synovial fluid (SF), compared to peripheral blood (PB). Moreover, it has been shown that IL-12 in the SF of inflamed joints mediates the shift of Th17 lymphocytes towards the non-classic Th1 subset. Culture supernatants of Th17, classic and non-classic Th1 clones, have been tested for their ability to stimulate proliferation, and to induce expression of adhesion molecules on SFbs, obtained from healthy donors. Culture supernatants of both classic and non-classic Th1, but not of Th17, clones, were able to induce CD106 (VCAM-1) up-regulation on SFbs. This effect, mediated by tumor necrosis factor (TNF)-α, was crucial for the adhesion of circulating leukocytes on SFbs. Finally, we found that SFbs derived from SF of JIA patients expressed higher levels of CD106 than those from healthy donors, resembling the phenotype of SFbs activated in vitro with Th1-clones supernatants. On the basis of these findings, we conclude that classic and non-classic Th1 cells induce CD106 expression on SFbs through TNF-α, an effect that could play a role in leukocytes retention in inflamed joints.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0154422PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4849574PMC
March 2017

Th17 regulating lower airway disease.

Curr Opin Allergy Clin Immunol 2016 Feb;16(1):1-6

aDepartment of Experimental and Clinical Medicine, University of Florence bImmunology and Cell Therapy Unit cRegenerative Therapy Unit, AOU Careggi Hospital, Florence, Italy.

Purpose Of Review: Th17 lymphocytes are now widely believed to be critical for the regulation of various chronic immune diseases, including asthma and chronic obstructive pulmonary disease. In this review, we discuss the current understanding of the role of Th17 cells in the pathogenesis of different asthma phenotypes and chronic obstructive pulmonary disease.

Recent Findings: It has been recently reported that Th17 cells and also a new population of Th17/Th2 cells accumulate in bronchoalveolar lavage fluid of asthmatic patients, and positively correlated with airway obstruction and steroid resistance. These patients often have steroid resistant severe asthma and a predominant bronchial neutrophilic inflammation.

Summary: Steroid resistant severe asthma with predominant bronchial neutrophilic inflammation could benefit from IL-17 targeted therapies. In this view, the definition of clinical phenotypes and inflammatory endotypes of asthma in each patient will be necessary for personalizing the therapeutic approach.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/ACI.0000000000000227DOI Listing
February 2016

MDA5-positive dermatomyositis: an uncommon entity in Europe with variable clinical presentations.

Clin Mol Allergy 2015 9;13:22. Epub 2015 Nov 9.

Unit of Internal Medicine, Department of Experimental and Clinical Medicine, University of Florence, Largo Brambilla 3, 50134 Florence, Italy.

Clinically amyopathic dermatomyositis (CADM), described almost 50 years ago, is defined on the basis of still not validated criteria and characterized by skin findings almost without muscle weakness. Autoantibodies directed against the cytosolic pathogen sensor MDA5 (CADM 140) can mark this subtype of dermatomyositis which has been reported to associate, in particular ethnic groups, with severe progressive interstitial lung disease, poor prognosis and an hyperferritinemic status resembling hemophagocytic-like syndromes. MDA5 may be relevant in that Interferon-signature claimed to characterize inflammatory myopathies and dermatomyosits itself, but its role is not clear. However, the titre of anti-MDA5 autoantibodies seems to correlate with the outcome. In Caucasian populations the association between anti-MDA5 positive CADM and rapidly progressive interstitial lung disease seems to be weaker, but the limited numbers of patients described so far could explain the lack of statistical significance. As a fact, European patients with circulating anti-MDA5 autoantibodies may be clinically inhomogeneous and exhibit different rates of severity. The two patients affected by anti-MDA5 positive dermatomyositis described hereafter provide a clear example of the extreme variability of the disease in terms of laboratory findings and clinical features.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12948-015-0031-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4637993PMC
November 2015