Follicular helper T cells (TFH) represent a distinct subset of CD4(+) T cells specialized in providing help to B lymphocytes, which may play a central role in autoimmune diseases having a major B ...cell component such as systemic lupus erythematosus. Recently, TFH subsets that share common phenotypic and functional characteristics with TFH cells from germinal centers, have been described in the peripheral blood from healthy individuals. The aim of this study was to analyze the distribution of such populations in lupus patients. Circulating TFH cell subsets were defined by multicolor flow cytometry as TFH17 (CXCR3(-)CCR6(+)), TFH1 (CXCR3 (+) CCR6(-)) or TFH2 (CXCR3(-)CCR6(-)) cells among CXCR5 (+) CD45RA(-)CD4(+) T cells in the peripheral blood of 23 SLE patients and 23 sex and age-matched healthy controls. IL-21 receptor expression by B cells was analyzed by flow cytometry and the serum levels of IL-21 and Igs were determined by ELISA tests. We found that the TFH2 cell subset frequency is strongly and significantly increased in lupus patients with an active disease (SLEDAI score>8), while the TFH1 cell subset percentage is greatly decreased. The TFH2 and TFH1 cell subset frequency alteration is associated with the presence of high Ig levels and autoantibodies in patient's sera. Moreover, the TFH2 cell subset enhancement correlates with an increased frequency of double negative memory B cells (CD27(-)IgD(-)CD19(+) cells) expressing the IL-21R. Finally, we found that IgE levels in lupus patients' sera correlate with disease activity and seem to be associated with high TFH2 cell subset frequency. In conclusion, our study describes for the first time the distribution of circulating TFH cell subsets in lupus patients. Interestingly, we found an increased frequency of TFH2 cells, which correlates with disease activity. Our results suggest that this subset might play a key role in lupus pathogenesis.
Treatment for autoimmune diseases such as systemic lupus erythematosus (SLE), idiopathic inflammatory myositis, and systemic sclerosis often involves long-term immune suppression. Resetting aberrant ...autoimmunity in these diseases through deep depletion of B cells is a potential strategy for achieving sustained drug-free remission.
We evaluated 15 patients with severe SLE (8 patients), idiopathic inflammatory myositis (3 patients), or systemic sclerosis (4 patients) who received a single infusion of CD19 chimeric antigen receptor (CAR) T cells after preconditioning with fludarabine and cyclophosphamide. Efficacy up to 2 years after CAR T-cell infusion was assessed by means of Definition of Remission in SLE (DORIS) remission criteria, American College of Rheumatology-European League against Rheumatism (ACR-EULAR) major clinical response, and the score on the European Scleroderma Trials and Research Group (EUSTAR) activity index (with higher scores indicating greater disease activity), among others. Safety variables, including cytokine release syndrome and infections, were recorded.
The median follow-up was 15 months (range, 4 to 29). The mean (±SD) duration of B-cell aplasia was 112±47 days. All the patients with SLE had DORIS remission, all the patients with idiopathic inflammatory myositis had an ACR-EULAR major clinical response, and all the patients with systemic sclerosis had a decrease in the score on the EUSTAR activity index. Immunosuppressive therapy was completely stopped in all the patients. Grade 1 cytokine release syndrome occurred in 10 patients. One patient each had grade 2 cytokine release syndrome, grade 1 immune effector cell-associated neurotoxicity syndrome, and pneumonia that resulted in hospitalization.
In this case series, CD19 CAR T-cell transfer appeared to be feasible, safe, and efficacious in three different autoimmune diseases, providing rationale for further controlled clinical trials. (Funded by Deutsche Forschungsgemeinschaft and others.).
Autosomal dominant gain-of-function mutations in human stimulator of interferon genes (STING) lead to a severe autoinflammatory disease called STING-associated vasculopathy with onset in infancy that ...is associated with enhanced expression of interferon-stimulated gene transcripts.
The goal of this study was to analyze the phenotype of a new mouse model of STING hyperactivation and the role of type I interferons in this system.
We generated a knock-in model carrying an amino acid substitution (V154M) in mouse STING, corresponding to a recurrent mutation seen in human patients with STING-associated vasculopathy with onset in infancy. Hematopoietic development and tissue histology were analyzed. Lymphocyte activation and proliferation were assessed in vitro. STING V154M/wild-type (WT) mice were crossed to IFN-α/β receptor (IFNAR) knockout mice to evaluate the type I interferon dependence of the mutant Sting phenotype recorded.
In STING V154M/WT mice we detected variable expression of inflammatory infiltrates in the lungs and kidneys. These mice showed a marked decrease in survival and developed a severe combined immunodeficiency disease (SCID) affecting B, T, and natural killer cells, with an almost complete lack of antibodies and a significant expansion of monocytes and granulocytes. The blockade in B- and T-cell development was present from early immature stages in bone marrow and thymus. In addition, in vitro experiments revealed an intrinsic proliferative defect of mature T cells. Although the V154M/WT mutant demonstrated increased expression of interferon-stimulated genes, the SCID phenotype was not reversed in STING V154M/WT IFNAR knockout mice. However, the antiproliferative defect in T cells was rescued partially by IFNAR deficiency.
STING gain-of-function mice developed an interferon-independent SCID phenotype with a T-cell, B-cell, and natural killer cell developmental defect and hypogammaglobulinemia that is associated with signs of inflammation in lungs and kidneys. Only the intrinsic proliferative defect of T cells was partially interferon dependent.
Drug repurposing is used to propose new therapeutic perspectives. Here, we introduce “Drug Upgrade”, that is, characterizing the mode of action of an old drug to generate new chemical entities and ...new therapeutics. We proposed a novel methodology covering target identification to pharmacology validation. As an old drug, we chose hydroxychloroquine (HCQ) for its well‐documented clinical efficacy in lupus and its side effect, retinal toxicity. Using the Nematic Protein Organization Technique (NPOT®) followed by liquid chromatography‐tandem mass spectrometry analyses, we identified myeloperoxidase (MPO) and alpha‐crystallin β chain (CRYAB) as primary and secondary targets to HCQ from lupus patients' peripheral blood mononuclear cells (PBMCs) and isolated human retinas. Surface plasmon resonance (SPR) and enzymatic assays confirmed the interaction of HCQ with MPO and CRYAB. We synthesized INS‐072 a novel analog of HCQ that increased affinity for MPO and decreased binding to CRYAB compared to HCQ. INS‐072 delayed cutaneous eruption significantly compared to HCQ in the murine MRL/lpr model of spontaneous lupus and prevents immune complex vasculitis in mice. In addition, long‐term HCQ treatment caused retinal toxicity in mice, unlike INS‐072. Our study illustrates a method of drug development, where new applications or improvements can be explored by fully characterizing the drug's mode of action.
ZAP70 has a prognostic value in chronic lymphocytic leukemia (CLL), through altered B‐cell receptor signaling, which is important in CLL pathogenesis. A good correlation between ZAP70 expression in ...CLL cells and the occurrence of autoimmune phenomena has been reported. Yet, the great majority of CLL‐associated autoimmune cytopenia is due to polyclonal immunoglobulin (Ig) G synthesized by nonmalignant B cells, and this phenomenon is poorly understood. Here, we show, using flow cytometry, that a substantial percentage of CD5‐ nonmalignant B cells from CLL patients expresses ZAP70 compared with CD5‐ B cells from healthy subjects. This ZAP70 expression in normal B cells from CLL patients was also evidenced by the detection of ZAP70 mRNA at single‐cell level with polyclonal Ig heavy‐ and light‐chain gene transcripts. ZAP70+ normal B cells belong to various B‐cell subsets and their presence in the naïve B‐cell subset suggests that ZAP70 expression may occur during early B‐cell development in CLL patients and potentially before malignant transformation. The presence of ZAP70+ normal B cells is associated with autoimmune cytopenia in CLL patients in our cohort of patients, and recombinant antibodies produced from these ZAP70+ nonmalignant B cells were frequently autoreactive including anti‐platelet reactivity. These results provide a better understanding of the implication of ZAP70 in CLL leukemogenesis and the mechanisms of autoimmune complications of CLL.
Non‐malignant CD5‐ B cells from CLL patients express ZAP70. These ZAP70+CD5‐ B cells may be involved in the development of autoimmunity in CLL patients.
To describe changes in the 2001–2014 mortality of 6 autoimmune systemic diseases (AISDs), namely Systemic Lupus Erythematosus (SLE), Systemic Sclerosis (SSc), Idiopathic Inflammatory Myopathies ...(IIM), Sjögren's Syndrome (SS), Mixed Connective Tissue Disease (MCTD) and ANCA-associated vasculitis (AAV) at the country-, continent-, and world-levels.
Mortality data were retrieved from the World Health Organization (WHO) mortality database for each disease, based on ICD-10 codes. We computed age-standardized mortality rate (ASMR) as the estimated number of deaths per million inhabitants and its 95% confidence interval (95%CI). The association between gender, geographical areas and disease-specific mortality was analyzed using multivariate Poisson regression. The 2001–2014 temporal trends were analyzed using Jointpoint software.
In 2014, the worldwide ASMR for SLE was 2.68 (95%CI: 2.62–2.75) deaths/millions inhabitants, 1.46 (1.42–1.51) for SSc, 0.47 (0.44–0.49) for IIM, 0.17 (0.15–0.18) for SS, 0.11 (0.10–0.13) for MCTD and 0.53 (0.50–0.56) for AAV, with ASMRs generally lower in Europe than in North America, Latin America and Asia. Between 2001 and 2014, the worldwide ASMR decreased significantly for SSc (−0.71%/year), IIM (−1.65%/year) and AAV (−1.01%/year; p < .001 for all) and increased for SS (+1.53%/year, p = .01). The worldwide ASMR of SLE decreased significantly between 2001 and 2003 (−6.37%, p < .05) before increasing slightly between 2004 and 2014 (+0.58%, p < .01).
We observed a strong heterogeneity of standardized mortality rates across all countries analyzed for 6 autoimmune diseases. Those results further highlight the impact of world-wide inequities and major gaps in access to care and strategies for diagnosis and management of rare diseases, a crucial finding for world-wide physicians, patient associations and policy makers.
•The age-standardized mortality rate (ASMR) of 6 auto-immune diseases was computed using the WHO mortality database.•The ASMR were generally lower in Europe than in North America, Latin America and Asia.•Between 2001 and 2014, there was a significant worldwide decrease of the ASMR of SSc, IIM & AAVs while it increased for SLE and Sjögren's
Objective
Silica is an environmental substance strongly linked with autoimmunity. The aim of this study was to assess the prevalence of antineutrophil cytoplasmic antibody (ANCA)–associated ...vasculitis (AAV), including granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and renal limited vasculitis, in a northeastern region of France and to evaluate whether there was a geospatial association between the localization of quarries in the region and the prevalence of these AAVs.
Methods
Potential AAV patients were identified using 3 sources: hospital records, immunology laboratories, and the French National Health Insurance System. Patients who resided in the Alsace region of France as of January 1, 2016 and who fulfilled the American College of Rheumatology criteria for GPA or the 2012 Chapel Hill Consensus Conference definitions for GPA or MPA were included. Incomplete case ascertainment was corrected using a capture–recapture analysis. The spatial association between the number of cases and the presence of quarries in each administrative entity was assessed using regression analyses weighted for geographic region.
Results
Among 910 potential AAV patients, we identified 185 patients fulfilling inclusion criteria: 120 patients with GPA, 35 patients with MPA, and 30 patients with renal limited vasculitis. The number of cases missed by any source as estimated by capture–recapture analysis was 6.4 (95% confidence interval 95% CI 3.6–11.5). Accordingly, the estimated prevalence in Alsace in 2016 was 65.5 GPA cases per million inhabitants (95% CI 47.3–93.0), 19.1 MPA cases per million inhabitants (95% CI 11.3–34.3), and 16.8 renal limited vasculitis cases per million inhabitants (95% CI 8.7–35.2). The risk of AAV was significantly increased in communities with quarries (odds ratio 2.51 95% CI 1.66–3.80), and geographic‐weighted regression analyses revealed a significant spatial association between the proximity to quarries and the number of GPA cases (P = 0.039). In analyses stratifying the AAV patients by ANCA serotype, a significant association between the presence of quarries and positivity for both proteinase 3 ANCAs (P = 0.04) and myeloperoxidase ANCAs (P = 0.03) was observed.
Conclusion
In a region with a high density of quarries, the spatial association between the presence of and proximity to quarries and the prevalence of AAVs supports the idea that silica may have a role as a specific environmental factor in this disease.
As the world is severely affected by COVID-19 pandemic, the use of chloroquine and hydroxychloroquine in prevention or for the treatment of patients is allowed in multiple countries but remained at ...the center of much controversy in recent days. This review describes the properties of chloroquine and hydroxychloroquine, and highlights not only their anti-viral effects but also their important immune-modulatory properties and their well-known use in autoimmune diseases, including systemic lupus and arthritis. Chloroquine appears to inhibit
SARS virus' replication and to interfere with SARS-CoV2 receptor (ACE2). Chloroquine and hydroxychloroquine impede lysosomal activity and autophagy, leading to a decrease of antigen processing and presentation. They are also known to interfere with endosomal Toll-like receptors signaling and cytosolic sensors of nucleic acids, which result in a decreased cellular activation and thereby a lower type I interferons and inflammatory cytokine secretion. Given the antiviral and anti-inflammatory properties of chloroquine and hydroxychloroquine, there is a rational to use them against SARS-CoV2 infection. However, the anti-interferon properties of these molecules might be detrimental, and impaired host immune responses against the virus. This duality could explain the discrepancy with the recently published studies on CQ/HCQ treatment efficacy in COVID-19 patients. Moreover, although these treatments could be an interesting potential strategy to limit progression toward uncontrolled inflammation, they do not appear
sufficiently potent to control the whole inflammatory process in COVID-19, and more targeted and/or potent therapies should be required at least in add-on.
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