Immunology

Treatment of murine lupus with TIGIT-Ig Publication date: June 2019 Source: Clinical Immunology, Volume 203 Author(s): Shuowu Liu, Lizhu Sun, Chuqi Wang, Yingshu Cui, Yuee Ling, Tian Li, Fangxing Lin, Wenyan Fu, Min Ding, Shuyi Zhang, Changhai Lei, Shi Hu Abstract The TIGIT (T cell immunoreceptor with Ig and ITIM domains) protein is a co-inhibitory receptor that has been reported to suppress autoreactive T and B cells to trigger immunological tolerance. We generated a new recombinant protein by connecting the extracellular domain of murine TIGIT to the Fc region of the mouse immunoglobulin IgG2a. The fusion protein was then characterized. The results suggested that among mice with lupus that were treated with the TIGIT-Ig fusion protein, the onset of proteinuria was delayed, serum concentrations of autoantibodies, such as antinuclear antibodies, were reduced without a decrease in the total IgG concentrations, and the survival rate was significantly increased compared to those of the controls. In conclusion, TIGIT-Ig administration showed promising results for both the prevention and treatment of autoimmune diseases in mice. This indicates that treatment with recombinant human TIGIT-Ig shows promise as an effective way to treat human autoimmune diseases.

Diminished cytolytic activity of γδ T cells with reduced DNAM-1 expression in neuroblastoma patients Publication date: June 2019 Source: Clinical Immunology, Volume 203 Author(s): Xiaolin Wang, Wenjun Mou, Wei Han, Yue Xi, Xi Chen, Hui Zhang, Hong Qin, Huanmin Wang, Xiaoli Ma, Jingang Gui Abstract Neuroblastoma is one of the children's malignant tumors with poor prognosis, as well as high recurrence and metastasis rates after surgical removal and chemotherapy. γδ T-cell based immunotherapy receives increasing attention thanks to their strong cytolytic activity to tumor cells. Our previous data revealed a significant increase in circulating γδ T-cell frequency in NB patients. In the present study, we found that beside a reduction of IFN-γ in serum of NB patients, DNAM-1 expression decreased in both circulating and PAM-expanded NB γδ T cells. Upon PAM stimulation, NB γδ T cells showed a reduced level of cell proliferation. In addition, the cytolytic activity of NB γδ T cells to NB cell lines was proved to be attenuated in a co-culture system. The fact that DNAM-1 neutralizing antibody abolished the tumor cell killing accentuates the indispensable role of DNAM-1 molecule in γδ T-cell cytolytic function.

MCC950 blocks enhanced interleukin-1β production in patients with NLRP3 low penetrance variants Publication date: June 2019 Source: Clinical Immunology, Volume 203 Author(s): E. Schuh, C.J. Groß, D. Wagner, M. Schlüter, O. Groß, T. Kümpfel Abstract Objective To determine the role of the NLRP3 inflammasome by using the selective NLRP3 inhibitor MCC950 in patients with NLRP3 low penetrance variants and clinical symptoms suggestive for an autoinflammatory syndrome including central nervous system (CNS) involvement. Methods Nineteen symptomatic patients with low penetrance NLRP3 variants (Q703K n = 17, V198M n = 2) recruited between 2011 and 2017 were included in this monocentric study. A functional inflammasome activation assay was performed in patients in comparison to healthy controls (HC), including the determination of interleukin-1beta (IL-1β), interleukin-6 (IL-6) and tumor-necrosis factor alpha (TNF-α) secretion in the presence of the NLRP3 selective small-molecule inhibitor MCC950. Detailed clinical features were assessed and anti-IL-1 treatment response was determined. Results Peripheral blood mononuclear cells (PBMC) from patients with low penetrance NLRP3 variants displayed enhanced IL-1β levels following inflammasome activation compared to HC. Furthermore, IL-1β release was NLRP3-dependent as it was blocked by MCC950. The production of IL-6 and TNF-α was also increased in patients with low penetrance NLRP3 variants. Clinically, they presented with a heterogenous spectrum of neurological manifestations, while cranial nerve inflammation was the most common feature. Overall inflammasome activation did not correlate with disease severity. Eight of ten treated patients responded to anti IL-1 treatment, however a complete response was only documented in four patients. Conclusion PBMC of several patients with NLRP3 low penetrance variants and CNS manifestation showed increased NLRP3-specific IL-1β release upon stimulation and elevated NLRP3-independent IL-6 and TNF-α levels as those were not suppressed by MCC950. Our data suggest that beside the possible causal involvement of the NLRP3 inflammasome additional, yet unidentified genetic or environmental factors may contribute to the multi-organ inflammation in our patients and explain the partial response to IL-1 targeting therapies.

Pathogenic roles of anti-C1q antibodies in recurrent pregnancy loss Publication date: June 2019 Source: Clinical Immunology, Volume 203 Author(s): Kazumasa Ohmura, Kenji Oku, Tamao Kitaori, Olga Amengual, Ryo Hisada, Masatoshi Kanda, Yuka Shimizu, Yuichiro Fujieda, Masaru Kato, Toshiyuki Bohgaki, Tetsuya Horita, Shinsuke Yasuda, Mayumi Sugiura-Ogasawara, Tatsuya Atsumi Abstract Recurrent pregnancy loss (RPL) is often considered idiopathic, however excessive complement activation has been observed in pregnancy related manifestations. Anti-C1q antibodies (anti-C1q) are associated with the activation of complement pathway in lupus patients, while it remains unclear in RPL. Firstly, we showed that both the prevalence and titre of anti-C1q were significantly higher in unexplained RPL than in healthy parous individuals. Secondly, we established the murine model of anti-C1q induced pregnancy loss using a monoclonal anti-mouse C1q antibody, JL-1. In mice treated with JL-1, high ratio of pregnancy loss and fetal growth restriction were frequently observed and complement activation occurred. C5a receptor (C5aR) blockade cancelled these pathogenic changes in mice treated with JL-1. In conclusion, our study reveals an association between the prevalence of anti-C1q and RPL. Additionally, our murine model has indicated that anti-C1q can induce reproductive failure, which might be ameliorated by therapy targeting the C5-C5aR axis.

DNA damage accumulation, defective chromatin organization and deficient DNA repair capacity in patients with rheumatoid arthritis Publication date: June 2019 Source: Clinical Immunology, Volume 203 Author(s): Vassilis L. Souliotis, Nikolaos I. Vlachogiannis, Maria Pappa, Alexandra Argyriou, Petros P. Sfikakis Abstract We investigated the DNA damage response and repair network in 18 patients with active rheumatoid arthritis and tested the hypothesis that treatment influences this network. A 3-fold increase of endogenous DNA damage (single- and double-strand breaks) was detected in patient-derived peripheral blood mononuclear cells than controls (alkaline comet assay; mean ± SD Olive Tail Moment of 11.8 ± 7.3 versus 4.3 ± 2.2, p < .001). Patients exhibited significantly higher formation of DNA damage (oxidative stress and abasic sites), deficient global genome repair and more condensed chromatin structure than controls. Twelve weeks following treatment, chromatin structure loosened, global genome repair capacity was restored, oxidative stress and abasic sites decreased and levels of endogenous DNA damage reached control values in all 8 patients examined. We conclude that deregulated chromatin organization, deficient DNA repair capacity and augmented formation of DNA damage, which are reversible after treatment, contribute to the accumulation of endogenous DNA damage in rheumatoid arthritis.

Characteristics of regulatory T-cell populations before and after Ty21a typhoid vaccination in children and adults Publication date: June 2019 Source: Clinical Immunology, Volume 203 Author(s): Mark E. Rudolph, Monica A. McArthur, Laurence S. Magder, Robin S. Barnes, Wilbur H. Chen, Marcelo B. Sztein Abstract Typhoid fever, caused by the pathogen Salmonella enterica serovar Typhi (S. Typhi), is a serious global health concern. Challenge studies with wild type S. Typhi identified associations between gut-homing regulatory T cells (Treg) and development of typhoid disease. Whether oral live-attenuated Ty21a vaccination induces gut-homing Treg remains unclear. Here, we analyze pediatric and adult Treg pre- and post-Ty21a vaccination in an autologous S. Typhi-antigen presentation model to address this knowledge gap. We show that peripheral memory Treg populations change from childhood to adulthood, but not following Ty21a vaccination. Unsupervised dimensionality reduction with t-distributed stochastic neighbor embedding (tSNE) identifies homing, memory, and functional features which evidence age-associated maturation of multifunctional S. Typhi-responsive Treg, which were not impacted by Ty21a vaccination. These findings improve understanding of pediatric regulatory T cells, while identifying age-related differences in S. Typhi-responsive Treg, which may aid in the development of improved pediatric vaccination strategies against S. Typhi.

Autoimmune/inflammatory syndrome induced by adjuvants (ASIA) demonstrates distinct autoimmune and autoinflammatory disease associations according to the adjuvant subtype: Insights from an analysis of 500 cases Publication date: June 2019 Source: Clinical Immunology, Volume 203 Author(s): Abdulla Watad, Nicola Luigi Bragazzi, Dennis McGonagle, Mohammed Adawi, Charlie Bridgewood, Giovanni Damiani, Jaume Alijotas-Reig, Enrique Esteve-Valverde, Mariana Quaresma, Howard Amital, Yehuda Shoenfeld Abstract Background We investigated the pattern of reported immune diseases in the international ASIA syndrome registry. Methods Data from 500 subjects exposed to adjuvants from the ASIA syndrome international registry were analysed. Results The patient mean age was 43 ± 17 years and 89% were female. Within the reported immune diseases, 69% were well-defined immune diseases (autoimmune, autoinflammation, and mixed pattern diseases). Among the well-defined immune diseases following the exposure to adjuvants, polygenic autoimmune diseases were significantly higher than autoinflammatory disorders (92.7% vs 5.8%, respectively, p < 0.001). Polygenic autoimmune diseases such as connective tissue diseases were significantly linked to the exposure to HBV vaccine (OR 3.15 [95%CI 1.08–9.23], p = 0.036). Polygenic autoinflammatory diseases were significantly associated with the exposure to influenza vaccination (OR 10.98 [95%CI 3.81–31.67], p < 0.0001). Conclusions Immune conditions following vaccination are rare, and among these, polygenic autoimmune diseases represent the vast majority of the well-defined immune diseases reported under the umbrella ASIA syndrome. However, vaccines benefit outweighs their autoimmune side effects.

Evaluating laboratory criteria for combined immunodeficiency in adult patients diagnosed with common variable immunodeficiency Publication date: June 2019 Source: Clinical Immunology, Volume 203 Author(s): Caroline von Spee-Mayer, Verena Koemm, Claudia Wehr, Sigune Goldacker, Gerhard Kindle, Alla Bulashevska, Michele Proietti, Bodo Grimbacher, Stephan Ehl, Klaus Warnatz Abstract Some patients diagnosed with common variable immunodeficiency (CVID) actually suffer from combined immunodeficiency (CID) and therefore may require a different, CID-adapted treatment. Several CD4 T-cell-based criteria have been proposed in the past to identify patients with CID within the cohort of adult CVID patients. In this monocentric study, we used retrospective immunological and clinical data of 238 CVID patients to compare four different proposals of how to define CID among CVID patients. We demonstrate that none of the current definitions sufficiently separates CID from CVID patients and that the relative reduction of naïve CD4 T cells <10% has the highest sensitivity of all tested markers for patients with clinical complications often associated with CID. Thus, a very low percentage of naïve CD4 T cells in any adult CVID patient should raise suspicion, but is not sufficient to define CID among CVID patients.

Pathogenic NFKB2 variant in the ankyrin repeat domain (R635X) causes a variable antibody deficiency Publication date: June 2019 Source: Clinical Immunology, Volume 203 Author(s): Paul Tuijnenburg, Hana Lango Allen, Godelieve J. de Bree, Sinisa Savic, Machiel H. Jansen, Claire Stockdale, Ilenia Simeoni, Ineke J.M. ten Berge, Ester M.M. van Leeuwen, NIHR BioResource, James E. Thaventhiran, Taco W. Kuijpers Abstract Genetic studies are identifying an increasing number of monogenic causes of Common Variable Immunodeficiency (CVID). Pathogenic variants in the C-terminus of NFKB2 have been identified in the subset of CVID patients whose immunodeficiency is associated with ectodermal dysplasia and central adrenal insufficiency. We describe 2 unrelated CVID pedigrees with 4 cases of pathogenic stop gain variants (c.1903C > T) in the ankyrin repeat domain (ARD) of NF-κB2, leading to a premature truncation of the protein at p.Arg635Term (R635X). By immunophenotyping and functional ex vivo B- and T-cell experiments we characterized the variant by reduced class-switched memory B-cell counts and immature plasmablasts, unable to produce IgG and IgA. Features of a poor proliferative T-cell response and reduced expansion of CD4+CXCR5+ T cells was only observed in the two clinically affected index cases without any clear clinical correlate. In conclusion, pathogenic stop variants in the ARD of NFKB2 can cause 'infection-only' CVID with an abnormal B-cell phenotype and a variable clinical penetrance.

Identification of autoantibodies using human proteome microarrays in patients with IPEX syndrome Publication date: June 2019 Source: Clinical Immunology, Volume 203 Author(s): Akihiro Hoshino, Hirokazu Kanegane, Masanori Nishi, Ikuya Tsuge, Kiriko Tokuda, Ichiro Kobayashi, Kohsuke Imai, Tomohiro Morio, Masatoshi Takagi Abstract Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome is one of the inborn errors of immunity, characterized by impaired function of the regulatory T cells. Clinical manifestations of IPEX syndrome are characterized by various autoimmune diseases with autoantibodies. The comprehensive analysis for autoantibodies using human proteome microarrays in the four patients with IPEX syndrome was performed. The numbers of the highly expressed autoantibody showing relative log2 ratios greater than 1 were 1876, 513, 234 and 831 (mean: 864), respectively. Some novel autoantibodies which could explain the phenotypes of patients, adrenal dysfunction, muscular hypotonia, afibrinogenemia, enteropathy and pancytopenia were identified. Various kinds of autoantibodies targeting testis-specific antigens were also identified. Human proteome microarray is a powerful tool to understand the pathophysiology of IPEX syndrome. The larger cohort analysis using this method will provide further understanding of the impaired immune tolerance in humans.