Hashimoto's thyroiditis is now considered the most prevalent autoimmune disease, as well as the most common endocrine disorder. It was initially described in 1912, but only rarely reported until the ...early 1950s. To celebrate this centennial, we reviewed the surgical pathology archives of the Johns Hopkins hospital for cases of Hashimoto's thyroiditis, spanning the period from May 1889 to October 2012. Approximately 15,000 thyroidectomies were performed at this hospital over 124 years. The first surgical case was reported in 1942, 30 years after the original description. Then, 867 cases of Hashimoto's thyroiditis were seen from 1942 to 2012, representing 6% of all thyroidectomies. Hashimoto's thyroiditis was the sole pathological finding in 462 cases; it accompanied other thyroid pathologies in the remaining 405 cases. The most commonly associated pathology was papillary thyroid cancer, an association that increased significantly during the last two decades. The most common indication for thyroidectomy was a thyroid nodule that was cytologically suspicious for malignancy. Hashimoto's thyroiditis remains a widespread, intriguing, and multifaceted disease of unknown etiology one century after its description. Advances in the understanding of its pathogenesis and preoperative diagnosis will improve recognition and treatment of this disorder, and may one day lead to its prevention.
The regulatory properties of B cells have been studied in autoimmune diseases; however, their role in allergic diseases is poorly understood. We demonstrate that Semaphorin 4C (Sema4C), an axonal ...guidance molecule, plays a crucial role in B cell regulatory function. Mice deficient in Sema4C exhibited increased airway inflammation after allergen exposure, with massive eosinophilic lung infiltrates and increased Th2 cytokines. This phenotype was reproduced by mixed bone marrow chimeric mice with Sema4C deficient only in B cells, indicating that B lymphocytes were the key cells affected by the absence of Sema4C expression in allergic inflammation. We determined that Sema4C-deficient CD19
CD138
cells exhibited decreased IL-10 and increased IL-4 expression in vivo and in vitro. Adoptive transfer of Sema4c
CD19
CD138
cells induced marked pulmonary inflammation, eosinophilia, and increased bronchoalveolar lavage fluid IL-4 and IL-5, whereas adoptive transfer of wild-type CD19
CD138
IL-10
cells dramatically decreased allergic airway inflammation in wild-type and Sema4c
mice. This study identifies a novel pathway by which Th2-mediated immune responses are regulated. It highlights the importance of plasma cells as regulatory cells in allergic inflammation and suggests that CD138
B cells contribute to cytokine balance and are important for maintenance of immune homeostasis in allergic airways disease. Furthermore, we demonstrate that Sema4C is critical for optimal regulatory cytokine production in CD138
B cells.
IVIg is widely used as an immunomodulatory therapy. We have recently demonstrated that IVIg protects against airway hyperresponsiveness (AHR) and inflammation in mouse models of allergic airways ...disease (AAD), associated with induction of Foxp3
regulatory T cells (Treg). Using mice carrying a
transgene under the control of the
promoter (DEREG mice), we demonstrate in this study that IVIg generates a de novo population of peripheral Treg (pTreg) in the absence of endogenous Treg. IVIg-generated pTreg were sufficient for inhibition of OVA-induced AHR in an Ag-driven murine model of AAD. In the absence of endogenous Treg, IVIg failed to confer protection against AHR and airway inflammation. Adoptive transfer of purified IVIg-generated pTreg prior to Ag challenge effectively prevented airway inflammation and AHR in an Ag-specific manner. Microarray gene expression profiling of IVIg-generated pTreg revealed upregulation of genes associated with cell cycle, chromatin, cytoskeleton/motility, immunity, and apoptosis. These data demonstrate the importance of Treg in regulating AAD and show that IVIg-generated pTreg are necessary and sufficient for inhibition of allergen-induced AAD. The ability of IVIg to generate pure populations of highly Ag-specific pTreg represents a new avenue to study pTreg, the cross-talk between humoral and cellular immunity, and regulation of the inflammatory response to Ags.
Tregitopes (T regulatory epitopes) are IgG-derived peptides with high affinity to major histocompatibility complex class II (MHCII), that are known to promote tolerance by activating T regulatory ...cell (Treg) activity. Here we characterized the effect of IgG Tregitopes in a well-established murine model of allergic asthma, demonstrating
antigen-specific tolerance
adoptive transfer of Tregitope-and-allergen-activated Tregs. Asthma is a heterogeneous chronic inflammatory condition affecting the airways and impacting over 300 million individuals worldwide. Treatment is suppressive, and no current therapy addresses immune regulation in severely affected asthmatics. Although high dose intra-venous immunoglobulin (IVIg) is not commonly used in the asthma clinic setting, it has been shown to improve severe asthma in children and in adults. In our laboratory, we previously demonstrated that IVIg abrogates airway hyperresponsiveness (AHR) in a murine model of asthma and induces suppressive antigen-specific T-regulatory cells. We hypothesized that IgG-derived Tregitopes would modulate allergic airway disease by inducing highly suppressive antigen-specific Tregs capable of diminishing T effector cell responses and establishing antigen-specific tolerance. Using ovalbumin (OVA-) and ragweed-driven murine models of allergic airway disease, we characterized the immunoregulatory properties of Tregitopes and performed Treg adoptive transfer to OVA- and ragweed-allergic mice to test for allergen specificity. Treatment with Tregitopes attenuated allergen-induced airway hyperresponsiveness and lung inflammation. We demonstrated that Tregitopes induce highly suppressive allergen-specific Tregs. The tolerogenic action of IgG Tregitopes in our model is very similar to that of IVIg, so we foresee that IgG Tregitopes could potentially replace steroid-based treatment and can offer a synthetic alternative to IVIg in a range of inflammatory and allergic conditions.
We analyzed genetic data of 47,429 multiple sclerosis (MS) and 68,374 control subjects and established a reference map of the genetic architecture of MS that includes 200 autosomal susceptibility ...variants outside the major histocompatibility complex (MHC), one chromosome X variant, and 32 variants within the extended MHC. We used an ensemble of methods to prioritize 551 putative susceptibility genes that implicate multiple innate and adaptive pathways distributed across the cellular components of the immune system. Using expression profiles from purified human microglia, we observed enrichment for MS genes in these brain-resident immune cells, suggesting that these may have a role in targeting an autoimmune process to the central nervous system, although MS is most likely initially triggered by perturbation of peripheral immune responses.
Multiple sclerosis is a complex neurological disease, with ∼20% of risk heritability attributable to common genetic variants, including >230 identified by genome-wide association studies. Multiple ...strands of evidence suggest that much of the remaining heritability is also due to additive effects of common variants rather than epistasis between these variants or mutations exclusive to individual families. Here, we show in 68,379 cases and controls that up to 5% of this heritability is explained by low-frequency variation in gene coding sequence. We identify four novel genes driving MS risk independently of common-variant signals, highlighting key pathogenic roles for regulatory T cell homeostasis and regulation, IFNγ biology, and NFκB signaling. As low-frequency variants do not show substantial linkage disequilibrium with other variants, and as coding variants are more interpretable and experimentally tractable than non-coding variation, our discoveries constitute a rich resource for dissecting the pathobiology of MS.
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•Almost 20% of MS risk heritability can be attributed to common genetic variants•We show that nearly 5% of heritability is explained by coding low-frequency variants•We identify four novel genes driving risk independently of common-variant signals•These genes would not have been found by common-variant studies
In a large multi-cohort study, unexplained heritability for multiple sclerosis is detected in low-frequency coding variants that are missed by GWAS analyses, further underscoring the role of immune genes in MS pathology.
Inhaled oxidative toxicants present in ambient air cause airway epithelial injury, inflammation, and airway hyperresponsiveness. Effective adaptation to such environmental insults is essential for ...the preservation of pulmonary function, whereas failure or incomplete adaptation to oxidative injury can render the host susceptible to the development of airway disease.
We sought to explore the mechanisms of airway adaptation to oxidative injury.
For a model to study pulmonary adaptation to oxidative stress–induced lung injury, we exposed mice to repeated nose-only chlorine gas exposures. Outcome measures were evaluated 24 hours after the last chlorine exposure. Lung mechanics and airway responsiveness to methacholine were assessed by using the flexiVent. Inflammation and antioxidant responses were assessed in both bronchoalveolar lavage fluid and lung tissue. Using both loss or gain of function and genomic approaches, we further dissected the cellular and molecular mechanisms involved in pulmonary adaptation.
Repeated exposures to oxidative stress resulted in pulmonary adaptation evidenced by abrogation of neutrophilic inflammation and airway hyperresponsiveness. This adaptation was independent of antioxidant mechanisms and regulatory T cells but dependent on residential alveolar macrophages (AMs). Interestingly, 5% of AMs expressed forkhead box P3, and depletion of these cells abolished adaptation. Results from transcriptomic profiling and loss and gain of function suggest that adaptation might be dependent on TGF-β and prostaglandin E2.
Pulmonary adaptation during oxidative stress–induced lung injury is mediated by a novel subset of forkhead box P3–positive AMs that limits inflammation, favoring airway adaptation and host fitness through TGF-β and prostaglandin E2.
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Background:
Vitamin D insufficiency is a risk factor for multiple sclerosis (MS), and patients do not always show the expected response to vitamin D supplementation.
Objective:
We aimed to determine ...if vitamin D supplementation leads to a similar increase in serum 25-hydroxyvitamin-D (25(OH)D) levels in patients with MS and healthy controls (HCs).
Methods:
Participants in this open-label study were female, white, aged 18–60 years, had 25(OH)D levels ⩽ 75 nmol/l at screening, and had relapsing–remitting MS (RRMS) or were HCs. Participants received 5000 IU/day of vitamin D3 for 90 days. Utilizing generalized estimating equations we examined the relationship between the primary outcome (serum 25(OH)D level) and the primary (MS versus HC status) and secondary predictors.
Results:
For this study 27 MS patients and 30 HCs were enrolled. There was no significant difference in baseline 25(OH)D level or demographics except for higher body mass index (BMI) in the MS group (25.3 vs. 23.6 kg/m2, p=0.035). In total, 24 MS subjects and 29 HCs completed the study. In a multivariate model accounting for BMI, medication adherence, and oral contraceptive use, MS patients had a 16.7 nmol/l (95%CI: 4.2, 29.2, p=0.008) lower increase in 25(OH)D levels compared with HCs.
Conclusions:
Patients with MS had a lower increase in 25(OH)D levels with supplementation, even after accounting for putative confounders.
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