CD4+ FOXP3+ Regulatory T Cells Exhibit Impaired Ability to Suppress Effector T Cell Proliferation in Patients with Turner Syndrome

Investigating sex differences in T regulatory cells from cisgender and transgender healthy individuals and patients with autoimmune inflammatory disease: a cross-sectional study

Background

Sexual dimorphisms, which vary depending on age group and pubertal status, have been described across both the innate and adaptive immune system. We explored the influence of sex hormones on immune phenotype in the context of adolescent health and autoimmunity.

Methods

In this cross-sectional study, healthy, post-pubertal cisgender individuals (aged 16-25 years); healthy, pre-pubertal cisgender individuals (aged 6-11 years); transgender individuals (aged 18-19 years) undergoing gender-affirming treatment (testosterone in individuals assigned female sex at birth and oestradiol in individuals assigned male sex at birth); and post-pubertal cisgender individuals (aged 14-25 years) with juvenile-onset systemic lupus erythematosus (SLE) age-matched to cisgender individuals without juvenile-onset SLE were eligible for inclusion. Frequencies of 28 immune-cell subsets (including different T cell, B cell, and monocyte subsets) from each participant were measured in peripheral blood mononuclear cells by flow cytometry and analysed by balanced random forest machine learning. RNA-sequencing was used to compare sex and gender differences in regulatory T (Treg) cell phenotype between participants with juvenile-onset SLE, age-matched cis-gender participants without the disease, and age matched transgender individuals on gender-affirming sex hormone treatment. Differentially expressed genes were analysed by cluster and pathway analysis. Suppression assays assessed the anti-inflammatory function of Treg cells in vitro.

Findings

Between Sept 5, 2012, and Nov 6, 2019, peripheral blood was collected from 39 individuals in the post-pubertal group (17 [44%] cisgender men, mean age 18·76 years [SD 2·66]; 22 [56%] cisgender women, mean age 18·59 years [2·81]), 14 children in the cisgender pre-pubertal group (seven [50%] cisgender boys, mean age 8·90 [1·66]; seven [50%] cisgender girls, mean age 8·40 [1·58]), ten people in the transgender group (five [50%] transgender men, mean age 18·20 years [0·47]; five [50%] transgender women, mean age 18·70 years [0·55]), and 35 people in the juvenile-onset SLE group (12 [34%] cisgender men, mean age 18·58 years [2·35]; 23 [66%] cisgender women, mean age 19·48 [3·08]). Statistically significantly elevated frequencies of Treg cells were one of the top immune-cell features differentiating young post-pubertal cisgender men from similarly aged cisgender women (p=0·0097). Treg cells from young cisgender men had a statistically significantly increased suppressive capacity in vitro compared with those from cisgender women and a distinct transcriptomic signature significantly enriched for genes in the PI3K-AKT signalling pathway. Gender-affirming sex hormones in transgender men and transgender women induced multiple statistically significant changes in the Treg-cell transcriptome, many of which enriched functional pathways that overlapped with those altered between cisgender men and cisgender women, highlighting a hormonal influence on Treg-cell function by gender. Finally, sex differences in Treg-cell frequency were absent and suppressive capacity was reversed in patients with juvenile-onset SLE, but sex differences in Treg-cell transcriptional signatures were significantly more pronounced in patients with juvenile-onset SLE compared with individuals without juvenile-onset SLE, suggesting that sex hormone signalling could be dysregulated in autoimmunity.

Interpretation

Sex-chromosomes and hormones might drive changes in Treg-cell frequency and function. Young post-pubertal men have a more anti-inflammatory Treg-cell profile, which could explain inflammatory disease susceptibilities, and inform sex-tailored therapeutic strategies.

Funding

Versus Arthritis, UK National Institute for Health Research University College London Hospital Biomedical Research Centre, Lupus UK, and The Rosetrees Trust.

Immunological Profile and Autoimmunity in Turner Syndrome

Turner syndrome (TS), characterized by the partial or complete absence of an X-chromosome, provides a unique insight into the role of the X-chromosome and the immune system. While women have a 10-fold higher incidence of autoimmune disease (AD) compared with men, the risk in women with TS is thought to be further doubled. TS is associated with a propensity for a wide variety of ADs that increase in incidence across the life span. Isochromosome Xq as well as isolated Xp deletion karyotypes may predispose to higher rates of AD in TS suggesting the impact of X-chromosome gene dosage. It is likely, however, that epigenetic changes across the genome and the hormonal milieu may also have a profound impact on the immune profile in TS. This review explores the immune phenotype and the spectrum of ADs in TS. Genotype-phenotype correlations are presented with a brief overview of the genetic and hormonal underpinnings.

4-phenylbutyric acid mediates therapeutic effect in systemic lupus erythematosus: Observations in an experimental murine lupus model

Impaired function of regulatory T cells (Tregs) contributes to the pathogenesis of systemic lupus erythematosus (SLE). Our previous study demonstrated aberrant responses of T lymphocytes to endoplasmic reticulum (ER) stress in patients with SLE. The present study investigated whether ER stress inhibition by 4-phenylbutyric acid (4-PBA) ameliorated lupus manifestations in an experimental lupus model and the effect of ER stress inhibition on the frequency and function of Tregs. A murine lupus model was induced through a 4-week treatment with Resiquimod, a toll-like receptor (TLR) 7 agonist. From the 8th week, the mice were treated with 4-PBA for 4 weeks. 4-PBA significantly decreased the levels of anti-dsDNA antibodies and serum TNF-α. A significant decrease in glomerulonephritis score was also observed in the 4-PBA-treated group. ER stress inhibition decreased the activated T and B lymphocytes population of splenocytes; however, the population of Tregs was not significantly different between the vehicle and 4-PBA group. However, a markedly enhanced suppressive capacity of Treg was detected in the 4-PBA-treated group. The present results suggest that ER stress inhibition attenuated disease activity in an experimental model by improving the suppressive capacity of Tregs. Therefore, reduction of ER stress could be used as a beneficial therapeutic strategy in SLE.

Hashimoto's Thyroiditis and Graves' Disease in Genetic Syndromes in Pediatric Age

Autoimmune thyroid diseases (AITDs), including Hashimoto’s thyroiditis (HT) and Graves’ disease (GD), are the most common cause of acquired thyroid disorder during childhood and adolescence. Our purpose was to assess the main features of AITDs when they occur in association with genetic syndromes. We conducted a systematic review of the literature, covering the last 20 years, through MEDLINE via PubMed and EMBASE databases, in order to identify studies focused on the relation between AITDs and genetic syndromes in children and adolescents. From the 1654 references initially identified, 90 articles were selected for our final evaluation. Turner syndrome, Down syndrome, Klinefelter syndrome, neurofibromatosis type 1, Noonan syndrome, 22q11.2 deletion syndrome, Prader–Willi syndrome, Williams syndrome and 18q deletion syndrome were evaluated. Our analysis confirmed that AITDs show peculiar phenotypic patterns when they occur in association with some genetic disorders, especially chromosomopathies. To improve clinical practice and healthcare in children and adolescents with genetic syndromes, an accurate screening and monitoring of thyroid function and autoimmunity should be performed. Furthermore, maintaining adequate thyroid hormone levels is important to avoid aggravating growth and cognitive deficits that are not infrequently present in the syndromes analyzed.

Autoimmune Thyroid Disease in Specific Genetic Syndromes in Childhood and Adolescence

Autoimmune thyroid disease (ATD) is the most frequent cause of acquired thyroid dysfunction, most commonly presenting either as Hashimoto's thyroiditis or Graves' Disease. Hashimoto's thyroiditis is characterized by the presence of thyroid-specific autoantibodies, more commonly anti-thyroperoxidase antibodies in the serum and the typical inhomogeneous echostructure of the thyroid on a thyroid ultrasound examination. Hashimoto's thyroiditis can for a long time be accompanied by normal thyroid function and hypothyroidism can only progressively be established. Graves' disease is much less frequent in childhood and adolescence and presents with overt hyperthyroidism. After the onset of puberty, ATD affects females with a higher incidence than males, while during the prepubertal period there is not such a clear preponderance of affected females. ATD can occur either isolated or in the context of other autoimmune disorders, such as type 1 Diabetes mellitus (T1D), celiac disease, alopecia areata, vitiligo, etc. Especially at the pediatric age, a higher incidence of ATD is also observed in the context of specific genetic syndromes, such as trisomy 21 (Down syndrome), Klinefelter syndrome, Turner syndrome, or 22q11.2 deletion syndrome. Nevertheless, although thyroid dysfunction may also be observed in other genetic syndromes, such as Prader-Willi or Williams syndrome, the thyroid dysfunction in these syndromes is not the result of thyroid autoimmunity. Interestingly, there is emerging evidence supporting a possible link between autoimmunity and RASopathies. In this review article the incidence, as well as the clinical manifestation and accompanied pathologies of ATD in specific genetic syndromes will be presented and regular follow-up for the early identification of the disorder will be proposed.

Treg-promoted New Bone Formation Through Suppressing TH17 by Secreting Interleukin-10 in Ankylosing Spondylitis

STUDY DESIGN

Retrospective single-center study.

OBJECTIVE

We want to know whether interleukin (IL)-10-secreting regulatory T cells (Treg) promote the new bone formation (NBF) through suppressing TH17 in ankylosing spondylitis (AS).

SUMMARY OF BACKGROUND DATA

NBF in AS is unknown. Since there are balances of bone remodeling in human body and proinflammatory helper T cells TH17 promoted bone resorption.

METHODS

Eighteen AS patients with or without NBF (both nine cases) and nine healthy individuals were selected and the demographic data, Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), MRI sacroiliitis score (MRISIS), and computer tomography sacroiliitis score (CTSIS) were recorded. Removed hip ligament tissue in the lesions after arthroplasty was collected and the lymphocytes and the peripheral blood mononuclear cells were prepared. Second, pathological section in hematoxylin-eosin stain were analyzed and flow cytometry and quantitative polymerase chain reaction analyses were carried out to detect the levels of TH17, Treg, IL-10, and nuclear factor (NF)-κB, and the relevance between them. The effect of Treg on TH17 was further analyzed by using Transwell coculturing.

RESULTS

Compared to AS patients without NBF, AS patients with NBF had significantly higher CTSIS and complications (P < 0.05 and 0.01, respectively), but significantly lower BASDAI (3.0 ± 0.4) and MRISIS (3.3 ± 0.8) (P < 0.01 and 0.05, respectively) and no acute inflammation in HE stain for hip joint. Compared to healthy donors, the ratio of TH17/Treg was significantly higher in AS patients without NBF and lower in AS patient with NBF (both P < 0.01) in flow cytometry analysis (FCA). Furthermore, TH17 significantly decreased after indirectly coculturing with Treg in FCA (P < 0.01). Finally, IL-10 had significantly higher mRNA expression in AS patients with NBF (P < 0.01), and NF-κB had significantly higher mRNA expression in AS patients without NBF (P < 0.05) than healthy donors. Only the mRNA expression of IL-10 was significantly correlated to the ratio of TH17/Treg (r = -0.93, P < 0.01).

CONCLUSION

Treg-induced NBF of AS through suppressing TH17 by secreting IL10 and declining of the ratio of TH17/Treg indicated the development of NBF. This is important not only for screening development of NBF, but also for control of NBF of AS by immune therapy.

LEVEL OF EVIDENCE

N/A.

A child with Klinefelter syndrome and both IgE-mediated food allergy and low proportion of naive Treg

This case suggests a possible association between Klinefelter Syndrome and decreased regulatory T cells (Treg) cells, relating to an increased risk of allergic and autoimmune disorders in these patients. The immune phenotyping of the circulating FOXP3+ naive Treg populations in KS patients may help to indicate this predisposition.

Autoimmunity Predisposition in Girls With Turner Syndrome

Background: Turner Syndrome is associated with an increased risk of autoimmune diseases, such as autoimmune thyroiditis, coeliac disease, type 1 diabetes mellitus, inflammatory bowel disease, alopecia areata, or vitiligo. The presence of isochromosome iXq and exposure to estradiol may contribute to the development of the autoimmune process. The aim of this study was to determine the prevalence of autoimmune diseases in a group of TS patients and to assess the impact of karyotype and puberty on the development of autoimmune diseases. Patients and Methods: The analysis encompassed clinical and biochemical data of 134 patients treated between 2001 and 2018. All the patients were examined for autoimmune disease symptoms and tested for the presence of antithyroperoxidase (anti-TPO) and antithyreoglobulin (anti-TG) antibodies. In 73 of the patients, anti-transglutaminase (anti-tTG) antibodies were measured. Thyroid function was assessed by measuring TSH and fT4 levels. Results: The mean follow-up was 5.7 ± 3 years. An autoimmune disease was diagnosed in 46 (34.3%) patients: 39 (29.1%) had only one disorder, whilst 7 (5.2%) presented two disorders. The most common disorder, observed in 40 (29.9%) patients, was thyroid autoimmunity. Hashimoto disease was diagnosed in 20 (14.9%) patients. Of the 73 patients tested for coeliac disease, 4 (5.5%) had anti-tTG and 2 (2.7%) presented overt coeliac disease. Vitiligo was diagnosed in 3 (2.2%) patients, type 1 diabetes mellitus or psoriasis were diagnosed in 2 (1.5%) patients, whilst alopecia areata or lichen sclerosus were diagnosed in 1 (0.7%) patient. The impact of karyotype or estradiol exposure on developing autoimmune diseases were not statistically significant. Conclusions: Our study showed a higher incidence of autoimmune diseases in TS, which is in line with the literature; however, the impact of iXq, or spontaneous/inducted puberty was not confirmed.

Epigenetic Dysfunction in Turner Syndrome Immune Cells

Turner syndrome (TS) is a chromosomal condition associated with partial or complete absence of the X chromosome that involves characteristic findings in multiple organ systems. In addition to well-known clinical characteristics such as short stature and gonadal failure, TS is also associated with T cell immune alterations and chronic otitis media, suggestive of a possible immune deficiency. Recently, ubiquitously transcribed tetratricopeptide repeat on the X chromosome (UTX), a histone H3 lysine 27 (H3K27) demethylase, has been identified as a downregulated gene in TS immune cells. Importantly, UTX is an X-linked gene that escapes X-chromosome inactivation and thus is haploinsufficient in TS. Mice with T cell-specific UTX deficiency have impaired clearance of chronic viral infection due to decreased frequencies of T follicular helper (Tfh) cells, which are critical for B cell antibody generation. In parallel, TS patients have decreased Tfh frequencies in peripheral blood. Together, these findings suggest that haploinsufficiency of the X-linked UTX gene in TS T cells underlies an immune deficit, which may manifest as increased predisposition to chronic otitis media.