The Roles of Exosomes in Immunoregulation and Autoimmune Thyroid Diseases.

Exosomes are extracellular microvesicles (30-150 nm) released from cells that contain proteins, lipids, RNA and DNA. They can deliver bioactive molecules and serve as carriers facilitating cell-cell communication, such as antigen presentation, inflammatory activation, autoimmune diseases (AIDs) and tumor metastasis. Recently, much attention has been attracted to the biology and functions of exosomes in immune regulation and AIDs, including autoimmune thyroid diseases (AITDs). Some studies have shown that exosomes are involved in the occurrence and development of AITDs, but they are still in the preliminary stage of exploration. This review mainly introduces the association of exosomes with immune regulation and emphasizes the potential role of exosomes in AITDs, aiming to provide new research strategies and directions for the pathogenesis and early diagnosis of AITDs.

Neutrophil-to-lymphocyte ratio, monocyte-to-lymphocyte ratio, and platelet-tolymphocyte ratio in different etiological causes of thyrotoxicosis

Background/aim: The most common causes of thyrotoxicosis include Graves' disease (GD), toxic multinodular goiter (TMNG), toxic adenoma (TA), and subacute granulomatous thyroiditis (SAT). In our study, we aimed to see whether neutrophil­to­lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), platelet­to­lymphocyte ratio (PLR), and mean platelet volume (MPV) may be helpful in the differential diagnosis of these diseases. Materials and methods: We retrospectively analyzed the hospital records of the Endocrinology Clinic of our hospital between 2016 and 2019. We included data from 66 GD, 37 TA, and 35 SAT patients. We compared the data with those of 35 healthy subjects as controls. Results: NLR, MLR, and PLR were found to be higher in the SAT group when compared to other groups. The post hoc analysis of comparison of NLR, MLR, and PLR in each group showed that NLR and PLR were significantly different in the SAT group when compared to the GD, TA, and controls groups (P < 0.001, P = 0.003, and P < 0.001 for NLR respectively and P < 0.001 for PLR in all groups). MPV levels were different between groups (P = 0.007). However, the intergroup analysis (Tukey's test) failed to show a statistically significant difference for any of the groups. In patients with SAT, PLR and NLR were significantly higher than in the GD, TA, and control groups. MLR was also higher in SAT when compared to other groups, but the difference was not statistically significant. Conclusion: High PLR and NLR may be helpful to differentiate SAT from GD and TA, the other common causes of thyrotoxicosis.

Indicators of immunological and hormonal research in patients with non-hospital pneumonia-liquidators of the Chernobyl accident after treatment.

AIM: The aim of the study is to study the state of the immunological and hormonal background in patients with non-hospital pneumonia (NP) - liquidators of the accident at the Chernobyl nuclear power plant (ChNPP) after treatment. MATERIALS AND METHODS: Patients with NP were divided into 2 groups of liquidators of the Chernobyl accident (main group), patients with NP who did not participate in liquidation of the Chernobyl accident (control group), which determined immunological parameters [CD3+, CD4+, CD8+, CD16+, CD20+ expressing cells, immunoglobulin concentrations (Ig) A, M, G] and hormonal indicators (antibodies to thyroglobulin, thyroglobulin, triiodothyronine, thyroxin, cortisol, insulin, testosterone, estradiol, estriol). The main group - liquidators of the Chernobyl accident in an immunological study of 32 NP patients, hormonal - 20; control group - respectively 37 and 38. RESULTS: Combined therapy contributed to an increase in T-lymphocytes in the main and control groups, as well as T-suppressors (Tc) and T-helper cells (Tx), respectively (p<0.05). Also increased the content of B-lymphocytes, IgA, IgM, complement and phagocytic activity in the main and control groups. The ratio Tx/Tc decreased, also decreased IgG, load index, zero cells in the main and control groups.The study of hormonal background in patients with NP showed that the content of thyroglobulin after complex therapy in the main group increased, in the control group their content did not change. The content of triiodothyronine and thyroxine increased after treatment in the main group. In patients with NP of the control group, on the contrary, there was a decrease in thyroid function in terms of thyroglobulin. The study of sex hormones showed that the content of testosterone, estradiol, estriol in patients with NP of the main group increased after treatment, whereas in the control group there was a decrease in estradiol confidence, and testosterone level remained unchanged. The content of estriol increased (p<0.001) in the control group. The increased amount of insulin decreased (p<0.01) in the main group, whereas in the control group these indicators almost did not change. CONCLUSION: After complex therapy, immunological parameters in NP patients in both the main and control groups are normalized, however, recovery in the main group is slower, which requires continued immunological correction in the outpatient setting. Hormonal background approaching the norm more in patients with NP of the control group than the main one.

[The choice of surgery in patients with diffuse toxic goiter]. / Vybor ob''ema operatsii u bol'nykh diffuznym toksicheskim zobom (s kommentariem).

AIM: to define clear individual indications for different operations for diffuse toxic goiter by research of immunological markers of thyrotoxicosis recurrence probability. MATERIAL AND METHODS: Long-term results of survey and treatment of 215 patients with diffuse toxic goiter are presented. Patients were divided into 2 groups. The 1st group consisted of 31 patienrs who underwent conventional partial thyroidectomy. Group 2 included 184 patients. They were divided into 2 subgroups depending on type of surgery. Subgroup A included 59 patients after partial thyroidectomy and subgroup B - 125 patients after total thyroidectomy. In group 2 surgery was defined based on only level of antibodies against TSH-receptors. RESULTS: Recurrence incidence was 16 and 0% in groups 1 and 2 respectively. CONCLUSION: In patients with diffuse toxic goiter partial thyroidectomy is possible if normal titer of antibodies against TSH-receptors is present (<1.5 U/l). Total thyroidectomy is advisable in titer ≥1.5 U/l.

Does TSH Trigger the Anti-thyroid Autoimmune Processes? Observation on a Large Cohort of Naive Patients with Thyroid Hemiagenesis.

Thyroid hemiagenesis (THA) is a rare abnormality characterized by the absence of one thyroid lobe. Elevated thyroid stimulating hormone (TSH) level and higher incidence of thyroid diseases were reported in THA. The aim of the study is to evaluate the thyroid autoimmunity incidence in patients with THA and influence of higher than average TSH level on thyroid volume (TV) and its change with age. The study included a group of naive patients with THA and a control group of subjects with bilobate thyroid. All patients underwent clinical examination, thyroid ultrasound, scintiscan and laboratory tests. In the studied and control group the presence of thyroid autoantibodies (TAb) was evaluated. The THA group consisted of 65 patients. In THA group 53.85 % of patients were positive for TAb. Patients with positive TAb were older (46.0 ± 18.3 years) than those with negative (35.0 ± 19.8 years); p = 0.02. The incidence of TAb was lower in controls (13.85 %, p < 0.0001). In the study group, positive correlation between the age and TV (r = 0.46, p = 0.0001), and negative correlations between the age and TSH level (r = -0.31, p = 0.01), and TSH concentration and TV (r = -0.35, p = 0.004) were found. In a subgroup of 30 patients with THA negative for TAb, even stronger correlations were observed. The median single lobe volume and median TSH level were higher in patients with THA when compared to controls (13.60 vs 8.20 ml, p < 0.0001; 3.23 vs 1.48 µU/ml, p < 0.0001, respectively). Patients with THA constitute an in vivo model of long-term thyroid TSH overstimulation. Further studies are needed to reveal, whether TSH overstimulation may be the trigger for thyroid autoimmunity.

Thyroid autoimmune disorders in patients with acromegaly.

PURPOSE: Disorders of the hypothalamic-pituitary-thyroid axis are common in patients with acromegaly and thyroid enlargement is present in the majority of them. The exact prevalence of goiter in patients with acromegaly remains uncertain and the presence of thyroid autoimmunity has not been extensively evaluated so far. METHODS: We retrospectively evaluated thyroid biochemical and morphological findings in 116 acromegalic patients who attended our hospital. Serum TSH, total thyroxine levels and anti-thyroid peroxidase (ATPO) antibodies were measured by standard ultrasensitive techniques in all the patients. Thyroid ultrasound was performed in 75 out of them. The antibody control group was composed by healthy Argentinean individuals who attended the blood bank of our hospital in whom ATPO antibodies were measured. RESULTS: Twenty-nine out of the 116 acromegalic patients (25 %) showed elevated titers of thyroid antibodies (79 % were women and 21 % men). The control group had a 10 % prevalence of thyroid autoimmunity. The prevalence of goiter by ultrasound was 36 %, being more common in females (41 %) than in males (28 %). Thirty-five percent of patients who presented thyroid nodules and 44 % of patients with ultrasound diagnosed goiters had positive thyroid autoimmunity. There was no significant correlation between the presence of nodules and IGF-1 levels, duration of disease or age. CONCLUSION: We found a high prevalence of thyroid autoimmunity in our patients with acromegaly as compared to the normal population. Thyroid autoimmunity seems to be an additional mechanism for the development of thyroid disorders in acromegaly.

Graves' disease is associated with a defective expression of the immune regulatory molecule galectin-9 in antigen-presenting dendritic cells.

INTRODUCTION: Patients with autoimmune thyroid disease (AITD) show defects in their immune-regulatory mechanisms. Herein we assessed the expression and function of galectin-1 and galectin-9 (Gal-1, Gal-9) in dendritic cells (DCs) from patients with AITD. MATERIALS AND METHODS: Peripheral blood samples from 25 patients with Graves' disease (GD), 11 Hashimoto's thyroiditis (HT), and 24 healthy subjects were studied. Thyroid tissue samples from 44 patients with AITD and 22 patients with goiter were also analyzed. Expression and function of Gal-1 and Gal-9 was assessed by quantitative RT-PCR, immunofluorescence and flow cytometry. RESULTS: A diminished expression of Gal-9, but not of Gal-1, by peripheral blood DCs was observed in GD patients, mainly in those with Graves´ ophthalmopathy, and a significant negative association between disease severity and Gal-9 expression was detected. In addition, the mRNA levels of Gal-9 and its ligand TIM-3 were increased in thyroid tissue from AITD patients and its expression was associated with the levels of Th1/Th12/Th17 cytokines. Immunofluorescence studies proved that intrathyroidal Gal-9 expression was confined to DCs and macrophages. Finally, in vitro functional assays showed that exogenous Gal-9 had a suppressive effect on the release of Th1/Th2/Th17 cytokines by DC/lymphocyte autologous co-cultures from both AITD patients and healthy controls. CONCLUSIONS: The altered pattern of expression of Gal-9 in peripheral blood DCs from GD patients, its correlation with disease severity as well as its ability to suppress cytokine release suggest that Gal-9 could be involved in the pathogenesis of AITD.

Histopathological characteristics of human non-tumor thyroid tissues in a long-term model of adenomatous goiter xenografts in the NOD/Shi-scid, IL-2Rγ(null) mouse.

There is a growing need for modeling the human thyroid to link data obtained from animals to humans because of its sensitivity to radiation exposure and endocrine disruption chemicals. In a scid mouse model produced by transplanting human thyroid tissues, leakiness and thymic lymphoma that occurs spontaneously in the scid mouse can complicate the interpretation of experimental results. Considering that the NOD.Cg-Prkdc(scid)Il2rg(tm1Sug)/Jic mouse (NOD/Shi-scid, IL-2Rγ(null) or NOG mouse) may be a better host because this strain has low incidence of leakiness and thymic lymphoma, we have evaluated the potential of a model that allows long-term observation of non-tumor human thyroid tissues in this mouse. We transplanted tissues of human adenomatous goiter into NOG mice and examined the tissues histopathologically. The morphology of human adenomatous goiter tissues was maintained from 24 to 44 weeks after transplantation in NOG mice with no noted differences between donor-matched tissues or the weeks after transplantation. The tissues expressed thyroglobulin protein and mRNA as well as thyroperoxidase. Endothelial cells originating from human were found in the transplanted tissues and were thought to be a characteristic of this model. The intactness of the tissues before transplantation was found to affect the rate of tissue engraftment. From the present results we have concluded that transplanted thyroid tissues in NOG mice maintain the histopathological characteristics of their origin for long terms. Therefore this model was thought feasible for toxicity evaluation.

Benign thyroid disease is associated with breast cancer: a meta-analysis.

The controversial relationship between benign thyroid diseases and breast cancer (BC) has been investigated for over 50 years. Despite extensive population studies, the results as a whole have been inconsistent. The purpose of this study was to collate and analyse available data, calculating a pooled odds ratio (OR) of the risk of BC in patients diagnosed with benign thyroid diseases. Studies were obtained from a database search of MEDLINE, EMBASE, PubMed, Current Contents Connect and Google Scholar with additional cross checking of reference lists. Inclusion criteria required a confirmed diagnosis of a benign thyroid disease, reporting of an OR or data to calculate an OR (and 95% confidence interval, CI) and the use of an internal control group as the comparator. Collated data was assessed for heterogeneity and a pooled OR calculated. 28 studies were included in the meta-analysis. There was significant evidence of an increased risk of BC in patients with autoimmune thyroiditis, evident in a pooled OR 2.92 (95% CI 2.13-4.01). In addition, the results supported an increased risk associated with the presence of anti-thyroid antibodies (OR 2.02, 95% CI 1.63-2.50) and goitre (OR 2.26, 95% CI 1.39-3.69). Subgroup analysis of antibody presence revealed increased risk associated with both anti-TPO (OR 2.64, 95% CI 1.82-3.83) and anti-TG (2.71, 95% CI 1.58-4.69). Quantitative analysis of hypothyroidism and hyperthyroidism was not significant. While these results indicate an association between thyroid auto-immunity and BC, further prospective studies are required to definitively prove causality.

Evidence of a combined cytotoxic thyroglobulin and thyroperoxidase epitope-specific cellular immunity in Hashimoto's thyroiditis.

CONTEXT: Hashimoto's thyroiditis (HT) is a common autoimmune disease leading to thyroid destruction due to lymphocytic infiltration. Only rare data are available regarding the recognition of specific cellular antigens, e.g. of thyroperoxidase (TPO) and thyroglobulin (Tg). OBJECTIVE: The aim of this study was to quantify and characterize TPO- and Tg-epitope-specific CD8-positive T cells of HT patients. DESIGN: Six different human leukocyte antigen (HLA)-A2 restricted, TPO- or Tg-specific tetramers were synthesized and used for measuring CD8-positive T cells in HT patients and controls. RESULTS: The frequency of peripheral TPO- and Tg-specific CD8-positive T cells was significantly higher in HLA-A2-positive HT patients (2.8 ± 9.5%) compared with HLA-A2-negative HT patients (0.5 ± 0.7%), HLA-A2-positive nonautoimmune goiter patients (0.2 ± 0.4%), and HLA-A2-positive healthy controls (0.1 ± 0.2%). The frequency of Tg-specific T cells (3.0%) was very similar to those of TPO-specific CD8-positive T cells (2.9%). Subgroup analyses revealed a steady increase of the number of epitope-specific CD8-positive T cells from 0.6 ± 1.0% at initial diagnosis up to 9.4 ± 18.3% in patients with long-lasting disease. Analyses of the number of thyroid-infiltrating cells as well as the cytotoxic capacity revealed a similar picture for TPO- and Tg-specific T cells. CONCLUSION: We here report for the first time that both antigens, TPO and Tg, are recognized by CD8-positive T cells and are involved in the thyroid destruction process leading to clinical disease manifestation.

Prevalence of autoimmune thyroiditis in patients with polycystic ovary syndrome.

INTRODUCTION: Hypothyroidism is associated with pregnancy complications both for the mother and progeny and it should be considered in reproductive age. Thyroid autoimmunity is stated to be the main cause of hypothyroidism in iodine sufficient areas. Polycystic ovary syndrome (PCOS) is known as the most common endocrine disorder affecting women in reproductive age. Early diagnosis and treatment of hypothyroidism in PCOS may reduce the rate of infertility and pregnancy-related morbidity. In the present study we evaluated thyroid autoimmunity in PCOS patients. METHODS: Over a period of 12 months, 78 patients with PCOS were recruited to this case-control study. Three hundred and fifty age-matched women were studied as a control group. PCOS was defined according to the revised 2003 Rotterdam criteria. Thyroid size was estimated by inspection and palpation. Serum thyroid stimulating hormone (TSH), anti-thyroperoxidase antibody (anti-TPO Ab), and anti-thyroglobulin antibody (anti-Tg Ab) were measured. RESULTS: The mean ± SD of serum anti-TPO Ab in PCOS patients and subjects in the control group was 216 ± 428 and 131 ± 364 IU/mL, respectively (P = 0.04). Prevalence of goiter in PCOS patients was higher than that in control subjects (62.3 vs. 35.7%, P = 0.0001). Serum TSH and anti-Tg Ab in PCOS patients and control subjects did not differ significantly. CONCLUSION: In this case-control study, anti-thyroid antibodies and goiter prevalence were significantly higher in PCOS patients. These data suggest that thyroid exam and evaluation of thyroid function and autoimmunity should be considered in such patients.

Therapy of large multinodular goitre using repeated doses of radioiodine.

OBJECTIVE: To evaluate the efficacy of radioiodine therapy using I in a group of patients with large multinodular goitre (LMG). METHODS: The study was carried out in patients with goitre volume greater than 100 cm and in patients with LMG who were disqualified from surgery. The study included 34 female participants (age range: 62-84 years) with LMG: 26 patients were hyperthyroid and eight patients had a nontoxic goitre. The patients were treated with 800 MBq of radioiodine administered four times at 3-month intervals (total activity of 3.2 GBq). Before each therapy course, serum thyrotropin, free thyroxin, free triiodothyronine and antithyroid antibodies were measured, ultrasonography and thyroid scan were performed. Patients were followed up for a minimum of 24 months. Fine-needle biopsy was done before qualification to the study. RESULTS: Before therapy, median thyroid volume was 145 cm. It decreased during therapy to 65-76 cm after 12 months and to 50-62 cm after 24 months. After 24 months, 60% of patients were euthyroid and 40% of patients were hypothyroid. During therapy, significant increases in TSHRAb, TPOAb and TgAb levels were observed. No correlation between the levels of antithyroid antibodies, radioiodine uptake, reduction of goitre volume and hormonal status was found. CONCLUSION: In most cases of LMG, repeated administration of radioiodine is safe and effective. The highest response of the thyroid volume is observed after the first course of treatment. On account of a high incidence of hypothyroidism, the patients should be monitored during and after therapy.

Evaluation of the role of ultrasonography in diagnosis of autoimmune thyroiditis in goitrous children.

OBJECTIVES: To evaluate the role of thyroid ultrasound in children with autoimmune thyroiditis diagnosed either on cytopathology or by the presence of thyroid peroxidase antibodies. DESIGN AND SETTINGS: Children presenting for the first time to the Thyroid Clinic at the Institute of Nuclear Medicine and Allied Sciences for the complaint of goiter over a two year period (January 2005-December 2006) were studied. SUBJECTS: 695 school children (244 boys and 451 girls) aged 5-18 year were studied. METHODS: Children were subjected to thyroid ultrasound, cytopathology, thyroid peroxidase antibody and thyroid function tests. RESULTS: Overall, 16% of goitrous children had hypoechogenicity on ultrasound, 15.2% had cytopathological evidence of thyroiditis, 10.6% had positive thyroid peroxidase antibodies and 25.2% had abnormal thyroid function tests. Subjects with hypoechogenicity had higher percentage of thyroiditis on cytopathology (41.4% vs. 10.3%; P<0.01), thyroid peroxidase antibody positivity (30.6% vs. 6.8%; P<0.01) and thyroid dysfunction (46.8% vs. 21.2%; P<0.01) than those with normal echogenicity. CONCLUSION: Thyroid USG has a useful, though limited, role in excluding thyroid disease in children. The sensitivity of echogenicity for the diagnosis of autoimmune thyroiditis in children is less than that reported in adults.

Herpes virus antibodies seroprevalence in children with autoimmune thyroid disease.

BACKGROUND: Elevated titers of antibodies against different herpes virus antigens have been reported in some immunodeficient and systemic autoimmune disorders. OBJECTIVE: To examine if Herpes Simplex Virus (HSV), Epstein-Barr virus (EBV), and cytomegalovirus (CMV) IgG and IgM antibodies are detected more frequently in children with autoimmune thyroid disease (AITD) compared to controls. SUBJECTS AND METHODS: Thirty-four children with AITD, aged 9.62 +/- 2.35 years, and 31 matched controls, aged 9.24 +/- 2.98 years, were studied. RESULTS: The percentage of EBV IgG+ children with AITD was statistically higher than the percentage of EBV IgG+ controls (82.35% versus 51.61%, P = 0.008). The percentage of EBV IgG+ children with AITD and hypothyroidism was statistically higher than the percentage of EBV IgG+ children with AITD, without hypothyroidism (100% versus 70%, P = 0.024). No other statistically significant differences were observed in HSV-1+2, and CMV IgG or IgM antibodies between the subgroups of children studied. CONCLUSIONS: EBV seroprevalence is higher in children with AITD compared to controls and the underlying pathology remains to be elucidated.

Factors associated with elevated serum concentrations of anti-TPO antibodies in subjects with and without diffuse goitre. Results from the Ukrainian-American Cohort Study of thyroid cancer and other thyroid diseases following the Chornobyl accident.

OBJECTIVES: To examine factors associated with the prevalence of elevated anti-thyroid peroxidase antibodies (ATPO) among iodine-deficient adolescents and young adults and test whether associations vary according to the presence of diffuse goitre. DESIGN: Subjects were members of the Ukrainian-American Cohort Study exposed to the Chornobyl accident whose (131)I thyroid dose estimates were below 0.2 Gy. MEASUREMENTS: The odds ratios (ORs) for ATPO above 60 U/ml were estimated using logistic regression models for a number of factors in the total population (N = 5133), and separately for thyroid disease-free subjects (N = 3875), those with diffuse goitre (N = 921), and diffuse goitre without autoimmune thyroiditis (AIT; N = 883). RESULTS: Elevated ATPO was found in 9.9% of the total population and ORs were significantly higher in females, older individuals, those examined in earlier calendar years, residents of Kyiv and Chernihiv oblasts, subjects with a family history of thyroid disease, higher thyroid ultrasound volume, suppressed or elevated TSH, blood collection in March to May, very low thyroglobulin (Tg), and shorter serum storage time. When thyroid disease-free subjects and those with diffuse goitre were compared, there were few differences in antibody prevalence, and after excluding individuals with AIT, the only difference was an increased prevalence of elevated ATPO at low urinary iodine in those with goitre alone. CONCLUSIONS: Although a number of factors are associated with the prevalence of elevated ATPO in our study group, with the exception of urinary iodine these factors are independent of goitre, and differences between thyroid disease-free subjects and those with diffuse goitre are largely due to AIT.

Thyroid autoimmunity in the current iodine environment.

Iodine is essential for thyroid function. Thyroid disorders related to iodine deficiency decreased progressively with the continuous iodine prophylaxis and the increased iodine intake. An adverse effect resulting from iodine prophylaxis may be the induction of thyroid autoimmunity. Although experiments performed in animal models suggest that iodine could initiate or exacerbate thyroid autoimmunity, the role of iodine in humans remains controversial. Several observational studies in areas with adequate or high iodine intake suggest that there is an increase in the incidence of thyroid autoimmune disease. Moreover, intervention studies suggest that increased iodine intake may enhance thyroid autoimmunity too. However, not all studies generated the same findings, probably because of genetic, racial, and environmental differences. It seems that autoimmune exacerbation is a transient phenomenon. Studies have shown that in persons presenting thyroid antibodies, the levels of these antibodies progressively decrease when the majority of them react against a nonspecific pattern of thyroglobulin (Tg) epitopes. However, in a small number of these persons, the anti-Tg antibodies are similar to those in patients with patent thyroid autoimmune disease, reacting against specific immunodominant Tg epitopes, and their levels persist. One possible attractive explanation is that enhanced iodine intake increases the antigenicity of Tg through the incorporation of iodine into its molecule and the formation of iodinated Tg epitopes or even the generation of noniodinated pathogenetic Tg epitopes that are normally cryptic.