Analysis of triiodothyronine and thyroxine-binding autoantibodies in chickens susceptible to autoimmune thyroiditis

This report reveals a surprisingly high incidence of thyroid hormone (T3 and T4) autoantibodies (THA) and thyroglobulin autoantibodies in a closed flock of untreated Cornell strain (CS) White Leghorn chickens. This flock is closely related to the Obese strain chicken, which develops a severe spontaneous autoimmune thyroiditis. A sensitive electrophoretic autoradiographic assay for THA was developed. This assay was applied to the study of autoantibodies to T3 and T4 in the sera of adult female CS chickens. Of 109 females, 29.4% had antibodies to T3 and 18.4% had antibodies to T4. The incidence of thyroglobulin antibodies, determined by passive hemagglutination, was 15.6%. The presence of THA affected RIA measurements because serum T3 and T4 hormone concentrations appeared elevated in those birds with moderate to high antibody levels. There was major variance in the electrophoretic heterogeneity of the THA from individual chickens; i.e., some of the sera contained antibodies to T3 or T4 that appeared to be monoclonal, whereas other sera exhibited polyclonal multi-banded patterns. To determine if antibodies reactive with T3 and T4 (which are haptens) were generated by antibody responses to the T3/T4 sites on the thyroglobulin molecule, competitive binding assays were performed to determine the relative binding affinities of the antibodies for the haptens (T3/T4) and the "hapten-conjugate" (thyroglobulin). In these assays, thyroglobulin competed with the haptens, thus supporting the above hypothesis.     

Th1 cytokines in autoimmune thyroiditis

This study was performed on a lot of 51 patients and intends to correlate the autoimmune thyroiditis to the synthesis of Th1 cytokines and to the activation of T lymphocytes. We find out that CD25, an activation marker of T lymphocytes, is significantly increased in these patients. We also find out that certain cytokine serum levels are increased (IL-2, TNF-alpha, IFN-gamma). These cytokines correspond to the secretor profile of the Th1 subset. Mononuclear cell culture supernatants showed an increased level of IL-2 and TNF-alpha in samples stimulated with ConA in comparison to unstimulated samples from the same patient, suggesting the existence of an expansioned Th1 and CD8+ cytotoxic population.     

Selenium in the treatment of autoimmune thyroiditis

We recently conducted a prospective, placebo-controlled clinical study, where we could demonstrate, that a substitution of 200 microg sodium selenite for three months in patients with autoimmune thyroiditis reduced thyroid peroxidase antibody (TPO-Ab) concentrations significantly. Forty-seven patients from the initially 70 patients agreed to participate in a follow-up cross-over study for further six months. One group (n = 13), which initially received selenium continued to take 200 microg sodium selenite (Se-Se), one group stopped taking selenium (Se-0) ( n = 9), another group which received placebo started to take 200 microg selenium (n = 14) (Plac-Se) and the last group was without selenium substitution (Plac-0) (n = 11). TPO-Ab concentrations were measured at beginning and the end of the study. In the Se-Se group, the TPO-Ab concentrations further significantly p = 0.004) decreased from 625 +/- 470 U/ml to 354 +/- 321 U/ml, in the Se-0 group the TPO-Ab concentrations increased significantly p = 0.017) from 450 +/- 335 to 708 +/- 313 U/ml. In the placebo group, the TPO-Ab concentrations in those patients who were followed without selenium substitution were unchanged (1351 +/- 940 vs. 1724 +/- 1112 U/ml, p = 0.555). In contrast, the patients who received 200 microg sodium selenite after placebo, the TPO-Ab concentrations decreased significantly (p = 0.029) from 1182 +/- 723 to 643 +/- 477 U/ml.     

Heterogeneity of autoantibodies in 100 patients with autoimmune myositis: insights into clinical features and outcomes

The objective of this study was to determine the prevalence, mutual associations, clinical manifestations, and diagnoses associated with serum autoantibodies, as detected using recently available immunoassays, in patients with autoimmune myositis (AIM). Sera and clinical data were collected from 100 patients with AIM followed longitudinally. Sera were screened cross-sectionally for 21 autoantibodies by multiplex addressable laser bead immunoassay, line blot immunoassay, immunoprecipitation of in vitro translated recombinant protein, protein A assisted immunoprecipitation, and enzyme-linked immunosorbent assay. Diagnoses were determined using the Bohan and Peter classification as well as recently proposed classifications. Relationships between autoantibodies and clinical manifestations were analyzed by multiple logistic regression. One or more autoantibodies encompassing 19 specificities were present in 80% of the patients. The most common autoantibodies were anti-Ro52 (30% of patients), anti-Ku (23%), anti-synthetases (22%), anti-U1RNP (15%), and anti-fibrillarin (14%). In the presence of autoantibodies to Ku, synthetases, U1RNP, fibrillarin, PM-Scl, or scleroderma autoantigens, at least one more autoantibody was detected in the majority of sera and at least two more autoantibodies in over one-third of sera. The largest number of concurrent autoantibodies was six autoantibodies. Overall, 44 distinct combinations of autoantibodies were counted. Most autoantibodies were unrestricted to any AIM diagnostic category. Distinct clinical syndromes and therapeutic responses were associated with anti-Jo-1, anti-fibrillarin, anti-U1RNP, anti-Ro, anti-Ro52, and autoantibodies to scleroderma autoantigens. We conclude that a significant proportion of AIM patients are characterized by complex associations of autoantibodies. Certain myositis autoantibodies are markers for distinct overlap syndromes and predict therapeutic outcomes. The ultimate clinical features, disease course, and response to therapy in a given AIM patient may be linked to the particular set of associated autoantibodies. These results provide a rationale for patient profiling and its application to therapeutics, because it cannot be assumed that the B-cell response is the same even in the majority of patients in a given diagnostic category.     

Transfer of experimental autoimmune thyroiditis with T cell clones

We have investigated three T lymphocyte clones isolated from CBA/CaJ mice primed with mouse thyroid extract (MTE) in adjuvant. All three clones are L3T4+, Ig-, and Lyt2- and proliferate to MTE, mouse thyroglobulin (MTG) and rat thyroid extract. Clones A7 and B7 transfer thyroiditis to irradiated (475 rad) syngeneic mice, but not to normal recipients. The thyroid lesion induced by the B7 clone is characterized by the infiltration of both mononuclear and polymorphonuclear cells. The thyroiditis is transient in that lesions are apparent 7 and 14 days after transfer, but thyroids return to normal by day 21. Clone B7 showed helper activity for trinitrophenyl-keyhole limpet hemocyanin-primed B cells in vitro when stimulated with trinitrophenyl-MTG and also stimulated the production of anti-MTG antibody in recipient mice. Clone A7 induced thyroid lesions characterized by infiltration of the thyroid with mononuclear cells, with virtually no polymorphonuclear cell infiltration. This clone has shown no helper activity following stimulation with trinitrophenyl-MTG. The third clone (D2) proliferates to and shows helper activity to MTG, but fails to transfer thyroiditis to syngeneic, irradiated mice. On continuous culture, clone B7 lost its surface Thy. The loss of Thy appears unrelated to the ability to transfer thyroiditis since subclones of B7 with markedly different percentages of Thy+ cells transferred disease equally well.     

Occurrence of various autoantibodies in autoimmune diseases

The study aimed at determining the incidence of autoantibodies occurrence in the course of autoimmunological diseases of the thyroid gland and in healthy population. Autoantibodies against various structures were assayed, including: cellular nuclei, smooth muscles, mitochondria, biliary tubules, parietal cells, reticular fibres, striated muscles as well as thyroglobulin and thyroid microsomes. The study involved 63 patients with autoimmunological diseases of the thyroid gland (35 patients with Graves-Basedow disease and 28 patients with Hashimoto's disease) and 30 healthy individuals. Thyroid antimicrosomal and antithyroglobulin antibodies were assayed with RIA in stable phase whereas the remaining antibodies--with multifunctional indirect immunofluorescence test. The obtained results are the following: antimicrosomal antibodies were present in 68.3% cases while antithyroglobulin antibodies in 76.2% of the examined patients with autoimmunological diseases of the thyroid gland. Immunofluorescence tests performed in the same group have shown antinuclear antibodies in 13% of cases, antibodies against smooth muscles in 28.6%, antimitochondrial antibodies in 1.6%, antibodies against biliary tubules in 3.4%, antibodies against parietal cells in 11.1%, antibodies against reticular fibres in 7.9%, and antibodies against striated muscles in 9.5% of cases. Antinuclear antibodies, antibodies against smooth muscles, and antibodies against both thyroidal microsome and thyroglobulin (in 3.3%) were the only antibodies found in the control group.     

Seasonal recurrence of transient hypothyroidism in a patient with autoimmune thyroiditis

Two postpartum and 7 spontaneous episodes of transient hypothyroidism developed during 5 years of observation in a florist with autoimmune thyroiditis and seasonal allergic rhinitis. The spontaneous episodes recurred twice a year regularly in spring and in autumn, the seasons of her allergic rhinitis. In most of these episodes as well as in the postpartum ones, hypothyroidism was preceded by transient thyrotoxicosis. In addition to the similarity in the clinical course, the changes in antimicrosomal antibody titers in pregnancy-unrelated episodes were almost identical to those in postpartum episodes. Throughout the observation periods, she had supranormal serum total immunoglobulin (Ig) E concentrations and high antigen-specific Ig E levels for various pollen extracts such as cedar and ragweed. However, we failed to demonstrate a correlation between thyroid function and total or any antigen-specific Ig E level. The present findings suggest that the pregnancy-unrelated thyroid dysfunction in our patient developed as a result of silent thyroiditis and through similar immunological mechanisms to those in postpartum thyroiditis. And it is suspected, though unproved, that the seasonal recurrence of pregnancy-unrelated thyroiditis has some causal relation to her allergic disease.     

Apoptosis-associated antigens recognized by autoantibodies in patients with the autoimmune liver disease primary biliary cirrhosis

There is growing evidence that the onset of autoimmune disorders can be linked to the inefficient removal of apoptotic cells. Since defects in the elimination of apoptotic cells lead to secondary necrosis and subsequent release of intracellular components, this might explain the generation of autoantibodies against intracellular antigens. Accordingly, we wanted to investigate, whether antibodies from patients with the autoimmune liver disease primary biliary cirrhosis (PBC) recognize self-proteins generated and released during apoptosis. Using Western blot analyses we could detect intracellular antigens with serum IgG from PBC patients but not with serum IgG from healthy donors in lysates of Jurkat T-leukemia, HepG2 hepatoma, and HT-29 colon-carcinoma cells. Interestingly, PBC serum IgG also recognized caspase substrates in cells undergoing apoptosis induced by staurosporine or TRAIL (TNF-related apoptosis inducing ligand). In addition to intracellular antigens, serum IgG from PBC patients detected caspase-dependent antigens in the supernatants of apoptotic (secondary necrotic) cells and antigens on the surface of apoptotic Jurkat cells. Among the caspase substrates recognized by PBC serum IgG we could identify the components PDC-E2 and -E1β of the known autoantigen PDC (pyruvate dehydrogenase complex). Thus, caspase-mediated processing of intracellular proteins might generate de novo autoantigens that upon release contribute to the generation of autoantibodies and autoimmune diseases as PBC. Christoph Peter Berg and Gerburg Maria Stein contributed equally to this paper and share first authorship. Sebastian Wesselberg and Kirsten Lauber share equal senior authorship.     

Expression of three cross-reactive idiotypes on rheumatoid factor autoantibodies from patients with autoimmune diseases and seropositive adults

Approximately one-half of human monoclonal IgM anti-IgG autoantibodies (rheumatoid factors (RF] from unrelated individuals with cryoglobulinemia coordinately express three cross-reactive idiotypic antigens (CRI). The CRI are detected with: 1) monoclonal antibody 17.109, which recognizes a conformation-dependent CRI on K-light chains; and 2) two rabbit anti-peptide antibodies that react with primary sequence-dependent CRI (PSL2 and PSL3) corresponding to the conserved second and third K-chain complementarity-determining regions, respectively. In the present experiments, the structural features of polyclonal RF autoantibodies from diverse patients with rheumatoid arthritis and from those with primary Sj?gren's syndrome, and from seropositive elderly subjects without overt autoimmune diseases, were investigated with these three defined anti-CRI reagents. The pattern of expression of the CRI differed among patient groups. Only the RF autoantibodies from Sj?gren's syndrome patients frequently displayed all three CRI. However, the RF from nearly every subject tested, including patients with rheumatoid arthritis, were enriched in the primary sequence-dependent PSL2-CRI as compared to RF-depleted Ig from the same subjects. Amino acid sequence analysis of monoclonal IgM-RF indicates that PSL2-CRI-positive light chains probably represent the products of a single Vk gene. Therefore, a proportion of the polyclonal RF from different autoimmune states may represent somatic variants of this germ-line RF Vk gene which retain the PSL2 sequence as a common element.     

Natural thymocytotoxic autoantibodies in autoimmune and normal mice.

Natural thymocytotoxic autoantibodies (NTA) were found in all mouse strains. Among those strains that show autoimmune syndromes resembling human systemic lupus erythematosus (SLE), the NZB and NZBxNZW had high levels of NTA, the BXSB had moderate levels, and the MRL/1 and MRL/n had very low levels. In addition, some normal strains had high levels, sometimes even higher than the autoimmune strains. The NTA were mostly IgM and were present, but not concentrated, in the cryoprecipitates of teh autoimmune mouse strains. In most strains, they were directed toward an antigen shared by thymocytes and brain. The failure to find high levels of NTA in all autoimmune mouse strains, as well as the finding of very high levels in some normal strains, make it unlikely that such auto-antibodies are a fundametnal etiologic factor in all murine SLE.     

DNA content of Hurthle cell nodules in autoimmune thyroiditis

Hurthle cells are found in thyroid neoplasms and in reactive nodules in thyroiditis or goitrogenic processes. Cytometric studies have evaluated Hurthle cell neoplasms but not their reactive counterparts. DNA content of Hurthle cells in 22 cases of autoimmune thyroiditis was measured by flow cytometry and image content of Hurthle cells in 22 cases of autoimmune thyroiditis was measured by flow cytometry and image processing using nuclei extracted from paraffin-embedded tissue after microdissection of the Hurthle cell nodules. All 22 autoimmune thyroiditis Hurthle cell nodules were diploid, including 16 without associated neoplasms and six with associated malignant neoplasms (four papillary carcinomas, one follicular carcinoma and one follicular adenoma with papillary carcinoma). Concordance between flow cytometry and image processing was 100%. These findings indicate that the markedly atypical Hurthle cells in autoimmune thyroiditis are diploid by DNA quantitation. This suggests that atypia in Hurthle cells due to reactive or neoplastic processes may be differentiated by quantitative DNA analysis.     

Immunogenetic and ontogenetic studies of chickens with selective IgA deficiency and autoimmune thyroiditis

In addition to spontaneous hypothyroidism and autoimmune thyroiditis, chickens of the obese strain (OS) have a high incidence of selective IgA deficiency. Elevated levels of serum IgM also occur in many OS chickens. The IgA deficiency begins by 2 weeks, the age when hypothyroidism is developing. Like thyroiditis, a greater incidence of IgA deficiency was noted in OS birds homozygous for the B¹ allele than for the B⁴ allele of the major histocompatibility locus. Although IgA deficiency occurs in both sexes, it is found in a higher frequency in females than males (2:1). An abnormal ontogenesis of immunological competence may influence both traits.     

Experimental autoimmune thyroiditis in mice chronically treated from birth with anti-IgM antibodies

The role of T lymphocytes in the pathogenesis of experimental autoimmune thyroiditis in mice is well established while the role of B lymphocytes is unclear. Mice with thyroid lesions have thyroglobulin antibodies whereas these antibodies can occur in mice immunized with Tg that do not develop thyroid lesions. To determine whether thyroglobulin antibodies are necessary for the development of the thyroid infiltrates with mononuclear cells, which are characteristic for experimental autoimmune thyroiditis, AKR mice chronically treated from birth with goat anti-mouse IgM antibodies were immunized with mouse thyroglobulin in Freund's complete adjuvant when they were 7 weeks old. Control mice, similarly immunized, were chronically injected from birth with normal goat gamma-globulin. Three weeks after immunization, all mice were sacrificed, thyroglobulin antibodies in the serum were measured by hemagglutination assay and enzyme-linked immunosorbent assay, and thyroid pathology was assessed. The serum concentration of IgG and IgM, the percentage of B and T lymphocytes in the spleen (flow cytometry), and the in vitro proliferative response of spleen lymphocytes to stimulation by PHA, LPS, and Tg were also measured. All mice treated with anti-IgM antibodies did not have detectable thyroglobulin antibodies but 63% of these mice and 88% of control mice (all of which had thyroglobulin antibodies) had thyroid lesions. Mice treated with anti-IgM antibodies that did not have thyroid lesions had a more pronounced depression of B lymphocytes than similarly treated mice that had thyroid lesions. These experiments suggest that thyroglobulin antibodies are not necessary for the development of thyroid infiltrates with mononuclear cells. B lymphocytes could still participate in the production of experimental autoimmune thyroiditis by presenting thyroglobulin to helper T lymphocytes.