Interactions of Lymphocytes, Thyrocytes and Fibroblasts in Hashimoto’s Thyroiditis: An Immunohistochemical and Ultrastructural Study

Abstract

Background: The mechanism of autoimmune reaction, a diffuse process consisting of a combination of epithelial cell destruction, lymphoid cellular infiltration, and fibrosis in Hashimoto’s thyroiditis, is not well known. The aim of this study was to analyse the cell subsets in thyroid tissue of patients with Hashimoto’s thyroiditis. Methods: We studied paraffin-embedded thyroid specimens obtained from children with Hashimoto’s thyroiditis and children without an autoimmune thyroid disease. Mononuclear T cells were detected by means of CD3+, CD4+, CD8+ antibodies, B cells by CD79 alpha+ antibodies, and antigen-presenting cells by CD1a+ antibodies, and they were counted in every 1,000 cells. The specimens from each patient were routinely estimated and investigated under the electron microscope. Results: In Hashimoto’s thyroiditis, we observed a statistically significant increase in T suppressor/cytotoxic cells CD8+ (20.54 ± 0.68%) in comparison to the control group (0.65 ± 0.30%), simple goitre (4.01 ± 5.54%) and nodular goitre (8.53 ± 2.37%), and a statistically significant increase in plasma CD79 alpha+ cells (31.65 ± 9.11%) in comparison to the control group (4.11 ± 1.94%), simple goitre (1.83 ± 0.64%) and nodular goitre (5.22 ± 1.63%). Simultaneously, we observed a low number of CD4+ T helper cells in the thyroid gland (0.93 ± 0.99%) in Hashimoto’s thyroiditis (0.19 ± 0.05% in the control group, 1.05 ± 2.71% in simple goitre, 2.03 ± 1.06% in nodular goitre). The ultrastructural investigations showed interactions between T cells, plasmocytes, fibrocytes and thyrocytes leading to apoptosis of thyrocytes. An immunological synapse between T cells, plasmocytes and thyrocytes in the thyroid gland was noticed. Conclusions: In Hashimoto’s thyroiditis, autoantigen presentation in combination with a low number of CD4+ T helper cells and a high number of CD8+ cells and plasmocytes caused the development of a cytotoxic reaction against thyrocytes, leading to apoptosis of the thyrocytes.

Characterization of subepithelial interstitial cells in normal and pathological human prostate

“…), as they comprised point‐to‐point contacts between cell membranes, without the underlying cell structures that are observed in the other types of junctions. The ultrastructure of these contacts was comparable with that of immunological synapses (between immunological cells and other cell types), and to our knowledge such contacts formed by tumour cells have not been reported previously. Many studies have reported on the potential of stromal cells to induce tumour growth in PCa .…”

Lower CD28+ T cell proportions were associated with CMV-seropositivity in patients with Hashimoto’s thyroiditis

“…Our results demonstrated a significant increase of CD28-negative T cells in HT patients, associated with CMV-seropositivity within the CD8+ T cell subpopulation. A role of CD8+ T cells in thyroid inflammation, particularly in HT, was also clearly shown by others [15,26-28]. Our results on CD28 expression differ from a study in 35 children with autoimmune thyroiditis in whom baseline CD28 expression was similar to healthy controls [29].…”

Serum cystatin C is closely associated with euthyroid Hashimoto’s thyroiditis in adult female Chinese patients

“… 1 The main features of Hashimoto’s thyroiditis include increased serum thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TGAb), and infiltration of lymphocytes and plasma cells into the thyroid. 2 – 5 In urban areas of China, the prevalence of TPOAb positive and TGAb positive were 11.5% and 12.6%, respectively. 6 Hashimoto’s thyroiditis can also cause primary hypothyroidism, thyroid cancer, atherosclerosis, diabetes, and adverse pregnancy outcomes.…”