T and B Cells in Graves' Orbitopathy

NCT ID: NCT03195296

Last Updated: 2018-02-12

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 20 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2017-01-01
• Study Completion Date: 2017-05-31

Brief Summary

Graves orbitopathy (GO) is an inflammatory eye disease associated in 95% of patients with Graves' hyperthyroidism (GH), in ~3-4% with hypothyroid autoimmune thyroiditis, and in ~1-2% with thyroid autoimmunity in the absence of thyroid dysfunction, the former known as euthyroid GO. The pathogenesis of GO is autoimmune, with the TSH-receptor being considered the major autoantigen, thereby establishing a pathogenetic link between the thyroid and orbital tissue. Thus, TSH-receptor is expressed by orbital fibroblasts, where it forms a complex with the IGF-1 receptor. Unlike GH, which is notoriously caused by TSH-receptor stimulating autoantibodies, GO is believed to reflect cell-mediated autoimmunity, as suggested by studies showing a Th1-like pattern of cytokine release by primary cultures of orbital infiltrating lymphocytes from GO patients. On the other hand, a role of B lymphocytes has emerged in recent years based on the observation that the anti-CD20 monoclonal antibody rituximab has a beneficial effect on GO activity, as demonstrated by a recent randomized clinical trial in which rituximab was compared with intravenous glucocorticoids (GC), being the former the standard treatment of moderately-severe GO. The explanation for the findings was that B lymphocytes are involved in the pathogenesis of GO as antigen-presenting cells. However, in spite of the above mentioned promising observations, another randomized clinical trial in which rituximab was compared with placebo provided opposite results. Thus, rituximab had no effect at all on GO. Data from the two studies were confronted and major differences between the two cohorts emerged, especially concerning GO activity, leading to the conclusion that rituximab may be effective for active, but not for inactive GO. Rituximab has been employed also for autoimmune diseases other than GO, including type 1 diabetes. In the former, it was shown that the effectiveness of rituximab paralleled the presence of CD20-positive infiltrating lymphocytes in pancreas islets. We therefore postulated that something similar may occur in GO, because of which we planned the present, perspective, observational study, aimed at determining the presence and immunohistochemical features of lymphocytes infiltrating orbital tissues in patients with GO and to relate them with the clinical features of GO.

Conditions

Graves Ophthalmopathy

Study Design

• Observational Model Type: CASE_ONLY
• Study Time Perspective: PROSPECTIVE

Study Groups

Graves' Orbitopathy

Patients with Graves' Orbitopathy subjected to orbital decompression

No intervention

Intervention Type: OTHER

No intervention related to the study is foreseen

Interventions

No intervention

No intervention related to the study is foreseen

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Patients with Graves' orbitopathy subjected to orbital decompression

Exclusion Criteria

• None

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 80 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

University of Pisa

OTHER

Sponsor Role: lead

Responsible Party

Marinò Michele

Ricercatore (Assistant Professor)

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Michele Marinò, MD

Role: PRINCIPAL_INVESTIGATOR

University of Pisa

Other Identifiers

LYMPHGO

Identifier Type: -

Identifier Source: org_study_id