Expression of very late antigen-4 and lymphocyte function-associated antigen-1 on peripheral blood lymphocytes from patients with graves disease

Role of Viruses in the Pathogenesis of Multiple Sclerosis

Multiple sclerosis (MS) is an immune inflammatory disease, where the underlying etiological cause remains elusive. Multiple triggering factors have been suggested, including environmental, genetic and gender components. However, underlying infectious triggers to the disease are also suspected. There is an increasing abundance of evidence supporting a viral etiology to MS, including the efficacy of interferon therapy and over-detection of viral antibodies and nucleic acids when compared with healthy patients. Several viruses have been proposed as potential triggering agents, including Epstein-Barr virus, human herpesvirus 6, varicella-zoster virus, cytomegalovirus, John Cunningham virus and human endogenous retroviruses. These viruses are all near ubiquitous and have a high prevalence in adult populations (or in the case of the retroviruses are actually part of the genome). They can establish lifelong infections with periods of reactivation, which may be linked to the relapsing nature of MS. In this review, the evidence for a role for viral infection in MS will be discussed with an emphasis on immune system activation related to MS disease pathogenesis.

Lymphocytes in peripheral blood and thyroid tissue in children with Graves' disease

BACKGROUND

This study was undertaken to analyze subsets of lymphocytes in peripheral blood in the early phase and in the thyroid tissue in the late phase of Graves' disease (GD) in children.

METHODS

The study included 30 children with GD and 30 healthy children. Monoclonal antibodies were used to define peripheral blood lymphocyte subsets and they were analyzed using the flow cytometer Ortho Diagnostic System. After thyroidectomy, T cells were detected by CD3, CD4, CD8 antibodies, B cells by CD79alpha antibodies, and the antigen presenting dendritic cells (APCs) by CD1alpha antibodies (DakoCytomation) in the thyroid tissue.

RESULTS

Before the treatment, an increased percentage of CD4+ T helper cells and B cells and decreased CD8+ T suppressor/cytotoxic cells were observed in peripheral blood in all the GD children. The number of lymphocytes and dendritic cells in the thyroid tissue increased in the children with GD in comparison to the control group, especially T cells subsets CD4+ and CD8+ and CD79alpha+ B cells. The percentage of T cells in the thyroid tissue was lower and that of B cells was higher than in peripheral blood. In their structure, thyrocytes can have components similar to alpha-chains connected with beta-microglobulins, which were characteristic for APCs.

CONCLUSIONS

The primary defect of immunoregulation in children with GD is probably dependent on a large number and the activity of T helper cells and on a small number and hypofunction of T suppressor cells. The amount of lymphocytes decreased proportionally to the duration of methimazole treatment. The thyrocytes probably can present antigens.

L-selectin gene polymorphisms in Graves' disease

OBJECTIVE

Graves' disease (GD) is an autoimmune disorder with genetic predisposition. There is strong evidence that members of the selectin family participate in the interaction between leucocytes and the endothelium, as well as in inflammatory cell recruitment. Moreover, a high serum level of a soluble form of L-selectin (SL-selectin) has been reported in untreated GD patients. However, the impact of L-selectin polymorphisms on GD has not yet been investigated. The aim of the present study was to elucidate whether L-selectin gene polymorphisms were associated with the development of GD.

SUBJECTS AND DESIGN

L-selectin gene polymorphisms were investigated in 230 Chinese GD patients and 208 healthy control subjects without antithyroid autoantibodies or a family history of autoimmune disorders. Two L-selectin SNPs were genotyped by the PCR-restriction fragment length polymorphism (PCR-RFLP) method.

RESULTS

A C/T polymorphism at position -642 of the promoter region and a Pro213Ser (c.725 C-T) polymorphism in exon 6 were examined using PCR-RFLP. There was a significant increase in -642T allele frequency in GD patients compared with healthy controls (70 vs. 62%; P = 0.0126; P(c) = 0.0252). The frequency of the c.725C allele in exon 6 also appeared higher in GD patients than in controls. Haplotype analysis showed a significant decrease in the -642C/c.725T haplotype in GD patients (26 vs. 34%; P = 0.0095; Pc = 0.0190). However there was no association between polymorphisms and certain GD clinical phenotypes, including age of onset and ophthalmopathy.

CONCLUSIONS

L-selectin gene polymorphisms are associated with GD susceptibility in Chinese patients.