Detection of serum antibodies to retroviral proteins in patients with primary sjögren's syndrome (autoimmune exocrinopathy)

Abstract

Primary Sjögren's syndrome (SS) is considered a benign autoimmune disease; it is characterized by lymphoid infiltration of salivary and lacrimal glands, often accompanied by the presence of serum autoantibodies, particularly anti‐Ro (SS‐A) and anti‐La (SS‐B). There are important immunologic similarities between primary SS and acquired immunodeficiency syndrome. To investigate for a possible immune response to retroviral proteins in primary SS, we performed immunoblotting against human immunodeficiency virus‐1 (HIV‐1) proteins using sera from 47 patients with primary SS. Moderate‐to‐strong reactivity, suggesting the presence of serum antibodies, was found in 14 patients (30%). Of 120 normal subjects, only 1 showed moderate positivity. All 14 positive SS sera reacted against p24 (gag) but failed to react against gp41 or gp120 (env). This response did not reflect hypergammaglobulinemia since immunoglobulin concentrations among the 29 SS patients studied were the same in sera that contained and sera that did not contain anti‐gag reactivity. Two sera also reacted against p17 gag. Four reacted against HIV‐2 core proteins, but none reacted with core proteins of human T lymphotropic virus‐I. Only 1 of the 14 sera reacted against Ro (SS‐A), and 1 other reacted against La (SS‐B). These results identify a subset of SS patients characterized by 1) the presence of serum antibodies to HIV‐1 group‐specific, but not type‐specific, proteins, and 2) the relative absence of anti‐Ro (SS‐A) and anti‐La (SS‐B) autoantibodies. In this latter respect, these SS patients constitute a subpopulation that resembles patients with HIV‐induced SS‐like disease.

Sicca syndrome associated with hepatitis C virus infection

“…Other viruses have a salivary gland tropism: HCV, Epstein-Barr virus, and human T lymphotropic virus type I (HTLV-I) genes have been found in this tissue (28)(29)(30)(31). Moreover, a possible retroviral etiology of Sjogren's syndrome was suggested by the presence of antibodies against the retroviral protein p24 in 30% of the patients studied (32). These antibodies may be induced by an endogenic retroviral antigen (HRES) which cross-reacts with the HTLV-I p24 protein.…”

Restricted junctional usage of T cell receptor Vβ2 and Vβ13 genes, which are overrepresented on infiltrating T cells in the lips of patients with sjögren's syndrome

“…Self antigens have not been identified in SS; however, observations suggest the possibility of a retroviral etiology for the disease (10)(11)(12). Approximately 30% of patients with primary SS have serum antibodies that react with the major capsid protein of human immunodeficiency virus type 1 (HIV-l) (10).…”

B cell clonality in gastric lymphoid tissues of patients with Sjogren's syndrome.

“…Samples from each specimen were mounted on slides and stained with haematoxylin-eosin and with a modified Giemsa stain to study the degree of inflammation and the presence of lymphoid follicles and H pyloni. The lymphoid component was graded on a scale of 0 (scattered plasma cells in lamina propria without lymphoid follicles) to 5 (diffuse infiltration-prominent lymphoepithelial lesions) (figure) according to the system proposed by Wotherspoon et al 4 A lymphoid follicle was defined as such when an unequivocal germinal centre was seen. Immunophenotype data of the lymphoid population were collected for B (CD20-L26-DAKO), T (CD3-T cell-DAKO), and K/A chain (DAKO) restriction.…”