Kunio Yamaoka

Possible involvement of Epstein-Barr virus (EBV) in polyclonal B-cell activation in Sjögren's syndrome

The following results suggest that EBV might be involved in the mechanism of polyclonal B-cell activation of Sjögrens syndrome (SS). (1) The levels of serum anti-VCA antibodies of both IgG and IgM class were significantly elevated in SS. (2) Excretion of EBV from the oropharynx was frequently observed in SS. (3) Spontaneously transformed B-cell lines producing a large amount of transforming EBV were established preferentially from SS. (4) An EBV-specific regulatory mechanism was impaired in SS.

Induction of FcεRII/CD23 on human T cells by excretory and secretory antigen of dirofilaria immitis

We investigated the capacity of excretory and secretory antigen (ES) derived from living filarial worms in the induction of CD23 expression on human peripheral blood T cells by using flow cytometry. ES (10 μg/ml) significantly induced the expression of CD23 on human T cells. Moreover, increased CD23 expression was completely abolished by preincubation with specific antibody to ES. The results suggest that ES might play a certain role in IgE antibody production by induction of CD23 expression on T cells.

Discordant Interleukin 2 Production in Monozygotic Twins Concordant for Systemic Lupus Erythematosus

We present data from monozygotic twins concordant for SLE. IL-2 production by peripheral blood mononuclear cells from the patients, when they were discordant for SLE activity, were measured employing cellular mixing experiments. Macrophages from active SLE had a suppressive effect on IL-2 production. Furthermore, SLE T cells appeared to have a defect in IL-2 production irrespective of disease activity. These defects might play an important role in the disordered immunoregulation in SLE.