Serum levels of soluble forms of T cell activation antigens CD27 and CD25 in systemic lupus erythematosus in relation with lymphocytes count and disease course

Abstract

SummarySystemic lupus erythematosus (SLE) patients are characterized by a low lymphocyte count, which is considered a specific disease marker and is related to disease activity. The membrane bound molecules CD25 and CD27 are expressed and released in a soluble CD25 (sCD25) and soluble CD27 (sCD27) form by activation of predominantly T cells. In previous studies it was claimed that sCD25 as well sCD27 might be used as parameters for activation of the immune system; a correlation between the sCD25 profile with the disease course in SLE patients was also shown. To assess the relationship between lymphocyte count and these T cell activation markers, we performed a cross-sectional and a longitudinal study. In the longitudinal study three SLE patients who were known for a long time at our outpatient clinic were studied. Both T cell markers strongly correlated with each other and formed a reflection of the disease course. In all 7 periods of exacerbation, which we observed in the 3 investigated patients, both levels increased preceding this period; however, no correlation was found with the lymphocyte count. In the cross sectional study of 69 patients with SLE, sCD25 and sCD27 levels were correlated with defined disease manifestations; sCD25 was elevated in all periods of increased disease activity. The same holds true for sCD27, with the exception of patients with nephritis in which the highest levels were observed. Both profiles of sCD25 and sCD27 were strongly correlated during the whole disease course. Our data prove that in the pathogenesis of SLE an active recruitement of unprimed and primed T cells takes place.

The soluble CD40 ligand sCD154 in systemic lupus erythematosus

“…This protein is expressed transiently by activated CD4 + T cells (30,(35)(36)(37). However, CD154 also can be cleaved from the cell surface of activated T cells, releasing an sCD154 of approximately [18][19][20]. This sCD154 can apparently form homotrimers that can induce B-cell activation or differentiation (33,38).…”

“…On the other hand, soluble proteins released from activated T cells may contribute to immune activation (20)(21)(22)(23). TNF-α, for example, is a protein that can exist as either a soluble molecule or a membrane-associated glycoprotein (24)(25)(26).…”

Biomarkers in systemic lupus erythematosus

“…The increase in sIL-2R levels was most pronounced with major flares, especially in nephritis [39,[42][43][44] and rises in sIL-2R levels preceded flares [40,41]. These results suggest that sIL-2R can be considered as a promising candidate biomarker of activity in patients with SLE, especially among those with kidney involvement.…”

“…Several studies demonstrated an increase of sIL-2R levels during flares and a decrease with treatment and clinical improvement [33,[39][40][41][42][43]. The increase in sIL-2R levels was most pronounced with major flares, especially in nephritis [39,[42][43][44] and rises in sIL-2R levels preceded flares [40,41].…”

Increase of activated T-cells and up-regulation of Smad7 without elevation of TGF-beta expression in tonsils from patients with pustulosis palmaris et plantaris

“…In peripheral blood of systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) patients, hyper activation of T-cells has been found [9,10], and this activation was correlated with their clinical course [11,12]. Moreover, activated T-cells reportedly take important part in pathogenesis of SLE by coordinating production of autoantibody with B-cell [13] and in RA by leading to chronic inflammation in synovial joint [14].…”