Effects of cyclosporine A on serum and urinary soluble interleukin-2 receptor in patients with lupus nephritis.
OBJECTIVE
To evaluate the association of the level of urine and serum soluble interleukin-2 receptor (sIL-2R) with disease activity and response to cyclosporine A (CsA) therapy in patients with lupus nephritis (LN).


METHODS
Sixteen hospitalized patients with LN were studied. At admission, fifteen patients had type IV-LN and one had type V-LN. All patients received CsA 6 mg/kg per day for 6-8 weeks, then tapered off gradually to 2 mg/kg per day. The levels of urinary and serum sIL-2R were determined by enzyme-linked immunosorbent assay (ELISA). Serum antinuclear antibody (ANA), anti-dsDNA antibody (A-ds-DNA), complement C3 and C4, total IgG, creatinine, urinary red blood cells and protein excretion, and lymphocyte subpopulations in the peripheral blood were also measured before and after CsA treatment.


RESULTS
In LN patients, both urinary (534 +/- 101 U/ml) and serum SIL-2R levels (326 +/- 148 U/ml) were higher than those in normal controls. These findings were associated with higher levels of peripheral blood CD4 + and CD8 + lymphocytes (29.3 +/- 4.24 and 28.6 +/- 9.12%), higher titer of serum anti-ds-DNA, lower levels of serum complement C2 and C4 (0.98 +/- 0.23 and 0.24 +/- 0.12 g/L), as well as more proteinuria (Upro 2.99 +/- 0.76 g/24 hrs) and hematuria (URBC 83.9 +/- 95.2 10(4)/ml). These abnormalities were gradually ameliorated by CSA therapy. The changes in the levels of both serum (116 +/- 58.6 U/ml) and urine (136 +/- 43.2 U/ml) SIL-2R induced by CsA (at 8 weeks) were correlated with the changes in the levels of CD4 + and CD8 + cells (23.2 +/- 3.30 and 26.7 +/- 3.54%), degrees of immune abnormalities (serum C3 and C4 1.28 +/- 0.14 and 0.42 +/- 0.06 g/L), and renal injuries (Upro 1.07 +/- 0.46 g/24 hrs, URBC 5.82 +/- 3.15 10(4)/ml).


CONCLUSIONS
These results suggest that serum and urinary sIL-2R are sensitive markers for the disease activity in patients with LN. CsA, a powerful immunosuppressive agent, significantly improves both immunologic disorders and renal functional impairments, the mechanism of which on patients with LN appears to inhibit the lymphocyte activation in the peripheral blood and renal tissues as indicated by the decrease in sIL-2R levels.
Tang
Z
Z
Department of Nephrology, Jingling Hospital, School of Medicine, Nanjing University, China.
Zhang
J
J
Zhang
S
S
Li
L
L
D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000032:analysis; D016572:Cyclosporine / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D008181:Lupus Nephritis / Q000188:drug therapy* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D015375:Receptors, Interleukin-2 / Q000378:metabolism*
D015415:Biomarkers; D007166:Immunosuppressive Agents; D015375:Receptors, Interleukin-2; D016572:Cyclosporine