The Relationship Of Osteopontin, CD68, Clinical Indicators And Renal Interstitial Injury In IGA Nephropathy

Objective:To investigate the expression of osteopontin,CD68 in IgA nephropathy and the relationship of osteopontin,CD68 ,the clinical indicators and renal interstitial injury.Methods:According to biopsy results,renal biopsy specimens from 26 patients diagnosed primary IgA nephropathy(except lupus nephritis, HBV-associated nephropathy, purpura nephritis, etc.) were selected as experimental group. According to Lee's method ,the pathology of the renal were divided intoⅠ～Ⅴgrade .The renal interstitial injury were divided into 0～3 levels.And the blood pressure,24-hour urinary protein,serum creatinine, creatinine clearance rate were collected. The other four normal renal tissue taken from trauma patients or renal tumors were as control group.The expression of osteopontin and CD68 in renal tissue was investigated by immunohistochemistry.The expression of osteopontin mRNA was investigated by RT-PCR. Results:Up to 86% patients with IgA nephropathy had renal interstitial injury. Renal interstitial injury was positively correlated with serum creatinine, hypertension, and was negative correlated with creatinine clearance rate. 24-hour urinary protein was positively correlated with serum creatinine and renal interstitial damage.The CD68-positive cells in glomeruli and renal interstitial of IgA nephropathy(0 grade tubulointerstitial damage,LeeⅠ～Ⅱ)was higher than normal control group,but no significant difference was found. The CD68-positive cells of IgA nephropathy (LeeⅢ～Ⅴ)was significantly higher than the control group. The expression of CD68 in renal interstitial was positively correlated with 24-hour urine protein in IgA nephropathy which tubulointerstitial damage was grade 1～3 .Compared with normal control group, the expression of OPN protein and OPN mRNA were significantly increased in IgA nephropathy group.The expression of OPN,OPN mRNA were not correlated with renal interstitial injury and 24-hour urine protein.The expression of CD68 in renal interstitial was positive correlated with renal interstitial injury .The expression of CD68 and OPN was positively correlatedConclusions:(1)Proteinuria as an important factor was involved in tubulointerstitial damage of IgA nephropathy.It was one of the main factors leading to the deterioration of IgA nephropathy.(2) Osteopontin and monocyte/macrophage infiltration was involved in proteinuria in IgA nephropathy.(3)Monocyte/macrophage infiltration in IgA nephropathy was involved in renal interstitial injury.Osteopontin was associated with inflammation, it is participate in renal interstitial injury by mediating mononuclear and macrophages.