The role of the alternative pathway of complement activation in glomerular diseases.

The complement system (CS) has recently been recognized as a bridge between innate and adaptive immunity that constitutes a very complex mechanism controlling the clearance of pathogens, cellular debris, and immune complexes. Out of three known pathways of complement activation, the alternative pathway (AP) plays a critical role in host defense by amplifying the complement response, independently of initiation pathway and continuously maintaining low-level activity in a process called 'thick-over.' A key molecule of the CS is C3, in which the AP is constantly activated.

Association of Retinoid X Receptor Alpha Gene Polymorphism with Clinical Course of Chronic Glomerulonephritis.

BACKGROUND Vitamin D (VD), VD binding protein, VD receptor (VDR), and retinoids are involved in pathogenesis of chronic glomerulonephritis (ChGN). We aimed to compare distribution of VD pathway gene polymorphisms in ChGN patients showing glomerular filtration rate (GFR) category 1-3, GFR category 5D, and healthy controls in order to elucidate the role of VD-related polymorphisms in the course of ChGN. MATERIAL AND METHODS GFR category 1-3 ChGN patients (n=195), GFR category 5D ChGN patients (n=178), and controls (n=751) underwent testing for polymorphisms of genes encoding VD binding protein (GC, rs2298849, rs7041, rs1155563), VDR (VDR, rs2228570, rs1544410), and retinoid X receptor alpha (RXRA, rs10776909, rs10881578, rs749759).

Do circulating antibodies against C1q reflect the activity of lupus nephritis?

Introduction: The results of recent studies suggest that there is a link between the presence of antibodies against C1q (anti-C1q Abs) and kidney involvement in systemic lupus erythematosus (SLE). However, it remains unclear whether the clinical symptoms of lupus nephritis (LN) may be associated with the presence of anti-C1q Abs in serum.

Objectives: The aim of the study was to compare the prevalence and levels of anti-C1q Abs and antibodies against double-stranded DNA (anti-dsDNA Abs), circulating immune complexes binding C1q (CIC-C1q), as well as complement components C3 and C4 in the sera of patients with LN in relation to the clinical activity of SLE and symptoms of LN.