| Resum: |
The complement system (CS) is a key component of innate immunity that culminates in the formation of the membrane attack complex (MAC or C5b9) on the membranes of pathogens or apoptotic cells, and its activation can occur through three pathways: the classical, the lectin, and the alternative pathways, where the first two are mainly triggered by the recognition of microorganisms or immune complexes, while the alternative pathway is constitutively activated through spontaneous hydrolysis of C3, and although this process is physiologically regulated by complement inhibitors, in certain kidney diseases such as atypical hemolytic uremic syndrome, this pathway can be overactivated, and overactivation of the CS has also been described in other complex glomerulopathies, although there are currently no reliable methods to assess its contribution in these diseases, so the objective of this study was to evaluate the utility of the ex vivo C5b9 deposits test on human endothelial cells (HMEC-1) as a tool to detect complement activation in complex glomerulopathies, and serum samples from patients with lupus nephritis (LN), membranous glomerulopathy (MG), and IgA nephropathy (IgAN) were analyzed, where in LN, C5b9 deposits were associated with higher lupus activity assessed by the SLEDAI index, and in MG, no clear correlation was found with clinical parameters although there was a slight association with renal function deterioration, while in IgAN, deposits were linked to greater histological damage according to the MEST-C score of the Oxford classification found in kidney biopsies, and although serum levels of C3 and C4 were measured, no consistent correlations were observed, suggesting these do not reliably reflect CS activity, so in conclusion, the ex vivo C5b-9 deposits test could represent a useful complementary diagnostic tool in the assessment of the complement system in complex glomerulopathies when traditional serum markers are inconclusive. |
visitant ::
identificació
dir. (Hospital Universitari Vall d'Hebron)
