In IgA nephropathy, abnormal O-glycosylation of IgA1 molecules contributes to mesangial IgA1 deposition and the development of glomerular injury; however, direct in situ demonstration of aberrantly O-glycosylated IgA1 within glomerular immune deposits has not been reported. This study investigated the presence of abnormally glycosylated IgA1 in situ and its spatial relationship with complement within the immune deposits and correlated these features with glomerular lesion severity. Immunofluorescence and confocal microscopy were used to evaluate 19 consecutive renal biopsies, and the severity of glomerular lesions were also scored. Aberrantly glycosylated IgA was observed within the immune deposits, and its amount was found to correlate with both the severity of glomerular lesions and the amount of C3c on the surface of the deposits. These results demonstrate that qualitative and quantitative evaluation of aberrantly glycosylated IgA can be performed on routine renal biopsy samples. Its presence in immune deposits likely influences the spatial organization of IgA and C3c, thereby contributing to the glomerular inflammatory response in IgA nephropathy.
Aberrantly glycosylated IgA1 in glomerular immune deposits of IgA nephropathy / Giannakakis, Konstantinos; S., Feriozzi; M., Perez; FARAGGIANA DI SARZANA, Tullio; A. O., Muda. - In: JOURNAL OF THE AMERICAN SOCIETY OF NEPHROLOGY. - ISSN 1046-6673. - 18:12(2007), pp. 3139-3146. (Intervento presentato al convegno 43rd Annual Congress of the European-Renal-Association/European-Dialysis-and-Transplant-Association (ERA-EDTA) tenutosi a Glasgow, SCOTLAND nel JUL 15-18, 2006) [10.1681/asn.2007030259].
Aberrantly glycosylated IgA1 in glomerular immune deposits of IgA nephropathy
GIANNAKAKIS, Konstantinos;FARAGGIANA DI SARZANA, Tullio;
2007
Abstract
In IgA nephropathy, abnormal O-glycosylation of IgA1 molecules contributes to mesangial IgA1 deposition and the development of glomerular injury; however, direct in situ demonstration of aberrantly O-glycosylated IgA1 within glomerular immune deposits has not been reported. This study investigated the presence of abnormally glycosylated IgA1 in situ and its spatial relationship with complement within the immune deposits and correlated these features with glomerular lesion severity. Immunofluorescence and confocal microscopy were used to evaluate 19 consecutive renal biopsies, and the severity of glomerular lesions were also scored. Aberrantly glycosylated IgA was observed within the immune deposits, and its amount was found to correlate with both the severity of glomerular lesions and the amount of C3c on the surface of the deposits. These results demonstrate that qualitative and quantitative evaluation of aberrantly glycosylated IgA can be performed on routine renal biopsy samples. Its presence in immune deposits likely influences the spatial organization of IgA and C3c, thereby contributing to the glomerular inflammatory response in IgA nephropathy.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.