Enhanced hyaluronan synthesis in the MRL-Fas(lpr) kidney: role of cytokines.

Background/aim: Pathological accumulation of the extracellular matrix component hyaluronan (HA) occurs in the kidney cortex in immune-system mediated tissue injury. The purpose of the present study was to examine the pattern of HA deposition and the mechanisms of HA synthesis in the MRL-Fas(lpr) mouse model of lupus nephritis.

Methods: Kidneys from normal and autoimmune mice were examined for HA content by immunofluorescence staining.

Expression profile of hyaluronidase mRNA transcripts in the kidney and in renal cells.

The accumulation of hyaluronan (HA) in the renal cortex is a characteristic feature of inflammatory renal diseases. Fragments of HA derived from high molecular weight precursors are known to display inflammatory effects in vitro and could, therefore, participate in immune renal injury. To understand the mechanisms of HA fragmentation in vivo we examined the expression of recently characterized mammalian hyaluronidases in normal and autoimmune kidneys and in cell lines.

Characteristic matrix and tubular basement membrane abnormalities in the CBA/Ca-kdkd mouse model of hereditary tubulointerstitial disease.

CBA/CaH-kdkd mice develop hereditary tubulointerstitial disease with mononuclear cell infiltration and cyst formation, possibly representing a model of human nephronophthisis. The purpose of the present investigation was to examine the components of the fibrotic changes which typically develop in the kidneys of these mice. By conventional histology, kdkd mice displayed progressive interstitial fibroblast and matrix accumulation.