ANALYSIS OF IGA FROM IGA-FIBRONECTIN COMPLEX IN THE PATIENT WITH IGA NEPHROPATHY AND ITS EFFECT ON THE FUNCTION OF RENAL CELIS IN CULTURE.

IgA-fibronectin complex(IgA- f / C) have been in the serum of patients with IgA nephropathy(IgAN) with IgA nephropathyhigher incidence than其他serological markers for IgAN.The purpose of this study is；1. to determine the incidence of IgA-F in pediatric patiens with IgAN in addition to looking atthe basis of this assay system using collagen type I -coated microtiter plate2. to analyze the formation of this complex in patients，Western blot utilizing a set of monoclonal anti-human fibronectin antibodies for materials fromheparin-affinity column treated by patient's serum.Result：1. Significant detection of IgAN patients was observed in IgAN 52%，Elevated IgA-F / C which not correlate with severity of disease or an attack of gross hematuria与Henoch-Schonlein purpura nephritis和active stage of some of patients with Henoch-Schonlein purpura nephritis and active stage ofrheumatoid arthritis. A few of definite IgAN patient with low activity of IgA-F / C turnedout to be significant by treatment with gelatin-column.2. Silver-staining of sd - page for eluate ofgelatin-,or heparin-column showed that binding proteins of serum to each column contained proteins ofwide-ranged分量，and some of them demonstrated only in patients but not controls. The extra-proteins was shownespecially in the material from heparin-affinity column.这些findings were confirmed by Westernblot procedure, suggesting that serum fibronectin was degraded，它必须在一个established protocol for isolation of fibronectin. Reactivity of somemonoclonal antibodies to degraded fibronectins was specific to patient.3. Application of purifiedIgA onto immobilized fibronectin fragments from patient and cathepsin D-digested fibronectindemonstrated that 42 kilodalton fragment, produced both by patient and cathepsin D proteolyis，was bound to IgA.These findings may have ramifications in the origin and possible pathogeneticimportance for the etiology of IgAN。

IgA-fibronectin complex(IgA-F・C) have been in the serum of patients with IgA nephropathy(IgAN) with higher incidence than other serological markers for IgAN.The purpose of this study is ; 1. to determine the incidence of IgA-F・C in pediatric patiens with IgAN in addition to looking at the basis of this assay system using collagen type I -coated microtiter plate, and 2. to analyze the formation of this complex in patients, with Western blot utilizing a set of monoclonal anti-human fibronectin antibodies for materials from heparin-affinity column treated by patient's serum.Result : 1. Significant detection of IgA-F・C in IgAN patients was observed in 52%, which did not correlate with severity of disease or an attack of gross hematuria. Elevated IgA-F・C was also detected in some of patients with Henoch-Schonlein purpura nephritis and active stage of juvenile rheumatoid arthritis. A few of definite IgAN patient with low activity of IgA-F・C turned out to be significant by treatment with gelatin-column.2. Silver-staining of SDS-PAGE for eluate of gelatin-, or heparin-column showed that binding proteins of serum to each column contained proteins of wide-ranged molecular weight, and some of them demonstrated only in patients but not controls. The extra-proteins was shown especially in the material from heparin-affinity column. These findings were confirmed by Western blot procedure, suggesting that serum fibronectin was degraded, which must be neglected in a established protocol for isolation of fibronectin. Reactivity of some monoclonal antibodies to degraded fibronectins was specific to patient.3. Application of purified IgA onto immobilized fibronectin fragments from patient and cathepsin D-digested fibronectin demonstrated that 42 kilodalton fragment, produced both by patient and cathepsin D proteolyis, was bound to IgA.These findings may have ramifications in the origin and possible pathogenetic importance for the etiology of IgAN.