PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Complement C3 Nephritic Factor”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources
PubMed1979

Mesangial glomerulonephropathy with deposition of IgG, IgM, and C3 induced by mercuric chloride: a new model.

A mesangial glomerulonephropathy, characterized by the deposition of rat IgG, IgM, and C3 in the glomerular mesangium, was produced in Wistar rats by a prolonged administration of mercuric chloride (HgCl2). The HgCl2 was dissolved in sterile distilled water (0.2 mg. per ml.), and a group of 15 male Wistar rats was given injections subcutaneously three times a week on alternate days at a dosage of 0.15 mg. per 100 gm. of body weight for 27 weeks. A control group of nine rats was given injections of distilled water only. Mesangial glomerulonephropathy developed in 12 of 15 rats injected with HgCl2 and was characterized by the following: (1) coarse granular and nodular deposition of rat IgG, IgM, and C3 in the mesangium of all glomeruli, (2) absence of staining for rat albumin, IgA, and fibrin, (3) presence of electron-dense deposits in the mesangium, (4) focal and segmental proliferation of the mesangial matrix, (5) interstitial inflammation, (6) tubular atrophy, and (7) deposition of periodic acid-Schiff-positive material in the medulla adjacent to the thin limbs of the loops of Henle. Glycosuria and a slight increase in proteinuria were observed transiently in some rats. The blood urea nitrogen levels were normal in all rats. Eluates from the kidneys with heavy mesangial deposits contained rat IgG. However, the eluted antibody failed to react with normal rat kidney tissue components. None of the above findings were present in the control rats. The study provides a model of a mesangial nephropathy that seems to be immunologically induced; however, the mechanism for the formation and deposition of the immune deposits containing rat IgG, IgM, and C3, and the nature of the antigen(s) have not been elucidated.

Animals↗
PubMedDate not supplied

[Complement].

Explore the source record for details and available documents.

Blood Coagulation↗
PubMed1979

Activation of the classical pathway of complement by the C3NeF-stabilized cell-bound amplification convertase.

C3 nephritic factor (C3NeF) has been shown to be composed of two heavy and two light chains, like IgG; in addition it shares antigenic determinants with IgG. C3NeF, purified from the sera of eight patients by incorporation of C3NeF into the stabilized fluid phase amplification C3 convertase, C3bBb(C3NeF), followed by its release after decay of convertase function, was investigated for its ability to bind 125I-C1q and to activate 125I-C1. It was found that although fluid phase C3b,Bb(C3NeF) is fully capable of binding 125I-C1q, it is not able to activate 125I-C1 even at concentrations of 1.3 x 10(12) C3bBb(C3NeF) complexs/ml. On the other hand, cell-bound C3bBb(C3NeF) is capable of both binding 125I-C1q and activating 125I-C1. This discrepancy between fluid phase and cell-bound, C3bBb(C3NeF) was found for C3NeF preparations from eight different patients and therefore seems to apply to all C3NeF preparations.

Binding Sites↗
PubMed1979

Further evidence for the antibody nature of C3 nephritic factor (C3NeF).

C3 nephritic factor (C3NeF), found in the sera of some patients with membranoproliferative glomerulonephritis, has been shown to be composed of two heavy and two light chains, like IgG; in addition it shares antigenic determinants with IgG. Purified C3NeF binds to the amplification convertase of complement, C3b,Bb, and thereby prevents decay of its C3-cleaving potential. The capability of C3NeF to bind to C3b,Bb was used as a means for purifying C3NeF to homogeneity. The investigation described in this report suggests that binding of C3NeF to C3b,Bb occurs via the Fab portion of the molecule. Pepsin treatment of eight C3NeF preparations resulted in an average loss of 76% of C3NeF functional activity. Papain treatment induced a loss of approximately 90%. The decrease in functional activity could be attributed to the accelerated rate of dissociation of 125I-F(ab')2 and 125I-Fab fragments from stabilized cell-bound C3b,Bb. The dissociation rate of 125I-F(ab')2 from C3b,Bb was comparable with the decay of the functional activity of C3b,Bb stabilized by F(ab')2 or Fab fragments of C3NeF. Although these results suggest that the stabilizing activity of C3NeF is mediated by the Fab portion of the molecule, it was found that the Fc portion also contributes to its functional activity.

Antibodies↗
PubMed1979

Renal transplantation for patients with type I and type II membranoproliferative glomerulonephritis: serial complement and nephritic factor measurements and the problem of recurrence of disease.

Fourteen patients with membranoproliferative glomerulonephritis as their original kidney disease received 16 renal allografts. All 14 patients are alive, 11 currently have functioning allografts, and one graft was lost to recurrence of membranoproliferative glomerulonephritis. Originally depressed serum complement (C3) concentrations returned to normal soon after transplantation in those patients with no clinical evidence of recurrence. Two patients with type II membranoproliferative glomerulonephritis had recurrence of disease. Nephritic factor (C3NeF) was high in both these patients before they received their transplants and was absent soon thereafter. However, abnormally high levels were again detected in their course. The one recurrence of type I membranoproliferative glomerulonephritis was associated with depressed C3, Clq, C4 and factor B but without C3NeF activity. Despite warnings of "high risks/ and "high mortality" associated with renal transplants in patients with membranoproliferative glomerulonephritis, we, because of these results and a review of the literature, continue to recommend renal transplants from both living related (LRD) and cadaver (CAD) donors in otherwise suitable patients who have renal failure due to membranoproliferative glomerulonephritis.

Adolescent↗
PubMed1979

Hereditary angio-oedema and C3 nephritic factor--HL-A study.

In one family of twenty-four members hereditary angio-oedema was present in the family for six generations. The protein C1 esterase inactivator found in nine patients proved to be non-active in a functional test. Another anomaly found in the complementary system was labelled C3 nephritic factor without any renal, or other clinical symptoms. Study of HL-A haplotypes did not show any linkage with the loci A, B and C. Hereditary angio-oedema is a disease arising from a specific defect in the inactivator of the C1 esterase (C1 INA) which is a regulating component of the complement system (Donaldson & Evans, 1963). This system is of current interest because of its interaction with other mechanisms of inflammation. Moreover, some links have been discovered recently between HL-A and hereditary defects of complement. This paper reports new findings in a family with hereditary angio-oedema.

Angioedema↗
PubMed1978

Identification of nephritic factor as an immunoglobulin.

C3 nephritic factor (C3NeF) activity in sera from three patients with mesangiocapillary glomerulonephritis, one of whom had partial lipodystrophy, was found on chromatography to be associated with fractions containing IgG and no other detectable proteins. Immunoadsorption of IgG from these fractions with a highly purified anti-IgG removed the C3NeF, and the IgG, eluted after combination with the anti-IgG, retained C3NeF activity. In each case the isolated IgG with C3NeF activity was found to contain more than one subclass of IgG and both kappa and lambda chains, indicating that the immunoglobulin comprising C3NeF in these patients is heterogeneous and not monoclonal. The identification of C3NeF as an immunoglobulin suggests that it may be an autoantibody against antigenic determinants of complement components present in the C3 convertase of the alternative pathway.

Chromatography, Ion Exchange↗