PMID- 3430967
OWN - NLM
STAT- MEDLINE
DCOM- 19880309
LR  - 20190725
IS  - 0085-2538 (Print)
IS  - 0085-2538 (Linking)
VI  - 32
IP  - 6
DP  - 1987 Dec
TI  - Complement activation in experimental IgA nephropathy: an antigen-mediated 
      process.
PG  - 838-44
AB  - Complement activation associated with immune complex glomerular deposition plays 
      an important role in renal injury. In the present studies we performed three 
      series of experiments to identify how IgA immune complexes activate complement. 
      The first series of experiments was designed to determine whether the presence of 
      an antigen within a glomerular IgA immune deposit is required for complement 
      activation. In these experiments, large-sized covalently cross-linked IgA 
      oligomers (X-IgA) were prepared with purified IgA anti-dinitrophenyl (DNP) and a 
      bivalent affinity-labeling antigen, bis-2,4-DNP-pimelic acid ester. These X-IgA 
      oligomers have free antigen-binding sites that will bind DNP-conjugated antigens. 
      Two groups of mice were treated with either X-IgA or X-IgA followed, after two 
      hours, by an antigen DNP-Ficoll. Immunofluorescent examination of renal tissues, 
      obtained six hours after the initial injection, revealed an equal intensity of 
      IgA glomerular deposits in both groups of mice. Glomerular C3 deposits were only 
      detectable in the renal tissues of mice that had DNP-Ficoll bound to X-IgA. In 
      the second series of experiments, a pair of preformed IgA immune complexes, 
      differing only in one antigenic structural feature (DNP), were used to examine 
      the role of the antigen in inducing glomerular C3 deposits in two groups of mice. 
      These pre-formed immune complexes were prepared with IgA anti-phosphorylcholine 
      (PC) and either PC-conjugated to bovine serum albumin (PC-BSA) or PC-BSA which 
      was further modified with DNP (PC/DNP-BSA). Although the IgA immunofluorescent 
      intensity and pattern in the glomerular deposits were equivalent for both groups, 
      intense C3 deposits were exclusively associated with the PC/DNP-BSA-containing 
      immune complexes. Analysis of the relative conversion of normal human serum C3 to 
      inactive C3b (iC3b) by X-IgA, various antigens and their respective IgA immune 
      complexes was highly dependent on the nature of the antigen.(ABSTRACT TRUNCATED 
      AT 250 WORDS)
FAU - Rifai, A
AU  - Rifai A
AD  - Department of Pathology and Laboratory Medicine, University of Texas Health 
      Science Center, Houston.
FAU - Chen, A
AU  - Chen A
FAU - Imai, H
AU  - Imai H
LA  - eng
GR  - AM 32379/AM/NIADDK NIH HHS/United States
PT  - Journal Article
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - Kidney Int
JT  - Kidney international
JID - 0323470
RN  - 0 (Antigen-Antibody Complex)
RN  - 0 (Complement C3)
RN  - 0 (Immunoglobulin A)
SB  - IM
MH  - Animals
MH  - Antigen-Antibody Complex/*immunology
MH  - *Complement Activation
MH  - Complement C3/analysis
MH  - Disease Models, Animal
MH  - Female
MH  - Glomerulonephritis, IGA/*immunology
MH  - Immunoglobulin A/analysis
MH  - Kidney Glomerulus/immunology
MH  - Mice
MH  - Mice, Inbred BALB C
EDAT- 1987/12/01 00:00
MHDA- 1987/12/01 00:01
CRDT- 1987/12/01 00:00
PHST- 1987/12/01 00:00 [pubmed]
PHST- 1987/12/01 00:01 [medline]
PHST- 1987/12/01 00:00 [entrez]
AID - S0085-2538(15)34154-5 [pii]
AID - 10.1038/ki.1987.284 [doi]
PST - ppublish
SO  - Kidney Int. 1987 Dec;32(6):838-44. doi: 10.1038/ki.1987.284.