Identification of Horse Anti-Ferritin Autoantibody

Orino, Koichi; S, Hamada; Hashimoto, M; Nambo, Yasuo; Kondo, Takashi; Watanabe, Kiyotaka

doi:10.1294/jes.17.113

Cited by 8 publications

(25 citation statements)

References 32 publications

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“…Although the biochemical properties of the purified novel FBP are different from those reported in other animals, such as H-kininogen (Torti and Torti 1998), a-2-macroglobulin (Santambrogio and Massover 1989;Massover 1994), apoB (Seki et al 2008), fibrinogen (Orino et al 1993b), and anti-ferritin autoantibodies (Orino et al 2004(Orino et al , 2006a, our attempt to identify the novel feline FBP was unsuccessful. The serum concentration of feline FBP was estimated to be approximately 20 lg ml -1 from the results shown in Figs.…”

Section: Discussionmentioning

confidence: 76%

“…The 3 M KSCN eluate showed the same result as the 0.5 M (NH 4 ) 2 SO 4 eluate according to immunoblot analysis (data not shown). Therefore, feline FBP was identified as anti-ferritin autoantibodies (IgM, IgG, and IgA) as in canine (Orino et al 2006b), horse (Orino et al 2006a), and bovine (Orino et al 2004). We could not detect any effect of 3 M KSCN eluate on the ferritin immunoassay due to non-specific reactions causing binding to the well of the plate, followed by binding with biotinylated antibody for unknown reasons (data not shown).…”

Section: Discussionmentioning

confidence: 99%

“…Although the physiological roles of these FBPs have not been fully established, FBPs may be involved in the clearance of circulating ferritins after forming complexes with them (Covell et al 1984;Santambrogio and Massover 1989;Orino et al 2004Orino et al , 2006a. In mammals, although a-2-macroglobulin is known to be a common FBP (Santambrogio and Massover 1989;Massover 1994), we proposed that mammalian anti-ferritin autoantibody is also a common FBP (Orino and Watanabe 2008).…”

Section: Introductionmentioning

confidence: 91%

“…A variety of ferritin-binding proteins (FBPs) in mammalian serum and/or plasma have been described: H-kininogen (Torti and Torti 1998) and apolipoprotein B (apoB) (Seki et al 2008) in human serum; a-2-macroglobulin in rabbit and horse serum (Santambrogio and Massover 1989;Massover 1994); anti-ferritin autoantibody in canine, horse, and bovine serum (Orino et al 2004(Orino et al , 2006a; and fibrinogen in horse plasma (Orino et al 1993b). Although the physiological roles of these FBPs have not been fully established, FBPs may be involved in the clearance of circulating ferritins after forming complexes with them (Covell et al 1984;Santambrogio and Massover 1989;Orino et al 2004Orino et al , 2006a.…”

Section: Introductionmentioning

confidence: 99%

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Characterization of feline serum ferritin-binding proteins: the presence of a novel ferritin-binding protein as an inhibitory factor in feline ferritin immunoassay

et al. 2009

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Ferritin-binding proteins (FBPs) such as anti-ferritin antibody, alpha-2-macroglobulin, apolipoprotein B are expected to interact with circulating ferritin to eliminate it from circulation. However, we found that feline serum more strongly inhibits the detection of canine liver ferritin by immunoassay than its apoferritin; putative FBPs probably conceal ferritin epitopes detected by anti-ferritin antibodies. After complex formation between affinity-purified FBPs and canine liver ferritin, co-immunoprecipitates of the complex by anti-bovine spleen ferritin antibody were found to contain autoantibodies (IgG, IgM, and IgA) to ferritin by immunoblot analysis with antibodies specific for feline IgG, IgM, and IgA. On the other hand, affinity-purified samples did not show any inhibitory effect in the ferritin immunoassay. This result shows that feline serum has another FBP, which inhibits ferritin immunoassays, but not anti-ferritin autoantibody. A feline FBP was partially purified from feline serum by (NH(4))(2)SO(4) fractionation (33-50%), gel filtration chromatography, and anion exchange chromatography. After binding of the partially purified sample with canine liver ferritin coupled-Sepharose gel, the FBP was separated and purified from complexes formed in a native-PAGE gel. SDS-PAGE analysis showed that the purified FBP is a homomultimer composed of 31 kDa monomeric subunits connected by intermolecular disulfide bonds. Detection of feline liver ferritin by immunoassay was inhibited by FBP in a dose-dependent manner. The purified protein molecules appeared to be conglomerate of pentraxin-like molecules by its electron micrographic appearance. These results demonstrate that feline serum contains a novel FBP as inhibitory factor of ferritin immunoassay with different molecular properties from those of other mammalian FBPs, in addition to auto-antibodies (IgG, IgM, and IgA) to ferritin.

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Section: Discussionmentioning

confidence: 76%

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 91%

Section: Introductionmentioning

confidence: 99%

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Characterization of feline serum ferritin-binding proteins: the presence of a novel ferritin-binding protein as an inhibitory factor in feline ferritin immunoassay

et al. 2009

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“…A variety of ferritin-binding proteins (FBPs) in mammalian circulation systems have been identified: H-kininogen [14], alpha-2-macroglobulin [15,16], autoantibodies [17][18][19][20][21], apolipoprotein B [22] and fibrinogen [23]. These proteins are likely involved in the clearance of circulating ferritin through indirect receptor-mediated uptake by forming complexes with it.…”

Section: Introductionmentioning

confidence: 99%

Characterization Analysis of Human Anti-Ferritin Autoantibodies

et al. 2014

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Anti-ferritin autoantibodies are found in many animals. Human ferritin-binding proteins (FBPs) were partially purified from human serum by ion-exchange chromatography and immobilized metal affinity chromatography with Zn 2+ . Crude FBPs were immunocoprecipitated with canine liver ferritin followed by the addition of anti-ferritin antibodies. Immunoglobulins in the immunocoprecipitate were detected with antibodies specific for human IgG, IgM or IgA heavy chains, and immunoglobulins IgG, IgM and IgA to bind to expressed recombinant human H and L chain homopolymers were also found. A portion of human serum proteins bound to zinc ions immobilized on beads were released upon the addition of canine liver ferritin, and the released protein was identified as IgM antibody. Additionally, the released proteins recognized peptide sequence (DPHLCDF) commonly found in amino acid sequences of mammalian ferritin H and L subunits. These results suggest that human serum contains anti-ferritin autoantibodies (IgG, IgM and IgA) which bind zinc ions and preferentially bind ferritin over both the H and L subunits, and that a portion of, but not all, the IgM antibodies bound to ferritin with higher affinity than to zinc ions and may recognize the common sequence found in mammalian ferritin H and L subunits.

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