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Updated: Jan 24, 2026

Author Spotlight: Investigating the Potential of Chinese Herbal Medicinal Active Dioscin in Treating IgA Nephropathy
Published on: October 13, 2023
Binding of IgA1 and surface-expressed collagen-binding protein of Streptococcus mutans contributes to IgA nephropathy
Daiki Matsuoka1, Kana Suehara1, Shuhei Naka1
1Department of Pediatric Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Okayama, Japan.
Background:
The present study was conducted to examine the interaction between collagen-binding protein (Cnm) of Streptococcus mutans and immunoglobulin (IgA) to clarify the possible involvement in IgA nephropathy (IgAN) development.
Methods:
The binding of Cnm to human immunoglobulins was examined using an enzyme-linked immunosorbent assay. A nephritis-induced rat model was employed to confirm the localization of Cnm.
Results:
IgA1 showed significantly greater binding ability to Cnm than to other bacterial surface proteins, and Cnm showed significantly greater binding ability to IgA1 than to other immunoglobulins. In rats administered Cnm, IgA deposition was observed in the glomerular mesangial region. Furthermore, biotin-labeled Cnm was observed in the same region as IgA deposition in the Cnm group.
Conclusions:
Taken together, it is considered that following invasion into the bloodstream, Cnm binds to and forms a complex with IgA1, leading to deposition of IgA1 in renal glomeruli.
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