TY - JOUR
T1 - Specific strains of Streptococcus mutans, a pathogen of dental caries, in the tonsils, are associated with IgA nephropathy
AU - Ito, Seigo
AU - Misaki, Taro
AU - Naka, Shuhei
AU - Wato, Kaoruko
AU - Nagasawa, Yasuyuki
AU - Nomura, Ryota
AU - Otsugu, Masatoshi
AU - Matsumoto-Nakano, Michiyo
AU - Nakano, Kazuhiko
AU - Kumagai, Hiroo
AU - Oshima, Naoki
N1 - Funding Information:
This work was partially supported by JSPS KAKENHI (Nos JP19K10098). We thank Prof. Masashi Tsunoda (Department of Preventive Medicine and Public Health, National Defense Medical College) for the kind support as well as our colleague Keiko Komoda for the expert secretarial assistance.
Funding Information:
Ethics. This study was conducted in full adherence to the Declaration of Helsinki (64th WMA General Assembly, Fortaleza, Brazil, 2013), and the study protocol was approved by the Ethics Committee of National Defense Medical College (approval no. 2690) and Seirei Hamamatsu General Hospital (approval no. 1807). All subjects were informed about the protocol and provided written consent prior to their participation.
Publisher Copyright:
© 2019, The Author(s).
PY - 2019/12/1
Y1 - 2019/12/1
N2 - Streptococcus mutans is known to be a major causative agent of dental caries, and strains expressing the cell surface collagen-binding Cnm protein contribute to the development of several systemic diseases. A relationship between tonsillar immunity and glomerulonephritis has been recognized in IgA nephropathy (IgAN), and specific pathogens may have effects on tonsillar immunity (mucosal immunity). Here, we present findings showing a relationship between the presence of Cnm-positive S. mutans strains in the tonsils of IgAN patients and IgAN condition/pathogenesis. Analyses of tonsillar specimens obtained from patients with IgAN (n = 61) and chronic tonsillitis (controls; n = 40) showed that the Cnm protein-positive rate was significantly higher in IgAN patients. Among IgAN patients, the tonsillar Cnm-positive group (n = 15) had a significantly higher proportion of patients with high urinary protein (>1.5 g/gCr) and lower serum albumin level than the Cnm-negative group (n = 46). Additionally, Cnm protein and CD68, a common human macrophage marker, were shown to be merged in the tonsils of IgAN patients. These findings suggest that Cnm-positive S. mutans strains in the tonsils may be associated with severe IgAN.
AB - Streptococcus mutans is known to be a major causative agent of dental caries, and strains expressing the cell surface collagen-binding Cnm protein contribute to the development of several systemic diseases. A relationship between tonsillar immunity and glomerulonephritis has been recognized in IgA nephropathy (IgAN), and specific pathogens may have effects on tonsillar immunity (mucosal immunity). Here, we present findings showing a relationship between the presence of Cnm-positive S. mutans strains in the tonsils of IgAN patients and IgAN condition/pathogenesis. Analyses of tonsillar specimens obtained from patients with IgAN (n = 61) and chronic tonsillitis (controls; n = 40) showed that the Cnm protein-positive rate was significantly higher in IgAN patients. Among IgAN patients, the tonsillar Cnm-positive group (n = 15) had a significantly higher proportion of patients with high urinary protein (>1.5 g/gCr) and lower serum albumin level than the Cnm-negative group (n = 46). Additionally, Cnm protein and CD68, a common human macrophage marker, were shown to be merged in the tonsils of IgAN patients. These findings suggest that Cnm-positive S. mutans strains in the tonsils may be associated with severe IgAN.
UR - http://www.scopus.com/inward/record.url?scp=85077160011&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85077160011&partnerID=8YFLogxK
U2 - 10.1038/s41598-019-56679-2
DO - 10.1038/s41598-019-56679-2
M3 - Article
C2 - 31882880
AN - SCOPUS:85077160011
SN - 2045-2322
VL - 9
JO - Scientific reports
JF - Scientific reports
IS - 1
M1 - 20130
ER -
