TY - JOUR
T1 - Nattokinase (Bac s 1), a subtilisin family serine protease, is a novel allergen contained in the traditional Japanese fermented food natto
AU - Suzuki, Kayoko
AU - Nakamura, Masashi
AU - Sato, Nayu
AU - Futamura, Kyoko
AU - Matsunaga, Kayoko
AU - Yagami, Akiko
N1 - Publisher Copyright:
© 2022 Japanese Society of Allergology
PY - 2023/4
Y1 - 2023/4
N2 - Background: Immediate allergy caused by natto, a popular Japanese food prepared by fermenting soybeans with Bacillus subtilis var. natto, has been reported. Polygamma glutamic acid (PGA) in the sticky substance around natto beans has been reported to be a causative allergen of natto allergy. However, some of our patients with natto allergy were negative for PGA in the skin prick test (SPT). The sticky substance of natto beans contains a subtilisin family serine protease, nattokinase, along with PGA. In this study, we aimed to examine the antigenicity of nattokinase in natto allergy. Methods: Eight patients, who developed symptoms after ingesting natto and positively reacted to natto (seven to the sticky substance in natto and one to the whole natto product) in their SPT, were enrolled in this study. To analyze IgE reactivity, we performed immunoblotting, ELISA, and SPT for natto (bean and sticky substance), and/or PGA, and/or nattokinase and/or cultured B. subtilis var. natto extract. Results: In the SPT, four cases each were PGA-positive and PGA-negative. Immunoblotting of the sera from PGA-negative patients showed a protein band at 30 kDa, which was identified as nattokinase. Three PGA-negative cases, but not three PGA-positive cases, showed a positive reaction to nattokinase in the SPT and had a history of atopic dermatitis. The ELISA for nattokinase revealed a positive reaction of PGA-negative cases and negative reaction of PGA-positive cases in the SPT. Conclusions: We identified a subtilisin family serine protease, nattokinase, as a novel allergen in natto allergy patients unsensitized to PGA.
AB - Background: Immediate allergy caused by natto, a popular Japanese food prepared by fermenting soybeans with Bacillus subtilis var. natto, has been reported. Polygamma glutamic acid (PGA) in the sticky substance around natto beans has been reported to be a causative allergen of natto allergy. However, some of our patients with natto allergy were negative for PGA in the skin prick test (SPT). The sticky substance of natto beans contains a subtilisin family serine protease, nattokinase, along with PGA. In this study, we aimed to examine the antigenicity of nattokinase in natto allergy. Methods: Eight patients, who developed symptoms after ingesting natto and positively reacted to natto (seven to the sticky substance in natto and one to the whole natto product) in their SPT, were enrolled in this study. To analyze IgE reactivity, we performed immunoblotting, ELISA, and SPT for natto (bean and sticky substance), and/or PGA, and/or nattokinase and/or cultured B. subtilis var. natto extract. Results: In the SPT, four cases each were PGA-positive and PGA-negative. Immunoblotting of the sera from PGA-negative patients showed a protein band at 30 kDa, which was identified as nattokinase. Three PGA-negative cases, but not three PGA-positive cases, showed a positive reaction to nattokinase in the SPT and had a history of atopic dermatitis. The ELISA for nattokinase revealed a positive reaction of PGA-negative cases and negative reaction of PGA-positive cases in the SPT. Conclusions: We identified a subtilisin family serine protease, nattokinase, as a novel allergen in natto allergy patients unsensitized to PGA.
UR - http://www.scopus.com/inward/record.url?scp=85144983354&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85144983354&partnerID=8YFLogxK
U2 - 10.1016/j.alit.2022.11.010
DO - 10.1016/j.alit.2022.11.010
M3 - Article
C2 - 36517353
AN - SCOPUS:85144983354
SN - 1323-8930
VL - 72
SP - 279
EP - 285
JO - Allergology International
JF - Allergology International
IS - 2
ER -