A Novel Method for Measuring Unbound Serum Bilirubin Levels Using Glucose Oxidase-Peroxidase and Bilirubin-Inducible Fluorescent Protein

• Project/Area Number: 15K19652
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Embryonic/Neonatal medicine
• Research Institution: Kobe University
• Principal Investigator: Iwatani Sota 神戸大学, 医学部附属病院, 助教 (00741430)
• Co-Investigator(Renkei-kenkyūsha): NAKAMUTA Hajime 神戸大学, 大学院医学研究科・内科系講座小児科学分野, 名誉教授 (40030978) ; MORIOKA Ichiro 神戸大学, 大学院医学研究科・内科系講座こども急性疾患学, 特命教授 (80437467)
• Project Period (FY): 2015-04-01 – 2017-03-31
• Project Status: Completed (Fiscal Year 2016)
• Budget Amount: ¥3,510,000 (Direct Cost: ¥2,700,000、Indirect Cost: ¥810,000); Fiscal Year 2016: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000); Fiscal Year 2015: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000)
• Keywords: unconjugated bilirubin / unbound bilirubin / measurement method / fluorescent protein / UnaG / bilirubin / fluorescent

Outline of Final Research Achievements

Increased serum levels of unconjugated bilirubin (UCB), especially in unbound bilirubin (UB), are associated with the development of brain damage in newborns. In current clinical settings, there are no standard methods for serum levels of UCB and UB. UnaG, a fluorescent protein from Japanese eel muscle that specifically binds to UCB was used in this study. UCB levels measured by the UnaG method were highly correlated with those determined by conventional bilirubin oxidase assay. The performance of the UnaG assay was unaffected by phototherapy and the presence of serum conjugated bilirubin or hemoglobin. These results demonstrate the clinical applicability of the UnaG method for measurement of UCB levels in newborn serum. To date, we have established a novel method for measuring UB levels using glucose oxidase-peroxidase and the UnaG assay (Patent PCT/JP2015/074542).

Research Products

• [Journal Article] Fluorescent protein-based detection of unconjugated bilirubin in newborn serum (2016)
  • Author(s): Sota Iwatani, Hajime Nakamura, Daisuke Kurokawa, Keiji Yamana, Kosuke Nishida, Sachiyo Fukushima, Tsubasa Koda, Noriyuki Nishimura, Hisahide Nishio, Kazumoto Iijima, Atsushi Miyawaki, Ichiro Morioka
  • Journal Title: Scientific Reports Volume: 6 Issue: 1 Pages: 1-8
  • DOI: 10.1038/srep28489
  • NAID: 120005819328
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Presentation] ここまで来た、臨床応用を視野に入れたUnaGによるビリルビン測定研究 (2016)
  • Author(s): 岩谷 壮太
  • Organizer: 黄疸管理研究会
  • Place of Presentation: 大阪
  • Year and Date: 2016-10-03
  • Invited
• [Presentation] 12.ビリルビン誘導蛍光タンパク質（UnaG）を用いた新たな新生児血清中の非抱合型ビリルビン濃度測定法 (2016)
  • Author(s): 岩谷 壮太
  • Organizer: 日本周産期新生児学会
  • Place of Presentation: 福岡
  • Year and Date: 2016-07-10
• [Presentation] A Novel Method for Measuring Unbound Serum Bilirubin Levels Using Glucose Oxidase-Peroxidase and Bilirubin-Inducible Fluorescent Protein (2016)
  • Author(s): Sota Iwatani
  • Organizer: Pediatric Academic Society Meeting
  • Place of Presentation: Baltimore
  • Year and Date: 2016-04-30
  • Int'l Joint Research
• [Presentation] A novel measurement method for serum unconjugated bilirubin concentrations using a bilirubin-inducible fluorescent protein (2015)
  • Author(s): Sota Iwatani
  • Organizer: Pediatric Academic Society Meeting
  • Place of Presentation: SanDiego
  • Year and Date: 2015-04-25
  • Int'l Joint Research
• [Remarks] ニホンウナギの光るたんぱく質UnaGによるビリルビン測定-赤ちゃんの黄疸管理の改善へ
  • URL: http://www.kobe-u.ac.jp/NEWS/research/2016_06_21_02.html
• [Patent(Industrial Property Rights)] 血液試料中のアンバウンドビリルビンの測定方法 (2016)
  • Inventor(s): 岩谷 壮太
  • Industrial Property Rights Holder: 岩谷 壮太
  • Industrial Property Rights Type: 特許
  • Filing Date: 2016-03-30
  • Overseas