Grant-in-Aid for Scientific Research (B)
|Allocation Type||Single-year Grants |
|Research Institution||Aichi Medical University |
KIMURA Eisaku Aichi Medical University, School of Medicine, Professor, 医学部, 教授 (70153187)
HIRAYAMA Kenji Nagasaki Univ., Institute of Tropical Medicine, Professor, 熱帯医学研究所, 教授 (60189868)
ITOH Makoto Aichi Medical University, School of Medicine, Associate Professor, 医学部, 助教授 (90137117)
TAKAGI Hidekazu Aichi Medical University, School of Medicine, Assistant, 医学部, 助手 (90288522)
ISOGAI Yoshinori Nihon Fukushi Univ., Faculty of Social and Information Science, Professor, 情報社会科学部, 教授 (60079697)
藤巻 康教 長崎大学, 熱帯医学研究所, 講師 (10209083)
|Project Period (FY)
2002 – 2005
Completed (Fiscal Year 2004)
|Budget Amount *help
¥11,900,000 (Direct Cost: ¥11,900,000)
Fiscal Year 2004: ¥3,400,000 (Direct Cost: ¥3,400,000)
Fiscal Year 2003: ¥3,300,000 (Direct Cost: ¥3,300,000)
Fiscal Year 2002: ¥5,200,000 (Direct Cost: ¥5,200,000)
|Keywords||filariasis / immunodiagnosis / immunoglobulin G4 (IgG4) / urine ELISA / Wuchereria bancrofti / IgG4 / 尿 / 国際研究者交流 / スリランカ / マレー糸状虫 / スリランカ;インド;ケニア / スリランカ:中国:インド|
We have developed a new immunodiagnostic method that uses urine as samples (urine ELISA with the sensitivity of 96.5% and the specificity of 99.0%). The method was tested for the usefulness in field studies.
1.Urine ELISA for measuring the intensity of infection
A big advantage of urine ELISA is its ease in applying the method to young children. They are a sentinel population that can indicate new filarial infections. (We have confirmed that IgG4 transferred from infected mothers to their new born babies disappeared within a year.) In a high endemic area in Sri Lanka, the IgG4 positive appeared at age 1 year, and the antibody titers reached a high level by age 3. In a low endemic area in Thailand, the positive appeared at around 10 years, and showed a high titer level after 20 years of age. In a filariasis-disappeared area in Korea, there was no positive before 40 years of age.
2.Urine ELISA for evaluating Mass Drug Administration (MDA), and confirming elimination of filariasis
4 levels were studied with schoolchildren in Deniyaya area, Sri Lanka, before and after MDA. After treatment, the positive rate and titers of specific IgG4 reduced clearly, suggesting that urine ELISA is useful to monitor a MDA program. Also in 2 Chinese villages, where filariasis elimination had been confirmed, all of more than 10,000 schoolchildren examined were confirmed negative with the ELISA.
3.Making a filariasis distribution map based on information given by local people
Questionnaires were mailed to local leaders, asking the presence and the number of elephantiasis and hydrocele cases in their villages. The study revealed many villages with the cases, where filariasis had not been reported before. Immunoepidemiological studies using urine ELISA showed a possible filariasis transmission in such villages.
4.Development of new diagnostic methods using recombinant proteins.
Recombinant SXP-1 and endochitinase proteins were used for this study successfully. The former seems to be particularly promising.
5.Genetic analysis of families with more than 1 elephantiasis case
This study is going on and some interesting findings are being accumulated. Less