Protective immunity against Brugia malayi by monoclonal antibodies

Research Project

Project/Area Number	61570190
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	寄生虫学(含医用動物学）
Research Institution	University of Tokyo
Principal Investigator	HAYASHI Yoshihiro Institute of Medical Science, University of Tokyo, 医科学研究所, 助教授 (90092303)
Co-Investigator(Kenkyū-buntansha)	NOGAMI Sadao Institute of Medical Science, University of Tokyo, 医科学研究所, 助手 (90172767)
Project Period (FY)	1986 – 1987
Project Status	Completed (Fiscal Year 1987)
Budget Amount *help	¥1,800,000 (Direct Cost: ¥1,800,000) Fiscal Year 1987: ¥400,000 (Direct Cost: ¥400,000) Fiscal Year 1986: ¥1,400,000 (Direct Cost: ¥1,400,000)
Keywords	Brugia malayi / Filariasis / Protective immunity / ミクロファラリア / Brugia malayi / 感染防御 / T細胞移入 / ミクロフィラリア / γ線照射 / BALB / C
Research Abstract	More than 20 monoclonal antibodies generated against human filarial parasite, Brugia malayi, were assayed for the ability to protect against infective and early L4 larvae in BALB/c mice. The monoclonal antibodies were injected intraperitoneally immediately before challenge infection with 100 L3 of B. malayi. However, non of them revealed significant reduction in worm recovery. Then, mice were immunized with affinity purified antigens from microfilariae using monoclonal antibodies, and were examined worm burden two weeks after challenge infection. In mice immunized with antigens purified with an IgM monoclonal antibody (Ov H), more than 70% reduction in worm recovery were observed. Microfilarial antigens were fractionated according to molecular weights using SDS-PAGE. Protective immunity was measured in mice immunized with these fractionated antigens. More than 90% reduction in worm recovery were observed in mice immunized with 33-35 or 40-45 KDa antigens. On the other hand, significant reduction was not shown in mice immunized with 60-170 KDa antigens. The results indicate that murine model may be a useful tool to evaluate the protection against challenge infection of Brugia malyi and be a reliable and time-saving model to purify the protective antigens for vaccine development.