Immunity mediates host specificity in the human hookworm Ancylostoma ceylanicum

Area of Science:

• Parasitology
• Immunology
• Host-pathogen interactions

Background:

• Hookworm infections cause significant global health issues, including malnutrition and anemia.
• Ancylostoma ceylanicum is a generalist hookworm infecting various hosts, but not mice.
• Host specificity in parasitic infections is a critical factor in disease transmission.

Purpose of the Study:

• To investigate the development of Ancylostoma ceylanicum in immunodeficient NSG mice.
• To determine the role of the immune system in restricting Ancylostoma ceylanicum host specificity.
• To establish a model for studying hookworm development in mice.

Main Methods:

• Infection of immunodeficient NSG mice with Ancylostoma ceylanicum.
• Monitoring of patent infections and egg production.
• Testing infectivity of larvae from NSG mice to hamsters.
• Comparison with Ancylostoma ceylanicum development in Swiss Webster mice.
• Comparison with Ancylostoma caninum infection in NSG mice.

Main Results:

• Ancylostoma ceylanicum infections became patent in NSG mice by day 19 post-infection.
• Sustained high egg production was observed for at least 160 days in NSG mice.
• Larvae from NSG mice successfully infected hamsters, indicating viable offspring.
• Limited development of Ancylostoma ceylanicum occurred in Swiss Webster mice.
• Ancylostoma caninum failed to infect NSG mice.

Conclusions:

• The immune system plays a crucial role in the host restriction of Ancylostoma ceylanicum.
• Immunodeficient NSG mice support the complete life cycle of Ancylostoma ceylanicum.
• This study provides the first report of hookworm completing its life cycle in mice.
• Different mechanisms likely govern host specificity in closely related hookworm species.