Related Experiment Videos
[Evolution of hepatic periovular granulomas in different types of repeated infections with S. mansoni in mice
Abstract:
Effects upon hepatic granulomas in Swiss albino mice after challenged exposures to S. mansoni are studied: the time between the previous and the challenged infections had a major influence on the number, size and histological features of granulomas in residual infections; 15 days delay has not stimulated any protection against the challenge which developed freely, while 6 months delay impeded the 2nd infection which was abortive. However, in spite of a 6 months delay observance, no stimulation of protective immunity was obtained when the level of the primary infection was of 50 cercariae, while this protection became effective when the rate of primo-infection reached 100 or 200 cercariae. Opinions differ on the part of primo-infection in the induction of a protective immunity. It seems that the rate of efficiency of primo-infection depends on the mean level of antigenicity of the infective cercariae.
Insights
The time between Schistosoma mansoni infections significantly impacts hepatic granuloma formation in mice. Longer delays and higher initial infection doses can lead to protective immunity against subsequent infections.
Area of Science:
- Immunology
- Parasitology
- Hepatology
Context:
- Schistosomiasis mansoni is a significant human parasitic disease.
- Hepatic granulomas are key pathological features of S. mansoni infection.
- Understanding immune responses to S. mansoni is crucial for developing effective treatments.
Purpose:
- To investigate the influence of time intervals between primary and secondary S. mansoni infections on hepatic granuloma development.
- To determine the role of primary infection dose in inducing protective immunity against challenge infections.
Summary:
- The study examined hepatic granulomas in Swiss albino mice following S. mansoni infection and re-exposure.
- A 15-day interval allowed free development of challenge infections, while a 6-month interval impeded the second infection.
- Protective immunity was not observed with a primary infection of 50 cercariae but was effective with 100-200 cercariae, suggesting antigenicity levels are critical.
Impact:
- Findings highlight the importance of infection timing and dose in modulating host immune responses to S. mansoni.
- This research contributes to understanding the complexities of protective immunity induction in schistosomiasis.
- Results may inform strategies for vaccine development or therapeutic interventions targeting S. mansoni infections.