Fish immune responses against endoparasitic nematodes - experimental models

Area of Science:

• Comparative immunology
• Parasitology
• Fish health

Background:

• Vertebrates exhibit immune responses to helminth infections, developing resistance to subsequent invasions.
• Concomitant immunity in mammals involves a trade-off between parasite control and host pathology, favoring the isolation of live parasites.
• Mammalian antihelminthic responses are characterized by a shift from Th1 to Th2 lymphocyte responses.

Purpose of the Study:

• To outline the main immune reactions in fish against helminths.
• To investigate alternative immune pathways in fish lacking specific mammalian immune components, such as Atlantic cod.
• To propose experimental fish models for studying antihelminthic immunity.

Main Methods:

• Review of existing literature on vertebrate and teleost immunology.
• Analysis of immune mechanisms in fish infected with nematodes.
• Proposal of experimental models for further research.

Main Results:

• Fish, like mammals, mount immune responses to helminths, involving both innate and adaptive immunity.
• Atlantic cod (Gadus morhua L.) possess distinct immune pathways, lacking key elements found in mammalian Th1/Th2 responses.
• Salmonid fish may exhibit immune responses more similar to mammals.

Conclusions:

• Fish exhibit diverse immune strategies against helminths, with variations across species.
• Understanding these fish immune pathways is crucial for advancing fish health and aquaculture.
• Experimental models are proposed to elucidate these alternative antihelminthic immune mechanisms in fish.