Molecular transfer to Atlantic salmon ovulated eggs using liposomes

Abstract

The delivery of exogenous biomolecules into teleost eggs is currently mostly relying on the manual microinjection methods, which, due to their high costs and low throughput, are not economically feasible for large-scale aquaculture applications. The main objective of this study was to develop a convenient, simple immersion delivery model for unfertilized Atlantic salmon (Salmo salar L.) eggs using liposomes as a system for the delivery of selected molecules.

We used a lipophilic marker, Rhodamine B isothiocyanate (RBITC) dye, to follow liposomal uptake, marker release and marker distribution within incubated egg. We investigated the influence of the incubation time, liposome surface charges and liposome sizes on the uptake into the eggs. After incubation with liposomes, the exposed eggs were fertilized and embryonic development was monitored until complete yolk sac absorption. The result showed that RBITC, was successfully delivered to the yolk of the incubated eggs. Moreover, during embryonic development, liposomal RBITC remained in the yolk sac until the yolk was completely absorbed. The findings demonstrated a novel approach for the delivery of exogenous molecules to unfertilized Atlantic salmon eggs, opening an avenue for large-scale aquaculture therapeutic applications.