Insight analysis of the cross sensitisation of multiple fish parvalbumins via the Th1/Th2 immunological balance and cytokine release from the perspective of safe consumption of fish

Parvalbumin is the primary allergen found in fish and is highly conserved. According to some studies, some patients with fish allergy are allergic to only one species of fish but are tolerant to others; however, the underlying mechanism has not been identified. The cross reactivity of these seven fish parvalbumins based on turbot PV treated mice was determined using BALB/c mouse and RBL-2H3 cell models. Meanwhile, immunoinformatic tools were used to assess cross reactivity. The results indicated that the seven species of fishes (turbot, large yellow croaker, sea bass, grass carp, common carp, conger eel and Japanese eel) studied exhibited varying degrees of cross reactivity, with the highest cross reactivity being between turbot and bass and the lowest being between turbot and conger eel. The bioinformatics analysis revealed that the sequence homology of parvalbumin between conger eel and turbot was the lowest, which may account for the conger eel and turbot cross reaction being so limited. Parvalbumin was a potent cross-reactive allergen found in turbot, large yellow croaker, sea bass, grass carp, common carp, conger eel and Japanese eel, and the cross reactivity between conger eel and turbot parvalbumin was the weakest. This study demonstrated that the cross reactivity between conger eel PV and turbot PV was the weakest.