Structural and allergenic properties of the fatty acid binding protein from shrimp Litopenaeus vannamei

Allergy. 2022 May;77(5):1534-1544. doi: 10.1111/all.15154. Epub 2021 Oct 30.


Background: The shrimp Litopenaeus vannamei is an important source of food allergens but its allergenic repertoire is poorly characterized. Cross-reactivity between crustacean and mites has been reported, with tropomyosin, the most relevant allergen involved. The aim of this study was to investigate the structural and immunological properties of a recombinant Fatty Acid Binding Protein (FABP) family from L. vannamei (LvFABP).

Methods: ELISA, skin prick test (SPT) and basophil activation assays were performed to determine IgE reactivity and allergenic activity of LvFABP. LC-MS/MS and Circular Dichroism experiments were done for structural analysis. B-cell epitope mapping with overlapping peptides, and cross-inhibition studies using human sera were done to identify antigenic regions and cross-reactivity.

Results: The recombinant LvFABP bound serum IgE from 27% of 36 shrimp allergic patients and showed allergenic activity when tested for basophil activation and SPT in a selected number of them. CD-spectroscopy of LvFABP revealed that the protein is folded with a secondary structure composed of mainly β-strands and a smaller fraction of α helices. This is consistent with molecular modelling results, which exhibit a typical β barrel fold with two α-helices and ten β-strands. Epitope mapping identified two IgE-binding antigenic regions and inhibition assays found high cross-reactivity between LvFABP and Blo t 13, mediated by the antigenic region involving amino acids 54 to 72.

Conclusions: Our results show that LvFABP is a shrimp allergen that cross reacts with the house dust mite allergen Blo t 13 and has allergenic activity, which suggest that it could be clinically relevant in case of shellfish allergy. This new allergen, named Lit v 13, will also help to understand basic mechanisms of sensitization to shrimp.

Keywords: Allergen and epitopes; IgE; basophils; bioinformatics; food allergy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Allergens
  • Animals
  • Chromatography, Liquid
  • Cross Reactions
  • Fatty Acid-Binding Proteins
  • Food Hypersensitivity* / diagnosis
  • Humans
  • Immunoglobulin E
  • Penaeidae*
  • Tandem Mass Spectrometry


  • Allergens
  • Fatty Acid-Binding Proteins
  • Immunoglobulin E