Multi-omic analysis of Tyrophagus putrescentiae reveals insights into the allergen complexity of storage mites

Genome-Wide Identification and Comparative Analysis of Allergens in Procambarus clarkii

PURPOSE

Crustacean shellfish is one of the eight most common food allergens, and crayfish is a highly valued shellfish species for consumption in China. However, the detailed allergen profile of crayfish remains unknown, with only four allergen groups reported in the WHO/IUIS allergen nomenclature database. In this study we aimed to identify novel allergens based on the Procambarus clarkii genome and to reveal its allergen profile for developing better diagnostic tools and treatments.

METHODS

We assembled the crayfish genome using both long-read and short-read sequencing data and identified putative allergens using the BLAST algorithm based on sequence homology. We employed bioinformatics tools to investigate the expression levels, gene structure, and synteny of these putative allergens. We also applied indirect enzyme-linked immunosorbent assay by using patients' sera to determine allergenicity and utilized proteomic methods to identify novel allergens.

RESULTS

We identified a total of 11 putative allergen groups, including all isoforms or homologs for each allergen group based on the genome and three putative allergens by using 2-dimensional (2D) mass spectrometry. We identified 2 novel allergens, pPro c 3.0301 and pPro c 6.0201, with immunoglobulin E reactivity of 33.3% and 20%, respectively.

CONCLUSIONS

By providing a comprehensive understanding of the complete allergen profile, our study presents a foundation for comprehending P. clarkii-associated allergy. The knowledge could facilitate the implementation of a components-resolved diagnostic test and preventive immunotherapy based on molecular allergens for crayfish allergy.

Comparative analysis of cysteine proteases reveals gene family evolution of the group 1 allergens in astigmatic mites

BACKGROUND

Astigmatic mites contain potent allergens that can trigger IgE-mediated immune responses, leading to allergic diseases such as asthma, allergic rhinitis and atopic dermatitis. In house dust mites Dermatophagoides pteronyssinus and Dermatophagoides farinae, group 1 allergens (Der p 1 and Der f 1), characterized as papain-like cysteine proteases, have been defined as the major allergens that have high prevalence and potency. Previous studies of mite group 1 allergens mainly focused on identification, comparison of sequence and structure, as well as the investigation of cross-reactivity. To achieve a comprehensive view of mite group 1 allergens, we performed a comparative genomic analysis of all the cysteine proteases in six astigmatic mite species to elucidate the evolutionary relationships of group 1 allergens.

METHODS

Based on the high-quality and annotated genomes, all the cysteine proteases in six astigmatic mite species were identified by sequence homology search. The phylogenetic relationships, gene synteny and expression levels were revealed by bioinformatic tools. The allergenicity of recombinant cysteine proteases was evaluated by enzyme-linked immunosorbent assay.

RESULTS

Tandem duplication was revealed as the major feature of cysteine protease gene evolution in astigmatic mites. The high IgE-binding capacity and the significant expression level of the cysteine protease DP_007902.01 suggested its potential as a novel group 1 allergen of D. pteronyssinus. In addition, gene decay events were identified in the skin-burrowing parasitic mite Sarcoptes scabiei.

CONCLUSION

This comprehensive analysis provided insights into the evolution of cysteine proteases, as well as the component-resolved diagnosis of mite allergies.