Simultaneous determination of two major snow crab aeroallergens in processing plants by use of isotopic dilution tandem mass spectrometry

Abstract

Snow crab is a major fishery in the North Atlantic region. During crab processing the proteins are aerosolized and some are responsible for development of occupational asthma. Tropomyosin and arginine kinase have recently been reported as major snow crab allergens. A liquid chromatographic tandem mass spectrometric method has been developed for simultaneous analysis of these two proteins in air samples collected from processing plants. These proteins were initially isolated then characterized by use of mass spectrometry to determine their primary structure and signature peptides. The signature peptides were chemically synthesized in light and heavy forms and used as standards for developing the multiple-reaction monitoring transitions to monitor allergen levels. A validation study was performed; precision and accuracy were 1.8-8% and 91-104%, respectively. Replicate air samples were collected on air filters from two crab-processing plants in Newfoundland and Labrador (NL) and four located in Quebec. In NL, measured levels of both tropomyosin and arginine kinase were between 1 and 20 ng m(-3). In Quebec plants, however, levels were found to be much higher at 2-2400 ng m(-3). Significant differences were also observed among the plants and individual processing workstations. For the first time arginine kinase has been detected in its aerosolized form in processing plants. In general, levels of the allergens were highest in the butchering and cooking areas; plant design can, however, have a significant effect on levels of the allergens.

Lung function and prevalence of respiratory symptoms in Norwegian crab processing workers

“…There may also be a “plant effect” [20], where plant layouts and characteristics such as building sizes, ventilation and shielding of work tasks affect exposure levels. The processing procedures and use of automated machines during processing influence the workers’ exposure and may affect the development of diseases such as asthma [11,20]. Changes in processing equipment, ventilation and personal protective equipment worn by the workers may also change over time.…”

Comprehensive Proteomics Approach in Characterizing and Quantifying Allergenic Proteins from Northern Shrimp: Toward Better Occupational Asthma Prevention

“…For quantitative analysis of targeted airborne allergens, an isotopic dilution tandem MS method was developed for TM and AK, where their signature peptides were assigned from their protein sequence data. The criteria for selecting signature peptides were discussed elsewhere. , Accordingly, the best peptide with the highest score of identity was reported for TM and AK in northern shrimp as SEEEVFGLQK and QQLVDDHFLFVSGDR, respectively. The signature peptides were chemically synthesized, in both light and heavy forms, for developing the proper MRM transitions of the triple quadrupole mass spectrometer (Table ).…”

“…Personal breathing zone air samples were collected using PTFE filters attached to air pumps. The air sample collection for the allergen profile was recently standardized and has been followed in this study. , The samplers were deployed on workers toiling in cooking, peeling, and packing areas for 8 h of operation and shrimp processing. The target allergens were extracted from the filters using a standard protocol, and the eluted allergens were tryptic digested and then analyzed by LC–MS/MS. , The levels of both targeted allergens (TM and AK) were reported in Figure .…”

Multisyringe Flow Injection Analysis of Tropomyosin Allergens in Shellfish Samples

“…Tropomyosin was excised from the SDS-PAGE gel for mass spectrometric analysis. The SDS-PAGE bands between 34 and 40 kDa ( Appendix A ) were destained and digested with trypsin, according to the method designed by Abel Rahman et al [ 26 ], before injection into the LC/MS system. Tropomyosin quantification was based on IVELEEELR (sequence) peptide determination, as suggested by Wang et al [ 37 ].…”

“…Several bioanalytical methods for the detection of tropomyosin in shellfish have been developed, such as enzyme-linked immunosorbent assay (ELISA) [ 22 ] or polymerase chain reaction (PCR) methods [ 23 , 24 ] which have many drawbacks such as indirect detection of allergens, possibility of false positive/negative results, need for intensive and sophisticated experimental steps or even long reaction or sample preparation times. High-performance chromatography coupled with mass spectrometry (HPLC/MS) methods have also been reported and have emerged as a useful tool for allergen screening [ 25 , 26 ], but these analyses require complex and expensive equipment. The development of rapid, sensitive, and low-cost analytical methods for the detection and quantification of tropomyosin has therefore become a necessity.…”