Study On Cell Bioassay For Paralytic Shellfish Poisoning

Objective: Paralytic shellfish poisoning(PSP) is known as neural paralysis by in-take of shellfish with poisons by mistake. PSP is widely distributed in the oceans all over the world. PSP is characterized with strong toxicity and high mortality. PSP functioned as inhibitor of sodium channel inside human body. It targets to cardiovascular and neuron system with high specifity. There is no effective antidote of PSP so far.Many testing methods for PSP were established, however costs of these methods are still very high. Thus there is an urgent need for a PSP testing method with high sensitivity and low cost.Methods: This study aims to establish an N2 a cell based method to test PSP in shellfish with high sensitivity and low cost. Data of poisoning incidents by in-taking of PSP within 15 years were collected and analyzed.The epidemiological distribution of PSP poisoning was studied and discussed. 2D-DIGE was applied to screen the differentiated proteins induced by PSP in N2 a cells the key proteins were then further validated by Western-blot analysis and ELISA. The testing method is based on the validated proteins and specifity and sensitivity of this method was evaluated.Results: There was 21 references used in this study, a total of 131 PSP poisoning cases were reported with 889 people involved and 69 weredead, the mortality rate was 7.76%.130 cases were in the coastal area. 3cases were reported in the first quarter, 67 in the second quarter, 59 in the third quarter and 2 in the fourth quarter. 124 cases were caused by Nassariidae, including 732 patients.Proteomic study revealed that STX induced 9 proteins abnormally altered in N2 a cells. The expression of14-3-3, α-enolase and cofilin-2 were validated by ELISA. The expression of α-enolase was positive correlated with the concentration of STX, and the results were consisted with classic methods for testing PSP.Conclusion: PSP poisoning cases were mainly distributed at the coastal area in the second and third quarter of the year. 14-3-3 and α-enolase were up-regulated and cofilin-2 was down-regulated after the treatment of STX in N2 a cells. The expression of α-enolase was positively correlated with STX concentration in the range of 1-10nmol/L. Thus the limitation of detection(LOD) of this N2 a cell based method is 1nmol/L which is0.299μg/100 g.