Study On Toxicity Of Ricin To Primary Lung Tissue Macrophages In Mice

Toxicology is the subject on researching the toxic effects and the mechanism ofexogenous factors’ toxicity to organism. It’s usually interdisciplinary with pathology,physiology and pharmacology of which theories and techniques can be applied to explain thetoxic reaction. Toxicology takes organism as researching object and describes the pathologicalchanges, immune response and action mechanism for the qualitative and quantitative analysisof toxic effect and determining the toxicity level and safety range, hereby providing ascientific basis for future prevention and treatment. As the purpose of toxicology research is toprotect organism healthy and develop related-drug, toxicology is a branch of preventivemedicine. Ricin as highly toxic phytotoxin, is a researching hotspot, while its mechanism ofaction and some biological phenomena still cannot be explained.In advance of this study, mice model exposed to ricin aerosol had been constructed andwe obtained the respiratory system damage data and different expression protein of lungtissues. Our research is based on data at the animal level and further elaborates the damagemechanism of lung tissue at the cellular level. At first, extraction method of mouse primarypulmonary macrophages was created and activity of macrophages was identified, then infectedthe cell with ricin for50%inhibiting concentration and clinicopathologic analysis. Beyondthat cytokines quantization for immune level has been done by RT-qPCR and key proteinsrelated to ricin toxicity were found by two-dimensional gel electrophoresis and MALDI-TOF.The results indicate that the perfusion method could extract pulmonary macrophages withhigh purity and strong vitality and the IC50(half maximal inhibitory concentration) to ricin was1ng/mL based on the MTS analysis. Vacuoles, flocculent sediments can be observed in thecells and the nucleus becoming smaller under transmission electron microscope.Real-time quantitative PCR show that five inflammatory cytokines and two chemokinesall had a high expression, the IL-1had a thousand fold expressed with the RQ1315.6and theRQ value of IL-6and CXCL2were272.1and467.0respectively, their expression has a verysignificant differences comparing with control group. While the RQ of other four cytokines(IL-6,TNF-α,CCL2,INF-γ) is20.7,17.4,12.3and6.9respectively and also had asignificant differences comparing with control. And13protein spots had been picked up after two-dimensional gel electrophoresis and MALDI-TOF, they were Proteasome subunit,T-complex protein, Peroxiredoxin, Alpha-enolase, Protein disulfide-isomerase,Fructose-bisphosphatealdolase A, Actin, Serum albumi, Phosphoglycerate kinase, Elongationfactor2and Pyruvate kinase isozymes. According to the literature research and biologicalfunction analysis,4spots having the highest correlation with ricin would be study firstly andthey had the relation with glycolysis, redox, cytoskeleton and misfolding protein degradation.These proteins could provide the direction and breakthrough point for researching thesignaling pathway and key protein related to ricin toxicity. Above all, our study could supplydata about existed damage mechanism and toxic effect of ricin and explore new direction forvaccines and therapeutic drugs developing.