Different Toxicity Of Cadmium Telluride,Silicon,and Carbon Nanomaterials Against Hemocytes In Bombyx Mori

Nanomaterials are widely used in biological imaging,drug-targeted transport studies and tumor therapy due to their advantages.So the biological toxicity of nanomaterials is coming to the forefront.Due to lack of the platform to uniformly assess the toxicity of nanomaterials,these experimental data cannot be compared equitably.Moreover,some of the results are contradictory.In this paper,we use the silkworm hemolymph system which has been widely used in our laboratory.Hemolymph were exposed directly to CdTe QDs,C-NCDs and SiNPs which have significantly different toxicity on cells and animals by the method of vasodilator injection.The different mechanisms of programmed cell death caused by different nanomaterials in vivo were discussed.The main results are as follows: Different nanomaterials caused different immune responses in silkworm haemolymphWhen the silkworm haemolymph were exposed to CdTe QDs,C-NCDs or SiNPs,the characteristic fluorescence of the three nanomaterials showed that they were able to enter the hemocytes.The results of the qPCR have proved that nanomaterials induced significant difference in the pattern and expression level of the genes related to immune.C-NCDs rapidly induced the up-regulation of antimicrobial peptides in the haemolymph and cause phagocytosis of hemocytes through the p38-MAPK pathway,after that the hemolymph system returned to normal.All results showed that C-NCDs displayed weak hemocytes toxicity.The response speed of antimicrobial peptides and p38-MAPK pathway induced by SiNPs or CdTe QDs were later than that induced by C-NCDs,but the response level was higher,and the phagocytosis of hemocytes was stronger.On the other hand,the mechanism induced by SiNPs might be related to the phagocytosis of the hemocytes which is independent of the p38-MAPK pathway,while CdTe QDs triggered the innate immune response of hemocytes mainly through p38-MAPK pathway.The results indicated that different nanomaterials triggered different level and speed of immune response.Different nanomaterials caused different mechanisms of hemocytes cytotoxicityResults of classified hemocytes count in the hemolymph,and the qualitative analysis and related mechanisms exploration of the programmed cell death indicated that three nanomaterials investigated in this study induced significantly different effects.CdTe QDs significantly reduced the number of hemocytes not only by apoptosis which was induced by intracellular lysosomal increase and lysosomal membrane rupture,but also by necrosis induced by the damage of hemocytes membrane structure.The influences of SiNPs,which was reduction of hemocytes number,were mainly through the apoptosis induced by released calcium ions,via the endoplasmic reticulum stress,and through a small amount of autophagy.Although apoptosis and necrosis in hemocytes induced by C-NCDs was not detected,the autophagy happened,whose level was time-dependent.The number of hemocytes did not affected by C-NCDs in Bombyx mori.