Research On Receptor And Second Receptor For Human Adenovirus Type 55 Infection Of Cells

Human adenovirus type 55(Ad55)belongs to B subgroup adenovirus.It is produced by recombinant human adenovirus type 11 and human adenovirus type 14.It is highly pathogenic and can cause pneumonia even death.However,there is no effective strategy to treat Ad55 infection.More importantly,there is less research on the virology characteristics of Ad55,and the mechanism of its invasion of host cells is not clear.In the early stage,our laboratory found that the cluster of differentiation 46(CD46)and Desmoglein 2(DSG2)were the receptors for Ad55 infection,but it was also speculated that there might be a second receptor.Thus the problems have arisen: 1.Which receptor does Ad55 use to infect cells? 2.Is intergrin the second receptor for Ad55 infection?In this study,we found that Ad55 infected cells could be blocked by human adenovirus type 55 Fiber Knob.And to verify the receptor of Ad55,we constructed two plasmids that express soluble CD46 and soluble DSG2.Functional block experiment by pre-incubation with soluble receptor protein of human adenovirus with Ad55,we found that Ad55 infection could be blocked by soluble CD46 and soluble DSG2,indicating that the two proteins are receptors for Ad55.To verify the receptor of Ad55,after we used Ad5-CD46 and Ad5-DSG2 to infect Hepa1-6 cells,Ad55 could infect the cells.The association and dissociation constants between Ad55 Fiber Knob and soluble CD46 or soluble DSG2 was analyzed by surface plasmon resonance experiment.It was found that the association and dissociation constants between Ad55 Fiber Knob and soluble DSG2 was lower than those of soluble CD46.Meanwhile,in the experiment of Ad55 second receptor,we found that when the interference RNA interfered the expression of integrin alpha 5,beta 1 and beta 5,the infection of Ad55 would be resisted,indicating that integrin alpha 5 beta 1 and integrin alpha 5 beta 5 are the second receptors for Ad55 entry into cells.