Isolated Peptides Binding Specifically To Exsomtized Human Osteosarcoma Blood Vessuels From Peptide Library

Objective To select the peptides binding specifically to human osteosacoma blood vessuels using phage display technology,and provide useful information for the targeted chemotherapy of osteosacoma.Methods An hi vivo biopanning model was established simulating the Langendorff perfusion apparatus,with exsomatized human osteosacoma blood vessuels as target,a 12-meres phage display peptide library was subtract biopanned. The sequences of some positive phages and their corresponding peptides were deduced according to their DNA sequences,and phages distribution was analyzed in vivo by immunohistochemistry.Results We successfully established an hi vivo biopanning model simulating the Langendorff perfusion apparatus,with both exsomatized human osteosacoma blood vessuels and normal tissue,and the normal tissue only as control,a 12-meres phage display peptide library was biopanned. After 4 rounds selection,13 random positive clones were sampled to sequencing,so the sequences of positive phages and their corresponding peptides were obtained,the comparatively conservative sequence was found,the motif is RLTR. The positive phages are sampled to analyze phage distribution hi vivo by immunohistochemistry. They all bind to osteosacoma blood vessuels but not to normal tissues or mammary cancer.Conclusion The peptides capable of homing specifically to exsomatizedhuman osteosacoma blood vessuels were isolated,the motif is RLTR,which may be useful for further study of the targeted chemotherapy of osteosacoma.