BioMag-SELEX As A Method For DNA Aptamer Against Cyclosporin A Selection

Cyclosporin A,a cyclic undecapeptide with 11 amino acids of fungal origin,is a potent immunosuppressive drug that is effctive in combatting tissue rejection following organ transplantation.It has greatly improved allograft survival in kidney,liver,and heart transplants.Meanwhile,the use of cyclosporin is associated with serious toxic side effects,primarily nephrotoxicity and hepatotoxicity for the parent drug or of the metabolites.So it is vital to monitor cyclosporine concentration in whole blood regularly.SELEX(Systematic Evolution of Ligands by Exponential Enrichment),is also known as a new selection technique in vitro.Aptamer,which is screened from the large random nucleic acids libraries by SELEX technique, is oligonucleotide that bind to targets with high affinity and specificity.As aptamer is resembled with antibody but superior to antibody for having a large number of target molecules,high affinity and specificity, stability and ease of production,regeneration.Aptamer has promising applications prospect in clinical therapy and laboratory diagnosis.This study aim to screen the aptamer with high affinity and specificity for cyclosporin A and set a base for establishing relative easy and quick laboratory detection methods.We conjugated the cyclosporin A to tosylactivated magnetic beads covalently at first.A synthesized 78 nt single stranded DNA(ssDNA)random library containing 35 ranodm sequences flanked by invariant primer was subjected to 10 rounds of selection against cyclosporin A-conjugated magnetic beads by Bio-Mag SELEX method,which...