Comparison of cellular binding and uptake of antisense phosphodiester, phosphorothioate, and mixed phosphorothioate and methylphosphonate oligonucleotides.

摘要: The effects of phosphorothioate (S-oligonucleotide) or terminal phosphorothioate-phosphodiester (S-O-oligonucleotides) methylphosphonate-phosphodiester (MP-O-oligonucleotides) modifications on mouse spleen cell surface binding, uptake, and degradation were studied using fluorescein (FITC)-conjugated oligonucleotides. S-oligonucleotides had the highest binding followed by S-O-, O-, MP-O-oligonucleotides. Competition studies indicated that have an increased affinity for membrane oligonucleotide sites, because they could completely block O-oligonucleotide at a molar ratio just 0.1. Uptake all oligonucleotides was higher in B cells than T stimulation with B-cell mitogen, lipopolysaccharide. Although our been purified conventional techniques to eliminate dead cells, there remained about 5% dying, as determined flow cytometry propidium iodide staining. Of note, association approximately 50-fold greater living cells. Confocal microscopy confirmed intracellular, little nuclear uptake 4 h. While extensive intracellular O-oligonucleotides apparent h, no detectable S-, S-O,