Peptide-derivatized shell-cross-linked nanoparticles evaluated.

2004 OCT 6 - (NewsRx.com & NewsRx.net) -- Scientists have completed a biocompatibility evaluation of peptide-derivatized shell-cross-linked nanoparticles.

"The conjugation of the protein transduction domain (PTD) from the HIV-1 Tat protein to shell crosslinked (SCK) nanoparticles is a method to facilitate cell surface binding and transduction. In a previous report, the preparation, derivatization, and characterization of peptide-functionalized SCK nanoparticles were reported in detail. Following assembly, the constructs were evaluated in vitro and in vivo to obtain a preliminary biocompatibility assessment," investigators in the United States report.

"The effects of SCK exposure on cell viability were evaluated using a metabolic 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) and a fluorescent apoptosis assay," said Matthew L. Becker and colleagues at Washington University in St. Louis. "Furthermore, stages of apoptosis were quantified by flow cytometry. Although higher levels of peptide functionalization resulted in decreased metabolic function as measured by MTT assay, significant apoptosis was not observed below 500 mg/L for all the samples."

"To evaluate the potential immunogenic response of the peptide-derivatized constructs, a real-time polymerase chain reaction (RT-PCR) system that allows for the in vitro analysis and quantification of the cellular inflammatory responses tumor necrosis factor alpha (TNF-alpha) and interleukin-1 beta (IL1-beta) was utilized," stated Becker and his collaborators. "The inflammatory response to the peptide-functionalized SCK ...