title: A Fluorescence-Labeled Heptapeptide, (FITC)KP6, as an Efficient Probe for the Specific Detection of Oxidized and Minimally Modified Low-Density Lipoprotein.
abstract: Two oxidized forms of low-density lipoprotein (LDL), oxidized LDL (ox-LDL) and minimally modified LDL (MM-LDL), are believed to play a major role in the pathogenesis of atherosclerosis. Recently, we reported that a heptapeptide (Lys-Trp-Tyr-Lys-Asp-Gly-Asp, KP6) coupled through the ε-amino group of N-terminus Lys to fluorescein isothiocyanate, (FITC)KP6, bound to ox-LDL but not to LDL. In the present study, we investigated whether (FITC)KP6 could be used as a fluorescent probe for the specific detection of MM-LDL and ox-LDL. Results from polyacrylamide gel electrophoresis and surface plasmon resonance proved that (FITC)KP6 could efficiently bind to MM-LDL as well as ox-LDL in a dose-dependent manner and with high affinity (K D = 3.16 and 3.54 ng/mL protein for MM-LDL and ox-LDL, respectively). (FITC) KP6 bound to lysophosphatidylcholine and oxidized phosphatidylcholine, both present abundantly in ox-LDL and MM-LDL, respectively. In vitro, (FITC)KP6 was detected on the surface and/or in the cytosol of human THP-1-derived macrophages incubated with ox-LDL and MM-LDL, but not LDL. These results suggest that (FITC)KP6 could be an efficient fluorescent probe for the specific detection of ox-LDL and MM-LDL and can therefore contribute to the identification, diagnosis, prevention, and treatment of atherosclerosis.
authors.affiliation: Faculty of Pharmacy, Iwaki Meisei University, 5-5-1, Chuodai-Iino, Iwaki, Fukushima, 970-8551, Japan. a-sato@iwakimu.ac.jp.
authors.forename: Akira
authors.initials: A
authors.lastname: Sato
authors.affiliation: Faculty of Pharmacy, Iwaki Meisei University, 5-5-1, Chuodai-Iino, Iwaki, Fukushima, 970-8551, Japan.
authors.forename: Chiemi
authors.initials: C
authors.lastname: Ueda
authors.affiliation: Faculty of Pharmacy, Iwaki Meisei University, 5-5-1, Chuodai-Iino, Iwaki, Fukushima, 970-8551, Japan.
authors.forename: Ryu
authors.initials: R
authors.lastname: Kimura
authors.affiliation: Faculty of Pharmacy, Iwaki Meisei University, 5-5-1, Chuodai-Iino, Iwaki, Fukushima, 970-8551, Japan.
authors.forename: Chisato
authors.initials: C
authors.lastname: Kobayashi
authors.affiliation: Faculty of Pharmacy, Iwaki Meisei University, 5-5-1, Chuodai-Iino, Iwaki, Fukushima, 970-8551, Japan.
authors.forename: Yoji
authors.initials: Y
authors.lastname: Yamazaki
authors.affiliation: Faculty of Pharmacy, Iwaki Meisei University, 5-5-1, Chuodai-Iino, Iwaki, Fukushima, 970-8551, Japan.
authors.forename: Keiichi
authors.initials: K
authors.lastname: Ebina
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D045744:Cell Line, Tumor; D005456:Fluorescent Dyes / Q000737:chemistry* / Q000378:metabolism*; D006801:Humans; D057230:Limit of Detection; D008077:Lipoproteins, LDL / Q000378:metabolism*; D008297:Male; D051379:Mice; D009842:Oligopeptides / Q000737:chemistry* / Q000378:metabolism*; D010743:Phospholipids / Q000378:metabolism; D058226:Plaque, Atherosclerotic / Q000378:metabolism
chemical_list: D005456:Fluorescent Dyes; D008077:Lipoproteins, LDL; D009842:Oligopeptides; D010743:Phospholipids; C099252:oxidized low density lipoprotein
keywords: Atherosclerosis; Fluorescence; Heptapeptide; Minimally modified LDL; Oxidized LDL; Probe