TY - JOUR
T1 - Enhancement of drug delivery to bone
T2 - Characterization of human tissue-nonspecific alkaline phosphatase tagged with an acidic oligopeptide
AU - Nishioka, Tatsuo
AU - Tomatsu, Shunji
AU - Gutierrez, Monica A.
AU - Miyamoto, Ken ichi
AU - Trandafirescu, Georgeta G.
AU - Lopez, Patricia L.C.
AU - Grubb, Jeffrey H.
AU - Kanai, Rie
AU - Kobayashi, Hironori
AU - Yamaguchi, Seiji
AU - Gottesman, Gary S.
AU - Cahill, Richard
AU - Noguchi, Akihiko
AU - Sly, William S.
N1 - Funding Information:
This work was supported by grants from the Austrian Research Society for Mucopolysaccharidoses and Related Diseases, German MPS, International Morquio Organization, Italian MPS Society, the Jacob Randall Foundation, the Bennett Foundation, and National Institutes of Health Grant GM34182 to W.S.S.
PY - 2006/7
Y1 - 2006/7
N2 - Hypophosphatasia is caused by deficiency of activity of the tissue-nonspecific alkaline phosphatase (TNSALP), resulting in a defect of bone mineralization. Enzyme replacement therapy (ERT) with partially purified plasma enzyme was attempted but with little clinical improvement. Attaining clinical effectiveness with ERT for hypophosphatasia may require delivering functional TNSALP enzyme to bone. We tagged the C-terminal-anchorless TNSALP enzyme with an acidic oligopeptide (a six or eight residue stretch of l-Asp), and compared the biochemical properties of the purified tagged and untagged enzymes derived from Chinese hamster ovary cell lines. The specific activities of the purified enzymes tagged with the acidic oligopeptide were the same as the untagged enzyme. In vitro affinity experiments showed the tagged enzymes had 30-fold higher affinity for hydroxyapatite than the untagged enzyme. Lectin affinity chromatography for carbohydrate structure showed little difference among the three enzymes. Biodistribution pattern from single infusion of the fluorescence-labeled enzymes into mice showed delayed clearance from the plasma up to 18 h post infusion and the amount of tagged enzyme retained in bone was 4-fold greater than that of the untagged enzyme. In vitro mineralization assays with the bone marrow from a hypophosphatasia patient using each of the three enzymes in the presence of high concentrations of pyrophosphate provided evidence of bone mineralization. These results show the anchorless enzymes tagged with an acidic oligopeptide are delivered efficiently to bone and function bioactively in bone mineralization, at least in vitro. They suggest potential advantages for use of these tagged enzymes in ERT for hypophosphatasia, which should be explored.
AB - Hypophosphatasia is caused by deficiency of activity of the tissue-nonspecific alkaline phosphatase (TNSALP), resulting in a defect of bone mineralization. Enzyme replacement therapy (ERT) with partially purified plasma enzyme was attempted but with little clinical improvement. Attaining clinical effectiveness with ERT for hypophosphatasia may require delivering functional TNSALP enzyme to bone. We tagged the C-terminal-anchorless TNSALP enzyme with an acidic oligopeptide (a six or eight residue stretch of l-Asp), and compared the biochemical properties of the purified tagged and untagged enzymes derived from Chinese hamster ovary cell lines. The specific activities of the purified enzymes tagged with the acidic oligopeptide were the same as the untagged enzyme. In vitro affinity experiments showed the tagged enzymes had 30-fold higher affinity for hydroxyapatite than the untagged enzyme. Lectin affinity chromatography for carbohydrate structure showed little difference among the three enzymes. Biodistribution pattern from single infusion of the fluorescence-labeled enzymes into mice showed delayed clearance from the plasma up to 18 h post infusion and the amount of tagged enzyme retained in bone was 4-fold greater than that of the untagged enzyme. In vitro mineralization assays with the bone marrow from a hypophosphatasia patient using each of the three enzymes in the presence of high concentrations of pyrophosphate provided evidence of bone mineralization. These results show the anchorless enzymes tagged with an acidic oligopeptide are delivered efficiently to bone and function bioactively in bone mineralization, at least in vitro. They suggest potential advantages for use of these tagged enzymes in ERT for hypophosphatasia, which should be explored.
KW - Alkaline phosphatase
KW - Drug delivery system
KW - Hypophosphatasia
UR - http://www.scopus.com/inward/record.url?scp=33745497185&partnerID=8YFLogxK
U2 - 10.1016/j.ymgme.2006.02.012
DO - 10.1016/j.ymgme.2006.02.012
M3 - Article
C2 - 16616566
AN - SCOPUS:33745497185
SN - 1096-7192
VL - 88
SP - 244
EP - 255
JO - Molecular genetics and metabolism
JF - Molecular genetics and metabolism
IS - 3
ER -