IMMUNOLOGICAL DIFFERENTIATION OF HUMAN TISSUE-NONSPECIFIC TYPE ALKALINE PHOSPHATASES BY A MONOCLONAL ANTIBODY TO THE ENZYME OF HUMAN OSTEOBLAST-LIKE CELLS

Monoclonal antibodies against alkaline phosphatase [ALP; ortho-phosphoric monoester phosphohydrolase, alkaline optimum, EC 3.1.3.1.] of cultured human osteoblast-like cells (HBC) were raised in mice. Immuno-reactions of tissue-nonspecific type ALP from human bone, dental pulp, liver and kidney as well as intestinal and placental types to the monoclonal antibodies were compared by a dot immunoassay and ELISA. One clone was able to recognize antigenic differences among tissue-nonspecific type ALPs in addition to intestinal and placental ALPs; it reacted favorably with ALPs from HBC, human bone, kidney and dental pulp, but not with human liver enzyme. Similarly, the antibody immunoreacted with bone-derived ALP but not with liver-derived enzyme present in human serum.The present monoclonal antibody preparation can be utilized in basic studies as well as in clinical laboratory tests to distinguish minor heterogeneity among human Al Ps

VOLUNTARY EXERCISE INCREASES OSTEOGENETIC ACTIVITY IN RAT BONES

The purpose of this study was to investigate the effect of voluntary exercise on osteoinductive activity in rat bone. Sprague-Dawley male and female rats were allowed to exercise freely by running on a treadmill or kept as controls without exercise for 53 days. Decalcified humeral diaphyses from experimental and control rats were implanted intraperitonealy into host rats and harvested after 33 days. A significant increase in bone formation was confirmed in the implanted bone matrices from the running group in comparison with those from control animals by soft X-ray photography and determination of alkaline phosphatase activity and mineral content. Alkaline phosphatase activity in bone and serum was increased by exercise in both male and female animals. The results suggest that osteoinductive activity in the bone was probably due to increased levels of bone morphogenetic protein following voluntary exercise

PROPERTIES OF ALKALINE PHOSPHATASE IN THE GINGIVAL CREVICULAR FLUID

The isoenzymic properties of the alkaline phosphatase (ALP) of the gingival crevicular fluid (GCF) were investigated and compared with those in other cells, such as human polymorphonuclear leukocytes (PMNs), and human periodontal ligament cells (PDLs), and with those of three species of periodontopathic bacteria: Porphyrnmonas gingivalis 381 (P. gi.ngivalis), Prevotella inteγmedia ATCC25611 (P. intermedia), and Capnocytophaga sputigena ATCC33123 (C. sputigena). The biochemical properties of the isoenzymes were analyzed by the following methods: enzyme assays, inhibition pattern using three chemical inhibitors, 4 to 20% gradient polyacrylamide gel electrophoresis, thermostability, immunological specificity, and phosphatidylinositol-specific phospholipase C (PIPLC) treatment. The inhibition experiment showed that ALP of the PMNs and PDLs possessed almost the same enzymatic properties of tissue-nonspecific ALP (bone/liver/kidney; TNSALP), and the ALP of the three species of periodontopathic bacteria possessed specific properties that were different from those of TNSALP, intestinal, or placental ALP. The ALP of the GCF was only slightly susceptible to levamisole (1 mM), L-phenylalanine (20 rnM), and SDS ( 1%). An electrophoresis thermostability test demonstrated that the enzyme activity of the GCF was separated into one or two bands. The main heat-labile slow band contained the phosphatidylinositol (Pl)-moiety-anchored ALP and possessed immunological specificity against anti-bone type ALP. The minor fast band was heat stable and showed mobility similar to that in P. gi.ngi.valis. These results indicated that the ALP of the GCF consisted of several ALP isoenzyme types whose possible origins are considered to be derived from phosphatidylinositol (Pl) anchored ALP and periodontopathic bacterial ALP. The quantitative isoenzyme analysis of ALP in GCF may elucidate the mechanism of the disease activity of periodontitis