Preliminary Study for Identification of Calcium-Binding Proteins in the Serum in Various Metabolic Bone Disorders
Preliminary Study for Identification of Calcium-Binding Proteins in the Serum in Various Metabolic Bone Disorders
The purpose of this study is to determine whether the serum levels of certain calcium-binding
 proteins may be helpful in the diagnosis and management of metabolic bone diseases.
Osteoporosis is an important and costly health issue. The diagnosis of the disease is based
 on measurement of bone mineral density or the occurrence of characteristic fractures.
 Currently it is not possible to predict fractures in individual patients, and the ability to
 monitor the response to treatment is limited as well.

 We have synthesized and characterized a novel photoreactive Ca2+-analog reagent, Azido
 ruthenium (AzRu) that binds covalently to Ca2+-binding sites in proteins. The specificity of
 AzRu for Ca2+-binding proteins, its photoactivation and its radioactive labeling pave the way
 for a wide use of AzRu as a powerful tool to assess Ca2+-dependent cellular processes, both
 in vitro and in vivo. Using radiolabeled AzRu, it will be possible to identify Ca2+-binding
 proteins in a biological sample such as whole cell, isolated mitochondria, ER or other
 protein containing fractions. Protein bound [103Ru]AzRu in biological sample can be separated
 by SDS gel electrophoresis, followed by Coomassie staining and exposure of the dried gel to
 X-ray film (autoradiography). This allows the identification of the [103Ru] radiolabeled
 proteins. The labeled protein bands can be cut from the gel and subjected to MALADI-TOF
 analysis and the identity of the protein can be determined by a sequence homology search.

 These would allow detection of Ca2+-binding proteins in the serum of various diseases and
 disorders, potentially leading to identification of novel biomarkers for disease diagnostics.

 We would like to use blood samples to carry out the procedure described above for
 identification of Ca2+ binding proteins appearing or their level is increased in disease or
 under pathogenic conditions. Since Ca2+ binding proteins play an important role in bone
 metabolism, we chose to test their occurrence in the serum of patients with osteoporosis and
 other metabolic bone diseases.
Inclusion Criteria:

 -  Clinical diagnosis of a metabolic bone disorder

 Exclusion Criteria:

 -  none