Velcura’s Technologies: Velcura can grow human bone outside the body (ex vivo) using a rapid (7 – 10 days) and reliable method (Figure 1). From this, we discover therapeutic targets for bone disorders such as osteoporosis, bone cancer, bone fractures, and other diseases of bone. Velcura applies rapid molecular and biological bone assays, and bioinformatic analysis to the systematic discovery of the genes, biological pathways, and drug candidates that accelerate bone formation. With this approach, Velcura can rapidly identify and validate new therapeutic targets.

Ex Vivo Bone Formation. Our ability to grow human bone cells allows the careful dissection of the molecular control of bone formation. Both bone precursor cells, and mature bone cells are isolated from human bone, and used in bone-forming assays, bone cell functional assays, and gene and proteinexpression assays. Thus, the effects of small molecules, biologicals, or genes are readily and rapidly determined.

Our recent advances in technology have made Velcura the industry leader in discovering molecular targets for stimulating bone formation. This is due to our strong patent position that makes us the sole source for the technology of forming human bone outside the body. Velcura thus holds the key to efficient discovery of bone growth-promoting therapeutics:

• The only in vitro, cell-based bone formation assay for human bone growth-promoting substances.
• Facilitation of both drug discovery and identification of critical molecular targets for bone disease.
• Multiple patents with broad claims; exclusively licensed to Velcura.

Human Bone Therapy System (HBTS). Velcura has developed a high content, cell-based screening assay system to rapidly identify bone-active molecules, using human bone cells as a target. As well, a number of reproducible, highly sensitive assays are used to determine whether bone-active molecules affect bone cell enzymatic expression, maturational characteristics, and proliferation capacity. Velcura has pioneered the use of fluorescence-activated cell sorting as a means for multi-parameter analysis of bone cells in this regard.

Bone Gene Expression Analysis. The company is constructing and populating a number of databases that collect and track information on the changes in gene expression during bone formation. These databases include information on genetic alterations occurring in normal bone formation, bone injury and repair, and a number of bone diseases including bone cancer, osteoporosis, and Paget's Disease. Each database will consist of multiple individual gene expression profiles for each medical condition, thus allowing simultaneous identification of individual variations as well as composites. As part of this program, Velcura is developing an OsteoChip™ (expected completion 1st quarter 2004) that contains all genes differentially modulated during human bone formation. This approach will rapidly accelerate the drug discovery process for our strategic partners and us.

Velcura’s current data indicate that there are 1100 differentially regulated genes identified as being significantly modulated during human bone formation (Figure 2). That is, genes that show average to low expression in control cells are increased in the induced cells. Further Bioinformatic analysis identified a number highly-modulated genes of interest in bone formation, covering a wide array of physiologically relevant proteins (Figure 3.), including transcription factors, Homeobox genes, Helix-loop-helix proteins, etc. These genes are now being evaluated as potential therapeutics targets that are important to bone formation.

Bone Protein Expression Analysis. In order to confirm and extend its gene expression analysis Velcura has developed a system to evaluate protein changes during human bone formation. This field is referred to as Proteomics - the analysis of global protein changes in a cell. Importantly, we are using a combination of 2-dimensional gel electrophoresis (2-DGE) and mass-spectrometry to identify differentially modulated proteins (Figure 4). We have further reduced the complexity of this system by fractionating human bone cells into membrane, cytoplasm, and nuclear components. Currently, Velcura is evaluating nuclear fractions of stimulated human bone cells, and has detected a number of signaling proteins that are up-regulated, as well as a number that are new or newly translocated in the nucleus of cells undergoing bone formation. Next, these protein-spots are analyzed by mass-spectrometry.

High-Throughput Bioinformatics. Velcura's Bioinformatics Program is developing sophisticated computer analysis tools and laboratory information management programs to accelerate our development times. In connection with our gene and protein analyses, our bioinformatics capabilities allow a rapid, high-content understanding of bone formation at the molecular level.