Technology

Core Technology

The "Combination-of-Combinations-Principle" (COCP)

AdnaGen's system makes use of the very sensitive RT-PCR (reverse transcriptase - polymerase chain reaction); the advantage of this approach over current methods is the sensitive detection of disseminated tumor cells in patients' blood which allows the analysis of tumor associated gene expression. AdnaGen's two-step "Combination-of-Combinations-Principle" involves (1) cell isolation, whereby tumor cells are enriched by an antibody-mix linked to magnetic particles and mRNA is isolated from the selected tumor cells, and (2) molecular biological detection and analysis, whereby the isolated mRNA is transcribed into cDNA and a multiplex PCR is carried out for the analysis of tumor associated gene expression. Due to the combination of different selection and tumor markers, both the heterogeneity of the tumor cells and possible individual or therapy induced deviations in the expression patterns are taken into account.

Higher sensitivity and specificity

Using its proprietary technology, AdnaGen offers a comprehensive patented solution for the detection of circulating tumor cells. The Company's Tumor Diagnostics are complete kits consisting of reagents for immunomagnetic selection, mRNA isolation and multiplex RT-PCR, and can be performed on standard technology platforms. The products have high analytical sensitivity (2 cells in 5 ml blood) and high specificity (greater 90%) achieved through the combination of multi-marker tumor cell enrichment and multiplex gene expression profiling.

A. Cell isolation

In a first step, tumor cells are enriched from peripheral blood of cancer patients by means of antibody-linked magnetic particles in vitro. The antibody combination has been particularly adopted to the respective type of tumor. Subsequently, the mRNA is isolated from the selected tumor cells.

Molecular biological detection of tumor associated markers

B. Molecular biological detection

The isolated mRNA is transcribed into cDNA and a multiplex PCR for the detection of tumor associated gene expression is carried out. Due to the combination of different selection and tumor markers, both the heterogeneity of the tumor cells and possible individual or therapy induced deviations in the expression patterns are taken into account.

This example shows 11 breast cancer patients that already have clinically confirmed metastases. The expression of only one of the molecular markers indicates a positive finding of circulating tumor cells in the bloodstream. All these metastatic cases yielded positive results. Only patient 3 did not show an expression of tumor markers, which was due to a high dose chemotherapy at this time.