Circulating tumor cells (CTCs) are tumor cells that are shed from the tumor and circulate in the blood of cancer patients, potentially forming distant metastasis. Knowledge gained from analyzing CTCs can be used for prognosis, monitoring of treatments and predict their response in patients. CTCs can be detected in peripheral blood using a simple and convenient liquid biopsy.
As a qualified RareCyte® service provider, CellCarta produces longitudinal analysis of liquid biopsy samples for clinical research partners, which include information on CTC numbers and phenotypic characterization, with a possibility to perform cell-free DNA analysis. A complete data-management pipeline is set-up to cope with the high-dimensional images (~35GB per slide), implementing an automated archiving flow.
CTCs are challenging to identify and characterize. CellCarta selected the RareCyte® platform (CyteFinder®) to provide a highly sensitive, accurate, simple, and scalable workflow from liquid biopsy to CTC enumeration and blood-based biomarker identification.
Our team of experts take the utmost care in preparing slides from whole blood samples. CellCarta’s quality workflow from sample collection to scanner and imaging analysis leads to reduced sample volume requirements.
Features of our slide preparation process include:
The prepared smears on slides are then stained using automated staining instruments (Leica Bond RX and Ventana Discovery Ultra), scanned and analyzed by an imaging scientist.
CTC clusters are immunophenotyped by automated IF assays, using four canonical markers: DAPI – a nuclear dye for the identification of CTCs, CD45 – the white blood cells (WBC) exclusion marker, EpCAM and cytokeratin (CK) – the epithelial CTC markers. Up to two investigational biomarkers can be simultaneously assessed on the identiﬁed CTCs for in-depth phenotypic characterization, making it possible to not only visually identify and count CTCs but also monitor biomarker expression over time.
Stained slides are scanned with the platform’s automated ﬂuorescence scanning microscope (CyteFinder® HT) and analyzed with integrated image analysis software that automatically analyzes the images to ﬁnd and score CTC candidates. Candidate objects are ranked by a machine-learning model and classiﬁcation of a cell as a CTC requires reviewer conﬁrmation.
The combination of reproducible automated immunostaining and CTC analyses using algorithms enable the use of RareCyte® in large scale clinical trials.
We are an active participant in the Innovative Medicines Initiative (IMI) CANCER-ID multicenter ring trial to define standards in blood-based biomarkers, all together making us a pioneer in integrating single-cell data in academic and clinical settings.