Led By Passionate Experts

Led By Passionate Experts

Sensitivity, Specificity & Accuracy. For
Better CAR-T Therapy

Sensitivity, Specificity & Accuracy.
For Better CAR-T Therapy

excelling in our industry

Who We Are

Cytoart Inc. is a biotechnology company committed to developing and providing advanced cell therapy detection products and integrated solutions. Our primary focus is on offering precise and effective anti-idiotypic platform for clinicians and researchers in the innovative domain of cell therapy.

the highest sensitivity for CAR T-Cell detection in the market

Our Products

At CytoArt, we are proud to introduce a groundbreaking leap in the realm of immunotherapy and diagnostic research: the first commercially available anti-idiotypic CAR detection antibodies. Our pioneering product stands at the forefront of scientific innovation, offering an unparalleled level of specificity and sensitivity that sets a new standard in the industry.

Our antibodies are meticulously engineered to excel in a diverse range of applications, including Flow Cytometry and PCR, catering to the critical needs of Ligand Binding, Pharmacokinetics (PK), Anti-Drug Antibody (ADA)/Neutralizing Antibody (Nab) Analysis assays. This versatility extends to the domain of long-term in-vivo CAR monitoring, underscoring our commitment to supporting the ongoing needs of both research and clinical diagnostics.

At CytoArt, we believe in empowering our clients with the tools they need to push the boundaries of what’s possible in cancer treatment and diagnostic methodologies. Our products are not just tools; they are gateways to new discoveries and innovations that will lead the way in the fight against disease.

your questions, Answered


Have some questions? We’ve compiled a list of the most commonly asked questions around our products.

Advancements in cellular therapies have paved the way for treatments that genetically modify a patient’s T cells—critical components of the immune system—to target and destroy malignant cells. This process involves extracting T cells from the patient’s blood and engineering them in a lab to express a chimeric antigen receptor (CAR). These CAR cells are designed to latch onto a specific protein found on the malignant cells. These CAR cells are then multiplied in large quantities and administered back to the patient through an infusion. This innovative approach, known as CAR T-cell therapy, is currently under investigation for its potential to treat various types of cancer.

To Learn more of clinical breakthroughs, check Emily Whitehead’s amazing cancer fight story with CAR T-cell therapy here.

CAR T-cell therapy utilizes a complex structure that integrates both an extracellular domain responsible for binding to antigens on the surface of target cells, and an intracellular domain for signal transmission. The outer segment of the CAR is crafted from the single-chain variable fragment (scFv) of a monoclonal antibody, enabling precise recognition and attachment to specific antigens on the cancer cell’s surface. This is connected through a hinge and transmembrane region to the intracellular portion, which contains a CD3zeta chain from the T cell receptor (TCR) and costimulatory signals. When the CAR T cells engage with their target antigen via the scFv, the intracellular domain relays activation signals to the T cell. This activation triggers the T cell to release cytotoxic substances like perforin, granzymes, and interferons, leading to the destruction of the cancer cell.

In 2018, the FDA granted approval to two CAR T-cell therapies: Novartis’s Kymriah and Gilead’s Yescarta. Both treatments target CD19-positive B-cell tumors and utilize similar antigen-binding region; the scFv, which is sourced from the FMC63 mouse monoclonal antibody.
Our R19M are fully compatible with these pioneering CAR T-cell therapies.

The creation of CAR-T cells involves inserting the CAR gene into T cells using either viral or non-viral methods. Once the CAR is present on the T cell membrane, the modified T cells gain the ability to identify and eliminate target cells. Consequently, precise identification of CAR-positive T cells is crucial for the quality assurance of CAR T-Cell therapies. It plays a vital role in determining the clinical dosage, overseeing the production process, and aiding in diagnosis.

Two primary methods exist for identifying CAR T cells: quantitative PCR (qPCR) for CAR gene-positive T cells and fluorescent activated cell sorting (FACS) for CAR protein-positive T cells.

  • Quantitative PCR is a common technique for detecting CAR gene-positive T cells, capable of identifying the CAR gene within the genome and determining its copy number. However, qPCR may not accurately reflect the presence of surface-expressing CAR T cells due to potential gene silencing. A significant limitation of qPCR is its inability to differentiate between CAR-positive T and B cells, raising concerns about the potential risks associated with treatment and recurrence due to CAR-positive B cells. Additionally, qPCR falls short in detecting multiple T cell surface markers simultaneously (such as CD4, CD8), which restricts its utility.
  • Fluorescent activated cell sorting (FACS), a form of flow cytometry, enables the separation of biological cells into different groups based on their specific light scattering and fluorescent properties. FACS can accurately measure the rate of CAR transfection and distinguish among CAR domains, including the CD19 antigen or anti-scFv antibodies that bind to CAR scFv; anti-Fab antibodies or Protein L targeting the light chains framework or hinge region. The detection of antigen-binding sites offers the highest specificity for assessing the CAR positive rate, making it an optimal choice for quality control and non-clinical research in CAR-T cell therapy products.

There are several reagents, including anti-mouse IgG (Fab’)2, Protein L, CD19/Fc, and mouse monoclonal antibody 136.20.1.

  • Among them, antimouse IgG (Fab’)2 and Protein L demonstrated poor specificity of anti-CD19 CAR, unable to distinguish different CARs generated from mouse antibodies.
  • The sensitivity of CD19/Fc for detecting anti-CD19 CAR is low, since the affinity of FMC63 scFv to CD19 is lower than the affinity of the intact antibody to CD19.
  • Antibody 136.20.1, binding to FMC63 scFv, shows great specificity. Its sensitivity is close to 0.1%, that is, one anti-CD19 CAR positive cell is detected in 1,000 cells. However, when applied to clinical assistant diagnosis, the sensitivity is still low.
  • R19M(patent pending, developed by Cytoart)is a high affinity rabbit monoclonal antibody specifically binding to the anti-CD19 scFv that was derived from the FMC63. Its robust specificity and sensitivity allows this antibody to be a perfect tool for flow cytometry and other immunostaining applications.
  • R19P, our new ultra-high affinity rabbit anti-mouse polyclonal antibody, push the detection limit to 1/100,000, which means we can even detect 1 positive T-cell among 100,000 cells.

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Latest Articles

Welcome to the Cytoart blog, where curiosity meets discovery and knowledge reigns.

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