CAR γδ T Cell Viability Test

Nowadays, CAR TCR-engineered γδ T cell development is starting to show up in cellular immunotherapy strategy. As a leading company in the cell therapy field, Creative Biolabs has established a comprehensive platform to provide global customers with entire CAR TCR-engineered γδ T cells development services, including CAR γδ T cell viability test to ensure the quality of the engineered cells.

Importance of CAR TCR-Engineered γδ T Cells

Harnessing the immune system to recognize and destroy tumor cells is quickly becoming a cornerstone of cancer treatment. One of the principal treatment modalities within the field of cancer immunotherapy is adoptive T cell therapy (ACT). CAR is a fusion protein in which a tumor-associated antigens (TAA)-binding moiety (usually a single-chain variable fragment scFv derived from a monoclonal antibody) is linked to an intracellular immunoreceptor signaling domain, typically the CD3 ζ chain. CAR T cells can potentially redirect the effector functions of a T cell towards any protein or non-protein target expressed on the cell surface. Therefore, CAR T cells can recognize various protein and non-protein antigens without the requirement of antigen processing and presentation by the target cell. Bypassing the requirement for major histocompatibility complex (MHC)-restricted targets also means that the CAR T-cell approach can be used as a universal treatment, broadening the potential of applicability of adoptive T-cell therapy.

Fig.1 “Co-stimulation Only” CAR-γδ T cell activation after recognition of two separate tumor-associated molecules. (Parihar, 2017)

Services of γδ T Cell Viability Test at Creative Biolabs

Creative Biolabs provides entire CAR engineered γδ T cell development services including the establishment of CAR engineered γδ T cells and subsequent viability test. Our optimized platform will offer worry-free viability services. Here we list two of the most common CAR γδ T cell viability test methods as follow:

• Cell Counting Kit 8 (CCK 8) assay

Cell Counting Kit-8 is a colorimetric assay for the determination of viable cell numbers and can be used for cell proliferation assays as well as cytotoxicity tests. Cell Counting-8 uses a tetrazolium salt, WST-8, which produces the water-soluble WST-8 formazan. Since this orange colored formazan does not require dissolving, no solubilizing process is required. WST-8 is not cell-permeable, which results in low cytotoxicity. Therefore, after assaying the cells with Cell Counting kit-8 it is possible to continue using those cells for further experiments.

• Annexin V and 7-AAD staining kit

  Apoptosis, or programmed cell death, is an important and active regulatory pathway of cell growth and proliferation. Cells respond to specific induction signals by initiating intracellular processes that result in characteristic physiological changes. Among these are the externalization of phosphatidylserine (PS) to the cell surface, cleavage and degradation of specific cellular proteins, compaction and fragmentation of nuclear chromatin, and loss of membrane integrity (in late stages). Annexin V is a calcium-dependent phospholipid-binding protein with a high affinity for PS, a membrane component normally localized to the internal face of the cell membrane. Early in the apoptotic pathway, molecules of PS are translocated to the outer surface of the cell membrane where Annexin V can readily bind them. 7-AAD is a membrane impermeant dye that is generally excluded from viable cells. It binds to double-stranded DNA by intercalating between base pairs in G-C-rich regions. Four populations of cells can be distinguished in this assay:

  • Non-apoptotic cells: Annexin V (-) and 7-AAD (-)
  • Early apoptotic cells: Annexin V (+) and 7-AAD (-)
  • Late stage apoptotic and dead cells: Annexin V (+) and 7-AAD (+)
  • Mostly nuclear debris: Annexin V (-) and 7-AAD (+)

With an experienced expert team, Creative Biolabs offers high-quality CAR γδ T cell viability test services. We will do our best to satisfy customers' detailed requirements. If you have any puzzles about our services, please feel free to contact us for more information.

Reference

1. Parihar, R. Sensing bad: Are co-stimulatory car-expressing gammadelta t cells safer? Mol Ther. 2017, 25(5): 1064-1066.