The ITFG1 Knockout NCI-H1975 Polyclonal Cells are a CRISPR/Cas9-mediated gene-disrupted polyclonal cell population derived from the NCI-H1975 human lung adenocarcinoma epithelial cell line. This polyclonal knockout product offers a genetically heterogeneous pool of cells harboring targeted disruption of the ITFG1 gene, enabling loss-of-function studies without selecting a single clonal isolate. The polyclonal format maintains population-level diversity while abolishing functional ITFG1 protein expression, providing a robust model to interrogate tumor-intrinsic and immune-modulatory roles of ITFG1 in a physiologically relevant cancer context.
The host NCI-H1975 cell line is a well-characterized model of non-small cell lung cancer (NSCLC) originating from a female patient with lung adenocarcinoma. It carries activating EGFR mutations L858R and T790M, which confer sensitivity to first- and third-generation EGFR tyrosine kinase inhibitors, alongside a TP53 R273H missense mutation. This genetic landscape renders NCI-H1975 cells indispensable for studying EGFR-driven oncogenesis, acquired resistance mechanisms to agents such as osimertinib, and the interplay between mutational status and the tumor microenvironment. The cell line??s epithelial derivation and tumorigenic properties further support investigations into invasion, migration, and metastatic potential.
ITFG1 encodes the T-cell immunomodulatory protein TIP, a ligand that directly engages the costimulatory receptor CD28 and the inhibitory checkpoint receptor CTLA-4 on T cells. Upstream of ITFG1, T cell receptor (TCR) stimulation and CD28 costimulation activate NFAT transcription factors, which promote ITFG1 expression. Subsequently, ITFG1-mediated signaling propagates downstream to activate NF-??B and MAPK/ERK pathways, leading to transcriptional induction of IL-2 and AP-1-dependent cytokine production. This cascade drives T cell proliferation and effector functions. ITFG1 also interacts with B7 family members and participates in cell adhesion signaling, contributing to immune synapse stabilization and bidirectional communication between tumor cells and T cells.
Disruption of ITFG1 in NCI-H1975 lung adenocarcinoma cells creates a powerful platform for dissecting tumor-immune crosstalk within the NSCLC microenvironment. Loss of TIP expression on tumor cells eliminates their ability to provide costimulatory or checkpoint signals to infiltrating T lymphocytes via CD28 or CTLA-4 engagement, thereby altering NF-??B and MAPK/ERK signaling outputs and downstream IL-2 secretion. This perturbation facilitates examination of how tumor-derived immunomodulatory cues influence T cell activation, exhaustion, and anti-tumor immunity. Additionally, the well-defined EGFR mutation background permits investigation of potential crosstalk between ITFG1 signaling and EGFR inhibitor response, shedding light on mechanisms linking oncogenic and immune regulatory pathways in lung adenocarcinoma.
This polyclonal knockout cell population is ideally suited for tumor-immune interaction studies, functional analysis of ITFG1 in lung adenocarcinoma, and immune checkpoint regulatory screens. Researchers can validate ITFG1 disruption via Western blotting, RT-qPCR, and flow cytometry for surface TIP. T cell co-culture experiments combined with IL-2 ELISA and proliferation assays enable quantification of T cell activation modulation. EGFR inhibitor sensitivity profiling with osimertinib reveals whether ITFG1 loss impacts drug response, while migration and invasion assays assess phenotypic changes in tumor behavior. For further information and technical support, please contact Ascent Research.
