• EGFR is expressed in various tissues. Upon binding of ligands like EGF to the EGFR receptor, EGFR dimers are formed. The activation of EGFR dimers stimulates intracellular tyrosine kinases, resulting in phosphorylation that triggers downstream signaling cascades, leading to cancer cell proliferation and the proliferation of new blood vessels within cancer cells. The mechanism of action of EGFR-targeting drugs primarily involves blocking or inhibiting the activity of EGFR, thereby preventing the growth and spread of cancer cells.
• A chimeric CDS that encode human EGFR extracellular domain, mouse EGFR signal peptide, transmembrane and cytoplasmic domain, followed by mouse 3’UTR-STOP was inserted right after mouse Egfr exon2.
• Human EGFR mRNA and protein were detected in B-hEGFR mice(C).
• This product is used for tumor pharmacology and safety evaluation of anti-human EGFR antibodies.

Gene targeting strategy for B-hEGFR mice(C). A chimeric CDS that encode human EGFR extracellular domain, mouse EGFR signal peptide, transmembrane and cytoplasmic domain, followed by mouse 3’UTR-STOP was inserted right after mouse Egfr exon2. The chimeric EGFR protein expression was driven by endogenous mouse Egfr promoter, while mouse Egfr gene transcription and translation will be disrupted.

Strain specific analysis of EGFR mRNA expression in wild-type BALB/cCrSlcNifdc and B-hEGFR mice(C) by RT-PCR. Liver RNA were isolated from wild-type BALB/cCrSlcNifdc (+/+) and homozygous B-hEGFR mice(C) (H/H), then cDNA libraries were synthesized by reverse transcription, followed by PCR with mouse or human EGFR primers. mouse Egfr mRNA was only detectable in wild-type BALB/cCrSlcNifdc. Human EGFR mRNA was exclusively detectable in homozygous B-hEGFR mice(C) but not in wild-type BALB/cCrSlcNifdc.

Immunohistochemical (IHC) analysis of EGFR expression in B-hEGFR mice(C). The ten tissues were collected from wild-type BALB/cCrSlcNifdc mice and B-hEGFR mice(C) (female, 6-week-old), analyzed by IHC with anti-EGFR (Invitrogen, MA5-49312). Human EGFR was detectable in brain, ovary, lung, liver, kidney, skin, uterus, and esophagus of B-hEGFR mice(C) but not in spleen and thyroid. Meantime, human EGFR was not detectable in tissues of BALB/cCrSlcNifdc mice. The arrow indicates tissue cells with positive EGFR staining (brown). “+” indicates that the tissue is positive, and “-” indicates that the tissue is negative.