The recombinant human FOLR1 protein production includes gene cloning, plasmid engineering, protein expression, purification, and testing. Primers are designed to amplify the gene segment encoding the 25-233aa of human FOLR1, which is cloned into a plasmid with a C-terminal 10xHis-tag. Mammalian cells are transfected with this plasmid, followed by selective antibiotic screening for the positive cells. The positive cells are cultured for protein expression. The FOLR1 protein is released via cell lysis and purified through Ni-NTA affinity chromatography. Protein purity, assessed by SDS-PAGE and SEC-HPLC, exceeds 95%, and protein endotoxin levels, measured by the LAL method, are below 1.0 EU/μg. ELISA demonstrates the recombinant FOLR1 protein's functional binding to the FOLR1 recombinant antibody (CSB-RA008784MA1HU), with an EC50 ranging from 6.893 to 7.883 ng/mL.
Human folate receptor alpha (FRα), also known as FOLR1, is a GPI-anchored membrane protein predominantly expressed in certain epithelial tissues and is notably overexpressed in various malignancies, including ovarian, lung, breast, and renal cancers while exhibiting limited expression in normal tissues [5][6][12].
FOLR1 mainly facilitates the transport of folate into cells through receptor-mediated endocytosis, a process that significantly enhances the efficiency of folate uptake compared to other transport mechanisms [4][14]. The endocytic pathway allows FOLR1 to internalize folate, which is then released into the cytoplasm for utilization in critical metabolic pathways, including DNA synthesis and repair, and amino acid metabolism [1][3][8][9][15].
FOLR1 is critical for fetal development, as it mediates the transport of folate from the mother to the fetus, thereby influencing neurodevelopmental outcomes [7][10]. Disruptions in FOLR1 function, such as the presence of autoantibodies against the receptor, have been associated with conditions like autism spectrum disorder and cerebral folate deficiency, highlighting the receptor's significance in both developmental and pathological contexts [11][15].
In the context of cancer, the overexpression of FOLR1 has been leveraged for targeted therapies, particularly in drug delivery systems that utilize folate-conjugated agents to selectively deliver cytotoxic drugs to cancer cells [5][16]. This targeting strategy exploits the high expression levels of FOLR1 in tumor tissues, allowing for enhanced therapeutic efficacy while minimizing systemic toxicity [6][14]. Recent studies suggest that FOLR1 may also participate in signaling pathways that influence tumor growth and metastasis [2][13].
References:
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