FOLR1 antibodies are primarily used to detect protein expression in research and clinical settings. These include polyclonal and monoclonal variants, often paired with HRP-conjugated secondary antibodies for signal amplification in assays like Western blotting (WB) and immunohistochemistry (IHC).
HRP is commonly employed in secondary antibodies to enhance signal detection. While primary FOLR1 antibodies are typically unconjugated, their compatibility with HRP-based systems is critical for assay sensitivity.
Western Blotting: Primary FOLR1 antibodies (e.g., AF5646, MAB5646) bind to target protein, followed by HRP-conjugated secondary antibodies (e.g., anti-goat or anti-mouse IgG) to catalyze chromogenic or chemiluminescent reactions .
Immunohistochemistry: HRP-conjugated detection systems (e.g., VENTANA FOLR1-2.1) enable visualization of FOLR1 in tumor tissues, aiding in prognostic assessments .
| Antibody | Sensitivity | Specificity | Cross-Reactivity |
|---|---|---|---|
| AF5646 | Detects FOLR1 in MCF7 and HeLa cells | No cross-reactivity with FOLR3 or mouse FOLR1 | <15% cross-reactivity with recombinant mouse FOLR1 |
| MAB5646 | Identifies FOLR1 in human cortex lysates | Specific to human FOLR1 | No reported cross-reactivity |
| 23355-1-AP | Detects FOLR1 in breast cancer tissues | Validated in WB and IHC | Reacts with human, mouse, and rat FOLR1 |
FOLR1 antibodies have advanced understanding of cancer biology and therapeutic targeting:
Breast Cancer: Triple-negative breast cancers (TNBC) exhibit higher FOLR1 mRNA and protein levels, correlating with poor prognosis .
Ovarian Cancer: FOLR1 overexpression is linked to tumor aggression and resistance to chemotherapy .
MORAb-202: An anti-FOLR1 antibody–drug conjugate (ADC) with eribulin as the payload, showing efficacy in FOLR1-positive breast and lung cancer models .
CAR T-Cell Therapy: Fully human FOLR1-targeting CAR constructs demonstrate cytotoxicity against ovarian cancer cells, with minimal off-target effects .
The VENTANA FOLR1 (FOLR1-2.1) RxDx Assay uses a mouse monoclonal antibody to detect FOLR1 in epithelial ovarian cancer (EOC) tissues, with high interprecision accuracy (12 FOLR1-positive vs. 12 FOLR1-negative specimens) .