Ovarian Cancer Monoclonal Antibody for CLIA & ELISA Immunoassay Development
CA125 (Cancer Antigen 125), encoded by the MUC16 gene, is a high-molecular-weight transmembrane mucin glycoprotein shed from the surface of epithelial cells of the peritoneum, fallopian tube, endometrium, and endocervix. Elevated serum CA125 (>35 U/mL) is the principal biomarker for epithelial ovarian cancer — the most lethal gynaecological malignancy — and is elevated in approximately 80% of advanced-stage cases.
For IVD sandwich immunoassay development, CA125 quantification requires antibodies targeting non-overlapping epitopes on different MUC16 domains. Sekbio supplies three CA125 antibodies spanning the two primary immunoreactive domains: S01-A107-1M and S01-A107-1H target the B-domain (similar to the OV185 reference clone), while S01-A107-2M targets the C-domain (similar to OV197). The recommended sandwich pair — B-domain capture + C-domain detection — mirrors the configuration of established CA125 II assays (Roche Elecsys, Abbott Architect) for clinical correlation.
CA125 testing is indicated for ovarian cancer diagnosis (in conjunction with ultrasound), treatment response monitoring after surgery or chemotherapy, and recurrence detection during post-treatment surveillance. The normal reference range is <35 U/mL (postmenopausal) and <200 U/mL (premenopausal).
Three CA125 antibodies targeting B-domain and C-domain epitopes for complete sandwich immunoassay system construction.
| Catalog No. | Product Name | Species / Format | Epitope Domain | Reference Clone | Purity | Storage |
|---|---|---|---|---|---|---|
| S01-A107-1M | Mouse Anti-CA125 mAb | Mouse mAb | B-domain | Similar to OV185 | >90% SEC-HPLC | +2°C to +8°C |
| S01-A107-1H | Humanized Anti-CA125 mAb | Humanized mAb | B-domain | Similar to OV185 | >90% SEC-HPLC | +2°C to +8°C |
| S01-A107-2M | Mouse Anti-CA125 mAb | Mouse mAb | C-domain | Similar to OV197 | >90% SEC-HPLC | +2°C to +8°C |
Recommended pairs: S01-A107-1M (capture, B-domain) + S01-A107-2M (detection, C-domain) for standard CLIA/ELISA; S01-A107-1H (capture, humanized) + S01-A107-2M (detection) for HAMA-sensitive applications. MOQ 1 mg. Contact info@sekbio.com for technical guidance.
Engineered for the sensitivity and specificity required in clinical ovarian cancer screening and monitoring assays.
S01-A107-1M (B-domain capture) and S01-A107-2M (C-domain detection) target structurally separate, non-overlapping domains of MUC16 — the prerequisite for effective sandwich immunoassay formation. This dual-domain configuration mirrors the CA125 II generation assay architecture used in Roche Elecsys and Abbott Architect platforms.
S01-A107-1H provides the identical B-domain binding specificity as S01-A107-1M but with humanized IgG framework residues, significantly reducing interference from human anti-mouse antibodies (HAMA). Recommended for CE-marked CLIA platforms intended for use in populations with elevated HAMA prevalence from biologic therapies.
The S01-A107-1M + S01-A107-2M pair achieves the 0.6–5,000 U/mL dynamic range required for CA125 clinical immunoassays, covering the normal reference range (<35 U/mL), borderline zone (35–200 U/mL), and high-concentration malignant disease values (>1,000 U/mL) without high-dose hook effect.
All CA125 antibodies are affinity-purified with purity >90% by SEC-HPLC and aggregation <5%. High purity reduces non-specific serum matrix binding that contributes to background signal — critical for the low-concentration performance (<10 U/mL) needed to accurately distinguish normal from borderline CA125 elevations.
CA125 immunoassay performance is highly sensitive to antibody lot variation — even small affinity shifts can shift the 35 U/mL diagnostic cut-off. Sekbio's ISO 13485-certified manufacturing ensures inter-batch CV <10%, protecting your assay's clinical performance from reagent lot changes during production supply.
ISO 13485-compliant manufacturing in Shenzhen, China with full Certificate of Analysis documentation. MOQ 1 mg for R&D; gram-scale OEM supply for production. Clinical correlation data vs Roche Elecsys CA125 II available upon request to support CE IVDR, NMPA, and FDA 510(k) submissions.
CA125 antibody pair validated for ovarian cancer diagnostics, treatment monitoring, and OEM kit development.
CA125 is the primary serum biomarker for epithelial ovarian cancer. Combined with transvaginal ultrasound, CA125 >35 U/mL (postmenopausal) drives the Risk of Malignancy Index (RMI) calculation used to triage pelvic masses for surgical referral. CLIA assays using Sekbio's CA125 antibody pair support CA125 II-equivalent performance for routine gynaecological oncology workflows in hospitals and clinics globally.
Serial CA125 measurements during platinum-based chemotherapy monitor tumour response per ESMO/NCCN CA125 response criteria. A >50% CA125 reduction from pre-treatment baseline correlates with pathological response. Quantitative CLIA or ELISA using Sekbio's antibody pair provides the inter-assay precision needed for longitudinal CA125 trend analysis across treatment cycles.
CA125 doubling to >2× nadir value, or any confirmed CA125 >35 U/mL (in patients who normalised), is the Gynaecologic Cancer InterGroup (GCIG) criteria for CA125 progression. ELISA kits using Sekbio's antibody pair enable regular (every 2–3 months) CA125 surveillance during the high-risk first 5 years post-treatment, supporting early reinstatement of systemic therapy.
IVD manufacturers developing CE-marked or NMPA-registered CA125 assays can integrate Sekbio's antibody pair with ISO 13485-compliant documentation and clinical correlation data. The availability of both mouse (S01-A107-1M) and humanized (S01-A107-1H) capture antibodies provides flexibility for HAMA interference management in global regulatory submissions.
Technical and commercial questions from IVD R&D engineers and procurement teams.
CA125 (MUC16) is a high-molecular-weight mucin glycoprotein elevated in epithelial ovarian cancer. CA125 >35 U/mL is the primary biomarker for ovarian cancer diagnosis, treatment monitoring, and recurrence surveillance per ESMO, NCCN, and SGO guidelines. CA125 is elevated in approximately 80% of advanced-stage ovarian carcinoma cases.
Sekbio supplies: S01-A107-1M (Mouse mAb, B-domain, similar to OV185), S01-A107-1H (Humanized mAb, B-domain, same epitope as 1M), and S01-A107-2M (Mouse mAb, C-domain, similar to OV197). Recommended sandwich pair: 1M or 1H (B-domain capture) + 2M (C-domain detection).
CA125/MUC16 carries two major antibody-binding domains: the B-domain (recognised by OV185-related clones, including S01-A107-1M/1H) and the C-domain (recognised by OV197-related clones, including S01-A107-2M). For sandwich immunoassay, non-overlapping epitopes from both domains are required — B-domain capture + C-domain detection — to enable simultaneous, unhindered antibody binding to the same CA125 molecule.
Use S01-A107-1H when developing CLIA assays for populations with elevated HAMA prevalence (patients on biologics, autoimmune disease patients). HAMA can cause false-positive CA125 results in mouse antibody-based assays. The humanized S01-A107-1H eliminates murine framework HAMA binding while retaining equivalent B-domain specificity.
Diagnostic cut-off: 35 U/mL (postmenopausal); 200 U/mL (premenopausal). Assay range for clinical use: 0.6–5,000 U/mL. The Sekbio CA125 antibody pair is validated to achieve this analytical range with <10% CV at the 35 U/mL cut-off, ensuring reliable discrimination at the clinically critical threshold.
Yes. S01-A107-1M + S01-A107-2M are validated for both CLIA and ELISA sandwich formats. Sekbio can supply pre-coated antibodies for microplate ELISA, biotinylated detection antibodies for streptavidin-HRP detection systems, and conjugated antibodies for direct enzyme-label formats. Contact info@sekbio.com for custom ELISA format preparation or visit our Oncology Markers page.
Request the full technical datasheet, antibody pair specifications, or discuss OEM supply with our team.