Gastric Cancer Monoclonal Antibody for CLIA & ELISA Immunoassay Development
CA72-4 (Cancer Antigen 72-4), also known as TAG-72 (Tumour-Associated Glycoprotein-72), is a high-molecular-weight mucin-like glycoprotein — a complex of mucins bearing the sialylated Tn antigen — expressed selectively on gastrointestinal, ovarian, and lung adenocarcinoma cells. CA72-4 is the most sensitive single serum biomarker for gastric (stomach) adenocarcinoma, with sensitivity of 40–50% at the 6 U/mL cut-off for stage II–IV disease, outperforming CEA and CA19-9 for gastric cancer when used alone.
For IVD sandwich immunoassay development, CA72-4 quantification requires antibodies targeting the two well-characterised TAG-72 epitopes: the CC49 epitope (sialylated Tn antigen cluster) and the B72.3 epitope (a distinct, non-overlapping TAG-72 protein/carbohydrate epitope). Sekbio supplies all four CA72-4 antibodies in the S01-A112 series: S01-A112-1M (mouse CC49), S01-A112-1H (humanized CC49), S01-A112-2M (mouse B72.3), and S01-A112-2H (humanized B72.3). The Roche-equivalent pair — S01-A112-1M (coated) + S01-A112-2H (conjugated, humanized) — is validated for CLIA and ELISA assay development.
CA72-4 is also elevated in colorectal and ovarian cancers and is used as part of multi-marker GI cancer panels alongside CEA and CA19-9. Normal reference: <6 U/mL.
Four CA72-4 antibodies covering CC49 and B72.3 TAG-72 epitopes, with mouse and humanized formats for HAMA-mitigated CLIA development.
| Catalog No. | Product Name | Species / Format | Epitope | Recommended Role | Purity | Storage |
|---|---|---|---|---|---|---|
| S01-A112-1M | Mouse Anti-CA72-4 mAb | Mouse mAb | TAG-72 / CC49 | Capture (Roche pair) | >90% SEC-HPLC | +2°C to +8°C |
| S01-A112-1H | Humanized Anti-CA72-4 mAb | Humanized mAb | CC49 | Capture (HAMA-mitigated) | >90% SEC-HPLC | +2°C to +8°C |
| S01-A112-2M | Mouse Anti-CA72-4 mAb | Mouse mAb | B72.3 | Detection alternative | >90% SEC-HPLC | +2°C to +8°C |
| S01-A112-2H | Humanized Anti-CA72-4 mAb | Humanized mAb | B72.3 | Detection (Roche pair) | >90% SEC-HPLC | +2°C to +8°C |
Roche-equivalent pair: S01-A112-1M (coated/capture, CC49) + S01-A112-2H (conjugated/detection, B72.3, humanized). MOQ 1 mg. OEM quantities from 10 mg to gram scale available. Contact info@sekbio.com for technical guidance.
Complete CC49 + B72.3 TAG-72 antibody panel with Roche-equivalent configuration and humanized variants, from a single ISO 13485 supplier.
S01-A112-1M (CC49 capture) + S01-A112-2H (B72.3 detection, humanized) mirrors the CC49 + B72.3 sandwich configuration of the Roche Elecsys CA72-4 assay. Clinical correlation data against Roche Elecsys CA72-4 supports CE IVDR and NMPA regulatory submissions for OEM manufacturers targeting Roche-traceable CA72-4 quantification.
S01-A112-2H (humanized B72.3) as the detection antibody in the Roche-equivalent pair substantially reduces false-positive CA72-4 results from HAMA interference in CLIA assays. The humanized framework retains identical B72.3 binding specificity with improved serum matrix performance in HAMA-positive patient samples from biologic or immunotherapy treatment.
The CC49 epitope (sialylated Tn antigen cluster) and B72.3 epitope (distinct TAG-72 carbohydrate/protein complex) are structurally non-overlapping — the essential requirement for sandwich immunoassay construction. Using S01-A112-1M (CC49) + S01-A112-2H (B72.3) ensures simultaneous, unhindered binding to the same TAG-72 molecule in patient serum.
The S01-A112-1M + S01-A112-2H pair is validated across the 0.5–300 U/mL analytical range required for clinical CA72-4 assays, covering the normal reference (<6 U/mL), borderline zone (6–20 U/mL), and high-concentration malignant values (>20–300 U/mL) with <10% CV at the 6 U/mL clinical decision cut-off.
All four CA72-4 antibodies are affinity-purified with purity >90% by SEC-HPLC. CA72-4/TAG-72 is a high-molecular-weight mucin complex — antibody purity directly impacts non-specific serum matrix binding. High-purity preparations minimise assay background, critical for detecting the low CA72-4 concentrations present in early-stage gastric cancer.
All S01-A112 series antibodies manufactured under ISO 13485 QMS with inter-batch CV <10% and full Certificate of Analysis documentation. Gram-scale OEM supply available. Custom formats — biotinylated, enzyme-conjugated, or colloidal gold-labelled — available upon request for direct kit integration without additional conjugation steps.
CA72-4 is the most sensitive single serum marker for gastric adenocarcinoma, outperforming CEA and CA19-9 alone. CA72-4 >6 U/mL supports staging in patients with resectable gastric cancer, and serial CA72-4 monitoring during adjuvant or palliative chemotherapy (FOLFOX, FLOT, HER2-targeted regimens) tracks treatment response and early recurrence detection.
The combination of CEA + CA19-9 + CA72-4 improves sensitivity for gastric cancer to 60–70% versus any single marker alone. Sekbio supplies matched antibody pairs for all three biomarkers — CEA, CA19-9 (S01-A111 series), and CA72-4 (S01-A112 series) — enabling integrated GI cancer panel CLIA or ELISA kit development from a single ISO 13485-certified raw material supplier.
CA72-4 complements CA125 in ovarian cancer management — elevated CA72-4 in CA125-seronegative patients expands biomarker coverage for mucinous ovarian carcinoma, which typically shows low CA125 expression. The CA125 + CA72-4 combined panel improves sensitivity for the mucinous subtype from ~40% (CA125 alone) to ~65%, supporting comprehensive ovarian cancer monitoring panel development.
IVD manufacturers developing CE-marked or NMPA-registered CA72-4 assays can use the Roche-equivalent S01-A112-1M + S01-A112-2H pair with ISO 13485-compliant batch documentation and clinical correlation data. All four S01-A112 series antibodies are available for systematic pair optimisation. Humanized S01-A112-1H and S01-A112-2H provide HAMA mitigation flexibility across assay configurations.
CA72-4 (TAG-72) is a mucin-like glycoprotein expressed on gastric, colorectal, and ovarian adenocarcinoma cells. It is the most sensitive single serum biomarker for gastric adenocarcinoma (sensitivity 40–50% at 6 U/mL cut-off), outperforming CEA and CA19-9 for gastric cancer. CA72-4 is used for staging, treatment monitoring, and recurrence detection in gastric and ovarian cancers.
4 antibodies: S01-A112-1M (mouse, CC49 epitope), S01-A112-1H (humanized, CC49), S01-A112-2M (mouse, B72.3 epitope), S01-A112-2H (humanized, B72.3). Recommended Roche-equivalent pair: S01-A112-1M (capture, CC49) + S01-A112-2H (detection, B72.3, humanized).
Roche-equivalent pair: S01-A112-1M (coated/capture, CC49 mouse) + S01-A112-2H (conjugated/detection, B72.3 humanized). This mirrors the CC49 + B72.3 configuration of the Roche Elecsys CA72-4 assay. Using the humanized S01-A112-2H as the detection antibody reduces HAMA interference versus a fully mouse pair. Clinical correlation data available upon request.
CC49 targets the sialylated Tn antigen cluster on TAG-72 (carbohydrate-type epitope); B72.3 targets a distinct non-overlapping epitope on the TAG-72 protein/carbohydrate backbone. Their structural non-overlap is the prerequisite for sandwich immunoassay construction — CC49 capture + B72.3 detection allows simultaneous binding to the same TAG-72 antigen.
HAMA (human anti-mouse antibodies) can cause false-positive CA72-4 results in CLIA assays using mouse detection antibodies. S01-A112-2H (humanized B72.3) replaces mouse framework residues with human IgG sequences, eliminating HAMA binding to the detection antibody while retaining identical B72.3 epitope specificity — the configuration used in the Roche-equivalent pair.
MOQ is 1 mg for R&D evaluation. All four S01-A112 antibodies available from 10 mg to gram scale for OEM production. Storage: all mAbs and humanized variants stable at +2°C to +8°C short-term; −20°C long-term. Shelf life 3 years. Contact info@sekbio.com for pair guidance or visit our Oncology Markers page.
Request the full technical datasheet, pair selection guidance, or discuss OEM supply with our team.