CT26.WT Syngeneic Model Service for Colon Cancer

The CT26.WT syngeneic model is the workhorse immunocompetent platform for colorectal cancer research, engrafting the clonally purified wild-type derivative of the classic NNMU-induced CT26 carcinoma into syngeneic BALB/c hosts with extraordinary efficiency. Alfa Cytology delivers this benchmark model as a complete preclinical service — authenticated cell banking, subcutaneous flank or orthotopic cecal implantation, experimental and spontaneous metastasis formats, checkpoint-inhibitor and combination testing, and full histopathology — giving sponsors a fast, reproducible, immune-intact colon cancer system without building syngeneic model infrastructure in-house.

Overview of CT26.WT Syngeneic Model for Colon Cancer

CT26 was born in the 1970s from classical chemical carcinogenesis — a BALB/c mouse colon carcinoma induced by N-nitroso-N-methylurethane (NNMU), a potent nitrosamine carcinogen — and was subsequently cloned to generate CT26.WT (ATCC CRL-2638), the purified line carrying the undifferentiated, microsatellite-stable carcinoma phenotype that laboratories rely on today. The cells display fibroblast-like morphology with adherent growth, express the H-2^d haplotype, and are prodigiously tumorigenic: subcutaneously inoculated BALB/c mice develop lethal tumors at 80% frequency with as few as 10³ cells and 100% frequency at 10⁴ cells, while intravenous injection of 10⁴ cells reliably seeds pulmonary metastases. Genetically, CT26 carries an activating Kras mutation together with a β-catenin mutation but retains wild-type p53 — an unusual combination that differs instructively from typical human colorectal cancer and that shapes its distinctive drug-response profile.

Fig 1. Comparative workflow of the parental CT26.WT versus metastatic derivative CT26.MtC3 in the BALB/c syngeneic colorectal cancer model — in vivo metastatic dissemination, immune profiling and checkpoint therapy sensitivity mapping between the paired cell lines. (Bienassis, CéliaZ, et al., 2026)

What has made CT26.WT a fixture of preclinical oncology for five decades is not merely its vigor but its utility as an immunological instrument. As a syngeneic line, it preserves the complete host immune compartment, and it pairs naturally with its sister line CT26.CL25 (ATCC CRL-2639), which was stably transduced with a retroviral lacZ vector to express the model tumor-associated antigen beta-galactosidase while matching CT26.WT in growth rate and lethality — together they form the classic system for testing immunotherapy protocols and dissecting host antitumor responses, from fowlpox vaccine vectors to LIGHT/IL-2 combination immunotherapy. The model grows quickly, responds to liver, lung, and lymph node metastasis questions, and has contributed foundational checkpoint findings — notably, CT26 is among the lines in which antibody-based anti-PD-1 monotherapy shows limited benefit while alternative modalities such as GSK3-inhibitor nanocarriers achieve growth control. Luciferase-tagged CT26.WT-Luc reporter lines enable quantitative bioluminescence tracking of flank, orthotopic cecal, and metastatic disease on IVIS-class imagers. For preclinical teams, the platform offers a rare combination: near-certain tumor takes, brisk timelines, an extensively annotated immune profile, and a sister-line antigen system that few other syngeneic models can match.

Cell Line Information: CT26.WT

CT26.WT (ATCC CRL-2638; Cellosaurus CVCL_7256; Cytion 305178) is the clonally purified wild-type derivative of the NNMU-induced CT26 colon carcinoma line, deposited with the American Type Culture Collection. The luciferase-tagged CT26.WT-Luc variant (e.g., Ubigene YC-B003-Luc-P) is generated by stable reporter transduction and supports quantitative in vivo imaging. Core characteristics are compiled below.

Our Services

Engaging Alfa Cytology for the CT26.WT syngeneic model consolidates a complete, IACUC-compliant program under one accountable team: authenticated, low-passage CT26.WT or CT26.WT-Luc banks are maintained with the line's temperature-sensitive culture quirks respected, syngeneic BALB/c hosts are sourced and acclimated, tumors are established by subcutaneous, orthotopic cecal, or metastatic-seeding routes at the model's documented low-cell efficiencies, and treatment arms — from checkpoint inhibitors and vaccine formats to chemotherapy combinations — run through scheduled bioluminescence imaging and terminal histopathology, all returned as an audit-ready data package.

Workflow of CT26.WT Syngeneic Model Construction

CT26.WT studies offer an unusually wide design space — flank screening, orthotopic cecal modeling, and intravenous metastasis formats — all built on the same disciplined cell preparation. A standard program proceeds as follows.

1. Cell preparation and quality control: CT26.WT or CT26.WT-Luc cells are expanded at low passage, confirmed mycoplasma-free, and luciferase activity validated in vitro; given the line's temperature sensitivity, suspensions are kept warmed and handled promptly before inoculation.
2. Host selection and acclimation: Male or female BALB/c mice, typically 6–10 weeks of age, are quarantined and acclimated in a specific-pathogen-free barrier facility, with cohort sizing matched to the near-100% take rates.
3. Implantation: subcutaneous route. Cells (commonly 10⁵–10⁶ in 0.1 mL PBS, or as few as 10³–10⁴ where the model's extreme tumorigenicity is exploited) are injected into the flank; the site is compressed briefly on needle withdrawal, and tumors become palpable within days.
4. Implantation: orthotopic cecal route. Under isoflurane anesthesia, a midline laparotomy exposes the cecum, and a defined cell suspension is injected into the cecal wall with a fine needle; the cecum is returned to the abdomen and the incision closed, enabling primary colonic tumors with physiologic metastatic spread.
5. Implantation: metastatic-seeding route. For experimental metastasis studies, a bolus (classically ~10⁴ cells) is injected intravenously, reliably seeding pulmonary nodules within the model's published range.
6. Randomization and treatment: Mice are randomized into arms at a defined tumor volume or imaging threshold, and test articles, checkpoint inhibitors, vaccine formats, or combination regimens are dosed per protocol, with body weight and clinical signs recorded at defined intervals.
7. Longitudinal monitoring: Flank tumors are measured by caliper; luciferase-tagged cohorts undergo bioluminescence imaging after intraperitoneal D-luciferin injection to quantify primary growth and metastatic burden on the protocol cadence.
8. Endpoint analysis and reporting: At termination, tumors and metastatic organs are resected, weighed, and dimensioned; tissues undergo H&E and immunohistochemistry (including CD8, FoxP3, F4/80, PD-L1 panels), tumor-infiltrating leukocytes are profiled by flow cytometry where specified, and all data are consolidated into the final report.

Fig 2. CT26.WT Syngeneic Model construction workflow.

Case Study-CT26.WT Syngeneic Model Development

Alfa Cytology has applied the CT26.WT syngeneic platform to preclinical programs spanning checkpoint blockade evaluation, cytokine and vaccine combination strategies, chemotherapy regimens, and metastasis-focused study designs in colorectal cancer. In these engagements, caliper and bioluminescence readouts tracked primary and metastatic tumor kinetics, while terminal histopathology with immune-marker panels and flow-cytometric tumor-infiltrating-leukocyte profiling completed the pharmacological and immunological assessment. Study parameters — implantation route, inoculum size, monitoring cadence, and endpoint panels — are tailored to each program. Case materials can be shared under confidentiality agreements upon request.

Why Choose Alfa Cytology?

CT26.WT rewards teams that respect its quirks — the temperature-sensitive culture behavior, the extreme low-cell tumorigenicity that demands precise inocula, and the immunological sophistication the sister-line system implies. Alfa Cytology fields these capabilities in-house, making the CT26.WT / CT26.WT-Luc syngeneic model a dependable backbone for your colorectal cancer program.

• Documented ATCC provenance, with low-passage banking and authenticated CT26.WT-Luc reporter lines.
• Respect for the line's culture quirks, including temperature sensitivity and aggregation behavior, protecting study reproducibility.
• Three implantation formats — flank, orthotopic cecal, and intravenous metastatic seeding — under one roof.
• Sister-line pairing expertise with CT26.CL25 for antigen-defined immunotherapy designs.
• Extreme tumorigenicity exploited precisely, from 10³-cell studies to standard 10⁶-cell flank work.
• Full immune-profiling endpoints, including TIL flow cytometry and checkpoint immunohistochemistry.
• IACUC-compliant, documentation-rich operations delivering audit-ready records throughout the study.

Contact Us

If your colorectal cancer program needs a battle-tested immunocompetent platform, contact us today to discuss CT26.WT / CT26.WT-Luc study design, implantation format, and endpoint strategy with our scientific team. Reach out for a confidential consultation and project quotation — Alfa Cytology looks forward to advancing your next preclinical study.

For research use only. Not intended for any clinical use.