PD-1 CHO Cell Line

What it means: The parental cell line is the host in which the transgene or reporter was stably integrated. CHO-K1 (Chinese Hamster Ovary K1 subclone) is a epithelial-like, adherent cell line selected for this product.

Why it matters:

• Enables proline-auxotrophic subclone; routinely used for stable transfection and G-protein-coupled receptor (GPCR) functional assays.
• The parental background determines endogenous receptor expression, growth properties, and media requirements—verify compatibility with your assay conditions.
• Secondary reagents (antibodies, growth media) should be validated for this host species and cell type.

How to interpret here: This product is engineered on a CHO-K1 background. Pathway activity readouts, IC50/EC50 values, and control responses are calibrated for this host. Results may differ in alternative cell backgrounds.

What it means: Species refers to the biological origin of the expressed gene or protein target in this cell line. This product is classified as Chinese Hamster origin.

Why it matters:

• CHO-derived lines express the transgene in a non-human mammalian background with low endogenous human receptor cross-talk—advantageous for pharmacological functional assays requiring minimal background.
• Species origin directly affects antibody cross-reactivity, functional assay interpretation, and translational relevance of results.
• Confirm that your detection antibodies, assay controls, and signaling reagents are validated for Chinese Hamster targets.

How to interpret here: The Chinese Hamster designation indicates the sequence and biological context of the expressed construct—not necessarily the host cell species. Check the host cell line chip for the cellular background.

What it means: BSL-1 (Biosafety Level 1) indicates this agent is not known to cause disease in healthy adults and poses minimal risk to laboratory personnel and the environment.

Why it matters:

• Standard microbiological practices apply; no special containment facility is required beyond a clean bench.
• Routine PPE (gloves, lab coat, eye protection) and hand-washing protocols are sufficient.
• Institutional Biosafety Committee (IBC) registration may still be required for genetically modified organisms—consult your IBC before use.

How to interpret here: BSL-1 means this cell line can be handled on an open bench in a standard laboratory. Check your institution's IBC policy, particularly if the construct contains a selectable antibiotic resistance marker or modified genetic elements.

What it means: Recombinant Cell Line. A Recombinant Cell Line stably expresses a heterologous gene of interest in the host cell background at defined levels confirmed by molecular characterization.

Why it matters:

• Stable integration ensures reproducible target expression across passages, eliminating the variability of transient transfection experiments.
• Select the correct product type based on whether your experiment requires overexpression, loss-of-function, pathway reporting, or immune effector function.

How to interpret here: This Recombinant Cell Line expresses the target protein indicated in the product title. Verify protein expression by Western blot or functional assay upon receipt and after extended culture.

What it means: Confirmed Negative indicates this cell line was screened using a validated mycoplasma detection assay prior to release and confirmed negative for mycoplasma contamination.

Why it matters:

• Mycoplasma contamination can significantly alter gene expression profiles, proliferation rates, metabolism, and assay readouts—potentially invalidating experimental results without visible signs of contamination.
• Testing prior to use is considered best practice in accordance with ATCC and ECACC guidelines for cell line authentication.
• BPS Bioscience uses validated PCR-based or luminescence-based detection kits (e.g., Venor™GeM, MycoAlert™) for screening.

How to interpret here: Confirmed Negative confirms the product shipped to you passed mycoplasma screening at the time of manufacture. We still recommend performing routine mycoplasma testing in your laboratory after receipt and during extended culture to confirm ongoing negative status.

Tip: Test your cell cultures for mycoplasma at regular intervals (e.g., every 2–4 weeks) regardless of the vendor QC status. Contamination can be introduced during routine culture handling.

What it means: Liquid Nitrogen storage indicates this cell line must be maintained in vapor-phase or liquid-phase liquid nitrogen (≤-130°C) for long-term preservation of viability and function.

Why it matters:

• Liquid nitrogen cryopreservation halts cellular metabolism and ice crystal formation, preserving cell viability and transgene expression stability for extended periods.
• Storage above -130°C (e.g., -80°C freezer) is not equivalent—cells may lose viability within weeks to months at -80°C.
• Transfer cells from dry-ice shipping to Liquid Nitrogen storage immediately upon receipt to prevent viability loss.

How to interpret here: Liquid Nitrogen storage is required for this product. Access to a liquid nitrogen Dewar or cryogenic storage tank is essential before ordering. Do not store in a standard -80°C freezer as long-term cryostorage.