Product Overview Data Sheet Protocol
In the context of rabbit antibody engineering, there are multiple types of kappa light chain constant regions. While the rabbit has two main kappa isotypes (K1 and K2), K1 is the dominant form, representing about 90% of the repertoire. Within K1, several genetic variants (allotypes) exist, with b4 and b9 being the most frequently discussed in the literature.
| Feature | K1-b4 Allotype | K1-b9 Allotype |
|---|---|---|
| Prevalence | Most common in standard lab rabbits. | Found in specific pedigreed strains. |
| Disulfide Bond | Interdomain bond between Cys80 (VL) and Cys171 (CL). | Interdomain bond between Cys108 (VL) and Cys171 (CL). |
| Engineering Utility | High in native rabbit systems. | Superior for chimeric/recombinant work. |
| Expression Level | Can be poor in chimeric formats (e.g., mouse-rabbit). | Consistently higher in chimeric and recombinant formats. |
This vector is a constitutive mammalian expression vector designed to deliver exceptionally high levels of antibody expression. This circular vector features an enhanced, full-length CMV promoter and other expression elements that typically enable higher expression levels. It can be used in suspension-adapted cells, such as Expi293F™ and ExpiCHO™, for transient protein expression. Additionally, it can serve as a Geneticin®-selectable expression plasmid for engineering stable cell lines. The vector carries an ampicillin resistance gene.
Specifications of Antibody Expression Vector| Antibiotic Resistance | Ampicillin (AmpR) |
| Constitutive or Inducible System | Constitutive |
| Delivery Type | Transfection |
| Promoter | CMV |
| Product Type | Mammalian Expression Vector |
| Cloning Method | Restriction Enzyme (5’-AgeI; 3’-XhoI) or Homologous Assembly |
Contents & Storage
- 5.0 µg of pFB-CLIg-rk1-b9 in Tris-EDTA buffer
- Store at -20°. Vectors are guaranteed stable for 12 months when properly stored.
Materials required for antibody generation and isotype switching
pFB-CHIg-rG plasmid expressing the rabbit heavy chain.
Vector usage
- Entire monoclonal IgG antibodies production: cloning your heavy/light chain variable regions in the cloning sites to preserve the integrity of the heavy/light chain constant region;
- Isotype switching: pFB-CHIg-rG with pFB-CLIg-rk1-b4, pFB-CLIg-rk1-b9, or pFB-CLIg-rl plasmids are designed to switch a monoclonal antibody from one isotype to another, therefore maintaining the generated new antibodies with the same antigen affinity (epitopes) but with different effector functions (enhanced or reduced or even disabled ADCC and CDC).
