Recombinant Antibody (scFv) Production Services

Our recombinant antibody (single-chain variable fragment, scFv-Fc) production services include: 1) Optimization and synthesis of antibody variable regions (VH and VL) or scFv-Fc antibodies for molecular construction of recombinant scFv-Fc antibodies with our proprietary antibody expression vectors; 2) transient production of recombinant antibodies in CHO cells; 3) purification of recombinant antibodies. Made as a single protein, scFv-Fc retains the specificity of the original immunoglobulin, and in certain applications is preferable to whole IgG in construction speed, production yield, and engineering flexibility.

Synthesizing antibody variable regions (both VH and VL) or sequences that clients provide:
Including sequence optimization, for free, to meet your goals such as recombinant antibody expression at high and reliable levels.

Construction, expression, and purification of scFv-Fc (choice of human or mouse IgG1-Fc backbone; other recombinant IgG-Fc construction is available upon request):
* Connect VH with VL using a short linker peptide of 10-25 amino acids;
* Construct the recombinant scFv-Fc;
* Transiently express the recombinant scFv-Fc protein in CHO cells;
* Purify the recombinant IgG antibody with Protein A and if needed, at least one additional purification method.

The Fc options include but are not limited to:
* Human IgG1-Fc, IgG2-Fc, IgG3-Fc, IgG4-Fc;
* Mouse IgG1-Fc, IgG2a-Fc, IgG2b-Fc, IgG3-Fc;
* Rat IgG1-Fc, IgG2a-Fc, IgG2b-Fc, IgG3-Fc;
* Rabbit IgG-Fc;
* Canine IgG-Fc.

Deliverable:
A. Purified scFv-Fc protein (from CHO transient production);
B. Study report.

BS079B:
Gene synthesis of the variable regions of the recombinant scFv-Fc antibody;
Molecular construction of the recombinant scFv-Fc antibody;
0.1 Liter transient production of the recombinant scFv-Fc antibody in CHO cells (7-day fed-batch cell culturing);
At least 2-step antibody protein purification;
Quality guarantee: SDS-PAGE >95%, SEC-HPLC >95%, and endotoxin <1 EU/mg. Mass spectrometry may be used to check molecular weight of the purified antibody.

BS079B-14:
Gene synthesis of the variable regions of the recombinant scFv-Fc antibody;
Molecular construction of the recombinant scFv-Fc antibody;
0.1 Liter transient production of the recombinant scFv-Fc antibody in CHO cells (14-day fed-batch cell culturing);
At least 2-step antibody protein purification;
Quality guarantee: SDS-PAGE >95%, SEC-HPLC >95%, and endotoxin <1 EU/mg. Mass spectrometry may be used to check molecular weight of the purified antibody.

BS079B-05:
Gene synthesis of the variable regions of the recombinant scFv-Fc antibody;
Molecular construction of the recombinant scFv-Fc antibody;
0.1 Liter transient production of the recombinant scFv-Fc antibody in CHO cells (7-day fed-batch cell culturing);
At least 2-step antibody protein purification;
Quality guarantee: SDS-PAGE >95%, SEC-HPLC >95%, and endotoxin <0.05 EU/mg. Mass spectrometry may be used to check molecular weight of the purified antibody.

BS079B-14-05:
Gene synthesis of the variable regions of the recombinant scFv-Fc antibody;
Molecular construction of the recombinant scFv-Fc antibody;
0.1 Liter transient production of the recombinant scFv-Fc antibody in CHO cells (14-day fed-batch cell culturing);
At least 2-step antibody protein purification;
Quality guarantee: SDS-PAGE >95%, SEC-HPLC >95%, and endotoxin <0.05 EU/mg. Mass spectrometry may be used to check molecular weight of the purified antibody.

BS079F:
DNA scale-up of the recombinant scFv-Fc antibody;
0.5 Liter transient production of the recombinant scFv-Fc antibody in CHO cells (7-day fed-batch cell culturing);
At least 2-step antibody protein purification;
Quality guarantee: SDS-PAGE >95%, SEC-HPLC >95%, and endotoxin <1 EU/mg. Mass spectrometry may be used to check molecular weight of the purified antibody.

BS079G:
DNA scale-up of the recombinant scFv-Fc antibody;
1 Liter transient production of the recombinant scFv-Fc antibody in CHO cells (7-day fed-batch cell culturing);
At least 2-step antibody protein purification;
Quality guarantee: SDS-PAGE >95%, SEC-HPLC >95%, and endotoxin <1 EU/mg. Mass spectrometry may be used to check molecular weight of the purified antibody.

BS079F-14-05:
DNA scale-up of the recombinant scFv-Fc antibody;
0.5 Liter transient production of the recombinant scFv-Fc antibody in CHO cells (14-day fed-batch cell culturing);
At least 2-step antibody protein purification;
Quality guarantee: SDS-PAGE >95%, SEC-HPLC >95%, and endotoxin <0.05 EU/mg. Mass spectrometry may be used to check molecular weight of the purified antibody.

BS079G-14-05:
DNA scale-up of the recombinant scFv-Fc antibody;
1 Liter transient production of the recombinant scFv-Fc antibody in CHO cells (14-day fed-batch cell culturing);
At least 2-step antibody protein purification;
Quality guarantee: SDS-PAGE >95%, SEC-HPLC >95%, and endotoxin <0.05 EU/mg. Mass spectrometry may be used to check molecular weight of the purified antibody.

Questions and Answers about the Recombinant scFv-Fc Antibody Production Services:

Question: Why do you use at least 2-step protein purification methods to purify recombinant scFv-Fc antibodies?
Answer: Protein A, G or L affinity chromatography is commonly used for antibody purification. However, for most antibodies, one-step purification is not enough to remove impurity, such as aggregate of the antibodies, endotoxin, and host cell protein or DNA residual. Impurity may interfere the in vivo and even in vitro activities of the purified antibodies. The impurity may vary lot to lot, and result from many factors. To minimize lot to lot difference, it is better to obtain high purity antibodies using multi-step purification methods.

Question: Is the yield from 14-day fed-batch cell culturing double that from 7-day cell culturing?
Answer: Generally speaking, yes. If not, it does not make much sense to do 14-day fed-batch cell culturing. Even double is not enough. Generally, we expect 2-10 folds of antibodies in the 14-day fed-batch cell culturing compared with the 7-day cell culturing.

Question: Our Fc is from a mouse IgG1. Are the prices the same as described above?
Answer: The cost of protein G purification is a little higher than protein A purification. The protein G resin is more expensive.

Question: We are doing high throughput screening (HTS) of a large number of recombinant scFv-Fc antibodies. Protein A one-step purification is enough. Can you do 30 ml, 10 ml or even 4 ml transient production?
Answer: Sure, please contact us.

Question: Compared to 3 or 4-day transient production, what is the advantage of 7-day and 14-day cell culturing programs?
Answer: More antibodies are produced from 7-day and 14-day cell culturing programs. Also, one can know better about the potential yield of a recombinant antibody molecule from 7-day and 14-day cell culturing programs.

We also provide the following antibody sequencing and production services:
Clone and sequence hybrimona antibody VH and VL
Construction, expression, and purification of whole IgG antibodies
Generation of stable cell lines expressing antibodies
scFv phage library construction service
ScFv Phage Library Screening Service