Monoclonal antibody production includes hybridoma technology, phage display technology, single-cell technology, and transgenic mouse technology. The value of the phage display antibody discovery platform is expected to reach 892 million US dollars by 2024 and 1.335 billion US dollars by 2031, with a growth rate of up to 5.9%. It mainly includes T4 phage, T7 phage, λ phage, and filamentous phage display systems, which have great prospects for basic research, clinical diagnosis, and biological agent development. In 2024, the global hybridoma antibody discovery platform is expected to be worth 729 million US dollars and is expected to reach 1.1 billion US dollars by 2031, with an increase of 6.1%. The main types include mouse hybridoma, rat hybridoma, and rabbit hybridoma, which have great value in basic research, clinical diagnosis, and biopharmaceutical development.

Fig. 2: Phage Display-Based Antibody Discovery Market Size Trend and Proportion.

Alpha Lifetech has a monoclonal antibody development platform, and experienced scientists can customize corresponding antibody development plans according to customer needs. Our monoclonal antibody production technologies include hybridoma technology, phage display technology, and single-cell technology. With over 2000 successful project experiences and knowledge reserves in antibody preparation, we accelerate the progress of customer project development.

Native library, also known as Natural library, is constructed by cloning antibody gene fragments of natural non-immune B lymphocytes, mainly VH-CH and VL-CL fragments. The native library contains a large number of antibody sequences that have not been exposed to antigens or screened by the immune system. Therefore, a single library can bind multiple antigens (proteins, peptides, etc.), and it has a wide range of antigen-binding potential and diversity.

The immune library immunizes animals with specific antigens, extracts lymphocytes from immunized animals, extracts RNA and synthesizes cDNA, constructs corresponding vectors, and transfects them into Escherichia coli. With the participation of auxiliary bacteriophages, the immune library is generated. Due to the specific antigen immunization of the immune library, it only targets a single antigen and has certain limitations on a wide range of antigen screening.

A synthetic library is a library composed of antibody variable region sequences designed and synthesized based on structure and function. The library has high randomness and diversity, and antibodies that are difficult to screen may not be screened by animal immunity. However, due to the lack of synthesis in vivo, the corresponding antibody expression level may be low and easily degraded, so comprehensive consideration is needed.

A semi-synthetic library is composed of a designed variable region sequence and a natural sequence. Based on the advantages of artificial design and natural libraries, semi-synthetic libraries reduce the problem of low expression levels caused by fully synthetic libraries and correspondingly increase the recognition sites of this library. For antibodies that are difficult to immunize in vivo, the success rate of screening this library will increase.

Tab 3: Alpha Lifetech Can Provide Types of Antibody Libraries

Extract total RNA from lymphocytes (such as human peripheral blood lymphocytes, lymph node cells, or spleen cells). Reverse transcribe mRNA into cDNA using reverse transcription technology. Specific primers were designed, cDNA was used as a template, variable region genes of antibodies were amplified by PCR, PCR products were separated by agarose gel electrophoresis, and target gene fragments were recovered. Cloning the target gene fragment into a phagemid vector, usually by enzyme digestion and ligation, the gene fragment is connected to the vector, and the ligation product is electroporated into competent E. coli cells to construct an E. coli library containing the target antibody fragment. Coat the transformed cells on agarose culture plates for overnight growth, then scrape off the cells and store them in glycerol to form a bacterial library. Expand the cells in the bacterial library, cover them with auxiliary bacteriophages, and display target antibody fragments on the surface of the bacteriophages. Collect the supernatant, i.e., the phage display library. Subsequently, phage library rescue was carried out, and after three rounds of specific target screening (liquid phase screening, solid phase screening, and cell screening), high-affinity antibody sequences were obtained. NGS sequencing was performed to select the optimal antibody sequences for expression and validation, and the corresponding antibodies were obtained.

Fig 3: Phage display library construction and screening process

With the increasing market share of monoclonal antibody drugs, the market value of the technology for producing monoclonal antibodies is also increasing year by year. Monoclonal antibody therapy dominates, and the immune checkpoint is an effective means of cancer treatment. For corresponding targets, our company also has corresponding biosimilar antibodies for basic research use. Our antibodies have undergone batch validation and functional verification, aiming to provide customers with good antibody choices.

[1] Lu, RM., Hwang, YC., Liu, IJ. et al. Development of therapeutic antibodies for the treatment of diseases. J Biomed Sci 27, 1 (2020). https://doi.org/10.1186/s12929-019-0592-z