Phage Display Service Introduction

Phage display, as a molecular technique based on the genetic modification of phage DNA, has become a molecularly powerful tool to generate molecular probes against specific targets by presenting these fragments on the phage surface and thus selecting peptide/antibody fragments with specific binding properties from a large number of variants (libraries). And phage display technology has the following advantages:
1. Phage display is easy to operate, low cost and takes only a few weeks time.
2. Phage display has a large screening range of 107-109.
3. Phage display is suitable for operation at the gene level, so that the gene and phenotype can be unified.
4. Phage display antibodies can be selected for multiple cycles of elution and can be stored for long periods of time
5. Phage display allows for the production of humanised antibodies with higher utilisation value.

Our Phage Display System

 The main information of the M13/ T4/ T7 phage display system is shown in Table 1. 

Alpha Lfetech Can Provide

Phage Display unifies genotype and phenotype into one, combining selectivity and amplification with powerful screening capabilities. Alpha Lifetech can provide a wide range of services for phage display antibody development.
The main services include: VHH antibody library platform, scFv antibody library platform, Fab antibody library platform, phage library construction platform, phage library screening platform and antibody humanisation service and other services.

Phage Display Antibody Development Process

1. Total RNA or mRNA is extracted from peripheral blood or lymphoid tissue;
2. To reverse transcription of RNA into first-strand cDNA using random six-base primers;
3. We use cDNA to amplify the protein gene, and design multiple primer combinations to replicate and amplify the light chain V fragment gene and the heavy chain V fragment gene, respectively, from the cDNA library;
4. We used overlap PCR to splice the light chain V fragment gene and heavy chain V fragment gene sequences into one piece
5. The successfully ligated light and heavy chains are integrated into the phage vector;
6. Phage plamid successfully ligated with exogenous protein genes were introduced into E. coli host bacteria;
7. We use helper phages to superinfect the host bacteria;
8. The phage initiates roll replication, generating single-stranded DNA and replicating the capsid protein;
9. Phage assembly is completed and phage maturation is released from the host cytoplasm into the environment;
10. Elution of the phage library.

Fig. 3 Phage display antibody synthesis process