Fab Antibody Library Construction Service

Introduction of Fab Antibody Library Construction ServiceFab

Fab (antigen-binding fragment) is made from full-length antibody (e.g. IgG) by enzymatic or chemical digestion, the size is about 50 KDa, it is the antigen-binding domain of antibody molecule, which contains heavy chain variable region (VH), light chain variable region (VL), heavy chain 1 constant region (CH1), and light chain constant region (CL). Fab has many advantages, and it has a wide range of applications in the diagnosis and treatment of diseases. Fab is small in size, and can penetrate into tissues more effectively and be removed from blood faster. is small in size and can penetrate tissues more efficiently and is also cleared from the bloodstream more quickly. Fab does not interfere with anti-Fc mediated antibody detection due to the absence of Fc fragments. Due to its permeability, Fab antibody has become an indispensable tool for various research applications such as immunohistochemistry, immunofluorescence and flow cytometry.
Fab antibody-Alpha Lifetech

Alpha Lifetech Can Provide

With years of experience in recombinant antibody research, Alpha Lifetech provides professional Fab antibody library construction and preparation services. We can use two different methods to prepare Fab fragments. The first method is to enzymatically cleave the whole antibody, i.e., cleave the whole antibody with papain, pepsin and fusarium enzyme, etc. to form F(ab')2 fragments, and then reduce these fragments to obtain Fab fragments. Another method is to synthesize F(ab')2 antibody fragments by recombination, and then chemically reduce these fragments to obtain Fab. Currently, most recombinant antibody fragments are generated by phage display antibody libraries. Fab antibody libraries have obvious advantages: firstly, compared with the traditional and cumbersome monoclonal antibodies, fab antibody libraries can quickly and efficiently screen out Fab in a short time. antibodies in a short period of time. Second, like scFv antibodies, it is easier to generate Fab antibodies with higher affinity. Third, Fab fragments have the advantage of being highly stable under long-term storage conditions and compatible with commonly tested antisera.

Different types of antibody libraries	Display system for different antibody libraries	Phage particle	Host bacteria	Human or animal source	Tissues or cells
Fab native library	Yeast display, ribosome display, mammalian cell display, phage display	PMECS, pComb3X and pCANTAB 5E	TG1 E. coli, XL1-Blue and ER2738	People, rats, rabbits, sheep, cattle	Spleen, PBMC in humans or other animals, hybridomas
Fab immune library
Fab synthesis library
Fab semi-synthetic library

Fab Antibody Library Construction Service Process

The Fab antibody library constructed by Alpha Lifetech is rich in variety and large in size, and will be screened to find the ideal antibody for our customers. We have a mature Fab antibody library construction system, which can construct Fab antibody libraries on human and various animals, including immune libraries, natural libraries, semi-synthetic libraries, synthetic libraries and so on, which can meet the different needs of customers. The Fab antibody libraries we can construct include phage libraries, ribosomal libraries, mRNA display libraries, yeast cell libraries, mammalian cell libraries and bacterial libraries, etc., among which, the phage display libraries are the ones that are most demanded by customers. We have a variety of phage platforms including M13, T4, T7 and λ phage, which can meet the different needs of customers and provide personalized Fab phage library construction services. Our researchers have many years of experience in phage library construction, and have constructed Fab libraries up to 1010 in size with rich diversity, which greatly increases the possibility of generating high-affinity Fab antibodies. The Fab antibodies we prepare can be directed against different antigens, such as viruses, bacteria, toxins, receptors and tumor antigens, peptides and so on. Hybridoma technology has the disadvantages of cumbersome operation, long cycle time, easy contamination and high immunogenicity. Phage antibody display technology is easy to operate, short experimental cycle, low environmental requirements, and can express Fab antibodies in large quantities by prokaryotic expression system. We provide a variety of phage vectors including PMECS, pComb3X and pCANTAB 5E to meet the different needs of customers. We also provide a variety of host bacteria such as TG1 E. coli, XL1-Blue and ER2738 to meet the needs of our customers. Alpha Lifetech will provide comprehensive Fab library construction services to meet the different needs of researchers at home and abroad. Our goal is to understand and satisfy the recombinant antibody preparation needs of different customers and assist in solving any problems in research work.

Fab Antibody Library Construction Service Workflow

Steps	Specification	Timeline
Step1: Fab preparation	Method 1: The whole antibody was cleaved with papain, pepsin and fusarase to form F(ab')2 fragments, which were then reduced to obtain Fab fragments.	14 days
	Method 2: F(ab')2 antibody fragments were synthesized by recombination, and then these fragments were chemically reduced to obtain Fab.
Step2: Enzymatic cleavage and ligation	The Fab gene was digested and ligated with T4 DNA ligase	1 day
Step3: Plasmid transformation	Primary Fab antibody libraries are obtained by electrochemical or chemical transformation	3 days
Step4: Fab library diversity determination and PCR validation	The libraries were titrated and library size was calculated; positive clones were tested by PCR	2 days