Camelid Antibody Library Generation and Production
AbGenics provides specialized camelid antibody generation services against specific antigens provided by the clients. Antibodies libraries are generated from immunized camels and monoclonal antibodies isolated by phage display, screened and assayed for specific biological activity. The antibodies are purified by affinity chromatography and provided to end users in milligram quantities. The camelid antibody development takes place through the following steps:
- Immunisation of the camels : Antigen required, 4-5 mgs. A healthy animal 4-7 yrs old is immunised subcutaneously or intradermally with the antigen in adjuvant.
- Booster doses and final bleeding: Booster doses are given at 15, 30 and 45 days or 30, 45, 60 days depending on the antibody titer that is checked regularly and a final bleed of 60-100 ml done.
- Generation of the library : The lymphocytes are isolated and the cDNA prepared using oligonucleotides specific for camelid antibodies and a VHH library is prepared in E coli.
- Enrichment and panning of the library: Three rounds of enrichment by both positive and negative selection are done by phage display and final hits are isolated by ELISA and sequenced to confirm the presence of antibodies in the desired format.
- In vitro assays: The efficacy of the antibodies are determined by in vitro assays, that might be simple neutralisation assays for pathogens and binders for Immunohistochemistry applications. ADCC and CDC assays for complement development in case of full length antibodies and antimicrobial assays for assay of neutralising antibodies or cell based assays to determine its effects on regulatory pathways in cancers.
- Production and purification of the antibodies : The antibodies are produced in small amounts in bacteria/yeast systems, purified by affinity chromatography and supplied to the end users in mg quantities.