Construction of single domain camel antibody library against breast cancer cellular antigens

VHH (Nanobody) is a camel antibody and is the smallest unit binding to antigen. The small size of nanobodies is the greatest advantage that makes easy genetic manipulation of them. The main aim of this study was construction of a single domain antibody library from camel immunized with human breast adenocarcinoma-SKBR3 cell line. At first, in this experimental study, SKBR3 cell extract was subcutaneously injected to a camel in three rounds. Then, total RNA was extracted from spleen of camel and VHH fragments synthesized and amplified using RT-PCR method. The VHH fragments were inserted into Pcomb3X phagemid and recombinant constructs were electroporated into DH5α bacteria. Diversity of provided library was studied by enzymatic fingerprinting techniques. Finally, VHH expression was analyzed by SDS-PAGE. In this study, a camel antibody library with 105 colonies was constructed. Also, the enzymatic fingerprinting showed a high diversity in this antibody library. Primary studies by SDS-PAGE showed that VHH protein with a molecular weight of 15 kDa is expressed in transformant bacteria. Providing an immune antibody library against SKBR3 cell line makes an option for isolation of specific VHH antibodies against different breast cancer antigens.