Preparation of heavy chain polyclonal antibody against zinc transporter SLC39A6 and its diagnostic application

Background: SLC39A6 Protein (solute carrier family 39) or LIV-1 is a zinc transporter protein that is overexpressed in positive estrogen cancers such as breast cancer. The LIV-1 protein transfer zinc into the cytoplasm through the plasma membrane. Today it is known that just as a decrease in the concentration of zinc in the cell can cause cancer, an excessive increase in the concentration of zinc can also stimulate irregular cell division and caused cancer. Thus, inhibition of zinc transporter protein may play a role in preventing malignancies and metastasis. It can also be used as a diagnostic marker in the diagnosis of cancers in various laboratory methods. The present study was performed to prepare a polyclonal camel antibody for the detection of LIV-1 protein at the cell surface. Methods: This study was started in the Pasture Institute of Iran in 2018 September and finished in February 2020. An expression construct containing the human LIV-1 gene was prepared and transferred to the E.coli BL21 by chemical (CaCl2) and heat shock method. The expression of the protein was induced by IPTG and then protein was purified by affinity (Ni-NTA) chromatography. After preparing recombinant protein one female camel was immunized, 6 times at two weeks intervals with Freund's adjuvant. After immunization, the isolated polyclonal antibody was evaluated by ELISA, western blotting and flow cytometry in the detection of LIV-1 protein. Results: The result showed that LIV-1 protein was well purified and also the camel polyclonal antibody was able to detect LIV-1 protein in ELISA, western blot and also it can detect LIV-1 on the cell surface as shown by flow cytometry test. Conclusion: In recent years, LIV-1 has been shown to be a good candidate as a marker in breast cancer, so polyclonal antibodies against LIV-1 can be used for early detection of breast cancer by various diagnostic methods. In this study, it has been shown that polyclonal camel antibodies can be used in laboratory methods and can be considered for immunological tests and therapeutic applications.