Exploitation of human CD99 expressing mouse myeloma cells as immunogen for production of mouse specific polyclonal antibodies

- The human recombinant CD99 were stably expressed on mouse myeloma cells.
- The myeloma cells expressing CD99 were used as immunogen for mouse immunization.
- The produced antibodies react to human recombinant CD99 and native CD99 molecules.
- The produced antibodies were IgG isotype and the titer was higher than 1:400.
- This method is valuable for polyclonal antibody production to CD99 molecules.

In this study, we describe the application of a molecular biology technique for the production of mouse polyclonal antibodies (pAbs) specific to human cell surface molecules. Production of the pAb specific to the human CD99 surface molecule was used as the study model. The retroviral expression system was employed to generate human CD99 expressing mouse myeloma cells. After cell sorting and single cell cloning, a myeloma clone which stably expressed high levels of human CD99 on its surface was established. The human CD99 expressing mouse myeloma cells were then used as the immunogen for immunization of BALB/c mice. As endogenous proteins of mouse myeloma cells possess self-non-immunogenicity for BALB/c mice, after immunization, only the expressed human CD99 molecules induce antibody response. After three immunizations, high titers of mouse anti-CD99 pAbs were successfully produced. The produced pAb specifically reacted to both recombinant human CD99 and native CD99 molecules expressed on human blood cells. The established technology is simple and valuable for the production of pAbs specific to human CD99 membrane proteins which can be used for characterization of the CD99 molecule.