populations cultured in FCS in mice and humans Bovine apolipoprotein B-100 is a dominant immunogen in therapeutic cell

Abstract Recent studies have demonstrated that cell populations intended for therapeutic purposes that are cultured in heterologous animal products can acquire xenoantigens, potentially limiting their utility. In investigations of the immune response to murine embryonic stem (ES) cells, we found that a strong antibody response was generated after the second infusion. Both polyclonal and monoclonal antibody responses, derived from immunized mice, were found to be specific for bovine apolipoprotein B-100 which binds to abundant low density lipoprotein receptor on the cell surface and is internalized. Here we have shown that in the majority of patients administered three different types of cell-based therapies utilizing cells grown in FCS containing media, an antibody response to bovine apoB-100 develops following the second infusion and is the dominant specificity. The known and potential clinical effects of such antibodies are discussed. Introduction Cellular therapies are of increasing interest for repair or replacement of damaged or destroyed tissues. While the pluripotentiality of embryonic stem (ES) cells is considered very attractive for tissue replacement