HUMAN CD46, CD55 AND CD59 EXPRESSION INFLUENCE ON SWINE TRANSGENIC FETAL FIBROBLASTS' SURVIVABILITY IN THE PRESENCE OF HUMAN COMPLEMENT COMPONENTS

Mechanisms regulating the activity of the complement system responsible for the rejection of transplant organs are balanced so that the attack is instantaneous but is restricted to the infected cells of the organism. The most important components regulating its activity comprise CD55 and CD46 factors as well as the CD59 anchored in the cell membrane. Hyperacute response of the immunological system appears to be the key in the xenotransplant rejection and the elaboration of methods preventing its occurrence will give a real chance for the development of xenotransplantation. Gene constructs containing coding sequences of human CD46, CD55 and CD59 were prepared and used to transfect porcine fetal fibroblasts. Stable lines were molecularly characterized for an integration of transgenes by PCR. Lines with a stable integration of transgenes were subjected to further characterization of expression by RT-PCR and vitality test. Molecular characteristics of the transgenic cell lines obtained revealed a steadfast integration and, in the majority of cases, expression of the introduced transgenes. The performed cytotoxicity analysis demonstrated that transgenic lines were characterised by a higher survivability rate than non-transgenic cells in the presence of human serum which proved their protective influence in relation to the activity of the complement system.