Induction of Immunological Tolerance in Chicken ( Galius domesticus) to DT40 Cells Stably Transfected with GFP

Genetically modified cells expressing xenogeneic proteins may trigger strong immunological responses when introduced into animals; however, these responses may be prevented by inducing immunological tolerance. In this study, we have introduced allogeneic cells into chicken embryos via embryonic blood vessel microinjection and induced immunological tolerance to them. Chicken DT40 cells stably transfected with the GFP gene (DT40-GFP cells) were produced and used as antigens to induce immunological tolerance by this method at 65-70 h of incubation for preimmunization. Enzyme-linked immunosorbent assays and lymphocyte proliferation assays were performed to determine the serum antibody and lymphocyte responses in hatched chickens after reinjection of the cells at 6 weeks post hatching. Our findings indicated that humoral and cellular immunological responses to allogeneic DT40 cells and DT40-GFP cells expressing xenogeneic proteins can be suppressed by preimmunization during embryogenesis; moreover, an effect on lymphocyte proliferation was observed.