(157n) Tobacco Cell-Secreted Hematopoietic Growth Factors for Ex Vivo Production of Red Blood Cells | AIChE

(157n) Tobacco Cell-Secreted Hematopoietic Growth Factors for Ex Vivo Production of Red Blood Cells

Authors 

Xu, J. - Presenter, Arkansas State University
Ex vivo generation of clinically available red blood cells (RBCs) from hematopoietic stem cells (HSCs) represents a promising approach for overcoming the limitations associated with the use of donor’s blood. Both expansion and differentiation of HSCs are highly reliant on erythropoietic growth factors (eGFs). This project aims to develop a novel plant cell-based bioproduction platform for eGFs at significantly reduced cost. In addressing the low productivity bottleneck of plant cell culture technology, we are engineering hydroxyproline (Hyp)-O-glycosylated peptides (HypGPs) that function as a molecular carrier to boost the secretion of fused proteins from culture plant cells. Each of three key eGFs essential for HSCs expansion and differentiation, erythropoietin (EPO), stem cell factor (SCF) and interleukin 3 (IL-3), were expressed in tobacco BY-2 cells as fusion with a strategically designed HypGP tag, for example (SP)20 consisting of 20 tandem repeats of a “Ser-Pro” motif. The secreted protein yields were up to 500-fold greater than the expression of eGF controls lacking a HypGP tag. The HypGP-tagged eGF secreted from plant cells exhibited the bioactivity in stimulating the proliferation of TF1 erythroleukemic cell. Furthermore, the plant cell-derived eGFs were able to stimulate the expansion and differentiation of umbilical cord blood-derived CD34+ cell towards RBCs. This project provides a new and cost-effective bioproduction platform for eGFs, facilitating manufacturing of HSCs-derived RBCs at large scale for clinical applications.