NaCS‐PDMDAAC immobilized cultivation of recombinant Dictyostelium discoideum for soluble human Fas ligand production

Abstract

Dictyostelium discoideum is a promising eukaryotic host for the expression of heterologous proteins requiring post-translational modifications. However, the dilute nature of D. discoideum cell culture limits applications for high value proteins production. D. discoideum cells, entrapped in sodium cellulose sulfate/poly-dimethyl-diallyl-ammonium chloride (NaCS-PDMDAAC) capsules were used for biosynthesis of the heterologous protein, soluble human Fas ligand (hFasL). Semi-continuous cultivations with capsules recycling were carried out in shake flasks. Also, a scaled-up cultivation of immobilized D. discoideum for hFasL production in a customized vitreous airlift bioreactor was conducted. The results show that NaCS-PDMDAAC capsules have desirable biophysical properties including biocompatibility with the D. discoideum cells and good mechanical stability throughout the duration of cultivation. A maximum cell density of 2.02 × 10(7) cells mL(-1) (equivalent to a maximum cell density of 2.22 × 10(8) cells mL(-1) in capsules) and a hFasL concentration of 130.40 μg L(-1) (equivalent to a hFasL concentration of 1434.40 μg L(-1) in capsules) were obtained in shake flask cultivation with capsules recycling. Also, a maximum cell density of 1.72 × 10(7) cells mL(-1) (equivalent to a maximum cell density of 1.89 × 10(8) cells mL(-1) in capsules) and a hFasL concentration of 106.10 μg L(-1) (equivalent to a hFasL concentration of 1167.10 μg L(-1) in capsules) were obtained after ∼170 h cultivation in the airlift bioreactor (with a working volume of 200 mL in a 315 mL bioreactor). As the article presents a premier work in the application of NaCS-PDMDAAC immobilized D. discoideum cells for the production of hFasL, more work is required to further optimize the system to generate higher cell densities and hFasL titers for large-scale applications.

Cellulose-Based Gels

“…Cellulose sulfate is another ionic cellulose derivative that can be used for the formation of PECs with various natural or synthetic polycations, such as chitosan and poly‐dimethyl‐diallyl‐ammonium chloride (PDMDAAC). The PECs have the advantages of physiochemical stability, robust mechanical strength, good biocompatibility, and sharp cut‐off membranes, and can be used in drug delivery and cell immobilization. Solution casted poly(ethyleneimine)/cellulose sulfate PEC films have been used as controlled release matrices for pamidronate.…”