Amended recombinant cells (ARCs): an economical and surprisingly effective production and delivery vehicle for recombinant bovine IFN-gamma.
Recombinant Pseudomonas fluorescens cells, expressing over 40% protein as bovine interferon-gamma (IFN-gamma), were chemically fixed to sterilize the culture and amend the bacterial cell wall. When killed and fixed recombinant cells, termed here amended-recombinant-cells (ARCs), were assayed for interferon activity, we obtained the following surprising results: 1) sterilization and fixation did not inactivate ARC-encapsulated IFN-gamma; 2) ARC-encapsulated IFN-gamma and soluble, recombinant IFN-gamma were equally active in vitro but proteolysis was required for release of the ARC cytokine; and 3) ARC-encapsulated IFN-gamma was active in vivo with optimal adjuvant activity at a dose about 1000-fold less than previously reported for soluble, recombinant IFN-gamma and 100-fold less than doses which induced adverse systemic effects. The mechanism by which ARC-encapsulation increased IFN-gamma activity in vivo remains uncertain. However, our in vitro results show that sustained release of soluble IFN-gamma is a likely factor. The ARC production and delivery system achieves enhanced adjuvant activity with reduced risk of systemic effects, and the low cost of IFN-gamma production offers new opportunities for the use of this important cytokine.
Gaertner
Frank H
FH
Babiuk
Lorne A
LA
Van Moorlehem
Elaine A
EA
Beskorwayne
Terry K
TK
Lee
Stacey L
SL
Shutter
Robert W
RW
Armstrong
Janna M
JM
Griebel
Philip J
PJ
D000818:Animals; D000998:Antiviral Agents / Q000008:administration & dosage*; D015153:Blotting, Western; D002417:Cattle; D002473:Cell Wall / Q000737:chemistry; D002986:Clinical Trials as Topic; D003001:Cloning, Molecular; D016207:Cytokines / Q000008:administration & dosage; D016503:Drug Delivery Systems / Q000191:economics / Q000662:veterinary; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D005802:Genes, MHC Class II; D006242:Haptoglobins / Q000096:biosynthesis; D007371:Interferon-gamma / Q000008:administration & dosage* / Q000096:biosynthesis*; D008297:Male; D011550:Pseudomonas aeruginosa / Q000378:metabolism*; D011994:Recombinant Proteins; D013242:Sterilization; D014721:Vesicular stomatitis Indiana virus / Q000187:drug effects; D010948:Viral Plaque Assay
D000998:Antiviral Agents; D016207:Cytokines; D006242:Haptoglobins; D011994:Recombinant Proteins; D007371:Interferon-gamma