Table 5.

DOE studies investigating CHO cell expansion.

Experimental Design	Number of Factors	Factors	Year	Ref.
Full factorial 23	3	Glucose, Glutamine, Inorganic salts	2004	[72]
Full factorial 25	5	Feed volume at days 3, 5, 7, 10, and 12	2019	[73]
25−1 Resolution V	5	Sodium hypoxanthine-thymidine, Antioxidant, ITS 1, Fatty acids supplement, Polyamines supplement	2006	[74]
24−1 Resolution IV	5	Amino acid feed, Glucose Feed, Temperature, pH	2011	[96]
Full factorial 31 × 22	3	Glucose feed, Temperature shift, pH control frequency
Plackett–Burman	20	BSA, Transferrin, Insulin, Sodium pyruvate, Putrescine, Glucose, Ala, Arg, Asn, Asp, Cys, Gln, Glu, Gly, Ser, Met, (Pro, His, Hydroxyproline), (Thr, Val, Ile), (Leu, Trp, Lys), (Phe, Tyr)	1992	[75]
Plackett–Burman	4	Oleic acid, Linoleic acid, Cholesterol, (Choline, Ethanolamine)	1995	[76]
Plackett–Burman	21	Ala, Arg, (Asn, Asp), Cys, Gln, Glu, Gly, Ser, Met, (Phe, Tyr), (Thr, Val, Ile), (Leu, Trp, Lys), (Pro, His), Insulin, Transferrin, Ethanolamine, Pluronic F68, Phosphatidylcholine, Putrescine, Linoleic acid, Hydrocortisone	1998	[77]
Plackett–Burman	21	Ala, Arg, (Asn, Asp), Cys, Gln, Glu, Gly, Ser, Met, (Phe, Tyr), (Thr, Val, Ile), (Leu, Trp, Lys), (Pro, His), Insulin, Transferrin, Ethanolamine, Pluronic F68, Phosphatidylcholine, Hydrocortisone, Sodium selenite, Glutathione	1999	[78]
Plackett–Burman	21	Ala, Arg, (Asn, Asp), Cys, Gln, Glu, Gly, Ser, Met, (Phe, Tyr), (Thr, Val, Ile), (Leu, Trp, Lys), (Pro, His), Sodium selenite, Insulin, Transferrin, Hydrocortisone, Ethanolamine, Phosphatidylcholine, Glutathione, Pluronic F68	1999	[79]
RSM	2	Glucose, Gln	2005	[80]
RSM	2	Glucose, NaCl
27−3 Resolution IV	7	Insulin, Meat peptone, Yeast extract, SerEx, BSA, Linoleic acid–BSA, Dextran sulfate	2006	[81]
RSM	2	Insulin, SerEx
RSM	5	Gln, Essential amino acids supplement, Non-essential amino acids supplement, ITS 1, Lipids	2007	[82]
RSM	3	Yeastolate, Soy, Wheat	2009	[83]
Plackett–Burman	17	Ethanolamine, Sodium selenite, Putrescine, Hydrocortisone, Lipids, Sodium pyruvate, Ascorbic acid, Glutathione, Choline chloride, D-calcium pantothenate, Folic acid, Niacinamide, Pyridoxine-hydrochloride, Riboflavin, Thiamine hydrochloride, Cyanocobalamin, I-inositol	2013	[84]
RSM	3	Lipids, Putrescine, Ammonium ferric citrate
RSM	3	Temperature, pH, Seeding density, Culture duration	2013	[85]
RSM	3	Glucose, Asn, Gln	2015	[86]
Plackett–Burman	19	19 amino acids (Gln excluded)	2015	[87]
RSM	4	Asp, Glu, Arg, Gly
RSM	3	pH, O2 tension, CO2 tension	2017	[88]
28−4 Resolution IV	8	8 kinds of commercial supplements	2020	[89]
RSM	4	4 kinds of commercial supplements
Full factorial 23	3	3 kinds of commercial supplements
Plackett–Burman	8	Sodium selenite, Transferrin, Albumin, Insulin, Tocopherol, Tween 80, Fatty acids, Synthetic cholesterol	2019	[90]
Box–Behnken RSM	3	Transferrin, Insulin, Tween 80
Plackett–Burman	15	Gln, Asp, Lys, Trp, Thr, Val, His, Vitamin B1, Thymidine, Deoxy-cytidine, 3-methyl-oxobutyrate, Deoxy-guanosine, Vitamin B6, Vitamin A, Arachidonate	2020	[91]
RSM	2	Thr, Arachidonate
Mixture Design	6	Hexoses, Energy provider compounds	2007	[92]
Mixture Design	20	20 amino acids	2013	[97]
Mixture Design	43	19 amino acids (Gln excluded), Disodium phosphate, Magnesium sulfate, Calcium chloride, Myo-inositol, Sodium pyruvate, D-biotin, Choline Chloride, Folic acid, Niacinamide, D-pantothenic acid, Potassium chloride, Pyridoxine, Riboflavin, Thiamine, Ferric ammonium citrate, Vitamin B12, Hypoxanthine, Thymidine, Putrescine, Ethanolamine, Zinc sulfate, Cupric sulfate, Pluronic, Sodium selenite	2013	[93]
DSD	5	pH, Shifted temperature, Seeding density, Viable cell density at first feeding, Viable cell density at temperature shift	2019	[94]
DSD	6	DMEM fraction, Cellgro trace element A, Cellgro trace element B, Insulin, Ca2+, Mg2+	2021	[95]

¹ ITS supplement contains sodium selenite, bovine insulin, and human transferrin.