Method for large-scale production of lentivirus by using GMP-level serum-free suspension cells

A method for producing lentiviruses using cells in serum-free suspension culture, the method comprising:

• (a) providing packaging cells that grow in suspension;
• (b) inoculating the packaging cells in a first culture medium, wherein the first culture medium is a serum-free cell culture medium;
• (c) culturing the inoculated packaging cells, at conditions set at a temperature of 30-38° C., a dissolved oxygen concentration of 35-55%, a CO2 concentration of 2-10% and a pH of 6.9-7.4, and controlling dissolved oxygen and/or CO2 concentrations to maintain the pH between 6.9-7.4;
• (d) preforming a first liquid change when liquid change trigger conditions are met,
• wherein the liquid change trigger conditions comprise:
• (s1) the pH is ≤6.9;
• and
• (s2) a culture time is ≥72 hours;
• (e) repeating steps (c) and (d) n times, wherein n is 0, 1, 2, or 3;
• (f) performing transfection;
• (g) optionally carrying out post-transfection liquid change;
• (h) culturing the transfected packaging cells, at culture conditions set at a temperature of 30-37° C., a dissolved oxygen concentration of 35-55%, a CO2 concentration of 2-10% and a pH of 6.9-7.4, and controlling dissolved oxygen and/or CO2 concentrations to maintain the pH between 6.9-7.4.