title: Development of a measles vaccine production process in MRC-5 cells grown on Cytodex1 microcarriers and in a stirred bioreactor.
abstract: Measles vaccination remains the most efficient way to control the spread of the virus. This work focuses on the production of a measles vaccine using stirred conditions as an advanced option for process scale up. Non-porous Cytodex 1 microcarriers were used to support MRC-5 cell growth in suspension cultures. Virus replication was first optimized in spinner flasks, and the effects of various operational parameters were investigated. Cell infection with AIK-C measles strain at an MOI (multiplicity of infection) of 0.005, without glucose regulation and in M199 medium, resulted in a virus titer of 10⁶·²⁵ TCID₅₀ (median tissue culture infective dose)/ml. To optimize the production process in a 7-l bioreactor, we carried out various perfused cultures using minimum essential medium (MEM) + 5% FCS diluted with phosphate-buffered saline (PBS). We achieved a high cell density level (4.1 × 10⁶ cells/ml) with an efficient use of the medium when MEM + 5% FCS diluted with PBS at 25% was used during the cell amplification step. Optimization of measles production in MRC-5 cells grown on Cytodex 1 beads in a 7-l bioreactor showed that perfusion was the most efficient when compared to repeated-batch culture. Perfusion at a rate of 0.25 V (reactor volume)/day showed the highest specific productivity (1.6 IVP [infectious virus particle] cell⁻¹ day⁻¹). Testing of several stabilizers containing pharmaceutically improved components such as sugars, amino acids, and charged ions showed that the formulation composed of sucrose and MgCl₂, led to the maintenance of the infectivity of the AIK-C measles virus strain to a significant level, when stored at +28 °C, +4 °C and -60 °C.
authors.affiliation: Viral Vaccines Research and Development Unit, Institute Pasteur de Tunis, 13 Place Pasteur, BP74, 1002 Tunis Belvédère, Tunisia.
authors.forename: Khaled
authors.initials: K
authors.lastname: Trabelsi
authors.forename: Samy
authors.initials: S
authors.lastname: Majoul
authors.forename: Samia
authors.initials: S
authors.lastname: Rourou
authors.forename: Héla
authors.initials: H
authors.lastname: Kallel
mesh_terms: D019149:Bioreactors; D001709:Biotechnology / Q000379:methods; D018929:Cell Culture Techniques / Q000295:instrumentation / Q000379:methods*; D002460:Cell Line; D003470:Culture Media; D003911:Dextrans; D005347:Fibroblasts / Q000821:virology*; D006801:Humans; D008458:Measles Vaccine; D008459:Measles virus / Q000254:growth & development*; D008863:Microspheres; D014776:Virus Cultivation / Q000379:methods*; D014779:Virus Replication
chemical_list: D003470:Culture Media; D003911:Dextrans; D008458:Measles Vaccine; C052839:Cytodex