title: A microcarrier culture method for the production of large quantities of viable Chlamydia pneumoniae.
abstract: We studied the propagation of Chlamydia pneumoniae strain TW-183 in HEp2 cells grown on microcarrier beads. Infection of the cells in microcarrier culture was optimized by addition of 7.5% polyethylene glycol 4000 (PEG4000) during adsorption. The yield in microcarrier culture was similar to that of microtitre-plate culture using centrifugation-assisted infection (120 x 10(6) and 225 x 10(6) bacteria/10(6) HEp2 cells respectively), as was the burst size (505 and 449 bacteria produced/infecting bacterium respectively). However, up to 64% savings in labour time and 27% saving in culture medium were achieved if the microcarrier culture method was used instead of the microtitre-plate culture method. The optimal yield of viable bacteria could only be achieved at a narrow range of multiplicities of infection (0.24 - 1.14 inclusion-forming units/cell), independent of the mode of infection (centrifugation-assisted infection of PEG4000-facilitated infection by adsorption) and independent of incubation temperature (35 degrees C or 37 degrees C). The yield of microcarrier cultures was the same at an incubation temperature of 35 degrees C or 37 degrees C in contrast to an increased production at 35 degrees C in the microtitre-plate culture method using centrifugation-assisted infection. In conclusion, the microcarrier culture method is useful to produce large quantities of viable Chlamydia pneumoniae economically.
authors.affiliation: National Institute of Public Health and The Environment, Department of Virology, Bilthoven, The Netherlands.
authors.forename: A
authors.initials: A
authors.lastname: Meijer
authors.forename: C E
authors.initials: CE
authors.lastname: Vallinga
authors.forename: J M
authors.initials: JM
authors.lastname: Ossewaarde
mesh_terms: D016993:Chlamydophila pneumoniae / Q000254:growth & development*; D005285:Fermentation; D006801:Humans; D014407:Tumor Cells, Cultured