TABLE 1 

Outline of T. pallidum long-term-cultivation parameters

Parameter
Six-well cluster dishes (9 cm2/well)
No. of Sf1Ep cells/well, 1 × 105
Vol of TpCM-2 medium, 2 to 4 ml
Preincubation of medium and Sf1Ep cells in an atmosphere of 1.5% O2 and 5% CO2, with N2 making up the balance
Inoculation with 0.5–1.25 × 106 T. pallidum organisms per well, using triplicate wells per condition
Incubation for 6–7 days at 34°C in an atmosphere of 1.5% O2 and 5% CO2, with N2 making up the balance
Replacement of 50% of medium after 3–4 days (optional)
Trypsin/EDTA treatment of “donor” culture
Inoculation of “recipient” culture with 0.1 ml–0.5 ml of trypsinized “donor” culture
Subculture at 6–7-day intervals