TY - JOUR
T1 - Properties of Trichomonas vaginalis grown under chemostat controlled growth conditions
AU - Lehker, M. W.
AU - Alderete, J. F.
PY - 1990
Y1 - 1990
N2 - Trichomonas vaginalis isolates NYH 286 and IR 78 were grown in continuous flow culture conditions in a complex trypticase-yeast extract-maltose medium supplemented with heat-inactivated horse serum. Parasites could be stably maintained in the chemostat at high densities ranging from 1 x 106 to 1 x 107 organisms ml-1. Growth densities, acid production, and profiles of total versus secreted trichomonad proteins were characterised at different rates of growth and pH. Growth rate influenced the extent of parasite production of acid and the shedding of proteins into the medium but had no effect on overall parasite density. Lowering the pH from 6.0 to 5.0 resulted both in a decrease of cell density and acid production. At pH 4.5 isolate IR 78 but not NYH 286 was capable of growth and multiplication, showing the ability of some isolates to survive at the vaginal pH of healthy individuals. At this lower pH, however, isolate NYH 286 but not IR 78 synthesised new proteins which were detectable in stained gels. Also, inoculation of the chemostat with isolate NYH 2386 comprising a mixture of fluorescent (positive, pos) and nonfluorescent (negative, neg) trichomonads as defined by monoclonal antibody reactivity to a surface immunogen resulted in a change in the parasite population to an almost homogeneous neg phenotype. These neg phenotype organisms switched back to pos phenotype after transfer to test tubes.
AB - Trichomonas vaginalis isolates NYH 286 and IR 78 were grown in continuous flow culture conditions in a complex trypticase-yeast extract-maltose medium supplemented with heat-inactivated horse serum. Parasites could be stably maintained in the chemostat at high densities ranging from 1 x 106 to 1 x 107 organisms ml-1. Growth densities, acid production, and profiles of total versus secreted trichomonad proteins were characterised at different rates of growth and pH. Growth rate influenced the extent of parasite production of acid and the shedding of proteins into the medium but had no effect on overall parasite density. Lowering the pH from 6.0 to 5.0 resulted both in a decrease of cell density and acid production. At pH 4.5 isolate IR 78 but not NYH 286 was capable of growth and multiplication, showing the ability of some isolates to survive at the vaginal pH of healthy individuals. At this lower pH, however, isolate NYH 286 but not IR 78 synthesised new proteins which were detectable in stained gels. Also, inoculation of the chemostat with isolate NYH 2386 comprising a mixture of fluorescent (positive, pos) and nonfluorescent (negative, neg) trichomonads as defined by monoclonal antibody reactivity to a surface immunogen resulted in a change in the parasite population to an almost homogeneous neg phenotype. These neg phenotype organisms switched back to pos phenotype after transfer to test tubes.
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U2 - 10.1136/sti.66.3.193
DO - 10.1136/sti.66.3.193
M3 - Article
C2 - 2370063
AN - SCOPUS:0025309496
VL - 66
SP - 193
EP - 199
JO - Sexually Transmitted Infections
JF - Sexually Transmitted Infections
SN - 1368-4973
IS - 3
ER -