Comparison of virulent trypomastigotes with low-virulent ones derived from a single strain of Trypanosoma cruzi: infectivity to new fibroblasts from various organs of the mouse.
Previous experiments have shown that the infectivity of virulent trypomastigotes in L-cell culture was much more intensive not only for macrophages but also for newly cultured fibroblasts from the mouse heart as compared to low-virulent trypomastigotes in L-cell culture which had been derived from the same strain. On the other hand, the infectivity of virulent trypomastigotes for L-cells was less intensive. In the present work, new fibroblasts derived from muscles, skin, heart and kidney of newborn mice and established fibroblasts from mouse muscles were examined in terms of their susceptibility to trypomastigotes of different virulence. A slight difference of susceptibility to virulent trypomastigotes among new fibroblasts from different sources was found, i.e. fibroblasts derived from muscles and skin were more susceptible than those from heart and kidney. Growth of low-virulent trypomastigotes was suppressed in all new fibroblasts. This suppression was explained by the result that amastigote proliferation of a low-virulent strain was much slower in new fibroblasts from mouse muscles in spite of a similar penetrative ability of both kinds of trypomastigotes. Furthermore, a slight decrease in the susceptibility of new fibroblasts to virulent trypomastigotes was found depending on the length of time fibroblasts had been maintained.
Kanbara
H
H
Dept. of Protozoology, Nagasaki University, Japan.
Yanagi
T
T
Nakazawa
S
S
Fukuma
T
T
D000818:Animals; D000831:Animals, Newborn; D002478:Cells, Cultured; D005347:Fibroblasts; D006321:Heart / Q000469:parasitology*; D007668:Kidney / Q000469:parasitology*; D051379:Mice; D008813:Mice, Inbred ICR; D009132:Muscles / Q000469:parasitology*; D012867:Skin / Q000469:parasitology*; D014349:Trypanosoma cruzi / Q000472:pathogenicity*; D014774:Virulence