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Fig. 2. C. difficile toxin B completely inhibits EC morphogenesis in both
collagen and fibrin matrices. (A) Photographs of three-dimensional cultures
fixed and stained with toluidine blue. ECs were allowed to undergo
morphogenesis in collagen and fibrin matrices for 8, 24 or 48 hours as
indicated. Arrowheads indicate vacuoles; arrows indicate developing lumins.
Cells pretreated with toxin B are shown in lower panel. Note the complete lack
of vacuoles and lumenal structures in toxin B group. Quantification of cells
forming vacuoles and lumens in three-dimensional collagen (B) and fibrin
matrices (C). Cultures were fixed and stained at various time points following
pretreatment with toxin B and C3 ribosyltransferase (collagen only). Data are
expressed as a percentage of cells forming vacuoles±s.d.
(n=3). Bar=30 µm.