Fig. 6

Igsf11 promotes aggregation of K562 myeloid leukemia cells in vitro.

Cells were transfected with wild-type zebrafish igsf11 (A, B), S151P, seurat^utr15e1 mutant igsf11 (C, D), T29P, seurat^wp15e2 mutant igsf11 (E, F), or mock transfected (G, H). At the start of the experiment, the numbers of small cellular aggregates and total numbers of cells were similar (A, C, E, G). By 120 min, a relatively small number of aggregates containing numerous cells had formed in the cells transfected with wild-type igsf11 (arrowheads in B), though this was not the case in cells of other treatments (D, F, H). (I) Quantitation of the ratio of cellular aggregates to the total number of cells (mean±SE) confirmed that cells were increasingly found in fewer, larger aggregates when transfected with wild-type igsf11. At 120 min, degrees of aggregation differed significantly among treatments overall (F_3,48 = 19.8, P<0.0001). Post hoc means comparisons indicated that aggregation behavior in cells transfected with wild-type igsf11 (B in the figure) differed significantly from that of cells transfected with mutant igsf11 or controls (A in the figure; Tukey Kramer post hoc comparisons, P<0.01); aggregation of cells transfected with mutant forms of igsf11 did not differ significantly from one another or from mock transfected cells. Values shown are least squares means adjusted to control for variation after controlling for minor but significant variation among replicates (P<0.01).