Comparisons between the miRNA profiles of each fraction. (A) Pearson correlation coefficients for the comparisons between all fractions. (B) A 3-dimensional representation of the PCA. The cell fractions were grouped and depicted as follows: FrA cells (red), early B cells (FrB/C, C′, D, and E; blue), transitional B cells (T1 and T2/3; orange), mature B cells (Fo, recFo, and Mz; green), and B1 lineage B cells (black). The colored ellipsoids represent the 95% confidence boundaries for each of the groups described. The results described in this figure are in agreement with the model for development of the B2 B-cell lineage.