The analysis revealed no statistically significant differences in the proliferation of GFP+ stromal cells and consistently with this, we observed that despite the increase in spleen cellularity due to leukemia infiltration, the number of GFP+ stromal cells per field diminished instead of increasing, further suggesting that CXCL13 expansion likely results from induction rather than from an increase in stromal cell proliferation. This evidence concerns the gene CXCL13 and leukemia.