Fig. 3.
Chemokine receptor expression and chemotaxis of lymphoid progenitors. (A) From left to right: BM pro-B cells, CLP-2, CLP-1, and early thymic immigrants (double-negative 1 c-kit+hCD25+) were sorted and analyzed by semiquantitative RT-PCR for the expression of multiple CCRs. cDNA quantities were normalized according to GADPH or actin expression over three subsequent 5× dilutions. (B and C) lin− BM cells from pTα-hCD25 mice were added to inserts that were placed in wells containing medium alone or the following chemokines: CCL5, CCL2, CCL19, CCL21, CXCL12, or CCL25. Responding cells were harvested 2 h later, stained for hCD25, B220, and c-kit, and analyzed by flow cytometry. (B) Migration as percentage of the input. (C) Chemotactic index. (n = 3 experiments.)