Interestingly, CD34+DNAM-1− cells from HD PBMC did not express CXCR4 (Fig. 8a), thus suggesting that under normal conditions Lin−CD34+DNAM-1brightCXCR4+ precursors are barely detectable in PB, and may be released from BM in case of need such as during chronic inflammation. Here, CXCR4 is linked to Huntington disease.