Neutrophils are indispensable for hematopoietic stem cell mobilization induced by interleukin-8 in mice.

摘要: The CXC chemokine interleukin-8 (IL-8/CXCL8) induces rapid mobilization of hematopoietic progenitor cells (HPCs). Previously we showed that could be prevented completely in mice by pretreatment with neutralizing antibodies against the β2-integrin LFA-1 (CD11a). In addition, murine HPCs do not express LFA-1, indicating requires a population accessory cells. Here show polymorphonuclear (PMNs) serve as key regulators IL-8-induced HPC mobilization. role PMNs was studied rendered neutropenic administration single injection antineutrophil antibodies. Absolute neutropenia observed up to 3–5 days rebound neutrophilia at day 7. mobilizing capacity reduced significantly during phase, reappeared recurrence PMNs, and increased proportionally neutrophilic phase. mice, restored infusion purified but mononuclear Circulating metalloproteinase gelatinase B (MMP-9) levels were detectable only animals treated combination IL-8, showing vivo activated are required for restoration However, affected MMP-9-deficient MMP-9 is indispensable These data demonstrate activation circulating PMNs.