Cytokine mobilization of stem cells from bone marrow to the circulation is inhibited by concurrent administration of plasma from poorly mobilizing patients (Stem Cells 16:139, 1998). Chemokines as well as cytokines may be involved in stem cell mobilization. Differences in mobilization kinetics induced by chemokines compared to cytokines exist. An experiment was designed to inject a cantharidin (chemokine), the active ingredient of Chinese blister beetle extract (CBBE) intraperitoneally (ip) into adult female Blab/c mice (0.5ml per mouse). The mice were necropsied 15 minutes post injection and blood, marrow and spleen cells were assayed for colony forming unit-granulocyte-monocyte/macrophage (CFC-GM), high proliferative potential colony forming cells (HPP) and CD34/45+ cells. Granulocyte colony stimulating factor ( 15 mg/kg) and erythropoietin (500 u/kg) (G-CSF/EPO) were injected ip as a cytokine control. The number of CD34/45+ cells, CFC-GM and HPP-CFC in the spleen decreased 15 minutes after ip injection of CBBE while after ip injection of G-CSF/EPO those cell numbers had increased. Neither CBBE nor G-CSF/EPO induced migration of hematopoietic stem cells into the peritoneal cavity 15 minutes post ip injection. Unlike subcutaneous injection, local reactions did not occur after ip injection. Potentially, intermediary cells responsible for initiating local reactions are present in subcutaneous tissues but not the peritoneal cavity. Chemokine mediated rapid mobilization was reported previously for some cytokines (Blood 85:2269, 1995). Whether this phenomenon is a consequence of chemokine secreted by an intermediary cell is unclear. The number of platelets increased significantly 15 min post ip injection of CBBE but was unchanged after injection of G-CSF/EPO. This indicated that Cantharidin might be involved in the release of platelets. The relative roles of chemokines and cytokines in migration of stem cells needs clarification and may be influenced by intermediary cells that are not uniformly distributed at all anatomic sites.
|Original language||English (US)|
|Issue number||11 PART II|
|State||Published - 2000|
ASJC Scopus subject areas
- Cell Biology