Chemokine and cytokine production and response in CD34⁺ progenitors and mobilized peripheral blood stem cells

Several methods for CD34⁺ cell selection have been utilized to obtain early progenitor cells for in vitro cell studies and in vivo transplantation purposes. CD34⁺ progenitors were isolated using the Ceprate avidin-biotin immunoadsorption column (Cellpro) and the MiniMACS magnetic bead separation system (Miltenyi) CD34' progenitors have been found to have an increase internal calcium response when exposed to the chemokines RANTES, MCP- , MIP-1ct and IP-10. This was demonstrated using confocal microscopy with lndo-1 staining for calcium. CD34⁺ progenitors were also shown to increase migration through an human umbilical vein endothelial cell layer when attracted to the chemokines RANTES, interteukin-8, MCP- , MIP-1a, IP-10 and SDF-1[S Also serum ELISA levels were looked at in patients undergoing cytokine mobilization of perpherial blood stem cells. Serum ELISA levels were completed for cytokine and chemokine release of interleukin-1 a, interteukin-1, interleukin-6, interleukin-7, interleukin-8, TNF-a, RANTES, MCP-1 and MIP-1a. These serum levels were compared with laboratory results for white cell count, absolute neutrophil count, mononuclear cell count and platelet count over the course of mobilization. In general, patients showed a release of chemokines and cytokines into the serum with the exception of interleukin-1 a. The chemokine levels of interleukin-8 and MCP-1 were in the higher than normal range. The activation status of CD34⁺ thus appears to be modulated and affected by chemokines.