Phenotypic and functional comparison of monocytes from cord blood and granulocyte colony-stimulating factor-mobilized apheresis products

Objective. It is well established that T cells are effector cells in graft- vs-host disease (GVHD), yet the contribution of graft monocytes, is less we ll characterized. Therefore, monocytes in cord blood (CB) and granulocyte c olony-stimulating factor-mobilized apheresis products (G-AP), two stem cell grafts associated with reduction of acute and chronic GVHD and relative re duction of acute GVHD, respectively, were compared phenotypically and funct ionally. Materials and Methods. The frequencies, phenotypes, and pinocytosis activit ies of monocytes from CB and G-AP were determined by flow cytometry and the ir allostimulatory potential in a primary mixed leukocyte reaction. Results. G-AP contained significantly more monocytes than CB (24.9% +/- 7.1 % vs 8.8% +/- 1.5% CD14(+) and 62.4 +/- 27.5 x 10(6) vs 0.9 +/- 0.2 x 10(6) CD14(+) cells/mL). Monocytes from both sources revealed similar phenotypes . They expressed CD4, CD11a, CD11b, CD11c, CD18, CD32, CD33, CD45R0, CD48, CD50, CD54, CD58, CD64, CD86, CD102, CD116, CD123, and HLA-DR; showed no ex pression of CD1a and CD83; and weak expression of CD16, CD45RA, and CD80. T he levels of CD80 and CD86 expression were comparable; however, in contrast to G-AP monocytes, CB monocytes lacked CD40. There was no difference in pi nocytosis activity and allostimulatory capacity of CB and G-AP monocytes. Conclusions. Monocytes in CB and G-AP are phenotypically and functionally c omparable. The only difference observed is the lack of CD40 on CB monocytes . (C) 2001 International Society for Experimental Hematology. Published by Elsevier Science Inc.