Good and poor mobilizing patients differ in mobilized CD34+cell adhesion molecule profiles

BACKGROUND: Alterations in expression of adhesion molecules are important in the trafficking of hematopoietic progenitors and probably in the mobilization process. Relatively little and conflicting data are currently available on the differences in expression between good and poor mobilizing patients. STUDY DESIGN AND METHODS: In this study, the expression of eight adhesion molecules on the collected CD34+ cells from 36 patients undergoing mobilization was determined. RESULTS: Good mobilizing patients, defined as those who collected their target in one apheresis procedure, had significantly fewer cells that expressed CD11a (LFA-1) and CD54 (ICAM-1) and borderline fewer that expressed CD11c, CD49d (VLA-4), and CD49d (VLA-5). No differences were detected in CD11b (Mac-1), CD15s (sLe(x)), or CD62L (L-selectin). Linear regression analysis identified number of prior chemotherapy courses and expression of CD11 a (LFA-1) as independent predictive factors for mobilization efficiency. Good and poor mobilizing patients had approximately the same number of total CD34+ cells collected and little difference in times to engraftment. CONCLUSIONS: CD11a (LFA-1) expression inversely correlates with mobilization efficiency. Elucidation of the mechanism(s) underlying these observations will require further study.