Adhesion receptor expression by CD34+ cells from peripheral blood or bone marrow grafts: correlation with time to engraftment.

Objective: This study was undertaken to define the pattern of cell adhesion receptor expression by the CD34+ progenitor cells from mobilized peripheral blood and bone marrow from normal and autologous donors, and to correlate the adhesion receptor profile with time to blood cell recovery for patients undergoing autologous transplant.

Methods: Blood cell recovery was determined by absolute neutrophil count (> 500/microL), time to last red cell transfusion, and platelet count (> 50,000/microL and > 100,000/microL). The analysis for expression of adhesion receptors alphaL (CD11a), alpha2 (CD49b), alpha3 (CD49c), alpha4 (CD49d), alpha5 (CD49e), alpha6 (CD49f), beta1 (CD29), L-selectin (CD62L), ICAM-1 (CD54), PECAM-1 (CD31), HCAM (CD44), and P-selectin (CD62P) was performed by two-color flow cytometry.

A specific heptapeptide from a phage display peptide library homes to bone marrow and binds to primitive hematopoietic stem cells.

Phage display peptide libraries have enabled the discovery of peptides that selectively target specific organs. Selection of organ-specific peptides is mediated through binding of peptides displayed on phage coat protein to adhesion molecules expressed within targeted organs. Hematopoietic stem cells selectively home to bone marrow, and certain adhesion receptors critical to this function have been demonstrated.