Which of the following surface glycoprotein is most often expressed in human hematopoietic stem cells
Ref Robbins 9/e p590 CD34 derives its name from the cluster of differentiation protocol that identifies cell surface antigens. CD34 was first described on hematopoietic stem cells independently by Civin et al. and Tindle et al. as a cell surface glycoprotein and functions as a cell-cell adhesion factor. It may also mediate the attachment of hematopoietic stem cellsto bone marrow extracellular matrix or directly to stromal cells. The CD34 protein is a member of a family of single-pass transmembrane sialomucin proteins that show expression on early hematopoietic and vascular-associated tissue. However, little is known about its exact function. CD34 is also an impoant adhesion molecule and is required for T cells to enter lymph nodes. It is expressed on lymph node endothelia, whereas the L-selectin to which it binds is on the T cell.Conversely, under other circumstances CD34 has been shown to act as molecular "Teflon" and block mast cell, eosinophil and dendritic cell precursor adhesion, and to facilitate opening of vascular lumina.Finally, recent data suggest CD34 may also play a more selective role in chemokine-dependent migration of eosinophils and dendritic cell precursors.Regardless of its mode of action, under all circumstances CD34, and its relatives podocalyxin and endoglycan, facilitates cell migration.
CD22
CD40
CD15
CD34
Haematology