Which of the following surface glycoproteins is most often expressed in human hematopoietic stem cell

Ans. is 'd' i.e., CD 34 o Lymphocytes and other leukocytes have a number of surface antigens or marker --> leukocyte differentiation antigen. o A paicular leucocyte differentiation antigen has been given a CD (cluster of differentiation) number on the bases of its reaction with a cluster of monoclonal antibodies. o These markers reflect the stage of differentiation and functional propeies of cell. Primary T cell Associated -> CD 1, CD3, CD4, CD5, CD8 Primary B cell associated --> CD 10, CD 19, CD20, CD21, CD23, CD79a Primary monocyte or macrophage associated --> CD1 1 c, CD 13, CD 14, CD 15, CD33, CD64 Primary NK cell associated --> CD16, CD56 Primary stem cell and progenitor cell associated 3 CD34 Activation markers -3 CD30 Present on all leukocytes -3 CD45