title: Lectin binding sites on CD34+ human haematopoietic stem cells and lymphocytes from peripheral blood: an ultrastructural post-embedding study.
abstract: This study was performed to obtain a better insight into the glycosylation pattern of human CD34+ haematopoietic stem cells and lymphocytes from peripheral blood using an ultrastructural post-embedding technique. Lectins applied were derived from Canavalia ensiformis (Con A), Triticum vulgare (WGA), Lycopersicon esculentum (LEA), Limulus polyphemus (LPA), Ulex europaeus-I (UEA-I), Bauhinia purpurea (BPA), Glycine max (SBA), Helix pomatia (HPA), Arachis hypogaea (PNA) and Erythrina cristagalli (ECA). Our results showed almost identical staining patterns with both CD34+ cells and mature lymphocytes from peripheral blood. Con A displayed a prominent reactivity with the nuclear envelope and a weak staining of the plasma membrane. As demonstrated by an elaborate lectin double-labelling technique, WGA revealed an opposite staining pattern. Following neuraminidase treatment of sections, BPA, PNA and SBA exhibited a prominent staining of the plasma membrane in CD34+ cells and lymphocytes as well. Membrane reactivity with HPA was restricted to the majority of lymphocytes, presumably T-lymphocytes. Infrequently occurring dense cytoplasmic (lysosomal) bodies were reactive with a variety of lectins, and a weak diffuse nuclear labelling was observable with LPA, UEA-I, WGA and Con A. It is tempting to speculate that carbohydrate moieties on plasma membranes may be involved in the complex mechanisms characterizing cell-to-cell interactions (adhesion) and particularly in the so-called phenomenon of homing.
authors.affiliation: Institute of Pathology, University of Cologne, Germany.
authors.forename: T A
authors.initials: TA
authors.lastname: Kuemmel
authors.forename: J
authors.initials: J
authors.lastname: Thiele
authors.forename: A H
authors.initials: AH
authors.lastname: Blaeser
authors.forename: C
authors.initials: C
authors.lastname: Wickenhauser
authors.forename: S E
authors.initials: SE
authors.lastname: Baldus
authors.forename: R
authors.initials: R
authors.lastname: Fischer
mesh_terms: D000818:Animals; D018952:Antigens, CD34 / Q000276:immunology / Q000378:metabolism*; D001665:Binding Sites; D002448:Cell Adhesion; D002462:Cell Membrane / Q000378:metabolism; D004076:Digoxigenin / Q000032:analysis; D006412:Hematopoietic Stem Cells / Q000276:immunology / Q000378:metabolism* / Q000648:ultrastructure; D006801:Humans; D007150:Immunohistochemistry; D037102:Lectins / Q000378:metabolism*; D009685:Nuclear Envelope / Q000378:metabolism; D051381:Rats; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: D018952:Antigens, CD34; D037102:Lectins; D004076:Digoxigenin