title: The monoclonal antibody 97A6 defines a novel surface antigen expressed on human basophils and their multipotent and unipotent progenitors.
abstract: Basophils (Ba) and mast cells (MC) are important effector cells of inflammatory reactions. Both cell types derive from CD34(+) hematopoietic progenitors. However, little is known about the cell subsets that become committed to and give rise to Ba and/or MC. We have generated a monoclonal antibody (MoAb), 97A6, that specifically detects human Ba, MC (lung, skin), and their CD34(+) progenitors. Other mature hematopoietic cells (neutrophils, eosinophils, monocytes, lymphocytes, platelets) did not react with MoAb 97A6, and sorting of 97A6(+) peripheral blood (PB) and bone marrow (BM) cells resulted in an almost pure population (>98%) of Ba. Approximately 1% of CD34(+) BM and PB cells was found to be 97A6(+). Culture of sorted CD34(+)97A6(+) BM cells in semisolid medium containing phytohemagglutinin-stimulated leukocyte supernatant for 16 days (multilineage assay) resulted in the formation of pure Ba colonies (10 of 40), Ba-eosinophil colonies (7 of 40), Ba-macrophage colonies (3 of 40), and multilineage Ba-eosinophil-macrophage and/or neutrophil colonies (12 of 40). In contrast, no Ba could be cultured from CD34(+)97A6(-) cells. Liquid culture of CD34(+) PB cells in the presence of 100 ng/mL interleukin (IL)-3 (Ba progenitor assay) resulted in an increase of 97A6(+) cells, starting from 1% of day-0 cells to almost 70% (basophils) after day 7. Culture of sorted BM CD34(+)97A6(+) cells in the presence of 100 ng/mL stem cell factor (SCF) for 35 days (mast cell progenitor assay) resulted in the growth of MC (>30% on day 35). Anti-IgE-induced IgE receptor cross-linking on Ba for 15 minutes resulted in a 4-fold to 5-fold upregulation of 97A6 antigen expression. These data show that the 97A6-reactive antigen plays a role in basophil activation and is expressed on multipotent CD34(+) progenitors, MC progenitors, Ba progenitors, as well as on mature Ba and tissue MC. The lineage-specificity of MoAb 97A6 suggests that this novel marker may be a useful tool to isolate and analyze Ba/MC and their progenitors.
authors.affiliation: Department of Medicine, Division of Hematology, University of Tübingen, Tübingen, Germany. hjbuehri@med.uni-tuebingen.de
authors.forename: H J
authors.initials: HJ
authors.lastname: Bühring
authors.forename: P J
authors.initials: PJ
authors.lastname: Simmons
authors.forename: M
authors.initials: M
authors.lastname: Pudney
authors.forename: R
authors.initials: R
authors.lastname: Müller
authors.forename: D
authors.initials: D
authors.lastname: Jarrossay
authors.forename: A
authors.initials: A
authors.lastname: van Agthoven
authors.forename: M
authors.initials: M
authors.lastname: Willheim
authors.forename: W
authors.initials: W
authors.lastname: Brugger
authors.forename: P
authors.initials: P
authors.lastname: Valent
authors.forename: L
authors.initials: L
authors.lastname: Kanz
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D000918:Antibody Specificity; D015703:Antigens, CD / Q000032:analysis / Q000235:genetics; D018952:Antigens, CD34 / Q000032:analysis / Q000235:genetics; D001491:Basophils / Q000166:cytology* / Q000187:drug effects / Q000502:physiology; D001854:Bone Marrow Cells / Q000166:cytology* / Q000473:pathology; D002460:Cell Line; D002478:Cells, Cultured; D003114:Colony-Forming Units Assay; D016207:Cytokines / Q000494:pharmacology; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000187:drug effects / Q000502:physiology; D006636:Histamine Release; D006801:Humans; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000473:pathology; D008168:Lung / Q000166:cytology; D051379:Mice; D008807:Mice, Inbred BALB C; D011994:Recombinant Proteins / Q000494:pharmacology; D012867:Skin / Q000166:cytology
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D018952:Antigens, CD34; D016207:Cytokines; D011994:Recombinant Proteins