title: Developmental hierarchy during early human B-cell ontogeny after autologous bone marrow transplantation using autografts depleted of CD19+ B-cell precursors by an anti-CD19 pan-B-cell immunotoxin containing pokeweed antiviral protein.
abstract: Sequential immunophenotypes of bone marrow (BM) and peripheral blood (PBL) lymphoid cells from 15 B-lineage acute lymphoblastic leukemia (ALL) patients who underwent autologous bone marrow transplantation (BMT) during complete remission were determined by dual-color immunofluorescence and multiparameter flow cytometry. Autografts were depleted of CD19+ B-cell precursors by an immunochemopurging protocol that combines B43-PAP, a potent anti-CD19 immunotoxin, and the cyclophosphamide congener 4-hydroperoxycyclophosphamide (4-HC). A marked interpatient variation was observed in the appearance and expansion of B-cell precursors repopulating the posttransplant marrow. The expression of CD10 and CD19 antigens during early B-cell ontogeny post-BMT preceded the expression of CD20, CD21, CD22, CD40, and sIgM. The surface antigen profiles of the emerging B-cell precursors were similar to those of fetal liver or fetal bone marrow B-cell precursors. Our comparisons of BM and PBL samples from patients in the early post-BMT period demonstrated that (1) PBL initially contains fewer B-lineage cells than does BM, and (2) circulating B-lineage lymphoid cells have a more mature immunophenotype than do BM B-lineage lymphoid cells. Comparison of the surface antigen profiles of day 30 versus day 100 or year 1 BM or PBL lymphoid cells showed an increase in the percentages of CD10+CD22- undifferentiated lymphocyte precursors, as well as CD19+sIgM- B-cell precursors (pre-pre-B), consistent with a time-dependent expansion of these B-cell precursor populations post-BMT. Importantly, the percentages of CD10+CD22+ and CD19+sIgM+ B-cell precursor (pre-B) populations also increased between 30 days and 1 year post-BMT, confirming the ability of emerging immature B-cell precursors to differentiate along the B-precursor pathway. The acquisition and expression of B-lineage differentiation antigens at different stages of the post-BMT B-cell ontogeny support the notion that the expression of these antigens is developmentally programmed. Similar to patients in previous autologous BMT studies, recipients of B-cell precursor-depleted autografts had normal or nearly normal serum immunoglobulin levels, suggesting that the maturing B-cell/plasma cell populations can produce and secrete immunoglobulins. The development of a functional CD19+ B-lineage lymphoid compartment in recipients of autografts which were depleted of CD19+ B-cell precursors corroborates the previously postulated existence of CD19- B-lineage lymphoid progenitor cells.
authors.affiliation: Department of Therapeutic Radiology-Radiation Oncology, University of Minnesota Health Sciences Center, Minneapolis.
authors.forename: F M
authors.initials: FM
authors.lastname: Uckun
authors.forename: S
authors.initials: S
authors.lastname: Haissig
authors.forename: J A
authors.initials: JA
authors.lastname: Ledbetter
authors.forename: P
authors.initials: P
authors.lastname: Fidler
authors.forename: D E
authors.initials: DE
authors.lastname: Myers
authors.forename: V
authors.initials: V
authors.lastname: Kuebelbeck
authors.forename: D
authors.initials: D
authors.lastname: Weisdorf
authors.forename: K
authors.initials: K
authors.lastname: Gajl-Peczalska
authors.forename: J H
authors.initials: JH
authors.lastname: Kersey
authors.forename: N K
authors.initials: NK
authors.lastname: Ramsay
mesh_terms: D015703:Antigens, CD / Q000032:analysis* / Q000276:immunology; D018941:Antigens, CD19; D000944:Antigens, Differentiation, B-Lymphocyte / Q000032:analysis* / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology* / Q000473:pathology; D001853:Bone Marrow / Q000196:embryology; D001854:Bone Marrow Cells; D016465:Bone Marrow Purging / Q000379:methods*; D016026:Bone Marrow Transplantation; D003520:Cyclophosphamide / Q000031:analogs & derivatives; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D006412:Hematopoietic Stem Cells / Q000276:immunology* / Q000473:pathology; D006801:Humans; D007136:Immunoglobulins / Q000097:blood; D016130:Immunophenotyping; D000922:Immunotoxins; D008099:Liver / Q000166:cytology / Q000196:embryology; D009699:N-Glycosyl Hydrolases; D010940:Plant Proteins; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000601:surgery*; D054789:Ribosome Inactivating Proteins, Type 1; D014182:Transplantation, Autologous
chemical_list: D015703:Antigens, CD; D018941:Antigens, CD19; D000944:Antigens, Differentiation, B-Lymphocyte; D007136:Immunoglobulins; D000922:Immunotoxins; D010940:Plant Proteins; D054789:Ribosome Inactivating Proteins, Type 1; D003520:Cyclophosphamide; D009699:N-Glycosyl Hydrolases; C024275:pokeweed antiviral protein; C011272:perfosfamide