title: T cell depletion of human bone marrow. Comparison of Campath-1 plus complement, anti-T cell ricin A chain immunotoxin, and soybean agglutinin alone or in combination with sheep erythrocytes or immunomagnetic beads.
abstract: The aim of this study was to compare the extent of in vitro T cell depletion and recovery of hematopoietic progenitor cells achieved with five methods of T cell depletion. Bone marrow samples from the same source were treated with monoclonal antibody Campath-1 (CP1) and human complement, XomaZyme-H65 (anti-T cell ricin A chain immunotoxin), or soybean agglutinin (SBA) alone or in combination with sheep erythrocytes (EAET) or a cocktail of immunomagnetic beads (B) directly coated with anti-CD2, anti-CD3, or anti-CD8 monoclonal antibodies. Residual T cells were enumerated by limiting dilution analysis, EAET rosetting, and proliferative responses to phytohemagglutinin. The results of this study demonstrated the following reductions in BM T cells as detected by limiting dilution analysis (mean % control): SBA+B (99.9%), SBA+EAET (99.8%), CP1+C' (99.4%), anti-T cell ricin A chain immunotoxin (99.0%), and SBA alone (94.2%). Neither PHA response nor enumeration of residual EAET rosettes provided discriminating differences in the degree of T cell depletion by treatment method when T cell reductions exceeded 99.0% by LDA. These results demonstrate the ability of CP1+C', XomaZyme-H65, and SBA plus sheep erythrocyte or magnetic bead depletion to achieve a greater than 99% reduction of BM T cells and the importance of limiting dilution analysis in defining differences in T cell numbers when depletion exceeded 99%.
authors.affiliation: Human Immunogenetics Laboratory, Memorial Sloan-Kettering Cancer Center, New York, New York 10021.
authors.forename: J N
authors.initials: JN
authors.lastname: Frame
authors.forename: N H
authors.initials: NH
authors.lastname: Collins
authors.forename: T
authors.initials: T
authors.lastname: Cartagena
authors.forename: H
authors.initials: H
authors.lastname: Waldmann
authors.forename: R J
authors.initials: RJ
authors.lastname: O'Reilly
authors.forename: B
authors.initials: B
authors.lastname: Dupont
authors.forename: N A
authors.initials: NA
authors.lastname: Kernan
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D016026:Bone Marrow Transplantation; D003114:Colony-Forming Units Assay; D003165:Complement System Proteins; D004338:Drug Combinations; D004912:Erythrocytes; D006412:Hematopoietic Stem Cells / Q000276:immunology; D006801:Humans; D000922:Immunotoxins; D037102:Lectins; D007958:Leukocyte Count; D007963:Leukocytes, Mononuclear / Q000276:immunology; D008213:Lymphocyte Activation; D008212:Lymphocyte Depletion / Q000379:methods; D008863:Microspheres; D037121:Plant Lectins; D051381:Rats; D012397:Rosette Formation; D012756:Sheep; D030262:Soybean Proteins; D013025:Glycine max; D013601:T-Lymphocytes / Q000276:immunology; D010835:Phytohemagglutinins
chemical_list: D000911:Antibodies, Monoclonal; D003165:Complement System Proteins; D004338:Drug Combinations; D000922:Immunotoxins; D037102:Lectins; D037121:Plant Lectins; D030262:Soybean Proteins; C028824:soybean lectin; D010835:Phytohemagglutinins