title: Proliferation and cytogenetic analysis of hairy cell leukemia upon stimulation via the CD40 antigen.
abstract: Using the CD40 system, in vitro proliferation of hairy cell leukemia (HCL) was examined in 43 patients. In this culture system, cells were stimulated by interleukin-4 (IL-4) and anti-CD40 monoclonal antibodies (MoAbs) that were added in soluble form or were cross-linked via their Fc part using Fc gamma RII-transfected mouse fibroblast cells. Proliferation was induced and confirmed by 3H-thymidine incorporation in 14 cases and by the presence of metaphases in 42 cases. 3H-thymidine incorporation showed a heterogeneous pattern: cross-linking of anti-CD40 gave the highest proliferation in 8 cases; in 11 cases, stimulation with anti-CD40 MoAbs alone, without cross-linking also resulted in proliferation; the addition of IL-4 further enhanced 3H-thymidine incorporation in 5 cases, but suppressed this phenomenon in 5 other cases. The CD40 system proved to be very effective in obtaining cytogenetic data. With a success rate of 42 of 43 patients tested, we found clonal abnormalities in 8 cases (19%) and nonclonal abnormalities with involvement of one or two abnormal metaphases in another 7 cases. The chromosomes most frequently involved in the abnormal karyotypes, both structurally and numerically, were chromosomes 5, 7, and 14. By fluorescence-activated cell-sorting analysis of the cultured cells, and by immunophenotypic analysis of metaphase spreads, T-cell growth could be excluded and the HCL-lineage confirmed. Stimulation via the CD40 antigen is an excellent tool for growing hairy cell leukemia cells.
authors.affiliation: Department of Hematology, University Medical Center, Leiden, The Netherlands.
authors.forename: H C
authors.initials: HC
authors.lastname: Kluin-Nelemans
authors.forename: G C
authors.initials: GC
authors.lastname: Beverstock
authors.forename: P
authors.initials: P
authors.lastname: Mollevanger
authors.forename: H W
authors.initials: HW
authors.lastname: Wessels
authors.forename: E
authors.initials: E
authors.lastname: Hoogendoorn
authors.forename: R
authors.initials: R
authors.lastname: Willemze
authors.forename: J H
authors.initials: JH
authors.lastname: Falkenburg
mesh_terms: D000328:Adult; D000368:Aged; D015703:Antigens, CD / Q000502:physiology*; D000944:Antigens, Differentiation, B-Lymphocyte / Q000502:physiology*; D019013:CD40 Antigens; D002455:Cell Division; D002478:Cells, Cultured; D003582:Cytogenetics; D005260:Female; D006801:Humans; D016130:Immunophenotyping; D015847:Interleukin-4 / Q000494:pharmacology; D007943:Leukemia, Hairy Cell / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D017452:Receptors, IgG / Q000502:physiology
chemical_list: D015703:Antigens, CD; D000944:Antigens, Differentiation, B-Lymphocyte; D019013:CD40 Antigens; D017452:Receptors, IgG; D015847:Interleukin-4