title: Anti-histone H1 IgGs possess proliferative activity towards human T-leukaemia CEM cells.
abstract: The aim of this study was to characterize the proliferative activity of the anti-histone H1 IgGs towards human T-leukaemia CEM cells.
  
  
  METHODS
  Anti-histone H1 IgGs were purified from blood serum of systemic lupus erythematosus patients by precipitation of serum proteins with 50% ammonium sulfate followed by a sequential affinity chromatography on Protein G-Sepharose and histone H1-Sepharose columns. To avoid contamination with other proteins, anti-histone H1 IgGs were subjected to strongly acidic pH 2.0 during gel filtration through HPLC column. The effects of the anti-histone H1 IgGs on cell viability and cell cycle were tested by MTS-assay and flow cytometry, correspondingly. The cross-reactivity of the anti-histone H1 antibodies towards heterogenetic and cellular antigens was evaluated by Western-blot analysis.
  
  
  RESULTS
  It was found that incubation of CEM cells with the HPLC-purified anti-histone H1 IgGs resulted in significant stimulation of cell growth by 46% after 48 h of incubation. These IgGs possess an antigenic poly-specificity to positively charged heterogenetic antigens and different cellular antigens. FITC-labeled and biotinylated anti-histone H1 IgGs are internalized by CEM cells and preferentially accumulated in the cytoplasm.
  
  
  CONCLUSIONS
  The anti-histone H1 IgGs are shown to internalize human T-leukemia CEM and stimulate their proliferation. These IgGs are polyspecific toward cellular antigens.
authors.affiliation: Institute of Cell Biology, National Academy of Sciences of Ukraine, Lviv 79005, Ukraine.
authors.forename: Y
authors.initials: Y
authors.lastname: Kit
authors.affiliation: Institute of Cell Biology, National Academy of Sciences of Ukraine, Lviv 79005, Ukraine.
authors.forename: I
authors.initials: I
authors.lastname: Magorivska
authors.affiliation: Danylo Halytsky Lviv National Medical University, Lviv 79010, Ukraine.
authors.forename: R
authors.initials: R
authors.lastname: Bilyi
authors.affiliation: Institute of Cell Biology, National Academy of Sciences of Ukraine, Lviv 79005, Ukraine.
authors.forename: S
authors.initials: S
authors.lastname: Myronovskij
authors.affiliation: Institute of Cell Biology, National Academy of Sciences of Ukraine, Lviv 79005, Ukraine.
authors.forename: R
authors.initials: R
authors.lastname: Stoika
mesh_terms: D000888:Antibodies, Anti-Idiotypic / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology*; D000915:Antibody Affinity / Q000276:immunology; D000918:Antibody Specificity / Q000276:immunology; D015153:Blotting, Western; D002453:Cell Cycle / Q000187:drug effects*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects; D002846:Chromatography, Affinity; D002850:Chromatography, Gel; D003429:Cross Reactions / Q000276:immunology; D003593:Cytoplasm / Q000378:metabolism; D006657:Histones / Q000276:immunology*; D006801:Humans; D015458:Leukemia, T-Cell / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D008180:Lupus Erythematosus, Systemic / Q000097:blood / Q000276:immunology
chemical_list: D000888:Antibodies, Anti-Idiotypic; D006657:Histones; C048844:anti-IgG