title: Monoclonal Lym-1 antibody-dependent lysis of B-lymphoblastoid tumor targets by human complement and cytokinine-exposed mononuclear and neutrophilic polymorphonuclear leukocytes.
abstract: Lym-1 is a murine IgG2a monoclonal antibody that recognizes a polymorphic variant of HLA-DR antigens on malignant B cells, with minimal cross-reactivity with normal tissues. Because it can be safely administered in vivo, a detailed knowledge of its ability to recruit and trigger the antitumor immune effector systems is required to optimize potential serotherapeutic approaches in B-lymphoma patients. By using Raji cells as a model of B-lymphoma targets, we found that Lym-1 activates complement-mediated lysis efficiently. Moreover, Lym-1 was capable of triggering the antibody-dependent cellular cytolysis (ADCC) by peripheral blood mononuclear cells (MNCs). On the contrary, it failed to trigger neutrophilic polymorphonuclear leukocyte (PMN)-mediated ADCC activity. In an attempt to enhance Lym-1 ADCC by MNCs and PMNs, nine biologic response modifiers were tested. MNC-mediated Lym-1 ADCC was significantly stimulated by interleukin-2 (IL-2) and unaffected by other mediators, including gamma-interferon (gamma-IFN), tumor necrosis factor a (TNFalpha), and granulocyte-macrophage colony-stimulating factor (GM-CSF). On the other hand, PMN-mediated Lym-1 ADCC was induced or significantly augmented by various cytokines, such as GM-CSF, TNFalpha, and gamma-IFN, and chemotaxins, such as formyl peptides (FMLP), complement fragment C5a, and IL-8. Both MNC- and PMN-mediated ADCC was unaffected by granulocyte colony-stimulating factor (G- CSF) and insulin-like growth factor-1 (IGF-1). Finally, only GM-CSF and TNFalpha augmented the number of PMNs actually engaged in the binding of Raji target cells. The findings presented here, in particular those showing stimulatory activity of biologic response modifiers, may inspire new attempts for developing Lym-1 antibody-based approaches to the therapy of B lymphomas.
authors.affiliation: First Medical Clinic, Department of Internal Medicine, University of Genova, Genova, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Ottonello
authors.forename: P
authors.initials: P
authors.lastname: Morone
authors.forename: P
authors.initials: P
authors.lastname: Dapino
authors.forename: F
authors.initials: F
authors.lastname: Dallegri
mesh_terms: D000328:Adult; D000911:Antibodies, Monoclonal / Q000276:immunology / Q000494:pharmacology*; D000912:Antibodies, Neoplasm / Q000276:immunology / Q000494:pharmacology*; D000918:Antibody Specificity; D000920:Antibody-Dependent Cell Cytotoxicity / Q000187:drug effects; D002051:Burkitt Lymphoma / Q000276:immunology / Q000473:pathology*; D002630:Chemotactic Factors / Q000494:pharmacology; D003165:Complement System Proteins / Q000276:immunology*; D016207:Cytokines / Q000494:pharmacology; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology; D006133:Growth Substances / Q000494:pharmacology; D006684:HLA-DR Antigens / Q000276:immunology*; D006801:Humans; D007155:Immunologic Factors / Q000494:pharmacology*; D007376:Interleukin-2 / Q000494:pharmacology*; D007963:Leukocytes, Mononuclear / Q000276:immunology*; D014411:Neoplastic Stem Cells; D009504:Neutrophils / Q000187:drug effects / Q000276:immunology*; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
chemical_list: D000911:Antibodies, Monoclonal; D000912:Antibodies, Neoplasm; D002630:Chemotactic Factors; D016207:Cytokines; D006133:Growth Substances; D006684:HLA-DR Antigens; D007155:Immunologic Factors; D007376:Interleukin-2; D014409:Tumor Necrosis Factor-alpha; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D003165:Complement System Proteins