Human plasmacytoma with an unusual karyotype growing in vitro and producing light-chain immunoglobulin

A new human plasmacytoma line (Karpas 707) was established from the cells of the bone-marrow and peripheral blood of a patient with Bence-Jones-positive multiple myeloma. The cells of this line resembled the patient's malignant cells and fresh myeloma cells from nine other patients in being Epstein-Barr viral nuclear antigen negative. They looked like plasma cells and they secreted only lambda light chains. Both these cells and the patient's fresh cells were hypodiploid and contained the Philadelphia chromosome and several other markers. This line seems to be the first human plasmacytoma line since the IgE lambda-producing line (U266) established in 1968, and it may be suitable for the production of human monoclonal antibodies.

The differential ultrastructural localization of immunoglobulin heavy and light chains in human haematopoietic cell lines

The ultrastructural localization of immunoglobulin heavy and light chains has been investigated in nine haematopoietic cell lines, using a technique which involves the treatment of lightly prefixed cells with saponin to allow penetration of the antibody-peroxidase conjugate. The synthesis and secretion of immunoglobulin was also studied in these cell lines. Immunoglobulin was found to be localized in the cisternae and on the membranes of the rough endoplasmic reticulum, perinuclear space and/or Golgi apparatus. In each case staining for heavy chains was weak or absent in the perinuclear space while staining for light chains was usually strong. Additionally in three cell lines immunoperoxidase staining indicated that heavy chains were absent from the Golgi apparatus despite the observed presence of light chains in the Golgi apparatus and the secretion of combined immunoglobulin into the supernatant. The results obtained suggest compartmentalization of the synthesis of light and heavy chains and indicate that the technique of immunoelectron microscopy may significantly contribute to an understanding of the mechanisms involved in immunoglobulin synthesis, intracellular transport and secretion.

In vitro radiosensitivity of human leukemia cell lines

The in vitro radiobiologic survival values (n, D0) of four tumor lines derived from human hematopoietic tumors were studied. These cell lines were HL50 (n = 1.3, D0 = 117 rad[1.17 Gy]), promyelocytic leukemia; K562 (n = 1.4, D0 = 165 rad[1.65 Gy]), erythroleukemia; 45 (n = 1.1, D0 = 147 rad[1.47 Gy]), acute lymphocyte leukemia; and 176 (n = 4.0, D0 = 76 rad[0.76 Gy]), acute monomyelogenous leukemia. More cell lines must be examined before the exact relationship between in vitro radiosensitivity and clinical radiocurability is firmly established.

Purification and physicochemical characterization of a human cytotoxic factor produced by a human haemic cell line

A cytotoxic factor, produced by a human lymphoblastoid cell line [Karpas (1977) Br. J. Cancer 35, 152--160; Karpas (1977) Br. J. Cancer 36, 437--445], was purified both from the cell extracts and from the culture medium containing the cell lysate, by using ammonium sulphate precipitation, DEAE-cellulose chromatography, gel filtration and affinity chromatography on concanavalin A--Sepharose and on [3H]amino-ethanol--glass beads. Two factors, Factor I and Factor II, were separated by DEAE-cellulose chromatography. Factor I was eluted from this column at 30 mM-aminoethanol/HCl buffer, pH 8.0, whereas Factor II was bound strongly to DEAE-cellulose and was eluted only at 325 mM-aminoethanol/HCl buffer, pH 8.0. The purified Factor I migrated as a single band on polyacrylamide-gel electrophoresis. Its isoelectric point, pI, was 8.0 +/- 0.3. Its sedimentation coefficient, S20,w, was 3.5 +/- 0.1 S and its apparent molecular weight, Mr, was 65 000 +/- 1000 as determined by sedimentation-velocity and sedimentation-equilibrium measurements. A linear relationship between molecular weight and concentration was found in equilibrium runs, suggesting a non-spherical shape of the molecule. Factor I is not a glycoprotein, inasmuch as it does not bind to concanavalin A--Sepharose. It consists of two subunits (Mr 32 000 +/- 4000), migrating on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis as a single band. Factor II had pI 6.0 +/- 0.4 and Mr 75 000 +/- 3000. Factors I and II are thus different proteins.

Characteristics of a cell line established from a child with familial acute myeloid leukaemia

The properties of an unusual new cell line from a child with acute myeloid leukaemia (AML) is described. The patient, his mother and grandmother all died within 2 years of AML. Karyotypic analysis suggests that the cells which grow in vitro represent a proliferation of the child's leukaemic cells. The presence of myeloid alkaline phosphatase in these cells suggests that they represent a proliferation of malignant myeloblasts. During the first year in culture a significant percentage of the cells formed E-rosettes, but the cells failed to react with monoclonal anti-T-cell antibodies. The cells are SmIg, Fc, C3 and EBNA negative. Ultrastructural examination of the cells revealed cytoplasmic inclusion bodies which contained virus-like particles. These inclusion bodies and particles were similar to those observed by us in two other human leukaemic cell lines and not unlike those in fresh human leukaemic cells, as reported by others.

Sinus histiocytosis with massive lymphadenopathy: virological, immunological and morphological studies

The histiocytes from a patient with sinus histiocytosis were tested for the presence of Epstein-Barr viral nuclear antigen (EBNA) before and after in vitro growth. On both occasions the histiocytes as well as the lymphocytes were EBNA negative. Likewise the profile of EBV viral capsid antibody (VCA) suggests that this virus is unlikely to be directly involved in the development of the disease. The maintenance of an unusually high level of antibodies to EBV and measles, both viruses which produce persistent infections, indicates that the humoral immune response is active. That a normal humoral response occurred in response to mumps virus during the same period suggests that a deficiency in the cell mediated immune response to the persistent viruses might be the reason for the abnormally high antibody levels. The fresh as well as the cultured histiocytes had only Fc receptors. The affected lymph node lymphocytes developed unusual large inclusion bodies following in vitro culture.

Dissociation of opsonized particle phagocytosis and respiratory burst activity in an Epstein-Barr virus-infected myeloid cell line

A continuous tissue culture cell line (Karpas line 120), derived from a patient with acute myeloblastic leukemia, not only demonstrates myeloblastic morphology and in vitro expression of several myeloid-specific biochemical markers but also contains Epstein-Barr virus (EBV) nuclear antigen. The present studies demonstrate EBV-genome-specific DNA within the total cellular DNA by molecular hybridization, thus establishing the presence of stable viral genome integration. The cells demonstrate complex coordinated myeloid functions including ingestion, degranulation, and respiratory burst activity. Line 120 cells show a respiratory burst (superoxide and hydrogen peroxide generation and hexosemonophosphate shunt activity) in response to soluble (phorbol myristate acetate) and particulate (latex beads) stimuli, as do normal granulocytes. They ingest complement-opsonized particles (lipopolysaccharide-oil droplets, zymosan, and bacteria), and degranulate in response to them. However, unlike normal granulocytes, the line 120 cells do not demonstrate respiratory burst activity in response to these complementopsonized particles. The dissociation between ingestion of complement-opsonized particles and activation of oxygen-dependent bactericidal activity severely impairs bacterial killing as compared with normal polymorphonuclear phagocytes.

Phenotypic characterization of a virus producing line established from a patient with leukaemia/lymphoma: comparison with T-lymphoblastic and myeloblastic lines

The properties have been studied of a haemic cell line established from a patient with longstanding non-Hodgkin's lymphoma after transformation to acute leukaemia. The cells are EBNA, Fc, C3 and SmIg and Ia-like antigen negative. The continuous in vitro proliferation and karyotype abnormalities suggest malignancy. The cells contain only the lymphoid type of alkaline phosphatase and a high level of terminal deoxynucleotidyl transferase and as they formed E-rosettes during the first year in culture they may be of T-cell lineage. Since the patients' leukaemic cells have not been studied it is impossible to know whether the cultured cells represent an in vitro proliferation of the patient's malignant cells or an outgrowth of a subpopulation of cells. In the cytoplasm of many cells inclusion bodies containing virus-like particles, similar to those observed in fresh human leukaemia cells, were often seen. As this new virus is biologically active, infection of the cells by virus may explain their continuous proliferation in vitro.

Transformation of normal bone-marrow cells by a leukaemic cell line associated with a presumptive new human virus

Intracytoplasmic leukovirus-like bodies were found in the cells and culture medium of a T-cell lymphoblast line established from a leukaemic patient. When the cells were lethally irradiated and added to normal bone-marrow cells the latter were transformed into continuous replication and produced the same types of virus-like particle.

Alkaline phosphatase in Epstein-Barr viral nuclear antigen--positive cell lines

The production and nature of alkaline phosphatase were studied in Epstein-Barr viral nuclear antigen-positive, surface membrane immunoglobulin negative-cell lines established from two patients, one with acute myeloid leukemia and one with acute lymphoblastic leukemia. The acute myeloid leukemia-derived cells contained myeloid alkaline phosphatase, while the acute lymphoblastic leukemia-derived cells contained lymphoid alkaline phosphatase. The presence of the myeloid-specific enzyme in a surface membrane immunoglobin--negative cell line suggests that the line is composed of myeloid precursor cells and that such cells may be susceptible to infection with Epstein-Barr virus.

Constitutive and inducible granulocyte-macrophage functions in mouse, rat, and human myeloid leukemia-derived continuous tissue culture lines

Fourteen continuous tissue culture cell lines derived from mouse, rat, or human granulocyte-macrophage cancers were studied for expression of spontaneous and inducible markers of differentiated cells. Five cell lines (two mouse, two rat, and one human) synthesized myeloperoxidase spontaneously, and a fifth mouse line showed biochemically inducible enzyme. Twelve lines (6 mouse, 3 rat, and 3 human) produced lysozyme (muramidase), and all had detectable beta-glucuronidase. Superoxide generation was detected in one mouse, and three human cell lines following stimulation with phorbol myristate acetate. Maturation to differentiated polymorphonuclear leukocyte or macrophage morphology was induced in 3 cell lines (2 mouse and 1 human) following culture in diffusion chambers in total-body-irradiated rats. In vitro morphological differentiation was inducible in one (mouse) cell line exposed to casein, thioglycolate, or plasma from irradiated rats or mice. These findings indicate that mammalian cell lines derived from granulocyte-macrophage cancers stably express several combinations of differentiation markers. The patterns of expression of these markers did not always correlate with the morphological stage of differentiation.

A humoral cytotoxic substance produced by a human killer cell line

The production of a cytotoxic factor synthesized by human haemic killer cells growing in vitro is described. The factor can be found extra- and intra-cellularly. It is released from the cells by an apocrine form of secretion, illustrated by light and electron micrographs. The culture fluid from 14C-labelled killer cells reveals numerous radioactive bands following SDS-gel electrophoresis. The killing factor is precipitated by 30 to 60% saturation of ammonium sulphate. Cultures of human rhabdomyosarcoma and osteosarcoma cells are more susceptible to the killer cells than normal human dermal or lung fibroblasts. During contact or killer with target cells a higher level of cytotoxic activity can be detected in the culture fluid. The cell-killing activity is completely inactivated by 30 min at 60 degrees C, but it is not absorbed by target cells during 1 h of incubation. The cytotoxic factor is unlikely to be an interferon since it did not prevent the replication of a wide range of viruses and only a low level of interferon could be detected in the culture medium. The introduction of Strep. faecalis into cultures of killer cells caused their transformation into immunoblast-like cells, indicating their lymphoid origin. The cells did not phagocytose the microorganism. When the humoral factor was injected into fibro-sarcoma-bearing mice approximately 50% survived, whereas all control animals died.

Leucocyte alkaline phosphatase elevation in human acute leukaemia derived cell lines cultured in diffusion chambers

Leucocyte alkaline phosphatase (LAP) was histochemically detected in 7 to 18% of cells in tissue culture lines derived from the peripheral blood or bone marrow of each of 5 patients with untreated acute myelogenous or monomyelogenous leukaemia and in 30% of the cells in a clonal line of a rat promyelocytic leukaemia. Following transfer to diffusion chambers intraperitoneally implanted into total body irradiated rats, LAP levels were detected in up to 92% of human and 80% of rat leucocytes. There was no associated morphologic differentiation. In rat leukaemia cells peroxidase and myeloid specific esterase also increased from tissue culture levels. Return of cells to tissue culture decreased enzymes to pre-implant levels. Addition of plasma or peritoneal fluid from irradiated rats to cells in tissue culture again induced LAP. In contrast, LAP was not increased under these conditions with cell lines derived from patients with acute lymphatic leukaemia, or Sezary cell leukaemia. These studies indicate that a humoral factor in peritoneal fluid and plasma of irradiated rats increases LAP in human as well as rat leucocytes.

Null-cell properties of a lymphoid cell line from a child with acute lymphoblastic leukaemia

Cultured cells established from the bone marrow of a child with null-cell acute lymphoblastic leukaemia (ALL) have been studied. After 8 months in vitro, the cytological, cytochemical and immunological properties of the cultured cells were very similar to those of the patient's cells. Many of the cultured cells had morphological and cytogenetic abnormalities often found in acute leukaemia. The cells were EBNA-negative. This unique culture of ALL-derived null cells might provide information as to the aetiology and origin of malignant cells.

Immunoglobulin expression and synthesis by human haemic cell lines

Twenty-six human cell lines derived from a variety of lymphoid and non-lymphoid malignancies, were investigated for their immunological markers, with special reference to the class of immunoglobulin expressed. Twenty-five of the lines stained positively for surface immunoglobulin and IgD together with IgM proved to be the major immunoglobulin classes on these cells. Six of the lines were chosen for a study of their immunoglobulin synthesis patterns over an 18-h period and the immunoglobulin produced was analysed on SDS-polyacrylamide gel electrophoresis. Patterns obtained from the cell lines were similar to that from normal lymph node lymphocytes and differed markedly to plasma cells. Two of the cell lines had abnormal immunoglobulin synthesis patterns characterized as free light chains in one case. The cell lines are evaluated for their usefulness as models of immunoglobulin synthesis and analogues of normal and neoplastic states.

A human haemic cell line capable of cellular and humoral killing of normal and malignant cells

A line of human leukaemia-derived cells is described that kills a wide range of human and animal cell lines, whether normal or malignant, even at a ratio of 1:1. During exposure to the target cells, the killer cells released a factor into the culture medium which destroyed target cells in the absence of the killer cells. This phenomenon occurs without exogenous complement and requires no pre-treatment of target or killer cells. The humoral factor is a protein precipitable by 60% saturation of ammonium sulphate and has a mol. wt. of approximately 70,000; It prevented the growth of a fibrosarcoma in mice.