Differential expression of cell surface antigens and glial fibrillary acidic protein in human astrocytoma subsets.

We have characterized five distinct cell surface antigens of human astrocytomas and correlated their expression with the expression of glial fibrillary acidic protein (GFAP) and four previously defined cell surface markers of astrocytomas. One of the newly studied antigens, A4, which was originally detected on rat central nervous system (but not peripheral nervous system) neurons, is expressed on GFAP+ human astrocytoma cells, but not on GFAP- astrocytomas or a wide range of other neuroectodermal, epithelial, and hematopoietic cells. Antigens F19 (Mr 140,000/90,000 glycoprotein) and F24 (Mr 90,000 glycoprotein) also show restricted distribution and are expressed on subsets of neuroectodermal and mesenchymal cells.

Extracellular matrix-modulated expression of human cell surface glycoproteins A42 and J143. Intrinsic and extrinsic signals determine antigenic phenotype.

We have used serologic, biochemical, and genetic methods to characterize two stage-specific human differentiation antigens of neural and melanocytic cells: A42 (57,000 Mr glycoprotein) and J143 (140,000/30,000 Mr glycoprotein). The genes determining A42 and J143 cell surface expression in rodent-human hybrids were chromosomally mapped, and the respective human chromosomes were introduced into rodent cells derived from distinct differentiation lineages. Serologic analysis of the resulting hybrid clones has permitted the identification of two types of regulatory signals determining A42 and J143 expression.

Class II histocompatibility antigen expression in human melanocytes transformed by Harvey murine sarcoma virus (Ha-MSV) and Kirsten MSV retroviruses.

Human melanocytes infected with Ki-MSV or Ha-MSV, but not amphotropic MuLV, undergo a series of transformation-related changes that are characteristic of malignant melanoma. These are (a) expression of Ia antigens, in particular DP, DQ, and DR class II histocompatibility gene products, (b) a transformed morphology and ability to grow in soft agar, and (c) a 5-10-fold increase in the cell surface expression of GD3 ganglioside. However, other characteristics of melanoma, such as independence from specific growth factors and loss of adenosine deaminase binding protein were not observed.

Cell surface antigens of human bladder tumors: definition of tumor subsets by monoclonal antibodies and correlation with growth characteristics.

Normal human urothelium and tumors of urothelial origin were analyzed with a panel of seven mouse monoclonal antibodies that identify surface antigens of cultured bladder cancer cell lines. Three categories of antigens were defined on the basis of differential expression on normal urothelium versus bladder tumors. Om5 (a category 1 antigen) is a highly restricted, differentiation antigen detected in the normal urothelium of 50-60% individuals.

Nonhematopoietic cells selected for resistance to tumor necrosis factor produce tumor necrosis factor.

TNF-resistant lines of L cells can be derived from TNF-sensitive populations by repeated exposure to TNF, and these resistant L cells, in contrast to sensitive L cells and other types of cells, lack demonstrable cell surface receptors for TNF. We have now found that TNF-resistant L cells produce a factor that is cytotoxic for L cells and has the following distinguishing characteristics of mouse TNF: it is a protein of 43 kD, composed of 16 kD subunits, that competes with TNF for receptor binding, induces hemorrhagic necrosis of the TNF-sensitive mouse sarcoma Meth A, has synergistic cytotoxic action with interferon, and its activity is neutralized by antibody to TNF. The two conclusions of this study are that cells selected for TNF resistance spontaneously produce a molecule resembling macrophage TNF, and that cells of nonhematopoietic origin are capable of producing TNF.

Immunoanatomic distribution of blood group antigens in the human urinary tract. Influence of secretor status.

Seven mouse monoclonal antibodies and the lectin from Ulex europaeus, detecting blood group specificities of the ABH and Lewis systems, have been used to define the immunoanatomic distribution of these antigenic structures within the human nephron and urothelium. The reagents employed recognize the following blood group related antigens: A (all variants), B, H, Lewisa (Lea), Lewisb (Leb), X (Lewisx), Y (Lewisy) and type 1 precursor chain. We have analyzed the presence of these antigens in histologically normal kidney and urothelium from 22 adults and 3 fetuses by the immunoperoxidase method.

Assignment of human nerve growth factor receptor gene to chromosome 17 and regulation of receptor expression in somatic cell hybrids.

Nerve growth factor (NGF) is a polypeptide hormone which plays a central role in the development and growth of sympathetic and sensory neurons. The effects of NGF on target cells are mediated by a specific cell surface structure, nerve growth factor receptor (NGFr), which has been identified in human cells as a 75,000-mol-wt glycoprotein. We have used a monoclonal antibody to human NGFr to study cell-surface expression of the receptor on a panel of mouse-human neuroblastoma hybrids, and the serological typing results permit assignment of the gene coding for NGFr (NGFR) to chromosome 17q21-qter.

Expression of epidermal growth factor receptor in human cultured cells and tissues: relationship to cell lineage and stage of differentiation.

Mouse monoclonal antibodies have been used to study the distribution of the epidermal growth factor receptor in human cultured cells and tissues. As expected, most epithelial cells expressed epidermal growth factor receptor (EGFr), whereas cells of hematopoietic origin were EGFr-. However, EGFr was found to be differentially expressed on cultured cells of neuroectodermal origin.

A murine monoclonal antibody detecting N-acetyl- and N-glycolyl-GM2: characterization of cell surface reactivity.

Antisera reactive with the ganglioside GM2 were raised by immunizing C57BL/6 mice with the C57BL/6 melanoma JB-RH. Fusion with NS-1 was performed using splenic mononuclear cells from a mouse with high antibody titer. An immunoglobulin M monoclonal antibody (monoclonal antibody 5-3) was identified which was reactive with an antigen that was resistant to heat, trypsin, and Pronase.

Purification, characterization, and antitumor activity of nonrecombinant mouse tumor necrosis factor.

Mouse tumor necrosis factor (TNF) was purified from serum through a series of steps, and each step was monitored for L-cell cytotoxicity in vitro and tumor-necrotizing activity in vivo. The two activities copurified and could not be dissociated. Purified mouse TNF has a specific activity of 2.

Immunohistologic expression of blood-group antigens in normal human gastrointestinal tract and colonic carcinoma.

A panel of 7 mouse monoclonal antibodies and the lectin from Ulex europeus, detecting blood-group-related antigens of the ABH and Lewis systems, have been used to define the distribution of these antigenic structures within the human gastrointestinal tract, and to characterize their expression and modulation in colorectal carcinomas. The reagents employed detect the following blood-group specificities: A (all variants), B, H (type 2), Lewisa, Lewisb, X (Lewisx), Y (Lewisy) and type 1 precursor chain. Immunohistochemical studies demonstrate that these antigens are differentially expressed in various cell types and developmental stages of the human gastrointestinal tract.

Specificity analysis of human monoclonal antibodies reactive with cell surface and intracellular antigens.

Over 4350 human Ig-secreting hybrids have been generated through the fusion of human lymphocytes with NS-1 (mouse), LICR-2, SKO-007, GM4672, or UC729-6 (human) myeloma and lymphoblastoid cell lines. NS-1 proved to be the most satisfactory fusion partner, and 83% of the stable Ig-secreting clones were derived from NS-1 fusions. Three hundred five hybrids produced human monoclonal antibodies (hmAb) reactive with cell surface or intracellular antigens expressed by cultured human tumor cell lines, and 111 of these have undergone detailed serological specificity analysis.

Tumor rejection antigens of chemically induced sarcomas of inbred mice.

Chemically induced sarcomas of inbred mice are immunogenic in syngeneic hosts, and preimmunization with tumor cells leads to resistance to subsequent tumor transplants. The tumor rejection antigens (TRAs) that mediate this reaction are highly specific for each tumor; cross-protection between different syngeneic sarcomas is rare. Isolated membrane and cytosol fractions from two antigenically distinct BALB/c sarcomas, Meth A and CMS5, have TRA activity, and biochemical characterization of the active components from the cytosol and plasma membranes of these two tumors identified a glycoprotein of Mr 96,000.

A molecular mechanism of complement resistance of human melanoma cells.

The susceptibility of human melanoma cells to lysis by human complement after sensitization with the R24 murine IgG3 monoclonal antibody to the GD3 ganglioside antigen was investigated. It was found that the melanoma cell lines were either susceptible (greater than or equal to 70% cytotoxicity) or resistant (less than or equal to 30% cytotoxicity) to complement-mediated killing. We determined the kinetics of binding of C3 to and its subsequent fate on the melanoma cells.

Human melanoma proteoglycan: expression in hybrids controlled by intrinsic and extrinsic signals.

Human malignant melanoma cells express specific chondroitin sulfate proteoglycans (mel-CSPG) on the surface, both in vivo and in vitro. Melanocytes in normal skin show no detectable mel-CSPG but can be induced to express the antigen when cultured in the presence of cholera toxin and the tumor promoter 12-O-tetradecanoylphorbol-13-acetate. Most other cell types do not express mel-CSPG either in vivo or in vitro.

Expression of Lewisa, Lewisb, X, and Y blood group antigens in human colonic tumors and normal tissue and in human tumor-derived cell lines.

Serological and immunopathological analysis of the expression of Lea, Leb, X, and Y blood group antigens on cell lines and tissues was performed using a panel of mouse monoclonal antibodies. The distribution of the antigens was determined on 155 malignant tumor cell lines of various types and 10 short term cultures of normal fibroblasts and kidney cells. Among colon cancers, all four blood group antigens were expressed on the majority of cell lines.

Assignment of the gene for the beta subunit of thyroid-stimulating hormone to the short arm of human chromosome 1.

The chromosomal locations of the genes for the beta subunit of human thyroid-stimulating hormone (TSH) and the glycoprotein hormone alpha subunit have been determined by restriction enzyme analysis of DNA extracted from rodent-human somatic cell hybrids. Human chorionic gonadotropin (CG) alpha-subunit cDNA and a cloned 0.9-kilobase (kb) fragment of the human TSH beta-subunit gene were used as hybridization probes in the analysis of Southern blots of DNA extracted from rodent-human hybrid clones.

Cell surface antigens of murine leukemias induced by radiation leukemia virus. Recognition of individually distinct cell surface antigens by cytotoxic T cells on leukemias expressing crossreactive transplantation antigens.

The specificity of transplantation immunity and T cell cytotoxicity against leukemias induced by RadLV was examined. Subcutaneous inoculation of two RadLV leukemias induced in BALB/c mice, BALBRVB and BALBRVD, resulted in initial tumor growth in CB6F1 mice, followed by complete tumor regression. Mice that had rejected leukemias BALBRVB or BALBRVD were subsequently challenged with various tumors of BALB/c origin.

Cell-surface antigens determined by human chromosomes 1 and 12: comparative serological and somatic cell genetic analysis of eight antigenic systems.

We have previously assigned several genes controlling expression of cell-surface antigens to human chromosomes 1 and 12. In the present study, we characterize three additional cell-surface antigens determined by these chromosomes. Two monoclonal antibodies, AbSR75 and AbMG6, define antigens expressed on a wide range of cultured human cells.

p53 content in relation to cell growth and proliferation in murine L1210 leukemia and normal lymphocytes.

The protein p53 has been reported to be associated with cell transformation and/or proliferation. Using p53 monoclonal antibodies we estimated by flow cytometry the relative content of this protein in individual L1210 leukemic cells from exponentially growing and plateau-phase cultures and compared it with that in normal thymocytes of parental DBA/2 mice and in mitogen-stimulation and nonstimulated human lymphocytes. Simultaneous differential staining of p53 vs DNA and p53 vs RNA, followed by bivariate analysis, made it possible to estimate p53 with respect to cell position in the cell cycle and correlate it with RNA (predominantly rRNA) content.

The serologic response of patients with stage II melanoma to allogeneic melanoma cell vaccines.

Seventeen patients with Stage II malignant melanoma were treated with vaccines prepared from three allogeneic melanoma cell lines in an attempt to induce a humoral immune response against melanoma cell surface antigens. The patients were free of detectable melanoma at the time of vaccination. Vaccines were prepared from three melanoma cell lines that expressed highly restricted melanocyte differentiation antigens.

Three mouse monoclonal antibodies to human differentiation antigens: reactivity with two mucin-like antigens and with connective tissue fibers.

Three human differentiation antigens (MU78, MT334, and MQ49) have been defined by mouse monoclonal antibodies developed from mice immunized with ovarian carcinoma cell lines. Their distribution was determined on 148 cultured cell lines of various histologic types and on frozen sections of 16 normal tissues. MU78 was found in fibrillar structures in soft connective tissue with a distribution resembling that of elastin fibers; however, elastin fibers in elastic cartilage and in the aorta were nonreactive.

Role of human chromosome 11 in determining surface antigenic phenotype of normal and malignant cells. Somatic cell genetic analysis of eight antigens, including putative human Thy-1.

The expression of eight serologically and biochemically distinct human cell surface antigens defined by monoclonal antibodies was examined on a panel of rodent-human somatic cell hybrids. Cosegregation was observed for human chromosome 11, and surface expression of all eight antigens was studied. Serological analysis of hybrids containing defined segments of human chromosome 11 permitted the regional assignment of genes controlling antigens JF23 (90 kD glycoprotein), G344 (25 kD), T43 (85 kD), A124, and NP13 to chromosome 11pter-q13, and of genes controlling Q14 (130 kD), MC139 (35 kD), and K117 (25 kD) to chromosome 11q13-qter.