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C J Wikstrand

Publications and source records attributed to C J Wikstrand.

At least 73 records · Page 4Linked to original sources
PubMed1986

Specific chromosomal abnormalities characterize four established cell lines derived from malignant human gliomas.

The four permanent human glioma-derived cell lines reported here are the first such lines for which the karyotypes have been followed from the original biopsies through the establishment of the lines in culture. Although ploidy changes were seen, each line retained either distinctive marker chromosomes or the overall original chromosomal distribution allowing the origin of each line to be established with certainty. D-263 MG expresses glial fibrillary acidic protein, all lines except D-245 MG are tumorigenic in athymic mice, and each line displays a unique pattern with respect to in vitro growth parameters and expression of biochemically defined markers, oncofetal antigens and lymphoid-associated markers. D-245 MG and D-259 MG are able to grow in the absence of supplemental glutamine; glutamine synthetase was detected in these cell lines both by immunocytochemistry and by direct assay. Thus, the four permanent human glioma-derived cell lines described here are representative of glioma lines in their general characteristics. D-259 MG retains numerous double minute chromosomes (DMs), D-263 MG contains two marker chromosomes with breaks in 9p, and D-247 MG and D-245 MG with stemlines containing 96 and 89 chromosomes contain eight and six normal copies (respectively) of chromosome No. 7. The retention in these four cell lines of the most common chromosomal abnormalities seen in biopsies of malignant human gliomas provides the opportunity to investigate the meaning of these specific chromosomal changes.

Animals↗
PubMed1986

Glioma-associated antigens defined by monoclonal antibodies against an avian sarcoma virus-induced rat astrocytoma.

S69-c15 is a highly immunogenic cell line derived from an avian sarcoma virus (ASV)-induced astrocytoma in F-344 rats. Monoclonal antibody (Mab) production was attempted by fusing F-344 rat splenocytes and mouse P3 X 63/Ag8.653 myeloma cells after a syngeneic immunization protocol. 336 fusion clones were screened by cell surface radioimmunoassay (CS-RIA) against the immunizing line S69-c15, rat kidney fibroblast line S203-c11 and Walker rat carcinoma line. Mabs 7G4, 9F1, 10E3 and 10E7 which reacted only with S69-c15 were chosen. Further analysis demonstrated that these Mabs reacted only with rat (13/23 astrocytomas, 2/4 gliomas, 1/11 neurinomas) or mouse (2/10 astrocytomas) neurogenic tumor cells induced by both viral and chemical agents. Reciprocal competition assays suggested that 7G4, 9F1 and 10E3 recognized the same epitope and that 10E7 reacted with a spatially close determinant. Antigen activity could not be found in adult rat tissues (brain, heart, lung, liver, kidney, spleen, thymus, intestine, muscle and peripheral nerve) and fetal brain (8, 12, 20 days gestation) by either absorption analysis or tissue staining. Preliminary characterization indicated that the epitope may be polypeptide-associated. Further antigen purification and tumor localization can be attempted with these Mabs.

Animals↗
PubMed1986

Production and characterization of two human glioma xenograft-localizing monoclonal antibodies.

Multiple fusions following immunization of athymic mice with the extensively characterized human glioma cell line D-54 MG resulted in the selection of several antibodies (Mabs) highly reactive with tumors of neuroectodermal origin and unreactive with normal nervous system tissue. Two Mabs, C12 and D12, which localized specifically to tumors in athymic mouse-human glioma xenograft paired label localization assays, are IgG3 antibodies; both bind readily to staphylococcal protein A in column purification and radioimmunoprecipitation procedures. Both iodinate via the chloramine-T method yielding 125I-immunoreactive product by direct cell surface radioimmunoassay and absorption assay. By indirect cell surface radioimmunoassay, a cultured cell line panel consisting of 17 gliomas, 3 medulloblastomas, 2 neuroblastomas, 2 melanomas, and 2 fetal and 2 adult brain-derived cell lines was examined; the two Mabs were highly similar but distinct in their reactivity profiles. Each was positive with greater than 47% of the gliomas tested (C12, 9 of 17; D12, 8 of 17); and with 1 of 3 medulloblastomas, 1 of 2 melanomas, and cell lines derived from 12- and 16-week-gestation human fetal brain. No reactivity was observed with neuroblastoma or adult brain-derived cell lines or with neutral glycolipids and gangliosides extracted from D-54 MG xenografts or human glioma cell lines. Notable extraneuroectodermal reactivity included that of Mab D12 for splenic trabeculae and the spermatids and Sertoli cells in the testes. Following immunoprecipitation of [3H]leucine labeled cell membrane preparations, Mabs C12 and D12 have consistently yielded unique bands in the Mr 180,000 and Mr 88,000 regions respectively. When used in paired label localization experiments in s.c. D-54 MG xenograft-bearing athymic mice, Mabs C12 and D12 demonstrate similar localization patterns, attaining peak localization indices at day 3 (D12) or 4 (C12); the maximum percentage of injected Mab bound to tumor ranged from 5% (D12) to 8% (C12). The peak tumor/normal brain localization ratios (167-181) attained by these Mabs at days 1-2 followed by their rapid clearance suggest that these Mabs are potentially useful imaging and therapeutic agents for further investigation.

Animals↗
PubMed1986

Specific imaging of human brain tumor xenografts utilizing radiolabelled monoclonal antibodies (MAbs).

At the present time, specific imaging and treatment of central nervous system malignancies is not possible. The development of monoclonal hybridoma technology may provide the solution to this problem. We have utilized human glioma-derived cell lines (HGCL) transplanted subcutaneously and intracranially into athymic mice and rats to evaluate the imaging and localizing properties of a panel of MAbs. MAbs 81C6, C12, and D12 and 81C6 Fab have shown significant in vivo localization against HGCL D-54 MG and 81C6 against U-251 MG when compared to equivalent non-specific MAbs. In subcutaneous D-54 MG-induced xenografts, maximal localization indices (LI) of up to 15.0 for 81C6, 6.8 for 81C6 Fab, 6.48 for C12, and 4.47 for D12 have been seen. The tumor-tissue ratios for normal brain have ranged from 235 for 81C6 to 167 for D12. The total percent injected dose for 81C6 was nearly 5% in U-251 MG tumors and 10% of the initial dose in D-54 tumors, while the percent injected dose for control MAb were 1.9% and 2.8%, respectively. Four subcutaneously growing U-251 MG tumors were clearly imaged using 131I-81C6. With intracranially growing D-54 MG, 131I-81C6 provided external imaging of intracranial tumors at sizes as small as 20 mg while 131I-45.6, a non-specific MAb, provided imaging only when tumors achieved sizes greater than 300 mg. These data indicate that operationally specific MAbs and MAb Fab can specifically localize and be used to image human tumors transplanted into immunocompromised animals. The animal models described in this paper provide a sensitive method of evaluating MAbs in pre-human trials.

Animals↗
PubMed1985

Monoclonal antibodies reactive with epitopes restricted to glial fibrillary acidic proteins of several species.

The highly reproducible histochemical localization of glial fibrillary acidic protein (GFAP)+ qualifies it as an important marker of astrocytes in both research and clinical applications. The primary objective of this study was to produce monoclonal antibodies having the advantage of invariant specificity, affinity, and titer to GFAP-specific epitopes of wide species distribution. We report here the characterization of four monoclonal antibodies that recognize the same or spatially close epitopes specific to GFAP. The epitope(s) detected has been phylogenetically conserved; human, bovine, ovine, canine, porcine, rabbit, guinea pig, rat, murine, and chicken brain homogenates all specifically absorb monoclonal antibody activity. Of importance to the routine application of these new anti-GFAP monoclonal antibodies is the demonstration here of the stability of the antigen-antibody interaction in normal, reactive, and neoplastic astrocytes of both rat and human origin following various methods of fixation.

Animals↗
PubMed1985

Antigenic heterogeneity of human anaplastic gliomas and glioma-derived cell lines defined by monoclonal antibodies.

The antigenic heterogeneity of human neuroectodermal tumors defined by both murine and human monoclonal antibodies (MAs) is reported; no patterns of reactivity defining degree of anaplasia, in vitro morphology, or immunogen used were apparent. We investigated the reactivity of 20 distinct murine MAs defining markers of glioma-associated or predominantly lymphoid distribution for 13 human glioma-derived (HGL) cell lines and frozen sections of 19 human glioblastoma multiforme (GBM) and six astrocytomas (AST). Methods included radioimmunoassay, immunofluorescence, immunohistochemistry, and absorption analysis. Two markers, HLA-A,B and human Thy-1, exhibited no deviation; all HGL cell lines tested bound high levels of specific MA. Individual HGL cell line reactivity with the MA panel ranged from 30 to 70%. HGL cell lines (7/13) which reacted with greater than or equal to 50% of the antiglioma MAs had the highest (30-70%) positive reactivity rates with the anti-lymphoid marker MA panel; complex antigenicity in one system correlated with multiple antigens in the other. Within the anti-lymphoid marker MA panel, subpopulations of 4/13 HGL cell lines were clearly positive for the HLA-DR (Ia) antigens; another 3/13 HGL cell lines were strongly positive for common acute lymphocytic leukemia antigen (CALLA). With the exception of Thymocyte 1 antigen (Thy-1), reactivity for early and mature T-cell markers was infrequent and sporadic. Lymphoid marker expression by HGL cell lines is highly heterogeneous, ranging from few (Thy-1 and HLA-A,B) to complex expression of Ia, T-cell, and lymphoid tumor markers. GBM and AST tissues were antigenically less complex; for each of 6/8 anti-glioma MA, 70-100% of GBM and 66-100% of AST were positive. Two MAs were highly reactive (7/10, 8/9) with GBM sections and minimally so (1/6) with AST. Antigenic expression in gliomas is complex and heterogeneous; however, clear differences in lymphoid marker expression, the identification of widely and rarely expressed glioma-associated antigens, and the potential of immunologic differentiation between GBM and AST by large panels of MAs will serve to reduce the complexity and may be of potential diagnostic or prognostic significance.

Animals↗
PubMed1985

Establishment and characterization of the human medulloblastoma cell line and transplantable xenograft D283 Med.

A new continuous cell line and transplantable xenograft, D283 Med, was derived from the peritoneal implant and ascitic fluid of a child with metastatic medulloblastoma and grew in vitro in suspension culture with spontaneous macroscopic spheroid formation. The in vitro population doubling time was 52.55 hours. Mean colony forming efficiency in an agarose medium was 1.83 +/- 0.56%. The cell line, D283 Med, grew in athymic mice as serially transplantable intracranial and subcutaneous xenografts. Intracranial tumors grew as masses of small cells with scant cytoplasm and abundant mitotic figures and prominent anuclear zones resembling neuroblastic rosettes. Subcutaneous (SQ) tumors were markedly cellular neoplasms but did not contain rosettes. They expressed glutamine synthetase, neuron-specific enolase and neurofilament protein. Glial fibrillary acidic protein and S-100 protein were not detected. The SQ tumors grew to 500 mm3 with a latency of 52.55 +/- 12.5 days and a doubling time of 9.33 +/- 2.39 days. The stemline karyotypes of the peritoneal implant and ascitic fluid cells contained an extra copy of chromosome number 11 and three marker chromosomes (8q+, 17p+, 20q+). The cultured cell line and subcutaneous and intracranial xenografts retained the three marker chromosomes and differed from the original karyotype only in that they lacked the additional copy of chromosome number 11. This cell line and transplantable xenograft may allow further analysis of the biological properties and therapeutic sensitivity of human medulloblastoma.

Animals↗
PubMed1984

Characterization of three restricted specificity monoclonal antibodies raised against the human glioma cell line D-54 MG.

Monoclonal antibodies ( MCAs ) have been derived from a fusion of P3-NS1/1-Ag 4-1 (NS1) myeloma cells and splenocytes immunized to human glioma cell line D-54 MG. MCAs 2F3 , 4C7 , and 5B7 were analyzed by cell surface radioimmunoassay (CS-RIA), quantitative absorption, indirect immunofluorescence, and peroxidase-anti-peroxidase (PAP) immunohistology of unfixed tissue samples. MCA 2F3 exhibits the most highly restricted pattern of reactivity we have observed, reacting only with 5/12 glioblastoma cell lines and 1/4 fetal skin lines by CS-RIA, and to 9/11 glioblastoma tissue samples by PAP and absorption analysis; this MCA is totally nonreactive with melanomas, neuroblastomas, meningiomas, and control non-central nervous system tumors, and to adult and fetal tissues including brain, thymus, spleen, liver, lung, heart, gut, skin, and muscle by PAP analysis. MCAs 4C7 and 5B7 demonstrate neuroectodermal tumor cross-reactivity profiles, reacting with either melanomas ( 5B7 ) or melanomas and neuroblastomas ( 4C7 ); both are reactive with fetal skin, brain, and thymus of less than or equal to 16 weeks of gestational age. Other than this latter fetal antigen reactivity, these MCAs share the same negative reactivity profile described above for MCA 2F3 . Data from experiments using control or 0.02% EDTA-treated confluent cell monolayers of D-54 MG as antibody absorbents showed that the antigens detected are present in the extracellular matrix material remaining following cell removal. The data presented here establish that these highly restrictive anti-human glioma cell line MCAs are expressed in primary human gliomas; that the markers defined are developmental in nature, in that they are expressed by human fetal tissue, but not by adult tissue; and that in conjunction with previously characterized specificities, these markers of antigenic heterogeneity will be valuable in model system studies of therapeutic response heterogeneity.

Absorption↗
PubMed1983

Immunobiology of primary intracranial tumors. Part 8: Serological responses to active immunization of patients with anaplastic gliomas.

Serial serological studies were carried out on 19 of 20 patients with malignant gliomas who were actively immunized with one of two human glioma tissue culture cell lines (D-54MG or U-251MG). Most patients mounted a significant serum reaction to histocompatibility antigens (HLA's), as well as an antibody response to fetal bovine serum (FBS) which was added to the glioma-cell inoculum. These two sources of antibody accounted for greater than 90% of the antibody induced by these inoculations. Two patients continued to have significant amounts of binding antibody to the original immunizing cell line following exhaustive absorptions of FBS and these two had all remaining significant antibody removed by further absorption of the serum against the 2-T osteogenic sarcoma tissue culture cell line known to possess antigens cross-reactive with human gliomas. One single patient continued to show significant antibody binding to the original glioma cell line following absorption against FBS, human platelets, and the 2-T cell line, and therefore seems to have produced glioma-distinctive antibodies in response to immunization. The antibody preparation from this patient was also cytotoxic against the original glioma cell line, as well as another recently cultured human glioblastoma cell line. The significance of these serological studies is discussed as it relates to immunological responses patients with gliomas may make to active immunization.

Antibodies, Anti-Idiotypic↗
PubMed1983

Demonstration of complex antigenic heterogeneity in a human glioma cell line and eight derived clones by specific monoclonal antibodies.

We have investigated the antigenic heterogeneity of human glioma cells and its correlation with other parameters of tumor cell heterogeneity (karyotype, 2':3' cyclic nucleotide 3'-phosphohydrolase expression, in vitro morphology) using the established human glioma cell line D-54 MG and eight single-cell-derived clones. The panel of antibodies used included 3 previously described heterologous sera raised against human gliomas and lamb oligodendroglia and 10 monoclonal antibodies with demonstrated reactivity for tumors of neuroectodermal origin, human fetal tissue, or human Thy-1. Antigen expression was determined by cell surface radioimmunoassay and peroxidase-antiperoxidase immunohistology. The use of a monoclonal antibody panel composed of ten reagents of varied specificity resulted in the demonstration of highly variable and complex antigenic patterns on the cell surfaces of cloned subpopulations of the human glioma cell line D-54 MG. Only one antigen, human Thy-1, was present on the parent line and all clones; the remaining nine antigens exhibited a distribution unrelated to other predictive parameters of genotypic or phenotypic heterogeneity such as karyotype, 2':3' cyclic nucleotide 3'-phosphohydrolase expression, or in vitro morphology. With the exception of clones 3 and 4, which shared a common antigen profile but exhibited distinctly different in vitro morphological patterns, the detected antigenic profile of each clone was distinct, with the proportion of expressed antigens ranging from 2 of 10 (clone 2) to 10 of 10 (clone 1). The demonstration of distinct, selectively maintained cell subpopulations within a human glioma cell line has direct implications for immunotherapeutic designs.

2',3'-Cyclic Nucleotide 3'-Phosphodiesterase↗
PubMed1983

Human glioma-mesenchymal extracellular matrix antigen defined by monoclonal antibody.

The distribution and localization of a glioma-associated antigen defined by monoclonal antibody 81C6 has been examined using human cultured cell lines and tissues. Monoclonal antibody 81C6 was selected from a hybridoma fusion of spleen cells of mice immunized with the glial fibrillary acidic protein-positive human glioma cell line U-251 MG. Results of cell surface radioimmunoassay and absorption analysis demonstrated that 81C6 defined a glioma-mesenchymal extracellular matrix (GMEM) antigen expressed by 14 of 16 gliomas, 1 of 3 neuroblastomas, 1 of 7 melanomas, 2 of 6 sarcoma cell lines, and 8 of 9 cultured fibroblast lines. GMEM was not expressed by carcinoma or by the myeloid-lymphoid cell lines examined. Within the central nervous system, GMEM was expressed in 10 of 11 glioblastomas but was undetected in 5 of 6 astrocytomas and in normal adult and fetal brain by peroxidase-antiperoxidase immunohistology. In glioblastomas, the GMEM antigen was localized to basement membranes of the distinctive glomeruloid endothelial proliferations and hyperplastic blood vessels. The GMEM antigen was also expressed in 3 of 3 glioblastoma cell lines and 6 of 8 glioblastoma biopsy xenografts in athymic nude mice. Among non-central nervous system tissues and tumors, GMEM was found by peroxidase-antiperoxidase immunohistology in normal liver sinusoids, spleen red pulp sinusoids, kidney medullary tubule interstitium, and glomerular mesangium and in association with vascular and stromal elements of several undifferentiated tumors. The GMEM antigen is distinct from previously described forms of fibronectin, laminin, collagen types I to V, hyaluronic acid, chondroitin sulfate, and heparin, as determined by absorption analysis and immunohistological localization in tissues. The expression of GMEM in glioblastoma but not normal brain, association with glioblastoma-proliferative endothelium basement membranes, and expression in glioblastoma cell lines and nude mouse xenografts suggest that GMEM may be a useful marker of gliomas in vivo and in vitro.

Animals↗
PubMed1982

Human fetal brain antigen expression common to tumors of neuroectodermal tissue origin.

The antigenic relationship between human tumors of neuroectodermal origin and fetal brain were further investigated by characterization of two hybridoma antibodies derived from a fusion of P3-NS1/1-Ag 4-1 (NSI) myeloma cells and splenocytes hyperimmunized to second trimester human fetal brain homogenate. Monoclonal antibodies (MAs) 1H8cl 2 and 1H8cl 3 were analyzed by cell surface radioimmunoassay (CS-RIA), quantitative absorption, indirect immunofluorescence, and peroxidase-antiperoxidase (PAP) immunohistology. MA 1H8cl 3 is the more broadly reactive, binding to 9/14 glioblastoma (GBM), 2/3 neuroblastoma, 1/2 melanoma, and 1 medulloblastoma cell line(s) by CS-RIA analysis, and to 12/15 GBM, fetal brain, spleen, and liver, and adult spleen by PAP analysis. MA 1H8cl 2 is more restricted, binding to 7/14 GBM, 2/3 neuroblastoma, 1 medulloblastoma, and 2/3 fetal skin fibroblast cell line(s) by CS-RIA, and to 9/15 GBM and fetal brain and spleen by PAP analysis. Control non-central nervous system tumors and normal adult tissue including brain, thymus, lymph node, liver, kidney, lung, skin, and pancreas, were unreactive with both 1H8cl 2 and 1H8cl 3 by CS-RIA, PAP, and absorption analysis. The data presented here establish the unique nature of the detected antigenic specificities as compared to previously described oncofetal and onconeural antigens, and define two immune reagents which are operationally specific for tumors of neuroectodermal origin within the adult central nervous system.

Antibodies, Monoclonal↗
PubMed1982

Expression of human fetal brain antigens by human tumors of neuroectodermal origin as defined by monoclonal antibodies.

The antigenic relationships between human tumors of neuroectodermal origin and fetal brain were investigated by the production of hybridoma antibodies derived from a fusion of P3-NS1/1-Ag 4-1 (NS1) myeloma cells with splenocytes from a mouse multiply immunized with an homogenate of second-trimester human fetal brain tissue. Two monoclonal antibodies (MAs), 4D2cl 6 and 7H10cl 4, were studied in detail by cell surface radioimmunoassay (CS-RIA), quantitative absorption, indirect immunofluorescence, and peroxidase-anti-peroxidase (PAP) immunohistology. MA 4D2cl 6 binds to 5 of 14 glioblastoma (GBM) cell lines, 1 of 2 melanoma cell lines, 1 of 3 neuroblastoma cell lines, and 1 of 5 fetal fibroblast lines by CS-RIA and to 13 of 13 GBM, 1 neuroblastoma, and fetal brain, liver, spleen, and adult spleen unfixed frozen tissue by PAP analysis. MA 7H10cl 4 binds to 13 of 14 GBM, 1 of 3 neuroblastoma, and 1 medulloblastoma cell line(s) by CS-RIA analysis and to 13 of 13 GBM, 1 neuroblastoma, fetal brain, liver, spleen, thymus, and adult spleen by PAP analysis. Control non-central nervous system tumors and normal adult tissue, including brain, were unreactive with both MAs by CS-RIA, PAP, and absorption analysis. Tissue distribution and localization analyses established that MAs 4D2cl 6 and 7H10cl 4 recognize specificities of shared fetal-neuroectodermal-lymphoid distribution which are operationally specific within the adult central nervous system and which are not related to previously described oncofetal or onconeural antigens.

Antibodies, Monoclonal↗
PubMed1981

Hyperimmunization of non-human primates with BCG-CW and cultured human glioma-derived cells. Production of reactive antisera and absence of EAE induction.

The efficacy and non-toxicity of BCG-cell wall preparation (BCG-CW) + cultured human glioma-derived cells as immunogen in non-human primates (Macaca fascicularis) were investigated to determine the optimal conditions for immunization without induction of experimental allergic encephalomyelitis (EAE). BCG-CW vaccines were prepared with non-irradiated and irradiated (10,000 rads) human glioma cells and used in a short-term hyperimmunization protocol; sera obtained from this regimen were compared to those obtained by long-term hyperimmunization of macaques with complete Freund's Adjuvant (CFA) and glioma cells. Immunization with BCG-CW + either irradiated or non-irradiated human glioma cells produced a specific antibody response in non-human primates without clinical, macroscopic, or microscopic evidence of allergic encephalomyelitis.

Animals↗
PubMed1981

Heterogeneity of Genotypic and phenotypic characteristics of fifteen permanent cell lines derived from human gliomas.

Six new permanent cell lines were established from human gliomas and compared to nine other cell lines from human gliomas. All fifteen lines had individually distinct HLA phenotypes and all but two, which were from a black patient, had type B glucose-6-phosphate-de;hydrogenase isoenzymes. Morphologically, the lines could be classified into four patterns descriptively designated as fibroblastic, fascicular, epithelial, or glial. Four of the lines grew progressively and could be serially transplanted when injected into athymic mice; two others grew initially and then regressed. From none to 100% of cells developed elongated tapering processes and showed reduction in nuclear-cytoplasmic ratio in the presence of 1 mM cyclic AMP and theophylline. Levels of 2'-3' cyclic nucleotide 3'-phosphohydrolase activity ranged from nondetectable to 12.78 +/- 1.49 micromoles 2' AMP formed per hr mgm total protein. None of the lines had detectable S-100 protein, but two had readily demonstrable glial fibrillary acidic protein in indirect immunofluorescence. Fibronectin levels in spent culture supernatants ranged from undetectable levels to 21.4 micrograms/ml/10(5) cells. All but one line shared surface antigens with normal human adult or fetal brain, as detected in absorption analyses with nonhuman primate antiserum raised against glioblastoma multiforme tissue or cell line U-251 MG. Although there were many common properties of the lines, each line had a unique profile of the parameters evaluated. This heterogeneity most likely reflects the individuality of the tumors of origin and individual genotypes and capacity for a range of phenotypic expression of cells.

2',3'-Cyclic-Nucleotide Phosphodiesterases↗
PubMed1981

Relationship of in vitro morphologic and growth characteristics of established human glioma-derived cell lines to their tumorigenicity in athymic nude mice.

Fifteen permanent cell lines derived from human gliomas which are individually distinct by immunologic and biochemical criteria were evaluated to determine if morphologic or cell biologic parameters distinguished the 4 lines which were tumorigenic in athymic nude mice. By subjective morphologic appraisal, the 4 tumorigenic lines were considered "malignant" or "borderline," but 4 of the non-tumorigenic lines were also classified in this way. By objective criteria, these 15 lines varied markedly in percentage of piled-up cells, chromatin pattern, pleomorphism, nuclear to cytoplasmic ratio, number of bizarre multinucleate giant cells, presence of abnormal mitotic figures, percentage of colony formation in soft agar, saturation density, population doubling time, and absolute plating efficiency. Among these criteria, percentage of colony formation in soft agar had the highest correlation coefficiency with tumorigenicity, and when this parameter was held constant the only additional characteristic which correlated significantly (p less than .05) was the number of bizarre multinucleate giant cells. When the 11 non-tumorigenic lines were ranked by these 2 criteria, 1 non-tumorigenic line (U-251 MGsp) had greater than .95 predicted probability of tumorigenicity. Although further tumorigenicity testing may increase the number of tumorigenic lines, the lines with few "malignant" characteristics may correspond to the population resembling cells of low grade astrocytomas seen within glioblastomas. The histologic pleomorphism of human gliomas is reflected in their morphologic and cell biologic diversity in culture.

Animals↗