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C J Wikstrand

Publications and source records attributed to C J Wikstrand.

At least 55 records · Page 3Linked to original sources
PubMed1991

Disialoganglioside GD2 in human neuroectodermal tumor cell lines and gliomas.

Monoclonal antibodies (mAbs) recognizing the disialoganglioside II3(NeuAc)2GgOse3Cer (GD2) were produced by immunizing mice with the GD2-expressing neuroblastoma cell line LAN-1 and a prefusion boost with purified GD2 coupled to Salmonella minnesota. Two IgM mAbs were isolated which demonstrated high levels of reactivity (binding ratios in excess of 100) with GD2 by solid-phase radioimmunoassay and positivity in high-performance thin-layer chromatography (HPTLC) immunostain; only one (DMAb-20) was subsequently shown by analysis with a panel of defined ganglioside species to be specific for the minimum epitope of GD2 GalNAc beta 1-4(NeuAc alpha 2-8-NeuAc alpha 2-3)Gal-, DMAb-20 was used to evaluate the expression of GD2 by malignant glioma and medulloblastoma cell lines using cell surface radioimmunoassay. indirect membrane immunofluorescence. HPTLC immunostain, and densitometric analysis of extracted gangliosides from selected cell lines. Sixteen of 20 (80%) malignant glioma and 5 of 5 medulloblastoma cell lines reacted with DMAb-20; in agreement with previous studies, 5 of 5 neuroblastoma and 2 of 3 melanoma cell lines also reacted with DMAb-20, GD2 was proportionally increased in the glioma and medulloblastoma cell lines relative to levels in normal brain, as determined by densitometric analysis. In a phenotypic survey of malignant glioma biopsies, tumor cells in 24 of 30 (80%) cases stained positively with DMAb-20. Reactive astrocytes, both within the adjacent to tumors, were frequently intensely stained. Among the morphological variants of glioblastoma examined, the most intense staining with DMAb-20 was observed in neoplastic gemistocytes, with the weakest or absent staining in small cell glioblastomas. As GD2 is a commonly expressed surface antigen of gliomas and medulloblastomas, expression of which is retained in tissue culture. DMAb-20 will be useful in determining the functional role of GD2 in cell-cell interaction, adhesion, and invasion, and in defining altered growth control mechanisms of central nervous system neoplasms in in vitro models.

Animals↗
PubMed1991

Occurrence of lacto series gangliosides 3'-isoLM1 and 3',6'-isoLD1 in human gliomas in vitro and in vivo.

Monoclonal antibodies (MAb; DMAb, monoclonal antibodies derived at Duke Medical Center) directed against the oncofetally expressed lactotetraosyl gangliosides 3'-isoLM1 (IV3NeuAc-LcOse4Cer) and 3',6'-isoLD1 (IV3NeuAc,III6NeuAc-LcOse4Cer) were produced and their reactivity spectra compared to that of the alpha-3'-isoLM1 MAb SL-50. The IgM MAb SL-50 defines the epitope NeuAc (or NeuGc)alpha 2-3Gal beta 1-3GlcNAc, the terminal sequence of both gangliosides. SL-50 requires an unsubstituted GlcNAc residue; IgM DMAb-14 will accept the alpha 2-6 linked sialic acid to GlcNAc found in 3',6'-isoLD1. Immunohistochemical localization of 3'-isoLM1 was performed on 31 biopsy specimens of human gliomas; 15 (48%) expressed 3'-isoLM1 as defined by binding of MAb SL-50. Staining of small anaplastic cells, giant cells, and the glial component of gliosarcomas was observed. Neoplastic gemistocytes, when present, showed particularly intense staining. The 3'-isoLM1 and 3',6'-isoLD1 distribution in cultured cell lines and derived xenografts of primary tumors of the human central nervous system and of embryonal or neuroectodermal tumor derivation was determined. Six of 29 cell lines expressed 3'-isoLM1: 2/16 gliomas, 3/3 teratomas, 1/1 pancreatic adenocarcinoma. No cell line expressed detectable 3',6'-isoLD1 by immunostain analysis of ganglioside extracts. The 3'-iso-LM1-positive cell lines expressed it in xenograft form; in five xenografts, the corresponding cell lines of which were 3'-isoLM1-negative, it was a proportion of the monosialoganglioside fraction. 3',6'-isoLD1 was detected in two xenografts, D-54 MG (glioma) and PA-1 (teratoma). The demonstration of 3'-isoLM1 in gliomas in in vivo forms and the relatively infrequent expression by derived cultured cells suggest that ganglioside expression is modified by environmental forces. Expression of 3'-isoLM1 and 3',6'-isoLD1 in fetal and neonatal brain, in intense reactive astrocytosis such as polyunsaturated fatty acid lipidosis, and in primary neoplasms of the central nervous system suggests their role in cell-cell attachment during development, migration, and neoplastic transformation.

Animals↗
PubMed1991

Medulloblastoma cell-substrate interaction in vitro.

Medulloblastoma, a highly malignant pediatric tumor of the posterior fossa, demonstrates a marked propensity for leptomeningeal dissemination. Although the predominant site of relapse is the posterior fossa, the prevention of subarachnoid spread would be of significant therapeutic value. The established medulloblastoma cell lines D283 Med, D341 Med, D384 Med, D425 Med, D458 Med and Daoy have been investigated in in vitro adhesion assays for their capacity to bind to the predominant components of the leptomeningeal extracellular matrix: fibronectin, laminin and collagen IV. Growth on the reconstituted basement membrane matrix, Matrigel, was also assayed. Of the five neuronal phenotype DMed lines, all of which grow spontaneously as macrospheroids in standard fetal calf serum-containing tissue culture medium, only D425 Med and its sibline, D458 Med, derived from a subsequent sample from the same patient, displayed adherence to any of the substrata: approximately 20% of input D425 Med cells attached and exhibited cell spread and some extension (adhesion) on fibronectin. All other DMed lines failed to attach to these substrates. The glial phenotype cell line Daoy, which grows as an adherent monolayer under normal culture conditions, exhibited attachment, extension and growth on all substrata as did the glioma cell line U-251 MG and the neuroblastoma cell line SK-N-SH. The lack of attachment, and thus spread on components of the leptomeningeal extracellular matrix under in vitro assay conditions by 5/6 of the medulloblastoma cell lines investigated, is characteristic of neuronally differentiated cells, thus reinforcing the previously described neuronal phenotype of these lines. The readily demonstrated expression of N-CAM and L1 by all of the medulloblastoma cell lines suggests that the primary mode of leptomeningeal extension in vivo may be dependent on such other cell-cell and cell-substrate binding mechanisms.

Cell Adhesion↗
PubMed1991

Differentiation characteristics of newly established medulloblastoma cell lines (D384 Med, D425 Med, and D458 Med) and their transplantable xenografts.

Three new human medulloblastoma (MB) cell lines (D384 Med, D425 Med, and D458 Med) and their transplantable xenografts were examined for antigenic expression with antibodies against neuroectodermal antigens, cytoskeletal proteins, neuroendocrine markers, glioma-associated antigens, tenascin, human lymphocyte antigen molecules, epidermal growth factor receptor, and T-cell antigen by indirect immunofluorescence, avidin-biotin complex peroxidase immunohistochemistry, and immunoblot methods. We found that each of the three cell lines expressed vimentin; low-, middle-, and high-molecular-weight neurofilament proteins; and the synaptic vesicle membrane glycoprotein synaptophysin. Each of the cell lines also reacted with antibodies against neural cell adhesion molecules, but none of them were positive for antibodies against glial fibrillary acidic protein, keratin, microtubule-associated protein tau and microtubule-associated protein 2, human lymphocyte antigen-DR, epidermal growth factor receptor, and T-cell antigen. Immunoreactivities with anti-tenascin and anti-glioma-associated antibodies were variable in these cell lines. Anti-human lymphocyte antigen-A,B and anti-beta 2-microglobulin antibodies reacted with xenografts of D384 Med and D425 Med and were weakly positive for a small population of D384 Med cultured cells. In summary, the detection of neurofilament proteins and synaptophysin and the absence of glial fibrillary acidic protein provide strong evidence for a neuronal phenotype of D384 Med, D425 Med, and D458 Med.

Antigens, Neoplasm↗
PubMed1990

Gangliosides in the human glioma cell line U-118 MG grown in culture or as xenografts in nude rats.

This study was undertaken to characterize gangliosides in the human glioma cell line U-118 MG. The cell line was grown both in cell culture and as xenografts in nude rats. A common finding in both culture and xenograft cells was the high proportion of the lactoseries ganglioside 3'-LM1, approximately one third of the total ganglioside sialic acid. Otherwise, there were marked differences between the two cell sources. The cells grown in culture had a more simple ganglioside pattern than those grown in xenografts. In the latter instance, more complex gangliosides of the lactoseries, including 3'8'-LD1, sialyllactonorhexaosylceramide and a branched structure with two terminal NeuAc alpha 2-3Gal beta 1- 4GlcNAc chains, and the gangliotetraose series were found. Another marked difference involved GM2, which in the cultured cells was a major fraction, indicating that the synthesis of the gangliotetraose series gangliosides in the former stopped at the level of GM2. These results show that the ganglioside composition of a glioma cell line is strongly influenced by environmental factors.

Animals↗
PubMed1990

Determination of gangliosides in six human primary medulloblastomas.

The ganglioside composition of six human medulloblastomas was analyzed. The characterization was performed by thin-layer chromatography, sialidase hydrolysis, and immunological staining with a panel of characterized antiganglioside monoclonal antibodies. The total ganglioside content ranged from 60 to 1,130 nmol of ganglioside sialic acid/g wet weight. Neuronal gangliosides (gangliotetraose series) were found in varying amounts in all medulloblastomas. Gangliosides of the neolactotetraose series (3'-LM1 and LD1) were present in all specimens, and the lactotetraose series ganglioside 3'-isoLM1 was found in all cases showing astrocytic differentiation. This supports our previous findings that 3'-isoLM1 is a marker for proliferating astroglial cells.

Adolescent↗
PubMed1990

Circulating glycoconjugates in CSF of meningioma patients.

This study investigated whether tumor-associated gangliosides or glycoproteins may be markers for meningiomas in CSF. The concentrations of a number of gangliosides and sulphatide were determined with specific monoclonal antibodies and cholera toxin B-subunit in a thin-layer chromatography overlay technique. As compared to a reference group of 10 individuals (mean age 50 +/- 14 years), the CSF samples from 7 meningioma patients (mean age 55 +/- 12 years) were found to contain significantly increased concentrations of ganglioside GD3 [II3(NeuAc)2-LacCer], one of the major gangliosides in meningioma tissue specimens. Sulphatide was significantly increased in 6 of 7 patients. Tumor-associated glycoproteins detected by the lectin Ricinus communis 1 in meningioma tissue specimens, but not in normal human brain tissue, were also found in the CSF of the meningioma patients. An early diagnosis of meningiomas might be achieved by the combined assay in CSF of ganglioside GD3 and glycoproteins with Ricinus communis lectin.

Antibodies, Monoclonal↗
PubMed1989

Five new epitope-defined monoclonal antibodies reactive with GM2 and human glioma and medulloblastoma cell lines.

In order to investigate GM2 expression in gliomas, the GM2-positive human glioma cell line (HGL) D-54 MG, which contains 0.6 nmol GM2/mg protein, representing 77% of the total monosialoganglioside fraction, was used as an immunogen for the production of anti-GM2 monoclonal antibodies. For ganglioside designations, see IUPAC-IUB (Eur. J. Biochem., 79: 11-21, 1977) and Svennerholm (J. Neurochem., 10: 613-623, 1963). Five IgM monoclonal antibodies (DMAb-1 through DMAb-5) specifically recognizing the GalNAc beta1-4(NeuAc alpha 2-3)Gal-terminal epitope common to GM2 and GalNAC-GD1a are reported. The antibodies did not react with GM1, GM3, GD2, GD3, GD1a, GD1b, and GQ1b. Purified anti-GM2 MAbs were used to define the expression of the "GM2" terminal epitope by cultured human malignant and normal cells by radioimmunoassay and membrane immunofluorescence. Among neuroectodermal tissue-derived cell lines, DMAb-3, at an optimal concentration of 5 micrograms/ml, showed high reactivity (radioimmunoassay binding ratios greater than 20) with 9 of 19 HGLs, 3 of 5 medulloblastoma, 4 of 5 neuroblastoma, and 1 of 3 melanoma lines. Moderate reactivity (binding ratio, 10-20) was exhibited by 3 HGL, 2 medulloblastoma, and 1 neuroblastoma lines and low reactivity (binding ratio, 3-10) by 5 HGL lines; no reactivity was detected with 2 HGL and 2 melanoma lines. Densitometric evaluation of monosialoganglioside extracts from human glioma and medulloblastoma cell lines in conjunction with immunostaining on thin-layer chromatograms showed that GM2 represents the major monosialoganglioside in 8 of 10 HGL and in 3 of 4 Med lines. In these lines the amount of GM2 ranged from less than 0.1 to 0.6 nmol/mg protein. These results indicate that GM2 represents a proportionally increased ganglioside of most glioma, medulloblastoma, and neuroblastoma cells in vitro.

Antibodies, Monoclonal↗
PubMed1989

A new ganglioside of the lactotetraose series, GalNAc-3'-isoLM1, detected in human meconium.

A monoclonal antibody produced by immunization with cells of the human glioma cell line D-54 MG reacted with ganglioside GM2. The binding epitope of the antibody was found to be GalNAc beta 1-4(NeuAc alpha 2-3)Gal. Immunological detection of glycolipid antigens on thin-layer plates with this monoclonal antibody, DMAb-1, revealed the presence of a new ganglioside. This ganglioside, co-migrating with NeuAc alpha 2-6Gal beta 1-4GlcNAc beta 1-3Gal beta 1-4Glc beta 1-1Cer(6'-LM1) and GalNAc beta 1-4(NeuAc alpha 2-3)Gal beta 1-3GalNAc beta 1-4Gla beta 1-4Glc beta 1-1Cer (GalNAc-isoGM1) at chromatographic separation was isolated from human meconium. Its structure was determined by permethylation and fast atom bombardment-mass spectometry analyses. The new ganglioside was found to be a combination of the lacto and ganglio series gangliosides, and the structure found to be GalNAc beta 1-4(NeuAc alpha 2-3)Gal beta 1-3GlcNAc alpha 1-3Gal beta 1-4Glc beta 1-1Cer(GalNAc-3'-isoLM1).

Antibodies, Monoclonal↗
PubMed1989

GD3 expression by cultured human tumor cells of neuroectodermal origin.

Seven monoclonal antibodies (mAbs) reactive with ganglioside II3(NeuAc)2-LacCer (GD3) were generated; four of these mAbs (DMAb-21, DMAb-22, DMAb-23, and DMAb-24) by immunizing mice with GD3 adsorbed to Salmonella minnesota and the remaining three (DMAb-7, DMAb-8, and DMAb-17) with melanoma line SK-MEL 28, which contains 1.4 nmol sialic acid of GD3 per mg protein. The specificities of the mAbs were defined by high-performance thin-layer chromatography (HPTLC) immunostain and solid-phase radioimmunoassay (SP-RIA) with a panel of purified gangliosides. DMAb-7 and DMAb-8 reacted with GD3, IV3(NeuAc)2nLcOse4Cer(3',8'-LD1), and very weakly with IV3(NeuAc)2II3NeuAcGgOse4Cer (GT1a), but not with II3NeuAc-LacCer (GM3), II3NeuAcGgOse3Cer(GM2), II3NeuAcGgOse4Cer (GM1), II3NeuAc, IV3NeuAcGgOse4Cer (GD1a), II3(NeuAc)2GgOse3(GD2), II3(NeuAc)2GgOse4Cer (GD1b), IV3NeuAcII3(NeuAc)2, GgOse4Cer(GT1b), suggesting the binding epitope to be a terminal tetrasaccharide NeuAc alpha 2-8NeuAc alpha 2-3Gal beta 1-4(Glc or GlcNAc). DMAb-7 and DMAb-8 were used to investigate the expression of GD3 on cultured human tumor cells of neuroectodermal origin. Thirteen of 19 gliomas, 3 of 5 medulloblastomas, 5 of 5 neuroblastomas, 2 of 2 melanomas, and 1 of 3 teratomas were shown to react with DMAb-8 and/or DMAb-7 by cell surface-RIA (CS-RIA) and immunofluorescence (IF) assays. HPTLC and densitometric analysis confirmed these results, as positive immunostains in the GD3 region were obtained with oligoganglioside fractions from 9 glioma, 1 medulloblastoma, 2 neuroblastoma, 1 melanoma, and 1 teratoma cell line. Glioma cell line U-105 MG and medulloblastoma cell line Daoy contain GD3 as shown by HPTLC immunostain analysis of extracts, although GD3 was undetectable on the cell surface as determined by CS-RIA and IF.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

Ganglioside mapping of a human medulloblastoma xenograft.

The ganglioside patterns of medulloblastomas have never been established; in this study we report the ganglioside profile of the human medulloblastoma cell line TE-671 grown as a xenograft in nude mice. Gangliosides were isolated and structurally analyzed by fast atom bombardment mass spectometry following permethylation. Identification of individual gangliosides was also performed by immunostaining of high-performance thin-layer chromatography-separated bands. Total ganglioside levels of 0.20 mumol/g of tissue were obtained, consistent with those reported for human glioma cell lines grown as xenografts; predominant monosialogangliosides of TE-671 xenografts were II3-alpha-NeuAc-LacCer (GM3) and II3-alpha-NeuAc-GgOse3Cer (GM2) but there were also relatively large proportions of IV3-alpha-NeuAc-LcOse4Cer (3'-isoLM1), IV3-alpha-NeuAc-nLcOse4Cer (3'-LM1) and a further ganglioside of the neolacto-series with an extra lactosamine moiety. The only oligosialoganglioside detected was IV3, II3-alpha-NeuAc2-GgOse4Cer (GD1a).

Animals↗
PubMed1989

Phenotypic analysis of four human medulloblastoma cell lines and transplantable xenografts.

An extensive panel of monoclonal antibodies (MAb) and monospecific antisera reactive against neuroectodermal-, neuronal-, glial-, and lymphoid-associated antigens, extracellular matrix, HLA, and cell-surface receptors was used to characterize the phenotype of four continuous, karyotypically distinct medulloblastoma cell lines and transplantable xenografts. All four cell lines demonstrated significant reactivity with anti-neuroectodermal-associated MAb. No apparent pattern of reactivity with anti-lymphoid MAb was seen; notably, there was a uniform absence of detectable Thy-1. Review of the complete antibody reactivity profile revealed a dichotomy between lines TE-671 and Daoy and lines D283 Med and D341 Med, which have been previously shown to express neurofilament protein in culture and xenografts, and to exhibit neuroblastic morphological features in biopsy and xenograft tissue sections. TE-671 and Daoy reacted with the MAb directed against tenascin, epidermal growth factor (EGF) receptor, HLA-A,B epitopes, beta 2-microglobulin and 5/8 of the glioma-associated antigens, but did not react with the anti-neurofilament protein (NFP) MAb. D283 Med and D341 Med expressed NFP but did not react with MAb against tenascin, EGF receptor, HLA-A,B epitopes, beta 2-microglobulin or 6/8 and 7/8 (respectively) of the glioma-associated antigens. The observed phenotypic differences provide a conceptual framework for investigating basic differences in the biological behavior of medulloblastoma. Moreover, the subdivisions can be evaluated for prospective value in tissue diagnosis, cerebrospinal fluid cytology and antibody-mediated imaging and therapy.

Animals↗
PubMed1989

Neurofilament protein crosslinking in gamma-diketone neuropathy: in vitro and in vivo studies using the seaworm myxicola infundibulum.

Neurofilament (NF) protein crosslinking has been proposed as the ultimate pathogenetic mechanism underlying the neuropathies caused by the gamma-diketones 2,5-hexanedione (HD) and 3,4-dimethyl-2,5-hexanedione (DMHD). Mammalian models have been used to investigate this hypothesis, but alternative experimental models are needed. Myxicola infundibulum is a marine worm which is gaining popularity in neuroscience research because of its large syncytial axon. A model system using Myxicola has been developed to investigate NF crosslinking in worms exposed to neurotoxic agents whose putative mechanisms involve covalent crosslinking of NF proteins. In vitro studies using purified NF demonstrate that progressive alkylation of Myxicola NF with [2,5-14C]DMHD is accompanied by NF protein crosslinking. Rabbit anti-Myxicola NF antisera showed highly restricted activity for Myxicola axoplasm and NF and were employed for immunoblotting axoplasm from Myxicola treated in vivo with DMHD. A dramatic increase in high molecular weight material was demonstrated in the axoplasm of treated worms, as demonstrated by polyacrylamide gel electrophoresis, and the new high molecular weight bands stained with the anti-NF antisera, indicating the presence of anti-NF reactive material in the crosslinked protein. Further, there was progression of crosslinking after cessation of exposure in vivo, an observation which suggests oxidation of remaining pyrrolyl derivatives. These studies support previous observations which suggest that NF crosslinking is the molecular event which initiates NF aggregation in gamma-diketone neurotoxicity, and establish Myxicola infundibulum as a useful species in which to study certain neurotoxic compounds.

Alkylation↗
PubMed1988

Therapeutic efficacy of antiglioma mesenchymal extracellular matrix 131I-radiolabeled murine monoclonal antibody in a human glioma xenograft model.

The development of Mabs, particularly those reactive with primary brain tumors but not with normal brain, provides a potential means of delivering therapeutic agents selectively to human malignant gliomas. Mab 81C6, an IgG2b immunoglobulin, which defines an epitope of the glioma-associated extracellular matrix protein tenascin, has been shown to bind to human glioma cell lines, glioma xenografts in nude mice, and primary human gliomas, but not to normal adult or fetal brain. To test the therapeutic potential of this Mab for targeted delivery of isotopes, nude mice bearing progressively growing s.c. xenografts of D-54 MG, a human glioma cell line, were given injections via the tail vein of either buffer, unlabeled 81C6, 131I-labeled 81C6, or 131I-labeled 45.6, a nonspecific control Mab of the same isotype. Specific activities of the Mab range from 6.0 to 15.5 mCi/mg with protein doses from 7.6 to 167 micrograms. The doses given by injection per animal for labeled 81C6 were 50, 250, 500, and 1000 mu Ci and 500 and 1000 mu Ci for 45.6. Tumor response was measured by growth delay in reaching 1000 or 5000 mm3 tumor volumes using the Wilcoxon rank sum test, and by comparing the proportion of tumors that had regression in volume after treatment using the Fisher exact test. Statistically significant growth delays at 1000 mm3 were noted in 1 of 3 experiments with 500 mu Ci 81C6 (P less than 0.001) and 2 of 3 for 1000 mu Ci 81C6 (P = 0.001 and less than 0.001). At 5000 mm3, statistically significant growth delays were seen with radiolabeled 81C6 in 2 of 2 experiments at 250 mu Ci (P = 0.01 and 0.02), 4 of 4 at 500 mu Ci (P = 0.03-less than 0.001), and 2 of 2 at 1000 mu Ci (P = less than or equal to 0.001) and with radiolabeled 45.6 in 1 of 1 at 1000 mu Ci (P = 0.01). The percentage of animals with tumor regression progressively increased with increasing doses of isotope. For radiolabeled 45.6, there were 0 of 10 regressors at 500 and 1 of 10 at 1000 mu Ci. For radiolabeled 81C6, there were 0 of 6 regressors at 50 mu Ci, 1 of 16 (6%) at 250 mu Ci, 7 of 38 (18%) at 500, and 15 of 28 (54%) at 1000 mu Ci. Statistically significant tumor regression was seen only at doses of 500 and 1000 mu Ci of 131I-81C6.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1988

Phenotypic and genotypic analysis of a human medulloblastoma cell line and transplantable xenograft (D341 Med) demonstrating amplification of c-myc.

D341 Med is a new continuous cell line and transplantable xenograft derived from a cerebellar medulloblastoma. This line grew in vitro in suspension culture with spontaneous macroscopic spheroid formation and demonstrated 20-fold amplification of c-myc. Cultured D341 Med cells injected subcutaneously into athymic mice grew as markedly cellular, highly invasive undifferentiated neoplasms. Intracranial tumors grew as markedly cellular mitotically active neoplasms largely located within the subarachnoid space or lining the ventricular system. Immunocytochemical analysis of the cell line and SQ tumors revealed the high (NFP-H) and middle (NFP-M) molecular weight (Mr) neurofilament proteins (NFPs). Immunoblots demonstrated the presence of molecular species that co-migrated with authentic human NFP-H and NFP-M. This cell line and transplantable xenograft may allow, in conjunction with the authors' other models of human medulloblastoma, analysis of the heterogeneous biologic properties and therapeutic sensitivity of this tumor.

Animals↗
PubMed1987

Comparison of monoclonal antibody delivery to intracranial glioma xenografts by intravenous and intracarotid administration.

Monoclonal antibody 81C6, which is directed against a human gliomamesenchymal extracellular matrix antigen, was used to evaluate the potential advantage of intracarotid (i.c.) administration versus i.v. delivery to D-54 MG human glioma intracranial xenografts in immunosuppressed rats. Two approaches were taken. In paired-label analysis, 125I-labeled 81C6 and 131I-labeled isotype control antibody were given to separate groups of animals by either the i.v. or i.c. route. Biodistribution measurements as a function of time were analyzed in terms of the percentage of injected dose/g of tissue and localization indices. No significant difference (P greater than 0.19 to P greater than 0.56) was demonstrated between the i.v. and i.c. routes. To control for the large localization variation inherent in the animal model used, an alternative experimental design, paired-injection analysis, was performed in which 125I- and 131I-labeled 81C6 were simultaneously administered by the i.c. and i.v. routes to the same animal. Significantly higher levels of percentage of dose/g of tissue and localization ratios (P less than 0.05 to P less than 0.005) were shown from Day 1 to Day 3 for 81C6 given i.c. Approximately 20% more antibody was delivered to the D-54 MG intracranial tumor by the i.c. route during the experimental period of 5 days. No difference in the levels of normal tissue exposure between the two routes of administration was seen. These data suggest an advantage exists for whole monoclonal antibody given i.c. and that, theoretically, a greater advantage may be present for smaller molecules such as Fab and F(ab')2 fragments.

Animals↗
PubMed1987

Comparative localization of glioma-reactive monoclonal antibodies in vivo in an athymic mouse human glioma xenograft model.

Radioiodinated murine monoclonal antibodies (Mabs) 81C6, Me 1-14, C12, D12, and E9, made against or reactive with human gliomas but not normal brain, and Mab UJ13A, a pan-neuroectodermal Mab reactive with normal human glial and neural cells, were evaluated in paired label studies in the D-54 MG subcutaneous human glioma xenograft model system in nude mice. Following intravenous injection in the tail vein of mice bearing 200-400 mm3 tumors, specific localization of Mabs to tumor over time (6 h-9 days) was evaluated by tissue counting; each Mab demonstrated a unique localization profile. The comparison of localization indices (LI), determined as a ratio of tissue level of Mab to control immunoglobulin with simultaneous correction for blood levels of each, showed Mabs 81C6 and Me 1-14 to steadily accumulate in glioma xenografts, maintaining LI from 5-20 at 7-9 days after Mab injection. Mab UJ13A peaked at day 1, maintaining this level through day 2, and declining thereafter. Mabs D12 and C12 peaked at days 3 and 4, respectively, and E9 maintained an LI of greater than 3 from days 3-9. Percent injected dose localized/g of tumor varied from a peak high of 16% (81C6) to a low of 5% (Me 1-14 and UJ13A). Immunoperoxidase histochemistry, performed with each Mab on a battery of primary human brain neoplasms, revealed that Mabs 81C6 and E9, which demonstrated the highest levels of percent injected dose localized/g of tumor over time, reacted with antigens expressed in the extracellular matrix. This finding suggests that extracellular matrix localization of antigen represents a biologically significant factor affecting localization and/or binding in the xenograft model used. The demonstration of significant localization, varied kinetics and patterns of localization of this localizing Mab panel warrants their continued investigation as potential imaging and therapeutic agents for human trials.

Animals↗