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T J Matthews

Publications and source records attributed to T J Matthews.

At least 127 records · Page 7Linked to original sources
PubMed1986

Partial purification and characterization of a murine glioma-associated antigen defined by syngeneic rat monoclonal antibodies.

A glioma-associated antigen was previously identified on an avian sarcoma virus-induced F-344 rat astrocytoma cell line S69-c15 by four rat monoclonal antibodies (7G4, 9F1, 10E3 and 10E7) produced after syngeneic immunization. Earlier data suggested all four antibodies reacted with a polypeptide-associated epitope. We report here that the antigen activity was detected in the supernatant of tumor homogenates and could pass through a 1000 Da molecular weight cut-off dialysis membrane, as determined by antibody binding inhibition in a cell surface radioimmunoassay. When the dialysate was fractionated by Bio-Gel P-2 chromatography, antibody inhibiting activity eluted in the range of 300-600 Da. A highly purified material was further isolated by ion exchange high pressure liquid chromatography. Parallel purification product from an antigen-negative cell line failed to demonstrate antibody inhibiting activity. We conclude that greater than 400-fold purification enrichment of antigen can be achieved. We postulate that the partially purified antigenic determinant is a glioma-associated determinant of highly restricted expression and is presented in hapten-carrier form by the glioma cells.

Animals↗
PubMed1986

Prospect for prevention of human immunodeficiency virus infection: purified 120-kDa envelope glycoprotein induces neutralizing antibody.

This study initiates an effort to develop a safe vaccine against the acquired immunodeficiency syndrome (AIDS) that is caused by infection with a retrovirus designated human immunodeficiency virus (HIV) [formerly human T-cell lymphotropic virus type III (HTLV-III)]. Other retrovirus models have shown that purified external glycoprotein subunits are immunogenic. The external envelope glycoprotein of HIV (gp120) has a molecular size of 120 kDa, is responsible for virus infectivity, and induces strong antibody response in humans. Purified HIV virus preparations contain relatively little gp120 so HIV-infected cells were used as the antigen source. The gp120 was localized on cell membranes and was solubilized with low levels of nonionic detergent. The glycoprotein was further purified by immunoaffinity chromatography over a resin prepared from IgGs isolated from patients. Homogeneity was achieved following extensive dialysis and polyacrylamide gel electrophoresis. The gp120 isolated from infected cells was shown to be structurally identical by peptide maps to virion gp120 and the amino-terminal amino acid sequence confirmed that the molecule was specified by the HIV genome. Goat, horse, and rhesus monkey (Macaca mulatta) immune sera to gp120 precipitated the homologous antigen and neutralized the in vitro infectivity of HIV. The induction of neutralizing antibody indicates that a gp120 subunit vaccine against HIV is theoretically possible.

Acquired Immunodeficiency Syndrome↗
PubMed1986

Restricted neutralization of divergent human T-lymphotropic virus type III isolates by antibodies to the major envelope glycoprotein.

By analogy to other retroviruses, the major envelope glycoprotein, gp120, of human T-lymphotropic virus type III (HTLV-III) is a probable target for neutralizing antibody. This antigen has been purified from H9 cells chronically infected with the HTLV-IIIB prototype strain. Several goats immunized with the gp120 produced antibodies that neutralized infection of H9 cells by the homologous virus isolate. These same sera failed to neutralize the divergent HTLV-IIIRF isolate. Individuals infected with HTLV-III commonly develop antibodies to gp120 that could be isolated by using the gp120 antigen coupled to an immunoadsorbent resin. The antibody fraction that bound tightly to such a resin was found to neutralize the IIIB but not the RF isolate in a similar fashion as the goat anti-gp120 sera. However, the nonbinding fraction (effluent) from the resin also contained neutralizing activity that was able to block infection by both virus isolates with similar efficacy. Human antibodies to the other virus envelope gene product, the transmembrane gp41, were also affinity purified by utilizing the recombinant peptide 121, but these failed to influence infection by either virus isolate.

Antibodies, Viral↗
PubMed1985

Immunochemical and biochemical characterization of a glioma-associated extracellular matrix glycoprotein.

A novel human glioma-associated extracellular matrix (ECM) glycoprotein has been identified by murine monoclonal antibody 81C6. The glycoprotein, designated GMEM, is expressed in the ECM of glioma and mesenchymal cell cultures, in the perivascular matrix of endothelial proliferations of human gliomas, and in the stroma of human glioma xenografts in athymic mice, where it has been used as a target antigen for monoclonal antibody tumor localization and radioimaging. We report here on the immunochemical and biochemical characterization of GMEM. Polyacrylamide gel analysis of immunoprecipitated [3H]-leucine- and [3H]-glucosamine-labeled ECM from the human glioma cell line U-251MG has shown that GMEM is a high-molecular-weight macromolecule (Mr approximately 1,000,000) composed of Mr approximately 230,000 disulfide-bonded glycoprotein subunits. Immunoprecipitation, immunoblot, and one-dimensional peptide map analysis have shown that GMEM is distinct from human fibroblast and plasma fibronectin. These results support previous immunohistology and absorption analysis findings, indicating that GMEM is distinct from fibronectin, laminin, and glycosaminoglycans secreted by U-251MG.

Antibodies, Monoclonal↗
PubMed1985

Murine in vitro antigenic modification of tumor cells: effect on susceptibility to natural cell-mediated cytotoxicity.

A 3-methylcholanthrene [(MCA) CAS: 56-49-5]-induced fibrosarcoma cell line and its Friend murine leukemia virus-infected counterpart were assessed for their susceptibility to lysis by so-called "natural" effector cells in a series of 51Cr release assays. Detailed functional and phenotypic analysis of lytic effector cell populations from normal C57BL/6 mouse spleens revealed an identity most closely associated with natural cytotoxic cells. Neither tumor cell line was found to be sensitive to natural killer-mediated lysis. Additionally, virus infection of the MCA-induced fibrosarcoma cell line did not affect susceptibility to natural cell-mediated cytotoxicity.

Animals↗
PubMed1985

Immunologic control of a retrovirus-associated murine adenocarcinoma. VI. Augmentation of antibody-dependent killing following quantitative and qualitative changes in host peritoneal cells.

Attempts were made to augment the antibody-dependent killing of the ascitic AD755a tumor in vivo to protect C57BL/6J mice against the outgrowth of larger tumor burdens. The lethal dose for this tumor is less than 100 cells, and antibodies contained in a hyperimmune antitumor serum (HIS) were found to suppress the outgrowth of a maximum of about 5 X 10(5) cells. Thioglycollate injected ip increased the number of peritoneal macrophages, potential effectors for antibody-dependent cell-mediated cytotoxicity (ADCC), by tenfold to fortyfold and raised the maximum treatable tumor challenge (MTTC) to about 4 X 10(6) cells. By comparison, ip injection of Corynebacterium parvum increased the total peritoneal cell population by only twofold but raised the MTTC to about 20 X 10(6) cells. Neither agent alone had an effect on long-term survival, even at very low tumor inocula (1 X 10(3) cells). The protective HIS is known to contain tumor-binding antibodies in each of the IgG1, IgG2A, and IgG2B isotype fractions. Although the IgG2A fraction is far superior in vivo in the suppression of tumor outgrowth, the IgG2A fraction was also found to be most effective in combination with thioglycollate treatment in agreement with the observed preference of thioglycollate-elicited macrophages for this isotype in in vitro killing assays. In contrast following C. parvum treatment, all three isoptype fractions were equally suppressive to tumor outgrowth. A second major change following C. parvum treatment was that tumor cells precoated in vitro with antibodies were effectively eliminated in vivo. The same antibody-coated cells administered to thioglycollate-treated or unmanipulated animals were uniformly lethal even at much lower tumor doses. Taken together these results suggested a major qualitative change in the antibody-dependent tumor-killing process following C. parvum treatment. This change was most likely due to the C. parvum activation of highly lytic effector cells for ADCC, the identity of which was examined in an accompanying manuscript.

Adenocarcinoma↗
PubMed1985

Immunologic control of a retrovirus-associated murine adenocarcinoma. VII. Tumor cell destruction by macrophages and IgG2A.

The mechanism by which IgG2A from a syngeneic antitumor hyperimmune serum mediates destruction of target cells in the presence of thioglycollate-elicited peritoneal macrophages was investigated by using an in vitro assay system. Labeled tumor cells were found to exhibit a biphasic pattern of binding to the effector cells; this binding pattern was dependent on the presence of specific antibody. The initial binding phase produced no apparent changes in the target cell population. Target cells coated with specific antibody exhibited a similar early binding phase, but excess free antibody was required for the subsequent binding phase and its associated release of radiolabel and cell destruction. Several features of this process observed distinguished it from more conventional forms of antibody-dependent cell-mediated cytoxicity. These included 1) the preference for antibodies of the IgG2A isotype, 2) the association of cell destruction with the release of nuclear but not cytoplasmic label, and 3) the requirement of excess free antibody for target cell killing.

Adenocarcinoma↗
PubMed1985

Immunologic control of a retrovirus-associated murine adenocarcinoma. VIII. Corynebacterium parvum-activated natural killer cells as potent antibody-dependent cell-mediated cytotoxicity effectors.

The antibody-dependent lytic activity of Corynebacterium parvum-induced peritoneal exudate cells was examined in vitro by utilizing AD755a tumor targets and a homologous anti-AD755a hyperimmune serum. Maximum antibody-dependent cell-mediated cytolysis (ADCC) of tumor targets was achieved within 4 hours of incubation. ADCC activity was found primarily in the plastic nonadherent cell population and was greatly enriched following removal of phagocytic cells by carbonyl iron. Phenotypically, the cells active in short-term ADCC were Qa-5+, ASGM-1+, Thy 1.2+, and NK 1.1+ and were unaffected by treatment with Lyt 1.2, Lyt 2.2, MAC-1, or I-Ab antibodies plus complement. Cells active in antibody-independent lysis of AD755a targets were phenotypically identical to antibody-dependent effectors. Although indicative of a natural killer (NK) cell phenotype, C. parvum-induced effectors differed from "spontaneous" splenic NK cells in their relative sensitivity to anti-Thy 1.2 as well as to anti-NK 1.1 treatment. Unlike the IgG2a-dependent lysis of AD755a-derived cells by inflammatory macrophages, all IgG isotypes of antiAD755a serum were equally effective in ADCC mediated by C. parvum NK cells. Finally, treatment of C. parvum-inoculated animals with anti-ASGM-1 serum eliminated in vitro NK activity and abrogated the in vivo therapeutic effects of hyperimmune serum. These findings, together with other correlations detailed herein, strongly suggested that C. parvum-activated NK cells appeared to represent a unique subset of NK cells that can serve as potent effectors in the antibody-dependent killing of AD755a tumor cells.

Adenocarcinoma↗
PubMed1984

Properties of mouse leukemia viruses. XIX. Effective antibody therapy of AKR leukemia occurs independently of virus neutralization and produces long-term changes in the virus status of the thymus.

Administration of high-titered goat anti-FLV gp71 IgG to AKR mice during a narrow neonatal therapy "window" suppresses the early development of MuLV infectious cell centers (ICC) in spleen, thymus, and bone marrow. By 4-5 weeks of age ICC appear in spleen and marrow cell populations, rapidly increasing to plateau levels within 2 weeks in the absence of viremia. The thymus of treated animals remains devoid of detectable ICC throughout the 4-month period of testing. This pattern of ICC suppression occurs independently of virus neutralization as shown by the inability of F(ab')2 preparations, which retained neutralizing activity, to prevent early establishment of ICC. Immune IgG significantly decreases, but does not eliminate gp71 expression in all tissues tested. In control animals, ICC reside within a minor subpopulation of cortical, thymic T cells, whereas peripheral (i.e., splenic) ICC are totally devoid of conventional T cell, B cell, and macrophage phenotypic markers. Although thymocytes appear to be a major target of this antibody therapy, T-cell reactivity is not compromised.

AKR murine leukemia virus↗
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↗