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R A Reisfeld

Publications and source records attributed to R A Reisfeld.

At least 109 records · Page 6Linked to original sources
PubMed1992

Phase I trial of the chimeric anti-GD2 monoclonal antibody ch14.18 in patients with malignant melanoma.

The chimeric monoclonal anti-GD2 antibody ch14.18 is made up of the variable region of the murine anti-GD2 antibody 14.18 (or its IgG2a switch variant 14G2a) and the constant region of human IgG1k. Ch14.18 mediates antibody dependent cytotoxicity and complement dependent lysis in vitro. In a phase I trial, 13 patients with metastatic melanoma received ch14.18 as a single dose of 5-100 mg. Therapy was associated with an infusion-related abdominal/pelvic pain syndrome, which required intravenous morphine for control. The pharmacokinetics of ch14.18 best fit a two-compartment model with a T1/2 alpha of 24 +/- 1 hr and a T1/2 beta of 181 +/- 73 hr. Eight of 13 patients developed a weak-modest antibody response directed at the variable region of ch14.18. Clinical antitumor responses were not observed at the doses employed in this study. However, patients receiving greater than 45 mg of ch14.18 had antibody detectable on tumor cells analyzed by fluorescent activated cell sorter. Further modification of the therapeutic regime employing larger doses and frequent administration of ch14.18 are planned.

Adult↗
PubMed1992

Monoclonal antibodies in cancer immunotherapy.

The preceding article focused on some novel approaches for the adjuvant treatment of human melanoma and neuroblastoma with mAbs against antigens preferentially expressed on these tumors. It should be emphasized that the major goal of the immunotherapy modalities described here is to apply them in an adjuvant setting for the treatment of micrometastases. The major aim is to decrease the rate of development of metastases in a setting of very low tumor burden and ultimately achieve a prolongation in life span. The combination of powerful modern technologies achieving genetic engineering of mAbs, resulting in more human-like molecules, will lead to a reevaluation of these reagents alone or in combination with molecularly defined cytokines and growth factors for the immunotherapy of cancer. The initial, albeit anectodal, findings, of phase I clinical trials mentioned in this article lead to cautious optimism that immunotherapy may find a place and will eventually contribute to the adjuvant treatment of cancer.

Antibodies, Monoclonal↗
PubMed1991

Correlation of chondroitin sulfate proteoglycan expression on proliferating brain capillary endothelial cells with the malignant phenotype of astroglial cells.

Human glioblastomas (five of five), the most malignant astroglial-derived tumors, specifically express a chondroitin sulfate proteoglycan that is recognized by monoclonal antibody 9.2.27 and localized to the glioma cell surface, proliferating endothelial cells, and the perivascular extracellular matrix within the tumor bed. In contrast, the expression of this proteoglycan in normal adult neocortex and white matter is limited to the smooth muscle of small arteries, while normal glia, endothelial cells, and endothelial cell basement membranes are nonreactive. Moreover, two anaplastic astrocytomas, representing medium-grade astroglial-derived tumors, fail to react with monoclonal antibody 9.2.27. In culture, glioblastoma and capillary brain endothelial cells specifically synthesize a 250-kDa core protein and a high-molecular-mass chondroitin sulfate proteoglycan, recognized by monoclonal antibody 9.2.27. These data suggest a correlation between the expression of this chondroitin sulfate proteoglycan on proliferating brain capillary endothelial cells and the malignant phenotype of astroglial cells. The prominent perivascular localization of chondroitin sulfate proteoglycan makes it a marker for both proliferating brain capillary endothelial cells and the most malignant transformed astroglial cells, thus providing an ideal target for the immunotherapy of glioblastoma.

Antibodies, Monoclonal↗
PubMed1991

Suppression of spontaneous melanoma metastasis in scid mice with an antibody to the epidermal growth factor receptor.

The human melanoma cell line M24met metastasizes spontaneously from s.c. tumors to multiple distant sites in mice with severe combined immunodeficiency. Metastasis to lymph nodes and lungs is found in 100% of the animals. M24met has an undifferentiated phenotype and extra copies of the short arm of chromosome 7. This cell line expresses the epidermal growth factor receptor, and 425.3, a monoclonal antibody to the epidermal growth factor receptor, binds to 291,000 receptor molecules per M24met cell with a KD of 2.3 x 10(-10) M. This antibody has no effect on the proliferation of M24met cells under tissue culture conditions and does not mediate effector cell or complement-dependent cytotoxicity of these cells in vitro. However, treatment of established s.c. M24met tumors in mice with severe combined immunodeficiency with monoclonal antibody 425.3 specifically suppresses spontaneous metastasis of these tumors. Total doses of 4, 2, and 1 mg antibody per mouse decrease the number and size of melanoma metastases and prolong the life span of treated animals. Treatment with 4 mg of the F(ab')2 fragment of monoclonal antibody 425.3 does not influence M24met melanoma metastasis, implying a significant contribution of the Fc portion to the antimetastatic effect of this antibody.

Animals↗
PubMed1991

Effect of a chimeric anti-ganglioside GD2 antibody on cell-mediated lysis of human neuroblastoma cells.

An anti-GD2 ganglioside human/mouse chimeric monoclonal antibody, ch14.18, like its murine counterpart, 14.G2a, was shown to bind to human neuroblastoma cells. This chimeric antibody proved to be more effective than 14.G2a in mediating the lysis of neuroblastoma cells with human effector cells, such as granulocytes and natural killer cells within the peripheral blood mononuclear cell population. A comparison of these two effector cell populations isolated from the same donor revealed granulocytes to be more effective than peripheral blood mononuclear cells in lysing neuroblastoma cells, which were coated with monoclonal antibody ch14.18. Addition of recombinant human granulocyte-macrophage colony-stimulatory factor increased ch14.18-mediated lysis of neuroblastoma cells by granulocytes but not by peripheral blood mononuclear cells. In fact, granulocytes were effective in mediating lysis of neuroblastoma cells coated with ch14.18 irrespective of whether they were obtained from normal adults or from neuroblastoma patients.

Animals↗
PubMed1991

Target cell-induced T cell activation with bi- and trispecific antibody fragments.

Previously we proposed a concept for tumor immunotherapy in which two different bispecific antibody conjugates, an anti-target x anti-CD3 and an anti-target x anti-CD28 conjugate, induce the activation of resting human T cells upon binding to the respective tumor target cells. After in vivo application of these reagents, this model of a "target cell-induced T cell activation" envisages the destruction of target cells by in situ activated T cells. Obviously however, for in vivo application, the use of Fc-free antibody fragments is mandatory to prevent binding of the conjugates to Fc receptor-positive cells which would lead to Fc-mediated T cell activation. Here we report a simplification of published procedures for the generation of bispecific Fab-hybrid fragments, univalent for each antigen. We demonstrate that an anti-target x anti-CD3/anti-target x anti-CD28 combination of such hybrids, as well as an identical combination of covalently coupled F(ab')2 fragments, mediate "target cell-induced T cell activation" in an in vitro test system. Thus, these reagents may be capable of inducing an in situ activation of human T cells upon systemic in vivo application according to the concept outlined above. A trispecific conjugate with anti-target, anti-CD3- and anti-CD28 specificity appears to be unsuitable for this purpose because it activates resting T cells in soluble form without requiring immobilization through binding via its anti-target portion.

Antibodies, Monoclonal↗
PubMed1991

Potential of the scid mouse as a host for human tumors.

Animal models of human tumors and their metastases that effectively mimic clinical disease are in considerable demand. While it is certainly true that athymic nude mice provide us with useful models to study a large number of human tumors in vivo, it is also well known that nude mice usually do not develop spontaneous metastases and are not suitable for all types of tumors. Therefore, the scid mouse that allows disseminated growths for a number of human tumors, particularly hematologic disorders and malignant melanoma, can be used preferentially for the investigation of such malignancies. The potential to study the interaction of human immune cells and human tumor in an in vivo model is another unique feature of scid mice that will add to their usefulness in experimental cancer research.

Animals↗
PubMed1991

A potent and specific immunotoxin for tumor cells expressing disialoganglioside GD2.

Monoclonal antibody 14G2a (anti-GD2) reacts with cell lines and tumor tissues of neuroectodermal origin that express disialoganglioside GD2. mAb 14G2a was coupled to the ribosome-inactivating plant toxin gelonin with the heterobifunctional cross-linking reagent N-succinimidyl-3(2-pyridyldithio)propionate. The activity of the immunotoxin was assessed by a cell-free translation assay that confirmed the presence of active gelonin coupled to 14G2a. Data from an enzyme-linked immunosorbent assay demonstrated the specificity and immunoreactivity of the 14G2a-gelonin immunotoxin, which was identical to that of native 14G2a. Assays for complement-dependent cytotoxicity (CDC) and antibody-dependent cellular cytotoxicity (ADCC) revealed that these functional properties of the native 14G2a antibody were also preserved in the 14G2a-gelonin immunotoxin. The gelonin-14G2a immunotoxin was directly cytotoxic to human melanoma (A375-M and AAB-527) cells and was 1000-fold more active than native gelonin in inhibiting the growth of human melanoma cells in vitro. The augmentation of tumor cell killing of 14G2a-gelonin immunotoxin was examined with several lysosomotropic compounds. Chloroquine and monensin, when combined with 14G2a-gelonin immunotoxin, augmented its cytotoxicity more than 10-fold. Biological response modifiers such as tumor necrosis factor alpha and interferon alpha and chemotherapeutic agents such as cisplatinum and N,N'-bis(2-chloroethyl)-N-nitrosourea (carmustine) augmented the cytotoxicity of 14G2a-gelonin 4- to 5-fold. The results of these studies suggest that 14G2a-gelonin may operate directly by both cytotoxic efforts and indirectly by mediating both ADCC and CDC activity against tumor cells; thus it may prove useful in the future for therapy of human neuroectodermal tumors.

Antibodies, Monoclonal↗
PubMed1991

Bispecific-monoclonal-antibody-directed lysis of ovarian carcinoma cells by activated human T lymphocytes.

Two different bispecific hybrid antibodies were established by fusing a hybridoma producing monoclonal antibody (mAb) against the pancarcinoma antigen KS1/4 with either of the two hybridomas OKT3 and 9.3, secreting antibodies reactive with the T cell determinants CD3 and CD28, respectively. The KS1/4 antibody reacts with a 40-kDa cell-surface glycoprotein antigen that is expressed on the surface of a variety of adenocarcinoma cells, including ovarian carcinoma. The ability of the bispecific antibodies 9.3 x KS1/4 and OKT3 x KS1/4 to direct peripheral blood mononuclear cells (PBMC) specifically against OVCAR-3 ovarian carcinoma target cells was measured in a 4-h 51Cr-release assay. The bispecific antibodies were four to six times more potent in killing the OVCAR-3 target cells when compared to their parental antibodies either alone or in combination. A dose-dependent response was observed in the 10-10,000 ng/ml range. The specificity of the targeting was demonstrated by the complete inhibition of cytotoxic activity following pre-incubation of tumor target cells with the parental mAb and by the lack of killing of KS1/4-negative target cell lines. An evaluation of the efficacy of PBMC from ovarian cancer patients as effector cells revealed that their specific cytotoxicity against OVCAR-3 cells was enhanced severalfold by bispecific antibodies as compared to parental antibodies. Furthermore, stimulation of PBMC with immobilized CD3 and interleukin-2 for 4 days resulted in an enhanced directed killing of human ovarian carcinoma cells by human T effector cells and the bispecific antibodies.

Antibodies, Monoclonal↗
PubMed1991

Application of the murine anti-Gd-2 antibody 14.Gd-2a for diagnosis and therapy of neuroblastoma.

We have tested the sialoganglioside monoclonal antibody Gd-2a for scintigraphic diagnostic and for immunotherapy in children with neuroblastoma stage IV. We could confirm tumor sites with Gd-2a scans in 1/2 children. Doses of 20-60 mg/m2 were administered daily for 5-10 days. 2/2 children with multiple tumor sites showed significant tumor regression. Four children, treated preventively, are still in clinical remission. One child showed tumor progression despite Gd-2a treatment. Adverse effects included itching, rashes, and pain.

Adolescent↗
PubMed1991

Aglycosylated chimeric mouse/human IgG1 antibody retains some effector function.

The N-linked carbohydrate attachment site of human IgG1 Ab has been eliminated by site-directed mutagenesis. Effector functions of aglycosylated Ab was then compared to its native counterpart. Aglycosylated Ab failed to exhibit any ADCC activity, but a significant level of CDC activity was retained by the aglycosylated Ab. These observations differ from those reported previously. Serum half-life and biodistribution of aglycosylated Ab in mice were comparable to the native Ab. Together, these results show that some, but not all, effector functions of a human IgG1 Ab are affected by aglycosylation.

Amino Acid Sequence↗
PubMed1991

Expression of genetically engineered immunoconjugates of lymphotoxin and a chimeric anti-ganglioside GD2 antibody.

Human lymphotoxin was genetically conjugated to the constant region of a human gamma 1 immunoglobulin gene at the end of either the second (CH2-LT) or third (CH3-LT) constant region domain. The altered heavy chain constant regions were combined in a plasmid vector together with the variable regions of a mouse anti-ganglioside GD2 antibody 14.18 and the human kappa constant region. The resulting immunoconjugate constructs were expressed in transfected hybridoma cells and tested for both their antibody and lymphotoxin activities. The two constructs were assembled to varying degrees depending on whether the third heavy chain constant region was present. Both forms retained their ability to bind antigen and mediate ADCC but only CH3-LT was able to mediate the lysis of melanoma target cells in the presence of human complement. Lymphotoxin activity, as defined in a cytolytic assay with mouse fibroblasts, was found to increase significantly as a function of heavy chain assembly and to be equivalent to unconjugated lymphotoxin. Neither of the constructs were cytotoxic for antigen-bearing melanoma cells that are normally resistant to lymphotoxin and tumor necrosis factor alpha. Such immunoconjugates may prove useful in targeting cytokines to the site of antigen-bearing cells in vivo. In this case, as a means of eliciting an inflammatory response at the site of a solid tumor.

Animals↗
PubMed1990

Increased lysis of melanoma by in vivo-elicited human lymphokine-activated killer cells after addition of antiganglioside antibodies in vitro.

Thirty-nine melanoma patients were treated with cyclophosphamide (350 mg/m2) followed 3 days later by 5 daily doses of interleukin 2 (3.6 million units/m2 i.v.) weekly for 2 weeks. This cycle was repeated at least twice with a 1-week interval between cycles. Natural killer and lymphokine-activated killer (LAK) cell activity in peripheral blood mononuclear cells were measured before treatment and on the last day of each cycle by chromium release assays. Development of LAK activity of greater than 10 lytic units was correlated with a clinical response. There was no correlation between natural killer activity and clinical response. Antibody-dependent cell-mediated cytotoxicity of in vivo-induced LAK cells after the addition of mouse monoclonal antibodies (MAbs) in vitro was measured in 30 cases on the last day of each interleukin 2 cycle. Anti-GD3 MAbs MB3.6, 11C64, 6H4, and R24 increased LAK cell cytotoxicity against GD3-positive GD2 melanoma cells while anti-GD2 MAb 14.18 increased LAK cell cytotoxicity against GD3-negative GD2-positive melanoma cells. MAb 9.2.27 (IgG2a) directed against a chondroitin sulfate proteoglycan and its core protein with a molecular weight of 250,000 (p250) on human melanoma cells did not mediate antibody-dependent cell-mediated cytotoxicity. The effector cells in these antibody-dependent cell-mediated cytotoxicity. The effector cells in these antibody-dependent cell-mediated cytotoxicity reactions were Leu-19 positive. In preincubation experiments the MAbs showed superior binding to the melanoma target cells than to effector cells. Our results show that low dose interleukin 2 preceded by low dose cyclophosphamide effectively induces LAK cells in vivo. The cytotoxicity of these in vivo-activated LAK cells can be augmented in vitro by mouse MAbs against glycolipid antigens on the tumor.

Antibodies, Monoclonal↗
PubMed1990

Augmentation of antibody dependent cell mediated cytotoxicity following in vivo therapy with recombinant interleukin 2.

Monoclonal antibodies (mAB) with tumor specificity are able to enhance the immunological specificity of interleukin 2 (IL-2)-activated lymphokine activated killer (LAK) cells. Antibodies may also be used to broaden the range of tumor types susceptible to immune mediated cytotoxicity by the activated LAK cells. In these studies, mAB with relative tumor specificity were used to target immunologically activated effector cells in an in vitro antibody dependent cell mediated cytotoxicity (ADCC) assay. The mAB included: 3F8 and 14.G2a, which are both specific for neuroblastoma and melanoma and recognize ganglioside GD2, and mAB ING-1, a mouse-human chimeric antibody with constant regions from human IgG1 and kappa chains and variable regions from a mouse mAB that binds to a broad range of human adenocarcinomas. Each of these mAB was able to mediate ADCC with fresh effector cells and antibody binding targets. When peripheral blood mononuclear cells were obtained from cancer patients prior to and following in vivo therapy with interleukin 2, a significant increase was noted in ADCC activity by peripheral blood mononuclear cells obtained following IL-2 therapy. Inclusion of IL-2 in the medium during the cytotoxic assay with mAB further boosted ADCC. The total activity seen was often greater than the sum of the independent LAK activity and standard ADCC activity. The cells responsible for this ADCC had the CD16+ Fc receptor. Combining IL-2 with mAB in clinical tumor therapy may lead to a wider range of tumor types being responsive to immunotherapy and may also enhance the efficacy of therapy by specifically targeting activated effector cells to tumor cells recognized by mAB. Our results provide strong support for the testing of these hypotheses in clinical trials by combining in vivo treatment with IL-2 and mAB able to mediate ADCC.

Antibodies, Monoclonal↗
PubMed1990

Biosynthesis and glycosylation of the carcinoma-associated antigen recognized by monoclonal antibody KS1/4.

Monoclonal antibody KS1/4 recognizes an epitope expressed on the cell surface of human adenocarcinoma cells and certain epithelia. Western blotting analyses of tumor cell extracts utilizing KS1/4 reveal staining of a major Mr 40,000 band and a minor Mr 42,000 band. Both components are also detectable in KS1/4 immunoprecipitates of L-[35S]methionine- and D-[3H]glucosamine-labeled human lung tumor cell extracts. When synthesis occurs in the presence of tunicamycin or when the immunoprecipitates are treated with peptide:N-glycosidase F, a single polypeptide component (Mr 37,000) is precipitated. Immediately following translation, digestion of Mr 40,000 and Mr 42,000 glycoproteins with endo-beta-N- acetylglucosaminidase H also yields a single polypeptide component at Mr 37,000. However, over a 3-h period beginning at 10 min posttranslation, a Mr 39,000 major component and a Mr 41,000 minor component gradually appear in the endo-beta-N-acetylglucosaminidase H digests as the Mr 37,000 component gradually disappears. Analysis of tryptic glycopeptides derived from the Mr 40,000 and 42,000 components suggests that the two components differ by the addition of one extra oligosaccharide to the Mr 42,000 component. Nonequilibrium pH gradient electrophoresis/sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of KS1/4 immunoprecipitates resolves each of the two components into multiple spots. Digestion of the KS1/4 immunoprecipitates with neuraminidase prior to two-dimensional analysis or immunoprecipitation of short pulse-labeled extracts reduces the number of spots to three each at the Mr 40,000 and Mr 42,000 positions. Digestion of the KS1/4 immunoprecipitates with peptide:N-glycosidase F, immunoprecipitation of extracts labeled in the presence of tunicamycin, or endo-beta-N-acetylglucosaminidase H digestion of immunoprecipitates of short pulse-labeled extracts prior to two-dimensional analysis results in a single series of Mr 37,000 spots, suggesting that the polypeptide portions of the Mr 40,000 and Mr 42,000 components may be identical. Endo-beta-N-acetylglucosaminidase H digestion of KS1/4 immunoprecipitates of short pulse-labeled extracts, followed by nonequilibrium pH gradient electrophoresis, V8 protease digestion, and polyacrylamide gel electrophoresis revealed an apparently identical set of polypeptides derived from each of the three Mr 37,000 spots, suggesting that the three spots derive from highly similar polypeptides.

Adenocarcinoma↗
PubMed1990

Enhancement of antibody-dependent cytotoxicity with a chimeric anti-GD2 antibody.

A mouse/human chimeric antibody (ch14.18) was developed that reacts with the disialoganglioside GD2 on the surface of tumor cells of neuroectodermal origin. ch14.18 has the constant regions of a human IgG1 antibody and was expressed in a murine hybridoma. This antibody was produced in tissue culture at concentrations up to 180 mg/liter of spent culture fluid. ch14.18 was characterized and compared to 14.G2a, a murine mAb against GD2 of IgG2a isotype derived from the same parental hybridoma as ch14.18. Scatchard plot analysis of data from saturation binding studies on M21 melanoma cells showed identical binding for ch14.18 and 14.G2a. Indirect immunofluorescence revealed the same staining pattern for ch14.18 and 14.G2a on different melanoma cell lines. Both antibodies were equally capable of targeting M21 xenografts in athymic nude mice. ch14.18- and 14.G2a-activated human C-mediated cytolysis of melanoma cell; however, ch14.18-mediated antibody-dependent cytotoxicity of human effector cells against melanoma cells 50- to 100-fold more efficiently than 14.G2a.

Animals↗
PubMed1990

Serum half-life and tumor localization of a chimeric antibody deleted of the CH2 domain and directed against the disialoganglioside GD2.

Recombinant techniques allow one to engineer an antibody molecule and, in this way, manipulate its properties and functions. We engineered a chimeric human/mouse antibody to the tumor-associated antigen ganglioside GD2, with the aim of decreasing its serum half-life, maintaining its full antigen-binding capacity, and deleting its effector functions, thus making it a potentially useful reagent for the radioimaging of tumors. To this end, the constant region of the human gamma 1 chain was mutated by deleting the second domain (CH2). Here we show that the CH2-deleted antibody (ch14.18-delta CH2) was cleared from the blood of athymic (nu/nu) mice bearing human melanoma tumors with the same kinetics as human IgG F(ab')2. At a beta t1/2 of 12 hr, 0.9% of the injected dose of 125I-labeled ch14.18-delta CH2 was found per milliliter of blood 24 hr after i.v. injection. In biodistribution experiments, 125I-labeled ch14.18-delta CH2 targeted specifically to melanoma xenografts, achieving optimal tumor-to-tissue ratios 12-16 hr after i.v. injection. ch14.18-delta CH2 was localized to the melanoma tumors more rapidly and with better localization ratios than the intact chimeric antibody ch14.18. Sixteen hours after i.v. injection, the tumor-to-blood and tumor-to-liver ratios of ch14.18-delta CH2 were 5 and 12, respectively, while optimal localization ratios obtained for ch14.18 were 1 and 5, respectively, but 96 hr after injection. A reagent such as ch14.18-delta CH2 should be useful for radioimmunodetection of human tumors because of reduced immunogenicity, increased targeting specificity, and rapid clearance from circulation.

Animals↗