lewis-y-antigen and Neoplasms

Monoclonal antibodies represent the most successful class of biopharmaceuticals for the treatment of cancer. Mechanisms of action of therapeutic antibodies are very diverse and reflect their ability to engage in antibody-dependent effector mechanisms, internalize to deliver cytotoxic payloads, and display direct effects on cells by lysis or by modulating the biological pathways of their target antigens. Importantly, one of the universal changes in cancer is glycosylation and carbohydrate-binding antibodies can be produced to selectively recognize tumor cells over normal tissues. A promising group of cell surface antibody targets consists of carbohydrates presented as glycolipids or glycoproteins. In this review, we outline the basic principles of antibody-based targeting of carbohydrate antigens in cancer. We also present a detailed structural view of antibody recognition and the conformational properties of a series of related tissue-blood group (Lewis) carbohydrates that are being pursued as potential targets of cancer immunotherapy.

Topics: Antibodies; Carbohydrate Conformation; Carbohydrate Sequence; Carbohydrates; Epitopes; Humans; Immunotherapy; Lewis Blood Group Antigens; Molecular Sequence Data; Neoplasms

Topics: Animals; Antibiotics, Antineoplastic; Antibodies, Monoclonal; Antigens, Neoplasm; Carcinoma; Clinical Trials, Phase I as Topic; Colonic Neoplasms; Daunorubicin; Digestive System; Doxorubicin; Drug Design; Gastrointestinal Diseases; Humans; Immunotoxins; Lewis Blood Group Antigens; Mice; Mice, Nude; Neoplasms; Neoplasms, Experimental; Organ Specificity; Rats; Rats, Inbred BN; Rats, Nude; Treatment Failure; Xenograft Model Antitumor Assays

We report a first-in-man trial of a humanized antibody (hu3S193) against the Le(y) antigen.. Patients with advanced Le(y)-positive cancers received four infusions of hu3S193 at weekly intervals, with four dose levels (5, 10, 20, and 40 mg/m(2)). The first infusion of hu3S193 was trace labeled with Indium-111, and biodistribution, pharmacokinetics, tumor uptake, and immune response were evaluated in all patients.. A total of 15 patients (7 male/8 female; age range, 42-76 years; 6 breast, 8 colorectal cancer, and 1 non-small-cell lung cancer) were entered into the study. Transient grade 1 to 2 nausea and vomiting was observed following infusion of hu3S193 at the 40 mg/m(2) dose level only. There was one episode of dose-limiting toxicity with self-limiting Common Toxicity Criteria grade 3 elevated alkaline phosphatase observed in one patient with extensive liver metastases. The biodistribution of (111)In-hu3S193 showed no evidence of any consistent normal tissue uptake, and (111)In-hu3S193 uptake was observed in cutaneous, lymph node, and hepatic metastases. Hu3S193 displayed a long serum half-life (T(1/2)beta = 189.63 +/- 62.17 h). Clinical responses consisted of 4 patients with stable disease and 11 patients with progressive disease, although one patient experienced a 89% decrease in a lymph node mass, and one patient experienced inflammatory symptoms in cutaneous metastases, suggestive of a biological effect of hu3S193. No immune responses (human anti-human antibody) to hu3S193 were observed.. Hu3S193 is well tolerated and selectively targets tumors, and the long half-life and biological function in vivo of this antibody makes it an attractive potential therapy for patients with Le(y)-expressing cancers.

Topics: Adult; Aged; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Female; Humans; Immunotherapy; Indium Radioisotopes; Lewis Blood Group Antigens; Male; Middle Aged; Neoplasms; Skin Neoplasms; Time Factors; Tissue Distribution; Treatment Outcome

Rituximab, a humanized monoclonal antibody directed to the CD20 antigen present on B lymphocytes, could potentially abrogate the humoral immune response to murine monoclonal antibodies or immunotoxins by depleting antibody-producing B cells.. A Phase II study of LMB-1, an immunotoxin targeting the Lewis Y tumor antigen, in combination with rituximab was conducted to test the hypothesis that rituximab could abolish or diminish the development of human antibodies to LMB-1. Five patients were treated in this study and received 375 mg/m(2) rituximab on days 1 and 7 followed by 45 micro g/kg/day LMB-1 on days 10, 12, and 14. The development of human antibodies against LMB-1 was detected using a serum neutralization and ELISA.. All five of the patients had a total suppression of circulating CD20/CD19 B-cell population before the administration of the first dose of the immunotoxin. Before rituximab treatment, the mean percentage of CD20/CD19-positive B cells in the five treated patients was 19.8% (range, 4.5-29.8%) of the total peripheral lymphocytes. After two doses of rituximab, CD20/CD19-positive B lymphocytes constituted

Topics: Adult; Aged; Antibodies, Monoclonal; Antibodies, Monoclonal, Murine-Derived; Antibodies, Neoplasm; Antibody Formation; Antigens, CD19; Antigens, CD20; B-Lymphocytes; Female; Humans; Immunotoxins; Lewis Blood Group Antigens; Lymphocyte Depletion; Male; Middle Aged; Neoplasms; Pseudomonas; Rituximab

Our purpose in the study was to establish the maximum tolerated dose and toxicity profile of SGN-10 (or BR96 sFv-PE40), a single-chain immunotoxin. SGN-10 is composed of the fused gene products encoding the translocating and ADP-ribosylating domains of Pseudomonas exotoxin (PE40) and the variable heavy (V(H)) and variable light (V(L)) regions of BR96 monoclonal antibody. This antibody is specific for a Lewis(Y) (Le(Y))-related carbohydrate antigen expressed on multiple carcinomas.. A total of 46 patients with Le(Y)-positive metastatic carcinoma were enrolled in a Phase I dose-escalation study in cohorts of three to six patients who received SGN-10 at doses ranging from 0.024 to 0.962 mg/m(2), administered on days 1, 4, 8, and 11, followed by 2 weeks of rest and a second cycle of therapy. Pharmacokinetics and human antibody response to SGN-10 were also determined.. The maximum tolerated dose of SGN-10 was 0.641 mg/m(2) with gastrointestinal dose-limiting toxicity. Pharmacokinetic studies performed in eight patients at the 0.641-mg/m(2) dose revealed a t([1/2]) of 2.5 +/- 0.3 h and a C(max) of 389 +/- 112 ng/ml. Pharmacodynamic analyses demonstrated a rapid clearance of the drug by day 11 associated with an antitoxin human antitoxin antibody (HATA) response in most patients. Signs consistent with a modest vascular leak syndrome, specifically, transient hypoalbuminemia, were observed in patients treated with doses of > or =0.384 mg/m(2). No complete or partial tumor responses were observed at an 8-week evaluation, although 31% of patients had stable disease.. The maximal tolerated dose of SGN-10 given twice weekly for 2 weeks is 0.641 mg/m(2) with gastrointestinal dose-limiting toxicity. The immunogenicity of the toxin moiety limits the ability of SGN-10 to circulate by day 11 of therapy. Studies are ongoing to evaluate strategies to ameliorate toxicities and to inhibit the development of the anti-SGN-10 immune response.

Topics: Adult; Aged; Antibodies, Monoclonal; Cohort Studies; Female; Humans; Immunotoxins; Lewis Blood Group Antigens; Male; Maximum Tolerated Dose; Middle Aged; Neoplasms; Recombinant Fusion Proteins; Treatment Outcome

B3 is a murine monoclonal antibody (mAb) that recognizes a LewisY carbohydrate antigen present on the surface of many carcinomas. An imaging and Phase I trial was performed to study the ability of 111In-mAb B3 to image known metastasis and determine the maximum tolerated dose (MTD), dose-limiting toxicity (DLT), kinetics, and biodistribution of 90Y-mAb B3. Patients (n = 26) with advanced epithelial tumors that express the LewisY antigen were entered. All patients received 5 mCi of 111In-mAb B3 for imaging. 90Y-mAb B3 doses were escalated from 5 to 25 mCi in 5-mCi increments. 111In-mAb B3 and 90Y-mAb B3 were coadministered over a 1-h infusion. Definite tumor imaging was observed in 20 of 26 patients. Sites imaged included lung, liver, bone, and soft tissues. The MTD of 90Y-mAb B3 was determined to be 20 mCi. The DLTs were neutropenia and thrombocytopenia. Tumor doses ranged from 7.7 to 65.1 rad/mCi. 111In- and 90Y-mAb B3 serum pharmacokinetics (n = 23) were found to be similar. The amount of B3 administered (5, 10, and 50 mg) did not alter the pharmacokinetics. Bone marrow biopsies (n = 23) showed 0.0038+/-0.0016% of injected dose/gram for 111In-mAb B3 compared to 0.0046+/-0.0017% of injected dose/gram for 90Y-mAb B3 (P = 0.009). When given to patients with carcinomas that express the LewisY antigen, 111In-mAb B3 demonstrated good tumor localization. The MTD of 90Y-mAb B3 is 20 mCi, with myelosuppression as the DLT. Higher doses of radioactivity need to be delivered to achieve an antitumor effect. Humanized mAb B3 is being developed for evaluation in radioimmunotherapy. A clinical trial to explore the use of higher doses of 90Y-mAb B3 with autologous stem cell support is planned.

Topics: Adult; Aged; Animals; Antibodies, Monoclonal; Area Under Curve; Female; Hematologic Diseases; Humans; Indium Radioisotopes; Lewis Blood Group Antigens; Male; Metabolic Clearance Rate; Mice; Middle Aged; Neoplasms; Radionuclide Imaging; Tissue Distribution; Treatment Outcome; Yttrium Radioisotopes

Immunotoxin LMB-1 is composed of monoclonal antibody B3 chemically linked to PE38, a genetically engineered form of Pseudomonas exotoxin. B3 recognizes a carbohydrate antigen (Le(Y)) present on many human solid tumors. LMB-1 has excellent antitumor activity in nude mice bearing Le(Y)-positive tumors. We conducted a phase I study of 38 patients with solid tumors who failed conventional therapy and whose tumors expressed the Le(Y) antigen. Objective antitumor activity was observed in 5 patients, 18 had stable disease, 15 progressed. A complete remission was observed in a patient with metastatic breast cancer to supraclavicular nodes. A greater than 75% tumor reduction and resolution of all clinical symptoms lasting for more than six months was observed in a colon cancer patient with extensive retroperitoneal and cervical metastasis. Three patients (two colon, one breast cancer) had minor responses. The maximum tolerated dose of LMB-1 is 75 microgram/kg given intravenously three times every other day. The major toxicity is vascular leak syndrome manifested by hypoalbuminemia, fluid retention, hypotension and, in one case, pulmonary edema. Although immunotoxins have been evaluated in clinical studies for more than two decades, this is the first report of antitumor activity in epithelial tumors.

Topics: Adult; Aged; Animals; Antibodies, Monoclonal; Drug Tolerance; Exotoxins; Female; Humans; Immunotoxins; Lewis Blood Group Antigens; Male; Mice; Middle Aged; Neoplasms; Tomography, X-Ray Computed; Vascular Diseases

Cell surface carbohydrates of the Lewis blood group antigens, Lewis X (Le

Topics: Anthracenes; Antigens, Tumor-Associated, Carbohydrate; Boronic Acids; Cell Line, Tumor; Fluorescent Dyes; Humans; Lewis Blood Group Antigens; Microscopy, Fluorescence; Neoplasms; Oligosaccharides; Sialyl Lewis X Antigen; Triazoles

Lewis Y (LeY) antigen is an oligosaccharide that is highly expressed at the cell surface in various human cancers. Increased LeY expression activates epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2) and promotes cell proliferation in EGFR-overexpressing cells. However, the effect of downregulation of LeY expression on cell proliferation in HER2-overexpressing cells remains unknown. FUT1 encodes α1,2-fucosyltransferase, a key enzyme for LeY synthesis. We knocked down FUT1 by short interfering RNA (siRNA) in four HER2-overexpressing human cancer cell lines, including NCI-N87, MKN7, SKBr3 and BT474. We investigated whether downregulation of LeY and alteration in the glycosylation status of these cells affect cell proliferation and HER2 activation. Knocking down FUT1 expression markedly inhibited proliferation of NCI-N87, which highly expressed EGFR and was sensitive to EGFR deprivation. Furthermore, FUT1 siRNA downregulated the total amount of HER2 protein, phosphorylation of HER2 and EGFR, and phosphorylation of extracellular signal-regulated kinase (ERK) in this cell line. Moreover, the marked downregulation of phosphorylation of HER2 and ERK was observed following short-time EGF-stimulation. These effects were not observed in the other three cell lines. Our results suggest that knockdown of FUT1 downregulates HER2 signaling via EGFR downregulation. FUT1 may serve as a new molecular target for HER2-overexpressing human cancers with activated EGFR signaling.

Topics: Apoptosis; Blotting, Western; Cell Cycle; Cell Proliferation; Down-Regulation; Epidermal Growth Factor; ErbB Receptors; Fucosyltransferases; Galactoside 2-alpha-L-fucosyltransferase; Humans; Lewis Blood Group Antigens; National Cancer Institute (U.S.); Neoplasms; Phosphorylation; Real-Time Polymerase Chain Reaction; Receptor, ErbB-2; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; RNA, Small Interfering; Signal Transduction; Tumor Cells, Cultured; United States

In this study we aimed to determine the suitability of the Lewis-Y carbohydrate antigen as a target for immunotherapy using genetically redirected T cells. Using the 3S193 monoclonal antibody and immunohistochemistry, Lewis-Y was found to be expressed on a range of tumors including 42% squamous cell lung carcinoma, 80% lung adenocarcinoma, 25% ovarian carcinoma, and 25% colorectal adenocarcinoma. Expression levels varied from low to intense on between 1% and 90% of tumor cells. Lewis- was also found in soluble form in sera from both normal donors and cancer patients using a newly developed enzyme-linked immunosorbent assay. Serum levels in patients was often less than 1 ng/mL, similar to normal donors, but approximately 30% of patients had soluble Lewis-Y levels exceeding 1 ng/mL and up to 9 ng/mL. Lewis-Y-specific human T cells were generated by genetic modification with a chimeric receptor encoding a single-chain humanized antibody linked to the T-cell signaling molecules, T-cell receptor-zeta, and CD28. T cells responded against the Lewis-Y antigen by cytokine secretion and cytolysis in response to tumor cells. Importantly, the T-cell response was not inhibited by patient serum containing soluble Lewis-Y. This study demonstrates that Lewis-Y is expressed on a large number of tumors and Lewis-Y-specific T cells can retain antitumor function in the presence of patient serum, indicating that this antigen is a suitable target for this form of therapy.

Topics: Antigens, Neoplasm; Cell Line, Tumor; Cytotoxicity, Immunologic; Humans; Immunotherapy, Adoptive; Interferon-gamma; Lewis Blood Group Antigens; Neoplasms; Receptors, Antigen, T-Cell; T-Lymphocytes; Transduction, Genetic

The use of single-chain variable fragment (scFv) constructs has been investigated in cancer radioimmunotherapy (RIT) and radioimmunodetection, as these molecules permit rapid tumor penetration and clearance from the serum relative to whole IgG. Multimerization of scFv constructs has demonstrated improvements in functional affinity (i.e., avidity) and maximal tumor uptake. In this paper, we report the first biodistribution and pharmacokinetics studies of a noncovalent, direct-linked scFv (V(L)-0-V(H)) trimeric/tetrameric "multimer" of the anti-Lewis Y monoclonal antibody, hu3S193. The in vitro binding and in vivo biodistribution of the hu3S193 multimer was characterized alongside the hu3S193 F(ab')(2) following radiolabeling with the Indium-111 ((111)In) radioisotope. Immunoreactivities of the radiolabeled multimer and F(ab')(2) were 73% and 53.2%, and binding affinities (K(a)) were 1.58 x 10(7) M(1) and 4.31 x 10(6) M (1) for the multimer and F(ab')(2), respectively. Maximal tumor uptake in Le(y)-positive MCF-7 breast cancer xenografted BALB/c nude mice was 12.6 +/- 2.5 percent injected dose/per gram (%ID/g) at 6 hours postinjection for the multimer and 15.7 +/- 2.1 %ID/g at 24 hours postinjection for the F(ab')(2). However, limited in vitro stability and high renal localization of radiolabeled constructs were observed, which, despite the observed tumor targeting of the hu3S193 multimer, most likely preclude its use in RIT and imaging modalities.

Topics: Animals; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Area Under Curve; Cell Line, Tumor; Chromatography, Gel; Drug Stability; Female; Humans; Immunoconjugates; Immunoglobulin Fab Fragments; Immunoglobulin Variable Region; Indium Radioisotopes; Lewis Blood Group Antigens; Mammary Neoplasms, Experimental; Mice; Mice, Inbred BALB C; Mice, Nude; Neoplasms; Radionuclide Imaging; Recombinant Proteins; Tissue Distribution; Transplantation, Heterologous

Lewis Y (LeY) antigen is highly expressed in a variety of human carcinomas of epithelial cell origin. Recent studies suggest functional blockade of LeY may provide a novel therapeutic approach for the treatment of cancers. However, suppressing LeY expression by genetic manipulation and its impact on neoplastic cell proliferation has not been investigated. We report here that different fucosyltransferases (FUTs) were expressed with the greatest expression of fucosyltransferase I or IV (FUT1/4), the two key enzymes for the synthesis of LeY in human epidermoid carcinoma A431 cells. Knocking down FUT1/4 expression by short interfering RNA technique dramatically reduced the expression of FUT1/4 and LeY and inhibited cell proliferation through decreasing epidermal growth factor receptor (EGFR) signaling pathway. Treatment of A431 cells that were inoculated into the nude mice with FUT1 siRNA or FUT4 siRNA greatly impeded tumor growth. Suppressing FUT1/4 expression also blocked EGF-induced tyrosine phosphorylation of EGFR and mitogen-activated protein kinases. In conclusion, suppressing the expression of FUT1/4 by RNAi technology reduces the synthesis of LeY and inhibits cancer growth. It may serve as a potential methodology for the treatment of cancers that express LeY glycoconjugates.

Topics: Animals; Cell Line, Tumor; Cell Proliferation; Epidermal Growth Factor; ErbB Receptors; Fucosyltransferases; Galactoside 2-alpha-L-fucosyltransferase; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Humans; Lewis Blood Group Antigens; Lewis X Antigen; MAP Kinase Signaling System; Mice; Mice, Nude; Mitogen-Activated Protein Kinases; Neoplasms; Phosphotyrosine; RNA, Small Interfering; Transfection; Xenograft Model Antitumor Assays

During the initiation of tumor associated angiogenesis endothelial cells migrate, adhere to extracellular matrix and form cell-cell contacts. Humoral factors of malignant cells conduct this process. We investigated whether cell surface expression of the carbohydrate blood group determinant Lewis(y) (CD174) and its precursor structure H2 (CD173) on endothelial cells is influenced by soluble factors of tumor cells. Using a bone marrow derived endothelial cell line we observed an enhanced expression of CD173/CD174 and transcription of FUT1, the key enzyme for their synthesis, after treatment with tumor necrosis factor-alpha (TNF-alpha) or conditioned supernatants of the leukemia cell line KG1a. CD173/CD174 are concentrated on pseudopodial extensions responsible for initial contacts between endothelial cells. Endothelial migration induced by TNF-alpha could be diminished by antibodies to CD174 as well as by siRNA induced downmodulation of FUT1 transcription. Endothelial FUT1-siRNA-transfectants displayed impaired in vitro angiogenesis when cultivated on extracellular matrix and in spheroid assays. In vivo upregulation of CD174 expression was observed immunocytologically in capillaries of tumor-infiltrated tissue. Together, our observations point to a tumor induced transcription of endothelial FUT1 and consequently an enhanced expression of CD174 which is involved in migration and early cell-cell contacts during tumor associated angiogenesis.

Topics: Antibodies; Capillaries; Carbohydrate Epimerases; Cell Adhesion; Cell Communication; Cell Movement; Collagen; Drug Combinations; Endothelial Cells; Extracellular Matrix; Flow Cytometry; Fucosyltransferases; Galactoside 2-alpha-L-fucosyltransferase; HL-60 Cells; Humans; Laminin; Lewis Blood Group Antigens; Neoplasms; Neovascularization, Pathologic; Protein Precursors; Proteoglycans; RNA, Small Interfering; Spheroids, Cellular; Subcellular Fractions; Tumor Necrosis Factor-alpha; Up-Regulation

Although current demands for therapeutic mAbs are growing quickly, production methods to date, including in vitro mammalian tissue culture and transgenic animals, provide only limited quantities at high cost. Several tumor-associated antigens in tumor cells have been identified as targets for therapeutic mAbs. Here we describe the production of mAb BR55-2 (IgG2a) in transgenic plants that recognizes the nonprotein tumor-associated antigen Lewis Y oligosaccharide overexpressed in human carcinomas, particularly breast and colorectal cancers. Heavy and light chains of mAb BR55-2 were expressed separately and assembled in plant cells of low-alkaloid tobacco transgenic plants (Nicotiana tabacum cv. LAMD609). Expression levels of plant-derived mAb (mAbP) were high (30 mg/kg of fresh leaves) in T1 generation plants. Like the mammalian-derived mAbM, the plant mAbP bound specifically to both SK-BR3 breast cancer cells and SW948 colorectal cancer cells. The Fc domain of both mAbP and mAbM showed the similar binding to FcgammaRI receptor (CD64). Comparable levels of cytotoxicity against SK-BR3 cells were also shown for both mAbs in antibody-dependent cell-mediated cytotoxicity assay. Furthermore, plant-derived BR55-2 efficiently inhibited SW948 tumor growth xenografted in nude mice. Altogether, these findings suggest that mAbP originating from low-alkaloid tobacco exhibit biological activities suitable for efficient immunotherapy.

Topics: 3T3 Cells; Animals; Antibodies, Monoclonal; Antibody Specificity; Antibody-Dependent Cell Cytotoxicity; Flow Cytometry; Gene Expression; Humans; Immunoglobulin Fc Fragments; Immunotherapy; Lewis Blood Group Antigens; Mice; Mice, Inbred BALB C; Mice, Nude; Neoplasms; Nicotiana; Plantibodies; Plants, Genetically Modified; Receptors, IgG; Tumor Cells, Cultured

The aim of the present study was to produce glycosylation variants of the therapeutic Lewis Y-specific humanized IgG1 antibody IGN311 to enhance cell-killing effector function. This was achieved via genetic engineering of the glycosylation machinery of the antibody-producing host. Antibody genes were transiently cotransfected with acetyl-glycosaminyltransferase-III genes into human embryonic kidney-EBV nuclear antigen cells. A control wild-type antibody, IGN311wt, was expressed in the same host using identical expression vectors, but without cotransfection of genes for acetyl-glycosaminyltransferase-III expression. Both expression products were purified to homogeneity and characterized. The glyco-engineered expression product (IGN312-Glyco-I) showed a remarkably homogenous N-linked glycosylation pattern consisting of one major hybrid-type, non-fucosylated and agalactosylated form carrying a bisecting GlcNAc-group. Wild-type expression product (IGN311wt) on the other hand was glycosylated by a multitude of different core-fucosylated complex-type structures of variable degrees of galactosylation. Target affinity of the glyco-engineered antibody as well as heavy and light chain assembly were not affected by acetyl-glycosaminyltransferase-III expression. In vitro experiments showed a approximately 10-fold increase of antibody-dependent cellular cytotoxicity of the glyco-engineered antibody using different Lewis Y-positive target cancer cell lines (SK-BR-3, SK-BR-5, OVCAR-3, and Kato-III). Complement-mediated cytotoxicity of IGN312-Glyco-I was 0.4-fold reduced using SK-BR-5 as target cell line. The reduction of complement activation could be prevented and even converted into a slight increase of activity by using a different molecular-biological approach directing the glycosylation towards increased levels of complex N-linked oligosaccharides of bisected, non-fucosylated type, as a result of cotransfection of mannosidase II together with acetyl-glycosaminyltransferase-III.

Topics: Antibodies, Monoclonal; Antibody Specificity; Antibody-Dependent Cell Cytotoxicity; Cell Line, Tumor; Glycosylation; Humans; Immunoglobulin G; Lewis Blood Group Antigens; Mannosidases; N-Acetylglucosaminyltransferases; Neoplasms; Oligosaccharides; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Transfection

In this study, human T cells were provided with a reactivity against the Lewis-Y (Le(Y)) carbohydrate antigen, which is overexpressed on 70% of epithelial-derived tumors, but not normally recognized by T cells. Antitumor reactivity was achieved by transduction of T cells with a gene encoding a cell-surface chimeric receptor composed of single-chain anti-Le(Y) antibody linked to an enhanced cytoplasmic signaling domain made up of CD28 and CD3-zeta. Importantly, the single-chain antibody was humanized to try to reduce potential problems of human anti-mouse antibody responses in patients receiving chimeric receptor-modified T cells in future clinical trials. T cells expressing the chimeric receptor were demonstrated to secrete cytokines and proliferate in response to receptor ligation and lysed Le(Y+) tumors in vitro. Another aspect of this study was the finding that no activity was observed against normal tissue, as represented by autologous neutrophils that express low levels of Le(Y). Significantly, systemic delivery of anti-Le(Y) T cells dramatically inhibited established s.c. human ovarian OVCAR-3 tumors (a recognized difficult model to treat) in mice. Finally, we demonstrated that anti-Le(Y) T cells preferentially expanded or accumulated in the tumor compared with control empty vector T cells, thereby providing mechanistic insight into the specific antitumor response. This study supports the use of humanized gene-modified T cells as a potential therapy for Le(Y+) malignancies.

Topics: Adoptive Transfer; Animals; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Autoimmunity; CD28 Antigens; Cell Line, Tumor; Cell Membrane; Cell Proliferation; Clinical Trials as Topic; Cytokines; Flow Cytometry; Genetic Vectors; Humans; Immunohistochemistry; Immunotherapy; Leukocytes, Mononuclear; Lewis Blood Group Antigens; Mice; Neoplasm Transplantation; Neoplasms; Neutrophils; Receptors, Antigen, T-Cell; Recombinant Fusion Proteins; Retroviridae; Sialic Acid Binding Ig-like Lectin 3; T-Lymphocytes; Time Factors

Topics: Animals; Antibodies, Monoclonal; Antibodies, Monoclonal, Murine-Derived; Antibodies, Neoplasm; Antibody Formation; Antigens, CD19; Antigens, CD20; Humans; Immunotoxins; Lewis Blood Group Antigens; Neoplasms; Rituximab

A Lewis(y) (Le(y)) tetrasaccharide modified by an artificial aminopropyl spacer was synthesized by a highly convergent approach that employed a levulinoyl ester and a 9-fluorenylmethoxycarbonate for temporary protection of the hydroxy groups and a trichloroethyloxycarbonyl as an amino protecting group. The artificial aminopropyl moiety was modified by a thioacetyl group, which allowed efficient conjugation to keyhole limpet hemocyanin (KLH) modified by electrophilic 4-(maleimidomethyl)cyclohexane-1-carboxylate (MI). Mice were immunized with the KLH-MI-Le(y) antigen. A detailed analysis of sera by ELISA established that a strong immunoglobulin G (IgG) antibody response was elicited against the linker region. The use of a smaller and more flexible 3-(bromoacetamido)propionate for the attachment of Le(y) to KLH not only reduced the IgG antibody response against the linker but also led to a significantly improved immune response against the Le(y) antigen. This study shows that highly antigenic linkers suppress antibody responses to weak antigens such as self-antigens.

Topics: Antibodies; Carbohydrate Conformation; Carrier Proteins; Cross-Linking Reagents; Enzyme-Linked Immunosorbent Assay; Hydrolysis; Immunization; Immunogenetics; Lewis Blood Group Antigens; Maleimides; Neoplasms; Polysaccharides; Protein Binding

Stimulation of monocytes by interaction of monoclonal antibodies (mAbs) with Fc gamma receptors (FcgammaRs) results in the activation of various monocyte effector functions. In the present investigation we show that the anti-Lewis Y (LeY) anti-tumour mAb ABL 364 and its mouse/human IgG1 chimaera induce both antibody-dependent cellular cytotoxicity (ADCC) and the release of tumour necrosis factor alpha (TNF-alpha) during mixed culture of monocytes with LeY+ SKBR5 breast cancer cells in vitro. Although anti-LeY mAb-mediated TNF-alpha release paralleled ADCC activity, cytokine release required a higher concentration of sensitizing mAb than the induction of cytolysis. The determination of the FcgammaR classes involved in the induction of the distinct effector functions showed that anti-LeY mAb-induced cytolysis was triggered by interaction between anti-LeY mAbs and FcgammaRI. In contrast, mAb-induced TNF-alpha release mainly depended on the activation of monocyte FcgammaRII. Neutralization of TNF-alpha showed no influence on monocyte ADCC activity towards SKBR5 target cells. Our data indicate an independent regulation of anti-LeY mAb induced effector functions of ADCC and TNF-alpha release which seemed to be triggered by activation of different types of FcgammaR.

Topics: Animals; Antibodies, Monoclonal; Antibody-Dependent Cell Cytotoxicity; Chimera; Humans; Immunoglobulin G; Lewis Blood Group Antigens; Lymphocyte Activation; Mice; Monocytes; Neoplasms; Receptors, IgG; Tumor Cells, Cultured; Tumor Necrosis Factor-alpha

In this study we show by immunoblotting that B1 and B3, two newly isolated monoclonal antibodies, react with a variety of glycoproteins with different molecular weights expressed in stomach, pancreas, colorectal and breast cancers. The pattern of reactivity differed among cancers arising in different tissues, although no correlation has been observed with the histopathological characteristics of the lesion analysed. MAb B3 and MAb B1, have a limited reactivity with peritumoral tissues, whereas react very strongly with metastatic lesion. Because of the limited reactivity of these antibodies with normal tissue, MAbs B3 and B1, armed with toxin in the form of recombinant immunotoxins, can be useful in treating certain kinds of cancer such as metastatic lesions. However, until current clinical trials are completed, we will not know if they will be helpful in cancer treatment.

Topics: Antibodies, Monoclonal; Glycoproteins; Humans; Immunoblotting; Immunotoxins; Lewis Blood Group Antigens; Neoplasms

The Lewis Y (Ley) antigen is a blood group-related antigen that is expressed in a high proportion of epithelial cancers (including breast, colon, ovary, and lung cancer) and is an attractive target for monoclonal antibody-directed therapy. The murine monoclonal 3S193 (IgG3) was generated in BALB/c mice by immunization with Ley-expressing cells of the MCF-7 breast carcinoma cell-line. The murine 3S193 showed high specificity for Ley in ELISA tests with synthetic Ley and Ley-containing glycoproteins and glycolipids and also reacted strongly in rosetting assays and cytotoxic tests with Ley-expressing cells. We generated a humanized form of the murine 3S193 antibody by linking cDNA sequences encoding the variable region of murine 3S913 with frameworks of the human KOL heavy chain and REI K chain. The genes for the humanized 3S193 monoclonal antibody IgG1 were transfected into mouse myeloma NS0 cells and cloned for the establishment of high antibody-producing colonies. Humanized 3S193 antibody was subsequently produced through in vitro culture and under good manufacturing practice conditions using hollow-fiber bioreactors. The purified humanized 3S193 (hu3S193) was subsequently characterized and validated for use in preliminary immunotherapy investigations. hu3S193 reacted specifically with Ley antigen, with similar avidity to the murine form. hu3S193 demonstrated potent immune effector function, with higher antibody-dependent cell-mediated cytotoxicity than its murine counterpart and potent complement-dependent cytotoxicity (ED50, 1.0 microg/ml). The in vivo immunotherapeutic potential of hu3S193 was assessed in a human breast xenograft model using MCF-7, Ley-positive cells. Six i.v. doses of up to 1 mg of hu3S193 were administered to animals bearing established tumors (120-130 mm3) with no significant effect on tumor growth. In contrast, in an MCF-7 xenograft preventive model, a 1-mg hu3S193 dosage schedule was able to significantly slow tumor growth compared with placebo and isotype-matched control IgG1 antibody. hu3S193 has promise for immunotherapy of Ley-positive tumors and is currently entering Phase I clinical trials.

Topics: Amino Acid Sequence; Animals; Antibodies, Monoclonal; Biosensing Techniques; Breast Neoplasms; Cloning, Molecular; DNA, Complementary; Dose-Response Relationship, Immunologic; Enzyme-Linked Immunosorbent Assay; Humans; Hybridomas; Kinetics; Lewis Blood Group Antigens; Mammary Neoplasms, Experimental; Mice; Mice, Inbred BALB C; Molecular Sequence Data; Neoplasm Transplantation; Neoplasms; Sequence Homology, Amino Acid; Time Factors; Tumor Cells, Cultured

We have generated a monoclonal antibody (MAb), FS01, which inhibits the procoagulant activity (CCA-1) produced by a human squamous cell carcinoma cell line, LK52. Expression of the antigen recognized by FS01 MAb in various cancer cell lines correlated well with the procoagulant activities of the expressing cell lines. Our objective was to characterize the molecule reacting with FS01 MAb and to analyze its involvement in the CCA-1 procoagulant activity. The molecule was identified as a glycolipid and found to be involved in the procoagulant activity because both procoagulant activity and reactivity to FS01 MAb were lost after endoglycoceramidase treatment of CCA-1. Furthermore, FS01 MAb recognized the Lewis Y (Le[y]) antigen. To confirm the involvement of a glycolipid incorporating the Le(y) antigen in the procoagulant activity, we attempted to purify CCA-1 from LK52 culture supernatant. In one of the purification steps, a fraction containing low procoagulant activity (CCA-1p) separated from the Le(y)-positive fraction (CCA-1c). Although CCA-1c alone did not show procoagulant activity, the procoagulant activity of CCA-1p was augmented by CCA-1c and this augmentation was inhibited by FS01 MAb. Furthermore, CCA-1c enhanced the procoagulant activity of 33 cell lines tested as well as CCA-1p. In addition, purified Le(y) glycolipid from canine intestine augmented the procoagulant activity of CCA-1p, and this augmentation also could be inhibited by FS01 MAb. We conclude that Le(y) glycolipid is a co-factor for the procoagulant activity derived from cancer cells.

Topics: Animals; Antibodies, Monoclonal; Antigens, Neoplasm; Blood Coagulation Factors; Cells, Cultured; Chlorocebus aethiops; COS Cells; Dogs; Female; Glycolipids; Humans; Immunoblotting; Lewis Blood Group Antigens; Membrane Glycoproteins; Neoplasms; Tumor Cells, Cultured; Vero Cells

Topics: Animals; Antibodies, Bacterial; Antibodies, Neoplasm; Antibody Affinity; Antigens, Bacterial; Binding Sites, Antibody; Carbohydrates; Humans; Immunoglobulin Fab Fragments; Lewis Blood Group Antigens; Mice; Models, Molecular; Molecular Structure; Neoplasms

The crystal structures of the murine BR96 Fab and its human chimera have been determined in complex with the nonoate methyl ester derivative of Lewis Y (nLey) at 2.8 A and 2.5 A resolution, respectively. BR96 binds the carbohydrate in a large pocket which is formed by residues of all CDR loops except L2. The binding of the carbohydrate is mediated predominantly by aromatic residues in BR96. Analysis of the structure suggests that BR96 is capable of recognizing a structure larger than the Le(y) tetrasaccharide, providing a possible explanation for its high tumour selectivity. The structure provides a rationale for mutagenesis experiments that have resulted in BR96 CDR loop mutants with increased affinity for nLey and/or tumour cells.

Topics: Animals; Antibodies, Monoclonal; Antibodies, Neoplasm; Binding Sites, Antibody; Carbohydrate Sequence; Crystallography, X-Ray; Humans; Immunoglobulin Fab Fragments; Lewis Blood Group Antigens; Mice; Models, Molecular; Molecular Sequence Data; Molecular Structure; Mutation; Neoplasms; Protein Conformation; Recombinant Fusion Proteins