Biomedical subjects

N Hanai

Publications and source records attributed to N Hanai.

At least 19 recordsLinked to original sources

PubMed1996

Reversal of adriamycin resistance with chimeric anti-ganglioside GM2 antibody.

Ganglioside GM2 is one of the major cell-surface gangliosides expressed in human tumors. We earlier established a mouse/human IgG1 chimeric anti-GM2 antibody, KM966, which displayed anti-tumor activity in human tumor cells both in vitro and in vivo. In this study, we have screened for changes in ganglioside expressions in several drug-resistant human cancer cell lines to examine the modulation of drug resistance by immunotherapy with anti-ganglioside antibodies. Increased GM2 expression, detected by flow cytometry and thin-layer chromatography, was observed in the SBC-3/ADM and AdrR MCF7 adriamycin-resistant cell lines, in contrast with their parental lines. In other related gangliosides, ganglioside GD2 levels in AdrR MCF7 were higher than those in MCF7 cells. We confirmed increased N-acetylgalactosaminyltransferase mRNA in adriamycin-resistant cell lines, as compared with the parental cells, by Northern-blot analysis. Moreover, to investigate the possibility of exploiting the anti-tumor activity of KM966 in order to overcome resistance to adriamycin, we investigated the antibody-dependent cell-mediated cytotoxity of human peripheral mononuclear blood cells and the complement-dependent cytotoxity of human serum with KM966 against SBC-3, SBC-3/ADM, MCF7 and AdrR MCF7. Significantly higher killing via KM966 was observed in SBC-3/ADM and AdrR MCF7 cells as compared with the parental cells. This suggests that passive immunotherapy using KM966 against human adriamycin-resistant cancer may be useful for overcoming resistance to adriamycin.

Antibiotics, Antineoplastic↗

PubMed1996

Histamine enhanced the TNF-alpha-induced expression of E-selectin and ICAM-1 on vascular endothelial cells.

Cell adhesion molecules are expressed on endothelial cells by various proinflammatory cytokines. Tumor necrosis factor-alpha (TNF-alpha) induces the expression of E-selectin and intercellular adhesion molecule-1 (ICAM-1) on human umbilical vein endothelial cells (HUVEC). Although histamine is a potent vasoactive mediator, it does not induce the expression of E-selectin and ICAM-1. In this report, we show that histamine concentration-dependently enhances the TNF-alpha-induced expression of E-selectin and ICAM-1 on HUVEC. The histamine-enhanced expression of E-selectin and ICAM-1 was inhibited by the histamine H1 receptor antagonists, mepyramine and diphenhydramine. KW-4679 and ketotifen, antiallergic drugs with histamine H1 receptor antagonistic activity, potently inhibit the expression of E-selectin and ICAM-1. A histamine H2 receptor antagonist, ranitidine, did not affect the histamine-induced expression of cell adhesion molecules. These data indicate that histamine induces the expression of E-selectin and ICAM-1 synergistically with TNF-alpha through histamine H1 receptors.

Animals↗

PubMed1996

Characterization of a T cell line specific to an anti-Id antibody related to the carbohydrate antigen, sialyl SSEA-1, and the immundominant T cell antigenic site of the antibody.

The stage-specific embryonic Ag-1 (SSEA-1) is a carbohydrate Ag and regarded as an onco-developmental Ag. Sialyl SSEA-1 Ag, the sialylated form of SSEA-1, is frequently expressed in human cancer cells as well as in murine cancer cells. A mAb, FH-6, was shown to specifically recognize the Ag. We have generated five anti-Id Abs directed to the paratope-related idiotopes of the FH-6 Ab. One of these anti-Id Abs, Id-F2, increased the survival of host mice that were inoculated with Meth-A cells expressing the sialyl SSEA-1 Ag. To clarify the exact mechanism underlying the antitumor effect of the anti-Id Ab, we established a T cell line that recognized Id-F2 in association with MHC class II molecules. The T cell line was CD4+V beta 8+, and produced IL-2, exhibiting helper activity for B cells. The VH CDR2 region of the Id-F2 amino acid sequences turned out to be strongly immunogenic to T cells. When the immune complexes, consisting of the sialyl SSEA-1 Ag, FH-6, and Id-F2, were formed at the Meth-A cell-surface, the T cell line showed a strong proliferative response. The possible roles played by such T cell subsets in the anti-tumor effect are discussed.

Amino Acid Sequence↗

PubMed1996

Transducin-mediated, isoform-specific interaction of recombinant rat nucleoside diphosphate kinases with bleached bovine retinal rod outer segment membranes.

The properties of the binding of recombinant rat nucleoside diphosphate (NDP) kinase isoforms alpha and beta (NDP kinase alpha and beta, respectively) to bleached bovine retinal rod outer segment (ROS) membranes were investigated. It was found that: (1) both NDP kinase isoforms interacted with ROS membranes in a pH-, cation- and GTPgammaS-dependent manner; (2) the retinal G-protein transducin was an obligatory factor for the interaction; (3) the apparent affinity of NDP kinase alpha for ROS membranes was about 100-fold higher than that of NDP kinase beta; and (4) an alpha-isoform-specific peptide, corresponding to the sequence of the N-terminal third (variable region), had the ability to displace bovine NDP kinase from ROS membranes. The results suggest the possible involvement of NDP kinases in cellular regulation via interaction with G-proteins and provide a structural basis for the possible differential roles of mammalian NDP kinase isoforms in the cell.

Amino Acid Sequence↗

PubMed1996

Decreased expression of nucleoside diphosphate kinase alpha isoform, an nm23-H2 gene homolog, is associated with metastatic potential of rat mammary-adenocarcinoma cells.

The nm23 gene [encoding nucleoside diphosphate kinase (NDPK)] may act as a metastasis suppressor in certain tumor cells. We investigated the role of NDPK isoforms (alpha and beta) in the metastatic processes, using rat mammary-adenocarcinoma cell lines of poor (MTC) and high (MTLn3) spontaneous metastatic potential respectively. In these cell lines, as in most rat tissues, the alpha isoform (nm23-H2 homolog) was more highly expressed than the beta isoform (nm23-H1 homolog) at the mRNA and protein levels. When examined by Northern- and Western-blot analyses, expression of the 2 isoforms was reduced in highly metastatic MTLn3 cells compared with poorly metastatic MTC cells. The reduced expression was also associated with diminished NDPK-enzyme activity in the cell extracts. Southern-blot and RT-PCR-SSCP analyses suggested that the 2 genes were not grossly altered or mutated in their translation regions. MTLn3 cell clones transfected with NDPKalpha or NDPKbeta cDNA were all tumorigenic when implanted into the mammary fat pad of syngeneic rats. Among those, only clones transfected with the NDPKalpha gene exhibited reduced lung metastasis in a spontaneous metastasis assay.

Adenocarcinoma↗

PubMed1996

KM195 as an immunohistochemical marker of adenocarcinoma of the lung.

In order to improve the diagnosis of lung carcinoma, in which a complicated histologic pattern is present, the immunohistochemistry of 119 adenocarcinomas, 65 squamous cell carcinomas, 12 small cell carcinomas, 18 large cell carcinomas, and 15 metastatic adenocarcinoma in the lung were evaluated using a monoclonal antibody, KM195, against lung carcinoma, and compared with the immunohistochemical results using anti-human cytokeratin (CAM 5.2) and other monoclonal antibodies. Formalin-fixed, paraffin-embedded tissues were stained using the labeled streptavidin-biotin method. Extracts from fresh tissue homogenate, after fractionation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, were transferred by Western blotting and stained with KM195. The anti-lung adenocarcinoma, murine, monoclonal antibody KM195 (IgG), was positive in 107 of 119 adenocarcinomas (90%), in 15 of 18 large cell carcinoma (83%), in three of 65 squamous cell carcinomas (5%), 13 of 15 (87%) metastatic adenocarcinoma in the lung, and was negative in 12 small cell carcinomas (P < 0.001). KM195-bound protein of primary and metastatic adenocarcinoma in the lung cases concentrated at about 40 kDa. In contrast, CAM 5.2 was positive in 52 of 67 (78%) adenocarcinomas, 10 of 62 (16%) squamous cell carcinomas, and was negative in six small cell carcinomas. These results suggest that the immunohistochemistry for KM195 may be a more useful marker over CAM 5.2 for the diagnosis of pulmonary adenocarcinoma.

Adenocarcinoma↗

PubMed1996

Dramatically different phenotypes in mouse models of human Tay-Sachs and Sandhoff diseases.

We have generated mouse models of human Tay-Sachs and Sandhoff diseases by targeted disruption of the Hexa (alpha subunit) or Hexb (beta subunit) genes, respectively, encoding lysosomal beta-hexosaminidase A (structure, alpha) and B (structure, beta beta). Both mutant mice accumulate GM2 ganglioside in brain, much more so in Hexb -/- mice, and the latter also accumulate glycolipid GA2. Hexa -/- mice suffer no obvious behavioral or neurological deficit, while Hexb -/- mice develop a fatal neurodegenerative disease, with spasticity, muscle weakness, rigidity, tremor and ataxia. The Hexb -/- but not the Hexa -/- mice have massive depletion of spinal cord axons as an apparent consequence of neuronal storage of GM2. We propose that Hexa -/- mice escape disease through partial catabolism of accumulated GM2 via GA2 (asialo-GM2) through the combined action of sialidase and beta-hexosaminidase B.

Animals↗

PubMed1996

Characterization of cyclophilin 40: highly conserved protein that directly associates with Hsp90.

Cyclophilin 40 (CyP4O) is a recently identified member of the cyclophilin family that may be a component of unactivated steroid receptor complexes. It consists of an N-half portion that is highly homologous to cyclophilin A and has peptidyl prolyl isomerase (PPIase) activity, and a C-half portion that resembles the C-terminal portion of FKBP52 (FK506 binding protein 52), another component of unactivated steroid receptor complexes. To better understand the structure and functional characteristics of this new class of cyclophilin, we have raised monoclonal antibodies against the C-half portion of human CyP4O. Immunostaining with the antibodies showed its preferential localization in cytoplasm. One antibody cross-reacted with a 45 kDa protein in yeast, suggesting high conservation throughout evolution. A CyP4O-associated protein was isolated from rabbit reticulocyte lysate by means of an affinity resin, and was identified as hsp90. The C-half portion of CyP4O was necessary and sufficient for the interaction.

Amino Acid Isomerases↗

PubMed1995

Association between sialyl Lewis(a) expression and tumor progression in melanoma.

Twenty-three primary and 27 metastatic melanoma lesions and 17 pigmented nevi lesions were tested utilizing the immunoperoxidase reaction with anti-sialyl Lewis(a) (sLea) and anti-sLex mAbs.sLea was expressed in 9, 25, and 5 and sLex was expressed in 6, 11, and 2 of these lesions, respectively. Expression of sLea in melanocytic tumors is associated with tumor progression. Serum levels of sLea and sLex were analyzed by a sandwich assay using mAbs in 25 melanoma patients. Only 2 patients at stage 4 showed higher levels of sLea and sLex than did normal control subjects. Moreover, sLea and sLex were expressed in 1 and 2 of 5 human melanoma cell lines, respectively, and expression of sLex and sLex was not modulated by cytokines. These findings suggest that the expression of sLea in melanocytic tumors is correlated with disease progression.

Antigens, Tumor-Associated, Carbohydrate↗

PubMed1995

Tumor-associated glycoantigen, sialyl Lewis(a) as a target for bispecific antibody-directed adoptive tumor immunotherapy.

The KM231 mAb recognizing sialyl Lewis(a) (sLe(a)) epitope of glycoprotein or glycolipid expressed on various human cancers was used to prepare bispecific antibody (BSAb) containing anti-CD3 x anti-sLe(a) mAb. The effect of anti-CD3 x anti-sLe(a) BSAb on the induction of cytotoxicity by activated T cells was investigated. The activated CD3+ T cells expressing CD8 or CD4 were induced from human peripheral blood mononuclear cells by culture with recombinant IL-2 plus immobilized anti-CD3 mAb. The activated CD8+ and CD4+ T cells showed marginal cytotoxicity against tumor cells by themselves. However, addition of anti-CD3 x anti-sLe(a) BSAb resulted in a great augmentation of their cytotoxicity against gastrointestinal tumor cells. The BSAb also triggered IL-2 production of CD4+ helper/killer T cells during lysis of tumor cells. Moreover, the BSAb was demonstrated to have a potent in vivo antitumor activity against human colon cancer implanted in nude mice by combination with CD4+ helper/killer cells. These results demonstrated that sLe(a) antigen might be a good target molecule for BSAb-directed adoptive tumor immunotherapy.

Animals↗

PubMed1995

Antibodies to polysialic acid and its N-propyl derivative: binding properties and interaction with human embryonal brain glycopeptides.

There is no efficient vaccine against group B meningococcal meningitis because of tolerance induced by host tissue polysialic acid cross-reacting with the capsular polysaccharide. The specificities of polysialic acid-antibody interactions were studied using a ligand binding assay. Antibodies 735, 20-1, 2-1B, 2-2B, 5E1, and t5E1 and antibodies against N-propionylated group B meningococcal polysaccharide-tetanus toxoid conjugate (NP-4, 106-6) bound polysialylated human embryonal brain glycopeptides but not control glycopeptides or disialosyllactose, whereas antibodies 109-3 and I-627 were more specific for the N-propionylated polysaccharide. Antiganglioside antibodies (KM538, KM641) did not cross-react with polysialic acid. Human class-switched antibodies 5E1 (IgM) and t5E1 (IgG) reacted identically with all compounds tested and no temperature-dependent differences were observed. All anti-polysialosyl antibodies required a polysaccharide chain of 8-10 residues for binding independent of the immunizing antigen, animal species, or immunoglobulin class. The results suggest careful evaluation of polysialic acid cross-reactivity in vaccine development.

Antibodies, Monoclonal↗

PubMed1994

Induction of cholinergic differentiation with neurite sprouting by de novo biosynthesis and expression of GD3 and b-series gangliosides in Neuro2a cells.

The expression of a single glycosyltransferase, GD3 synthase, caused cholinergic differentiation with neurite sprouting. The cells that expressed GD3 were established from Neuro2a cells by transfection of a mammalian expression vector into which were carried a cDNA encoding GD3 synthase and the blasticidin-S-deaminase gene with a SV40 promoter, followed by selection with blasticidin-S-hydrochloride. The blasticidin-S-hydrochloride-resistant colonies derived from the cells transfected with the cDNA encoding GD3 synthase and the clonal cells (N2a-GD3) were spontaneously sprouting neurites but not those derived from cells transfected with only the vector without the cDNA encoding GD3 synthase (N2a-bsr). GD3 expression by N2a-GD3 was confirmed by immunostaining of the cells using the anti-GD3 monoclonal antibody, KM643. N2a-GD3 expressed not only GD3 but also GQ1b, one of the b-series gangliosides, whereas N2a-bsr did not express these gangliosides. Cell proliferation of N2a-GD3 was greatly reduced, as compared with that of N2a-bsr, and, after several passages, it completely stopped. In addition, N2a-GD3 expressed acetylcholine esterase, indicating that the differentiation of Neuro2a cells was induced by expression of GD3 synthase and subsequent modification of the biosynthesis and expression of gangliosides. These results strongly suggest that the de novo synthesis and expression of GD3 and/or b-series gangliosides induce neurite outgrowth and differentiation of Neuro2a cells. Exogenous GM1 stimulated the neuritogenesis of N2a-bsr but not differentiated N2a-GD3, indicating that the mechanism of neurite sprouting in this system may be overlapped en route with that of exogenous GM1.

Acetylcholinesterase↗

PubMed1994

Monoclonal antibodies distinctively recognizing the subtypes of inositol 1,4,5-trisphosphate receptor: application to the studies on inflammatory cells.

Monoclonal antibodies were raised that specifically recognize the COOH-terminal sequences and the loop sequences between the fifth and the sixth transmembrane spanning regions of human inositol 1,4,5-trisphosphate receptor (IP3R) type 1, 2 and 3. Western blot analysis using Jurkat cells, mouse cerebellum, COS-7 expressing IP3R type 3 cDNA showed that those monoclonal antibodies reacted specifically with each of these three IP3R subtypes and that they do not cross-react. These antibodies could be used for the specific immunoprecipitation of IP3Rs. Using these monoclonal antibodies, the expression profiles of IP3R-subtype proteins were found to be different among inflammatory cells such as macrophages, polymorphonuclear cells, mast cells, eosinophils, splenocytes, thymocytes and megakaryocytic cells. Usually, more than one type of IP3R were expressed in a cell simultaneously. The observation of CMK cells under immunofluorescence confocal microscopy revealed that IP3R type 1 and type 2 are located at different subcellular fractions.

Amino Acid Sequence↗

PubMed1994

Role of O-linked carbohydrate chains on leukocyte cell membranes in platelet-induced leukocyte activation.

We previously reported that activated platelets stimulated neutrophils and monocytes to produce superoxide anion (O2-) through the interaction between P-selectin and its carbohydrate ligand, sialyl Lewis X (sLeX) (Nagata, K., Tsuji, T., Todoroki, N., Katagiri, Y., Tanoue, K., Yamazaki, H., Hanai N., and Irimura, T. (1993) J. Immunol. 151, 3267-3273). In the present study, we investigated the role of cell surface carbohydrate chains of leukocytes in this process. Glycoconjugate-specific hydrolytic enzymes and inhibitors of glycosylation processing were applied. Granulocyte-like differentiated HL-60 (gHL-60) cells released an increased amount of O2- in response to activated platelets in a P-selectin-dependent manner. When HL-60 cells were differentiated in the presence of benzyl-alpha-N-acetylgalactosaminide (Bzl-alpha-GalNAc), an inhibitor of chain elongation of O-linked carbohydrates, the enhanced generation of O2- was abrogated in parallel with decrease in the expression of sLex structure and in the adhesion capacity to activated platelets. In contrast, treatment with swainsonine or 1-deoxymannojirimycin, inhibitors of processing of N-linked carbohydrate chains, did not show such effects. O-Sialoglycoprotease treatment of gHL-60 cells decreased the activated platelet-induced O2- production with concomitant reduction of cell surface sLex expression. Treatment of these cells with N-glycanase did not affect the O2- production. These results strongly suggested that serine/threonine-linked carbohydrate chains containing sLex played an essential role in the P-selectin-mediated leukocyte activation. By Western blotting analysis of gHL-60 cell lysates, we identified two glycoproteins which carried sLex structures and were sensitive to Bzl-alpha-GalNAc treatment.

Blood Platelets↗

PubMed1994

Expression cloning of a GM3-specific alpha-2,8-sialyltransferase (GD3 synthase).

A cDNA encoding a GM3-specific alpha-2,8-sialyltransferase (GD3 synthase) was obtained from an expression cDNA library of human melanoma cell line WM266-4 by enrichment of Namalwa KJM-1 cells highly expressing GD3 using an anti-GD3 antibody and a fluorescence-activated cell sorter. Selection of B-cell line Namalwa cells expressing transfected cDNAs in the presence of anti-GD3 monoclonal antibody KM641 gave a cDNA (pAMo-GD3) encoding a protein with a type II transmembrane topology as found for mammalian glycosyltransferases. The following evidence confirms that the cDNA encodes an alpha-2,8-sialyltransferase, which specifically converts GM3 to GD3. (i) Transfection of pAMo-GD3 into Namalwa KJM-1 cells leads to the appearance of GD3 and a GD3 synthase activity. (ii) Northern blot analysis revealed a correlation between the expression of this gene and GD3 in several cell lines. (iii) The putative COOH-terminal active domain of this cloned enzyme fused with protein A has been purified with IgG-Sepharose beads and has been shown to possess GD3-synthesizing activity, excluding the possibility that the cloned cDNA encodes a transacting factor inducing a GD3 synthase. The deduced primary sequence also contains the "sialyl motif" conserved among all the sialyltransferases cloned to date. The polymerase chain reaction analysis reveals that this gene is located on chromosome 12.

Amino Acid Sequence↗

PubMed1994

Expression cloning of a novel alpha 1,3-fucosyltransferase that is involved in biosynthesis of the sialyl Lewis x carbohydrate determinants in leukocytes.

The sialyl Lewis x (NeuAc alpha 2-3Gal beta 1-4(Fuc alpha 1-3)Glc-NAc) determinants serve as ligands in the selectin-mediated adhesion of leukocytes to activated endothelium or platelets. In our efforts to identify glycosyltransferases involved in the biosynthesis of those ligands, we achieved expression cloning of a novel human alpha 1,3-fucosyltransferase termed Fuc-TVII from a THP-1 cDNA library by enrichment of the Namalwa cells highly expressing that determinant with a fluorescence-activated cell sorter. Expression of the COOH-terminal catalytic domain of Fuc-TVII showed an alpha 1,3-fucosyltransferase activity for a type II oligosaccharide with a terminal alpha 2,3-linked sialic acid among various acceptors, consistent with that in vivo acceptor specificity. Alignment of the primary sequences of five alpha 1,3-fucosyltransferases and assignment of the chromosomal location of Fuc-TVII gene, together with that acceptor specificity, indicate that Fuc-TVII consists of a unique class of the alpha 1,3-fucosyltransferase family. Determination of the expression levels of these alpha 1,3-fucosyltransferases in various cells revealed that both Fuc-TVII and a myeloid fucosyltransferase Fuc-TIV were significantly expressed in myeloid lineage cells. Fuc-TVII-transfected Namalwa cells exhibited significant binding to E-selectin in contrast to little binding of the Fuc-TIV-transfected cells. These results suggest that Fuc-TVII may participate in the biosynthesis of the selectin ligands.

Antibodies, Monoclonal↗

PubMed1994

Recombinant rat nucleoside diphosphate kinase isoforms (alpha and beta): purification, properties and application to immunological detection of native isoforms in rat tissues.

We previously demonstrated that at least two isoforms of nucleoside diphosphate (NDP) kinase, the products of two different tandemly arrayed genes, are present in rat. To understand the physiological role of each isoform, some biochemical properties of recombinant rat NDP kinase alpha- and beta-isoforms, produced in large amount, were studied. cDNAs of the two isoforms were inserted in an expression vector pET3b and recombinant enzymes were overproduced in Escherichia coli. Their primary structures were different from the native enzymes in that the latter suffer from modification of the NH2-terminal end. The two recombinant isoforms were purified from the cell lysate to apparent homogeneity by ammonium sulfate fractionation followed by three successive column chromatographies. Despite their extreme similarity in the amino-acid sequences, the two showed somewhat different enzymic properties in terms of di- and triphosphate nucleotide substrate specificity. They showed similar mobilities on SDS-PAGE as expected from their calculated molecular weight (alpha-isoform, 17,283 versus beta-isoform, 17,192) but differed in isoelectric point (alpha-isoform, pI 6.7; beta-isoform, pI 7.8) and heat stability. Polyclonal antibody which reacted with both isoforms and alpha-isoform-specific monoclonal antibodies differentially recognized native enzymes from rat tissues after the tissue extracts were separated by isoelectric focusing gel electrophoresis under a denaturation condition. The results showed that the alpha-isoform, though its amount varied from one tissue to another, was the major form in rat tissues examined compared with the beta-isoform which was detectable in brain and testis. There was no preference in their subcellular localization when examined with myelin, synaptosomal supernatant and total homogenate fractions from the rat cerebrum and cerebellum.

Amino Acid Sequence↗

PubMed1994

Chimeric anti-ganglioside GM2 antibody with antitumor activity.

Ganglioside GM2, which is one of the major gangliosides expressed on the cell surface of human tumors of neuroectodermal origin, has been focused on as a target molecule for passive immunotherapy. GM2 is thought to be one of the T-cell-independent antigens and to elicit only IgM antibody responses in rodents and humans. We have previously established two murine anti-GM2 monoclonal antibodies with high specificity and strong binding activity, KM696 and KM697, both of which are of the IgM class. Variable heavy and light chain complementary DNAs of these two murine monoclonal antibodies were cloned and used in the construction of mouse/human IgG1 chimeric antibodies, KM966 and KM967, respectively, in this study. One of the chimeric antibodies, KM966, retained strong and specific reactivity with GM2 and showed the similarity of the binding activity with tumor cell lines to that of the original murine monoclonal antibody. Indirect immunofluorescence staining of tumor cell lines with the chimeric KM966 revealed that the antigen was expressed in substantial amounts on pulmonary tumor cells and leukemia cells as well as neuroectodermal origin tumor cells. When human serum and human peripheral blood mononuclear cells were used as effectors in complement-dependent cytotoxicity and antibody-dependent cell-mediated cytotoxicity, respectively, chimeric KM966 was fully effective in killing GM2-expressing tumor cells. In addition, i.v. injection of chimeric KM966 markedly suppressed the establishment of human tumor xenografts in nude mice. Taken together, chimeric KM966 is the first antibody of the human IgG class to ganglioside GM2 and has strong antitumor activity both in vitro and in vivo. It is likely that chimeric KM966 will be a useful agent for passive immunotherapy of human cancer.

Amino Acid Sequence↗