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Biomedical subjects

H Koprowski

Publications and source records attributed to H Koprowski.

At least 253 records · Page 14Linked to original sources

Normal salivary mucin contains the gastrointestinal cancer-associated antigen detected by monoclonal antibody 19-9 in the serum mucin of patients.

Monoclonal antibody 19-9 produced by a hybridoma prepared from spleen cells of a mouse immunized with a human colon carcinoma cell line, detects an antigen in sera from many patients with gastrointestinal and pancreatic cancer. This antibody is directed against a carbohydrate with the sugar sequence (Formula: see text) In many gastrointestinal and pancreatic cancers this sequence occurs in a monosialoganglioside containing a sialylated Lea-active pentasaccharide (sialylated lacto-N-fucopentaose II, IV3-alpha-NeuNAc-III4-alpha-Fuc-LcOse4). In the sera of cancer patients the antigen occurs as a mucin. The antigen is also found in salivary mucin from many normal individuals belonging to the Le(a+b-) or Le(a-b+) blood group but not in salivary mucin from normal individuals belonging to the Le(a-b-) blood group. There is more antigen in mucin from individuals belonging to the Le(a+b-) blood group than in mucin from individuals belonging to the Le(a-b+) blood group.

Antibodies, Monoclonal↗

Differences in cell-to-cell spread of pathogenic and apathogenic rabies virus in vivo and in vitro.

Pathogenic parental rabies virus and apathogenic variant virus were shown to differ in their ability to infect neurons in vivo and neuroblastoma cells in vitro. After intracerebral inoculation, the distribution of infected neurons in the brain was similar for both viruses, but the rate of spread throughout the brain, the number of infected neurons, and the degree of cellular necrosis were much lower in the case of apathogenic virus. After adsorption to mouse neuroblastoma cells, apathogenic virus was less rapidly internalized than pathogenic virus, and cell-to-cell spread of apathogenic variant virus was completely prevented by the addition of rabies virus-neutralizing antibody, whereas the spread of pathogenic virus was not affected.

Animals↗

Amplification of rabies virus-induced stimulation of human T-cell lines and clones by antigen-specific antibodies.

The effect of antigen-specific antibodies on the response of human T-cell lines and clones to rabies virus was studied. Plasmas from rabies-immune vaccine recipients, but not those from nonimmune individuals, enhanced the proliferative response of rabies-reactive T cells to whole inactivated virus or to the purified glycoprotein and nucleocapsid from the rabies virion. Rabies-immune plasma also increased the antigen-induced production of gamma interferon by the rabies-specific T-cell lines. Experiments performed on T-cell clones specific for either rabies glycoprotein or nucleocapsid showed that immune plasma as well as antiglycoprotein and antinucleoprotein murine monoclonal antibodies possessed the capacity to increase significantly the antigen-induced proliferative responses of these clones. The overall results indicate that this in vitro effect of antigen-specific antibodies on the response of regulatory T lymphocytes to rabies virus could be an important factor in the development of effective immune responses in vivo to rabies virus.

Antibodies, Viral↗

Current status and strategies for vaccines against diseases induced by human T-cell lymphotropic retroviruses (HTLV-I, -II, -III).

The continuous increase in the number of acquired immunodeficiency syndrome (AIDS) cases for whom no effective therapy is currently possible mandates attempts at developing primary prevention by a vaccine. Two basic unknowns are considered important: the identification of virus-exposed, protected individuals; and the isolation of the antigen which contains epitopes which induce a protective response. Although almost all individuals exposed to human T-cell leukemia-lymphoma virus type III (HTLV-III) develop antibody, most of these do not have neutralizing antibody. The antigen which can induce the response is the major external glycoprotein, which is highly glycosylated (Mr 120,000). Based on past attempts at developing vaccines against retroviruses, the most feasible configuration will be the glycoprotein linked to its transmembrane protein and assembled into micelles or rosettes by hydrophobic bonding. Any virus preparation containing nucleic acids could be considered less safe. An advanced version of such a viral subunit presentation is matrices composed of immunostimulating complexes. This format could also be useful for the inoculation of sequence determined synthetic peptides or genetically engineered readout products of the viral envelope (env) gene. Potential problems exist in that there is extensive heterogeneity among various HTLV-III isolates, particularly in the env gene. This fact and the known relationship of HTLV-III to some lentiviruses suggest that functional antigenic variation could be encountered. The methodology of developing a vaccine against the retroviruses causing AIDS should also be helpful in designing vaccine strategies against human leukemia and lymphomas caused by other members of this virus family.

Acquired Immunodeficiency Syndrome↗

Longitudinal analysis of three intrathecally produced immunoglobulin subpopulations in an MS patient.

Four murine anti-idiotypic (a-Id) hybridoma antibodies were produced against immunoglobulins (Ig) present in the cerebrospinal fluid (CSF) obtained from an MS patient 2 mo after the onset of disease. The four a-Id antibodies were shown to delineate idiotopes present on three distinct Ig subpopulations designated ID-19, ID-40, and ID-97. All three Ig subpopulations were produced in part by intrathecally localized B cells, together making up approximately 5% of the total CSF-Ig 2 mo after the onset of disease. Longitudinal analysis of the concentration of these Ig subpopulations in CSF showed that two subpopulations, ID-40 and ID-97, exhibited a regular relation to the clinical course of the disease, i.e., were decreased (ID-40) or increased (ID-97) in the first CSF sample obtained after two consecutive exacerbations. Screening of sera from 52 optic neuritis patients and 51 heterologous MS patients revealed that one MS patient's serum contained an Ig subpopulation that was idiotypically cross-reactive with ID-97. So far, screening of these Ig subpopulations for reaction with several viruses (measles, parainfluenza type 1, influenza type A, cytomegalovirus, herpes simplex virus, rubella virus, poliovirus, murine encephalomyelitis viruses, and reovirus) and myelin basic protein has failed to reveal their antigen specificities.

Adult↗

Recombinant gamma-interferon induces changes in expression and shedding of antigens associated with normal human melanocytes, nevus cells, and primary and metastatic melanoma cells.

Recombinant gamma-interferon (rIFN-gamma) induced or augmented the expression of HLA-DR class II antigens on melanocytes isolated from newborn foreskin, from congenital, common acquired, and dysplastic nevi, and from primary and metastatic melanoma. The stimulatory effect of rIFN-gamma on HLA-DR antigen expression was suppressed by the addition of the phorbol ester TPA or its analog PDBu to the culture medium. Whereas rIFN-gamma did not significantly alter the expression of melanoma-associated, non-class II antigens on melanoma cells, there was a marked decrease in the expression of antigens associated with nevus cells. In addition, rIFN-gamma stimulated shedding of antigens. Increased antigen shedding was most apparent for an intracytoplasmic melanoma-associated protein of 80kd, followed by the ganglioside GD2 and by an alkali labile ganglioside. The simultaneous stimulation of class II antigen expression and shedding of melanoma-associated antigens as well as suppression of nevus-associated antigen expression could play an important role in the host immune response to premalignant and malignant melanocytic lesions.

Antigens, Neoplasm↗

The interaction of murine IgG subclass proteins with human monocyte Fc receptors.

The use of murine monoclonal antibodies in the immunotherapy of human disease has prompted interest in the interactions of murine IgG with Fc receptors (FcR) expressed on human effector cells. We examined the heterocytophilic interactions between monomeric murine IgG subclass proteins and the FcR expressed on human monocytic cells (peripheral blood monocytes and interferon (IFN)-gamma-induced U937 cells). All four murine IgG2a antibodies and both murine IgG3 antibodies that were tested bound to human monocyte FcR with high affinity (10(8) to 10(9) M-1). By contrast, the affinities of four murine IgG1 and four IgG2b monomers were 100-fold to 1000-fold lower than the affinity of the human IgG1-FcR interaction. A 68,000 to 72,000 dalton protein was isolated by affinity chromatography from blood monocytes and from IFN-gamma-induced U937 cells on murine IgG2a, IgG3, and human IgG immunoadsorbents. In binding assays with IFN-stimulated U937 cells, murine IgG2a and IgG3 antibodies showed complete cross-blocking with a human IgG1 myeloma protein, indicating that murine and human IgG interact with the same population of Fc-binding proteins. No evidence for heterogeneity of cross-reactive FcR was observed. The ability of murine IgG2a and IgG3 monomers to compete with human IgG1 monomers for binding to human monocyte FcR suggests the potential usefulness of antibodies of these isotypes in the immunotherapy of diseases in which monocyte- or macrophage-mediated, antibody-dependent cellular cytotoxicity may play a role in the modification or remission of disease.

Animals↗

Monoclonal antibody-dependent murine macrophage-mediated cytotoxicity against human tumors is stimulated by lentinan.

The beta (1----3) glucan lentinan was tested for its capacity to increase the cytotoxic effect of murine peritoneal macrophages for human tumor cells in the presence of monoclonal antibodies (MAbs). Activity was maximum in macrophages obtained on day 5 following intraperitoneal injection of CBA mice with 2.5 mg of lentinan per kg body weight. Macrophages stimulated by lentinan were cytotoxic in conjunction with IgG1, IgG2a and IgG3 MAbs, but not with IgG2b, IgM, or IgA MAbs. The demonstration of a similar enhancing effect by lentinan on human macrophages might have implications for potentiating the tumoricidal effect of these macrophages in the presence of tumor antigen-specific MAbs.

Animals↗

Inhibition of human tumor growth by IgG2A monoclonal antibodies correlates with antibody density on tumor cells.

Eight monoclonal antibodies (MAb) of IgG2a isotype that were produced against human melanomas were tested for tumor growth-inhibiting properties in nude mice injected with human melanoma cells of various origins. Four of the eight MAb inhibited growth of these tumors, and all four of these antibodies reacted in antibody-dependent macrophage-mediated cytotoxicity (ADMC) assays in vitro. The MAb that were inactive in vivo also did not react in these assays in vitro. The number of antibody-binding sites per cell on the tumor cell surface was significantly higher for tumoricidal MAb as compared to unreactive MAb. On the other hand, the percentage of tumor cells binding the MAb and the binding affinity to these cells were the same for the two groups of MAb. Also, tumoricidal and nontumoricidal MAb bound with similar affinity and antibody density to Fc receptors on macrophages. The importance of the number of antibody sites on the tumor cell surface for tumor destruction by MAb was confirmed by the demonstration of tumoricidal effects of mixtures of MAb that were by themselves not tumoricidal. MAb binding to different molecules on melanoma cells were complementary in ADMC, whereas MAb directed to the same molecule but to different epitopes were not.

Animals↗

Phase II clinical trial of a murine monoclonal antibody cytotoxic for gastrointestinal adenocarcinoma.

A murine monoclonal antibody (MAb) which binds to human metastatic gastrointestinal adenocarcinomas can be administered safely and has tumor effects in some patients. Its therapeutic effect was assessed in 20 patients with measurable advanced colorectal carcinoma that was refractory to prior surgical resection, chemotherapy, and/or radiotherapy. All patients had agreed to receive no other therapy at the time of MAb administration and follow-up evaluation. In one patient, tumor at all known sites responded after a single i.v. injection of antibody. One other patient had a marked reduction in a hepatic metastasis where binding of 131I-labeled F(ab')2 MAb fragments was demonstrated but not in his abdominal wall metastases where no MAb binding could be demonstrated. In a third patient, stabilization persisting for 12 mo of an aggressively growing tumor was observed. The antibody was well tolerated in all patients, although 10 patients mounted an anti-murine immunoglobulin antibody response.

Adenocarcinoma↗

Increased sensitivity in detecting tumor-associated antigens in sera of patients with colorectal carcinoma.

A monoclonal antibody defining the Lewis blood group determinant was used to immobilize antigen in sera of patients with adenocarcinoma of the gastrointestinal tract, and a second radiolabeled antibody, which defines a gastrointestinal cancer-associated antigen (GICA), was used to detect the immobilized antigen. With this approach, elevated antigen levels were found in 34 of 49 (69%) of sera from patients with advanced colorectal carcinoma as compared with 9 of 292 (3%) of sera from patients with non-malignant gastrointestinal diseases and of healthy donors. For early primary colorectal carcinoma, the combination of anti-Lewis and anti-GICA monoclonal antibodies was more sensitive in detecting GICA than using anti-GICA antibody alone. Double determinant radioimmunoassay revealed the glycolipid determinant lacto-N-fucopentaose (LNF) III circulating in colorectal carcinoma patients' sera. 53% of patients older than 65 years had elevated levels of the LNF III determinant compared to none of age-matched, apparently healthy donors or patients with benign gastrointestinal tract lesions, and 18% of patients with inflammatory gastrointestinal tract diseases. In younger patients, the differences were less marked. Our results suggest the potential usefulness of Lewis and LNF III determinants as markers for the detection of gastrointestinal tract malignancies.

Adult↗

Efficient selection of human tumor growth-inhibiting monoclonal antibodies.

A method is described for selection early after fusion for hybridomas that secrete IgG2a monoclonal antibodies (MAbs) with binding specificity for antigens on the human tumor cells used to immunize mice. By combining this preselection method with antibody-dependent macrophage-mediated cytotoxicity assays, it was possible to select those MAbs mediating a tumoricidal effect against tumor cells in culture and inhibiting the growth of tumor xenografts in nude mice. Two such MAbs, GA733 and CO441, inhibited the growth of colorectal carcinoma cells, and one of them (GA733) was effective even when administered 6 days after implantation of tumor cells. These results suggest the potential usefulness of the 2 MAbs in immunodiagnosis and immunotherapy of human tumors.

Animals↗

Expression of gastrointestinal carcinoma-associated antigen (GICA) detected in human fetal tissues by monoclonal antibody NS-19-9.

The expression of a gastrointestinal carcinoma-associated antigen (GICA), a monosialoganglioside, was investigated in tissues from human fetuses of various gestational ages (10-40 weeks). Mouse monoclonal antibody NS-19-9, generated in mice immunized with SW1116 human colon carcinoma cells, was used along with a second polyclonal antibody to mouse IgG to detect antigen expression as visualized by means of the biotin-avidin-peroxidase assay. Sections of snap-frozen tissues or tissues fixed in 4% formaldehyde, in mercury chloride-formaldehyde, or in Bouin's solution were used. GICA was consistently detected in the mucosal epithelium of the small intestine. In contrast, the mucosal epithelium of the colon-rectum contained no detectable GICA, nor could the antigen be detected biochemically in extracts from the large intestine. GICA was usually found in the epithelium of the larynx, trachea and main bronchi as well as in the conjunctiva, lacrimal and salivary glands, gall bladder and ductus choledochus, and in the epithelium of the renal pelvis of early and mid-gestation fetuses.

Antibodies, Monoclonal↗

Lewis blood group antigens defined by monoclonal anti-colon carcinoma antibodies.

Monoclonal antibodies directed against human cancer cells were prepared by the murine hybridoma technique. These antibodies detect Lewis blood group antigens as determined by indirect solid-phase radioimmunoassay, hapten inhibition studies, and chromatogram binding assay. One monoclonal antibody is specific for the Lea terminal carbohydrate of Gal beta 1----3Glc NAc(4----1 alpha Fuc) beta 1----3LacCer. Five monoclonal antibodies react with the Leb terminal carbohydrate sequence of Fuc alpha 1----2Gal beta 1----3GlcNAc(4----1 alpha Fuc) beta 1----3LacCer, and four of these antibodies are highly specific for this glycolipid and do not react with other similar di- and monofucosylated glycolipids. One of the anti-Leb antibodies cross-reacts with blood group H glycolipid and has binding properties similar to those of the previously described antibody NS-10-17 [M. Brockhaus, J. L. Magnani, M. Blaszczyk, Z. Steplewski, H. Koprowski, K.-A. Karlsson, G. Larson, and V. Ginsburg (1981) J. Biol. Chem. 256, 13223-13225]. Two antibodies react with both the Lea and Leb antigens, though both bind preferentially to Leb.

Antibodies, Monoclonal↗

Binding of murine immunoglobulin to human tissues after immunotherapy with anticolorectal carcinoma monoclonal antibody.

An anticolorectal carcinoma antibody, 17-IA, that is of gamma 2a isotype and has been used in previous immunotherapy trials, binds to an antigen on most human colon tumors. This antigen is destroyed by the fixative and embedding procedures employed for routine histologic evaluation of tissues. It can be demonstrated by the avidin/biotin-labelled peroxidase complex (ABC) immunoperoxidase technique on briefly fixed, frozen sections of fresh human tissues. With this assay technique, the antibody is found to bind in vitro to both human colonic carcinoma and normal gastrointestinal epithelia. Tissues removed from patients having received the 17-IA antibody intravenously in an immunotherapy trial show bound antibody 1-2 after administration. This is no longer evident 3 weeks later though the antigen is present on the cell surface and is still capable of binding antibody in vitro.

Animals↗