Search PubMed⌕ Search

Biomedical subjects

H Koprowski

Publications and source records attributed to H Koprowski.

At least 235 records · Page 13Linked to original sources

Specific detection of anti-idiotypic immune responses in cancer patients treated with murine monoclonal antibody.

Procedures are described for the specific detection in cancer patients' sera of human antibodies raised during the course of monoclonal antibody (MAb) immunotherapy against common and idiotypic determinants of monoclonal anti-colon carcinoma antibody 17-1A. The possible interference of serum factors in these assays other than human anti-murine immunoglobulin antibodies has been virtually excluded. Minimal detectable concentrations of antibody in the various assays ranged between 0.1 and 2.8 micrograms antibody per ml serum. Thirty-five of 41 patients who raised an immune response against the administered MAb produced anti-idiotypic antibodies in concentrations of up to 42 micrograms per ml serum. Anti-idiotypic antibodies persisted in the blood for up to 475 days following the administration of a single dose of MAb. A significant proportion of the anti-idiotypic antibodies were directed against the antigen-combining site of the MAb. The importance of these results in light of possible immunoregulatory functions of the anti-idiotypic antibodies is discussed.

Animals↗

Proton NMR and fast-atom bombardment mass spectrometry analysis of the melanoma-associated ganglioside 9-O-acetyl-GD3.

A glycolipid antigen, detected by a monoclonal antibody (ME 311) obtained by immunizing mice with a human metastatic melanoma cell line (WM 46), was isolated and structurally characterized. Using immunostaining on thin-layer chromatograms for monitoring, 1.0 mg of a pure alkali-labile disialoganglioside was obtained from 23 g of packed melanoma cells (WM 164). Fractionation of the lipid extract was done on DEAE-Sepharose columns into total disialogangliosides which were repeatedly separated by high-pressure liquid chromatography. On mild alkaline treatment, the ganglioside was converted to a slower migrating species identical with a ganglioside GD3 isolated from the same source (Neu5Ac alpha 2----8Neu5Ac alpha 2----3Gal beta 1----4Glc beta 1----1-cer-amide) and specifically detected by monoclonal antibody R24. Comparison of the two gangliosides by fast-atom bombardment mass spectrometry (revealing an acetyl group on the terminal sialic acid on the alkali-labile species) and by 1H NMR (indicating the position of the acetyl group) suggested the following structure: Neu5,9Ac2 alpha 2----8Neu5Ac alpha 2----3Gal beta 1----4Glc beta 1----1-ceramide. This is identical with a ganglioside proposed earlier to exist in melanoma cells (Cheresh, D. A., Varki, A. P., Varki, N. M., Stallcup, W. B., Levine, J., and Reisfeld, R. A. (1984) J. Biol. Chem. 259, 7453-7459). Immunostaining with ME 311 antibody of cell extracts on thin-layer chromatography chromatograms revealed only this ganglioside in the melanoma cells, while normal human brain was negative. However, in one of the total ganglioside extracts tested for presence of binding with antibody ME 311, three gangliosides were found to bind. No evidence was obtained for the presence of the antigenic epitope in mucins or glycoproteins of the melanoma cells.

Antibodies, Monoclonal↗

Isolation and amino terminal sequencing of a novel melanoma-associated antigen.

The biochemical characteristics are described for a melanoma-associated glycoprotein antigen, whose expression depends on stage of tumor progression and melanocytic differentiation. This antigen, identified using a monoclonal antibody which specifically stains melanoma cells in immunoperoxidase assay of fixed tissue sections, is synthesized as a 30,000-Da precursor and then processed to a 30,000- to 60,000-Da sialylated glycoprotein. Two-dimensional gel electrophoresis of the antigen resolved more than 20 forms, heterogeneous in both charge and molecular weight. The kinetics of post-translational processing, the sensitivity of processing to tunicamycin, and the molecular weight of the oligosaccharide chains indicate that the oligosaccharides are N-linked. Amino acid sequencing of the antigen purified by immunoaffinity chromatography and by high-pressure liquid chromatography or polyacrylamide gel electrophoresis allowed the assignment of the first 20 acids.

Amino Acid Sequence↗

Gastrointestinal carcinoma-associated antigen detected by a monoclonal antibody in dysplasia and adenocarcinoma associated with chronic ulcerative colitis.

Colorectal tissue specimens from 13 patients with chronic ulcerative colitis, of whom all had epithelial dysplasia and 2 had adenocarcinoma, were tested for the presence of gastrointestinal carcinoma-associated antigen (GICA), using an immunoperoxidase technique with a monoclonal antibody (MAb) against this antigen. GICA was present in the formaldehyde-fixed and paraffin-embedded sections of dysplastic and cancer tissue but absent from normal or hyperplastic epithelium. However, the pattern and extent of staining with the antibody did not correlate with the degree of dysplasia, i.e., "mild" dysplasia was often positive, and "severe" dysplasia was sometimes negative. Changes classified as "indefinite for dysplasia but probably negative" were variable in their expression of GICA. The adenocarcinomas were selectively labelled within cell clusters. In contrast, ulcerative colitis (UC) patients with severe inflammatory changes but with no detectable dysplasia were negative for GICA. GICA could be eluted from paraffin blocks of dysplastic tissue and biochemically characterized as a glycolipid. The detection of this antigen might be a useful complement to morphological examination in discriminating between precancerous and benign epithelial lesions of the colon.

Adenocarcinoma↗

Characterization of the human melanoma nerve growth factor receptor.

Monoclonal antibodies to the human nerve growth factor receptor have been used to biochemically characterize the receptor in the human melanoma cell line A875. Labeling of A875 cell proteins by culture with [35S]cysteine or labeling of cell surface proteins with 125I followed by immunoprecipitation with anti-nerve growth factor receptor antibody reveals a receptor protein with an apparent Mr of 70,000-75,000 and an isoelectric point of 4.9-5.2. Incorporation of [3H]glucosamine into this species indicates it is a glycoprotein. The receptor becomes phosphorylated on serine residues in intact cells and in isolated membranes incubated with [gamma-32P]ATP. The receptor appears to exist, at least partially, in the form of a disulfide-linked oligomer (probably a dimer) of Mr = 75,000 subunits. Kinetic [35S]cysteine labeling studies reveal an Mr = 59,000 core protein which is glycosylated via N-linked and probably also O-linked sugar moieties to produce the mature (Mr = 70,000-75,000) receptor.

Antibodies, Monoclonal↗

Selection of monoclonal antibodies detecting serodiagnostic human tumor markers.

Monoclonal antibodies (MAbs) were selected for specific binding to spent media of cultured tumor cells. Out of more than 12,000 hybridomas screened, 19 were selected in preliminary inhibition assays for secretion of MAbs which detected antigens in cancer patients' sera. Antibody CO 29.11, which was studied in detail, bound to an antigen shed and expressed by adenocarcinoma cells of colon, stomach, pancreas and urinary bladder. CO 29.11 bound to purified sialylated Lewis a (Lea) antigen but to a different epitope and with a higher binding affinity than the MAb CA 19-9. CO 29.11 but not CA 19-9 bound weakly to unsialylated Lea antigen. In double-determinant radioimmunoassay with sera of patients with colorectal carcinoma, CO 29.11 was found to be a more sensitive marker than CA 19-9 for the detection in serum of sialylated Lea antigen.

Antibodies, Monoclonal↗

Detection of serum antibodies to Borna disease virus in patients with psychiatric disorders.

Borna disease virus causes a rare meningoencephalitis in horses and sheep and has been shown to produce behavioral effects in some species. The possibility that the Borna virus is associated with mental disorders in humans was evaluated by examining serum samples from 979 psychiatric patients and 200 normal volunteers for the presence of Borna virus-specific antibodies. Antibodies were detected by the indirect immunofluorescence focus assay. Antibodies to the virus were demonstrated in 16 of the patients but none of the normal volunteers. The patients with the positive serum samples were characterized by having histories of affective disorders, particularly of a cyclic nature. Further studies are needed to define the possible involvement of Borna virus in human psychiatric disturbances.

Adult↗

Monoclonal anti-human tumor antibodies of six isotypes in cytotoxic reactions with human and murine effector cells.

Eighty-seven murine monoclonal antibodies (MAb) produced against human tumors of various origins and representing six different immunoglobulin classes were tested for antitumor reactivity in antibody-dependent cell-mediated cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) assays. Mouse splenocytes, thioglycolate-elicited mouse peritoneal macrophages, freshly obtained nonadherent human peripheral blood lymphocytes, and human monocytes were used as effector cells, and human or rabbit serum as the source of complement. Of all four effector cell types tested, mouse macrophages showed the highest cytotoxic activity, based on net cytotoxicity, minimum requirement for Mab concentration, and effector cell number. Different immunoglobulin classes were associated with characteristic patterns of reactivity with the various effector cells or complement, independent of the target cell type used. MAb able to mediate ADCC were found among all IgG subclasses, with IgG2a and IgG3 MAb inducing lysis with all effector cell types. IgM and IgA MAb were nonreactive in the various ADCC assays, but IgM MAb were highly cytotoxic with complement.

Animals↗

Borna disease virus. A possible etiologic factor in human affective disorders?

Borna disease virus is a unique neurotropic agent that appears to have a predilection for the limbic area of the brain. In some animal species, it can produce a behavioral syndrome characterized by aggressive and passive phases. This syndrome has suggested an analogy to certain human affective disorders. In this preliminary study, we examined the possible involvement of Borna disease virus in the etiology of human mood disorders by assaying for virus-specific antibodies in 265 patients with unipolar or bipolar depression and 105 normal, healthy volunteers. Twelve patients (4.5%) and none of the healthy controls demonstrated this antibody in their serum samples. It will be necessary to replicate and extend these intriguing preliminary results to determine if Borna disease virus is possibly involved in the pathogenesis of affective disorders in humans.

Adult↗

Pharmacokinetic study of radiolabeled anti-colorectal carcinoma monoclonal antibodies in tumor-bearing nude mice.

Monoclonal antibodies (MoAbs) 17-1A and 19-9, which specifically bind human colorectal carcinoma (CRC) cells, were tested for their usefulness in localizing colorectal tumors in nude mice. One of the 131I-labeled MoAbs and an irrelevant 125I-labeled immunoglobulin of the same isotype were injected into nude mice simultaneously bearing a human CRC and a human melanoma. The percentage of the injected dose of antibody per gram of tissue, the CRC/tissue ratios of antibody distribution, and the localization indices were calculated at various time intervals (2 h to 9 days). For both MoAbs, labeling to a specific activity of 10 microCi/microgram by the iodogen method gave optimum immunoreactivity. The accumulation of MoAb 17-1A in CRC reached is maximum at 5 days and remained at this level for up to 9 days postinjection. For MoAb 19-9, which detects a circulating antigen shed by the tumor into the serum, the accumulation in the CRC was maximum at 24 h, and decreased thereafter. The CRC/organ ratios and localization indices for both MoAbs increased with time in the CRC tissue, but remained low and unchanged in the melanoma and normal tissues. Using F(ab')2 antibody fragments, faster kinetics with earlier maximum accumulation, higher tumor/organ ratios, and better localization indices were achieved than with intact MoAbs. The data obtained was useful in defining parameters which must be considered before radiolabeled MoAbs are used in cancer patients for diagnostic purposes.

Animals↗

Expression of the receptor for epidermal growth factor correlates with increased dosage of chromosome 7 in malignant melanoma.

Epidermal growth factor (EGF) receptor is expressed selectively by human melanoma cells which show the presence of an extra copy of chromosome 7. None of the cells of benign pigmented lesions (nevi) or radial growth phase (nonmetastatic) primary melanoma expressed EGF receptor and none of these cells showed an extra copy of chromosome 7. The results indicate that a single extra dose of a gene (for EGF receptor) may provide a selective advantage to cells in the late stages of tumorigenesis.

Antibodies, Monoclonal↗

Possible relationship between antigenic properties and isolation history of HSV-1 strains.

29 monoclonal anti-herpes simplex virus (HSV)-1 antibodies were produced and characterized with regard to virus neutralizing activity, intracellular or cell-surface location of viral antigens and, where possible, molecular weight of the viral protein recognized. 13 antibodies recognized viral antigens expressed on the surface of infected cells and 16 were directed to intracellular viral components. Only two antibodies exhibited virus neutralizing activity. Application of these antibodies to an antigenic comparison of standard laboratory HSV-1 strains F, HFEM, mP, Glasgow-17 and MAC revealed unique antigenic differences among these strains. The antibodies were further used in an antigenic comparison of 45 human HSV-1 isolates with defined isolation history. Except for two paired isolates from left and right trigeminal ganglia of two human cadavers, the antibody panel revealed antigenic differences among all isolates, including paired isolates from three additional cadavers. Overall, isolates from different human donors showed greater antigenic dissimilarity from each other in cell-surface associated than in intracellular antigens. The data suggest the possibility of a correlation between antigenic and biologic properties of HSV-1.

Animals↗

Human T-lymphocyte response in vitro to synthetic peptides of herpes simplex virus glycoprotein D.

Immunization of mice with a synthetic peptide that corresponds to a murine antibody-defined immunodominant domain of herpes simplex virus (HSV) glycoprotein D (gD) induced neutralizing antibodies against HSV types 1 and 2 and protected animals against a lethal challenge with HSV type 2 (Dietzschold, B., Eisenberg, R., Ponce de Leon, M., Golub, E., Hudecz, F., Varicchio, A. & Cohen, G. (1984) J. Virol. 52, 431-435). We report here that human peripheral blood T cells from HSV-seropositive and -seronegative adult donors are activated by this synthetic peptide in vitro. Interleukin-2-dependent T-cell lines established from these cultures respond specifically to peptides containing residues 1-23 of HSV gD and to a panel of overlapping peptides within this domain. The T-cell proliferative response was maximal when the majority of interleukin-2-propagated T cells were of the helper phenotype and the peptides were at least 16 amino acids long. Peptides of 8 or 12 amino acids from the carboxyl terminus were nonstimulatory. Peptide-activated T-cell lines from sero-negative donors less than 11 years old could be established in vitro, but most cells were of the suppressor/cytotoxic phenotype and demonstrated no antigen-specificity when tested with the panel of synthetic peptides.

Amino Acid Sequence↗

Monoclonal antibody to a highly glycosylated protein reacts in fixed tissue with melanoma and other tumors.

A highly glycosylated protein with a molecular weight of 30,000 to 60,000 and a protein core of 20,000 daltons has been identified by antimelanoma monoclonal antibodies. The antigenicity of this melanoma-associated glycoprotein (MAG) was not destroyed in fixed paraffin-embedded melanoma tissue, and was present in malignant cells of cutaneous superficial spreading melanomas in skin (31/33) and in half of all metastatic melanomas examined (5/10). The antigen was not expressed by normal melanocytes. The strong reactivity of dysplastic nevi with the anti-MAG antibodies was comparable to that seen in radial growth phase melanoma. Antigen expression was much weaker in compound nevi where reactivity ranged from moderate in the junctional component and the upper dermis to absent at the base of the nevus.

Antibodies, Monoclonal↗

Shared antigens of human prostate cancer cell lines as defined by monoclonal antibodies.

Eight monoclonal antibodies (MAbs) raised against human prostate cancer cell lines are described. One MAb was derived from the fusion of mouse myeloma P3x63Ag8-653 cells with spleen cells of mice immunized with DU145 prostate cancer cells. The other seven were from the fusion of myeloma lines P3x63Ag8-653 or SP2/0 with spleen cells of mice immunized with PC3, DU145 and 1013L prostate cancer cells. All of the antibodies also reacted with cell lines of other human cancer types, especially carcinomas. Immunoperoxidase staining on fixed tissue revealed strong reactivity only with antibody PrN10. Seven other antibodies seemed to bind to cell surface-associated (glyco)proteins. Antibodies PrL22 and PrO11 showed similar reactivity in radioimmunoassay, and immunoprecipitated a 160 kD molecular weight polypeptide from [125I]lactoperoxidase-labeled cells. Antibodies PrHk an PrQ12 bound to molecules with apparent MW of 115 kD and 100 kD, respectively; antibodies PrM24 and PrP14 revealed a more complex picture in immunoprecipitation of surface-labeled cells.

Antibodies, Monoclonal↗

Circulating tumor markers and assessment of response to intrahepatic chemotherapy of colon carcinoma.

To assess the change in concentrations of circulating gastrointestinal cancer-associated antigens in response to therapy, we analyzed the sera of patients with hepatic metastasis from colorectal carcinoma who were treated with intrahepatic arterial chemotherapy. Serial serum samples were assessed for the tumor-associated antigens, carcinoembryonic antigen (CEA) and the gastrointestinal cancer antigen CA 19-9. Computed axial tomographic (CAT) scans were made to assess the size of the hepatic metastasis. In 9/10 of these patients the CEA predicted tumor response within 2-6 weeks after initiation of treatment, and in 7/10 the information was supported or more dramatically demonstrated by the CA 19-9. Combining data from both tumor markers may provide a more accurate assessment of the clinical response than one antigen alone. Recurrence of hepatic metastatic growth or extrahepatic tumor also was identified by elevation of one or both circulating tumor-associated antigens prior to other laboratory or clinical evidence of tumor growth.

Adult↗