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Biomedical subjects

H Koprowski

Publications and source records attributed to H Koprowski.

At least 199 records · Page 11Linked to original sources
PubMed1986

Cytolytic interactions between murine macrophages, tumor cells, and monoclonal antibodies: characterization of lytic conditions and requirements for effector activation.

Because of recent successes in inducing the effective rejection of neoplasms in vivo by administration of monoclonal antibodies (MAb), we analyzed lytic interactions in vitro that occur between macrophages and several combinations of tumor targets and MAb that can lead to such successful immunotherapy. Murine macrophages, interacting with MAb of the IgG1, IgG2a, IgG2b, and IgG3 isotypes directed against SW-1116 carcinoma cells, destroyed the tumor targets efficiently over 24 to 48 hr in vitro. Lysis was dependent on both concentration of the MAb and density of the macrophages. Binding and lysis of the targets in the presence of MAb of the IgG2a isotype was dependent on intact Fc gamma 2aR on the macrophages; target binding was necessary but not sufficient for subsequent lysis. The lytic step appeared to have an oxidative basis, at least in part, as shown by inhibition of lysis with a nonspecific scavenger of H2O2 or under either anaerobic or glucose-deprived conditions. TG-elicited or pyran-elicited macrophages, which are incompletely activated for antibody independent kill of tumor cells, were effective in mediating ADCC. By contrast, macrophages fully activated for direct cytolysis by administration of BCG or Propionibacterium acnes in vivo or by MAF and LPS in vitro, had diminished capacity for ADCC. A spectrum of five other tumor cells and antibodies, four of which are also involved in successful models of immunotherapy in vivo, were also killed over 48 hr more effectively by thioglycolate-elicited than by BCG-activated macrophages. Taken together, the data indicate that macrophages can lyse tumor cells in an ADCC reaction that has application to some models of the destruction of tumors in vivo, but that the lysis is slow and requires the macrophages to be activated in a specific way(s).

Animals↗
PubMed1986

Gene transfer and molecular cloning of the human NGF receptor.

Nerve growth factor (NGF) and its receptor are important in the development of cells derived from the neural crest. Mouse L cell transformants have been generated that stably express the human NGF receptor gene transfer with total human DNA. Affinity cross-linking, metabolic labeling and immunoprecipitation, and equilibrium binding with 125I-labeled NGF revealed that this NGF receptor had the same size and binding characteristics as the receptor from human melanoma cells and rat PC12 cells. The sequences encoding the NGF receptor were molecularly cloned using the human Alu repetitive sequence as a probe. A cosmid clone that contained the human NGF receptor gene allowed efficient transfection and expression of the receptor.

Animals↗
PubMed1986

Anti-idiotypic antibodies bear the internal image of a human tumor antigen.

Goat antibodies to idiotypes (anti-idiotypic antibodies; Ab2) that recognize an idiotype associated with the combining site of a BALB/c mouse IgG2a monoclonal antibody (Ab1) to human gastric carcinoma were used to immunize BALB/c mice and rabbits. A monoclonal anti-anti-idiotypic antibody (Ab3) of IgG1 isotype was obtained after immunization of mice. The Ab3 and the Ab1 showed identical binding specificities and bound with similar avidities to the same tumor antigen. The induction of Ab1-like Ab3 by Ab2 was not restricted to mice, since Ab3 could also be induced in rabbits. Both the mouse- and the rabbit-derived Ab3 bound the same gastrointestinal cancer-associated antigen as Ab1. These findings indicate that Ab2 induced the formation of antigen-specific Ab3, probably because it bears the internal image of the tumor-associated antigen. This Ab2 may therefore have potential for modulating the immune response of cancer patients to their tumors.

Animals↗
PubMed1986

Isolation and characterization of a carcinoma-associated antigen.

GA733 is a murine IgG2a monoclonal antibody (MAb) against human gastric carcinoma and is highly tumoricidal in nude mice. The GA733 antigen is a cell surface protein with two subunits of 30,000 and 40,000 daltons. The antigen isolated by immunoaffinity chromatography consists mainly of the 30,000-dalton subunit which bears the GA733 epitope. This subunit displayed several isoelectric points between 6.9 and 7.7. Anti-colon carcinoma MAb 17-1A also detects this antigen, but probably binds to a different epitope.

Antibodies, Monoclonal↗
PubMed1986

Monoclonal antibody-defined antigens of human prostate cancer cell line PC3.

Over 600 hybridomas were derived from the immunization of mice with live cells and aqueous extracts of the human prostatic carcinoma cell line PC3. A total of 26 hybridomas with restricted reactivities were selected, subcloned and antibodies tested on a variety of tumor and normal cells. Seven monoclonal antibodies showed reactivity for prostate cancer and other tumor cell lines, including breast carcinomas. Three of the antibodies obtained after immunization with live cells reacted with live cells only and three of the four antibodies obtained after immunization with cell extract reacted with cell extracts and spent culture media. The fourth antibody in the latter group was reactive only in the immunoperoxidase staining assay. Antibody PrS5 recognized a 90,000 molecular weight molecule from 125I-surface-labeled cells in immunoprecipitation analysis. Antibodies PrE3 and PrD8 detected a nonacid glycolipid pentasaccharide from PC3 cells and meconium, and a glycoprotein of 115,000 molecular weight from 125I-surface-labeled red blood cells. The similar patterns of reactivity in RIAs and antigen analysis suggest that antibodies PrE3 and PrD8 recognize the same molecule. The results emphasize the usefulness of immunohistochemistry in the testing of monoclonal antibodies and the impact of the form in which the antigen is presented on the resultant antibody specificity.

Animals↗
PubMed1986

Immunotherapy of gastrointestinal cancer with monoclonal antibodies.

Twenty patients with widespread metastatic colorectal carcinoma were infused with 500 mg of the cytotoxic IgG2a monoclonal antibody 17-1A preincubated with autologous peripheral blood leukocytes. Ten patients showed no benefit from such therapy and ten died, with a mean survival time of 7.6 +/- 4.5 months after treatment and a median survival of 6 months. In ten additional patients, the course of disease was modified by antibody therapy; disease in five of these patients stabilized, while tumor size in the other five patients decreased after therapy. Median actual survival in this group of ten patients is presently 24 months; four of these patients died of disease progression within a mean of 15 +/- 5 months. Duration of response was 10.5 +/- 6.7 months after antibody treatment. Treatment tolerance for these 20 patients was excellent in all but one patient, who experienced an anaphylactic reaction during a second infusion with 17-1A.

Adult↗
PubMed1986

Stimulation of cytotoxic T-lymphocyte responses by rabies virus glycoprotein and identification of an immunodominant domain.

The cytotoxic T-lymphocyte (CTL) response to rabies virus glycoprotein has been studied. A primary in vivo CTL response was obtained following inoculation of A/J mice with 10 micrograms of glycoprotein, but only when in the form of reconstituted glycoprotein-lipid vesicles. These glycoprotein-lipid vesicles were prepared with lipids from BHK-21 cells, and did not incorporate mouse major histocompatibility complex (MHC) antigens. Secondary in vitro stimulation of rabies virus-specific CTL was obtained with inactivated virus and with larger quantities of glycoprotein. This response, but not that induced by rabies virus-infected stimulator cells, was dependent on the presence of radiation-resistant accessory cells which could not be replaced with T-cell growth factors. An analysis of the molecular requirements for stimulation of CTL by glycoprotein revealed that cleavage by cyanogen bromide (CNBr) or limited tryptic digestion actually enhanced stimulation of CTL. In contrast, reduction and alkylation destroyed activity. Following separation of CNBr or tryptic fragments by gel electrophoresis or high-pressure liquid chromatography (HPLC) (under nonreducing conditions), a nominal determinant of glycoprotein was identified. One CNBr peptide (residues 103-178) and one peak of tryptic peptides were found to stimulate rabies virus-specific CTL. The tryptic peak was further analyzed by Edman degradation-sequencing, and found to consist of three peptides with amino terminals at residues 130, 251 and 279. This evidence suggests that a nominal determinant of glycoprotein responsible for stimulating rabies virus-specific CTL is located between residues 130-178 of the glycoprotein, and incorporates a single disulfide loop (159-169) which is necessary for biologic activity.

Animals↗
PubMed1986

Radioimmunodetection of human tumor xenografts by monoclonal antibody F(ab')2 fragments.

Experimental procedures are described for the radiolocalization of human tumors by murine monoclonal antibodies (MAb) in animal model systems. Visualization of tumor xenografts was clearer in nude mice as compared to experimentally immunosuppressed mice due to the higher viability of the tumors in nude mice. MAb localization in tumor tissue was greatly enhanced when F(ab')2 fragments rather than intact antibody molecules were used. Although tumors could be visualized with either 131I-, 123I- or 111In-labeled MAb fragments without using background subtraction, tumor-to-background ratios of radioactivity were highest for 131I-labeled fragments. 131I-labeled F(ab')2 fragments of eight MAb against human colorectal carcinoma, melanoma or lung carcinoma localized specifically only in those tumors that bound the MAb in vitro and not in unrelated tumors. Radiolabeled fragments of MAb with other specificities (anti-hepatitis virus MAb) did not localize in tumors. All MAb that inhibited tumor growth in nude mice effectively localized these tumors by gamma-scintigraphy. On the other hand, some MAb were effective in localizing tumors but ineffective in inhibiting their growth. The ability of the specific radiolabeled F(ab')2 fragments to localize in tumor grafts correlated significantly with MAb binding affinity and density of antigenic sites on tumor cells together, but not with either in vitro binding parameter alone. Thus, Scatchard analysis of MAb binding to tumor cells may be an effective means to screen for MAb with tumor radiolocalization potential.

Animals↗
PubMed1986

Chromatin binding of epidermal growth factor, nerve growth factor, and platelet-derived growth factor in cells bearing the appropriate surface receptors.

We analyzed the uptake and intracellular distribution of 125I-labeled epidermal growth factor, nerve growth factor, and platelet-derived growth factor in different cell lines that express or do not express the respective surface receptors for these factors. After 1 hr of incubation, all three growth factors were detected in the cytoplasmic fraction and in the nucleus, tightly bound to chromatin. The amount of chromatin-bound growth factors continued to increase during the incubation, and analysis at 48 hr revealed each chromatin-bound labeled growth factor in a nondegraded form. After limited digestion of chromatin with DNase II (10-20% digested sequences), specific release of all three growth factors was detected only after 1 hr of incubation but not after 24 and 48 hr, suggesting that the DNA regions involved in growth factor binding became nuclease-resistant. Binding of labeled epidermal growth factor and nerve growth factor to isolated chromatin was inhibited by monoclonal antibodies specific for the respective growth factor receptor. The data suggest that chromatin binding may represent an important step in the pathway of growth factor action.

Biological Transport↗
PubMed1986

Selective modification of NMR relaxation time in human colorectal carcinoma by using gadolinium-diethylenetriaminepentaacetic acid conjugated with monoclonal antibody 19-9.

Monoclonal antibody 19-9 (mAb 19-9) against human colon adenocarcinoma was conjugated with gadolinium X diethylenetriaminepentaacetic acid (Gd X DTPA) and used as a contrast agent in nuclear magnetic resonance (NMR) in an effort to improve tumor target selectivity in nude mice. The data indicate that Gd X DTPA-mAb 19-9 in solution decreased the T1 relaxation of water protons at 90 MHz in direct proportion to the gadolinium concentration, and this effect was greater than in Gd X DTPA solutions. T1 relaxation time at 90 MHz, measured in tumors removed from nude mice 24 hr after injection of Gd X DTPA-mAb 19-9 (Gd, 20 mumol/kg; 16 DTPA molecules per mAb molecule), was significantly decreased (by 15%) as compared with the control group. Similar results were obtained in tumors from mice injected with Gd X DTPA-mAb 19-9 solutions in which Gd was used at 2, 6, or 10 mumol/kg (16 DTPA molecules per mAb molecule). These doses are lower than those commonly used for Gd X DTPA (10-100 mumol/kg) as contrast agent. Tumor localization by the Gd X DTPA-mAb 19-9 complex containing radioactive Gd (0.3 microCi/microgram of 153Gd) to confirm scintigraphy revealed significant concentrations of the complex (5% of the injected dose per gram of tissue) in the tumor. Scan images recorded in planar scintigraphy at day 5 showed good visualization of tumors.

Adenocarcinoma↗
PubMed1986

Human melanoma cell lines of primary and metastatic origin express the genes encoding the chains of platelet-derived growth factor (PDGF) and produce a PDGF-like growth factor.

Normal human melanocytes and five human melanoma cell lines were analyzed for production of platelet-derived growth factor (PDGF)-like activity. Three of the melanoma cell lines released an activity that inhibited binding of 125I-labeled PDGF to human foreskin fibroblasts and stimulated [3H]thymidine incorporation in such cells. These activities were inhibited by the addition of anti-PDGF antibodies. All three factor-producing cell lines were derived from the same patient--one originated from the primary tumor (WM 115), and two were from individual lymph-node metastases (WM 239A and WM 266-4). The factor produced by WM 266-4 cells was characterized biochemically in detail. Immunoprecipitated, the metabolically labeled factor migrated in NaDod-SO4/gel electrophoresis as a homogeneous Mr 31,000 species, which under reducing conditions was resolved into two species of Mr 16,500 and Mr 17,000, implying a dimeric structure of the molecule. The factor was purified to homogeneity. Analysis by reverse-phase high-pressure liquid chromatography of reduced and alkylated factor revealed an elution pattern identical to that of PDGF A chains. Thus, the native molecule appears to be a homodimer of PDGF A chains. Blot-hybridization analysis of poly(A)+ RNA from the cell lines with 32P-labeled PDGF A chain and B chain (SIS product) cDNA probes revealed a relative abundance of B chain transcripts in the cell line originating from the primary tumor tissue only but expression of A chain in all three cell lines. We conclude that the two structural genes encoding each of the subunit chains of PDGF can be expressed in human melanoma cells and that the two genes can be independently expressed in such cells.

Cell Line↗
PubMed1986

Oral immunization and protection of raccoons (Procyon lotor) with a vaccinia-rabies glycoprotein recombinant virus vaccine.

Animal rabies control has been frustrated by the existence of multiple wildlife reservoirs and the lack of efficacious oral vaccines. In this investigation, raccoons fed a vaccinia-rabies glycoprotein recombinant virus in a sponge bait developed rabies virus-neutralizing antibody (0.6-54.0 units) and resisted street rabies virus infection 28 and 205 days after feeding. Additional raccoons immunized by oral infusion with attenuated antigenic variants of rabies virus strains CVS-11 and ERA failed to develop rabies virus-neutralizing antibody. This work demonstrates the feasibility of a recombinant virus vaccine containing the rabies glycoprotein gene for immunization of raccoons, and possibly other wildlife, to obtain long-term protection against rabies.

Administration, Oral↗
PubMed1986

Regulation of interleukin 2 receptors on T cells from multiple sclerosis patients.

Receptors for interleukin 2 (IL-2) are absent on resting T lymphocytes and are induced by antigenic and mitogenic stimulation. After a limited time (8-12 days), these receptors on normal T cells are down-regulated despite the presence of receptor-saturating concentrations of IL-2. We report here that both antigen- and mitogen-induced T-cell lines and clones obtained from peripheral blood and cerebrospinal fluid of multiple sclerosis patients show prolonged expression of IL-2 receptors. This expression is coincident with a prolonged responsiveness to the proliferative effects of IL-2. In addition, Leu 3+, IL-2 receptor-positive T-cell clone from the cerebrospinal fluid of a multiple sclerosis patient has been established and maintained for more than 1 year without IL-2. This clone has some morphologic and histochemical properties of T cells transformed or infected by human T-lymphotropic virus type I.

Antibodies, Monoclonal↗
PubMed1986

Schwann-like cells cultured from human dermal neurofibromas. Immunohistological identification and response to Schwann cell mitogens.

Primary cultures prepared from dermal and plexiform neurofibromas contain Schwann-like cells and fibroblast-like cells. SLC are elongated and bipolar or multipolar. By indirect immunofluorescence light microscopy, living SLC bind antibodies against laminin and against nerve growth factor receptor to their surface, but not antibodies against fibronectin. In these respects, cultured SLC are indistinguishable from cultured human adult Schwann cells. FLC are flat and pleomorphic. By indirect immunofluorescence light microscopy, living FLC bind antibodies against fibronectin but not against laminin or NGFR. In these respects, cultured FLC are indistinguishable from cultured human adult endoneurial fibroblasts. Considerable purification of viable SLC from SLC/FLC mixed cultures can be achieved by flow cytofluorometry using a monoclonal anti-NGFR antibody. Tritiated thymidine radioautography indicated that mitosis of SLC in mixed SLC/FLC cultures prepared from dermal neurofibromas is infrequent in MEM with 10% calf serum, more frequent in RPMI 1640 medium with 15% fetal calf serum. Central nervous system axolemmal fragments (rat or human) elicited a greater than 10-fold SLC proliferative response in mixed SLC/FLC cultures from three of seven dermal neurofibromas (from six patients with neurofibromatosis), but had no effect on SLC mitosis in cultures from the other four dermal neurofibromas. SLC mitosis was inhibited by concentrations of cyclic adenosine 3',5'-monophosphate analogues known to stimulate proliferation of normal rat Schwann cells. Glial growth factor partially purified from bovine pituitaries stimulated SLC mitosis both in SLC/FLC mixed cultures and in cultures of purified SLC. The studies we have described indicate that neurofibroma SLC can be cultured, unequivocally identified in culture by morphological and immunohistological criteria, purified, and stimulated to proliferate by several Schwann cell mitogens. Further quantitative comparisons of the baseline and mitogen-stimulated rates of proliferation of SLC and age-matched control human Schwann cells are needed, however, to determine which of the two alternate pathogenetic mechanisms for formation of neurofibromas mentioned in the introduction is correct.

Axons↗
PubMed1986

Molecular mimicry: frequency of reactivity of monoclonal antiviral antibodies with normal tissues.

More than 600 monoclonal antiviral antibodies made against 11 different viruses were screened against 14 different organs from normal uninfected mice. Of these antiviral antibodies, 21, or approximately 3.5%, reacted with specific cells in these organs. Several of these antibodies were of the multiple-organ-reactive type and recognized antigens in more than one organ. It was concluded that the reactivity of monoclonal antiviral antibodies with normal tissues is a common phenomenon.

Animals↗
PubMed1986

Isolation and characterization of human T cell lines and clones reactive to rabies virus: antigen specificity and production of interferon-gamma.

By using a preparation of inactivated rabies virus, the blood mononuclear cells from five rabies vaccine recipients were stimulated in vitro in the presence of interleukin 2. T cell lines that displayed significant proliferative responses to whole rabies virus and to preparations of rabies glycoprotein and nucleocapsid were obtained from all the individuals. Other antigens, such as diphtheria and tetanus toxoids, influenza A virus, hepatitis B surface antigen, and serum albumin, failed to induce the proliferation of the T cell lines. One of these rabies-specific T cell lines was found to proliferate in response to rabies antigens only when the antigen-presenting cells expressed homologous HLA-DR antigens. The use of mouse monoclonal antibodies specific for human T cell surface markers revealed that most of the cells of these rabies-reactive lines were of the helper/inducer class of T lymphocytes. Stimulation of the T cell lines with the rabies antigens induced the production of interferon-gamma, a lymphokine with potent antiviral activity. Several T cell clones were isolated from two of these cell lines, and most of them appeared to be specific for the antigenic components of the viral nucleocapsid. Two T cell clones specific for the rabies glycoprotein were also isolated from one of these lymphocyte interleukin 2-dependent lines. Further in vitro studies with rabies-specific T cells could help us to understand in more depth the role of regulatory T cells in the human immune response to rabies virus.

Antigens, Viral↗