An indirect antibody assay using haptenated antigen and 125I-labelled anti-hapten antibody

International Nuclear Information System (INIS)

Aalberse, R.C.; Amsterdam Univ.

1978-01-01

Hapten (trinitrophenyl) was coupled to antigen (ovalbumin). The haptenated antigen was bound by anti-ovalbumin antibody and binding was quantitated with 125 I-labelled anti-hapten antibodies. Thus, with a single radioactive reagent, antibodies against a variety of antigens can be detected while the problems inherent in a labelled antiglobulin binding test are avoided. In the ovalbumin system, the haptenated antigen binding test proved to be approximately 20 times as sensitive as the iodinated ovalbumin binding test

In vivo instability of reduction-mediated 99mTc-labeled monoclonal antibody

International Nuclear Information System (INIS)

Sakahara, Harumi; Saga, Tsuneo; Endo, Keigo

1993-01-01

A murine monoclonal antibody that reacts with human osteogenic sarcoma (OST7) was reduced and directly labelled with 99m Tc without any loss of immunoreactivity. No fragmentation of the antibody was detected by high performance liquid chromatography after the labelling. However, SDS-PAGE analysis of the labelled antibody demonstrated the presence of low molecular weight species. Although more than 95% of the radioactivity remained bound at the antibody after incubation with human serum for 24 h, 99m Tc-labelled OST7 was cleared faster from the circulation than 125 I-labelled OST7 or 111 In-labelled OST7 in mice. (author)

SU-E-I-14: Comparison of Iodine-Labeled and Indium-Labeled Antibody Biodistributions

Energy Technology Data Exchange (ETDEWEB)

Williams, L [Retired from City of Hope Medical Center, Arcadia, CA (United States)

2014-06-01

Purpose: It is often assumed that animal biodistributions of novel proteins are not dependent upon the radiolabel used in their determination. In units of percent injected dose per gram of tissue (%ID/g), organ uptake results (u) may be obtained using either iodine or metal as radioactive labels. Iodination is preferred as it is a one-step process whereas metal labeling requires two chemical procedures and therefore more protein material. It is important to test whether the radioactive tag leads to variation in the uptake value. Methods: Uptakes of 3antibodies to Carcinoembryonic Antigen (CEA) were evaluated in a nude mouse model bearing 150 to 300 mg LS174T human colon cancer xenografts. Antibodies included diabody (56 kDa), minibody (80kDa) and intact M5A (150 kDa) anti-CEA cognates. Both radioiodine and indium-111 labels were used with uptakes evaluated at 7 time(t) points out to 96 h. Ratios (R) of u(iodine-label)/u(indium-label) were determined for liver, spleen, kidneys, lung and tumor. Results: Hepatic loss was rapid for diabody and minibody; by 24 h their R values were only 2%; i.e., uptake of iodine was 2% of that of indium for these 2 antibodies. By contrast, R for the intact cognate was 50% at that time point. Splenic results were similar. Tumor uptake ratios did not depend upon the antibody type and were 50% at 24 h. Conclusions: Relatively rapid loss of iodine relative to indium in liver and spleen was observed in lower mass antibodies. Tumor ratios were larger and independent of antibody type. Aside from tumor, the R ratio of uptakes depended on the antibody type. R values decreased monotonically with time in all tissues and for all cognates. Using this ratio, one can possibly correct iodine-based u (t) results so that they resemble radiometal-derived biodistributions.

Clearance of 131I-labeled murine monoclonal antibody from patients' blood by intravenous human anti-murine immunoglobulin antibody

International Nuclear Information System (INIS)

Stewart, J.S.; Sivolapenko, G.B.; Hird, V.; Davies, K.A.; Walport, M.; Ritter, M.A.; Epenetos, A.A.

1990-01-01

Five patients treated with intraperitoneal 131I-labeled mouse monoclonal antibody for ovarian cancer also received i.v. exogenous polyclonal human anti-murine immunoglobulin antibody. The pharmacokinetics of 131I-labeled monoclonal antibody in these patients were compared with those of 28 other patients receiving i.p.-radiolabeled monoclonal antibody for the first time without exogenous human anti-murine immunoglobulin, and who had no preexisting endogenous human anti-murine immunoglobulin antibody. Patients receiving i.v. human anti-murine immunoglobulin antibody demonstrated a rapid clearance of 131I-labeled monoclonal antibody from their circulation. The (mean) maximum 131I blood content was 11.4% of the injected activity in patients receiving human anti-murine immunoglobulin antibody compared to 23.3% in patients not given human anti-murine immunoglobulin antibody. Intravenous human anti-murine immunoglobulin antibody decreased the radiation dose to bone marrow (from 131I-labeled monoclonal antibody in the vascular compartment) 4-fold. Following the injection of human anti-murine immunoglobulin antibody, 131I-monoclonal/human anti-murine immunoglobulin antibody immune complexes were rapidly transported to the liver. Antibody dehalogenation in the liver was rapid, with 87% of the injected 131I excreted in 5 days. Despite the efficient hepatic uptake of immune complexes, dehalogenation of monoclonal antibody was so rapid that the radiation dose to liver parenchyma from circulating 131I was decreased 4-fold rather than increased. All patients developed endogenous human anti-murine immunoglobulin antibody 2 to 3 weeks after treatment

Efficient one-step direct labelling of recombinant antibodies with technetium-99m

International Nuclear Information System (INIS)

Liberatore, M.; Neri, D.; Neri, G.; Pini, A.; Lurilli, A.P.; Ponzo, F.; Spampinato, G.; Padula, F.; Pala, A.; Colella, A.C.

1995-01-01

High-affinity bacterially expressed antibody fragments can nowadays be cloned from established hybridomas or, more conveniently, isolated directly from antibody libraries displayed on filamentous phage. Such antibodies can be tagged with C-terminal peptide tags containing one cysteine residue, which represents a convenient functionalisation site for a number of applications, including technetium-99m labelling. Here we describe a simple one-step method for 99m Tc labelling of cysteine-tagged recombinant antibodies with more than 50% radionuclide incorporation. The labelled antibodies displayed full retention of immuoreactivity and good stability. (orig.)

Efficient one-step direct labelling of recombinant antibodies with technetium-99m

Energy Technology Data Exchange (ETDEWEB)

Liberatore, M. [Dipartimento di Medicina Sperimentale, Sezione di Medicina Nucleare, Policlinico Umberto I, Universita di Roma `La Sapienza` (Italy); Neri, D. [Cambridge Centre for Protein Engineering - MRC Centre (United Kingdom); Neri, G. [Dipartimento di Biologia Molecolare, Universita di Siena (Italy); Pini, A. [Dipartimento di Biologia Molecolare, Universita di Siena (Italy); Lurilli, A.P. [Dipartimento di Medicina Sperimentale, Sezione di Medicina Nucleare, Policlinico Umberto I, Universita di Roma `La Sapienza` (Italy); Ponzo, F. [Dipartimento di Medicina Sperimentale, Sezione di Medicina Nucleare, Policlinico Umberto I, Universita di Roma `La Sapienza` (Italy); Spampinato, G. [Laboratorio di Biochimica degli Ormoni Sessuali, Il Instituto di Clinica Ostetrica e Ginecologica, Universita di Roma `La Sapienza` (Italy); Padula, F. [Laboratorio di Biochimica degli Ormoni Sessuali, Il Instituto di Clinica Ostetrica e Ginecologica, Universita di Roma `La Sapienza` (Italy); Pala, A. [Laboratorio di Biochimica degli Ormoni Sessuali, Il Instituto di Clinica Ostetrica e Ginecologica, Universita di Roma `La Sapienza` (Italy); Colella, A.C. [Dipartimento di Medicina Sperimentale, Sezione di Medicina Nucleare, Policlinico Umberto I, Universita di Roma `La Sapienza` (Italy)

1995-11-01

High-affinity bacterially expressed antibody fragments can nowadays be cloned from established hybridomas or, more conveniently, isolated directly from antibody libraries displayed on filamentous phage. Such antibodies can be tagged with C-terminal peptide tags containing one cysteine residue, which represents a convenient functionalisation site for a number of applications, including technetium-99m labelling. Here we describe a simple one-step method for {sup 99m}Tc labelling of cysteine-tagged recombinant antibodies with more than 50% radionuclide incorporation. The labelled antibodies displayed full retention of immuoreactivity and good stability. (orig.)

Molecular basis for H3K36me3 recognition by the Tudor domain of PHF1

Science.gov (United States)

Musselman, Catherine A.; Avvakumov, Nikita; Watanabe, Reiko; Abraham, Christopher G.; Lalonde, Marie-Eve; Hong, Zehui; Allen, Christopher; Roy, Siddhartha; Nuñez, James K.; Nickoloff, Jac; Kulesza, Caroline A.; Yasui, Akira; Côté, Jacques; Kutateladze, Tatiana G.

2013-01-01

The PHD finger protein 1 (PHF1) is essential in epigenetic regulation and genome maintenance. Here, we demonstrate that the Tudor domain of human PHF1 binds to histone H3 trimethylated at Lys36 (H3K36me3). We report a 1.9 Å resolution crystal structure of the Tudor domain in complex with H3K36me3 and describe the molecular mechanism of H3K36me3 recognition using NMR analysis. Binding of PHF1 to H3K36me3 inhibits the ability of the Polycomb PRC2 complex to methylate H3K27 in vitro and in vivo. Laser micro-irradiation data reveal that PHF1 is transiently recruited to DNA double-strand breaks (DSBs), and PHF1 mutants impaired in the H3K36me3 interaction exhibit reduced retention at DSB sites. Together, our findings suggest that PHF1 can mediate deposition of the repressive H3K27me3 mark and acts as an early DNA damage response cofactor. PMID:23142980

Tumor localization of 131I-labeled antibodies by radionuclide imaging

International Nuclear Information System (INIS)

Ghose, T.; Tai, J.; Aquino, J.; Guclu, A.; Norvell, S.; MacDondald, A.

1975-01-01

Intravenous injections of 131 I-labeled anti-EL4 lymphoma antibodies showed progressive localization of radioactivity in EL4 transplants but not in B16 melanoma in mice carrying both tumors. Normal rabbit globulin labeled with 131 I did not localize in either tumor and cleared more slowly from the internal organs. Metastatic localization of intravenous 131 I-labeled anti-tumor antibodies was also observed in two cancer patients. (U.S.)

99mTC-dextran-antibody conjugates. Labelling procedures

International Nuclear Information System (INIS)

Marquez, M.; Westlin, J.E.; Nilsson, S.; Holmberg, A.R.

1996-01-01

Dextran forms stable chelates with 99m Tc, a radionuclide with ideal properties for planar scintigraphic and tomographic imaging. This study investigates some of the factors of importance to the formation of 99m Tc-dextran. The complex was used for the technetium labelling of a monoclonal antibody. Two radiolabelling methods were studied: Direct dextran labelling with the reductant dissolved in HCl and labelling via a weak 'transfer' chelator (tartaric acid) with the reductant dissolved in ethanol. Different conditions during the labelling reaction were studied. Finally, dextran was coupled to a monoclonal anticytokeratin antibody and the conjugate was subsequently radiolabelled with 99m Tc. Gel filtration (GFR) and thin layer chromatography (TLC) were compared as methods for estimation of the labelling efficiency. When using 10-500 μM of ligand, 5-100 μM SnC1 2 with 10-500 MBq of technetium at pH7 incubated for 10-15 min, the radiolabelling seemed optimal (70-75% labelling efficiency). It was found that 100 μM tartaric acid used as a weak intermediate chelator with SnCl 2 dissolved in ethanol improved the reproducibility of the labelling. The labelling efficiency was not affected by either the presence of oxygen or the addition of an oxygen scavenger during the labelling incubation. In general, TLC showed higher labelling efficiencies than GFR, indicating inadequate separation of the different moieties. (orig.)

Imaging of melanoma with 131I-labeled monoclonal antibodies

International Nuclear Information System (INIS)

Larson, S.M.; Brown, J.P.; Wright, P.W.; Carrasquillo, J.A.; Hellstroem, I.; Hellstroem, K.E.

1983-01-01

Mouse monoclonal antibodies and Fab fragments specific for p97, a melanoma-associated antigen, were used to image metastatic human melanoma. Preclinical studies in athymic mice showed antigen-specific uptake in melanoma xenografts, and toxicity tests in rabbits gave no evidence for tissue damage after injection of up to 100 times the amount of antibody used in humans. Six patients received 1 mg labeled antibody, and one patient received 1 mg of labeled Fab. No. toxic side effects were observed. All of the six patients had positive scans, visualizing 22 of 25 (88%) of lesions larger than 1.5 cm. In tumors from two patients, greater uptake of p97-specific, versus control IgG and Fab, respectively, was documented by biopsy. Antibodies to mouse immunoglobulin appeared in three patients receiving 1 mg or more of radiolabeled mouse antibody

PHF6 regulates phenotypic plasticity through chromatin organization within lineage-specific genes.

Science.gov (United States)

Soto-Feliciano, Yadira M; Bartlebaugh, Jordan M E; Liu, Yunpeng; Sánchez-Rivera, Francisco J; Bhutkar, Arjun; Weintraub, Abraham S; Buenrostro, Jason D; Cheng, Christine S; Regev, Aviv; Jacks, Tyler E; Young, Richard A; Hemann, Michael T

2017-05-15

Developmental and lineage plasticity have been observed in numerous malignancies and have been correlated with tumor progression and drug resistance. However, little is known about the molecular mechanisms that enable such plasticity to occur. Here, we describe the function of the plant homeodomain finger protein 6 (PHF6) in leukemia and define its role in regulating chromatin accessibility to lineage-specific transcription factors. We show that loss of Phf6 in B-cell leukemia results in systematic changes in gene expression via alteration of the chromatin landscape at the transcriptional start sites of B-cell- and T-cell-specific factors. Additionally, Phf6 KO cells show significant down-regulation of genes involved in the development and function of normal B cells, show up-regulation of genes involved in T-cell signaling, and give rise to mixed-lineage lymphoma in vivo. Engagement of divergent transcriptional programs results in phenotypic plasticity that leads to altered disease presentation in vivo, tolerance of aberrant oncogenic signaling, and differential sensitivity to frontline and targeted therapies. These findings suggest that active maintenance of a precise chromatin landscape is essential for sustaining proper leukemia cell identity and that loss of a single factor (PHF6) can cause focal changes in chromatin accessibility and nucleosome positioning that render cells susceptible to lineage transition. © 2017 Soto-Feliciano et al.; Published by Cold Spring Harbor Laboratory Press.

Monoclonal anti-elastin antibody labelled with technetium-99m

International Nuclear Information System (INIS)

Oliveira, Marcia B.N. de; Silva, Claudia R. da; Araujo, Adriano C. de; Bernardo Filho, Mario; Porto, Luis Cristovao M.S.; Gutfilen, Bianca; Souza, J.E.Q.; Frier, Malcolm

1999-01-01

Technetium-99m ( 99m Tc) is widely employed in nuclear medicine due to its desirable physical, chemical and biological properties. Moreover, it is easily available and normally is inexpensive. A reducing agent is necessary to label cells and molecules with 99m Tc and stannous chloride (Sn C L 2 ) is usually employed. Elastin is the functional protein component of the elastic fiber and it is related with some diseases such as arteriosclerosis, pulmonary emphysema and others. The present study refers to the preparation of the 99m Tc labeled monoclonal anti-elastin antibody. The monoclonal antibody was incubated with an excess of 2-iminothiolane. The free thiol groups created, were capable of binding with the reduced technetium. Labeling was an exchange reaction with 99m Tc-glucoheptonate. The labeled preparation was left at 4 deg C for one hour. Then, it was passed through a Sephadex G50 column. Various fractions were collected and counted. A peak corresponding to the radiolabeled antibody was obtained. Stability studies of the labelled anti-elastin were performed at 0,3 6, 24 hours, at both 4 deg C or room temperature. The biodistribution pattern of the 99m Tc-anti-elastin was studied in healthy male Swiss mice. The immunoreactivity was also determined. An useful labeled-anti-elastin was obtained to future immunoscintigraphic investigations. (author)

Potential application of labeled antibodies for thrombus detection

Energy Technology Data Exchange (ETDEWEB)

Ezekowitz, M.D.; Coller, B.S.; Srivastava, S.C.

1986-01-01

Labeling platelets with monoclonal antibodies in whole blood for imaging thrombi is less cumbersome than the established /sup 111/In-oxine method. 7E3, a murine monoclonal antibody directed against glycoprotein IIb and/or IIIa on both human and dog platelets was used to label canine platelets. Thrombi were induced by transcatheter placement of a copper coil followed by electrocoagulation. 7E3 was iodinated with /sup 131/I and labelled with /sup 111/In using 7E3-DTPA conjugate. Whole blood was incubated with 0.5 - 1.0 ..mu..g labeled 7E3/mL blood. In 4/4 dogs, experimental deep vein thrombi were identified using both /sup 131/I-and /sup 111/In-labeled 7E3 within 5-30 min after injection. For both isotopes, 1 h blood clearance was 54 + - 9%. In 1/3 dogs, experimental coronary thrombus could be identified ex vivo at 4 h. Clot to blood ratios ranged between 7 to 13:1. Using the /sup 111/In-oxine method, 0/3 coronary thrombi were seen. Thus, /sup 131/I-and /sup 111/In-labeled 7E3 may be used to readily identify peripheral venous thrombi. For reliable and prompt identification of coronary thrombi, more rapid clearance of the labeled platelets is required.

Immunoassay of serum polypeptide hormones by using 125I-labelled anti(-immunoglobulin G) antibodies.

Science.gov (United States)

Beck, P; Nicholas, H

1975-03-01

1. A technique for indirectly labelling antibodies to polypeptide hormones, by combining them with radioactively labelled anti-(immunoglobulin G) is described. (a) 125I-labelled anti-(rabbit immunoglobulin G) and anti-(guinea-pig immunoglobulin G) antibodies with high specific radioactivity were prepared after purification of the antibodies on immunoadsorbents containing the respective antigens. (b) Rabbit immunoglobulin G antibodies to human growth hormone, porcine glucagon and guinea-pig immunoglobulin G antibodies to bovine insulin and bovine parathyroid hormone were combined with immunoadsorbents containing the respective polypeptide hormone antigen. (c) The immunoglobulin G antibodies to the polypeptide hormones were reacted with 125-I-labelled anti-(immunoglobulin G) antibodies directed against the appropriate species of immunoglobulin G,and the anti-hormone antibodies were combined with the hormone-containing immunoadsorbent. (d) 125I-labelled anti-(immunoglobulin G) antibodies and anti-hormone antibodies were simultaneously eluted from the hormone-containing immunoadsorbent by dilute HCl, pH 2.0. After elution the anti-(immunoglobulin G) antibodies and antihormone antibodies were allowed to recombine at pH 8.0 and 4 degrees C. 2. The resultant immunoglobulin G-anti-immunoglobulin G complex was used in immunoradiometric (labelled antibody) and two-site assays of the respective polypeptide hormone. 3. By using these immunoassays, concentrations down to 90pg of human growth hormone/ml, 100 pg of bovine insulin/ml, 80 pg of bovine parathyroid hormone/ml and 150 pg of glucagon/ml were readily detected. Assays of human plasma for growth hormone and insulin by these methods showed good agreement with results obtained by using a directly 125I-labelled anti-hormone antibody in an immunoradiometric assay of human growth hormone or by radioimmunoassay of human insulin. 4. The method described allows immunoradiometric or two-site assays to be performed starting with as

Inhibition of mannosidase in hybridomas yields monoclonal antibodies with greater capacity for carbohydrate labeling

International Nuclear Information System (INIS)

Simonson, R.B.; Ultee, M.E.; Long, C.G.; Gillette, R.W.; McKearn, T.J.; Rodwell, J.D.

1988-01-01

Labeling an antibody site specifically through its carbohydrate residues preserves more of its antigen-binding activity than does labeling through protein moieties. To boost the amount of immunoglobulin G carbohydrate capable of being labeled, we treated hybridoma cells with a mannosidase inhibitor, deoxymannojirimycin (dMM). Polyacrylamide gel electrophoresis showed formation of a glycoprotein with high mannose content, in that endo-beta-N-acetylglucosaminidase H 3.2.1.96) could digest the antibody from the dMM-treated cells, but not from control cultures. Carbohydrate analysis confirmed this conclusion, indicating that the antibody from the dMM-treated cells had twice as much mannose as did the control antibody. The glucosamine content of the treated-cells' antibodies was half that of the control, and no additional carbohydrate residues were detectable in the antibodies secreted by the dMM-treated cells. We conjugated both the dMM and control antibodies through their carbohydrate to a chelator. In labeling, the dMM antibody conjugate incorporated approximately threefold as much 111 In isotope as the control conjugate. The two labeled antibodies were injected into mice and showed similar organ distributions

Development of a stable radioiodinating reagent to label monoclonal antibodies for radiotherapy of cancer

International Nuclear Information System (INIS)

Wilbur, D.S.; Hadley, S.W.; Hylarides, M.D.; Abrams, P.G.; Beaumier, P.A.; Morgan, A.C.; Reno, J.M.; Fritzberg, A.R.

1989-01-01

A method of radioiodinating monoclonal antibodies such that the labeled antibodies do not undergo in vivo deiodination has been studied. The method utilizes conjugation of succinimidyl para-iodobenzoate to the antibody. The iodobenzoate was radiolabeled by using an organometallic intermediate to facilitate the reaction. Thus, succinimidyl para-tri-n-butylstannylbenzoate was radiolabeled in 60-90% radiochemical yield and subsequently conjugated to the antibody in 80-90% yield. Animal biodistribution studies were carried out with two separate anti-melanoma antibodies (9.2.27 and NR-M1-05) labeled by this method, and examined in nude mice bearing human melanoma tumor xenografts. Very large differences in the localization of radioactivity were observed in the thyroids and stomachs of mice when the iodobenzoyl-labeled antibodies were compared with the same antibodies labeled using the chloramine-T method of radioiodination. Few other significant differences in the tissue distribution of the radioiodinated antibodies were seen

Solid phase radioimmunoassays using labelled antibodies: a conceptual framework for designing assays

International Nuclear Information System (INIS)

Kalmakoff, J.; Parkinson, A.J.; Crawford, A.M.; Williams, B.R.G.

1977-01-01

A simple theoretical model for the antigen-antibody reaction is presented and used to evaluate the optimum conditions for designing solid phase radioimmunoassays (RIA) using labelled antibodies. Both theoretical and experimental data are presented, using a wide variety of antigens and their corresponding antibodies. The types of RIA described include the direct, the indirect, the direct sandwich assays for detecting either antigen or antibody. The experimental results confirm in a semiquantitative manner that the greatest sensitivity of the RIA is achieved when the smallest amount of labelled antibody is used, that whenever possible the antigen/antibody ratio should be greater than unity(>1), and that the formation of the antigen-antibody complex is dependent on the mass action effect

A study of labelling of monoclonal antibody C50 with 99Tcm and using for radioimmunoimaging

International Nuclear Information System (INIS)

Huang Biao; Yang Min; Wang Yang; Lu Zhongwei; Guan Liang; Guo Wanhua; Zhu Chengmo

2002-01-01

Objective: To provide an accurate and scientific method of radionuclide imaging with 99 Tc m -C50. Methods: The labelled C50 was derived by imino-thiolane and ligand exchange from 99 Tc m O(GH) 2 - . HPLC ws used to analyse the modified antibody and labelled antibody, labelling efficiency was measured by paper chromatography. Radioimmunoimaging was performed on human colon tumor bearing nude mice. Results: The labelling efficiency of the labelled antibody was 97%, with 4% colloidal 99 Tc m in it; the in vitro competition test showed that 99 Tc m being bound up with the antibody at high affinity. The stability of the imino-thiolane modified antibody could be kept at 4 degree C for 3 months. The biodistribution study showed that the tumor radioactivity uptake at 24 h postinjection was the highest, the ratio of tumor to muscle was 4.03. Conclusion: The labelling method applied to the preparation of 99 Tc m labelled antibody C50 was successful, and appears to be equally applicable for labelling other antibodies

Labeling of monoclonal antibody conjugates with 90Y

International Nuclear Information System (INIS)

Motta-Hennessy, Cecilia; Sharkey, R.M.; Goldenberg, D.M.

1991-01-01

An anti-carcinoembryonic antigen (CEA) antibody, NP-4, was labeled with 90 Y using p-isothiocyanatobenzyl DTPA (SCN-Bz-DTPA) and its derivatives 1-(p-isothiocyanatobenzyl)-3-methyl-DTPA (1B3M), 2-(p-isothiocyanatobenzyl)-4-methyl-DTPA (1M3B), 1-(2)-methyl-4-isothiocyanatobenzyl-DTPA (MX-DTPA) as the chelating agents. The 90 Y conjugates were purified from unbound 90 Y by two different methods, HPLC or acrylamide size exclusion gel chromatography, in order to evaluate the best purification method. Labeling efficiency, reaction kinetics and immunoreactivity were compared to the same antibodies labeled with [ 111 In]citrate. Labeling efficiency, as determined by either HPLC or ITLC (instant thin layer chromatography), was consistently higher by ITLC than HPLC for 90 Y-labeled MAb, but equal for 111 In-labeled MAbs. Discrepancies between the 2 methods were linked to impurities in the 90 Y that remained at the origin of ITLC plates. After purification by acrylamide gel filtration, recovery was 50-60% of loaded 90 Y activity, but was more than 87% for the 111 In compounds. Using HPLC, the recovery measured 85% for 90 Y-labeled MAb and more than 93% for 111 In-labeled conjugates. Immunoreactivity of the [ 90 Y]MAb was comparable to the 111 In-labeled conjugates. These studies indicate that HPLC purification of the [ 90 Y] MAbs improves recovery of activity, and suggests that impurities found in the 90 Y and metal-binding properties of acrylamide may have contributed to the poor recoveries from acrylamide gels. (author)

A Functional Link between the Histone Demethylase PHF8 and the Transcription Factor ZNF711 in X-Linked Mental Retardation

DEFF Research Database (Denmark)

Kleine-Kohlbrecher, Daniela; Christensen, Jesper; Vandamme, Julien

2010-01-01

X-linked mental retardation (XLMR) is an inherited disorder that mostly affects males and is caused by mutations in genes located on the X chromosome. Here, we show that the XLMR protein PHF8 and a C. elegans homolog F29B9.2 catalyze demethylation of di- and monomethylated lysine 9 of histone H3 (H......3K9me2/me1). The PHD domain of PHF8 binds to H3K4me3 and colocalizes with H3K4me3 at transcription initiation sites. Furthermore, PHF8 interacts with another XMLR protein, ZNF711, which binds to a subset of PHF8 target genes, including the XLMR gene JARID1C. Of interest, the C. elegans PHF8 homolog...... is highly expressed in neurons, and mutant animals show impaired locomotion. Taken together, our results functionally link the XLMR gene PHF8 to two other XLMR genes, ZNF711 and JARID1C, indicating that MR genes may be functionally linked in pathways, causing the complex phenotypes observed in patients...

The sub-nucleolar localization of PHF6 defines its role in rDNA transcription and early processing events

Science.gov (United States)

Todd, Matthew A M; Huh, Michael S; Picketts, David J

2016-01-01

Ribosomal RNA synthesis occurs in the nucleolus and is a tightly regulated process that is targeted in some developmental diseases and hyperactivated in multiple cancers. Subcellular localization and immunoprecipitation coupled mass spectrometry demonstrated that a proportion of plant homeodomain (PHD) finger protein 6 (PHF6) protein is localized within the nucleolus and interacts with proteins involved in ribosomal processing. PHF6 sequence variants cause Börjeson–Forssman–Lehmann syndrome (BFLS, MIM#301900) and are also associated with a female-specific phenotype overlapping with Coffin–Siris syndrome (MIM#135900), T-cell acute lymphoblastic leukemia (MIM#613065), and acute myeloid leukemia (MIM#601626); however, very little is known about its cellular function, including its nucleolar role. HEK 293T cells were treated with RNase A, DNase I, actinomycin D, or 5,6-dichloro-β-D-ribofuranosylbenzimadole, followed by immunocytochemistry to determine PHF6 sub-nucleolar localization. We observed RNA-dependent localization of PHF6 to the sub-nucleolar fibrillar center (FC) and dense fibrillar component (DFC), at whose interface rRNA transcription occurs. Subsequent ChIP-qPCR analysis revealed strong enrichment of PHF6 across the entire rDNA-coding sequence but not along the intergenic spacer (IGS) region. When rRNA levels were quantified in a PHF6 gain-of-function model, we observed an overall decrease in rRNA transcription, accompanied by a modest increase in repressive promoter-associated RNA (pRNA) and a significant increase in the expression levels of the non-coding IGS36RNA and IGS39RNA transcripts. Collectively, our results demonstrate a role for PHF6 in carefully mediating the overall levels of ribosome biogenesis within a cell. PMID:27165002

A polycomb group protein, PHF1, is involved in the response to DNA double-strand breaks in human cell

Science.gov (United States)

Hong, Zehui; Jiang, Jie; Lan, Li; Nakajima, Satoshi; Kanno, Shin-ichiro; Koseki, Haruhiko; Yasui, Akira

2008-01-01

DNA double-strand breaks (DSBs) represent the most toxic DNA damage arisen from endogenous and exogenous genotoxic stresses and are known to be repaired by either homologous recombination or nonhomologous end-joining processes. Although many proteins have been identified to participate in either of the processes, the whole processes still remain elusive. Polycomb group (PcG) proteins are epigenetic chromatin modifiers involved in gene silencing, cancer development and the maintenance of embryonic and adult stem cells. By screening proteins responding to DNA damage using laser micro-irradiation, we found that PHF1, a human homolog of Drosophila polycomb-like, Pcl, protein, was recruited to DSBs immediately after irradiation and dissociated within 10 min. The accumulation at DSBs is Ku70/Ku80-dependent, and knockdown of PHF1 leads to X-ray sensitivity and increases the frequency of homologous recombination in HeLa cell. We found that PHF1 interacts physically with Ku70/Ku80, suggesting that PHF1 promotes nonhomologous end-joining processes. Furthermore, we found that PHF1 interacts with a number of proteins involved in DNA damage responses, RAD50, SMC1, DHX9 and p53, further suggesting that PHF1, besides the function in PcG, is involved in genome maintenance processes. PMID:18385154

Kinetic data of in-vivo labeled granulocytes in humans with a murine Tc-99m-labelled monoclonal antibody

International Nuclear Information System (INIS)

Becker, W.; Boerner, W.; Borst, U.; Schaefer, R.; Fischbach, W.; Pasurka, B.

1989-01-01

Twenty-five patients were examined in vivo with 99m Tc labelled monoclonal antibodies; 15 with suspected infections with an antigranulocyte antibody (BW 250/183), 10 with suspected recurrence of a colorectal carcinoma with an anti CEA antibody (BW 431/26). Both antibodies were IgG1 isotypes. In the patients with suspected infections no change of the peripheral leukocyte count could be observed after the antibody injection (1 mg, n=9; 0.05 mg, n=1; 0.25 mg, n=6). In 2 patients examined with the anti CEA antibody (2 mg), a significant decrease of the peripheral leukocyte count could be observed. The recovery rate of the 99m Tc antibody labelled granulocytes was calculated to be about 10%. The increase of the antibody-antigen binding was calculated to be 0.2%/min. In vivo the organ distribution curves demonstrated an increase of 99m Tc activity over spleen and bone marrow of 1.1%/min, which was interpreted as antigen-antibody reactivity. The organ distribution curves of the anti granulocyte antibody over spleen and bone marrow showed typical binding characteristics to the local granulocyte epitopes. The curves over other organs showed a simple perfusion pattern. The curves of the anti CEA antibody showed a perfusion pattern over all the examined organs. A sham dialysis model in one patient with renal insufficiency undergoing regular dialysis treatment demonstrated the viability of 99m Tc antibody labelled granulocytes in vivo. The kinetic patterns of the 99m Tc antibody in patients with Crohn's disease were interpreted as CEA binding of the antibody in the bowel wall. (orig.)

Technetium-99m labeling anti-amastigote polyclonal antibodies of Leishmania amazonensis

International Nuclear Information System (INIS)

Araujo, J.G.V.C.; Toledo, V.P.C.P.; Guimaraes, T.M.P.D.; Bernardo-Filho, M.; Simal, C.J.R.; Mota, L.G.; Diniz, S.O.F.; Cardoso, V.N.

2002-01-01

Anti-amastigote polyclonal antibody (IgG) was incubated with solutions of stannous chloride and sodium borohidride. After that, 3.7 MBq of technetium-99m ( 99m Tc) was added. A labeling yield of the antibody about 84% was obtained. After filtration of 99m Tc-IgG, the radiochemical purity increased from 84 to 95%. The labeling of IgG with 99m Tc did not modify the immunoreactivity of the antibody, since it was able to identify in vitro and in vivo the specific antigen of Leishmania amazonensis

Direct labelling of monomeric antibody fragments Fab' with 99mTc

International Nuclear Information System (INIS)

Li Jun; Wang Shizhen; Yang Ziyi

1994-01-01

Direct labelling method and conditions of monomeric antibody Fab' with 99m Tc were investigated. Polyclonal antibody IgG was digested with ficin to produce dimeric fragments F(ab') 2 , which was subsequently reduced to monomeric fragments Fab' with 2-mercaptoethylamine. Finally, Fab' was incubated with sodium gluconate (Sn(II)) kit solution and 99m TcO 4 - eluted at room temperature to form 99m Tc-Fab'. The labelling efficiency was 85%-95%. The stability of labelled products was satisfactory and the elimination rate was faster than 99m Tc-IgG

Lymphocyte targeting with /sup 111/In-labelled monoclonal antibodies

Energy Technology Data Exchange (ETDEWEB)

Loutfi, I.; Batchelor, J.R.; Lavender, J.P.; Epenetos, A.A.

1988-01-01

In vitro tests were conducted using human T and B cell lines, as well as whole blood, to establish the usefulness of 2 murine monoclonal antibodies (MAbs), an anti-CD5 (Pan T) and a Pan B, for potential radioimmunolocalization and therapy. Both MAbs showed specificity for the cell line in question as tested by indirect immunofluorescence and radioimmunoassay. Assays carried out on whole blood showed 40-70% of the added activity of /sup 111/In-labelled Pan B antibody binding to B cells and 20-24% of /sup 111/In-Pan T antibody binding to T cells. The amount of internalised /sup 111/In-labelled Pan B was 6% of total amount at 24 hr indicating a slow internalization process. These results should allow for in vivo targeting of normal and neoplastic B and T cells.

Current diagnostic efficacy of Tc-99m-labeled antitumor antibodies

International Nuclear Information System (INIS)

Morrison, R.T.; Lyster, D.M.; Szasz, I.; Alcorn, L.N.; Rhodes, B.A.; Breslow, K.; Burchiel, S.W.

1983-01-01

The authors have recently evaluated technetium 99 labeled antibodies specific to human chorionic gonadotropin (hCG) for the in vivo detection of a variety of human tumors. Both mouse monoclonal and sheep polyclonal antibodies were evaluated in this study. Another antibody specific to hCG studied, is an antigen-agglutinating monoclonal F(ab') 2 fragment. Some preliminary results are reported

Passive immunization with phospho-tau antibodies reduces tau pathology and functional deficits in two distinct mouse tauopathy models.

Directory of Open Access Journals (Sweden)

Sethu Sankaranarayanan

Full Text Available In Alzheimer's disease (AD, an extensive accumulation of extracellular amyloid plaques and intraneuronal tau tangles, along with neuronal loss, is evident in distinct brain regions. Staging of tau pathology by postmortem analysis of AD subjects suggests a sequence of initiation and subsequent spread of neurofibrillary tau tangles along defined brain anatomical pathways. Further, the severity of cognitive deficits correlates with the degree and extent of tau pathology. In this study, we demonstrate that phospho-tau (p-tau antibodies, PHF6 and PHF13, can prevent the induction of tau pathology in primary neuron cultures. The impact of passive immunotherapy on the formation and spread of tau pathology, as well as functional deficits, was subsequently evaluated with these antibodies in two distinct transgenic mouse tauopathy models. The rTg4510 transgenic mouse is characterized by inducible over-expression of P301L mutant tau, and exhibits robust age-dependent brain tau pathology. Systemic treatment with PHF6 and PHF13 from 3 to 6 months of age led to a significant decline in brain and CSF p-tau levels. In a second model, injection of preformed tau fibrils (PFFs comprised of recombinant tau protein encompassing the microtubule-repeat domains into the cortex and hippocampus of young P301S mutant tau over-expressing mice (PS19 led to robust tau pathology on the ipsilateral side with evidence of spread to distant sites, including the contralateral hippocampus and bilateral entorhinal cortex 4 weeks post-injection. Systemic treatment with PHF13 led to a significant decline in the spread of tau pathology in this model. The reduction in tau species after p-tau antibody treatment was associated with an improvement in novel-object recognition memory test in both models. These studies provide evidence supporting the use of tau immunotherapy as a potential treatment option for AD and other tauopathies.

Direct 99mTc labeling of monoclonal antibodies: radiolabeling and in vitro stability

International Nuclear Information System (INIS)

Garron, J.Y.; Moinereau, M.; Pasqualini, R.; Saccavini, J.C.

1991-01-01

Direct labeling involves 99m Tc binding to different donor groups on the protein, giving multiple binding sites of various affinities resulting in an in vivo instability. The stability has been considerably improved by activating the antibody using a controlled reduction reaction (using 2-aminoethanethiol). This reaction generates sulfhydryl groups, which are known to strongly bind 99m Tc. The direct 99m Tc antibody labeling method was explored using whole antibodies and fragments. Analytical methods were developed for routine evaluation of radiolabeling yield and in vitro stability. Stable direct antibody labeling with 99m Tc requires the generation of sulfhydryl groups, which show high affinity binding sites for 99m Tc. Such groups are obtained with 2-aminoethanethiol (AET), which induces the reduction of the intrachain or interchain disulfide bond, with no structural deterioration or any loss of immunobiological activity of the antibody. The development of fast, reliable analytical methods has made possible the qualitative and quantitative assessment of technetium species generated by the radiolabeling process. Labeling stability is determined by competition of the 99m Tc-antibody bond with three ligands, Chelex 100 (a metal chelate-type resin), free DTPA solution and 1% HSA solution. Very good 99m Tc-antibody stability is obtained with activated IgG (IgGa) and Fab' fragment, which makes these substances possible candidates for immunoscintigraphy use. (author)

Pharmacokinetics of indium-111-labeled antimyosin monoclonal antibody in murine experimental viral myocarditis

International Nuclear Information System (INIS)

Yamada, T.; Matsumori, A.; Watanabe, Y.; Tamaki, N.; Yonekura, Y.; Endo, K.; Konishi, J.; Kawai, C.

1990-01-01

The pharmacokinetics of indium-111-labeled antimyosin monoclonal antibody Fab were investigated with use of murine experimental viral myocarditis as a model. The biodistribution of indium-111-labeled antimyosin antibody Fab on days 3, 5, 7, 14, 21 and 28 after encephalomyocarditis virus inoculation demonstrated that myocardial uptake increased significantly on days 5, 7 and 14 (maximum on day 7) in infected versus uninfected mice (p less than 0.001). In vivo kinetics in infected mice on day 7 demonstrated that the heart to blood ratio reached a maximum 48 h after the intravenous administration of indium-111-labeled antimyosin Fab, which was considered to be the optimal time for scintigraphy. The scintigraphic images obtained with indium-111-labeled antimyosin Fab demonstrated positive uptake in the cardiac lesion in infected mice. The pathologic study demonstrated that myocardial uptake correlated well with pathologic grades of myocardial necrosis. High performance liquid chromatography revealed the presence of an antigen-antibody complex in the circulation of infected mice after the injection of indium-111-labeled antimyosin Fab. This antigen bound to indium-111-labeled antimyosin Fab in the circulation might be whole myosin and this complex may decrease myocardial uptake and increase liver uptake. It is concluded that indium-111-labeled antimyosin monoclonal antibody Fab accumulates selectively in damaged heart tissue in mice with acute myocarditis and that indium-111-labeled antimyosin Fab scintigraphy may be a useful method for the visualization of acute myocarditis

Iodine-131 labeled anti-CEA polyclonal antibody detection of gastrointestinal cancer

International Nuclear Information System (INIS)

Nabi, H.A.; Hinkle, G.H.; Olsen, J.O.; Haagensen, D.A.; Thurston, M.O.; Mojzisik, C.; Houchens, D.; Martin, E.W. Jr.

1984-01-01

To localize gastrointestinal tumor, 31 patients were injected with 1.7-2.1 mCi I-131 anti-CEA baboon polyclonal antibody. Whole body imaging at 48, 72, and occasionally 96 hrs was performed with a Signa Camera (Technicare) peaked at 364 keV with 20% window. Additional spot views were usually obtained. No subtraction methods were used. All patients had surgical and pathological confirmation of the nuclear medicine studies. Labeled antibody images were positive in 15 (8 recurrent or metastatic colorectal, 2 gastric, 1 pancreatic, 1 primary colon, and 1 breast metastatic to chest wall). In 1, antibody images were positive for metastatic deposits in para-aortic lymph nodes, but negative for primary rectal tumor. True negative images were observed in 6; false negative images in 9 (4 liver metastases, 2 rectal, 1 pancreatic, 1 mesenteric lymph node metastasis, 1 bone metastasis). In all cases, no correlation existed between preoperative CEA serum levels and imaging. I-131 labeled anti-CEA polyclonal antibody imaging proved highly efficient in detecting gastric cancer (2/2) and moderately efficient in detecting recurrent colorectal cancer (8/15). On the other hand, the I-131 labeled polyclonal anti-CEA antibody imaging was of limited value in detecting colon cancer (1/9), pancreatic cancer (1/4) and metastatic liver disease

Labeling of monoclonal antibody conjugates with sup 90 Y

Energy Technology Data Exchange (ETDEWEB)

Motta-Hennessy, Cecilia; Sharkey, R.M.; Goldenberg, D.M. (Center for Molecular Medicine and Immunology, Newark, NJ (USA))

1991-01-01

An anti-carcinoembryonic antigen (CEA) antibody, NP-4, was labeled with {sup 90}Y using p-isothiocyanatobenzyl DTPA (SCN-Bz-DTPA) and its derivatives 1-(p-isothiocyanatobenzyl)-3-methyl-DTPA (1B3M), 2-(p-isothiocyanatobenzyl)-4-methyl-DTPA (1M3B), 1-(2)-methyl-4-isothiocyanatobenzyl-DTPA (MX-DTPA) as the chelating agents. The {sup 90}Y conjugates were purified from unbound {sup 90}Y by two different methods, HPLC or acrylamide size exclusion gel chromatography, in order to evaluate the best purification method. Labeling efficiency, reaction kinetics and immunoreactivity were compared to the same antibodies labeled with ({sup 111}In)citrate. Labeling efficiency, as determined by either HPLC or ITLC (instant thin layer chromatography), was consistently higher by ITLC than HPLC for {sup 90}Y-labeled MAb, but equal for {sup 111}In-labeled MAbs. Discrepancies between the 2 methods were linked to impurities in the {sup 90}Y that remained at the origin of ITLC plates. After purification by acrylamide gel filtration, recovery was 50-60% of loaded {sup 90}Y activity, but was more than 87% for the {sup 111}In compounds. Using HPLC, the recovery measured 85% for {sup 90}Y-labeled MAb and more than 93% for {sup 111}In-labeled conjugates. Immunoreactivity of the ({sup 90}Y)MAb was comparable to the {sup 111}In-labeled conjugates. These studies indicate that HPLC purification of the ({sup 90}Y) MAbs improves recovery of activity, and suggests that impurities found in the {sup 90}Y and metal-binding properties of acrylamide may have contributed to the poor recoveries from acrylamide gels. (author).

Radioimmunoimaging in malignant melanoma with 111In-labeled monoclonal antibody 96.5

International Nuclear Information System (INIS)

Murray, J.L.; Rosenblum, M.G.; Sobol, R.E.

1985-01-01

A radiolabeled monoclonal antibody (96.5) reactive with an Mr 97,000 antigen found on over 80% of melanoma cell lines and tissue extracts was examined for its ability to detect malignant melanoma metastases in vivo. For imaging purposes, it was conjugated with diethyltriaminepentaacetic acid and subsequently labeled with 111 In by chelation. Thirty-one patients with metastatic melanoma received single injections of monoclonal antibody 96.5 at concentrations ranging from 0.5 to 20 mg and at specific activities of 111 In ranging from 0.125 to 4 mCi/mg. Total-body scans were performed at various time intervals following administration. No serious side effects were observed. Of a total of 100 previously documented metastatic sites, 50 imaged for a specificity of 50%. The number of sites imaged increased significantly as the amount of antibody administered increased relative to the average radiation dose. Considerable background uptake of isotope was observed in blood pool and other organs with gradual acquisition of label in tumor sites by 48 to 72 h. Hence, tumor imaging of melanoma using 111 In-labeled monoclonal antibody 96.5 appeared feasible, especially at antibody doses above 2 mg

Translocations disrupting PHF21A in the Potocki-Shaffer-syndrome region are associated with intellectual disability and craniofacial anomalies

DEFF Research Database (Denmark)

Kim, Hyung-Goo; Kim, Hyun-Taek; Leach, Natalia T

2012-01-01

development, and suppression of the latter led to both craniofacial abnormalities and neuronal apoptosis. Along with lysine-specific demethylase 1 (LSD1), PHF21A, also known as BHC80, is a component of the BRAF-histone deacetylase complex that represses target-gene transcription. In lymphoblastoid cell lines...... from two translocation subjects in whom PHF21A was directly disrupted by the respective breakpoints, we observed derepression of the neuronal gene SCN3A and reduced LSD1 occupancy at the SCN3A promoter, supporting a direct functional consequence of PHF21A haploinsufficiency on transcriptional...

Improved tumor localization with (strept)avidin and labeled biotin as a substitute for antibody

International Nuclear Information System (INIS)

Hnatowich, D.J.; Fritz, B.; Virzi, F.; Mardirossian, G.; Rusckowski, M.

1993-01-01

We have investigated tumor localization with labeled biotin administered subsequent to unlabeled and unconjugated streptavidin. Nude mice bearing anti-CEA tumors (LS174T) received 10 μg of 111 In-labeled anti-CEA antibody (C110) or 111 In-labeled streptavidin with sacrifice 5 h later. In an examination of pretargeting, other animals received 50 μg of unlabeled streptavidin followed 3 h later with 1 μg of 111 In-labeled biotin (EB 1 ) and sacrifice 2 h later. The biodistribution of labeled streptavidin was similar to that of labeled specific antibody except for lower blood and higher kidney levels. Tumor levels were also lower with labeled streptavidin but, because of still lower levels in liver and blood, the tumor/normal tissue ratios were improved. When unlabeled streptavidin was administered and followed by labeled biotin (pretargeting), tumor levels were further reduced modestly; however, normal tissue levels were greatly reduced such that the tumor/blood and tumor/liver ratios were 10.6 and 2.2 vs 1.5 and 0.5 for the specific antibody. Improvements were seen in all tissues sampled with the exception of kidney and muscle. A further control of labeled biotin alone (without the preinjection of streptavidin) showed minimal accumulations in all tissues with the exception of kidneys. In conclusion, the accumulation of (strept)avidin by passive diffusion in tumor may be comparable, at early times, to the accumulation of specific antibody. (author)

Site-Specific Antibody Labeling by Covalent Photoconjugation of Z Domains Functionalized for Alkyne-Azide Cycloaddition Reactions.

Science.gov (United States)

Perols, Anna; Arcos Famme, Melina; Eriksson Karlström, Amelie

2015-11-01

Antibodies are extensively used in research, diagnostics, and therapy, and for many applications the antibodies need to be labeled. Labeling is typically performed by using amine-reactive probes that target surface-exposed lysine residues, resulting in heterogeneously labeled antibodies. An alternative labeling strategy is based on the immunoglobulin G (IgG)-binding protein domain Z, which binds to the Fc region of IgG. Introducing the photoactivable amino acid benzoylphenylalanine (BPA) into the Z domain makes it possible for a covalent bond to be be formed between the Z domain and the antibody on UV irradiation, to produce a site-specifically labeled product. Z32 BPA was synthesized by solid-phase peptide synthesis and further functionalized to give alkyne-Z32 BPA and azide-Z32 BPA for Cu(I) -catalyzed cycloaddition, as well as DBCO-Z32 BPA for Cu-free strain-promoted cycloaddition. The Z32 BPA variants were conjugated to the human IgG1 antibody trastuzumab and site-specifically labeled with biotin or fluorescein. The fluorescently labeled trastuzumab showed specific staining of the membranes of HER2-expressing cells in immunofluorescence microscopy. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Improved tumor localization with (strept)avidin and labeled biotin as a substitute for antibody

International Nuclear Information System (INIS)

Hnatowich, D.J.; Fritz, B.; Virzi, F.; Mardirossian, G.; Rusckowski, M.

1993-01-01

We have investigated tumor localization with labeled biotin administered subsequent to unlabeled and unconjugated streptavidin. Nude mice bearing anti-CEA tumors (LS174T) received 10 μg of 111 In-labeled anti-CEA antibody (C110) or 111 In-labeled streptavidin with sacrifice 5 h later. In an examination of pretargeting, other animals received 50 μg of unlabeled streptavidin followed 3 h later with 1 μg of 111 In-labeled biotin (EB 1 ) and sacrifice 2 h later. The biodistribution of labeled streptavidin was similar to that of labeled specific antibody except for lower blood and higher kidney levels. Tumor levels were also lower with labeled streptavidin but, because of still lower levels in liver and blood, the tumor/normal tissue ratios were improved. When unlabeled streptavidin was administered and followed by labeled biotin (pretargeting), tumor levels were further reduced modestly; however, normal tissue levels were greatly reduced such that the tumor/blood and tumor/liver ratios were 10.6 and 2.2 vs 1.5 and 0.5 for the specific antibody. Improvements were seen in all tissues sampled with the exception of kidney and muscle. A further control of labeled biotin alone showed minimal accumulation in all tissues with the exception of kidneys. In conclusion, the accumulation of (strept)avidin by passive diffusion in tumor may be comparable, at early times, to the accumulation of specific antibody. By combining the administration of unlabeled (strept)avidin with labeled biotin, tumor targeting may potentially be improved. (author)

Pharmacokinetics of 111In-labeled anti-p97 monoclonal antibody in patients with metastatic malignant melanoma

International Nuclear Information System (INIS)

Rosenblum, M.G.; Murray, J.L.; Haynie, T.P.; Glenn, H.J.; Jahns, M.F.; Benjamin, R.S.; Frincke, J.M.; Carlo, D.J.; Hersh, E.M.

1985-01-01

Twenty-eight patients with metastatic malignant melanoma received anti-p97 murine monoclonal antibody (96.5) infused over 2 h at doses between 1 and 20 mg coupled to either 2.5 or 5.0 mCi of 111 In by the bifunctional chelating agent diethyltriaminepentaacetic acid. Clearance of 111 In from plasma closely fit an open, one-compartment mathematical model (r2 greater than 0.90). The overall half-life of 111 In plasma was approximately 31 h and did not appear to be dependent on the total dose of antibody administered. The apparent volume of distribution of the 111 In label approximated the total blood volume (7.8 +/- 0.7 liters) at the 1-mg dose and decreased to 3.0 +/- 0.14 liters at the 20-mg dose, suggesting saturation of antigenic or other extravascular binding sites at higher antibody doses. The clearance of the murine monoclonal antibody itself from plasma was measured by an enzyme-linked immunosorbent assay. The pharmacokinetics for the murine antibody in plasma also fit an open, one-compartment mathematical model. All pharmacokinetic parameters for unlabeled antibody closely paralleled those found for 111 In-labeled antibody pharmacokinetics. This suggests that the 111 In radiolabel remains complexed to the monoclonal antibody after in vivo administration. The cumulative urinary excretion of the 111 In label over 48 h was between 12 and 23% of the total administered dose and is assumed to represent 111 In-labeled chelate complex unattached to antibody. Analysis of the 111 In label in spleen, liver, heart, and kidney showed that the concentration of label in liver tissue was reduced with increasing antibody doses and coincided with changes in the apparent volume of distribution

Experimental study on 131I-labelled anti-alpha-fetoprotein antibodies in the diagnosis of rat hepatoma

International Nuclear Information System (INIS)

Terashima, Hiromi

1980-01-01

The tumor-specificity of 131 I-labelled anti-α-fetoprotein antibodies was evaluated in rats using α-fetoprotein-producing AH66C4 rat hepatoma as a model. 1) Following the 12 hour incubation of 125 I-labelled anti-α-fetoprotein antibodies and tumor cells, microautoradiography revealed marked radioactivity in and around the tumor cells. This suggested that the labelled antibodies accumulated around the cells and were combined with the α-fetoprotein secreted from the cells. 2) The tumor was transplanted subcutaneously into the thighs of rats. There was marked accumulation of 131 I-antibodies in the tumor with cyst formation, but there was none in the tumor without cyst formation. The accumulation was enhanced by the administration of non-labelled antibodies to the rats before the administration of 131 I-antibodies. The α-fetoprotein level was higher in the cyst than in any other organ. 131 I-labelled horse-γ-globulins administered as a control, also accumulated in the tumor with cyst but the degree of accumulation did not exceed that of the 131 I-antibodies. The amount of 131 I-antibodies accumulated increased, while that of 131 I-horse-γ-globulins decreased with time. This indicated that the accumulation of the γ-globulins in the tumor was nonspecific and that it was related to the blood pool. These results strongly suggest that the accumulation of 131 I-antibodies in the tumor with cyst formation was a specific antigen-antibody reaction, and the present procedure reported is applicable in the specific diagnosis of such kinds of α-fetoprotein secreting tumor. (author)

The biodistribution study of 99mTc labelled anti-CEA monoclonal antibody in tumor bearing nude mice

International Nuclear Information System (INIS)

Lou Zongxin

1992-01-01

The author report the optimal condition of 99m Tc labelling with anti-CEA monoclonal antibody using chelating of 99m Tc with dimethylformamide. The labelling rate of this method is 60%-80%, the radiochemical purity of labelling antibody over 90% and maintain its better immuno activity. The biodistribution of the tumor bearing nude mice demonstrates that as compared with the control group, 24 hours after the intraperitoneal injection the injected labelled antibody has its specific concentration in tumor tissue

Selective disulfide reduction for labeling and enhancement of Fab antibody fragments.

Science.gov (United States)

Kirley, Terence L; Greis, Kenneth D; Norman, Andrew B

2016-11-25

Many methods have been developed for chemical labeling and enhancement of the properties of antibodies and their common fragments, including the Fab and F(ab') 2 fragments. Somewhat selective reduction of some antibody disulfide bonds has been previously achieved, yielding antibodies and antibody fragments that can be labeled at defined sites, enhancing their utility and properties. Selective reduction of the two hinge disulfide bonds present in F(ab') 2 fragments using mild reduction has been useful. However, such reduction is often not quantitative and results in the reduction of multiple disulfide bonds, and therefore subsequent multiple labeling or conjugation sites are neither homogenous nor stoichiometric. Here, a simple and efficient selective reduction of the single disulfide bond linking the partial heavy chain and the intact light chain which compose the Fab fragment is accomplished utilizing tris(2-carboxyethyl)phosphine (TCEP) immobilized on agarose beads. The resultant reduced cysteine residues were labeled with several cysteine-selective fluorescent reagents, as well as by cysteine-directed PEGylation. These two cysteine residues can also be re-ligated by means of a bifunctional cysteine cross-linking agent, dibromobimane, thereby both restoring a covalent linkage between the heavy and light chains at this site, far removed from the antigen binding site, and also introducing a fluorescent probe. There are many other research and clinical uses for these selectively partially reduced Fab fragments, including biotinylation, toxin and drug conjugation, and incorporation of radioisotopes, and this technique enables simple generation of very useful Fab fragment derivatives with many potential applications. Copyright © 2016 Elsevier Inc. All rights reserved.

PHF13 is a molecular reader and transcriptional co-regulator of H3K4me2/3

DEFF Research Database (Denmark)

Chung, Ho-Ryun; Xu, Chao; Fuchs, Alisa

2016-01-01

and its molecular chromatin context. Size exclusion chromatography, mass spectrometry, X-ray crystallography and ChIP sequencing demonstrate that PHF13 binds chromatin in a multivalent fashion via direct interactions with H3K4me2/3 and DNA, and indirectly via interactions with PRC2 and RNA Pol......II. Furthermore, PHF13 depletion disrupted the interactions between PRC2, RNA PolII S5P, H3K4me3 and H3K27me3 and resulted in the up and down regulation of genes functionally enriched in transcriptional regulation, DNA binding, cell cycle, differentiation and chromatin organization. Together our findings argue...... that PHF13 is an H3K4me2/3 molecular reader and transcriptional co-regulator, affording it the ability to impact different chromatin processes....

Clinical application of antibody monoclonal humanized anti-EGFrnimotuzumab labeled

International Nuclear Information System (INIS)

Perera Pintado, Alejandro; Peña Quián, Yamilé; Batista Cuéllar, Juan F.; Prats Capote, Anaís; Torres Aroche, Leonel A.; Casacó Santana, Caridad; Sánchez Mendosa, Elvia L.; Sánchez González, Yolaine; Romero Collado, Susana; Quesada Pozo, Rodobaldo; Valladares Oviedo, Lourdes; Masquida García, Elsa M.; Leyva Montaña, René; Casacó, Angel; Ramos Suzarte, Mayra; Crombet, Tania

2016-01-01

Most malignant tumors are of epithelial origin. These are characterized by overexpression of the receptor of epidermal growth factor (EGFR), which the neoplastic cells escape the regulatory mechanisms are allowed, so its high concentration of membrane is generally associated with a poor prognosis . By binding an antibody specifically to this receptor, preventing binding of EGF latter and activation mechanism tyrosine kinase inhibiting cell mitosis and apoptosis causing tumor cell. For this reason, the EGFr has been considered as an attractive target for anti-tumor therapy. The humanized monoclonal antibody anti-EGFr nimotuzumab was developed by the Center of Molecular Immunology (Havana, Cuba). Numerous clinical trials have been developed in the Department of Clinical Research Center Isotopes (Cuba), in which it has been applied this antibody, both labeled with 99mTc for immuno gammagraphic detection of tumors, as labeled with 188 Re for radioimmunotherapy of gliomas high degree of malignancy. The aim of this paper is to show the experience of the Department of Clinical Research of CENTIS in various clinical trials with marking for both immuno gammagraphics detection of tumors, such as for radioimmunotherapy nimotuzumab. (author)

A simplified radioimmunoassay for triiodothyronine (T3) using pre-incubated labelled antigen and antibody

International Nuclear Information System (INIS)

Pillai, M.R.A.; Nagvekar, U.H.; Desai, C.N.; Mani, R.S.

1986-01-01

The development of a simplified radioimmunoassay for triiodothyronine (T 3 ) using pre-incubated labelled T 3 and antibody is described. The assay is carried out by adding 50 μl of standard or sample to 0.4 ml of pre-incubated reagent dispensed in assay tubes. The reaction was allowed to proceed for about four hours and the antigen-antibody complex precipitated by the addition of 1 cm 3 of 22% polyethylene glycol solution. Due to the high dissociation constant of T 3 -antibody complex at 37 deg C, the labelled antigen-antibody complex dissociates and thereby the unlabelled antigen binds with the antibody. The sensitivity of this assay is comparable to an assay done by the equilibrium method using the same antibody. Sixty serum samples were analyzed using this method and were compared with the equilibrium assay. (author)

Microdosimetry of monoclonal antibodies labeled with alpha emitters

International Nuclear Information System (INIS)

Fisher, D.R.

1986-01-01

The recent discovery of new techniques for the production of monoclonal antibodies (MoAB) has opened up a number of potential new applications in cancer diagnosis and therapy. Monoclonal antibodies labeled with alpha-emitting radionuclides promise to be particularly effective therapeutic agents due to the efficient cell killing ability of highly ionizing, short-range alpha particle tracks localized at specific antigen sites within the tumor mass. For a radioimmunotherapy treatment plan to be effective, one must be able to estimate the absorbed radiation dose to both tumor cells and normal tissues in the body. However, conventional methods used in nuclear medicine for estimating absorbed doses and specific absorbed fractions for radiopharmaceuticals do not apply to alpha emitters owing to their short range and the large variations in the local distribution of energy at the cellular level that result. Microdosimetric techniques developed for assessment of the radiological effects of internally deposited transuranic radionuclides take into account the statistical aspects of alpha particle track structure, energy distribution patterns, and radionuclide distribution within tissues, and provide a means for determining the number and frequency of cells irradiated, the probability densities in specific energy, and the average dose delivered to cells of interest. These techniques can be applied to the study of radiation absorbed dose from alpha-labeled monoclonal antibodies. 16 references, 6 figures

Detection of thrombi using a Tc-99m labelled antifibrin monoclonal antibody (MoAb)

International Nuclear Information System (INIS)

Wasser, M.N.J.M.

1989-01-01

This thesis presents an investigation into the possibility of immunoscintigraphic detection of thrombi using an antifibrin monoclonal antibody, and fragments of the latter. The antifibrin antibody and tis fragments were labelled with Ec-99m, which has excellent characteristics for imaging with a gamma camera. The characterization of the antifibrin antibody and its fragments, the assessment of quality of labelling with Tc-99m, and results of experiments in vitro and in animals, which show the potential of immunoscintigraphic detection, are described. (author). 142 refs.; 44 figs.; 5 tabs

Females with de novo aberrations in PHF6: clinical overlap of Borjeson-Forssman-Lehmann with Coffin-Siris syndrome.

Science.gov (United States)

Zweier, Christiane; Rittinger, Olaf; Bader, Ingrid; Berland, Siren; Cole, Trevor; Degenhardt, Franziska; Di Donato, Nataliya; Graul-Neumann, Luitgard; Hoyer, Juliane; Lynch, Sally Ann; Vlasak, Ingrid; Wieczorek, Dagmar

2014-09-01

Recently, de novo aberrations in PHF6 were identified in females with intellectual disability and with a distinct phenotype including a characteristic facial gestalt with bitemporal narrowing, prominent supraorbital ridges, synophrys, a short nose and dental anomalies, tapering fingers with brachytelephalangy, clinodactyly and hypoplastic nails, short toes with hypoplastic nails, and linear skin hyperpigmentation. In adolescent or older patients, this phenotype overlaps but is not identical with Borjeson-Forssman-Lehmann syndrome in males, caused by X-linked recessive mutations in PHF6. In younger girls there seems to be a striking phenotypic overlap with Coffin-Siris syndrome, which is characterized by intellectual disability, sparse hair and hypoplastic nails. This review will summarize and characterize the female phenotype caused by de novo aberrations in PHF6 and will discuss the overlapping and distinguishing features with Coffin-Siris syndrome. © 2014 Wiley Periodicals, Inc.

Application of 99mTc-labeled chimeric Fab fragments of monoclonal antibody A7 for radioimmunoscintigraphy of pancreatic cancer

International Nuclear Information System (INIS)

Matsumura, Hiroomi

1999-01-01

Pancreatic cancer is one of the most lethal diseases and its prognosis is still poor. To improve the survival rate, it is essential to develop new technologies for early and definitive diagnosis. In this study, chimeric Fab fragments of monoclonal antibody A7 were successfully radio-labeled with 99m Tc, preventing depression of the antigen-binding activity. 99m Tc-labeled monoclonal antibody A7, 99m Tc-labeled chimeric Fab fragments of monoclonal antibody A7, 99m Tc-labeled normal mouse IgG and 99m Tc-labeled Fab fragments of normal mouse IgG were injected intravenously into nude mice bearing human pancreatic cancer xenografts and the radioactivity was subsequently measured. The tumor accumulation was significantly higher with labeled monoclonal antibody A7 than with normal mouse IgG, and higher with chimeric Fab fragments of monoclonal antibody A7 than with Fab fragments of normal mouse IgG. The tumor/blood ratio of radioactivity increased rapidly over time with chimeric Fab fragments of monoclonal antibody A7. These results suggest that chimeric Fab fragments of monoclonal antibody A7 may be useful for diagnosing pancreatic cancer by means of radioimmunoscintigraphy. (author)

Biodistribution of Yttrium-90-Labeled Anti-CD45 Antibody in a Nonhuman Primate Model

International Nuclear Information System (INIS)

Nemecek, Eneida; Hamlin, Donald K.; Fisher, Darrell R.; Krohn, Kenneth A.; Pagel, John M.; Applebaum, F. R.; Press, Oliver W.; Matthews, Dana C.

2005-01-01

Radioimmunotherapy may improve the outcome of hematopoietic cell transplantation for hematologic malignancies by delivering targeted radiation to hematopoietic organs while relatively sparing nontarget organs. We evaluated the organ localization of yttrium-90-labeled anti-CD45 (90Y-anti-CD45) antibody in macaques, a model that had previously predicted iodine-131-labeled anti-CD-45 (131I-anti-CD45) antibody biodistribution in humans. Experimental Design: Twelve Macaca nemestrina primates received anti-CD45 antibody labeled with 1 to 2 mCi of 90Y followed by serial blood sampling and marrow and lymph node biopsies, and necropsy. The content of 90Y per gram of tissue was determined by liquid scintillation spectrometry. Time-activity curves were constructed using average isotope concentrations in each tissue at measured time points to yield the fractional residence time and estimate radiation absorbed doses for each organ per unit of administered activity. The biodistribution of 90Y-anti-CD45 antibody was then compared with that previously obtained with 131I-anti-CD45 antibody in macaques. Results: The spleen received 2,120, marrow 1,060, and lymph nodes 315 cGy/mCi of 90Y injected. The liver and lungs were the nontarget organs receiving the highest radiation absorbed doses (440 and 285 cGy/mCi, respectively). Ytrrium-90-labeled anti-CD45 antibody delivered 2.5- and 3.7-fold more radiation to marrow than to liver and lungs, respectively. The ratios previously observed with 131I-antiCD45 antibody were 2.5-and 2.2-fold more radiation to marrow than to liver and lungs, respectively. Conclusions: This study shows that 90Y-anti-CD45 antibody can deliver relatively selective radiation to hematopoietic tissues, with similar ratios of radiation delivered to target versus nontarget organs, as compared with the 131I immunoconjugate in the same animal model

Double Antibody EIA of Cortisol Using Peroxidase As Label

International Nuclear Information System (INIS)

Karim, F.M.; Hamad, A.W.R.; Hashim, A.M.

1998-01-01

An enzyme immunoassay (EIA) technique for plasma cortisol was established by using cortisol-3 (carboxymethyl) oxime covalently linked to the horseradish peroxidase as the label. An antibody raised in the rabbits against cortisol-3-(carboxy-methyl) oxime-bovline serum albumin was used as the first anti-body. Sheep anti-rabbit gamma-globulin serum with 8 percent poly-ethyleneglycol were used to separate antibody-bound and free cortisol. The enzyme activity of the bound fraction was measured with ortho-phenylene diamine as substrate. The procedure performed at room temperature was evaluated by sensitivity (50 pg/ tube). The correlation coefficient between our enzyme immunoassay technique and radioimmunoassay technique for determination of plasma cortisol was 97 percent

The in vivo fate of a 211At labelled monoclonal antibody with known specificity in a murine system

International Nuclear Information System (INIS)

Vaughan, A.T.M.; Bateman, W.J.; Fisher, D.R.

1982-01-01

A monoclonal antibody reactive against the human transferrin receptor has been labelled with the alpha and X ray emitting isotope Astatine 211. The labelling procedure does not affect the ability of the product to bind to the transferrin receptor on the human leukemic cell line HL60. Using a direct binding assay, 211 At labelled antibody can be specifically inhibited from binding to its target cells by excess unlabelled antibody. Furthermore, the binding inhibition demonstrated in this system correlates to enhanced clonogenic survival of these cells, indicating that very few atoms of 211 At/cell are required for cell death. Data obtained from labelled antibody injected into mice show that the labelled product in serum retains the ability to bind to HL60 cells in vitro, although tissue distributions of the injected activity implies that some of the radiolabel is lost from the protein. Despite this loss of label, preliminary experiments on the localization of labelled antibody to HL60 cells growing s/c in nude mice show that tumor tissue has a higher specific activity than all other tissues, other than blood, after 12 hours. This suggests that further work on the nature of label degradation in vivo is warranted in the context of potential therapeutic and diagnostic studies

Technetium-99m labelling of monoclonal antibodies for in vivo radioimmunodiagnostic use

International Nuclear Information System (INIS)

Beyers, M.

1988-01-01

The strong chelating agent diethylenetriaminepentaacetate (DTPA), either as the bicyclic or as the mixed anhydride, is most commonly used to link Tc-99m to proteinaceous compounds. A method for the batch production of DTPA-labelled antibody kits as well as a novel method of DTPA chelation of unpurified ascites fluid is given. Loss of immunoreactivity and in vivo stability occurs with this method. That DTPA conjugation is not the ideal method of labelling, is borne out by the fact that Hnatowich - a pioneer of DTPA-protein chelating - changed to an avidin-biotin labelling system. Modifications of the carbohydrate moiety have also been attempted. High molecular mass polymers with chelate-linkage to the antibodies can bind up to 150 di- or trivalent ions per mole without a loss in antigen-binding activity. Other than DTPA, several chelating agents such as bisthiosemicarbazones, metallothionein and diamide dimercaptide ligands may be used. The simple treatment of a proteinaceous substance with a disulpide-reducing agent, followed by exposure of the reduced protein to a suitable radionuclide, leads to a promising stable radiolabelled product. A Tc-99m-labelled antibody is, subject to FDA approval, scheduled for released by a Kodak-financed company in the near future

Labelled antibody techniques in glycoprotein estimation

International Nuclear Information System (INIS)

Hazra, D.K.; Ekins, R.P.; Edwards, R.; Williams, E.S.

1977-01-01

The problems in the radioimmunoassay of the glycoprotein hormones (pituitary LH, FSH and TSH and human chlorionic gonadotrophin HGG) are reviewed viz: limited specificity and sensitivity in the clinical context, interpretation of disparity between bioassay and radioimmunoassay, and interlaboratory variability. The advantages and limitations of the labelled antibody techniques - classical immonoradiometric methods and 2-site or 125 I-anti-IgG indirect labelling modifications are reviewed in general, and their theoretical potential in glycoprotein assays examined in the light of previous work. Preliminary experiments in the development of coated tube 2-site assay for glycoproteins using 125 I anti-IgG labelling are described, including conditions for maximizing solid phase extraction of the antigen, iodination of anti-IgG, and assay conditions such as effects of temperature of incubation with antigen 'hormonefree serum', heterologous serum and detergent washing. Experiments with extraction and antigen-specific antisera raised in the same or different species are described as exemplified by LH and TSH assay systems, the latter apparently promising greater sensitivity than radioimmunoassay. Proposed experimental and mathematical optimisation and validation of the method as an assay system is outlined, and the areas for further work delineated. (orig.) [de

The study of labeling with Iodine-131 of monoclonal antibody anti-CD20 used for the treatment of non-Hodgkin lymphoma

International Nuclear Information System (INIS)

Akanji, Akinkunmi Ganiyu

2006-01-01

Lymphomas are malignancies of the lymphatic system, described by Thomas Hodgkin in 1932. Traditionally, lymphomas are classified in two basic groups: Hodgkin disease and non-Hodgkin lymphoma (NHL). Patients with NHL were earlier treated with radiotherapy alone or in combination with immunotherapy using monoclonal antibody anti-CD20 (ex., Rituximab-Mabthera, Roche). However, Radioimmunotherapy is a new modality of treatment for patients with NHL, in which cytotoxic radiation from therapeutic radioisotopes is delivered to tumors through monoclonal antibodies. This study focused on labeling conditions of monoclonal antibody anti-CD20 (Rituximab-Mabthera, Roche) with iodine-131, by direct radioiodination method using Chloramine-T as oxidizing agent. Labeling parameters investigated were: Radiochemical purity (RP), method of purification, incubation time, antibody mass, oxidative agent mass, stability in vitro, stability in vivo, immunoreactivity and biological distribution performed in normal Swiss mouse. Product of high radiochemical purity was obtained with no notable difference between the methods applied. No clear evidence of direct influence of incubation time on radiochemical purity of the labeled antibody was observed. Whereas, a clear evidence of direct influence of activity on radiochemical purity of the labeled antibody was observed when antibody mass was varied. After purification, the labeled product presented radiochemical purity of approximately 100 %. Product of superior radiochemical yield was observed when standard condition of labeling was used. The labeled product presented variation in radiochemical purity using five different stabilizer conditions. The condition in which gentisic acid was combined with freeze appears more suitable and capable of minimizing autoradiolysis of the antibody labeled with high therapeutic activity of iodine-131. The labeled product presented low immunoreactivity when compared to the literature. Biological distribution in

The study of labeling with iodine-131 of monoclonal antibody anti-CD20 used for the treatment of non-Hodgkin lymphoma

International Nuclear Information System (INIS)

Akanji, Akinkunmi Ganiyu

2006-01-01

Lymphomas are malignancies of the lymphatic system, described by Thomas Hodgkin in 1932. Traditionally, lymphomas are classified in two basic groups: Hodgkin disease and non-Hodgkin lymphoma (NHL). Patients with NHL were earlier treated with radiotherapy alone or in combination with immunotherapy using monoclonal antibody anti-CD20 (ex., Rituximab-Mabthera, Roche). However, Radioimmunotherapy is a new modality of treatment for patients with NHL, in which cytotoxic radiation from therapeutic radioisotopes is delivered to tumors through monoclonal antibodies. This study focused on labeling conditions of monoclonal anti-CD20 (ex., Rituximab-Mabthera, Roche) with iodine-131, by direct radioiodination method using Chloramine-T as oxidizing agent. Labeling parameters investigated were: Radiochemical purity (RP), method of purification, incubation time, antibody mass, oxidative agent mass, stability in vitro, immunoreactivity and biological distribution performed in normal Swiss mouse. Product of high radiochemical purity was obtained with no notable difference between the methods applied. No clear evidence of direct influence of incubation time on radiochemical purity of the labeled antibody was observed. Whereas, a clear evidence of direct influence of activity on radiochemical purity of the labeled antibody was varied. After purification the labeled product presented radiochemical purity of approximately 100 %. Product of superior radiochemical yield was observed when standard condition of labeling was used. The labeled product presented variation in radiochemical purity using five different stabilizer conditions. The condition in which gentisic acid combined with freeze appears more suitable and capable of minimizing autoradiolysis of the antibody labeled with freeze appears more suitable and capable of minimizing autoradiolysis of the antibody labeled with high therapeutic activity of iodine-131. The labeled product presented low immunoreactivity when compared to the

Arid5b facilitates chondrogenesis by recruiting the histone demethylase Phf2 to Sox9-regulated genes

Science.gov (United States)

Hata, Kenji; Takashima, Rikako; Amano, Katsuhiko; Ono, Koichiro; Nakanishi, Masako; Yoshida, Michiko; Wakabayashi, Makoto; Matsuda, Akio; Maeda, Yoshinobu; Suzuki, Yutaka; Sugano, Sumio; Whitson, Robert H.; Nishimura, Riko; Yoneda, Toshiyuki

2013-11-01

Histone modification, a critical step for epigenetic regulation, is an important modulator of biological events. Sox9 is a transcription factor critical for endochondral ossification; however, proof of its epigenetic regulation remains elusive. Here we identify AT-rich interactive domain 5b (Arid5b) as a transcriptional co-regulator of Sox9. Arid5b physically associates with Sox9 and synergistically induces chondrogenesis. Growth of Arid5b-/- mice is retarded with delayed endochondral ossification. Sox9-dependent chondrogenesis is attenuated in Arid5b-deficient cells. Arid5b recruits Phf2, a histone lysine demethylase, to the promoter region of Sox9 target genes and stimulates H3K9me2 demethylation of these genes. In the promoters of chondrogenic marker genes, H3K9me2 levels are increased in Arid5b-/- chondrocytes. Finally, we show that Phf2 knockdown inhibits Sox9-induced chondrocyte differentiation. Our findings establish an epigenomic mechanism of skeletal development, whereby Arid5b promotes chondrogenesis by facilitating Phf2-mediated histone demethylation of Sox9-regulated chondrogenic gene promoters.

Site-specific conjugation and labelling of prostate antibody 7E11C5.3 (CYT-351) with technetium-99m

International Nuclear Information System (INIS)

Stalteri, M.A.; Mather, S.J.; Belinka, B.A.; Coughlin, D.J.; Chengazi, V.U.; Britton, K.E.

1997-01-01

Attachment of chelating agents to the sugar residues of antibodies for subsequent radiolabelling is an attractive approach since it may have less effect on the immunoreactivity than attachment through lysine residues, which are distributed throughout the antibody and may be present near the antigen binding site. We have attached a new hydrazide-linked chelator CYT-395 (Cytogen Corp., Princeton, N.J.) to the sugar residues of the anti-prostate monoclonal antibody 7E11C5.3 and optimised the conditions for labelling the conjugate with technetium-99m in order to compare the conjugate to 7E11C5.3 antibody labelled directly with technetium using a mercaptoethanol reduction technique. Labelling yields of 70%-90% were obtained at specific activities up to 2000 MBq/mg antibody. The stability of the technetium-labelled conjugate in plasma or to a challenge with 0.1 or 1.0 mM cysteine was similar to that of direct-labelled antibody. In nine patients with prostate cancer, the plasma clearance of the labelled conjugate followed a two-compartment model, with an average β-phase half-life of 31.4±3.9 h. The average urinary clearance at 24 h was 15.3±5.0% of the injected dose. In this group of patients there was no significant difference between the blood and urine clearance of the labelled conjugate, and the clearances of the direct-labelled antibody. (orig.). With 5 figs

sup(99m)Tc-labeled antibacterial antibody scan for the diagnosis of infective endocarditis (in rabbit)

Energy Technology Data Exchange (ETDEWEB)

Huang, J T; Tanaka, T; Wong, D W; Mishkin, F; Thadepalli, H [University of Southern California, Los Angeles (USA)

1978-01-01

The mortality of infective endocarditis is high and the results of blood cultures and clinical manifestations may be unreliable in its diagnosis. A technique has been developed using the specific antigen-antibody reaction against sup(99m)Tc-labelled antibacterial antibody. The antibody, tagged by an electrolytic method, remained very active and was not denatured since 99% of the sup(99m)Tc-antibody was able to react with antigen. The labelled antibody was injected intravenously into rabbits with experimental aortic endocarditis. The radioactivity of the infected aortic valves was about four times greater than that in the uninfected valves. A scintillation scan was able to detect the infected valves in vivo.

sup(99m)Tc-labeled antibacterial antibody scan for the diagnosis of infective endocarditis (in rabbit)

International Nuclear Information System (INIS)

Huang, J.T.; Tanaka, T.; Wong, D.W.; Mishkin, F.; Thadepalli, H.

1978-01-01

The mortality of infective endocarditis is high and the results of blood cultures and clinical manifestations may be unreliable in its diagnosis. A technique has been developed using the specific antigen-antibody reaction against sup(99m)Tc-labelled antibacterial antibody. The antibody, tagged by an electrolytic method, remained very active and was not denatured since 99% of the sup(99m)Tc-antibody was able to react with antigen. The labelled antibody was injected intravenously into rabbits with experimental aortic endocarditis. The radioactivity of the infected aortic valves was about four times greater than that in the uninfected valves. A scintillation scan was able to detect the infected valves in vivo. (U.K.)

What is wrong with radioimmunodetection and radioimmunotherapy of tumours with labelled monoclonal antibodies or with radionuclides

International Nuclear Information System (INIS)

Shukla, S.K.; Cipriani, C.; Manni, G.B.

1986-01-01

Chromatographically pure and stable anionic species of high charge density cations show higher uptake and give better melanoma images than monoclonal antibodies labeled with the same radionulcides. sup(99m)Tc-labeled antimelanoma antibody filtered for the removal of heavy colloids, hydroxides and oxides of 99m-technetium shows lower uptake in the liver and spleen. (Author)

Studies of monoclonal antibodies IOR-CEA-1 and IOR-EGF/R3 labelled with 99mTc

International Nuclear Information System (INIS)

Dias, Carla Roberta de Barros Rodrigues

2005-01-01

Nuclear Medicine is a speciality that uses radioisotopes for the diagnosis or treatment of diseases and it is considered one of the best tools among the diagnostic modalities for detection of cancer. 99m Tc is one of the main isotopes for labelling antibodies and in Nuclear Medicine in general, due to its adequate physical properties, availability and low cost. Labelled monoclonal antibodies have shown promising results for diagnosis and therapy of cancer and their use has brought great experimental and clinical advances in the field of oncology. The main clinical applications of immunoscintigraphy with monoclonal antibodies are staging and evaluation of tumoral reappearance. The antibodies employed in this work were: OIR-CEA-1, a murine monoclonal antibody that acts directly against CEA expressed in several neoplasia in particular those from the gastrointestinal tract (colorectal cancer) and IOR-EGF/R3, a murine monoclonal antibody that binds to the external domain of EGF-R and it has been used in the diagnosis of tumors of epithelial origin. The objectives of this work were the development and optimization of the reduction and purification processes, the radiolabelling techniques and quality control procedures (radiochemical, immunoreactivity and cystein challenge) and imaging studies of monoclonal antibodies OIR-CEA-1 and IOR-EGF/R3, using the simple, fast and efficient method of direct labelling of the antibody with 99m Tc. The final results was the definition of the best conditions for the preparation of lyophilized reactive kits of OIR-CEA-1 and IOR- EGF/R3 for an efficient diagnostic application in Nuclear Medicine. The most adequate conditions for the labelling of the antibodies were: 1.0 mg Ab, 29 μL MDP, 3.0 μg Sn 2+ , 1 mL of 99m Tc and 30 min. reaction time. With these conditions the labelling yield was always higher than 95% and the maximum activity of 99m Tc was about 2220 MBq (60 mCi). The evidences of the efficiency and quality of the methods here

Selective disulfide reduction for labeling and enhancement of Fab antibody fragments

International Nuclear Information System (INIS)

Kirley, Terence L.; Greis, Kenneth D.; Norman, Andrew B.

2016-01-01

Many methods have been developed for chemical labeling and enhancement of the properties of antibodies and their common fragments, including the Fab and F(ab’) 2 fragments. Somewhat selective reduction of some antibody disulfide bonds has been previously achieved, yielding antibodies and antibody fragments that can be labeled at defined sites, enhancing their utility and properties. Selective reduction of the two hinge disulfide bonds present in F(ab’) 2 fragments using mild reduction has been useful. However, such reduction is often not quantitative and results in the reduction of multiple disulfide bonds, and therefore subsequent multiple labeling or conjugation sites are neither homogenous nor stoichiometric. Here, a simple and efficient selective reduction of the single disulfide bond linking the partial heavy chain and the intact light chain which compose the Fab fragment is accomplished utilizing tris(2-carboxyethyl)phosphine (TCEP) immobilized on agarose beads. The resultant reduced cysteine residues were labeled with several cysteine-selective fluorescent reagents, as well as by cysteine-directed PEGylation. These two cysteine residues can also be re-ligated by means of a bifunctional cysteine cross-linking agent, dibromobimane, thereby both restoring a covalent linkage between the heavy and light chains at this site, far removed from the antigen binding site, and also introducing a fluorescent probe. There are many other research and clinical uses for these selectively partially reduced Fab fragments, including biotinylation, toxin and drug conjugation, and incorporation of radioisotopes, and this technique enables simple generation of very useful Fab fragment derivatives with many potential applications. - Highlights: • TCEP agarose is effective for selective reduction of a single Fab disulfide bond. • This disulfide is solvent accessible and distant from the antigen binding site. • A variety of buffers of varying pHs can be used, simplifying

Localization of tumors in vivo by scintigraphic identification of Clostridium butyricum using 131I-labelled antibodies and F(ab')2-antibody fragments

International Nuclear Information System (INIS)

Vogt, R.; Mehnert, W.H.; Schmidt, H.E.; Altenbrunn, H.J.; Akademie der Wissenschaften der DDR, Berlin-Buch. Zentralinstitut fuer Isotopen- und Strahlenforschung)

1979-01-01

Tumor-bearing mice injected with clostridial spores show enrichment and germination of the spores within the tumor. 131 I-labelled anti-Clostridium-antibodies and anti-Clostridium-F(ab') 2 -fragments were used for a possible localization of tumors in vivo by scintiscanning. The application of the antibody revealed increased radioactivity in the tumors of mice pretreated with spores as well as in animals without pretreatment. In using F(ab') 2 -fragments instead of total antibody neither the apparently unspecific increase of radioactivity in not pretreated mice nor the specific fixation of labelled F(ab') 2 -fragments to clostridial rods in the tumors of pretreated animals could be demonstrated. The results are discussed with respect to further investigation

Tau passive immunotherapy in mutant P301L mice: antibody affinity versus specificity.

Directory of Open Access Journals (Sweden)

Cristina d'Abramo

Full Text Available The use of antibodies to treat neurodegenerative diseases has undergone rapid development in the past decade. To date, immunotherapeutic approaches to Alzheimer's disease have mostly targeted amyloid beta as it is a secreted protein that can be found in plasma and CSF and is consequently accessible to circulating antibodies. Few recent publications have suggested the utility of treatment of tau pathology with monoclonal antibodies to tau. Our laboratory has begun a systematic study of different classes of tau monoclonal antibodies using mutant P301L mice. Three or seven months old mutant tau mice were inoculated weekly with tau monoclonal antibodies at a dose of 10 mg/Kg, until seven or ten months of age were reached respectively. Our data strongly support the notion that in P301L animals treated with MC1, a conformational monoclonal antibody specific for PHF-tau, the rate of development of tau pathology is effectively reduced, while injecting DA31, a high affinity tau sequence antibody, does not exert such benefit. MC1 appears superior to DA31 in overall effects, suggesting that specificity is more important than affinity in therapeutic applications. Unfortunately the survival rate of the P301L treated mice was not improved when immunizing either with MC1 or PHF1, a high affinity phospho-tau antibody previously reported to be efficacious in reducing pathological tau. These data demonstrate that passive immunotherapy in mutant tau models may be efficacious in reducing the development of tau pathology, but a great deal of work remains to be done to carefully select the tau epitopes to target.

A comparison of labelled antibody methods for the detection of virus antigens in cell monolayers

International Nuclear Information System (INIS)

Oram, J.D.; Crooks, A.J.

1979-01-01

A number of labelled antibody methods have been applied to the detection of Semliki Forest virus antigens after replication of the virus in monolayers of host cells in multi-well polystyrene plates. The importance of several reaction variables has been investigated and the sensitivity of the methods compared for different periods of virus replication. Direct assays with radio-labelled antibody (RLA) and indirect assays peroxidase-antiperoxidase complexes (PAP) were equally sensitive. Direct and indirect assays using enzyme-linked antibodies (ELA) were slightly less sensitive than the direct RLA and PAP methods but were more sensitive than the indirect RLA or fluorescent antibody (FLA) methods. Direct assays using ELA were more rapid and easier to perform than the other assay methods. (Auth.)

Development of Fluorophore-Labeled Thailanstatin Antibody-Drug Conjugates for Cellular Trafficking Studies.

Science.gov (United States)

Kulkarni, Chethana; Finley, James E; Bessire, Andrew J; Zhong, Xiaotian; Musto, Sylvia; Graziani, Edmund I

2017-04-19

As the antibody-drug conjugate (ADC) field grows increasingly important for cancer treatment, it is vital for researchers to establish a firm understanding of how ADCs function at the molecular level. To gain insight into ADC uptake, trafficking, and catabolism-processes that are critical to ADC efficacy and toxicity-imaging studies have been performed with fluorophore-labeled conjugates. However, such labels may alter the properties and behavior of the ADC under investigation. As an alternative approach, we present here the development of a "clickable" ADC bearing an azide-functionalized linker-payload (LP) poised for "click" reaction with alkyne fluorophores; the azide group represents a significantly smaller structural perturbation to the LP than most fluorophores. Notably, the clickable ADC shows excellent potency in target-expressing cells, whereas the fluorophore-labeled product ADC suffers from a significant loss of activity, underscoring the impact of the label itself on the payload. Live-cell confocal microscopy reveals robust uptake of the clickable ADC, which reacts selectively in situ with a derivatized fluorescent label. Time-course trafficking studies show greater and more rapid net internalization of the ADCs than the parent antibody. More generally, the application of chemical biology tools to the study of ADCs should improve our understanding of how ADCs are processed in biological systems.

High-efficiency astatination of antibodies using N-iodosuccinimide as the oxidising agent in labelling of N-succinimidyl 3-(trimethylstannyl)benzoate

International Nuclear Information System (INIS)

Lindegren, S.; Andersson, H.; Baeck, T.; Jacobsson, L.; Karlsson, B.; Skarnemark, G.

2001-01-01

Monoclonal antibodies C215, reactive with colorectal carcinomas, and MOv18, reactive with most of the ovarian carcinomas, were radiohalogenated with [ 211 At]astatine. The radiohalogen was conjugate coupled to antibodies via the intermediate labelling reagent N-succinimidyl-3-(trimethylstannyl)benzoate (m-MeATE) in a two-step, single-pot reaction. Optimisation of the labelling of the reagent was achieved using N-iodosuccinimide, NIS, as the oxidising agent. The yields ranged from 69-95% in the labelling of 0.1-1.0 nmole of the m-MeATE precursor. Subsequent conjugation to antibodies resulted in yields of 58±7%. In vitro binding to tumour cells showed that the immunoreactivity of both antibodies was retained after astatine labelling

{sup 68}Ga-labelled recombinant antibody variants for immuno-PET imaging of solid tumours

Energy Technology Data Exchange (ETDEWEB)

Eder, Matthias; Eisenhut, Michael [German Cancer Research Center, Radiopharmaceutical Chemistry, Heidelberg (Germany); Knackmuss, Stefan; Gall, Fabrice Le; Reusch, Uwe; Little, Melvyn [Affimed Therapeutics AG, Heidelberg (Germany); Rybin, Vladimir [European Molecular Biology Laboratory, Heidelberg (Germany); Haberkorn, Uwe; Mier, Walter [University of Heidelberg, Department of Nuclear Medicine, Heidelberg (Germany)

2010-07-15

Recombinant antibodies isolated from human antibody libraries have excellent affinities and high target specificity. As full-length IgGs are cleared inadequately slowly from the circulation, the aim of this work was to figure out which kind of recombinant antibody fragment proves to be appropriate for imaging epithelial cell adhesion molecule (EpCAM)-expressing tumours with the short-living radioisotope {sup 68}Ga. In order to combine the promising tumour targeting properties of antibodies with {sup 68}Ga, four antibody variants with the same specificity and origin only differing in molecular weight were constructed for comparison. Therefore, the binding domains of a single-chain fragment variable (scFv) isolated from a human naive antibody library were modified genetically to construct the respective full-length IgG, the tria- and diabody variants. These molecules were conjugated with the bifunctional chelating agent N,N{sup '}-bis[2-hydroxy-5-(carboxyethyl)benzyl]ethylenediamine-N,N{sup '}-diacetic acid (HBED-CC) to enable {sup 68}Ga labelling at ambient temperature and compared in biodistribution and immuno-PET imaging experiments. The antibody variants with identical specificity proved to have the correct molecular weight, high binding affinity and specificity to their antigen, EpCAM. Radiometal complexation was efficiently performed at room temperature leading to {sup 68}Ga-labelled antibodies with unchanged binding properties compared to the original antibody variants. The best targeting properties were obtained with the scFv and especially with the diabody. The triabody showed higher absolute tumour uptake but only moderate clearance from circulation. The antibody variants differed considerably in normal organ uptake, clearance from circulation and tumour accumulation. The data demonstrate the feasibility of imaging solid tumours with the {sup 68}Ga-labelled diabody format. This type of recombinant protein might be a promising carrier even for the

Solid-phase peptide quantitation assay using labeled monoclonal antibody and glutaraldehyde fixation

International Nuclear Information System (INIS)

Kasprzyk, P.G.; Cuttitta, F.; Avis, I.; Nakanishi, Y.; Treston, A.; Wong, H.; Walsh, J.H.; Mulshine, J.L.

1988-01-01

A solid-phase radioimmunoassay utilizing iodinated peptide-specific monoclonal antibody as a detection system instead of labeled peptide has been developed. Regional specific monoclonal antibodies to either gastrin-releasing peptide or gastrin were used as models to validate the general application of our modified assay. Conditions for radioactive labeling of the monoclonal antibody were determined to minimize oxidant damage, which compromises the sensitivity of other reported peptide quantitation assays. Pretreatment of 96-well polyvinyl chloride test plates with a 5% glutaraldehyde solution resulted in consistent retention of sufficient target peptide on the solid-phase matrix to allow precise quantitation. This quantitative method is completed within 1 h of peptide solid phasing. Pretreatment of assay plates with glutaraldehyde increased binding of target peptide and maximized antibody binding by optimizing antigen presentation. The hypothesis that glutaraldehyde affects both peptide binding to the plate and orientation of the peptide was confirmed by analysis of several peptide analogs. These studies indicate that peptide binding was mediated through a free amino group leaving the carboxy-terminal portion of the target peptide accessible for antibody binding. It was observed that the length of the peptide also affects the amount of monoclonal antibody that will bind. Under the optimal conditions, results from quantitation of gastrin-releasing peptide in relevant samples agree well with those from previously reported techniques. Thus, we report here a modified microplate assay which may be generally applied for the rapid and sensitive quantitation of peptide hormones

Targetted localisation and imaging of a murine lymphoma using 131I-labelled monoclonal antibody

International Nuclear Information System (INIS)

Subbiah, Krishnan; Rayala, Suresh Kumar; Ananthanarayanan, Meenakshi; Thangarajan, Rajkumar

2001-01-01

In vivo tumor targetting with radiolabelled monoclonal antibodies is a promising approach for the diagnosis and therapy of tumors. A specific monoclonal antibody (mAb), DLAB was generated to the Dalton's lymphoma associated antigen (DLAA) from Haemophilus paragallinarum -induced spontaneous fusion. In order to study the tumor localisation and biodistribution properties of the monoclonal antibody, scintigraphic studies were performed using the radiolabelled DLAB. 131I -labelled DLAB was administered intravenously into Swiss mice bearing Dalton's lymphoma and external scintiscanning was performed at different time intervals. Clear tumor images were obtained which revealed selective and specific uptake of radiolabel and the results were compared with biodistribution data. The radioiodinated monoclonal antibody showed fast tumor uptake which increased significantly to 14.6% injected dose (ID)/g at 12 hr post-injection. Enhanced blood clearance of radioactivity resulted in higher tumor/blood ratio of 5.96 at 48 hr. 131I -labelled DLAB resulted in selective and enhanced uptake of the radioactivity by the tumor compared to the non-specific antibody and the results suggest the potential use of spontaneous fusion for producing specific monoclonal antibodies for tumor detection and therapy. (author)

Investigation of high spin structure of N ∼ 28 nuclei with PHF model

International Nuclear Information System (INIS)

Naik, Z.

2016-01-01

Nucleus in 50 mass shows verity of high spin phenomena. Some of them are K-Isomer, Band termination, States Beyond Band termination, Superdeformed Structure, Shape co-existence and many more. Some of these phenomena with Projected Hartree-Fock (PHF) model are addressed and the microscopic structure associate with them is discussed

Complete assignment of the methionyl carbonyl carbon resonance in switch variant anti-dansyl antibodies labeled with [1-13C]methionine

International Nuclear Information System (INIS)

Kato, Koichi; Matsunaga, C.; Igarashi, Takako; Kim, Hahyung; Odaka, Asano; Shimada, Ichio; Arata, Yoji

1991-01-01

A 13 C NMR study is reported of switch variant anti-dansyl antibodies developed by Dangl et al. who had used the fluorescence-activated cell sorter to select and clone these variants. These switch variant antibodies possess the identical V H , V L , and C L domains in conjunction with different heavy chain constant regions. In the present study, switch variant antibodies of IgG1, IgG2a, and IgG2b subclasses were used along with a short-chain IgG2a antibody, in which the entire C H 1 domain is deleted. The switch variant antibodies were specifically labeled with [1- 13 C]methionine by growing hybridoma cells in serum-free medium. Assignments of all the methionyl carbonyl carbon resonances have been completed by using the intact antibodies along with their fragments and recombined proteins in which either heavy or light chain is labeled. A double labeling method has played a crucial role in the process of the spectral assignments. The strategy used for the assignments has been described in detail. In incorporating 15 N-labeled amino acids into the antibodies for the double labeling, isotope dilution caused a serious problem except in the cases of [α- 15 N]lysine and [ 15 N]threonine, both of which cannot become the substrate of transaminases. It was found that β-chloro-L-alanine is most effective in suppressing the isotope scrambling. So far, spectral assignments by the double labeling method have been possible with 15 N-labeled Ala, His, Ile, Lys, Met, Ser, Thr, Tyr, and Val. On the basis of the results of the present 13 C study, possible use of the assigned carbonyl carbon resonances for the elucidation of the structure-function relationship in the antibody system has been briefly discussed

Study of the viability of technetium-99m labeling of whole antimyosin antibody and its fragment: development of radiopharmaceutical for cardiac survey

International Nuclear Information System (INIS)

Carvalho, Guilherme Luiz de Castro

2007-01-01

In the acute myocardium infarction, the myocytes cell membrane loses its integrity, allowing the influx of extracellular macromolecules such as circulating antibody into the damaged cell. The use of the specific antibodies against cardiac myosin labeled with 99m Tc allows to determine the localization and extension of myocardial infarction. The purpose of this work was to study the viability of labeling of the antimyosin monoclonal antibody and its fragment F(ab')2 with 99m Tc. Because of the high cost of antimyosin antibody, others antibodies were used to optimize the methodology and the best condition was used for antimyosin antibody. The intact antibody was cleaved by pepsin to produce F(ab') 2 fragment. The F(ab') 2 and the intact antibody were reduced by treatment with Dithiothreitol (DTT) and 2-Mercaptoethanol (2-ME) and labeled with 99m Tc by direct method. Different concentrations of reductant, mixing conditions and incubation times were studied. In the standard condition, incubation at molar ratio 1:1000 (antibody:reducing agent) at room temperature for 30 minutes with continuous rotation (850 rpm), 13.28 - SH groups were formed per molecule. It was studied the influence of p H, of the concentration of stannous chloride (Sn 2+ ) and incubation time in the labeling condition. The better radiochemical yield (90.06 +- 1.53%) was obtained using 2.5 μg of Sn 2+ in p H 4.5 for 60 minutes. The labeling of the fragment F(ab') 2 did not present satisfactory results because of the low yield of the digestion. After purification by PD-10, the biodistribution study was performed and showed that the intact antimyosin antibody labeled with 99m Tc presented fast kinetic compatible with the biodistribution of an intact antibody labeled with 99m Tc. Scintigraphy image of the animal with myocardial infarction was obtained and compared with the image of a normal animal. The studies allow to conclude that the use of fragment F(ab') 2 are not viable, but the use of the labeled

Immunoscintigraphy with 99Tc-labelled monoclonal anti granulocyte antibodies in patients with inflammatory bowel disease

International Nuclear Information System (INIS)

Klisarova, A.; Tranulov, G.

1996-01-01

Antigranulocyte immunoscintigraphy with 99 Tc-labelled monoclonal antigranolocyte antibodies (MAb BW 250/83, Granulozyt) was carried out in ten patients with symptoms of inflammatory bowel disease to exclude or confirm the presence of an inflammatory process. A slow iv infusion of 740 MBq of the antibodies was performed 40 minutes after labelling. A whole-body scan was done at hours 4 and 24 post injection. In four patients planar scintigraphy of abdominal region only was also performed for better visualization of the pathological findings. Immunoscintigraphy provided evidence of an inflammatory bowel process in 8 cases (true positive), and excluded the diagnosis in one case (true negative). There was one false negative result.The study shows that immunoscintigraphy with 99 Tc-labelled antibodies (Granulozyt) is an easily performed procedure, with high specificity for diagnosing inflammatory bowel disease and can be carried out as a routine practice in nuclear medicine. 7 refs., 1 tab., 4 figs. (author)

Effect of unlabelled monoclonal antibody (MoAb) on biodistribution of /sup 111/Indium labelled (MoAb)

Energy Technology Data Exchange (ETDEWEB)

Lamki, L M; Murray, J L; Rosenblum, M G; Patt, Y Z; Babaian, Richard; Unger, M W

1988-08-01

We have evaluated immunoscintigraphy in cancer patients using four /sup 111/In-labelled murine monoclonal antibodies (MoAb): 96.5 (anti-P97 of melanoma), ZME-018 (anti-high molecular weight antibody of melanoma), ZCE-025 (anti-CEA for colon cancer) and PAY-276 (anti-prostatic acid phosphatase for prostatic cancer). The effect of increasing the doses of unlabelled MoAb (co-infused with 1 mg labelled MoAb) on the relative body distribution of each labelled MoAb was assessed. Localization in the liver decreased significantly in all cases, with increasing MoAb dose, except for ZME-018. Localization in other organs increased significantly as the liver activity decreased. The spleen activity, however, fell in the case of MoAb ZME-018. Blood-pool activity increased with MoAb dose in all four MoAbs. These findings correlated with the rise in the detection rate of metastases, the plasma half-life, and other pharmacokinetic parameters. However, the dose level at which this correlation occurred varied with each antibody. These data demonstrate the co-infusion of unlabelled MoAb with /sup 111/In-labelled MoAb could alter the organ distribution, pharmacokinetics and tumour uptake in a favourable manner, though the degree to which this occurs depends on the antibody in question.

Labeling an anti-CD20 monoclonal antibody with 90Y

International Nuclear Information System (INIS)

Perera Pintado, Alejandro; Leyva Montaña, René; Prats Capote, Anaís; Góngora Bravo, Magdiel; Alberti Ramírez, Alejandro; León, Mariela; Hernández González, Ignacio; Dorvignit, Denise

2016-01-01

Lymphomas are among the 10 leading causes of death, both in Cuba and in the world, with an increasing incidence in recent years. Follicular lymphoma low-grade (indolent) is one of the most common in the Western world, representing 1/3 of all non-Hodgkin lymphomas (NHL). More than 90% of patients present with disseminated disease at diagnosis and generally have a slow evolution and good response to conventional treatment; but radically changed its forecast to relapse, resistance to therapeutic and histologic transformation can occur. The monoclonal antibody therapy has been a promising therapeutic. In this respect CD20 antigen it has been considered one of the most attractive targets in the therapy of follicular B cell lymphoma This is expressed in more than 90% of cases, while not present in stem cells and lines progenitors. Despite the success of immunotherapy, the relapse rate is still considerable. In order to increase the cytotoxic potential of immunotherapy, marked with beta emitting radionuclides alpha particles or monoclonal antibodies are used today. Despite encouraging results in patients with non-Hodgkin lymphomas refractory to other treatments, the extremely high costs of these commercial radiopharmaceuticals have greatly limited its application, even in the first world. A sustainable alternative is the marking of other anti-CD20 monoclonal antibodies, so researchers from several countries have concentrated their efforts on rituximaby other similar antibodies labeled with therapeutic radionuclides, as a possible cost-effectively to more problem. Today in Cuba it has an electrolytic generator 90 Sr- 90 Y Isotope Center, which ensures the availability of the radionuclide. In addition, the chimeric MAb rituximab is applied as part of the therapy of NHL in its health system and, recently, the Center for Molecular Immunology has obtained a chimeric monoclonal anti-CD20 antibody biosimilar rituximab, which is in phase clinical trial; which opens prospects for

Labeling of monoclonal antibodies with a 67Ga-phenolic aminocarboxylic acid chelate. Part II. Comparison of immunoreactivity and biodistribution of monoclonal antibodies labeled with the 67Ga-chelate or with 131I.

Science.gov (United States)

Matzku, S; Schuhmacher, J; Kirchgessner, H; Brüggen, J

1986-01-01

Coupling of the 67Ga-P-EDDHA chelate via carbodiimide to the anti-melanoma monoclonal antibody (Mab) M.2.9.4 resulted in a low degree of oligomerization, but a considerable degree of intra-molecular (inter-chain) cross-linking. However, this did not impair immunoreactivity, nor did the half-life in vivo differ substantially from that of 131I-M.2.9.4. Biodistribution analysis in normal mice showed Ga:I ratios near 1 in the blood and other tissues not involved in degradation and label excretion. In tissues of the reticulo-endothelial system (RES) and the kidneys, Ga:I ratios up to 2.51 were reached within 4 days of administration. In antigen-positive MeWo tumor tissue, retention of 67Ga also excreted that of 131I, so that tumor; organ ratios (except tumor:liver) were superior for the 67Ga-labeled MAb. It is concluded that the method of coupling pre-established 67Ga-P-EDDHA chelate to antibody results in a functionally intact tracer molecule, whose persistence in vivo is not significantly impaired. The major difference to I-labeled MAbs may be a prolonged retention of Ga in tissues (cells) physiologically involved in antibody catabolism.

ECT with /sup 123/I-labeled fragments of anti-CEA monoclonal antibodies in colo-rectal cancer

International Nuclear Information System (INIS)

Bischof-Delaloye, A.; Delaloye, B.

1986-01-01

The recent progress of tumor localization with labelled antibodies can be attributed to three techniques: 1) use of I-123 as a label; 2) fragmentation of antibodies; 3) tomographic recording and evaluation of patient radiation data. Under these conditions the method yields good sensitivity and specifity indexes (15/16 for primary tumors and local recurrences, 7/10 for metastasis). A strictly prospective study, however, remains mandatory in order to assess the clinical value of this method

Tetrafluorophenolate of HBED-CC: a versatile conjugation agent for 68Ga-labeled small recombinant antibodies

International Nuclear Information System (INIS)

Eder, Matthias; Waengler, Bjoern; Eisenhut, Michael; Knackmuss, Stefan; LeGall, Fabrice; Little, Melvyn; Haberkorn, Uwe; Mier, Walter

2008-01-01

The success of 68 Ga-labeled peptides for positron emission tomography of neuroendocrine tumors is mainly depending on the complex chemistry of this radioisotope. 1,4,7,10-Tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), the chelator of choice has however limitations if its application is expanded to heat-sensitive proteins. Recombinant antibodies like single chain Fv or diabodies belong to this class of proteins. They are suited to provide imaging contrast despite the short-lived 68 Ga because of their rapid blood clearances and nanomolar affinities. The heterobifunctional agent N,N'-bis[2-hydroxy-5-(carboxyethyl)benzyl]ethylenediamine-N,N'-diacetic acid (HBED-CC) was chosen as an alternative ligand because this agent is complexing [ 68 Ga]Ga 3+ much faster than DOTA at ambient temperatures. A versatile technology for HBED-CC conjugation of proteins and 68 Ga-labeling has been developed. This included HBED-CC-tetrafluorophenol (TFP) ester synthesis, coupling to the antibody at various pH and complexation reactions performed in 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) buffer under different conditions. The synthesis of the monoreactive 2,3,5,6-tetrafluorophenolate of HBED-CC at a carboxyl group not participating in complex formation used [Fe(HBED-CC)] - for ester formation. The removal of Fe 3+ from purified (HBED-CC)TFP ester was achieved with RP 18 cartridge technology. The conjugation chemistry was performed with mAb425 which binds to the epidermal growth factor receptor (EGFR). This protein was used for optimizing purposes only. The influence of complexation parameters like temperature, pH, reaction time, and HBED-CC/antibody ratio on the biological activity of this model antibody was investigated. Furthermore, the outcome of this labeling procedure on the biological activity of a recombinant diabody (50 kDa) was studied. It is known that small HBED-CC/antibody ratios are prerequisites for minimal interference of labels with antigen

Complete assignment of the methionyl carbonyl carbon resonance in switch variant anti-dansyl antibodies labeled with (1- sup 13 C)methionine

Energy Technology Data Exchange (ETDEWEB)

Kato, Koichi; Matsunaga, C.; Igarashi, Takako; Kim, Hahyung; Odaka, Asano; Shimada, Ichio; Arata, Yoji (Univ. of Tokyo, Hongo (Japan))

1991-01-01

A {sup 13}C NMR study is reported of switch variant anti-dansyl antibodies developed by Dangl et al. who had used the fluorescence-activated cell sorter to select and clone these variants. These switch variant antibodies possess the identical V{sub H}, V{sub L}, and C{sub L} domains in conjunction with different heavy chain constant regions. In the present study, switch variant antibodies of IgG1, IgG2a, and IgG2b subclasses were used along with a short-chain IgG2a antibody, in which the entire C{sub H}1 domain is deleted. The switch variant antibodies were specifically labeled with (1-{sup 13}C)methionine by growing hybridoma cells in serum-free medium. Assignments of all the methionyl carbonyl carbon resonances have been completed by using the intact antibodies along with their fragments and recombined proteins in which either heavy or light chain is labeled. A double labeling method has played a crucial role in the process of the spectral assignments. The strategy used for the assignments has been described in detail. In incorporating {sup 15}N-labeled amino acids into the antibodies for the double labeling, isotope dilution caused a serious problem except in the cases of ({alpha}-{sup 15}N)lysine and ({sup 15}N)threonine, both of which cannot become the substrate of transaminases. It was found that {beta}-chloro-L-alanine is most effective in suppressing the isotope scrambling. So far, spectral assignments by the double labeling method have been possible with {sup 15}N-labeled Ala, His, Ile, Lys, Met, Ser, Thr, Tyr, and Val. On the basis of the results of the present {sup 13}C study, possible use of the assigned carbonyl carbon resonances for the elucidation of the structure-function relationship in the antibody system has been briefly discussed.

Labeling of monoclonal antibodies with a 67Ga phenolic aminocarboxylic acid chelate. Pt. 2

International Nuclear Information System (INIS)

Matzku, S.; Schuhmacher, J.; Kirchgessner, H.; Brueggen, J.

1986-01-01

Coupling of the 67 Ga-P-EDDHA chelate via carbodiimide to the anti-melanoma monoclonal antibody (MAb) M.2.9.4 resulted in a low degree of oligomerization, but a considerable degree of intra-molecular (inter-chain) cross-linking. However, this did not impair immunoreactivity, nor did the half-life in vivo differ substantially from that of 131 I-M.2.9.4. Biodistribution analysis in normal mice showed Ga:I ratios near 1 in the blood and other tissues not involved in degradation and label excretion. In tissues of the reticulo-endothelial system (RES) and the kidneys, Ga:I ratios up to 2.51 were reached within 4 days of administration. In antigen-positive MeWo tumor tissue, retention of 67 Ga also exceeded that of 131 I, so that tumor : organ ratios (except tumor : liver) were superior for the 67 Ga-labeled MAb. It is concluded that the method of coupling pre-established 67 Ga-P-EDDHA chelate to antibody, results in a functionally intact tracer molecule, whose persistence in vivo is not significantly impaired. The major difference to I-labeled MAbs may be prolonged retention of Ga in tissues (cells) physiologically involved in antibody catabolism. (orig.)

PIP2 epigenetically represses rRNA genes transcription interacting with PHF8

Czech Academy of Sciences Publication Activity Database

Uličná, Lívia; Kalendová, Alžběta; Kalasová, Ilona; Vacík, Tomáš; Hozák, Pavel

2018-01-01

Roč. 1863, č. 3 (2018), s. 266-275 ISSN 1388-1981 R&D Projects: GA ČR GA15-08738S; GA MŠk(CZ) ED1.1.00/02.0109; GA MŠk(CZ) LM2015062 Institutional support: RVO:68378050 Keywords : pip2 * phf8 * rDNA transcription * H3K9me2 * Nucleus Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.547, year: 2016

Localization, kinetics and metabolism of labelled monoclonal antibodies on a cellular level

International Nuclear Information System (INIS)

Steinstraesser, A.; Kuhlmann, L.; Zimmer, M.; Schwarz, A.

1988-01-01

In order to gain insight into the mechanisms, the localization, kinetics and metabolism of preparations labelled with 131 J and 111 In were examined on a cellular level. Micro-autoradiography for histological assessment of the storage tissue in the organs was complemented by cytological examination methods for assessing the extent of internalisation of the antibodies, and the metabolism of the antibodies in the cytosol fraction could be followed up by chromatography. One of the major results is that even with the complete antibody, accumulation in the liver cells proceeds very rapidly and protein degradation is practically completed within twenty-four hours. In the tumor, however, internalisation plays a minor part (about 80 p.c. of the antibodies remain bound to the membrane). Rapid accumulation of the antibodies by the tubulus epithelium of the kidney causes the intensive image of the renal scintiscan. (orig./MG) [de

Severe persistent pulmonary hypertension of the newborn and dysmorphic features in neonate with a deletion involving TWIST1 and PHF14: a case report.

Science.gov (United States)

Schinagl, Carina; Melum, Guro Reinholt; Rødningen, Olaug Kristin; Bjørgo, Kathrine; Andresen, Jannicke Hanne

2017-08-17

Persistent pulmonary hypertension is a well-known disease of the newborn that in most cases responds well to treatment with nitric oxide and treatment of any underlying causes. Genetic causes of persistent pulmonary hypertension of the newborn are rare. The TWIST1 gene is involved in morphogenetics, and deletions are known to cause Saethre-Chotzen syndrome. Deletions of PHF14 have never been reported in neonates, but animal studies have shown a link between severe defects in lung development and deletions of this gene. There have not, to the best of our knowledge, been any publications of a link between the genes TWIST1 and PHF14 and persistent pulmonary hypertension of the newborn, making this a novel finding. We describe a white male neonate born at term to non-consanguineous white parents; he presented with dysmorphic features and a therapy-refractory persistent pulmonary hypertension. Array-based comparative genomic hybridization revealed the presence of a 14.7 Mb interstitial deletion on chromosome 7, encompassing the genes TWIST1 and PHF14. The TWIST1 gene can explain our patient's dysmorphic features. His severe persistent pulmonary hypertension has, however, not been described before in conjunction with the TWIST1 gene, but could be explained by involvement of PHF14, consistent with findings in animal experiments showing lethal respiratory failure with depletion of PHF14. These findings are novel and of importance for the clinical management and diagnostic workup of neonates with severe persistent pulmonary hypertension of the newborn and dysmorphic features.

Technetium-99 labelling of DD-3B6/22 antifibrin monoclonal antibody fragmented Fab' for thrombus imaging

International Nuclear Information System (INIS)

Lee, F-T.; Boniface, G.R.; Lambrecht, R.M.; Rylatt, D.B.; Bundesen, P.G.

1993-01-01

The antifibrin DD-3B6/22 monoclonal antibody Fab' fragment, a murine immunoglobulin, IgG3, has been labelled with technetium-99m ( 99mTc ) via a transchelation reaction, to specific activity in excess of 30 mCi/mg protein. The radiolabelling of Fab' was dependent on time, temperature, pH, antibody concentrations and nature intermediary transchelation complex used. The resultant radioconjugate was stable in vitro and in vivo. Blood clearance of 99m Tc-Fab' in rat followed two compartment kinetics with the half time of the fast phase being 0.5 h. The main route of excretion was via the kidneys with little uptake indicated by other tissues. The results suggest that the inherent specificity of the antibody, small molecular size, rapid plasma clearance, high specific radioactivity, together with the physical properties of the 99m Tc label, combine to make this labelled monoclonal antibody (MoAb), potentially suitable as a radiopharmaceutical for the scintigraphic detection of thrombi in humans. 17 refs., 3 tabs., 5 figs

Tumor scintigraphy by the method for subtracting the initial image with technetium-99m labeled antibody

International Nuclear Information System (INIS)

Karube, Yoshiharu; Katsuno, Kentaro; Ito, Sanae; Matsunaga, Kazuhisa; Takata, Jiro; Kuroki, Masahide; Murakami, Masaaki; Matsuoka, Yuji

1999-01-01

The method for subtracting the initial image from the localization image was evaluated for radioimmunoscintigraphy of tumors with technetium-99m (Tc-99m) labeled antibodies. Monoclonal antibodies were parental mouse and mouse-human chimeric antibodies to carcinoembryonic antigen (CEA), designated F11-39 and ChF11-39, respectively, both of which have been found to discriminate CEA in tumor tissues from the CEA-related antigens. After reduction of the intrinsic disulfide bonds, these antibodies were labeled with Tc-99m. In vivo studies were performed on athymic nude mice bearing the human CEA-producing gastric carcinoma xenografts. Though biodistribution results showed selective and progressive accumulation of Tc-99m labeled antibodies at the tumor site, high radioactivity in blood was inappropriate for scintigraphic visualization of the tumors within a few hours. We examined the subtraction of the initial Tc-99m image from the Tc-99m localization image after a few hours. Subtracted images of the same count reflected the in vivo behavior of the Tc-99m radioactivity. The subtracted scintigrams revealed excellent tumor images with no significant extrarenal background. Visualization of the tumor site was dependent on antigen-specific binding and nonspecific exudation. These results demonstrate that a method of subtraction of the initial image may serve as a potentially useful diagnostic method for an abnormal site for agents with a low pharmacokinetic value. (author)

Reduced 99mTc labelled NCA-95/CEA-antibody uptake in liver due to gentle antibody reconstitution

International Nuclear Information System (INIS)

Reske, S.N.; Buell, U.

1990-01-01

The influence of reconstituting a murine monoclonal IgG 1 antibody kit with pertechnetate Tc99m on antibody distribution in the liver, spleen and sternal bone marrow of patients was examined. The 99m Tc-labelled antibody used is directed against non-specific cross-reacting antigen (NCA-95) and carcinoembryonic antigen (CEA) and has been successfully applied for imaging tissue inflammation and bone marrow scanning. Radioactivity uptake was determined in the liver, spleen, bone marrow and a precordial background region in a consecutive series of 25 patients, examined with an antibody preparation, routinely radiolabelled according to the manufacturer's recommendations and in 14 patients, in whom the antibody was reconstituted with special care, avoiding bubble formation and dropping of buffer into the antibody-containing vial. Gentle compared with routine antibody reconstitution caused a highly significant reduction of the antibody uptake in the liver, as determined by count densities, normalized to injected dose and acquisition time (13.2±5.5 vs 20.1±6.0 cpm per pixel, anti x±SD, P=0.008). The liver to background ratio was reduced from 3.4±1.4 to 1.9±0.5 (P<0.001). Spleen, sternal bone marrow and precordial background count rates were not significantly affected. These results clearly demonstrate that gentle antibody reconstitution can decrease non-specific antibody uptake in the liver by 34%±6.4% (anti x±SEM). Thus, scan quality is improved, and the potential deleterious camouflage of underlying structures is avoided. (orig.)

Synthesis of indium-labeled antibody-chelate conjugates for radioassays

Energy Technology Data Exchange (ETDEWEB)

Gokce, A; Nakamura, R M; Tubis, M; Wolf, W

1982-01-01

A method has been developed to achieve rapid and reproducible complexation of indium to transferrin at pH 7.4. The system consists of nitrilotriacetic acid (NTA) as the intermediate carrier ligand, whose function is to allow the /sup 113/m In ion, in a solution in Tris buffer, pH 7.4, to be transferred rapidly to the specific binding sites on transferrin. Just as in the case of iron, this complexation requires the presence of a synergistic ion such as bicarbonate. The present system can be used to allow the binding of /sup 113/mIn to transferrin when coupled to an antibody. This method has been tested by studying the conjugation of an antibody, the IgG fraction of goat anti-rabbit-IgG, with either transferrin or desferoxamine, using glutaraldehyde as the coupling agent. Optimization in terms of total protein concentration and glutaraldehyde levels lead to products where the specific metal binding capacity of the transferrin moiety remains unchanged, and where the antibody retains 70% of its antigenic activity. The present system can be considered an extension of the ELISA techniques and can be used to determine, by a terminal /sup 113/mIn labeling technique, the level of specific binding of an antibody to its antigen.

Labeling of monoclonal antibodies with a 67Ga-phenolic aminocarboxylic acid chelate. Part I. Chemistry and labeling technique.

Science.gov (United States)

Schuhmacher, J; Matys, R; Hauser, H; Maier-Borst, W; Matzku, S

1986-01-01

As a chelating agent for labeling antibodies (Abs) with metallic radionuclides, a propionic acid substituted ethylenediamine N,N'-di-[(o-hydroxyphenyl) acetic acid] (P-EDDHA), which tightly complexes 67Ga, was synthesized. The 67Ga-P-EDDHA chelate was coupled in aqueous solution to IgG at a molar ratio of 1:1 via carbodiimide. The average coupling yield was 15%. A specific activity of 4 mCi/mg IgG could be obtained with commercially supplied 67Ga. In vitro stability was evaluated in human serum at 37 degrees C and showed a half-life of about 120 h for the release of 67Ga from the labeled Ab during the initial phase of incubation. This in vitro halflife is similar to that measured for 111In-DTPA labeled Abs. Because of the high stability of the 67Ga-P-EDDHA chelate, the in vivo formation of radioactive labeled transferrin by transchelation, as described for 111In-DTPA labeled Abs, should, however, be reduced by this labeling technique.

PIP2 epigenetically represses rRNA genes transcription interacting with PHF8

Czech Academy of Sciences Publication Activity Database

Uličná, Lívia; Kalendová, Alžběta; Kalasová, Ilona; Vacík, Tomáš; Hozák, Pavel

2018-01-01

Roč. 1863, č. 3 (2018), s. 266-275 ISSN 1388-1981 R&D Projects: GA ČR GA15-08738S; GA MŠk(CZ) ED1.1.00/02.0109; GA MŠk(CZ) LM2015062 Institutional support: RVO:68378050 Keywords : PIP2 * PHF8 * rDNA transcription * H3K9me2 * Nucleus Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Biochemistry and molecular biology Impact factor: 5.547, year: 2016

Comparison of SPECT and whole-body planar imaging in radioimmunoscintigraphy with Tc-labeled antibodies

International Nuclear Information System (INIS)

Lacic, K.; Bokulic, T.; Lukac, J.; Dakovic, N.; Kusic, Z.

1994-01-01

The authors of some recent clinical studies suggested 20-24 hours SPECT imaging as a mandatory procedure in radioimmunoscintigraphy with Tc-labeled antibodies. The aim of our study was to compare whole-body (WB) planar imaging versus SPECT as well as 4-6 hours SPECT to 20-24 hours one. For this purpose we analyzed 33 lesions in 12 postsurgical patients with colorectal carcinoma. Each patient received intravenously 0.5-1.0 mg anti-CEA BW 431/26 murine monoclonal IgG-antibodies labeled with Tc-99m (814-1110 MBq). WB and SPECT imaging were performed at 4-6 and 20-24 hours post infusion. 20-24 hours WB scan imaged more 'hot' and less 'cold' lesions than 4-6 hours one. SPECT scan showed significantly more lesions than WB scan. 20-24 hours SPECT scan detected more 'hot' lesions than 4-6 hours SPECT. At the same time the number of 'cold' lesions decreased in 20-24 hours SPECT in comparison to 4-6 hours one. As a conclusion we can say that our results suggest a superiority of SPECT imaging in comparison to WB scan. Except that, in our opinion performing of a 20-24 hours SPECT scan in radioimmunoscintigraphy with Tc-labeled antibodies should be mandatory. (author)

Comparison of SPECT and whole-body planar imaging in radioimmunoscintigraphy with Tc-labeled antibodies

Energy Technology Data Exchange (ETDEWEB)

Lacic, K; Bokulic, T; Lukac, J; Dakovic, N; Kusic, Z [Clinical Hospital Sestre Milosrdnice, Zagreb (Croatia). Dept. of Oncology and Nuclear Medicine

1994-10-01

The authors of some recent clinical studies suggested 20-24 hours SPECT imaging as a mandatory procedure in radioimmunoscintigraphy with Tc-labeled antibodies. The aim of our study was to compare whole-body (WB) planar imaging versus SPECT as well as 4-6 hours SPECT to 20-24 hours one. For this purpose we analyzed 33 lesions in 12 postsurgical patients with colorectal carcinoma. Each patient received intravenously 0.5-1.0 mg anti-CEA BW 431/26 murine monoclonal IgG-antibodies labeled with Tc-99m (814-1110 MBq). WB and SPECT imaging were performed at 4-6 and 20-24 hours post infusion. 20-24 hours WB scan imaged more `hot` and less `cold` lesions than 4-6 hours one. SPECT scan showed significantly more lesions than WB scan. 20-24 hours SPECT scan detected more `hot` lesions than 4-6 hours SPECT. At the same time the number of `cold` lesions decreased in 20-24 hours SPECT in comparison to 4-6 hours one. As a conclusion we can say that our results suggest a superiority of SPECT imaging in comparison to WB scan. Except that, in our opinion performing of a 20-24 hours SPECT scan in radioimmunoscintigraphy with Tc-labeled antibodies should be mandatory. (author).

Preparation of 125I-labeled monoclonal antibody of bladder neoplasm using lactoperoxidase

International Nuclear Information System (INIS)

Li Huaifen; Niu Huisheng; Yuan Mingyue; Huang Yongzhi

1994-01-01

125 I-labelled monoclonal antibody of bladder neoplasm ( 125 I-L 4 B 4 ) is prepared using lactoperoxidase. The in-vivo radioactive distribution of 125 I-L 4 B 4 in bare mice shows that 125 I-L 4 B 4 concentrates in the tumour

Radioimmunoscintigraphy of colorectal carcinoma using technetium-99m-labeled, totally human monoclonal antibody 88BV59H21-2.

Science.gov (United States)

Gulec, S A; Serafini, A N; Moffat, F L; Vargas-Cuba, R D; Sfakianakis, G N; Franceschi, D; Crichton, V Z; Subramanian, R; Klein, J L; De Jager, R L

1995-12-01

Radioimmunoscintigraphy (RIS) using human monoclonal antibodies offers the important clinical advantage of repeated imaging over murine monoclonal antibodies by eliminating the cross-species antibody response. This article reports a Phase I-II clinical trial with Tc-99m-labeled, totally human monoclonal antibody 88BV59H21-2 in patients with colorectal carcinoma. The study population consisted of 34 patients with colorectal cancer (20 men and 14 women; age range, 44-81 years). Patients were administered 5-10 mg antibody labeled with 21-41 mCi Tc-99m by the i.v. route and imaged at 3-10 and 16-24 h after infusion using planar and single-photon emission computed tomographic (CT) techniques. Pathological confirmation was obtained in 25 patients who underwent surgery. Human antihuman antibody (HAHA) titers were checked prior to and 1 and 3 months after the infusion. RIS with Tc-99m-labeled 88BV59H21-2 revealed a better detection rate in the abdomen-pelvis region compared with axial CT. The combined use of both modalities increased the sensitivity in both the liver and abdomen-pelvis regions. Ten patients developed mild adverse reactions (chills and fever). No HAHA response was detected in this series. Tc-99m-labeled human monoclonal antibody 88BV59H21-2 RIS shows promise as a useful diagnostic modality in patients with colorectal cancer. RIS alone or in combination with CT is more sensitive than CT in detecting tumor within the abdomen and pelvis. Repeated RIS studies may be possible, due to the lack of a HAHA response.

Radiobromination of humanized anti-HER2 monoclonal antibody trastuzumab using N-succinimidyl 5-bromo-3-pyridinecarboxylate, a potential label for immunoPET

Energy Technology Data Exchange (ETDEWEB)

Mume, Eskender [Organic Chemistry, Department of Chemistry, Uppsala University, S-751 24 Uppsala (Sweden); Orlova, Anna [Affibody AB, S-161 02 Bromma (Sweden); Malmstroem, Per-Uno [Division of Urology, Department of Surgical Sciences, Uppsala University, S-751 85 Uppsala (Sweden); Lundqvist, Hans [Unit of Biomedical Radiation Sciences, Rudbeck Laboratory, Uppsala University, S-751 85 Uppsala (Sweden); Sjoeberg, Stefan [Organic Chemistry, Department of Chemistry, Uppsala University, S-751 24 Uppsala (Sweden); Tolmachev, Vladimir [Unit of Biomedical Radiation Sciences, Rudbeck Laboratory, Uppsala University, S-751 85 Uppsala (Sweden)]. E-mail: vladimir.tolmachev@bms.uu.se

2005-08-01

Combining the specificity of radioimmunoscintigraphy and the high sensitivity of PET in an in vivo detection technique could improve the quality of nuclear diagnostics. Positron-emitting nuclide {sup 76}Br (T {sub 1/2}=16.2 h) might be a possible candidate for labeling monoclonal antibodies (mAbs) and their fragments, provided that the appropriate labeling chemistry has been established. For internalizing antibodies, such as the humanized anti-HER2 monoclonal antibody, trastuzumab, radiobromine label should be residualizing, i.e., ensuring that radiocatabolites are trapped intracellularly after the proteolytic degradation of antibody. This study evaluated the chemistry of indirect radiobromination of trastuzumab using N-succinimidyl 5-(tributylstannyl)-3-pyridinecarboxylate. Literature data indicated that the use of this method provided residualizing properties for iodine and astatine labels on some antibodies. An optimized 'one-pot' procedure produced an overall labeling efficiency of 45.5{+-}1.2% over 15 min. The bromine label was stable under physiological and denaturing conditions. The labeled trastuzumab retained its capacity to bind specifically to HER2-expressing SKOV-3 ovarian carcinoma cells in vitro (immunoreactivity more than 75%). However, in vitro cell test did not demonstrate that the radiobromination of trastuzumab using N-succinimidyl 5-bromo-3-pyridinecarboxylate improves cellular retention of radioactivity in comparison with the use of N-succinimidyl 4-bromobenzoate.

Nuclear medicine: Monoclonal antibodies

International Nuclear Information System (INIS)

Endo, K.; Sakahara, H.; Koizumi, M.; Kawamura, Y.; Torizuka, K.; Yokoyama, A.

1986-01-01

Antitumor monoclonal antibody was successfully labeled with Tc-99m by using dithiosemicarbazone (DTS) as a bifunctional chelating agent. In the first step, DTS was coupled to antibody without loss of immunoreactivity; the compound then efficiently formed a neutral 1:1 chelate with pentavalent or tetravalent Tc-99m. Imaging with Tc-99m-labeled monoclonal antibody to human osteosarcoma (OST-7) clearly displayed a small tumor in nude mice at 6 and 24 hours after intravenous administration. The tumor-to-blood ratio of the Tc-99m-labeled monoclonal antibody was higher than that of a radioiodinated antibody and similar to that of an In-111-labeled antibody. Thus, conjugation of DTS to monoclonal antibody followed by radiometalation is a simple and efficient method of preparing Tc-99m-labeled monoclonal antibody

Fragmentation, labeling and biodistribution studies of KS1/4, a monoclonal antibody

International Nuclear Information System (INIS)

Mohd, S.B.

1987-01-01

In this study, an IgG2a (KS1/4), a monoclonal antibody (MoAb) specific against a human lung adenocarcinoma (UCLA P-3) was successfully fragmented enzymatically to yield F(ab') 2 and Fab by using pepsin and papain, respectively. The kinetic of fragmentation of the MoAb was compared to that of human immunoglobulin G (IgG). A similar pattern of fragmentation was observed with both antibodies with a higher percentage yield of the F(ab') 2 and Fab obtained upon the fragmentation of the IgG by the enzymes. The KS1/4 and the two fragments were labeled with three different radionuclides, namely iodine-131, indium-111 and selenium-75. The radioiodination of the MoAb and the fragments was carried out by using a modified chloramine-T method. Radiometal labeling of the MoAb and the fragments with indium-111 was performed by using DTPA as a bifunctional chelating agent, while intrinsic labeling of the MoAb was done by culturing the hybridoma in the presence of 75 Se-methionine. The biodistribution of the radiolabeled MoAb, F(ab') 2 and Fab fragments were performed by injecting the preparations intravenously into nude mice bearing human lung adenocarcinoma

Labeling of antibodies with a /sup 67/Ga-phenolic aminocarboxylic acid chelate. Pt. 1. Chemistry and labeling technique

Energy Technology Data Exchange (ETDEWEB)

Schuhmacher, J.; Matys, R.; Hauser, H.; Maier-Borst, W.; Matzku, S.

1986-11-01

As a chelating agent for labeling antibodies (Abs) with metallic radionuclides, a propionic acid substituted ethylenediamine N, N'-di-((o-hydroxyphenyl) acetic acid) (P-EDDHA), which tighly complexes /sup 67/Ga, was synthetized. The /sup 67/Ga-P-EDDHA chelate was coupled in aqueous solution to IgG at a molar ratio of 1:1 via carbodiimide. The average coupling yield was 15%. A specific activity of 4 mCi/mg IgG could be obtained with commercially supplied /sup 67/Ga. In vitro stability was evaluated in human serum at 37/sup 0/C and showed a half-life of about 120 h for the release of /sup 67/Ga from the labeled Ab during the initial phase of incubation. This in vitro halflife is similar to that measured for /sup 111/In-DTPA labeled Abs. Because of the high stability of the /sup 67/Ga-P-EDDHA chelate, the in vivo formation of radioactive lebeled transferrin by transchelation, as described for /sup 111/In-DTPA labeled Abs, should, however, be reduced by this labeling technique.

Experimental radioimmunotherapy of a xenografted human glioma using [sup 131]I-labeled monoclonal antibody to epidermal growth factor receptor

Energy Technology Data Exchange (ETDEWEB)

Takahashi, Hiroshi; Nakazawa, Shozo [Nippon Medical School, Tokyo (Japan); Herlyn, D

1993-09-01

[sup 131]I-labeled F (ab')[sub 2] fragments of murine monoclonal antibodies (MAb) 425 specific to the epidermal growth factor receptor expressed on human gliomas were used in experimental human malignant glioma immunotherapy. Two injections of 150 [mu]Ci [sup 131]I-labeled 425 F(ab')[sub 2] achieved growth inhibition of U-87MG human malignant glioma xenografts in nude mice. This radiolabeled specific MAb F(ab')[sub 2] was significantly superior to radiolabeled fragments of an anti-hepatitis virus control MAb A5C3 in influencing tumor growth. However, similar treatment of established human malignant glioma xenografts did not inhibit progressive tumor growth significantly. No clear tumor inhibition was produced by unlabeled MAb 425F(ab')[sub 2]. These studies suggest that [sup 131]I-labeled MAbs have a significant antitumor effect where unmodified antibody is ineffective. Multiple doses of antibody may achieve an increase in labeled MAb concentration in tumors. (author).

PET imaging of osteosarcoma in dogs using a fluorine-18-labeled monoclonal antibody fab fragment

Energy Technology Data Exchange (ETDEWEB)

Page, R.L.; Garg, P.K.; Gard, S. [North Carolina State Univ., Raleigh, NC (United States)]|[Duke Univ. Medical Center, Durham, NC (United States)]|[North Carolina and Norke Radium Hospital, Oslo (Norway)] [and others

1994-09-01

Four dogs with histologically confirmed osteogenic sarcoma were studied with PET following intravenous injection of the {sup 18}F-labeled Fab fragment of TP-3, a monoclonal antibody specific for human and canine osteosarcomas. The antibody fragment was labeled using the N-succinimidyl (8-(4{prime}-({sup 18}F)fluorobenzyl)amino)suberate acylation agent. Blood clearance of activity was biphasic in all dogs but half-times were variable (T{sub 1/2{beta}} = 2-13 hr). Catabolism of labeled Fab was reflected by the decrease in protein-associated activity in serum from more than 90% at 1 min to 60%-80% at 4 hr. PET images demonstrated increased accumulation of {sup 18}F at the primary tumor site relative to normal contralateral bone in one dog as early as 15 min after injection. Biopsies obtained after euthanasia indicated higher uptake at the edges of the tumor as observed on the PET scans. Tumor uptake was 1-3 x 10{sup -3}% injected dose/g, a level similar to that reported for other Fab fragments in human tumors. In the three dogs with metastatic disease, early PET images reflected activity in the blood pool but later uptake was observed in suspected metastatic sites. These results, although preliminary, suggest that PET imaging of {sup 18}F-labeled antibody fragments is feasible and that dogs with spontaneous tumors could be a valuable model for preclinical research with radioimmunoconjugates. 34 refs., 6 figs., 2 tabs.

PET imaging of osteosarcoma in dogs using a fluorine-18-labeled monoclonal antibody fab fragment

International Nuclear Information System (INIS)

Page, R.L.; Garg, P.K.; Gard, S.

1994-01-01

Four dogs with histologically confirmed osteogenic sarcoma were studied with PET following intravenous injection of the 18 F-labeled Fab fragment of TP-3, a monoclonal antibody specific for human and canine osteosarcomas. The antibody fragment was labeled using the N-succinimidyl (8-(4'-( 18 F)fluorobenzyl)amino)suberate acylation agent. Blood clearance of activity was biphasic in all dogs but half-times were variable (T 1/2β = 2-13 hr). Catabolism of labeled Fab was reflected by the decrease in protein-associated activity in serum from more than 90% at 1 min to 60%-80% at 4 hr. PET images demonstrated increased accumulation of 18 F at the primary tumor site relative to normal contralateral bone in one dog as early as 15 min after injection. Biopsies obtained after euthanasia indicated higher uptake at the edges of the tumor as observed on the PET scans. Tumor uptake was 1-3 x 10 -3 % injected dose/g, a level similar to that reported for other Fab fragments in human tumors. In the three dogs with metastatic disease, early PET images reflected activity in the blood pool but later uptake was observed in suspected metastatic sites. These results, although preliminary, suggest that PET imaging of 18 F-labeled antibody fragments is feasible and that dogs with spontaneous tumors could be a valuable model for preclinical research with radioimmunoconjugates. 34 refs., 6 figs., 2 tabs

Radioimmunoimaging of human colon carcinoma grafted into nudemice using 131I-labeled monoclonal anticea antibody and its F(ab')2 fragments

International Nuclear Information System (INIS)

Liu Guangda

1988-01-01

131 I-labeled monoclonal anti-CEA antibody and its F(ab') 2 fragments were injected into nude mice bearing human colon carcinoma xenografts for tumor localization and radioimmunoimaging studies. Transplanted tumors were visualized in 12 hours after injection of the labeled anti-CEA or its F(ab') 2 by gamma camera. Biodistribution data indicated that F(ab') 2 fragments were cleared more rapidly from blood (T 1/2 = 13.3 h for F(ab') 2 , T 1/2 = 21.1 h for intact antibody) over 6-24 h and had higher tumor blood ratios. The intact antibody was concentrated in the tumor better than F(ab') 2 . In double-label experiments, a nonspecific localization of the control ( 125 I-labeled anti-HCG) in the tumor was also observed

Labelling, quality control and clinical evaluation of monoclonal antibodies for scintigraphy. Final report of a co-ordinated research programme 1991-1996

International Nuclear Information System (INIS)

1998-03-01

Realizing the potential of labelled monoclonal antibodies for in vivo diagnosis and therapy and the interest in many developing Member States for acquiring expertise in this field the IAEA initiated a co-ordinated research programme in 1991 focusing on 99 Tc m labelling of antibodies, their quality control and scintigraphic evaluation. Twelve laboratories from Asia, Latin America, Europe and North America participated in this programme which was concluded in 1996. During this programme the participants investigated the 99 Tc m labelling of a murine anti-CEA antibody using the method of chelating 99 Tc m with the free sulfhydryl groups generated by reaction with reducing agents such as mercapto ethanol. During the later part of the programme this method was also extended to 99 Tc m labelling of hIgG. All the participating laboratories could gain valuable experience in 99 Tc m antibody labelling techniques and formulation of kits. Many of them have been use in patients by collaborating nuclear medicine specialists with satisfactory results. This report is a compilation of the detailed results obtained by the participating laboratories and includes a summary and assessment of the achievement of the CRP

Sequences of 12 monoclonal anti-dinitrophenyl spin-label antibodies for NMR studies

International Nuclear Information System (INIS)

Leahy, D.J.; Rule, G.S.; Whittaker, M.M.; McConnell, H.M.

1988-01-01

Eleven monoclonal antibodies specific for a spin-labeled dinitrophenyl hapten (DNP-SL) have been produces for use in NMR studies. They have been named AN01 and ANO3-AN12. The stability constants for the association of these antibodies with DNP-SL and related haptens were measured by fluorescence quenching. cDNA clones coding for the heavy and light chains of each antibody and of an additional anti-DNP-SL monoclonal antibody, ANO2, have been isolated. The nucleic acid sequence of the 5' end of each clone has been determined, and the amino acid sequence of the variable regions of each antibody has been deduced from the cDNA sequence. The sequences are relatively heterogeneous, but both the heavy and the light chains of ANO1 and ANO3 are derived from the same variable-region gene families as those of the ANO2 antibody. ANO7 has a heavy chain that is related to that of ANO2, and ANO9 has a related light chain. ANO5 and ANO6 are unrelated to ANO2 but share virtually identical heavy and light chains. Preliminary NMR difference spectra comparing related antibodies show that sequence-specific assignment of resonances is possible. Such spectra also provide a measure of structural relatedness

Radiopharmaceutical labeling research

International Nuclear Information System (INIS)

Anon.

1985-01-01

The objective of this research is to develop methods of attaching radionuclides to monoclonal antibodies and antibody fragments for use in tumor imaging and internal radiation therapy. Monoclonal antibodies and their fragments are of interest because they enable the selective targeting of tumors. The labeled antibodies could be employed as carriers to transport radioisotopes to tumors, thus minimizing total-body radiation dose and radiation damage to normal tissue. Because the time required for labeled antibodies to find the tumor antigen and deliver the dose to the tumor is estimated to be about 1-3 days, radionuclides with a l- to 3-day half-life would be optimum for this purpose. Two of the radionuclides produced at LAMPF, 67 Cu and 77 Br, have the suitable half-life and nuclear-decay properties for use in tumor imaging or therapy with radiolabeled antibodies. These radionuclides and the efforts to prepare radiolabeled antibodies with them are described. We have used three different approaches to meet this objective of labeling antibodies: (1) labeling chelating agents with metal radionuclides, then conjugating the labeled chelating agents to antibodies; (2) conjugating activated chelating agents to antibodies, followed by metalation with metal radionuclides; and (3) radiobrominating small molecules that can be conjugated to antibodies

Application and evolution of several therapy nuclides labelled antibody in tumour therapy

International Nuclear Information System (INIS)

He Jiaheng; Luo Shunzhong; Wang Guanquan

2004-12-01

Radiolabeled Monoclonal antibody had a lot of merits, such as decreasing the lesion because of the external exposure to normal tissue and the whole body, destroying cancer cells which McAb could not reach, and little ornamentation effect by Antigen. Therefor, it gradually became a kind of guiding therapy method which endowed with practical value. Up to now, the radionuclides which be used for tumour radioimmunotherapy included mostly 131 I, 90 Y, 188 Re, 186 Re, 153 Sm, 211 At, et al. The application and evolution of several therapy nuclides labelled antibody in tumour therapy are in troduced. (authors)

Dual isotope study of iodine-125 and indium-111-labeled antibody in athymic mice

Energy Technology Data Exchange (ETDEWEB)

Carney, P.L.; Rogers, P.E.; Johnson, D.K. (Abbott Laboratories, Abbott Park, IL (USA))

1989-03-01

Monoclonal antibody B72.3 was coupled to a benzylisothiocyanate derivative of diethylenetriaminepentaacetic acid (DTPA). The maximum substitution achievable without loss of immunoreactivity was three DTPA groups per immunoglobulin molecule. The resulting conjugate was labeled with {sup 111}In by brief incubation with {sup 111}InCl{sub 3}, giving a mean radiochemical yield of {sup 111}In-labeled antibody of 96%. The ({sup 111}In)B72.3 preparation was mixed with an ({sup 125}I) B72.3 preparation, obtained by the chloramine-T method, and the mixture administered to athymic mice bearing subcutaneous LS174T colon carcinoma xenografts. There were no significant differences (p greater than 0.1) in the biodistributions of the two labels at 1, 2, 5, and 7 days postinjection. These results are contrasted with prior studies showing elevated levels of {sup 111}In in liver, spleen, and kidneys using B72.3-DTPA conjugates prepared via the bicyclic anhydride. It is concluded that protein cross-linking and/or the formation of unstable chelate sites in anhydride coupled conjugates underlie these disparities.

Dual isotope study of iodine-125 and indium-111-labeled antibody in athymic mice

International Nuclear Information System (INIS)

Carney, P.L.; Rogers, P.E.; Johnson, D.K.

1989-01-01

Monoclonal antibody B72.3 was coupled to a benzylisothiocyanate derivative of diethylenetriaminepentaacetic acid (DTPA). The maximum substitution achievable without loss of immunoreactivity was three DTPA groups per immunoglobulin molecule. The resulting conjugate was labeled with 111 In by brief incubation with 111 InCl 3 , giving a mean radiochemical yield of 111 In-labeled antibody of 96%. The [ 111 In]B72.3 preparation was mixed with an [ 125 I] B72.3 preparation, obtained by the chloramine-T method, and the mixture administered to athymic mice bearing subcutaneous LS174T colon carcinoma xenografts. There were no significant differences (p greater than 0.1) in the biodistributions of the two labels at 1, 2, 5, and 7 days postinjection. These results are contrasted with prior studies showing elevated levels of 111 In in liver, spleen, and kidneys using B72.3-DTPA conjugates prepared via the bicyclic anhydride. It is concluded that protein cross-linking and/or the formation of unstable chelate sites in anhydride coupled conjugates underlie these disparities

Radiotoxicity of systemically administered 211At-labeled human/mouse chimeric monoclonal antibody: a long-term survival study with histologic analysis

International Nuclear Information System (INIS)

McLendon, Roger E.; Archer, Gary E.; Larsen, Roy H.; Akabani, Gamal; Bigner, Darell D.; Zalutsky, Michael R.

1999-01-01

Purpose: The antitenascin human/mouse chimeric monoclonal antibody labeled with the α-particle-emitting radionuclide 211 At is of interest as an endo radiotherapeutic agent for the treatment of brain tumors. To facilitate the investigation of 211 At-labeled chimeric 81C6 in patients, the long-term radiotoxicity of this radiopharmaceutical has been evaluated. Methods and Materials: Antibody labeling was performed using N-succinimidyl 3-[ 211 At]astato-benzoate. After an initial dose-finding experiment, a second toxicity study was carried out at 4 dose levels in groups of 30 non thyroid blocked B6C3F 1 mice per group (15 males, 15 females). Male mice received either saline or 15-81 kBq/g and females received either saline or 16-83 kBq/g of 211 At-labeled antibody. Ten animals (5 males, 5 females) were followed for 6 months and the remainder for 1 year. Results: The lethal dose in 10% of animals (LD 10 ) for 211 At-labeled chimeric 81C6 was 46 kBq/g in females and 102 kBq/g in males. Toxic effects--perivascular fibrosis of the intraventricular septum of the heart, bone marrow suppression, splenic white pulp atrophy, and spermatic maturational delay--generally were confined to a few animals receiving the highest doses of labeled antibody. Conclusions: The LD 10 of 211 At-labeled chimeric 81C6 in this mouse strain was about half that of [ 211 At]astatide. These results establish the preclinical maximum tolerated dose of 211 At-labeled chimeric 81C6 and define in the mouse the target organs for toxicity. These studies will be useful for determining starting doses for clinical studies with 211 At-labeled chimeric 81C6

Labeling of monoclonal antibodies with a /sup 67/Ga phenolic aminocarboxylic acid chelate. Pt. 2. Comparison of immunoreactivity and biodistribution of monoclonal antibodies labeled with the /sup 67/Ga chelate or with /sup 131/I

Energy Technology Data Exchange (ETDEWEB)

Matzku, S.; Schuhmacher, J.; Kirchgessner, H.; Brueggen, J.

1986-11-01

Coupling of the /sup 67/Ga-P-EDDHA chelate via carbodiimide to the anti-melanoma monoclonal antibody (MAb) M.2.9.4 resulted in a low degree of oligomerization, but a considerable degree of intra-molecular (inter-chain) cross-linking. However, this did not impair immunoreactivity, nor did the half-life in vivo differ substantially from that of /sup 131/I-M.2.9.4. Biodistribution analysis in normal mice showed Ga:I ratios near 1 in the blood and other tissues not involved in degradation and label excretion. In tissues of the reticulo-endothelial system (RES) and the kidneys, Ga:I ratios up to 2.51 were reached within 4 days of administration. In antigen-positive MeWo tumor tissue, retention of /sup 67/Ga also exceeded that of /sup 131/I, so that tumor : organ ratios (except tumor : liver) were superior for the /sup 67/Ga-labeled MAb. It is concluded that the method of coupling pre-established /sup 67/Ga-P-EDDHA chelate to antibody, results in a functionally intact tracer molecule, whose persistence in vivo is not significantly impaired. The major difference to I-labeled MAbs may be prolonged retention of Ga in tissues (cells) physiologically involved in antibody catabolism.

sup 99m Tc-labelled anti NCA-95 antibodies in prosthetic heart valve endocarditis

Energy Technology Data Exchange (ETDEWEB)

Bair, H J; Becker, W; Wolf, F [Dept. of Nuclear Medicine, Univ. Erlangen-Nuernberg, Erlangen (Germany); Volkholz, H J [Dept. of Internal Medicine 1, Univ. of Erlangen-Nuernberg, Erlangen (Germany)

1991-08-01

A 54-y old women with earlier replacement of the mitral and aortic valves and clinical signs of localized endocarditis was studied with {sup 99m}Tc-labelled anti NCA-95 antibody. Whereas echocardiographic findings were negative, increased radionuclide uptake was observed left parasternal over the mitral valve as a sign of prosthetic valve endocarditis. This result could be confirmed by a similar study with leukocytes labelled in vitro with {sup 111}In-oxine. (orig.).

Lymphoma imaging with a new technetium-99m labelled antibody, LL2

International Nuclear Information System (INIS)

Murthy, S.; Sharkey, R.M.; Goldenberg, D.M.; Lee, R.E.; Pinsky, C.M.; Hansen, H.J.; Burger, K.; Swayne, L.C.

1992-01-01

The lesion detection capability of a new technetium-99m labelled B-cell lymphoma monoclonal antibody (MoAb) imaging agent, LL2, was evaluated in 8 patients with non-Hodgkin's lymphoma and 1 patient with chronic lymphocytic leukaemia. The MoAb kit consists of a 1-vial, 1-mg Fab' form of LL2 ready for instant labelling with technetium. The patients were injected with ∝925 MBq (25 mCi) of 99m Tc-LL2 Fab' (1 mg), and planar and single photon emission tomography (SPET) studies were performed at 3-4 h post injection and at 24 h. There was no evidence of thyroid or stomach activity up to 24 h. Uniform splenic uptake was seen in all patients. Two non-lymphoma patients were also administered with the same agent and demonstrated a similar splenic distribution; therefore, splenic targeting was not scored as tumour-specific. A total of 29 from 48 tumour sites were detected by scintigraphy, including tumours of various grades and histological types. Excluding 1 patient who had a large tumour burden of over 500 g, 29 of 33 lesions were detected. One patient was free of disease at the time of the study and had a negative scan. Another patient showed excellent targeting of gallium-negative sites in the liver and bone. The bone involvement was not known prior to the antibody study and was subsequently confirmed by a bone scan. Additional sites of MoAb localization could not be followed in this group, since most patients went on to radioimmunotherapy immediately following the 99m Tc-LL2 study. However, these initial results suggest that this new 99m Tc-labelled antibody imaging kit should be further investigated for its potential role in the staging and follow-up of lymphoma patients. (orig.)

Colorectal carcinoma metastases: Detection with In-111-labeled monoclonal antibody CCR 086

International Nuclear Information System (INIS)

Abdel-Nabi, H.H.; Levine, G.; Lamki, L.M.; Murray, J.L.; Tauxe, W.N.; Shah, A.N.; Patt, Y.Z.; Doerr, R.J.; Klein, H.A.; Gona, J.

1990-01-01

A phase I/II clinical trial with indium-111-labeled antimucin murine monoclonal antibody (MoAb) CCR 086 was conducted. Seventeen patients with histologically proved colorectal carcinoma and known metastatic disease underwent external scintigraphy after administration of 5.5 mCi (203.5 MBq) of In-111 CCR 086 at doses of 5 and 20 mg. Of 25 known lesions, 17 were detected (sensitivity, 68%). The smallest detected lesion in the lung was 1 cm and in the liver was 1.5 cm. The serum half-life of In-111-labeled CCR 086 MoAb was approximately 64 hours. The formation of human antimouse antibody (HAMA) was detected in the serum of four of five patients who received 20 mg of MoAb. No HAMAs were detected in four patients receiving 5 mg of MoAb. No side effects were encountered. Because of effective detection of liver and lung metastases with lower doses (5-20 mg) of CCR 086 conjugated with In-111, further investigations are warranted to assess clinical and therapeutic potentials of CCR 086 in the management of colorectal cancer

LSD1 demethylase and the methyl-binding protein PHF20L1 prevent SET7 methyltransferase-dependent proteolysis of the stem-cell protein SOX2.

Science.gov (United States)

Zhang, Chunxiao; Hoang, Nam; Leng, Feng; Saxena, Lovely; Lee, Logan; Alejo, Salvador; Qi, Dandan; Khal, Anthony; Sun, Hong; Lu, Fei; Zhang, Hui

2018-03-09

The pluripotency-controlling stem-cell protein SRY-box 2 (SOX2) plays a pivotal role in maintaining the self-renewal and pluripotency of embryonic stem cells and also of teratocarcinoma or embryonic carcinoma cells. SOX2 is monomethylated at lysine 119 (Lys-119) in mouse embryonic stem cells by the SET7 methyltransferase, and this methylation triggers ubiquitin-dependent SOX2 proteolysis. However, the molecular regulators and mechanisms controlling SET7-induced SOX2 proteolysis are unknown. Here, we report that in human ovarian teratocarcinoma PA-1 cells, methylation-dependent SOX2 proteolysis is dynamically regulated by the LSD1 lysine demethylase and a methyl-binding protein, PHD finger protein 20-like 1 (PHF20L1). We found that LSD1 not only removes the methyl group from monomethylated Lys-117 (equivalent to Lys-119 in mouse SOX2), but it also demethylates monomethylated Lys-42 in SOX2, a reaction that SET7 also regulated and that also triggered SOX2 proteolysis. Our studies further revealed that PHF20L1 binds both monomethylated Lys-42 and Lys-117 in SOX2 and thereby prevents SOX2 proteolysis. Down-regulation of either LSD1 or PHF20L1 promoted SOX2 proteolysis, which was prevented by SET7 inactivation in both PA-1 and mouse embryonic stem cells. Our studies also disclosed that LSD1 and PHF20L1 normally regulate the growth of pluripotent mouse embryonic stem cells and PA-1 cells by preventing methylation-dependent SOX2 proteolysis. In conclusion, our findings reveal an important mechanism by which the stability of the pluripotency-controlling stem-cell protein SOX2 is dynamically regulated by the activities of SET7, LSD1, and PHF20L1 in pluripotent stem cells. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

Part-per-trillion level detection of estradiol by competitive fluorescence immunoassay using DNA/dye conjugate as antibody multiple labels.

Science.gov (United States)

Zhu, Shengchao; Zhang, Qin; Guo, Liang-Hong

2008-08-22

Fluorescent organic dyes are currently the standard signal-generating labels used in microarray quantification. However, new labeling strategies are needed to meet the demand for high sensitivity in the detection of low-abundance proteins and small molecules. In this report, a long-chain DNA/dye conjugate was used to attach multiple fluorescence labels on antibodies to improve signal intensity and immunoassay sensitivity. Compared with the 30 base-pair (bp) oligonucleotide used in our previous work [Q. Zhang, L.-H. Guo, Bioconjugate Chem. 18 (2007) 1668-1672], conjugation of a 219 bp DNA in solution with a fluorescent DNA binder SYBR Green I resulted in more than sixfold increase in signal intensity, consistent with the increase in bp number. In a direct immunoassay for the detection of goat anti-mouse IgG in a mouse IgG-coated 96-well plate, the long DNA conjugate label also produced higher fluorescence than the short one, accompanied by about 15-fold improvement in the detection limit. To demonstrate its advantage in real applications, the DNA/dye conjugate was employed in the competitive immunoassay of 17beta-estradiol, a clinically and environmentally important analyte. The biotin-terminated DNA was attached to biotinylated anti-estradiol antibody through the biotin/streptavidin/biotin bridge after the immuno-reaction was completed, followed by conjugation with SYBR Green I. The limit of detection for 17beta-estradiol is 1.9 pg mL(-1), which is 200-fold lower than the assay using fluorescein-labeled antibodies. The new multiple labeling strategy uses readily available reagents, and is also compatible with current biochip platform. It has great potential in the sensitive detection of protein and antibody microarrays.

Development of radioactivity labelling method of new antibody by using the antibody engineering

International Nuclear Information System (INIS)

Yamazaki, Takeshi; Nakajima, Osamu; Saito, Yoshiro; Hachisuka, Akiko; Tanaka, Toichi; Sawada, Junichi

1999-01-01

With an aim to develop a method to produce labelled antibodies with low immunogenicity, two recombinant fusion proteins; scFv-His and scFv-MTβ were produced using gene engineering techniques. The former was constructed with scFv-antibody and histidine hexamer, a metal-chelated protein (or peptide). The latter was done with scFv-antibody and β-domain of metallothionein. Then, antigen-binding activity and metal-binding activity of these fusion proteins were determined using gel-filtration chromatography and ELISA. The main antigen-binding activity of scFv-His preparation was detected in a domain of about 25-30 kDa, which agreed with the peak of 29 kDa corresponding to the presumed molecular weight for the protein. Whereas the antigen-binding activity of scFv-MTβ was found in a domain of 30-35 kDa, which agreed with 32 kDa, the presumed molecular weight of scFv-MTβ. Gel-filtration chromatography of scFv-His preparation after the addition of Cu 2+ ion revealed an optical absorption at 280 nm and a Cu-peak near at 14 kDa. These results suggested that the metal affinity of the histidine-hexamer was too weak to chelate Cu 2+ in a solution. The chromatography of scFv-MTβ preparation added with Cd 2+ showed a peak of Cd appeared around a position of about 20 kDa but the peak was not coincident with that of the antigen-binding activity (ca. 30 kDa), suggesting that the present preparation of scFv-MTβ had no Cd-binding activity due to metal-exchange reaction. Based on these results, problems on the production of recombinant scFv-antibody fused with metal-binding domain of cystein-binding type or histidine-binding one were discussed. (M.N.)

Labelling, quality control and clinical evaluation of monoclonal antibodies for scintigraphy. Final report of a co-ordinated research programme 1991-1996

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-03-01

Realizing the potential of labelled monoclonal antibodies for in vivo diagnosis and therapy and the interest in many developing Member States for acquiring expertise in this field the IAEA initiated a co-ordinated research programme in 1991 focusing on {sup 99}Tc{sup m} labelling of antibodies, their quality control and scintigraphic evaluation. Twelve laboratories from Asia, Latin America, Europe and North America participated in this programme which was concluded in 1996. During this programme the participants investigated the {sup 99}Tc{sup m} labelling of a murine anti-CEA antibody using the method of chelating {sup 99}Tc{sup m} with the free sulfhydryl groups generated by reaction with reducing agents such as mercapto ethanol. During the later part of the programme this method was also extended to {sup 99}Tc{sup m} labelling of hIgG. All the participating laboratories could gain valuable experience in {sup 99}Tc{sup m} antibody labelling techniques and formulation of kits. Many of them have been use in patients by collaborating nuclear medicine specialists with satisfactory results. This report is a compilation of the detailed results obtained by the participating laboratories and includes a summary and assessment of the achievement of the CRP. Refs, figs, tabs.

The study of conjugation of anti-CD20 monoclonal antibody for labeling with metallic or lanthanides radionuclides

International Nuclear Information System (INIS)

Akanji, Akinkunmi Ganiyu

2012-01-01

Lymphomas are malignancies or cancers that start from the malign transformation of a lymphocyte in the lymphatic system. Generally, lymphomas start from the lymph nodes or from the agglomeration of the lymphatic tissues, organs like stomach, intestines, in some cases it can involve the bone marrow and the blood, it can also disseminate to other organs. Lymphomas are divided in two major categories: Hodgkin lymphoma and non-Hodgkin lymphoma (NHL). Patient with NHL are generally treated with radiotherapy alone or combined with immunotherapy using monoclonal antibody rituximab (MabThera®). Currently, monoclonal antibodies (Acm) conjugated with bifunctional chelate agents and radiolabeled with metallic or lanthanides radionuclides are a treatment reality for patients with NHL by the principle of radioimmunotherapy (RIT). This study focused on the conditions of conjugation of Acm rituximab (MabThera®) with bifunctional chelating agents DOTA and DTPA. Various parameters were studied: method of Acm purification, conditions of Acm conjugation, the method for determination of number of chelate agent coupled to the Acm, method for purification of the conjugated antibody Acm, conditions of labeling of the conjugated antibody with lutetium-177, method of purification of the radiolabeled immuno conjugate, method of radiochemical purity (RP), specific binding in vitro Raji cells (Human Burkitt) and biological distribution performed in normal Balb-c mouse. The three methodologies employed in pre-purification of Acm (dialysis, size exclusion chromatograph and dial filtration) demonstrated to be efficient; they provided sample recovery exceeding 90%. However, the methodology of dial filtration presents minimal sample loss, and gave the final recovery of the sample in micro liters; thereby facilitating sample use in subsequent experiments. Numbers of chelators attached to the Acm molecule was proportional to the molar ratio studied. When we evaluated the influence of different

Fluorescently labeled chimeric anti-CEA antibody improves detection and resection of human colon cancer in a patient-derived orthotopic xenograft (PDOX) nude mouse model.

Science.gov (United States)

Metildi, Cristina A; Kaushal, Sharmeela; Luiken, George A; Talamini, Mark A; Hoffman, Robert M; Bouvet, Michael

2014-04-01

The aim of this study was to evaluate a new fluorescently labeled chimeric anti-CEA antibody for improved detection and resection of colon cancer. Frozen tumor and normal human tissue samples were stained with chimeric and mouse antibody-fluorophore conjugates for comparison. Mice with patient-derived orthotopic xenografts (PDOX) of colon cancer underwent fluorescence-guided surgery (FGS) or bright-light surgery (BLS) 24 hr after tail vein injection of fluorophore-conjugated chimeric anti-CEA antibody. Resection completeness was assessed using postoperative images. Mice were followed for 6 months for recurrence. The fluorophore conjugation efficiency (dye/mole ratio) improved from 3-4 to >5.5 with the chimeric CEA antibody compared to mouse anti-CEA antibody. CEA-expressing tumors labeled with chimeric CEA antibody provided a brighter fluorescence signal on frozen human tumor tissues (P = 0.046) and demonstrated consistently lower fluorescence signals in normal human tissues compared to mouse antibody. Chimeric CEA antibody accurately labeled PDOX colon cancer in nude mice, enabling improved detection of tumor margins for more effective FGS. The R0 resection rate increased from 86% to 96% with FGS compared to BLS. Improved conjugating efficiency and labeling with chimeric fluorophore-conjugated antibody resulted in better detection and resection of human colon cancer in an orthotopic mouse model. © 2013 Wiley Periodicals, Inc.

99mTc-HMPAO labeled leucocyte, 99mTc-labeled antigranulocyte antibody and 67Ga scintigraphy in the evaluation of painful hip and knee prosthetic replacements

International Nuclear Information System (INIS)

Oliveira, S.; Pereira, L.; Joao, F.; Lima, J.

2003-01-01

Full text: Objective: To evaluate the utility of 99mTc-HMPAO labeled leucocyte, 99mTc-labeled anti-granulocyte antibody and 67Ga scintigraphy in patients suspected to have infected hip and knee replacements, from March/1998 to March/ 2002. Methods: Retrospective study of 33 patients (12 male, 21 female) with an average age of 61,1 ± 7,3 years. Nineteen had hip replacements and 14 were submitted to knee replacements. 99mTc-HMPAO labeled leucocyte scintigraphy was performed in 17 patients, 99mTc-labeled anti-granulocyte antibody scintigraphy in 13 patients and 67Ga scintigraphy in 3 patients. Twenty-six patients were also submitted to 3-phase 99mTc-MDP bone scintigraphy. Results were compared to those from studies with infection/inflammation agents. Concordant positive studies were considered to be a positive result for infection. A second study using 67Ga was also performed in 3 patients. Results: Diagnosis was based on surgical findings in 14 patients, pathologic study of biopsy specimen in 1 case and clinical/ imaging follow-up in 18 patients. Infection was detected in 22 cases and absent in 11. The conjoined evaluation of scintigraphic studies considered infection to be present in 20 cases and absent in 13. With infection/inflammation agents, 20 cases were positive (+) and 13 cases were negative (-). Using 99mTc-HMPAO labeled leucocytes, 12 cases were (+) and 5 cases were (-). With 99mTc-labeled anti-granulocyte antibodies, 8 cases were (+) and 5 were (-). With 67Ga, all 3 cases were (-). In patients with (+) studies using infection/ inflammation agents, a false positive case with 99mTc-HMPAO labeled leucocytes was reported. Two false negative cases were detected, both with 99mTc-labeled antigranulocyte antibodies, in patients with (-) studies. Regarding the studies with 99mTc-MDP, 24 were (+) and 2 were (-). Eighteen of these (+) cases were also (+) in studies with infection/inflammation agents, but 6 were (-) with these agents. Negative cases were also (-) in

Subcellular localization of estradiol receptor in MCF7 cells studied with nanogold-labelled antibody fragments.

Science.gov (United States)

Kessels, M M; Qualmann, B; Thole, H H; Sierralta, W D

1998-01-01

Ultrastructural localization studies of estradiol receptor in hormone-deprived and hormone-stimulated MCF7 cells were done using F(ab') fragments of three different antibodies (#402, 13H2, HT277) covalently linked to nanogold. These ultra-small, non-charged immunoreagents, combined with a size-enlargement by silver enhancement, localized estradiol receptor in both nuclear and cytoplasmic areas of non-stimulated target cells; stimulation with the steroid induced a predominantly nuclear labelling. In the cytoplasm of resting cells, tagging was often observed at or in the proximity of stress fibers. In the nucleus a large proportion of receptor was found inside the nucleolus, specially with the reagent derived from antibody 13H2. We postulate that different accessibilities of receptor epitopes account for the different labelling densities observed at cytoskeletal elements and the nucleoli.

Screening for epitope specificity directly on culture supernatants in the early phase of monoclonal antibody production by an ELISA with biotin-labeled antigen

DEFF Research Database (Denmark)

Andersen, Ditte C; Jensen, Charlotte H; Gregersen, Annemette

2004-01-01

This report describes an assay for comparison of epitope specificity in groups of monoclonal antibodies against a given antigen. The only prerequisite is the biotin-labeled antigen. One of the monoclonal antibodies is captured onto a plastic surface via a rabbit anti-mouse Ig, and the other...... preincubated with biotinylated antigen. When the two antibodies react with the same epitope subsequent binding of the biotin-labeled antigen is abolished (inhibition). In the cases where no inhibition was observed, the two antibodies were considered to react with distinct, independent epitopes. The obvious...

Cation-exchange antibody labeling for simultaneous electrochemical detection of tumor markers CA15-3 and CA19-9

International Nuclear Information System (INIS)

Wang, Guangjie; Qing, Yi; Shan, Jinlu; Jin, Feng; Wang, Dong; Yuan, Ruo

2013-01-01

We report on a new kind of non-covalent multi-label electrochemical immunoassay that was applied to simultaneously quantify the tumor markers CA15-3 and CA19-9. The method employs a nanohybrid composed of an ionomer and conductive titanium dioxide nanoparticles that act as a matrix support for the antibodies. The two antibodies (anti-CA153 and anti-CA199) were labeled (a) with a cobaltous dipyridine complex, and (b) with methylene blue. Labeling is based on cation-exchange interaction rather than on covalent conjugation. The redox potentials of the two labels are separated by an interval of 0.3 V. The resulting sandwich-type immunosensor was read out by differential pulse voltammetry. The potential sites and currents of the two redox probes reflect the concentration of the two analytes. The two analytes were determined with a detection limit of 1.6 U mL −1 for CA19-9, and of 0.3 U mL −1 for CA15-3 (author)

Preparation of {sup 125}I-labeled monoclonal antibody of bladder neoplasm using lactoperoxidase

Energy Technology Data Exchange (ETDEWEB)

Huaifen, Li; Huisheng, Niu; Mingyue, Yuan; Yongzhi, Huang [Chinese Acaolemy of Medical Sciences, Tianjin (China). Inst. of Radiation Medicine

1994-11-01

{sup 125}I-labelled monoclonal antibody of bladder neoplasm ({sup 125}I-L{sub 4}B{sub 4}) is prepared using lactoperoxidase. The in-vivo radioactive distribution of {sup 125}I-L{sub 4}B{sub 4} in bare mice shows that {sup 125}I-L{sub 4}B{sub 4} concentrates in the tumour.

Radioimmunoscintigraphy of human pancreatic carcinoma xenografts in nude mice with 131I-labeled monoclonal antibody

International Nuclear Information System (INIS)

Tsuda, Takatoshi; Koshiba, H.; Usui, T.; Kubota, M.; Kikuchi, Kokichi; Morita, Kazuo

1990-01-01

Encouraged by reports of radioimmunoimaging of colorectal carcinomas and by examining an immunohistochemical report on resected pancreas cancer tissues, we studied the diagnostic potential of radioimmunoimaging with the radioiodinelabeled monoclonal antibody (MoAb; HC-1) to a human pancreas cancer cell line (HGC25) was labeled with radioiodine and injected into athymic nude mice implanted with human pancreas cancer cells. Antibody HC-1 was cleared from the circulation and accumulated significantly in the implanted tumor sites. (author)

Labeling of antibodies with a 67Ga-phenolic aminocarboxylic acid chelate. Pt. 1

International Nuclear Information System (INIS)

Schuhmacher, J.; Matys, R.; Hauser, H.; Maier-Borst, W.; Matzku, S.

1986-01-01

As a chelating agent for labeling antibodies (Abs) with metallic radionuclides, a propionic acid substituted ethylenediamine N, N'-di-[(o-hydroxyphenyl) acetic acid] (P-EDDHA), which tighly complexes 67 Ga, was synthetized. The 67 Ga-P-EDDHA chelate was coupled in aqueous solution to IgG at a molar ratio of 1:1 via carbodiimide. The average coupling yield was 15%. A specific activity of 4 mCi/mg IgG could be obtained with commercially supplied 67 Ga. In vitro stability was evaluated in human serum at 37 0 C and showed a half-life of about 120 h for the release of 67 Ga from the labeled Ab during the initial phase of incubation. This in vitro halflife is similar to that measured for 111 In-DTPA labeled Abs. Because of the high stability of the 67 Ga-P-EDDHA chelate, the in vivo formation of radioactive lebeled transferrin by transchelation, as described for 111 In-DTPA labeled Abs, should, however, be reduced by this labeling technique. (orig.)

Radionuclide and Fluorescence Imaging of Clear Cell Renal Cell Carcinoma Using Dual Labeled Anti-Carbonic Anhydrase IX Antibody G250.

Science.gov (United States)

Muselaers, Constantijn H J; Rijpkema, Mark; Bos, Desirée L; Langenhuijsen, Johan F; Oyen, Wim J G; Mulders, Peter F A; Oosterwijk, Egbert; Boerman, Otto C

2015-08-01

Tumor targeted optical imaging using antibodies labeled with near infrared fluorophores is a sensitive imaging modality that might be used during surgery to assure complete removal of malignant tissue. We evaluated the feasibility of dual modality imaging and image guided surgery with the dual labeled anti-carbonic anhydrase IX antibody preparation (111)In-DTPA-G250-IRDye800CW in mice with intraperitoneal clear cell renal cell carcinoma. BALB/c nu/nu mice with intraperitoneal SK-RC-52 lesions received 10 μg DTPA-G250-IRDye800CW labeled with 15 MBq (111)In or 10 μg of the dual labeled irrelevant control antibody NUH-82 (20 mice each). To evaluate when tumors could be detected, 4 mice per group were imaged weekly during 5 weeks with single photon emission computerized tomography/computerized tomography and the fluorescence imaging followed by ex vivo biodistribution studies. As early as 1 week after tumor cell inoculation single photon emission computerized tomography and fluorescence images showed clear delineation of intraperitoneal clear cell renal cell carcinoma with good concordance between single photon emission computerized tomography/computerized tomography and fluorescence images. The high and specific accumulation of the dual labeled antibody conjugate in tumors was confirmed in the biodistribution studies. Maximum tumor uptake was observed 1 week after inoculation (mean ± SD 58.5% ± 18.7% vs 5.6% ± 2.3% injected dose per gm for DTPA-G250-IRDye800CW vs NUH-82, respectively). High tumor uptake was also observed at other time points. This study demonstrates the feasibility of dual modality imaging with dual labeled antibody (111)In-DTPA-G250-IRDye800CW in a clear cell renal cell carcinoma model. Results indicate that preoperative and intraoperative detection of carbonic anhydrase IX expressing tumors, positive resection margins and metastasis might be feasible with this approach. Copyright © 2015 American Urological Association Education and Research

Imaging endocarditis with Tc-99m-labeled antibody--an experimental study: concise communication

Energy Technology Data Exchange (ETDEWEB)

Wong, D.W.; Dhawan, V.K.; Tanaka, T.; Mishkin, F.S.; Reese, I.C.; Thadepalli, H.

1982-03-01

The sensitivity and specificity of Tc-99m-labeled antibacterial antibody (Tc-99m Ab) for detecting bacterial endocarditis were evaluated in an experimental model. Rabbit-produced antistaphylococcal antibody was extracted using Rivanol and chemically labeled with Tc-99m. This Tc-99m Ab was injected intravenously in New Zealand rabbits 24 hr after producing Staphylococcus aureus endocarditis of the aortic valve. Imaging and tissue analyses were performed on the following day. All 11 animals developed S. aureus aortic-valve vegetations and showed increased uptake of Tc-99m Ab at the aortic valve, 118 times higher than at the uninfected tricuspid valve. Although high hepatic radioactivity and anatomic uncertainties interfered with in vivo delineation of these lesions, images of the excised hearts showed all affected valves. Two rabbits inoculated with Escherichia coli did not develop endocarditis and had little uptake of Tc-99m Ab, while six rabbits with enterococcal endocarditis had no uptake of the Tc-99m Ab in their vegetations. The findings suggest potential value of Tc-99m Ab on the rapid diagnosis of endocarditis.

Imaging endocarditis with Tc-99m-labeled antibody--an experimental study: concise communication

International Nuclear Information System (INIS)

Wong, D.W.; Dhawan, V.K.; Tanaka, T.; Mishkin, F.S.; Reese, I.C.; Thadepalli, H.

1982-01-01

The sensitivity and specificity of Tc-99m-labeled antibacterial antibody (Tc-99m Ab) for detecting bacterial endocarditis were evaluated in an experimental model. Rabbit-produced antistaphylococcal antibody was extracted using Rivanol and chemically labeled with Tc-99m. This Tc-99m Ab was injected intravenously in New Zealand rabbits 24 hr after producing Staphylococcus aureus endocarditis of the aortic valve. Imaging and tissue analyses were performed on the following day. All 11 animals developed S. aureus aortic-valve vegetations and showed increased uptake of Tc-99m Ab at the aortic valve, 118 times higher than at the uninfected tricuspid valve. Although high hepatic radioactivity and anatomic uncertainties interfered with in vivo delineation of these lesions, images of the excised hearts showed all affected valves. Two rabbits inoculated with Escherichia coli did not develop endocarditis and had little uptake of Tc-99m Ab, while six rabbits with enterococcal endocarditis had no uptake of the Tc-99m Ab in their vegetations. The findings suggest potential value of Tc-99m Ab on the rapid diagnosis of endocarditis

Targeting of indium 111-labeled bivalent hapten to human melanoma mediated by bispecific monoclonal antibody conjugates: Imaging of tumors hosted in nude mice

International Nuclear Information System (INIS)

Le Doussal, J.M.; Gruaz-Guyon, A.; Martin, M.; Gautherot, E.; Delaage, M.; Barbet, J.

1990-01-01

Antibody conjugates were prepared by coupling F(ab')2 or Fab' fragments of an antibody specific for the human high molecular weight-melanoma associated antigen to Fab' fragments of an antibody specific for indium-diethylenetriaminepentaacetate complexes. Monovalent and bivalent haptens were synthesized by reacting the dipeptide tyrosyl-lysine with diethylenetriaminepentaacetic cyclic anhydride. In vitro, the antibody conjugate mediated binding of the 111In-labeled haptens to melanoma cells. In vivo, it allowed specific localization of the haptens in A375 tumors. The bivalent hapten exhibited much higher efficiency at targeting 111In onto cells, both in vitro and in vivo. Antibody conjugate and hapten doses (2 micrograms and 1 pmol, respectively) and the delay between antibody conjugate and tracer injections (24 h) were adjusted to maximize tumor uptake (4% injected dose/g) and tumor to normal tissue contrast (greater than 3) obtained 3 h after injection of the 111In-labeled bivalent hapten. This two-step technique, when compared to direct targeting of 111In-labeled F(ab')2 fragments, provided lower localization of injected activity into the tumor (x 0.25), but higher tumor/tissue ratios, especially with respect to liver (x 7), spleen (x 8), and kidneys (x 10). In addition, high contrast images were obtained within 3 hours, instead of days. Thus, antibody conjugate-mediated targeting of small bivalent haptens, labeled with short half-life isotopes, is proposed as a general method for improving tumor radioimmunolocalization

Detection of deep venous thrombosis with indium 111-labelled monoclonal antibody against tissue plasminogen activator

Energy Technology Data Exchange (ETDEWEB)

Tromholt, N.; Hesse, B. (Hilleroed County Hospital (Denmark). Dept. of Clinical Physiology); Folkenborg, O. (Isotope-Pharmcy, Broenshoej (Denmark)); Selmer, J. (Novo Industri A/S, Bagsvaerd (Denmark)); Nielsen, N.T. (Hilleroed County Hospital (Denmark). Dept. of Radiology)

1991-05-01

The administration of a radiolabelled monoclonal antibody against tissue plasminogen activator allows detection of areas with increased fibrinolytic activity, i.e. those with an active thrombotic lesion. Eight patients with phlebographically verified deep venous thrombosis were examined. At the time of immunoscintigraphy study they were examined receiving anticoagulant therapy. Some 75-85 MBq {sup 111}In-labelled antibody were injected, and scintigrams were obtained after 30 min and after 24 h. The precise site of the thrombus could not be visualized after 30 min due to high background activity, whereas after 24 h it was detectable in all patients. The thrombus/background ratios achieved are twice as high as those observed in a human antifibrin antibody study. These preliminary data suggest a high sensitivity of our PA-specific antibody for the detection of active deep venous thrombosis in man, and our antibody seems to offer theoretical advantages over both platelet and fibrin-specific antibodies. (orig.).

Detection of deep venous thrombosis with indium 111-labelled monoclonal antibody against tissue plasminogen activator

International Nuclear Information System (INIS)

Tromholt, N.; Hesse, B.; Selmer, J.; Nielsen, N.T.

1991-01-01

The administration of a radiolabelled monoclonal antibody against tissue plasminogen activator allows detection of areas with increased fibrinolytic activity, i.e. those with an active thrombotic lesion. Eight patients with phlebographically verified deep venous thrombosis were examined. At the time of immunoscintigraphy study they were examined receiving anticoagulant therapy. Some 75-85 MBq 111 In-labelled antibody were injected, and scintigrams were obtained after 30 min and after 24 h. The precise site of the thrombus could not be visualized after 30 min due to high background activity, whereas after 24 h it was detectable in all patients. The thrombus/background ratios achieved are twice as high as those observed in a human antifibrin antibody study. These preliminary data suggest a high sensitivity of our PA-specific antibody for the detection of active deep venous thrombosis in man, and our antibody seems to offer theoretical advantages over both platelet and fibrin-specific antibodies. (orig.)

Optimization of the personnel radiation protection during the treatment by antibodies labelled by yttrium 90

International Nuclear Information System (INIS)

Legrand, J.; Prangere, T.; Cougnenc, O.; Leleu, C.; Huglo, D.; Morschhauser, F.

2007-01-01

Beyond the acquired experience limiting the exposure time, measures of adequate radiation protection allow to reduce the doses of surface received to extremities by the personnel participating to the preparation of treatments by antibodies labelled by yttrium 90. (N.C.)

In vitro stability of EDTA and DTPA immunoconjugates of monoclonal antibody 2G3 labeled with indium-111

Energy Technology Data Exchange (ETDEWEB)

Reilly, R.; Lee, N.; Houle, S. (The Toronto Hospital (Canada)); Law, J.; Marks, A. (Toronto Univ., ON (Canada))

1992-08-01

Monoclonal antibody 2G3 directed against a high molecular weight glycoprotein on breast and ovarian cancer cells was conjugated with bicyclic DTPA (or EDTA) anhydride or benzyl isothiocyanate DTPA (benzyl DTPA) and labeled with {sup 111}In. DTPA anhydride was more reactive with the antibody than benzyl DTPA, and kinetics of labeling with {sup 111}In were more rapid for DTPA substituted 2G3 than for benzyl DTPA substituted 2G3. On the other hand, {sup 111}In-2G3 conjugates prepared using DTPA anhydride were subject to more extensive dimerization and higher losses in immunoreactivity than those prepared using benzyl DTPA. On the basis of measurement of transchelation to transferrin, the stability of {sup 111}In-2G3 prepared using DTPA anhydride or benzyl DTPA did not differ during incubation in human plasma for 6 days at 37{sup o}C. These results suggest that an important advantage of benzyl DTPA over DTPA anhydride for preparing {sup 111}In-labeled antibodies is the prevention of intermolecular (and intramolecular) crosslinking during conjugation which ultimately leads to alterations in conformation and losses in immunoreactivity of the radioimmunoconjugate. (author).

Monoclonal antibodies and coupling reagents to cell membrane proteins for leukocyte labeling

International Nuclear Information System (INIS)

McAfee, J.G.; Gagne, G.; Subramanian, G.; Schneider, R.F.

1984-01-01

Current gamma-emitting agents for tagging leukocytes, In-111 oxine or tropolone, label all cell types indiscriminantly, and nuclear localization in lymphocytes results in radiation damage. Coupling reagents and murine monoclonal antibodies (Mab) specific for cell surface antigens of human leukocytes were tried as cell labeling agents to avoid nuclear localization. 10/sup 8/ mixed human leukocytes in Hepes buffer were added to tubes coated with 5 mg of dry cyclic dianhydride of DTPA for 15 minutes at room temperature. After washing, 0.1 ml of In-111 Cl in ACD (pH 6.8) was added. After 30 minutes, a cell labeling yield of 23% was obtained. Washing the cells in an elutriation centrifuge showed that this label was irreversible. Mab for cell surface antigens of human granulocytes were labeled with 300 μCi of I-125 using the Iodobead technic and unbound activity was removed by gel column chromatography. 1-10 μg were added to 10/sup 8/ mixed leukocytes in 0.5 ml plasma or saline for 1 hr. With Mab anti-leu M4 (clone G7 E11), an IgM, the cell labeling yield was 21%, irreversible, and specific for granulocytes. With anti-human leukocyte Mab NEI-042 (clone 9.4), and IgG2a, and anti-granulocyte Mab MAS-065 (clone FMCl1) an IgG1, the cell labeling was relatively unstable. Labeling of leukocyte subpopulations with Mab is feasible, and the binding of multivalent IgM is stronger than that of other immunoglobulins. DTPA cyclic anhydride is firmly bound to cell membranes, but the labeling is non-specific

Comparison of therapeutic efficacy and biodistribution of 213Bi- and 211At-labeled monoclonal antibody MX35 in an ovarian cancer model

DEFF Research Database (Denmark)

Gustafsson, Anna M E; Bäck, Tom; Elgqvist, Jörgen

2012-01-01

The purpose of this study was to compare the therapeutic efficacy and biodistribution of the monoclonal antibody MX35 labeled with either (213)Bi or (211)At, both α-emitters, in an ovarian cancer model.......The purpose of this study was to compare the therapeutic efficacy and biodistribution of the monoclonal antibody MX35 labeled with either (213)Bi or (211)At, both α-emitters, in an ovarian cancer model....

Effects of radiolysis on yttrium-90-labeled Lym-1 antibody preparations.

Science.gov (United States)

Salako, Q A; O'Donnell, R T; DeNardo, S J

1998-04-01

The physical half-life of 2.6 days and 2.2 MeV beta emissions of 90Y provide excellent properties for radioimmunotherapy applications. However, the clinically useful beta particles may be a source of radiation-induced damage of 90Y-labeled immunoconjugate radiopharmaceuticals during preparation or short-term storage. The stability of 90Y-labeled Lym-1 antibody was studied in standard radiopharmacy conditions to establish a formulation at which radiolysis is not a problem. Lym-1-21T-BAD immunoconjugate intermediate was prepared according to our standard procedure, then labeled with 90Y at 1, 2, 4 and 9.4 mCi/mg Lym-1 using 0.5 M tetramethylammonium acetate, pH 7, labeling buffer. Each mixture was challenged in diethylenetriaminepentaacetic acid to remove nonspecifically bound 90Y. The 90Y-21T-BAD-Lym-1 products were purified by centrifuged molecular sieving column chromatography. The radiochemical purity and immunoreactivity of each preparation was monitored daily by high-performance liquid chromatography (HPLC) and solid-phase radioimmunoassay, respectively, for 3 days. The preparation at 2 mCi/mg was also formulated in 4% (wt/vol) human serum albumin (HSA) overall and at 9.4 mCi/mg in five-fold water, 4 and 10% (wt/vol) HSA overall; all were monitored as above. The monomeric quality and purity profile of products at 1 and 2 mCi/mg were retained (> or = 80%) as was their immunoreactivity (> or = 75%) over 3 days. The radiochemical purity and immunoreactivity of the product at 4 mCi/mg declined to 65% and 28%, respectively, by 3 days after preparation and in just 48 hr, the product at 9.4 mCi/mg had degraded to 21% in radiochemical purity with only 3% immunoreactivity. The current HPLC data and earlier published chromatographic evidence did not support a compromised radiochemical integrity of 90Y-DOTA complexes by loss of 90Y from the DOTA chelate. Radiolysis of 90Y-labeled antibody preparations did not appear to be a problem at 90Y-21T-BAD-Lym-1 products < or = 2 m

Antibody guided targeting of non-small cell lung cancer using 111In-labeled HMFG1 F(ab')2 fragments

International Nuclear Information System (INIS)

Kalofonos, H.P.; Sivolapenko, G.B.; Courtenay-Luck, N.S.

1988-01-01

Immunoscintigraphy using F(ab')2 fragments of tumor-associated monoclonal antibody HMFG1 was performed in 14 patients with primary and metastatic non-small cell carcinoma of lung cancer. The antibody was conjugated with diethylenetriamine pentaacetic acid and labeled with 111 In. Quality control studies showed efficient incorporation of 111 In onto antibody (5 mCi/mg), no significant loss of immunoreactivity, and in vitro and in vivo stability. The optimal time for imaging was between 48 and 72 h. Following i.v. administration, serum activity fell rapidly (t1/2a = 2.5 +/- 1.3 (SD) h; t1/2b = 42 +/- 4.5 h). The majority of the radioactivity was associated with the plasma and not with the blood cells. All patients had a significant concentration of 111 In in the liver (approximately 20% of the injected dose, 48 h postadministration). No toxicity was encountered. No human antimurine-IgG antibody was detected in any of the patients within 4 months of follow-up, even in patients receiving two administrations of F(ab')2 fragments. Localization of all primary lesions and the majority (80%) of metastatic lesions was achieved. Seven of 14 patients were also studied using a 111 In-labeled nonspecific antibody (Fab')2 fragment (4C4). In three patients the specificity index was higher than the other four (P less than 0.05). We conclude that although successful targeting of 111 In-labeled (Fab')2 fragments of HMFG1 can be achieved in patients with non-small cell carcinoma of lung, observable tumor localization can also be achieved using a nonspecific antibody

Tracking of boron-labelled monoclonal antibodies by energy loss spectroscopy in the electron microscope: a preliminary report

International Nuclear Information System (INIS)

Moore, D.E.; Dawes, A.L.; Chandler, A.K.; Bradstock, K.F.

1990-01-01

A technique is being developed, based on electron energy loss spectroscopy in the transmission electron microscope, whereby the binding of monoclonal antibodies to their specific receptors and any subsequent movement or endocytosis can be studied in cell culture. The method requires that antibodies be labelled with a low atomic number element, such as boron. Two procedures have been established enabling up to 1200 boron atoms to be attached per antibody molecule without affecting the immunoreactivity. In the first method, dodecaborane cages are attached to polyornithine bridging molecules which in turn are covalently bound to the antibody using a photosensitive reagent. The second technique makes use of the extremely high biotin-avidin affinity by attaching biotin to the antibody and dodecaborane cages to avidin before mixing the two components. 13 refs., 2 figs

{sup 99m}Tc-labeled chimeric anti-NCA 95 antigranulocyte monoclonal antibody for bone marrow imaging

Energy Technology Data Exchange (ETDEWEB)

Sarwar, M.; Higuchi, Tetsuya; Tomiyoshi, Katsumi [Gunma Univ., Maebashi (Japan). School of Medicine] [and others

1998-09-01

Chimeric mouse-human antigranulocyte monoclonal antibody (ch MAb) against non-specific cross-reacting antigen (NCA-95) was labeled with {sup 99m}Tc (using a direct method) and {sup 125}I (using the chloramine T method), and its binding to human granulocytes and LS-180 colorectal carcinoma cells expressing carcinoembryonic antigen on their surfaces, cross-reactive with anti-NCA-95 chimeric monoclonal antibody, increased in proportion to the number of cells added and reached more than 80% and 90%, respectively. In biodistribution studies, {sup 99m}Tc and {sup 125}I-labeled ch anti-NCA-95 MAb revealed high tumor uptake, and the tumor-to-blood ratio was 2.9 after 24 hours. The tumor-to-normal-organ ratio was also more than 3.0 in all organs except for the tumor-to-kidney ratio. Scintigrams of athymic nude mice confirmed the results of biodistribution studies that showed higher radioactivity in tumor and kidney of the mice administered with {sup 99m}Tc-labeled ch MAb. A normal volunteer injected with {sup 99m}Tc-labeled ch anti-NCA-95 antigranulocyte MAb showed clear bone marrow images, and a patient with aplastic anemia revealed irregular uptake in his lumbar spine, suggesting its utility for bone marrow scintigraphy and for the detection of hematological disorders, infections, and bone metastasis. (author)

Use of Re-188 labelled anti-EGFr humanized monoclonal antibody h-R3 for radioimmunotherapy of gliomas

International Nuclear Information System (INIS)

Perera, A.; Torres, L.A.; Lopez, G.; Casaco, A.; Batista, J.F.; Pena, Y.; Coca, M.A.; Leyva, R.; Garcia, I.

2007-01-01

Full text: Locally administered monoclonal antibodies labelled with radioisotopes like 90Y, 131I, 186Re, 212Bi, 211At, 177Lu and others, constitute a viable and promising alternative for management different kind of malignancies. The development of 188W/188Re generator has given the possibility of having a radionuclide showing satisfactory features for radioimmunotherapy (Eb2.12 MeV, Eg155 keV, T1/2=16.9 h and easy to make labelling approaches, similar to used for 99mTc). Neuroepithelial-derived tumours show an increased expression of the EGF receptor with regard to adjacent normal tissue. This overexpression could be related with the autocrine stimulation of the neoplasm by EGF and TGFb. Humanized monoclonal antibody h-R3 has shown a high affinity for this EGF receptor, blocking the binding of EGF to it receptor and inducing apoptosis. Thus, it could be a good candidate for radioimmunotherapy of neuroepithelial malignancies. The aim of the present work was to label monoclonal antibody h-R3 with 188Re, to assess it in an animal model and evaluate its internal dosimetry and toxicity in patients with grade III-IV gliomas through a phase I clinical trial. Schwarz's direct labelling method was employed. Briefly, a 2000-fold molar excess of 2-mercaptoethanol was used to reduce bisulfide bonds of the antibody. The amount of sodium glucoheptonate, ascorbic acid and stannous fluoride were varied to achieve optimum labelling yield. 188Re-labeling yield was proportional to the volume of stannous glucoheptonate solution added to the formulation. Radiochemical purity of 188Re-h-R3 was 98.0±0.4%. Challenge against 300-fold molar excess of L-cysteine was made to assess the stability of the tracer. There was no significant difference between stability of 188Re-h-R3 and 99mTc-h-R3 against cysteine challenge up to 24 h. Animal biodistribution study was performed at 3 and 24 h after intravenous administration of 188Re-h-R3 through tale vein of Male Wistar rats. The results were

Screening for epitope specificity directly on culture supernatants in the early phase of monoclonal antibody production by an ELISA with biotin-labeled antigen.

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Andersen, Ditte C; Jensen, Charlotte H; Gregersen, Annemette; Brandt, Jette; Kliem, Anette; Skjødt, Karsten; Koch, Claus; Teisner, Børge

2004-01-01

This report describes an assay for comparison of epitope specificity in groups of monoclonal antibodies against a given antigen. The only prerequisite is the biotin-labeled antigen. One of the monoclonal antibodies is captured onto a plastic surface via a rabbit anti-mouse Ig, and the other preincubated with biotinylated antigen. When the two antibodies react with the same epitope subsequent binding of the biotin-labeled antigen is abolished (inhibition). In the cases where no inhibition was observed, the two antibodies were considered to react with distinct, independent epitopes. The obvious advantages using this assay, are that it can be performed directly on culture supernatants in the early phase of monoclonal antibody production, and also works for antigens with repetitive epitopes. Moreover, the bonus effect, i.e., a signal in excess of the reference signal when sets of monoclonal antibodies with different epitope specificity are compared, gives a relative measure of affinity.

Mouse-specific antibody responses to a monoclonal antibody during repeated immunoscintigraphy investigations: Comparison of antibody titres and imaging studies in a rat model

International Nuclear Information System (INIS)

Pimm, M.V.; Gribben, S.J.; Markham, A.J.; Perkins, A.C.

1990-01-01

As a model for human mouse-specific antibody responses in patients undergoing immunoscintigraphy, we have investigated in rats the production of mouse-specific antibodies (MA) to the mouse monoclonal antibody 791T/36. At intervals of between 5 and 16 weeks the rats were given repeated cycles of intravenous (IV) injections of antibody with or without a simultaneous intradermal (ID) injection. The IV dose was 60 μg/kg, a dose similar to that used in many clinical immunoscintigraphy studies. The ID injection was 2 μg, which mimicks the skin test dose often given in clinical imaging protocols. The study was carried out with both 131 I-labelled antibody and with antibody labelled with 111 In by DTPA chelation. MA was measured with a passive haemagglutination assay using sheep red blood cells coated with the monoclonal antibody. Of rats given ID injections of unlabelled antibody at the same time as the IV imaging doses, 9/20 produced MA during 4 cycles of injections. In contrast, only 2/16 rats given only the IV dose produced MA. Both 131 I- and 111 In-labelled antibody appeared equally immunogenic with 5/18 and 6/18 overall responders, respectively. The production of MA was associated with a significant perturbation in the biodistribution of the IV dose of labelled antibody as seen by gamma-camera imaging of the rats given 111 In-labelled antibody. There was clearance of immune complexes to the liver, this organ accumulating up to 90% of the whole body count rate of radiolabel. MA titres of between 1/100 and 1/78000 caused equal perturbation of biodistribution, although below 1/100 the effect was more variable. (orig.)

The labelling of monoclonal antibody with 211At via diazo salts of aromatic diamine

International Nuclear Information System (INIS)

Jin Jiannan; Zhang Shuyuan; Zhou Maolun; Liu Ning

1992-01-01

A method was described for labelling CEA monoclonal antibody (CEA-McAb) with the α-emitting nuclide 211 At via diazo salts of p-phenylenediamine or benzidine. Aromatic diamine were transformed into diazo salts and subsequently both 211 At and CEA-McAb react with diazo salts to produce 211 At-CEA-McAb conjugates. The reaction and purification required about 2.5 h. Sephadex G-75 column was used to separate the labelled CEA-McAb from reactive products and the labelling yield was at least 30% of the initial activity of 211 At. The specific activity of 211 At-CEA-McAb (2.2-3.7) x 10 4 Bq/μg(McAb) could be achieved. The results of tissue distribution of 211 At in mice showed that 211 At-CEA-McAb conjugates were stable in vivo

Fluorescent humanized anti-CEA antibody specifically labels metastatic pancreatic cancer in a patient-derived orthotopic xenograft (PDOX) mouse model

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Lwin, Thinzar M.; Miyake, Kentaro; Murakami, Takashi; DeLong, Jonathan C.; Yazaki, Paul J.; Shivley, John E.; Clary, Bryan; Hoffman, Robert M.; Bouvet, Michael

2018-03-01

Specific tumor targeting can result in selective labeling of cancer in vivo for surgical navigation. In the present study, we show that the use of an anti-CEA antibody conjugated to the near-infrared (NIR) fluorescent dye, IRDye800CW, can selectively target and label pancreatic cancer and its metastases in a clinically relevant patient derived xenograft mouse model.

Spin-labelling study of interactions of ovalbumin with multilamellar liposomes and specific anti-ovalbumin antibodies.

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Brgles, Marija; Mirosavljević, Krunoslav; Noethig-Laslo, Vesna; Frkanec, Ruza; Tomasić, Jelka

2007-03-10

Ovalbumin (OVA) has been used continuously as the model antigen in numerous studies of immune reactions and antigen processing, very often encapsulated into liposomes. The purpose of this work was to study the possible interactions of spin-labelled OVA and lipids in liposomal membranes using electron spin resonance (ESR) spectroscopy. OVA was covalently spin-labelled with 4-maleimido-2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO-maleimide), characterized and encapsulated into multilamellar, negatively charged liposomes. ESR spectra of this liposomal preparation gave evidence for the interaction of OVA with the lipid bilayers. Such an interaction was also evidenced by the ESR spectra of liposomal preparation containing OVA, where liposomes were spin-labelled with n-doxyl stearic acids. The spin-labelled OVA retains its property to bind specific anti-OVA antibodies, as shown by ESR spectroscopy, but also in ELISA for specific anti-OVA IgG.

A solid-phase radioimmunoassay for IgG gliadin antibodies using 125I-labelled staphylococcal protein A

International Nuclear Information System (INIS)

Troncone, R.; Pignata, C.; Farris, E.; Ciccimarra, F.

1983-01-01

A sensitive radioimmunoassay for IgG gliadin antibodies is described. Serum specimens were added to wells of plastic microtitre plates coated with gliadin. After removal of the unbound material, gliadin antibodies were detected by adding 125 I-labelled staphylococcal protein A ( 125 I-SpA). Serum specimens from coeliac patients on a normal diet or on a gluten-free diet were tested, as well as sera from an age-matched control group. Measurements to obtain precise quantitative values were made with gliadin antibody-rich serum as reference standard. High titres of gliadin antibodies were found in 18 out of 19 coeliac patients on a normal diet (95%); in patients on a strict gluten-free diet serum values did not exceed 2 S.D. of the control mean. Due to the high sensitivity of the method a low but detectable amount of gliadin antibody was present in the sera of all controls. (Auth.)

Solid-phase radioimmunoassay for IgG gliadin antibodies using /sup 125/I-labelled staphylococcal protein A

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Troncone, R.; Pignata, C.; Farris, E.; Ciccimarra, F. (Naples Univ. (Italy). II Facolta di Medicina)

1983-10-14

A sensitive radioimmunoassay for IgG gliadin antibodies is described. Serum specimens were added to wells of plastic microtitre plates coated with gliadin. After removal of the unbound material, gliadin antibodies were detected by adding /sup 125/I-labelled staphylococcal protein A (/sup 125/I-SpA). Serum specimens from coeliac patients on a normal diet or on a gluten-free diet were tested, as well as sera from an age-matched control group. Measurements to obtain precise quantitative values were made with gliadin antibody-rich serum as reference standard. High titres of gliadin antibodies were found in 18 out of 19 coeliac patients on a normal diet (95%); in patients on a strict gluten-free diet serum values did not exceed 2 S.D. of the control mean. Due to the high sensitivity of the method a low but detectable amount of gliadin antibody was present in the sera of all controls.

Detection of human cancer in an animal model using radio-labelled tumour-associated monoclonal antibodies

International Nuclear Information System (INIS)

Epenetos, A.A.; Arklie, J.; Knowles, R.W.; Bodmer, W.F.

1982-01-01

Monoclonal antibodies to epithelial-cell antigenic determinants, labelled with 123 I and 125 I, were administered parenterally to immunodeficient mice bearing human tumours derived from a human cancer cell line. Anterior, posterior and lateral radioscans of the body were taken with a gamma scintillation camera at various times from immediately to 65 days after injection. Visual displays of the images were processed by standard computer techniques. The model used a human colon-cancer cell line, HT29, and the monoclonal antibody, AUAl, which is specific to an epithelial proliferating antigen. Tumour detection was achieved in all the mice. The smallest tumour detectable appeared to be about 1 mm in diameter. The degree of antibody uptake in a tumour depended on its size and the blood supply of its surrounding tissues. (author)

Label Free QCM Immunobiosensor for AFB1 Detection Using Monoclonal IgA Antibody as Recognition Element

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Özlem Ertekin

2016-08-01

Full Text Available This study introduces the use of an IgA isotype aflatoxin (AF specific monoclonal antibody for the development of a highly sensitive Quartz Crystal Microbalance (QCM immunobiosensor for the detection of AF in inhibitory immunoassay format. The higher molecular weight of IgA antibodies proved an advantage over commonly used IgG antibodies in label free immunobiosensor measurements. IgA and IgG antibodies with similar affinity for AF were used in the comparative studies. Sensor surface was prepared by covalent immobilization of AFB1, using self assembled monolayer (SAM formed on gold coated Quartz Crystal, with 1-Ethyl-3-(3-dimethylaminopropyl carbodiimide/N-hydroxy succinimide (EDC/NHS method using a diamine linker. Nonspecific binding to the surface was decreased by minimizing the duration of EDC/NHS activation. Sensor surface was chemically blocked after AF immobilization without any need for protein blocking. This protein free sensor chip endured harsh solutions with strong ionic detergent at high pH, which is required for the regeneration of the high affinity antibody-antigen interaction. According to the obtained results, the detection range with IgA antibodies was higher than IgG antibodies in QCM immunosensor developed for AFB1.

Quantitative assessment of antibody internalization with novel monoclonal antibodies against Alexa fluorophores.

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Liao-Chan, Sindy; Daine-Matsuoka, Barbara; Heald, Nathan; Wong, Tiffany; Lin, Tracey; Cai, Allen G; Lai, Michelle; D'Alessio, Joseph A; Theunissen, Jan-Willem

2015-01-01

Antibodies against cell surface antigens may be internalized through their specific interactions with these proteins and in some cases may induce or perturb antigen internalization. The anti-cancer efficacy of antibody-drug conjugates is thought to rely on their uptake by cancer cells expressing the surface antigen. Numerous techniques, including microscopy and flow cytometry, have been used to identify antibodies with desired cellular uptake rates. To enable quantitative measurements of internalization of labeled antibodies, an assay based on internalized and quenched fluorescence was developed. For this approach, we generated novel anti-Alexa Fluor monoclonal antibodies (mAbs) that effectively and specifically quench cell surface-bound Alexa Fluor 488 or Alexa Fluor 594 fluorescence. Utilizing Alexa Fluor-labeled mAbs against the EphA2 receptor tyrosine kinase, we showed that the anti-Alexa Fluor reagents could be used to monitor internalization quantitatively over time. The anti-Alexa Fluor mAbs were also validated in a proof of concept dual-label internalization assay with simultaneous exposure of cells to two different mAbs. Importantly, the unique anti-Alexa Fluor mAbs described here may also enable other single- and dual-label experiments, including label detection and signal enhancement in macromolecules, trafficking of proteins and microorganisms, and cell migration and morphology.

Quantitative assessment of antibody internalization with novel monoclonal antibodies against Alexa fluorophores.

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Sindy Liao-Chan

Full Text Available Antibodies against cell surface antigens may be internalized through their specific interactions with these proteins and in some cases may induce or perturb antigen internalization. The anti-cancer efficacy of antibody-drug conjugates is thought to rely on their uptake by cancer cells expressing the surface antigen. Numerous techniques, including microscopy and flow cytometry, have been used to identify antibodies with desired cellular uptake rates. To enable quantitative measurements of internalization of labeled antibodies, an assay based on internalized and quenched fluorescence was developed. For this approach, we generated novel anti-Alexa Fluor monoclonal antibodies (mAbs that effectively and specifically quench cell surface-bound Alexa Fluor 488 or Alexa Fluor 594 fluorescence. Utilizing Alexa Fluor-labeled mAbs against the EphA2 receptor tyrosine kinase, we showed that the anti-Alexa Fluor reagents could be used to monitor internalization quantitatively over time. The anti-Alexa Fluor mAbs were also validated in a proof of concept dual-label internalization assay with simultaneous exposure of cells to two different mAbs. Importantly, the unique anti-Alexa Fluor mAbs described here may also enable other single- and dual-label experiments, including label detection and signal enhancement in macromolecules, trafficking of proteins and microorganisms, and cell migration and morphology.

Radioimmunological imaging of metastatic prostatic cancer with 111indium-labeled monoclonal antibody PAY 276

International Nuclear Information System (INIS)

Babaian, R.J.; Murray, J.L.; Lamki, L.M.

1987-01-01

A total of 25 patients with histologically proved adenocarcinoma of the prostate, whose disease was staged clinically as D2 by appropriate radiographic and nuclear medicine studies, received increasing doses of PAY 276, an antiprostatic acid phosphatase monoclonal antibody for radioimmunological imaging. The patients were divided into 5 groups of 5. Groups 1 through 5 received an infusion of 5, 10, 20, 40 or 80 mg. monoclonal antibody, respectively, 1 mg. of which was labeled to 5 mCi. of 111 indium, while stable monoclonal antibody was added to achieve the desired antibody concentration. No patient had an allergic reaction, and no significant change in serial hemoglobin levels, platelet count, chemistry profile or results of urinalyses was noted. The monoclonal antibody scan visualized at least 1 lesion in 19 of 25 patients (76 per cent): 4 in groups 1 and 2, and all 15 in groups 3 to 5. With results of conventional radiography and bone scintigraphy considered definitive for metastases, monoclonal antibody scans detected 7 of 32 metastases (21.8 per cent) in group 3 (20 mg.), 31 of 58 (53.4 per cent) in group 4 (40 mg.) and 101 of 134 (75.4 per cent) in group 5 (80 mg). In group 5 the incidence of false positive and false negative scans was 2.3 per cent (3 of 132) and 24.6 per cent (33 of 134), respectively. The detection of metastatic lesions increased as the concentration of unlabeled monoclonal antibody increased. Radioimmunological imaging of prostatic cancer with antiprostatic acid phosphatase monoclonal antibody seems to be feasible

Detection of experimental infections with 99mTc-labeled monoclonal antibodies against TNF-α and interleukin-8

International Nuclear Information System (INIS)

Welling, Mick; Feitsma, Hans I.J.; Calame, Wim; Pauwels, Ernest K.J.

1997-01-01

This study was designed to assess monoclonal antibodies (MAbs) directed against tumor necrosis factor-α (TNF-α) (anti-TNF) or interleukin-8 (anti-IL-8) as radioactive agents for the detection of Staphylococcus aureus- or Klebsiella pneumoniae-infected thighs in mice. At 5 min (acute infection) or 20 h (established) post-infection, 20 μg of the 99m Tc-labeled MAbs were injected. At various time intervals, the accumulation of the radiotracer in the infected thighs was assessed and expressed as a target-to-nontarget (T/NT) ratio. The binding of 99m Tc-labeled MAbs to circulating mononuclear cells and granulocytes was quantitated 20 h after injection. The pharmacokinetics of the MAbs, in relation to the control agents 99m Tc-labeled polyclonal human immunoglobulin (IgG) and a 99m Tc-labeled nonspecific IgG1 MAb, were also studied. In acute infections, 99m Tc-anti-TNF accumulated to a higher extent (p 99m Tc-IgG and was higher at 0.25 h in K. pneumoniae-infected mice (p 99m Tc-IgG. In established S. aureus and K. pneumoniae infections, 99m Tc-anti-IL-8 detected the infection more intensely than 99m Tc-IgG until 1 h after injection. In both S. aureus and K. pneumoniae infections, localization of sites of infection correlates (p 99m Tc-labeled MAbs to granulocytes and mononuclear cells in both acute and established infections. It was concluded that 99m Tc-labeled MAbs, directed against TNF-α and IL-8, accumulate in bacterial infections in mice to a higher extent than does 99m Tc-IgG after infection and is related to the binding of the antibodies to blood leukocytes. With these 99m Tc-labeled MAbs, information might be gained about the development of an infection

Comparative studies of antibody anti-CD20 labeled with 188Re

International Nuclear Information System (INIS)

Dias, Carla Roberta de Barros Rodrigues

2010-01-01

Nuclear Medicine is an unique and important modality in oncology and the development of new tumor-targeted radiopharmaceuticals for both diagnosis and therapy is an area of interest for researchers. Rituximab (RTX) is a quimeric monoclonal antibody (mAb) (IgG 1) that specifically binds to CD20 antigen with high affinity and has been successfully used for the treatment of Non-Hodgkin Lymphoma (NHL) of cell B. The CD20 antigen is expressed over more than 90% of cell B NHL. Technetium-99m ( 99m Tc) and rhenium-188 ( 188 Re) are an attractive radionuclide pair for clinical use due to their favorable decay properties for diagnosis ( 99m Tc: T 1/2 = 6 h, γ radiation = 140 keV) and therapy ( 188 Re: T 1/2 = 17 h, maximum β energy = 2.12 MeV) and to their availability in the form of 99 Mo/ 99 mTc and 188 W/ 188 Re generators. The radionuclides can be conjugated to mAb using similar chemical procedures. The aim of this work was to study the labeling of anti-CD20 mAb (RTX) with 188 Re using two techniques: the direct labeling method [ 188 Re(V)] and the labeling method via the carbonyl nucleus [ 188 Re(I)]. Besides the quality control, the radiolabeled mAb was submitted to in vivo, in vitro and ex vivo biological studies. For the direct labeling, RTX was reducing by incubation with 2-mercaptoethanol for generating sulphydryl groups (-SH) and further labeled with 188 Re(V), in a study of several parameters in order to reach an optimized formulation. The labeling via the carbonyl nucleus both 99 mTc and 188 Re were employed through 2 different procedures: (1) labeling of intact RTX with 99 mTc(I) and (2) reduced RTX (RTX red ) labeled with 99 mTc(I)/ 188 Re(I). Also a parameter study was performed to obtain an optimized formulation. The quality control method for evaluating the radiochemical purity showed a good labeling yield (93%) for the direct method. The labeling method via carbonyl group, the results showed that the - SH groups of RTX red are a possible way of labeling

Use of gold nanoparticle-labeled secondary antibodies to improve the sensitivity of an immunochromatographic assay for aflatoxin B1

International Nuclear Information System (INIS)

Urusov, Alexander E.; Zherdev, Anatoly V.; Dzantiev, Boris B.

2014-01-01

We describe a sensitive method for the immunochromatographic determination of aflatoxin B1. It is based on the following steps: 1) Competitive interaction between non-labeled specific primary antibodies and target antigens in a sample and in the test zone of a membrane; 2) detection of the immune complexes on the membrane by using a secondary antibodies labeled with gold nanoparticles. The method enables precise adjustment of the required quantities of specific antibodies and the colloidal (gold) marker. It was applied in a lateral flow format to the detection of aflatoxin B1 and exhibits a limit of detection (LOD) of 160 pg · mL −1 if detected visually, and of 30 pg · mL −1 via instrumental detection. This is significantly lower than the LOD of 2 ng · mL −1 achieved by conventional lateral flow analysis using the same reagents. (author)

Preoperative clinical radioimmunodetection of pancreatic cancer by 111In-labeled chimeric monoclonal antibody Nd2

International Nuclear Information System (INIS)

Sawada, Tetsuji; Nishihara, Tamahiro; Yamamoto, Atsushi

1999-01-01

The present study was carried out with the purpose of evaluating the clinical usefulness of radioimmunodetection (RAID) with 111 In-labeled murine/human chimeric monoclonal antibody, Nd2 (c-Nd2) in patients with pancreatic cancer. Nineteen patients suspected to have pancreatic cancer were administered intravenously 74 MBq/2 mg 111 In-labeled c-Nd2 in 100 ml of saline containing 2% albumin over 30 min. A scintigram was obtained on the 3rd day after infusion by using single photon emission computed tomography (SPECT) imaging. Of the 14 patients finally diagnosed as having pancreatic cancer on the basis of surgical specimens or progress of disease, specific focal uptake at the site of the tumor was detected in 12 (true positive cases), representing a sensitivity of 85.7% (12/14), and liver metastasis was found in one case with metastasis. Of the 5 patients diagnosed with tumor-forming pancreatitis (TFP), 4 patients demonstrated true negative imaging, but one patient whose tumor demonstrated interesting findings in histology and immunostaining, showed false positive imaging. Of patients investigated for human anti-chimeric antibody (HACA) response, none showed HACA response, and no allergic reaction was seen in any of the patients administered c-Nd2. These results suggest that RAID with 111 In-labeled c-Nd2 is useful for differential preoperative diagnosis between invasive pancreatic cancer and TFP. (author)

Direct labelling of monoclonal antibodies with 99Tcm. Assessment of labelling, stability, immunoreactivity and biodistribution

International Nuclear Information System (INIS)

Janoki, G.A.

1998-01-01

Reduction of disulfide bonds to sulfhydryl groups for direct radiolabelling of monoclonal antibodies for immunoscintigraphic application continues to be of significant interest. Reducing agents that have been used are the following: stannous ion, 2-mercaptoethanol, dithiothreitol, dithioerythriol, and ascorbic acid. The radiolabelling of the reduced and purified antibody is performed via Sn 2+ reduction of pertechnetate in the presence of an excess of a low-affinity chelating ligand. In a recent work the 2-mercaptoethanol (2-ME) reduction based method was studied by using different analytical and biological techniques. Human IgG (Sandoglobulin), anti-CEA MoAb (ior-1), and anti-granulocyte MoAb (MAK 47), were reduced with 2-ME at two different molar ratios. To determine the amount of contaminating mercaptoethanol which may have survived the gel-filtration step 14 C-ME was used. The number of the free endogenous sulfhydryl groups generated by reduction was determined by Ellman's reagent; absorbance was measured at 412 nm. Within the quality assurance procedure of the 3 freeze dried kits the labelling efficiency, stability, pH, sterility, apyrogenicity, vial yield, syringe retention, filterable activity, free SH determination and animal distribution were studied again. After receiving permission from local ethics committee pilot human studies were initiated. Study protocols were also approved

Radioimmunoscintigraphy of experimental arterial and venous thrombi in animals with 99Tcm labelled monoclonal antibody against thrombus elements

International Nuclear Information System (INIS)

Ji Shundong; Liu Xiaojian; Zhang Rongjun; Wan Weixing; Jin Jian; Yuan Changgeng

2000-01-01

Object: To evaluate the use of 99 Tc m labelled anti P-Selection monoclonal antibody (McAb)SZ-51 and anti-fibrin McAb SZ-63 in detection of experimental thrombi in rabbits and dogs. Method: The McAb SZ-51 and SZ-63 were labelled by using the method of 2-imino-thiolane modification and 99 Tc m -glucoheptonate (GH) trans-chelation. The experimental femoral arterial and venous thrombosis were prepared, then 99 Tc m -McAb was injected into ear-edge vein, finally imaged by SPECT. 99 Tc m -labelled murine IgG was used as a negative control. Results: The fresh arterial and venous thrombi in dogs were clearly imaged 0.5 to 2 h and 2 to 4 h after injection of 99 Tc m -SZ-51/63 and 99 Tc m -SZ-51, respectively. The old arterial and venous thrombi in rabbits were clearly imaged 2 to 4 h after injection of 99 Tc m -SZ-63. Conclusion: the monoclonal antibody SZ-51 and SZ-63 would be a potential agent for imaging diagnosis of thrombotic disease

Method of stably radiolabeling antibodies with technetium and rhenium

International Nuclear Information System (INIS)

Paik, C.H.; Reba, R.C.; Eckelman, W.C.

1987-01-01

A method is described for labeling antibodies or antibody fragments with radionuclides of technetium or rhenium to obtain stable labeling, comprising: reacting a reduced radioisotope of technetium or rhenium with an antibody or antibody fragment, or a diethylenetriaminepentaacetic acid conjugated antibody or antibody fragment, in the presence of free or carrier-bound diethylenetriaminepentaacetic acid (DTPA). The amount of DTPA is sufficient to substantially completely inhibit binding of the reduced technetium or rhenium to nonstable binding sites of the antibody or antibody fragment, or the DTPA-conjugated antibody or antibody fragment. The resultant stably labeled antibody or antibody fragment, or DTPA[conjugated antibody or antibody fragment is recovered

Technetium-99m labeled monoclonal antibodies in the detection of metastatic melanoma

International Nuclear Information System (INIS)

Serafini, A.N.; Kotler, J.; Feun, L.; Dewanjee, M.; Robinson, D.; Salk, D.; Sfakianakis, G.; Abrams, P.; Savaraj, N.; Goodwin, D.

1989-01-01

Twenty-six stage II/III malignant melanoma patients with 321 measurable metastatic lesions were imaged using Fab fragments of an IgG murine monoclonal antibody labeled specifically with 10-30 mCi Tc-99m with a bi-functional chelating method (NeoRx, Seattle, WA). There were no side effects or adverse reactions. Immunoscintigraphy demonstrated 66.6% of lesions larger than 1 cm and 92.5% of lesions larger than 3 cm. Most frequently detected metastases were in lymph nodes, subcutaneous areas, and bone. Of lesions less than 1 cm, 23.6% were detected if superficial cutaneous lesions were excluded. The smallest detectable lesion was 4 mm. Twenty-one additional clinically unsuspected sites were visualized in 12 of the 26 patients studied. Of these, 56% were confirmed as metastasis by other tests. There were apparent nonspecific localizations owing to other causes, including fracture, varicosities, skin abscess and pneumonitis. Increased experience in image analysis facilitates correct interpretation of these localizations. This study demonstrates that imaging with Tc-99m labeled antibody fragments detects melanoma lesions in organs routinely surveyed and in other areas not routinely assessed by other imaging techniques. The procedure is readily performed and safe. The principal advantage of the test is its ability to survey the entire body and all organs with a single test. Its principal limitation, in common with other diagnostic imaging procedures, is its poor sensitivity for detecting lesions less than 1 cm

Indium-111-labelled antimyosin antibody imaging in a patient with cardiac sarcoidosis

International Nuclear Information System (INIS)

Knapp, W.H.; Bentrup, A.; Ohlmeier, H.

1993-01-01

The aetiology of cardiac dysfunction caused by sarcoid granulomatous inflammation may be difficult to clarify, and the potential of imaging methods is limited. We report on a patient who present with acute biventricular decompensation. Pulmonary sarcoidosis was confirmed after hospitalization. Four weeks after the initiation of corticosteroid treatment, scintigraphy with indium-111-labelled antimyosin antibody Fab fragments (AMAB) revealed distinct activity accumulation in major parts of the left ventricular wall (heart-lung ratio: 1.6) 72 h following injection. There may by a role for AMAB scintigraphy in the early detection of cardiac sacroidosis. (orig.)

Extracorporeal adsorption therapy: A Method to improve targeted radiation delivered by radiometal-labeled monoclonal antibodies

International Nuclear Information System (INIS)

Nemecek, Eneida R.; Green, Damian J.; Fisher, Darrell R.; Pagal, John M.; Lin, Yukang; Gopal, A. K.; Durack, Lawrence D.; Rajendran, Joseph G.; Wilbur, D. S.; Nilsson, Rune; Sandberg, Bengt; Press, Oliver W.

2008-01-01

antibody labeled with indium-111 (111In), seven patients received RIT with anti-CD20 antibody labeled with indium-111 for biokinetics and dosimetry, and therapeutic doses of antibody labeled with yttrium-90 (90Y). Performing the ECAT procedure at a rate that such that one blood volume per hour were circulated for 3 hours, resulted in mean radioactivity depletion of 96% in whole blood, 49% in whole body 49%, 62% in the lungs and 40% in liver and kidneys. There was no sufficient data to determine whether there was an improvement in the relative delivery of radiation to the tumor compared to normal organs by performing ECAT, but pharmacokinetic modeling studies suggested a potential therapeutic advantage using this approach. [refs] To evaluate the potential therapeutic advantages of ECAT, we performed biodistribution studies in nonhuman primates comparing the therapeutic ratios of radiation delivered using this approach to those delivered by conventional RIT alone. In addition, we evaluated lutetium-177 (177Lu) as an alternative isotope to optimize the delivery of RIT by improving the therapeutic index (target to non-target ratio)

A PHF8 homolog in C. elegans promotes DNA repair via homologous recombination.

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Changrim Lee

Full Text Available PHF8 is a JmjC domain-containing histone demethylase, defects in which are associated with X-linked mental retardation. In this study, we examined the roles of two PHF8 homologs, JMJD-1.1 and JMJD-1.2, in the model organism C. elegans in response to DNA damage. A deletion mutation in either of the genes led to hypersensitivity to interstrand DNA crosslinks (ICLs, while only mutation of jmjd-1.1 resulted in hypersensitivity to double-strand DNA breaks (DSBs. In response to ICLs, JMJD-1.1 did not affect the focus formation of FCD-2, a homolog of FANCD2, a key protein in the Fanconi anemia pathway. However, the dynamic behavior of RPA-1 and RAD-51 was affected by the mutation: the accumulations of both proteins at ICLs appeared normal, but their subsequent disappearance was retarded, suggesting that later steps of homologous recombination were defective. Similar changes in the dynamic behavior of RPA-1 and RAD-51 were seen in response to DSBs, supporting a role of JMJD-1.1 in homologous recombination. Such a role was also supported by our finding that the hypersensitivity of jmjd-1.1 worms to ICLs was rescued by knockdown of lig-4, a homolog of Ligase 4 active in nonhomologous end-joining. The hypersensitivity of jmjd-1.1 worms to ICLs was increased by rad-54 knockdown, suggesting that JMJD-1.1 acts in parallel with RAD-54 in modulating chromatin structure. Indeed, the level of histone H3 Lys9 tri-methylation, a marker of heterochromatin, was higher in jmjd-1.1 cells than in wild-type cells. We conclude that the histone demethylase JMJD-1.1 influences homologous recombination either by relaxing heterochromatin structure or by indirectly regulating the expression of multiple genes affecting DNA repair.

Enzyme-labeled Antigen Method: Development and Application of the Novel Approach for Identifying Plasma Cells Locally Producing Disease-specific Antibodies in Inflammatory Lesions

International Nuclear Information System (INIS)

Mizutani, Yasuyoshi; Shiogama, Kazuya; Onouchi, Takanori; Sakurai, Kouhei; Inada, Ken-ichi; Tsutsumi, Yutaka

2016-01-01

In chronic inflammatory lesions of autoimmune and infectious diseases, plasma cells are frequently observed. Antigens recognized by antibodies produced by the plasma cells mostly remain unclear. A new technique identifying these corresponding antigens may give us a breakthrough for understanding the disease from a pathophysiological viewpoint, simply because the immunocytes are seen within the lesion. We have developed an enzyme-labeled antigen method for microscopic identification of the antigen recognized by specific antibodies locally produced in plasma cells in inflammatory lesions. Firstly, target biotinylated antigens were constructed by the wheat germ cell-free protein synthesis system or through chemical biotinylation. Next, proteins reactive to antibodies in tissue extracts were screened and antibody titers were evaluated by the AlphaScreen method. Finally, with the enzyme-labeled antigen method using the biotinylated antigens as probes, plasma cells producing specific antibodies were microscopically localized in fixed frozen sections. Our novel approach visualized tissue plasma cells that produced 1) autoantibodies in rheumatoid arthritis, 2) antibodies against major antigens of Porphyromonas gingivalis in periodontitis or radicular cyst, and 3) antibodies against a carbohydrate antigen, Strep A, of Streptococcus pyogenes in recurrent tonsillitis. Evaluation of local specific antibody responses expectedly contributes to clarifying previously unknown processes in inflammatory disorders

A rapid radioimmunoassay using 125I-labeled staphylococcal protein A for antibody to varicella-zoster virus

International Nuclear Information System (INIS)

Richman, D.D.; Cleveland, P.H.; Oxman, M.N.; Zaia, J.A.

1981-01-01

A sensitive radioimmunoassay for serum antibody to varicella-zoster virus is described; it uses 125I-labeled staphylococcal protein A and a specially designed immunofiltration apparatus. The assay accurately distinguishes between individuals who are susceptible and those who are immune to infection with varicella-zoster virus. In addition, it can detect passive antibody in recipients of varicella-zoster immune globulin. This radioimmunoassay also detects the heterologous antibody responses that occasionally occur in patients infected with herpes simplex virus, which also have been detected by other antibody assays. The particular advantages of this assay are the use of noninfectious reagents, the speed of execution (less than 3 hr), the requirement for only small quantities of serum (30 microliters), the objectivity of end-point determination, and the capability of screening large numbers of sera. Consequently, this radioimmunoassay is especially useful for the rapid identification of susceptible individuals, which is essential for the appropriate management of patients and hospital personnel after exposure to varicella

99mTc-Labeling of Monoclonal Antibody to Carcinoembryonic Antigen and Biodistribution

International Nuclear Information System (INIS)

Moon, Dae Hyuk; Chung, June Key; Lee, Myu ng Chul; Koh, Chang Soon; Chung, Hong Keun; Park, Jae Gahb

1992-01-01

This study was designed to evaluate a direct method of 99m Tc labeling using β-mercaptoethanol as a reducing agent, and to investigate whether 99m Tc labeled specific monoclonal antibody against carcinoembryonic antigen (CEA-92) can be used for the scintigraphic localization of human colon cancer xenograft. Purified CEA-92 IgG was fragmented into F(ab') 2 and then labeled with 99m Tc by transchelation method using glucarate as a chelator. Labeling efficiency, immunological reactivity and in vitro stability of 99m Tc CEA-92 F(ab') 2 were measured and then injected intravenously into nude mice bearing human colon cancer (SNU-C4). Scintigrams were obtained at 24 hour after injection. Then nude mice were sacrificed and the radioactivity was measured. Labeling efficiency of injected 99m Tc CEA-92 F(ab') 2 , immunoreactive fraction and in vitro stability at 24 hour of injected 99m Tc CEA-92 F(ab') 2 was 45.2%, 32.8% and 57.4%, respectively. At 24 hour after injection, %ID/g in kidney (46.77) showed high uptake, but %ID/g in tumor (1.65) was significantly higher than spleen (0.69), muscle (0.16), intestine (0.45), stomach (0.75), heart (0.48) and blood(0.45). There was no significant difference between tumor and liver (1.81). Tumor contrast as quantitated by tumor to blood ratio of 99m Tc CEA-92 F(ab') 2 was increased significantly (p 131 I-CEA-92 F(ab') 2 . The scintigram demonstrated localization of radioactivity over transplanted tumor, but significant background radioactivity was also noted over kidney and abdomen. It is concluded that CEA-92 F(ab') 2 can be labeled with 99m Tc by a direct transchelation method using β-mercaptoethanol as a reducing agent and 99m Tc labeled CEA-92 F(ab') 2 can be used for the scintigraphic localization of human colon cancer xenograft in nude mice model.

Tumor immunolocalization using 124I-iodine-labeled JAA-F11 antibody to Thomsen-Friedenreich alpha-linked antigen

International Nuclear Information System (INIS)

Chaturvedi, Richa; Heimburg, Jamie; Yan, Jun; Koury, Stephen; Sajjad, Munawwar; Abdel-Nabi, Hani H.; Rittenhouse-Olson, Kate

2008-01-01

Clinical immunolocalization has been attempted by others with an anti-Thomsen-Friedenreich antigen (TF-Ag) mAb that bound both alpha- and beta-linked TF-Ag. In this report, 124 I-labeled mAb JAA-F11 specific for alpha-linked TF-Ag showed higher tumor specificity in in vivo micro-positron emission tomography (micro-PET) of the mouse mammary adenocarcinoma line, 4T1, showing no preferential uptake by the kidney. Labeled product remained localized in the tumor for at least 20 days. Glycan array analysis showed structural specificity of the antibody

Immunoscintigraphy and radioimmunotherapy in Cuba: experiences with labeled monoclonal antibodies for cancer diagnosis and treatment (1993-2013).

Science.gov (United States)

Peña, Yamilé; Perera, Alejandro; Batista, Juan F

2014-01-01

INTRODUCTION The availability of monoclonal antibodies in Cuba has facilitated development and application of innovative techniques (immunoscintigraphy and radioimmunotherapy) for cancer diagnosis and treatment. Objective Review immunoscintigraphy and radioimmunotherapy techniques and analyze their use in Cuba, based on the published literature. In this context, we describe the experience of Havana's Clinical Research Center with labeled monoclonal antibodies for cancer diagnosis and treatment during the period 1993-2013. EVIDENCE ACQUISITION Basic concepts concerning cancer and monoclonal antibodies were reviewed, as well as relevant international and Cuban data. Forty-nine documents were reviewed, among them 2 textbooks, 34 articles by Cuban authors and 13 by international authors. All works published by the Clinical Research Center from 1993 through 2013 were included. Bibliography was obtained from the library of the Clinical Research Center and Infomed, Cuba's national health telematics network, using the following keywords: monoclonal antibodies, immunoscintigraphy and radioimmunotherapy. RESULTS Labeling the antibodies (ior t3, ior t1, ior cea 1, ior egf/r3, ior c5, h-R3, 14F7 and rituximab) with radioactive isotopes was a basic line of research in Cuba and has fostered their use as diagnostic and therapeutic tools. The studies conducted demonstrated the good sensitivity and diagnostic precision of immunoscintigraphy for detecting various types of tumors (head and neck, ovarian, colon, breast, lymphoma, brain). Obtaining different radioimmune conjugates with radioactive isotopes such as 99mTc and 188Re made it possible to administer radioimmunotherapy to patients with several types of cancer (brain, lymphoma, breast). The objective of 60% of the clinical trials was to determine pharmacokinetics, internal dosimetry and adverse effects of monoclonal antibodies, as well as tumor response; there were few adverse effects, no damage to vital organs, and a positive

19F labelled dextrans and antibodies as NMR imaging and spectroscopy agents

International Nuclear Information System (INIS)

Antich, P.P.; Kulkarni, P.V.

1993-01-01

A method is described of NMR imaging or spectroscopy, comprising the steps of administering to a living subject a 19 F labelled NMR agent, the NMR agent comprising (a) a transport polymer selected from the group consisting of dextran polymers and amino dextrans, having a molecular weight between approximately 100 d and 500 kd, and antibodies and fragments thereof, and (b) a 19F-containing sensor moiety selected from the group consisting of fluorinated alkyls, fluorinated acetates, fluoroaniline, and fluoroalkyl phosphonates, in an amount effective to provide a detectable NMR signal; and then detecting the 19 F NMR signal produced

Radiolabelled antibodies in imaging

International Nuclear Information System (INIS)

Khaw, B.A.; Haber, E.

1982-01-01

Recent technological advances make it possible to produce pure (monoclonal) antibodies in unlimited quantities without the need for continuous immunization of animals and to label these antibodies with a variety of radionuclides which can be traced by single-photon computed tomography. An outline review of the state of the art is presented, with particular reference to the imaging of myocardial infarcts and to tumour imaging studies using labelled monoclonal antibodies (sup(99m)Tc and 125 I). Lengthy bibliography. (U.K.)

Interferon-induced changes in pharmacokinetics and tumor uptake of 111In-labeled antimelanoma antibody 96.5 in melanoma patients

International Nuclear Information System (INIS)

Rosenblum, M.G.; Lamki, L.M.; Murray, J.L.; Carlo, D.J.; Gutterman, J.U.

1988-01-01

The type I interferons [both partially purified human leukocyte interferon (HuIFN-alpha) and recombinant alpha interferon] and the type II interferons have been shown to increase the expression of tumor-associated antigens in vitro. To determine whether HuIFN-alpha could increase tumor acquisition of the antimelanoma antibody 96.5 in vivo, five patients with metastatic malignant melanoma were treated with HuIFN-alpha at a dose of 3 X 10(6) units daily by im administration. Twenty-four hours after the first dose of HuIFN-alpha, 1 mg of antibody 96.5 labeled with 5 mCi of 111 In was coadministered with 19 mg of unlabeled 96.5. Five patients matched for metastatic site and lesion size who had not received HuIFN-alpha were also given a dose of 5 mCi of radiolabeled 96.5 at the same total antibody dose (20 mg). In patients treated with HuIFN-alpha, there was a statistically significant increase in the plasma half-life of the 111 In label (39.7 +/- 3.3 hr) compared to the untreated control group (29.8 +/- 3.2 hr). In addition, there was an increase in the apparent volume of distribution of the antibody in the HuIFN-alpha group (5.56 +/- 0.67 L) compared to controls (3.15 +/- 0.5 L) suggesting both an increased immediate extravascular distribution of radiolabeled antibody and a decrease in the subsequent rate of clearance of antibody from plasma. These two phenomena result in a 28% decrease in the area under the concentration curve in the HuIFN-alpha-treated group compared to controls. Computer analysis of whole-body scans from patients showed a threefold increase in radiolabeled antibody distributed to tumor relative to blood pool but no change in organ:blood ratios for liver, spleen, bone, or kidney compared to controls

Detection of experimental thrombi in rabbits with an 131I-labelled fibrin-specific monoclonal antibody

International Nuclear Information System (INIS)

Walker, K.Z.; Milner, L.J.; Boniface, G.R.

1990-01-01

The detection of thrombi in rabbits has been investigated with 131 I-labelled DD-3B6/22, a monoclonal antibody (Mab) reactive at high affinity (Kd=2.68x10 -10 M) with human D Dimer (DD). DD-3B6/22 bound well to both 'fresh' and 'aged' human clots in an in vitro assay but showed poor binding to rabbit clots. However, reactivity was restored to rabbit blood if it was seeded, before clotting, with human DD covalently coupled to Sepharose beads. Thus, a rabbit model was developed in which blood was allowed to clot around DD-Sepharose beads introduced into the jugular vein. Gamma camera imaging showed that intact 131 I-labelled DD-3B6/22 localised to these clots within 24 h. Uptake at this time was 0.202%±0.012% injected dose per gram (%ID/g) compared with 0.086±0.018%ID/g after injection of control antibody. 131 I-labelled F(ab') 2 fragments of DD-3B6/22 allowed earlier scintigraphic detection of the clot which was evident 4 h after injection. Uptake in the clot at 24 h was 0.154±0.038% ID/g compared with 0.109±0.027% ID/g for a control F(ab') 2 . As antigen levels in the clot are estimated to be less than 300 μg DD, thus representing a very small human clot, the DD-3B6/22 Mab would appear to have a good potential for the sensitive detection of thrombi in a clinical setting. (orig.)

Application of 125I-labelled soluble proteins in the histoautoradiographic detection of antigen and antibodies in the spleen of rabbits during primary immune response

International Nuclear Information System (INIS)

Rodak, L.

1975-01-01

An autoradiographic method for detecting soluble antigen (chicken serum albumin, CSA) and specific antibodies in the spleen of rabbits during a primary immune response is described. The method consists of incubating sections from the spleen with 125 I-labelled IgG 2 anti CSA (for demonstration of antigen) or with 125 I-labelled antigen (for demonstration of specific antibodies). This treatment of histological sections combines the advantages and principles of the immunofluorescence technique with the possibility of evaluating the exact localization of the proteins by light microscopy in preparations stained with haematoxylin or methyl green-pyronin. The sensitivity of detection is very high: both antigen and antibodies could be demonstrated in the spleen follicles for as long as 42 days after the primary intravenous injection

New insights into the development of technetium-99m labelling kits based on monoclonal antibodies

Energy Technology Data Exchange (ETDEWEB)

Haase, B. [Hoechst AG, Werk Kalle-Albert, Wiesbaden (Germany)

1995-09-01

Two-vial antibody kits for tumour scintigraphy, detection of inflammation and scintigraphy of the bone marrow are freeze-dried preparation ready for labelling with {sup 99m}Tc according to the instructions for use. Experiences about possible influences of antibody structure, in vitro analytical methods (TLC and HPLC), different types of eluate ({sup 99}Tc : {sup 99m}Tc ratios), sampling times, activity range, ratio between protein amount and activity as well as tin(II) amounts on radiochemical purity are described or discussed on an experimental basis. In a special case, {sup 99m}Tc Mab BW 250/183 suffered from an In vitro effect during quality control (only TLC) which gave false increased values for {sup 99m}Tc- pertechnetate. 3 refs., 3 tabs., 1 fig.

A new application of scanning electrochemical microscopy for the label-free interrogation of antibody-antigen interactions

Energy Technology Data Exchange (ETDEWEB)

Holmes, Joanne L.; Davis, Frank; Collyer, Stuart D. [Cranfield Health, Cranfield University, Cranfield, MK43 0AL (United Kingdom); Higson, Seamus P.J., E-mail: s.p.j.higson@cranfield.ac.uk [Cranfield Health, Cranfield University, Cranfield, MK43 0AL (United Kingdom)

2011-03-18

Within this work we present a 'proof of principle' study for the use of scanning electrochemical microscopy (SECM) to detect and image biomolecular interactions in a label-free assay as a potential alternative to current fluorescence techniques. Screen-printed carbon electrodes were used as the substrate for the deposition of a dotted array, where the dots consist of biotinylated polyethyleneimine. These were then further derivatised, first with neutravidin and then with a biotinylated antibody to the protein neuron specific enolase (NSE). SECM using a ferrocene carboxylic acid mediator showed clear differences between the array and the surrounding unmodified carbon. Imaging of the arrays before and following exposure to various concentrations of the antigen showed clear evidence for specific binding of the NSE antigen to the antibody derivatised dots. Non-specific binding was quantified. Control experiments with other proteins showed only non-specific binding across the whole of the substrate, thereby confirming that specific binding does occur between the antibody and antigen at the surface of the dots. Binding of the antigen was accompanied by a measured increase in current response, which may be explained in terms of protein electrostatic interaction and hydrophobic interactions to the mediator, thereby increasing the localised mediator flux. A calibration curve was obtained between 500 fg mL{sup -1} to 200 pg mL{sup -1} NSE which demonstrated a logarithmic relationship between the current change upon binding and antigen concentration without the need for any labelling of the substrate.

Anti-transferrin receptor antibody and antibody-drug conjugates cross the blood-brain barrier

International Nuclear Information System (INIS)

Friden, P.M.; Walus, L.R.; Musso, G.F.; Taylor, M.A.; Malfroy, B.; Starzyk, R.M.

1991-01-01

Delivery of nonlipophilic drugs to the brain is hindered by the tightly apposed capillary endothelial cells that make up the blood-brain barrier. The authors have examined the ability of a monoclonal antibody (OX-26), which recognizes the rat transferrin receptor, to function as a carrier for the delivery of drugs across the blood-brain barrier. This antibody, which was previously shown to bind preferentially to capillary endothelial cells in the brain after intravenous administration, labels the entire cerebrovascular bed in a dose-dependent manner. The initially uniform labeling of brain capillaries becomes extremely punctate ∼ 4 hr after injection, suggesting a time-dependent sequestering of the antibody. Capillary-depletion experiments, in which the brain is separated into capillary and parenchymal fractions, show a time-dependent migration of radiolabeled antibody from the capillaries into the brain parenchyma, which is consistent with the transcytosis of compounds across the blood-brain barrier. Antibody-methotrexate conjugates were tested in vivo to assess the carrier ability of this antibody. Immunohistochemical staining for either component of an OX-26-methotrexate conjugate revealed patterns of cerebrovascular labeling identical to those observed with the unaltered antibody. Accumulation of radiolabeled methotrexate in the brain parenchyma is greatly enhanced when the drug is conjugated to OX-26

In vitro evaluation of avidin antibody pretargeting using 211At-labeled and biotinylated poly-L-lysine as effector molecule

DEFF Research Database (Denmark)

Frost, Sofia H L; Jensen, Holger Lau; Lindegren, Sture

2010-01-01

Pretargeting is an approach for enhancing the therapeutic index of radioimmunotherapy by separating the administrations of tumor-targeting substance and radiolabel. In this study, a pretargeting model system of avidin-conjugated monoclonal antibody trastuzumab and biotinylated, (211)At-labeled poly...

Human breast tumor imaging using 111In labeled monoclonal antibody: Anthymic mouse model

International Nuclear Information System (INIS)

Ban An Khaw; Massachusetts General Hospital, Boston; Bailes, J.S.; Schneider, S.L.; Lancaster, J.; Lasher, J.C.; McGuire, W.L.; Powers, J.; Strauss, H.W.

1988-01-01

The monoclonal antibody (MoAb) 323/A3, an IgG1, was raised against the human breast tumor cell line MCF-7 and recognized a 43 Kd membrane associated glycoprotein. Histochemical studies with the antibody detected 75% of metastatic lymph nodes, 59% of primary breast tumors, and showed some staining in 20% of benign breast lesions. For radionuclide imaging, the MoAb 323/A3 was labeled with both 125 I and 111 In, via covalently coupled diethylenetriaminepentaacetic acid (DTPA) by the mixed anhydride method. The antibody activity of the DTPA modified 323/A3 was assessed by an immunoassay using viable and fixed MCF-7 target cells. Male athymic nude mice bearing BT-20 human mammary tumors were injected with dual 125 I/ 111 In labeled DTPA 323/A3 via the tail veins. The animals were imaged with a gamma camera equipped with a pinhole collimator at 1-3 h, 1, 2, 3, 4 and 5 days after the tracer administration. On day 5 or 6, the animals were killed, and the biodistribution of the radiotracers was determined for the blood, thyroid, heart, lungs, liver, spleen, kidneys, gastro-intestinal tract and tumor. Target to blood ratio at 6 days for the 111 In tracer was 24:1 in the group with a mean tumor weight of 0.492 g, and 13:1 in another group with a mean tumor weight of 0.1906 g (day 5). However, the 125 I activity showed only 3.6:1 and 5.4:1 target to blood ratios in the corresponding groups. The larger tumors localized less 111 I tracer (27.13%±7.57% injected dose/g, Mean±SD) than the smaller tumors (52.75%±22.25% ID/g). Analysis of the gamma images showed that the maximum tracer concentration occurred in the tumors at about 2 to 3 days after intravenous tracer administration. The excellent tumor resolution observed with BT-20 tumors may be due to increased 43 Kd glycoprotein antigen density in this tumor cell line. (orig.)

166Ho and 90Y labeled 6D2 monoclonal antibody for targeted radiotherapy of melanoma: Comparison with 188Re radiolabel

International Nuclear Information System (INIS)

Thompson, S.; Ballard, B.; Jiang, Z.; Revskaya, E.; Sisay, N.; Miller, W.H.; Cutler, C.S.; Dadachova, E.; Francesconi, L.C.

2014-01-01

Introduction: An approach to radioimmunotherapy (RIT) of metastatic melanoma is the targeting of melanin pigment with monoclonal antibodies (mAbs) to melanin radiolabeled with therapeutic radionuclides. The proof of principle experiments were performed using a melanin-binding antibody 6D2 of IgM isotype radiolabeled with a β emitter 188 Re and demonstrated the inhibition of tumor growth. In this study we investigated the efficacy of 6D2 antibody radiolabeled with two other longer lived β emitters 90 Y and 166 Ho in treatment of experimental melanoma, with the objective to find a possible correlation between the efficacy and half-life of the radioisotopes which possess high energy β (E max > 1.5 MeV) emission properties. Methods: 6D2 was radiolabeled with longer lived β emitters 90 Y and 166 Ho in treatment of experimental melanoma in A2058 melanoma tumor-bearing nude mice. The immunoreactivity of the radiolabeled 6D2 mAb, its in vitro binding to the MNT1 human melanoma cells, the biodistribution and therapy in A2058 human melanoma bearing nude mice as well as dosimetry calculations were performed. Results: When labeled with the longer lived 90 Y radionuclide, the 6D2 mAb did not produce any therapeutic effect in tumor bearing mice while the reduction of the tumor growth by 166 Ho-6D2 was very similar to the previously reported therapy results for 188 Re-6D2. In addition, 166 Ho-labeled mAb produced the therapeutic effect on the tumor without any toxic effects while the administration of the 90 Y-labeled radioconjugate was toxic to mice with no appreciable anti-tumor effect. Conclusions: 166 Ho-labeled mAb to melanin produced some therapeutic effect on the tumor without any toxic effects while the administration of the 90 Y-labeled radioconjugate was toxic to mice with no appreciable anti-tumor effect. We concluded that the serum half-life of the 6D2 carrier antibody matched well the physical half-life of 166 Ho to deliver the tumoricidal absorbed dose to the

Thrombus imaging with [sup 99m]Tc-HMPAO-labeled platelets and [sup 111]In-labeled monoclonal antifibrin antibodies

Energy Technology Data Exchange (ETDEWEB)

Vorne, M.S.; Honkanen, T.T.; Lantto, T.J.; Laitinen, R.O.; Karppinen, K.J.; Jauhola, S.V. (Depts. of Nuclear Medicine and Diagnostic Radiology, Paeijaet-Haeme Central Hospital, Lahti (Finland))

1993-01-01

Eighteen patients with suspicion of deep venous thrombosis (DVT) in the lower extremities were imaged both with autologous [sup 99m]Tc-HMPAO-labeled platelets (Tc-PLT) and [sup 111]In-labeled monoclonal antifibrin antibodies (In-MoAbs) on the same day. Precence or absence of thrombosis was verified by venography. Tc-PLT was given i.v. followed after 30 min by In-MoAbs. Anterior and posterior projections of the lower extremities were obtained with a large field-of-view gamma camera at 5 to 25 min, 2 h, 4 to 6 h, and 20 h after administration of the marker. Both Tc-PLT and In-MoAbs detected DVT well but less frequently than venography. Thrombi were visualized at 2 to 4 h after injection. The quality of images was better with Tc-PLT than with In-MoAbs. In the patients treated during the study, heparin significantly (p< 0.01) inhibited the uptake of Tc-PLT but not of In-MoAbs. We conclude that both Tc-PLT and In-MoAbs are suitable agents for the detection of DVT especially in patients without anticoagulation. (orig.).

Basic evaluation of 67Ga labeled digoxin derivative as a metal-labeled bifunctional radiopharmaceutical

International Nuclear Information System (INIS)

Fujibayashi, Yasuhisa; Konishi, Junji; Takemura, Yasutaka; Taniuchi, Hideyuki; Iijima, Naoko; Yokoyama, Akira.

1993-01-01

To develop metal-labeled digoxin radiopharmaceuticals with affinity with anti-digoxin antibody as well as Na + , K + -ATPase, a digoxin derivative conjugated with deferoxamine was synthesized. The derivative had a high binding affinity with 67 Ga at deferoxamine introduced to the terminal sugar ring of digoxin. The 67 Ga labeled digoxin derivative showed enough in vitro binding affinity and selectivity to anti-digoxin antibody as well as Na + , K + -ATPase. The 67 Ga labeled digoxin derivative is considered to be a potential metal-labeled bifunctional radiopharmaceutical for digoxin RIA as well as myocardial Na + , K + -ATPase imaging. (author)

Country report: Germany. Preclinical evaluation of Y-90 labelled Rituximab and ERIC-1, two antibodies for tumor therapy

Energy Technology Data Exchange (ETDEWEB)

Schomäcker, Klaus; Fischer, Thomas [Department of Nuclear Medicine, University of Cologne, Cologne (Germany)

2010-07-01

This project focuses on harnessing the great potential of radionuclide therapy, using various different vehicles to transport radionuclides into tumor tissues. A central aim of the project will be to manufacture specific vehicle molecules whose tumor affinity and suitability for radioactive coupling have already been proven through laboratory trials on animals and cell cultures at the Department of Nuclear Medicine, University of Cologne and to label it with Y- 90. The vectors to be used to transport radionuclides into tumor tissue for treatment are antibodies against lymphomas and neuroblastomas. The technology applied for coupling Y-90 to various antibodies has been developed to a high level in Cologne and is now ready to be transferred and adapted to GMP (Good Manufacturing Practice) conditions. The antibody against NHL can be acquired commercially and must then be modified for binding to the therapeutically active nuclide Y-90. Similarly, the antibody against neuroblastoma must also be modified to bind to Y-90 but is produced in Cologne. To improve the therapeutic value of antibodies we tried to introduce the pretargeting method.

Country report: Germany. Preclinical evaluation of Y-90 labelled Rituximab and ERIC-1, two antibodies for tumor therapy

International Nuclear Information System (INIS)

Schomäcker, Klaus; Fischer, Thomas

2010-01-01

This project focuses on harnessing the great potential of radionuclide therapy, using various different vehicles to transport radionuclides into tumor tissues. A central aim of the project will be to manufacture specific vehicle molecules whose tumor affinity and suitability for radioactive coupling have already been proven through laboratory trials on animals and cell cultures at the Department of Nuclear Medicine, University of Cologne and to label it with Y- 90. The vectors to be used to transport radionuclides into tumor tissue for treatment are antibodies against lymphomas and neuroblastomas. The technology applied for coupling Y-90 to various antibodies has been developed to a high level in Cologne and is now ready to be transferred and adapted to GMP (Good Manufacturing Practice) conditions. The antibody against NHL can be acquired commercially and must then be modified for binding to the therapeutically active nuclide Y-90. Similarly, the antibody against neuroblastoma must also be modified to bind to Y-90 but is produced in Cologne. To improve the therapeutic value of antibodies we tried to introduce the pretargeting method

Sequential radioimmunotherapy with 177Lu- and 211At-labeled monoclonal antibody BR96 in a syngeneic rat colon carcinoma model

DEFF Research Database (Denmark)

Eriksson, Sophie E; Elgström, Erika; Bäck, Tom

2014-01-01

for small, established tumors. A combination of such radionuclides may be successful in regimens of radioimmunotherapy. In this study, rats were treated by sequential administration of first a 177Lu-labeled antibody, followed by a 211At-labeled antibody 25 days later. METHODS: Rats bearing solid colon...... carcinoma tumors were treated with 400 MBq/kg body weight 177Lu-BR96. After 25 days, three groups of animals were given either 5 or 10 MBq/kg body weight of 211At-BR96 simultaneously with or without a blocking agent reducing halogen uptake in normal tissues. Control animals were not given any 211At-BR96....... The rats suffered from reversible myelotoxicity after treatment. CONCLUSIONS: Sequential administration of 177Lu-BR96 and 211At-BR96 resulted in tolerable toxicity providing halogen blocking but did not enhance the therapeutic effect....

90Nb: potential radionuclide for application in immuno-PET. Development of appropriate production strategy and first in vivo evaluation of 90Nb-labeled monoclonal antibody

International Nuclear Information System (INIS)

Radchenko, Valery

2013-01-01

Nuclear medicine is a modern and highly effective tool for the detection and treatment of oncological disease. Molecular imaging based on radiotracers includes single photon emission tomography (SPECT) and positron emission tomography (PET), which provide non-invasive tumor visualization on nano- and picomolar level, respectively. Currently, many novel tracers for more precise discovery of small tumors and metastases have been introduced and are under investigation. Many of them are protein-based biomolecules which nature herself produces as antigens for the eradication of tumor cells. Antibodies and antibody fragments play an important role in tumor diagnostics and treatment. PET imaging with antibodies and antibody fragments is called immuno-PET. The main issue that needs to be addressed is that appropriate radiotracers with half-lives related to the half-lives of biomolecules are needed. The development of novel radiotracers is a multistep, complicated task. This task includes the evaluation of production, separation and labeling strategy for chosen radionuclide. Finally, the biomolecule-radionuclide complex should be stable in time. An equally important factor is the economic suitability of the production strategy, which will lead to a key decision for future application of the developed radionuclide. In recent work, 90 Nb has been proposed as a potential candidate for application in immuno-PET. Its half-life of 14.6 hours is suitable for application with antibody fragments and some intact antibodies. 90 Nb has a relatively high positron branching of 53% and an optimal energy of β + emission of 0.35 MeV that can provide high quality of imaging with low dose of used radionuclide. First proof-of-principle studies have shown that 90 Nb: (i) can be produced in sufficient amount and purity by proton bombardment of natural zirconium target (ii) can be isolated from target material with appropriate radiochemical purity (iii) may be used for labeling of monoclonal

Technetium labeling of monoclonal antibodies with functionalized BATOs. 1. TcCl(DMG)3PITC.

Science.gov (United States)

Linder, K E; Wen, M D; Nowotnik, D P; Malley, M F; Gougoutas, J Z; Nunn, A D; Eckelman, W C

1991-01-01

BATO (boronic acid adduct of technetium dioximes) complexes, TcCl(dioxime)3BR, were prepared in which the boron substituent (R) was the protein-reactive m-phenyl isothiocyanate (PITC). The 99TcCl(dioxime)3PITC complexes [dioxime = dimethylglyoxime (DMG) or cyclohexanedione dioxime (CDO)] were prepared from 99Tc(dioxime)3(mu-OH)SnCl3 and characterized. The X-ray crystal structure of 99TcCl(DMG)3PITC was determined. The 99mTc complexes were prepared from 99mTcO4- in a process using a freeze-dried kit, either in a one-step procedure or via 99mTcCl(dioxime)3. Initial labeling studies with 99mTcCl(dioxime)3PITC were performed on glycine and polylysine and, subsequently, on mouse IgG and the B72.3 monoclonal antibody. Covalent attachment of 99mTcCl(DMG)3PITC to B72.3 was demonstrated by SDS-PAGE electrophoresis. B72.3 labeled with 99mTcCl(DMG)3PITC displayed high binding to a TAG 72 affinity column and had a distribution in normal mice similar to that reported for iodine-labeled B72.3.

Scintigraphy with /sup 111/In-labeled antimyosin F(ab)/sub 2/ monoclonal antibody and /sup 99m/Tc-pyrophosphate in rhabdomyolysis

Energy Technology Data Exchange (ETDEWEB)

Krause, T.; Schuemichen, C.; Hohenloser, S.; Kasper, W.; Meinertz, T.

1988-02-01

A report is presented of the scintigraphic diagnosis of a generalized rhabdomyolysis with myocardial involvement using /sup 111/In labelled antimyosin F(ab)/sub 2/ monoclonal antibodies as compared to /sup 99m/Tc pyrophosphate.

Abnormally phosphorylated tau protein in senile dementia of Lewy body type and Alzheimer disease: evidence that the disorders are distinct.

Science.gov (United States)

Strong, C; Anderton, B H; Perry, R H; Perry, E K; Ince, P G; Lovestone, S

1995-01-01

The relationship between Alzheimer disease (AD) and dementia with Lewy bodies (senile dementia Lewy body type, or SDLT) and dementia in Parkinson's disease is unclear. AD pathology is characterised by both amyloid deposition and abnormal phosphorylation of tau in paired helical filaments (PHF-tau). In AD, abnormally phosphorylated PHF-tau is present in neurofibrillary tangles, in neuritic processes of senile plaques, and also in neuropil threads dispersed throughout the cerebral cortex. Cortical homogenates from 12 cases each of AD and SDLT, 13 cases of Parkinson's disease, and 11 normal controls were examined by Western blot analysis with antibodies that detect PHF-tau. No PHF-tau was found in Parkinson's disease or control cortex. No PHF-tau was found in SDLT cases without histological evidence of tangles. PHF-tau was detectable in SDLT cases with a low density of tangles, and large amounts of PHF-tau were present in AD cases. This study demonstrates that abnormally phosphorylated PHF-tau is only present where tangles are found and not in SDLT cases without tangles or with only occasional tangles. It is concluded that Lewy body dementias are distinct at a molecular level from AD.

An Antibody-Immobilized Silica Inverse Opal Nanostructure for Label-Free Optical Biosensors

Directory of Open Access Journals (Sweden)

Wang Sik Lee

2018-01-01

Full Text Available Three-dimensional SiO2-based inverse opal (SiO2-IO nanostructures were prepared for use as biosensors. SiO2-IO was fabricated by vertical deposition and calcination processes. Antibodies were immobilized on the surface of SiO2-IO using 3-aminopropyl trimethoxysilane (APTMS, a succinimidyl-[(N-maleimidopropionamido-tetraethyleneglycol] ester (NHS-PEG4-maleimide cross-linker, and protein G. The highly accessible surface and porous structure of SiO2-IO were beneficial for capturing influenza viruses on the antibody-immobilized surfaces. Moreover, as the binding leads to the redshift of the reflectance peak, the influenza virus could be detected by simply monitoring the change in the reflectance spectrum without labeling. SiO2-IO showed high sensitivity in the range of 103–105 plaque forming unit (PFU and high specificity to the influenza A (H1N1 virus. Due to its structural and optical properties, SiO2-IO is a promising material for the detection of the influenza virus. Our study provides a generalized sensing platform for biohazards as various sensing strategies can be employed through the surface functionalization of three-dimensional nanostructures.

An Antibody-Immobilized Silica Inverse Opal Nanostructure for Label-Free Optical Biosensors.

Science.gov (United States)

Lee, Wang Sik; Kang, Taejoon; Kim, Shin-Hyun; Jeong, Jinyoung

2018-01-20

Three-dimensional SiO₂-based inverse opal (SiO₂-IO) nanostructures were prepared for use as biosensors. SiO₂-IO was fabricated by vertical deposition and calcination processes. Antibodies were immobilized on the surface of SiO₂-IO using 3-aminopropyl trimethoxysilane (APTMS), a succinimidyl-[(N-maleimidopropionamido)-tetraethyleneglycol] ester (NHS-PEG₄-maleimide) cross-linker, and protein G. The highly accessible surface and porous structure of SiO₂-IO were beneficial for capturing influenza viruses on the antibody-immobilized surfaces. Moreover, as the binding leads to the redshift of the reflectance peak, the influenza virus could be detected by simply monitoring the change in the reflectance spectrum without labeling. SiO₂-IO showed high sensitivity in the range of 10³-10⁵ plaque forming unit (PFU) and high specificity to the influenza A (H1N1) virus. Due to its structural and optical properties, SiO₂-IO is a promising material for the detection of the influenza virus. Our study provides a generalized sensing platform for biohazards as various sensing strategies can be employed through the surface functionalization of three-dimensional nanostructures.

Plasma Triglyceride Levels May Be Modulated by Gene Expression of IQCJ, NXPH1, PHF17 and MYB in Humans

Directory of Open Access Journals (Sweden)

Bastien Vallée Marcotte

2017-01-01

Full Text Available A genome-wide association study (GWAS by our group identified loci associated with the plasma triglyceride (TG response to ω-3 fatty acid (FA supplementation in IQCJ, NXPH1, PHF17 and MYB. Our aim is to investigate potential mechanisms underlying the associations between single nucleotide polymorphisms (SNPs in the four genes and TG levels following ω-3 FA supplementation. 208 subjects received 3 g/day of ω-3 FA (1.9–2.2 g of EPA and 1.1 g of docosahexaenoic acid (DHA for six weeks. Plasma TG were measured before and after the intervention. 67 SNPs were selected to increase the density of markers near GWAS hits. Genome-wide expression and methylation analyses were conducted on respectively 30 and 35 participants’ blood sample together with in silico analyses. Two SNPs of IQCJ showed different affinities to splice sites depending on alleles. Expression levels were influenced by genotype for one SNP in NXPH1 and one in MYB. Associations between 12 tagged SNPs of IQCJ, 26 of NXPH1, seven of PHF17 and four of MYB and gene-specific CpG site methylation levels were found. The response of plasma TG to ω-3 FA supplementation may be modulated by the effect of DNA methylation on expression levels of genes revealed by GWAS.

Radioiodinated iodobenzoyl conjugates of a monoclonal antibody Fab fragment. In vivo comparisons with chloramine-T-labeled Fab

International Nuclear Information System (INIS)

Wilbur, D.S.; Hadley, S.W.; Grant, L.M.; Hylarides, M.D.

1991-01-01

A comparative investigation of the biodistributions of radioiodinated p- and m-iodobenzoyl conjugates of a monoclonal antibody Fab fragment, NR-LU-10 Fab, and the same antibody Fab fragment radioiodinated by the chloramine-T (ChT) method has been carried out in mice. Coinjected, dual-isotope studies in athymic mice with tumor xenografts have demonstrated that there are only minor differences in the in vivo distributions of the iodobenzoyl-labeled Fabs, except in the excretory organs, kidneys, and intestines, where major differences were observed. Similarly, coinjection of either the p-iodobenzoyl or m-iodobenzoyl conjugate of NR-LU-10 Fab with the Fab radioiodinated with ChT/radioiodide into BALB/c mice provided additional data that indicated that the two iodobenzoyl conjugates distributed similar in a number of selected tissues. The tissue-distribution differences of the regioisomeric iodobenzoyl conjugates in relation to the ChT-radioiodinated Fab were large for the stomach and neck, consistent with previous studies. The most notable difference between the two iodobenzoyl conjugates was the kidney activity, where the m-iodobenzoyl conjugate was similar to the directly labeled Fab, but the p-iodobenzoyl-conjugated Fab was higher by nearly a factor of 2

AbetaPP induces cdk5-dependent tau hyperphosphorylation in transgenic mice Tg2576.

Science.gov (United States)

Otth, Carola; Concha, Ilona I; Arendt, Thomas; Stieler, Jens; Schliebs, Reinhard; González-Billault, Christian; Maccioni, Ricardo B

2002-10-01

Previous studies of Abeta-induced neuronal damage of hippocampal cells in culture have provided strong evidence that deregulation of the Cdk5/p35 kinase system is involved in the neurodegeneration pathway. Cdk5 inhibitors and antisense probes neuroprotected hippocampal cells against the neurotoxic action of Abeta. To further investigate the mechanisms underlying the participation of Cdk5 in neuronal degeneration, the transgenic mouse containing the Swedish mutations, Tg2576, was used as an animal model. Immunocytochemical studies using anti-Abeta(1-17) antibody evidenced the presence of labeled small-clustered core plaques in the hippocampus and cortex of 18-month-old transgenic mice brains. The loss of granular cells without a compressed appearance was detected in the vicinity of the cores in the dentate gyrus of the hippocampus. Immunostaining of Tg2576 brain sections with antibodies AT8, PHF1 and GFAP labeled punctuate dystrophic neurites in and around the amyloid core. Reactive astrogliosis around the plaques in the hippocampus was also observed. Studies at the molecular level showed differences in the expression of the truncated Cdk5 activator p25 in the transgenic animal, as compared with wild type controls. However no differences in Cdk5 levels were detected, thus corroborating previous cellular findings. Interestingly, hyperphosphorylated tau epitopes were substantially increased as assessed with the AT8 and PHF1 antibodies, in agreement with the observation of a p25 increase in the transgenic animal. These observations strongly suggest that the increased exposure of Alzheimer's type tau phosphoepitopes in the transgenic mice correlated with deregulation of Cdk5 leading to an increase in p25 levels. These studies also provide further evidence on the links between extraneuronal amyloid deposition and tau pathology.

Basic evaluation of [sup 67]Ga labeled digoxin derivative as a metal-labeled bifunctional radiopharmaceutical

Energy Technology Data Exchange (ETDEWEB)

Fujibayashi, Yasuhisa; Konishi, Junji (Kyoto Univ. (Japan). Faculty of Medicine); Takemura, Yasutaka; Taniuchi, Hideyuki; Iijima, Naoko; Yokoyama, Akira

1993-11-01

To develop metal-labeled digoxin radiopharmaceuticals with affinity with anti-digoxin antibody as well as Na[sup +], K[sup +]-ATPase, a digoxin derivative conjugated with deferoxamine was synthesized. The derivative had a high binding affinity with [sup 67]Ga at deferoxamine introduced to the terminal sugar ring of digoxin. The [sup 67]Ga labeled digoxin derivative showed enough in vitro binding affinity and selectivity to anti-digoxin antibody as well as Na[sup +], K[sup +]-ATPase. The [sup 67]Ga labeled digoxin derivative is considered to be a potential metal-labeled bifunctional radiopharmaceutical for digoxin RIA as well as myocardial Na[sup +], K[sup +]-ATPase imaging. (author).

In vitro measurement of avidity of radioiodinated antibodies

International Nuclear Information System (INIS)

Badger, C.C.; Krohn, K.A.; Bernstein, I.D.

1987-01-01

A determination of the ability of radiolabeled antibodies to bind to their target antigen is an essential step in the initial selection of antibodies for clinical use as well as a quality control measure. In our studies of the 131 I-labeled anti-Thy 1.1 antibody treatment of murine lymphoma, we have used cell binding assays with a combination of Lineweaver-Burk analysis to determine immunoreactivity and Scatchard analysis to determine antibody avidity. Both assays were systematically influenced by target cell fixation and measurement of avidity was dependent on immunoreactivity. For 131 I-labeled anti-Thy 1.1 antibody, avidity was a much more sensitive indicator of iodination damage and predictor of in vivo behavior than was immunoreactivity, while for other antibodies immunoreactivity has been a better indicator of labeling damage. Thus, immunoreactivity and avidity assays are complementary and knowledge of both factors is required for the design of sensitive quality control procedures for radiolabeled antibodies. (author)

In vivo amyloid-β imaging in the APPPS1-21 transgenic mouse model with a 89Zr- labeled monoclonal antibody.

Directory of Open Access Journals (Sweden)

Ann-Marie eWaldron

2016-03-01

Full Text Available Introduction: The accumulation of amyloid-β is a pathological hallmark of Alzheimer’s disease and is a target for molecular imaging probes to aid in diagnosis and disease monitoring. This study evaluated the feasibility of using a radiolabeled monoclonal anti-amyloid-β antibody (JRF/AβN/25 to non-invasively assess amyloid-β burden in aged transgenic mice (APPPS1-21 with μPET imaging.Methods: We investigated the antibody JRF/AβN/25 that binds to full-length Aβ. JRF/AβN/25 was radiolabeled with a [89Zr]-desferal chelate and intravenously injected into 12-13 month aged APPPS1-21 mice and their wild-type (WT controls. Mice underwent in vivo μPET imaging at 2, 4 and 7 days post injection and were sacrificed at the end of each time point to assess brain penetrance, plaque labeling, biodistribution and tracer stability. To confirm imaging specificity we also evaluated brain uptake of a non-amyloid targeting [89Zr]-labeled antibody (Trastuzumab as a negative control, additionally we performed a competitive blocking study with non-radiolabeled Df-Bz-JRF/AβN/25 and finally we assessed the possible confounding effects of blood retention. Results: Voxel-wise analysis of μPET data demonstrated significant [89Zr]-Df-Bz-JRF/AβN/25 retention in APPPS1-21 mice at all time points investigated. With ex vivo measures of radioactivity, significantly higher retention of [89Zr]-Df-Bz-JRF/AβN/25 was found at 4 and 7 day pi in APPPS1-21 mice. Despite the observed genotypic differences, comparisons with immunohistochemistry revealed that in vivo plaque labeling was low. Furthermore, pre-treatment with Df-Bz-JRF/AβN/25 only partially blocked [89Zr]-Df-Bz-JRF/AβN/25 uptake indicative of a high contribution of non-specific binding. Conclusion: Amyloid plaques were detected in vivo with a radiolabeled monoclonal anti-amyloid antibody. The low brain penetrance of the antibodies in addition to non-specific binding prevented an accurate estimation of plaque

The biodistribution of mouse monoclonal antibody ONS-M21 and the application for imaging diagnosis with its humanized antibody

International Nuclear Information System (INIS)

Ohkawa, Motohisa

1997-01-01

The mouse monoclonal antibody ONS-M21 combines with medulloblastomas and several gliomas specifically. And also we had already produced it humanized antibody. This study investigated the in vivo biodistribution of ONS-M21 and the application for imaging diagnosis using its humanized antibody. The nude mice (BALB/c nu/nu) bearing human medulloblastoma ONS-76 cells subcutaneously were injected 125 I-labeled ONS-M21 antibody via their tail vein. The radioactivities of their normal organs and the s.c. tumor were counted with γ-counter. And their autoradiograph (ARG) 6 hours after this administration was compared with gadolinium enhanced T1-weighted magnetic resonance image (Gd-T1-MRI). The brain tumor models transplanted ONS-76 cells stereotaxically was made by the nude rats (F344/N Jcl-rnu). And compared with MRI and ARG after the administration of 125 I-labeled humanized antibody into these models. The ARG indicated the accumulation of 125I -labeled ONS-M21 in the tumors which was detected by Gd-T1-MRI study. In this study, 125 I-labeled ONS-M21 remained in the tumor longer than the other normal organs. The mouse monoclonal antibody ONS-M21 have specific affinity for ONS-76 tumor in vivo. Then this humanized antibody is considerable to apply the imaging diagnosis of the malignant brain tumors. (author)

Labelling and standardizing some pituitary hormones for radioimmunoassay

International Nuclear Information System (INIS)

Kim, Y.S.

1976-11-01

Optimum conditions for efficient 125 I labelling of human follicle stimulating hormone (FSH) and human chorionic gonadotropin (HCG) using chloramine-T have been established for radioimmunoassay (RIA). The amount of the hormone, chloramine-T, 125 I, and the reaction time were, respetively, controlled evaluating the yield and the bindability of the labelled hormone to its antibody. To measure the bindability, the labelled hormone was incubated together with its antibody for a definite temperature. In the separation of the free hormone (F) from the antibody bound (B), a double antibody technique was applied comparing with the chromatoelectrophoresis. For the efficient separation of the labelled hormone, two methods of separation such as gel filtration and gel electrophoresis were compared in the sensitivity and in the immunological activity points of view. Experiments for the production of HCG antibody were also conducted. The produced antisera were tested in two ways; i.e., the incubation test with the labelled hormone, and the Ouchterlony test. Using the produced anti-HCG serum and the purchased anti-FSH serum, standard dose-response curves were plotted correlating with the international standard preparation of the hormones

Development of instant kits 99Tcm-labelling of anti-CEA antibody and hIgG for scintigraphy

International Nuclear Information System (INIS)

Boonkittcharoen, V.

1998-01-01

99 Tc m -labelled monoclonal antibodies (MAbs) and human immunoglobulins (hIgG) have recently emerged as a new class of site specific radiopharmaceuticals. The role of 99 Tc m -labelled MAbs particularly anti-CEA IgG in tumour imaging has essentially established for early revealing of occult lesions in patients. Superiority of the method over X ray CT has been addressed for its capability in differentiating post-operation fibrosis from viable tumour. At present data, instant kits for preparation of this particular class of radiopharmaceuticals can be obtained from commercial sources but unfortunately at high prices. This prohibits the use of these promising diagnostic agents in developing country like Thailand. Under the assistance from IAEA through a research coordinating program, we worked on the 99 Tc m -radiochemistry in immunoglobulin labelling to establish the knowledge and acquire the know how in the development of in-house instant kits at low cost to serve the local nuclear medicine clinics in diagnosis of infectious and neoplastic diseases

Bioactivity assays and application of 125I labeled human mouse chimeric anti-CD22 monoclonal antibody SM03

International Nuclear Information System (INIS)

Lu Pingping; Meng Zhiyun; Dou Guifang; Wu Yingliang; Wang Minwei

2008-01-01

To investigate the bioactivity and application of 125 I labeled human mouse chimeric monoclonal SM03, SM03 was labeled with 125 I using Indogen method. The labeled mixture was purified by Sephacryl S-300 HR separation chromospectry. The purity and concentration of separated fractions were determined by HPLC and Protein Assay Kit, respectively. Competitive binding method and ELISA method were used for bioactivity assays. 125 I-SM03 was applied to screen cell lines which express the most abundant CD22 antigen. The purity and recovery of 125 I-SM03 were >99% and >47%, respectively. The bioactivity of 125 I- SM03 and SM03 hasn't significant difference in statistics. Ramos cell line had the strongest special radioactivity when 125 I-SM03 bound with in Raji, Daudi and Ramos cell lines. Indogen method is a good way to label Human mouse chimeric anti-CD22 monoclonal antibody SM03 and the label will not affect the activity of SM03. The 125 I-SM03 not only can be used for detect agent, but also may be put into market for NHL therapy. (authors)

Thrombus imaging with indium-111 and iodine-131-labeled fibrin-specific monoclonal antibody and its F(ab')2 and Fab fragments

International Nuclear Information System (INIS)

Rosebrough, S.F.; Grossman, Z.D.; McAfee, J.G.

1988-01-01

We have previously reported successful imaging of fresh (2-4 hr old) and aged (1-5 days old) canine thrombi with 131 I-labeled intact monoclonal antibody (MAb) specific for fibrin. We now report thrombus imaging with 131 I-labeled F(ab')2 and Fab and 111 In-labeled intact MAb, F(ab')2, and Fab. Indium-111-labeled F(ab')2 proved to be the best imaging agent due to less nonspecific binding in the liver than whole IgG. Image quality was improved by the higher administered dose permissible with 111 In and its better physical characteristics for imaging, compared to 131 I. Immunofluorescence of fresh human histologic sections showed intact MAb and F(ab')2 binding to thrombi, pulmonary emboli, and atherosclerotic plaques, strengthening the feasibility of clinical thrombus imaging

Quantitative 89Zr immuno-PET for in vivo scouting of 90Y-labeled monoclonal antibodies in xenograft-bearing nude mice.

NARCIS (Netherlands)

Verel, I.; Visser, G.W.; Boellaard, R.; Boerman, O.C.; Eerd-Vismale, J.E.M. van; Snow, G.B.; Lammertsma, A.A.; Dongen, G.A.M.S. van

2003-01-01

Immuno-PET as a scouting procedure before radioimmunotherapy (RIT) aims at the confirmation of tumor targeting and the accurate estimation of radiation dose delivery to both tumor and normal tissues. Immuno-PET with (89)Zr-labeled monoclonal antibodies (mAbs) and (90)Y-mAb RIT might form such a

Radioimmunoscintigraphy with technetium-99m labelled monoclonal antibody, 1A3, in colorectal cancer

International Nuclear Information System (INIS)

Granowska, M.; Britton, K.E.; Mather, S.J.; Morris, G.; Ellison, D.; Soobramoney, S.; Talbot, I.C.; Northover, J.M.A.

1993-01-01

This study of radioimmunoscintigraphy (RIS) was primarily undertaken to determine how the imaging results related to surgical findings. Technetium-99m radiolabelled 1A3, a monoclonal antibody against a columnar cell surface antigen, was used. No adverse effects or thyroid uptake was observed in 127 studies. The 85 primary colorectal cancers were all image positive. In the assessment of recurrent tumour in the abdomen or pelvis, the accuracy was 33/35 (94%), including true-positive findings in some whose serum carcinoembryonic antigen was normal. There was a positive predictive value for abdominal or pelvic recurrence of 92% and a negative predictive value of 100%, at a prevalence of 66%. In those patients whose liver was able to be evaluated, the accuracy was 72/79 (91%). There was a positive predictive value for liver metastases of 88% and a negative predictive value of 93%, at a prelavence of 32%. The simple procedure for labelling antibody with 99m Tc and its ready availability allow a completed report to be given within 24 h of the request. (orig.)

The detection of ovarian cancer using 123I monoclonal antibody

International Nuclear Information System (INIS)

Granowska, M.; Britton, K.E.; Shepherd, J.

1984-01-01

The technique of the production of monoclonal antibodies is described. Antibodies show reactivity with epithelial surfaces of cancer of breast, colon and ovary. The iodogen reaction is used for labelling monoclonal antibodies with 123 I. Description of labelling technique and quality control. After intravenous injection of 74 MBq 123 I-labelled monoclonal antibody (0.5 mg) static camera images of the abdomen were recorded at 10 min, 4 and 22 hours in anterior and posterior position. 20 out of 22 patients with ovarian cancer with and without metastases were correctly diagnosed and confirmed at surgery. (author)

The clinical application of radioimmunoimaging with 99mTc labeled anti-CEA monoclonal antibody C50

International Nuclear Information System (INIS)

Jiang Ningyi; Sha Xiaozhen; Zhang Hua

1996-01-01

To evaluate the clinical value of the radioimmunoimaging (RII) for the diagnosis of tumor with 99m Tc labeled anti-CEA monoclonal antibody C50, C50 was labeled with 99m Tc using modified 2-mercaptoethanol method. 99m Tc-C50 RII was performed in 70 patients with tumor. All were pathologically proved after operation. The sensitivity of 99m Tc-C50 RII for tumor was 82.9%, the specificity was 86.2%, the false negative rate was 17.1%, and the false positive rate was 13.8%. The positive predictive value was 89.5%, the negative predictive value was 78.1%. The coincidence rates was 82.4%, 84.6% and 80.0% for the ovarial intestinal and lung tumor respectively. 99m Tc-C50 RII was useful in clinical diagnosis of tumor

Comparison of in-vivo kinetics of an antibody cocktail containing 131-iodine anti-CA-19/9 and 131-iodine anti-CEA with 111-indium labelled monoclonal anti-CA-19/9 using a tumor model in mice

International Nuclear Information System (INIS)

Koenig, S.; Orth, M.; Henze, E.

1993-01-01

In this study the potential diagnostic value of an 111-In-labelled CA-19/9-F (ab)-fragment was compared to that of an antibody cocktail of 131-iodine-labelled CA-19/9 and 131-iodine-labelled anti-CEA for identification of pancreas cancer by a nude mice model. 111-In-labelled CA-19/9 and the 131-iodine antibody cocktail were injected into 35 nude mice xenotransplantated with human pancreas cancer. Scintigrams were obtained and the relative distribution of activity in tumor and in several organs were determined by ROI-technique. These values were compared with the in vitro results of organ measurement after dissection of nude mice. Blood pool of 131-iodine-labelled antibodies showed only a nuclide accumulation in the thyroid because of very high rate of dejodination and missing blockade of thyroid. Other organs were not detectabel in scintigraphy because of high nucleotide accumulation of thyroid. The tumor-to-blood-ratio of organ-measurements was 18±4.3, kidneys-background-ratio 2.1±7.3, liver-background-ratio 5.8±2.0. These results are similar to those of 111-In-labelled fragments. Thus it is established that antibody cocktail had no essential advantage over singular antibody in mouse model. It gives a good tumor contrast with tumor-background-quotient of 15±7.4 measured by scintigraphy and tumor background-quotient 18±4.3 in-vitro-organ-measurement. (orig.) [de

Imaging of primary and metastatic colorectal carcinoma with monoclonal antibody 791T/36 and the therapeutic potential of antibody-drug conjugates

International Nuclear Information System (INIS)

Pimm, M.V.; Armitage, N.C.; Ballantyne, K.; Baldwin, R.W.; Perkins, A.C.; Durrant, L.G.; Garnett, M.C.; Hardcastle, J.D.

1987-01-01

Monoclonal antibody 791T/36, prepared against a tumor-associated 72,000 dalton glycoprotein, reacted with cells from primary and metastatic colorectal carcinomas. I-131 or In-111-labelled antibody localized in xenografts of colorectal carcinomas established from in vitro clonogenic populations. Clinically, with I-131-labelled antibody, 8/11 colonic tumors imaged positively. Imaging was negative in four patients with benign colon disease. 5/11 rectal tumors were positively imaged, but excreted I-131 in the bladder obscured tumors in several studies. In-111-labelled antibody gave superior images and positively imaged primary and metastatic sites in 13/14 patients. Prospectively in the detection of recurrent disease, I-131 or In-111-antibody detected 29/33 separate sites in 24 patients. Seven negative patients remain disease free. There were 3 false positives; overall sensitivity was 88%, with 70% specificity. Specific localization of radiolabel was confirmed immunochemically and by counting radioactivity in resected specimens. Antibody conjugates with methotrexate, vindesine and daunomycin retained drug activity and antibody function, including xenograft localization and conjugates were therapeutically effective against xenografts. 791T/36 antibody has potential for immunodetection of primary and recurrent colorectal carcinoma and for targeting of therapeutic agents

On the use of {sup 76}Br-labelled monoclonal antibodies for PET : Preclinical evaluation of halogenated antibodies for diagnosis and treatment of cancer

Energy Technology Data Exchange (ETDEWEB)

Hoeglund, Johanna

2002-07-01

Radioactive substances are used in vivo to localize and characterize malignant tumours, generally by scintigraphic methods. In this context positron emission tomography (PET) in combination with radiolabelled monoclonal antibodies (mAbs) may provide a sensitive and specific method for detection of cancer. Individual dose calculations, based on such PET measurements, may be carried out to predict the possible use of mAbs labelled with therapeutic nuclides. The positron emitter {sup 76}Br, with a half-life of 16 h, is a well-suited candidate for radiolabelling and PET imaging. One drawback of radio bromine is that bromide, the ultimate catabolite after degradation of brominated mAb, is only tardily excreted from the body and is evenly distributed throughout the extracellular space, thereby increasing the background radioactivity. The aim of this work was to produce {sup 76}Br-mAb preparations with high accumulation and retention in tumour tissue together with a quick clearance of {sup 76}Br-labelled catabolites. Furthermore, the possibility to use brominated or iodinated mAbs in combination with PET to predict {sup 211}At-mAb dosimetry was evaluated. Monoclonal Abs directed against colorectal cancer were labelled with {sup 76}Br using the direct Chloramine-T-method or indirectly by labelling the precursor molecule N-succinimidyl para-(tri-methylstannyl) benzoate with {sup 76}Br, which was subsequently conjugated to the mAbs. Monoclonal Ab A33 labelled with {sup 76}Br using the two labelling protocols was characterized in vitro and in vivo in a rat tumour xenograft model. The mAb A33 was also labelled with 125I for comparison. In addition, mAb A33 was labelled with {sup 211}At, 125I and {sup 76}Br using the indirect labelling protocol and the mAb pharmacokinetics was studied in normal rats in order to estimate if data from brominated or iodinated mAb could be used for dosimetry of {sup 211}At in healthy organs and tissue. In conclusion, both direct and indirect

Labelled antibody assays for measuring free triiodothyronine: evaluation and comparison with a labelled analog method

International Nuclear Information System (INIS)

Sapin, R.; Gasser, F.; Schlienger, J.L.; Chambron, J.

1993-01-01

We evaluated analytically and clinically two new one-step labelled antibody assays for measuring free triiodothyronine (FT3): the first, radiolabelled with 125 I, Amerlex-MAB (MAB) from Kodak diagnostic, and the second, labelled with peroxidase, Enzymum-test FT3 (BM) from Boehringer Mannheim adapted for the Boehringer ES 600 analyzer. The clinical results were compared with those obtained with a radiolabelled analog tracer kit, Amerlex-M (M) from Kodak diagnostic. The latter kit is known to give low FT3 results in sera with low albumin concentrations. Analytical performances of the automated method (BM) were better than those obtained with the manual method (MAB): intra-assay reproducibility (CV<3% vs CV about 5%), inter-assay reproducibility (CV<4% vs CV between 4 and 8%) and mean drift (+1.25% vs -4.3%). The detection limit was low for both kits (<1 pmol/l). In the euthyroid reference group (n = 98) we observed a significant difference between outpatient and hospitalized patient FT3 concentrations as measured with the M kit only. Clinical sensitivity for hyperthyroidism (n = 38) was better for the MAB (92%) than for the BM kit (76%). Specificity in euthyroid L-thyroxine (T4) treated patients (n = 26) was good for both kits (MAB: 92%; BM: 88%) . Hypoalbuminemia (n = 8) decreased FT3 results as follows: M, very significantly; BM, significantly; MAB, only slightly. In patients treated with amiodarone (n = 5), a drug known to lower the metabolic conversion of T4 to T3, the increase of the MAB FT3 results contrasted with the decrease of the BM and M results. In conclusion, results of the two new kits were not strongly influenced by hypoalbuminemia. The MAB results showing lack of decrease in patients with non-thyroidal illness without hypoalbuminemia and in amiodarone-treated patients were unexpected

Comparison of 5 Ki-67 antibodies regarding reproducibility and capacity to predict prognosis in breast cancer: does the antibody matter?

Science.gov (United States)

Ács, Balázs; Kulka, Janina; Kovács, Kristóf Attila; Teleki, Ivett; Tőkés, Anna-Mária; Meczker, Ágnes; Győrffy, Balázs; Madaras, Lilla; Krenács, Tibor; Szász, Attila Marcell

2017-07-01

Although several antibodies are available for immunohistochemical detection of Ki-67, even the most commonly used MIB-1 has not been validated yet. Our aim was to compare 5 commercially available antibodies for detection of Ki-67 in terms of agreement and their ability in predicting prognosis of breast cancer. Tissue microarrays were constructed from 378 breast cancer patients' representative formalin-fixed, paraffin-embedded tumor blocks. Five antibodies were used to detect Ki-67 expression: MIB-1 using chromogenic detection and immunofluorescent-labeled MIB-1, SP-6, 30-9, poly, and B56. Semiquantitative assessment was performed by 2 pathologists independently on digitized slides. To compare the 5 antibodies, intraclass correlation and concordance correlation coefficient were used. All the antibodies but immunofluorescent-labeled MIB-1 (at 20% and 30% thresholds, P=.993 and P=.342, respectively) and B56 (at 30% threshold, P=.288) separated high- and low-risk patient groups. However, there were a significant difference (P values for all comparisons≤.005) and a moderate concordance (intraclass correlation, 0.645) between their Ki-67 labeling index scores. The highest concordance was found between MIB-1 and poly (concordance correlation coefficient=0.785) antibodies. None of the antibodies except Ki-67 labeling index as detected by poly (P=.031) at 20% threshold and lymph node status (Pantibodies in their capacity to detect proliferating tumor cells and to separate low- and high-risk breast cancer patient groups. Copyright © 2017 Elsevier Inc. All rights reserved.

Studies of monoclonal antibodies IOR-CEA-1 and IOR-EGF/R3 labelled with {sup 99m}Tc; Estudo de marcacao dos anticorpos monoclonais IOR-CEA-1 e IOR-EGF/R3 com {sup 99m}Tc

Energy Technology Data Exchange (ETDEWEB)

Dias, Carla Roberta de Barros Rodrigues

2005-07-01

Nuclear Medicine is a speciality that uses radioisotopes for the diagnosis or treatment of diseases and it is considered one of the best tools among the diagnostic modalities for detection of cancer. {sup 99m}Tc is one of the main isotopes for labelling antibodies and in Nuclear Medicine in general, due to its adequate physical properties, availability and low cost. Labelled monoclonal antibodies have shown promising results for diagnosis and therapy of cancer and their use has brought great experimental and clinical advances in the field of oncology. The main clinical applications of immunoscintigraphy with monoclonal antibodies are staging and evaluation of tumoral reappearance. The antibodies employed in this work were: OIR-CEA-1, a murine monoclonal antibody that acts directly against CEA expressed in several neoplasia in particular those from the gastrointestinal tract (colorectal cancer) and IOR-EGF/R3, a murine monoclonal antibody that binds to the external domain of EGF-R and it has been used in the diagnosis of tumors of epithelial origin. The objectives of this work were the development and optimization of the reduction and purification processes, the radiolabelling techniques and quality control procedures (radiochemical, immunoreactivity and cystein challenge) and imaging studies of monoclonal antibodies OIR-CEA-1 and IOR-EGF/R3, using the simple, fast and efficient method of direct labelling of the antibody with {sup 99m}Tc. The final results was the definition of the best conditions for the preparation of lyophilized reactive kits of OIR-CEA-1 and IOR- EGF/R3 for an efficient diagnostic application in Nuclear Medicine. The most adequate conditions for the labelling of the antibodies were: 1.0 mg Ab, 29 {mu}L MDP, 3.0 {mu}g Sn{sup 2+}, 1 mL of {sup 99m}Tc and 30 min. reaction time. With these conditions the labelling yield was always higher than 95% and the maximum activity of {sup 99m}Tc was about 2220 MBq (60 mCi). The evidences of the efficiency and

Radioimmunodetection of human melanoma tumor xenografts with human monoclonal antibodies

International Nuclear Information System (INIS)

Gomibuchi, Makoto; Saxton, R.E.; Lake, R.R.; Katano, Mitsuo; Irie, R.F.

1986-01-01

A human IgM monoclonal antibody has been established that defines a tumor-associated membrane antigen expressed on human melanoma cells. The antigen has been identified as the ganglioside GD2. In this paper, the authors describe the potential usefulness of the human monoclonal antibody for radioimaging. Nude mice bearing tumors derived from a human melanoma cell line were used as a model. Antibody activity was degradated significantly after labeling with 131 I by the use of a modified chloramine-T method. After testing various concentrations, labeled antibody of a specific activity of 2.8μCi/μg produced the best results. Balb/c nude mice bearing a GD2-positive M14 melanoma cell line were injected with 10-30μg of labeled antibody, and its radiolocalization in different organs and in the whole body were evaluated. The best tumor image was obtained on Day 6. The labeled antibody uptake ratio between tumor and muscle was 9.2:1; the ratio between tumor and liver was 1.4:1. These studies represent the first report of experimental tumor imaging with human monoclonal antibody. Human monoclonals will probably prove to be superior reagents for tumor imaging in melanoma patients if the problem of anti-body radiolysis is resolved. (author)

Recent developments in blood cell labeling research

Energy Technology Data Exchange (ETDEWEB)

Srivastava, S.C.; Straub, R.F.; Meinken, G.E.

1988-09-07

A number of recent developments in research on blood cell labeling techniques are presented. The discussion relates to three specific areas: (1) a new in vitro method for red blood cell labeling with /sup 99m/Tc; (2) a method for labeling leukocytes and platelets with /sup 99m/Tc; and (3) the use of monoclonal antibody technique for platelet labeling. The advantages and the pitfalls of these techniques are examined in the light of available mechanistic information. Problems that remain to be resolved are reviewed. An assessment is made of the progress as well as prospects in blood cell labeling methodology including that using the monoclonal antibody approach. 37 refs., 4 figs.

Recent developments in blood cell labeling research

International Nuclear Information System (INIS)

Srivastava, S.C.; Straub, R.F.; Meinken, G.E.

1988-01-01

A number of recent developments in research on blood cell labeling techniques are presented. The discussion relates to three specific areas: (1) a new in vitro method for red blood cell labeling with /sup 99m/Tc; (2) a method for labeling leukocytes and platelets with /sup 99m/Tc; and (3) the use of monoclonal antibody technique for platelet labeling. The advantages and the pitfalls of these techniques are examined in the light of available mechanistic information. Problems that remain to be resolved are reviewed. An assessment is made of the progress as well as prospects in blood cell labeling methodology including that using the monoclonal antibody approach. 37 refs., 4 figs

Localization of mammary tumors in vivo with 131I-labeled Fab fragments of antibodies against mouse mammary epithelial (MME) antigens

International Nuclear Information System (INIS)

Wilbanks, T.; Peterson, J.A.; Miller, S.; Kaufman, L.; Ortendahl, D.; Ceriani, R.L.

1981-01-01

The Fab fragments of antibodies against cell-type-specific surface antigens of mouse mammary epithelial cells (MME-antigens) were used to localize mammary tumors successfully. The radioiodine-labeled anti-MME (Fab) was injected into mice carrying simulated mammary metastases, and after 24 hours the amount of label per gram of excised tissue was several times greater in the tumor than in liver, brain, lung, or muscle. Kidney showed considerable accumulation of label but this appeared to be nonspecific. Kinetic studies revealed a rapid elimination of labeled Fab in the urine with only 1% of the injected dose remaining in the entire blood pool after 24 hours. Wit a high-purity germanium camera, mammary tumors were clearly located ty the 131 I-labeled anti-MME (Fab), and normalization to /sup 99m/Tc-pertechnetate distribution in the animal increased the specificity. The density of 131 I-label was fourfold greater over the mammary tumor than over comparable areas of the mouse. No accumulation of 131 I-anti-MME (Fab) was observed in nonmammary tumors nor in mammary tumors when labeled nonspecific Fab was used. An analogous system using an antihuman mammary epithelial antiserum is being developed for localization of breast metastases in humans

Safety, Pharmacokinetics, Immunogenicity, and Biodistribution of (186)Re-Labeled Humanized Monoclonal Antibody BIWA 4 (Bivatuzumab( in Patients with Early-Stage Breast Cancer.

NARCIS (Netherlands)

Koppe, M.; Schaijk, F. van; Roos, J.C.; Leeuwen, P.; Heider, K.H.; Kuthan, H.; Bleichrodt, R.P.

2004-01-01

The aim of this prospective study was to evaluate the safety, pharmacokinetics, immunogenicity, and biodistribution of (186)Re-labeled humanized anti-CD44v6 monoclonal antibody (MAb( BIWA 4 (Bivatuzumab( in 9 patients with early-stage breast cancer. Radioimmunoscintigraphy (RIS( was performed within

Preparation of Ga-67 labeled monoclonal antibodies using deferoxamine as a bifunctional chelating agent

International Nuclear Information System (INIS)

Endo, K.; Furukawa, T.; Ohmomo, Y.

1984-01-01

Ga-67 labeled monoclonal IgG or F(ab')/sub 2/ fragments against α-fetoprotein and β-subunit of human choriogonadotropin (HCG), were prepared using Deferoxamine (DFO) as a bifunctional chelating agent. DFO, a well-known iron chelating agent, was conjugated with monoclonal antibodies (Ab) by a glutaraldehyde two step method and the effect of conjugation on the Ab activities was examined by RIA and Scatchard plot analysis. In both monoclonal Ab preparations, the conjugation reaction was favored as the pH increased. However, Ab-binding activities decreased as the molecular ratios of DFO to Ab increased. Preserved Ab activities were observed when Ab contained DFO per Ab molecule less than 2.1. At a ratio of over 3.3 DFO molecules per Ab, the maximal binding capacity rather than the affinity constant decreased. The inter-molecular cross linkage seemed to be responsible for the deactivation of binding activities. The obtained DFO-Ab conjugates, were then easily labeled with high efficiency and reproducibility and Ga-67 DFO-Ab complexes were highly stable both in vitro and in vivo. Thus, biodistribution of Ga-67 labeled F(ab')/sub 2/ fragments of monoclonal Ab to HCG β-subunit was attempted in nude mice transplanted with HCG-producing human teratocarcinoma. Tumor could be visualized, in spite of relatively high background imaging of liver, kidney and spleen. The use of DFO as a bifunctional chelating agent provided good evidence for its applicability to labeling monoclonal Ab with almost full retention of Ab activities. Further, availability of Ga-68 will make Ga-68 DFO-monoclonal Ab a very useful tool for positron tomography imaging of various tumors

Simple, rapid 125I-labeled cyclosporine double antibody/polyethylene glycol radioimmunoassay used in a pediatric cardiac transplant program

International Nuclear Information System (INIS)

Berk, L.S.; Webb, G.; Imperio, N.C.; Nehlsen-Cannarella, S.L.; Eby, W.C.

1986-01-01

We modified the Sandoz cyclosporine radioimmunoassay because of our need for frequent clinical monitoring of cyclosporine drug levels in allo- and xenograft pediatric cardiac transplant patients. With application of a commercially available [ 125 I]cyclosporine label in place of [ 3 H]cyclosporine and a second antibody/polyethylene glycol (PEG) method of separation in place of charcoal separation, we simplified and enhanced the speed and precision of assay performance. Studies of 140 whole blood samples comparing this new method to the [ 3 H]cyclosporine radioimmunoassay (RIA) method of Berk and colleagues yielded a coefficient of correlation of 0.96 (p less than 0.00001) with means of 626 and 667 ng/ml for [ 3 H]RIA and [ 125 I]RIA, respectively, and a regression equation of y = 28 + 1.02x. The major advantages are that total assay time is reduced to approximately 1 h; [ 125 I]cyclosporine label is used, avoiding the problems associated with liquid scintillation counting; and precision is enhanced by separating bound and free fractions with second antibody/PEG. These modifications should provide for greater ease of assay performance and improved clinical utility of cyclosporine monitoring not only in the pediatric but also in the adult transplant patient

Diagnosis of colorectal carcinomas and recurrence with 99m Tc labeled monoclonal anti-CEA-antibody (BW 431/26)

International Nuclear Information System (INIS)

Lind, P.; Langsteger, W.; Koeltringer, P.; Eber, O.; Beham, A.

1989-01-01

With the introduction of 99m Tc labeled monoclonal antibodies against CEA, a clinically relevant extension can be expected in the diagnosis of colorectal tumors by immunoscintigraphy (IS). This study comprises a total of 31 patients (primary tumors, occult neoplasms with elevated CEA serum level, suspicious recurrences). In primary tumors (n = 14), all coloscopically diagnosed carcinomas were confirmed and correctly localised by IS (n = 8). In 4 cases IS was true negative, in one case false positive; in one patient a stomach adenocarcinoma could be demonstrated. In the diagnosis of recurrences (n = 17) IS revealed an uptake in TCT (transmission computed tomography) and coloscopically suspicious areas in 10 cases. In 6 cases IS was negative (5 true negative findings in scar or granulation tissue, 1 false negative finding in paraaortal lymphnodes). In one patient the raised CEA level was due to multiple liver metastases, a local recurrence could not be detected. Elevated serum CEA-levels were found only in 10 of 19 patients with true positive IS. In postoperative cancer care IS with 99m Tc-labeled anti-CEA antibody (MAK BW 431/26) plays a preeminent role in the exclusion or diagnosis of kolorectal recurrences in case of ambiguous TCT or endoscopic findings. (Author)

Ior-CEA-1: Labelling, quality control and clinical evaluation

International Nuclear Information System (INIS)

Pimentel, G.J.

1998-01-01

Within the Co-ordinated Programme on Labelling, Quality Control and Evaluation of Monoclonal Antibodies, the IAEA has made a great effort to expand efficient labelling methods, mainly those with radioisotopes which have been used for radioimmunoscintigraphy. In this sense, more recently 99 Tc m has been mostly employed in the majority of the investigations due to its ideal physical characteristics. Efficient labelling of monoclonal antibodies depends on a number of factors including the method and way of the label incorporation into the protein. During the last years several direct labelling approaches have been developed, which led to attain simple and inexpensive methods for medical practice, as well as safe and stable techniques which bring accurate and good quality images. Accordingly, this paper describes the results obtained during last five years which come from the comparison among different labelling systems, passing through the quality control to test the labelled monoclonal stability and the protein bioreactivity, to continue in the clinical evaluation of ior-CEA-1, as well as the evaluation of other antibodies. Up to now we have evaluated more than 70 patients with the anti-CEA monoclonal antibody (ior-CEA-1), examined in different clinical assays such as: pilot, phase I-II and extensive phase III-IV trials, whose results are encouraging. It confirms that the employed labelling approach was safe and adequate

Selection of well labelled insulin fractions for radioimmunoassay use

Energy Technology Data Exchange (ETDEWEB)

Awh, O D; Kim, J R [Korea Atomic Energy Research Inst., Seoul (Republic of Korea)

1980-06-01

Selection methods of well labelled insulin fractions based on two different criteria were compared to establish an efficient low level RIA of insulin and to elucidate the correlation between the immunoreactivity and the charcoal-adsorptivity of the radioiodine labelled insulin. The result indicated that the selection of well labelled insulin fractions by means of a charcoal-adsorption test is inappropriate. Generally, the distribution of radioactivity, antibody-bindability, and charcoal-adsorptivity of the labelled insulin was not consistent with each other. Thus, the selection should be carried out for every labelling batch to get the utmost assay reliability by antibody-bindability but not by charcoal-adsorptivity. By using the well selected labelled insulin fractions based on antibody-binding, a correct assay for a reference serum was possible, and by extending the incubation time up to 96 hrs, a sharp dose response curve could be obtained even in the range of below 5 ..mu..U/ml standard insulin doses.

New aspects of radioimmunochemical measurement of human parathyroid hormone using the labelled antibody technique

International Nuclear Information System (INIS)

Hesch, R.D.; McIntosh, C.H.S.; Woodhead, J.S.; Welsh National School of Medicine, Cardiff

1975-01-01

Two forms of heterogeneity of parathyroid hormone (PTH) have given rise to conflicting results: one due to the heterogeneity of the secreted species from the gland and their peripheral metabolism and the other representing the immunochemical heterogeneity of the available antibodies. We have developed sequence specific assays using the technique of labelled antibodies. Therefore, results of assays measuring the C-terminal part and the (1-34)-N-terminal part of the molecule could be compared to those of an assay for hormone bearing both N- and C-terminal antigenic determinants. This assay is supposed to detect predominantly (1-84)-intact hormone. The immunoradiometric assay of (1-34)-PTH has a sensitivity of 0.04 ng/ml. This technique avoids the critical iodination of the hormone fragment containing no tyrosine. There is the expected overlap between normal subjects and patients with primary and secondary hyperparathyroidism. The most important finding are results from patients undergoing neck catheterization. We demonstrated nonuniform secretion of different species of PTH by parathyroid adenomata and normal glands. This supports the hypothesis of cleavage of the (1-84)-molecule in the gland. (orig.) [de

A dual amplified electrochemical immunosensor for ofloxacin: Polypyrrole film-Au nanocluster as the matrix and multi-enzyme-antibody functionalized gold nanorod as the label

International Nuclear Information System (INIS)

Zang, Shuai; Liu, Yingju; Lin, Mouhong; Kang, Jianli; Sun, Yuanming; Lei, Hongtao

2013-01-01

Graphical abstract: Schematic representation of the OFL electrochemical immunosensor using Au nanoclusters/PPy/GCE as the substrate and multi-HRP-GNR-Ab2 bioconjugates as the label. Highlights: ► Gold nanorod was used to load HRP and Ab 2 to form multi-HRP-GNR-Ab 2 . ► A sensitive immunosensor for ofloxacin was constructed using the homemade antibody. ► A dual signal amplified strategy was based on the PPy-Au and multi-HRP-GNR-Ab 2 . -- Abstract: In this work, an electrochemical immunosensor, basing on a dual signal amplified strategy by employing a biocompatible polypyrrole film-Au nanocluster matrix as a sensor platform and multi-enzyme-antibody functionalized gold nanorod as an electrochemical detection label, is established for sensitive detection of ofloxacin (OFL). Firstly, polypyrrole film and Au nanoclusters were progressively fabricated onto the surface of a glassy carbon electrode via electropolymerization and electrochemical deposition, respectively. Such PPy-Au nanocomposite modified electrode was used to immobilize OFL-OVA, blocked with the blocking reagent, and then associated with the corresponding antibody. Secondly, gold nanorod (GNR) was synthesized to load horseradish peroxidase (HRP) and horseradish peroxidase-secondary antibody (HRP-Ab 2 ), and the resulting nanostructure (multi-HRP-GNR-Ab 2 ) was applied as the detection label. The fabrication process of the ordered multilayer structure and immunosensor were characterized by scanning electron microscopy (SEM) and electrochemical measurements, respectively. Finally, based on a competitive immunoassay, i.e., the association ability with the corresponding antibody between the captured antigen and free OFL in the solution, the fabricated immunosensor exhibited a sensitive response to OFL in the range from 0.08 to 410 ng/mL with a detection limit of 0.03 ng/mL. The current immunosensor exhibited good sensitivity, selectivity and long-term stability. This amplification strategy shows excellent

Development of radiolabelling techniques of anti-CEA monoclonal antibody

International Nuclear Information System (INIS)

Castiglia, S.G. de

1998-01-01

The purpose of this work was to label monoclonal and polyclonal antibodies with 99 Tc m such as the ior-CEA-1 antibody and polyclonal IgG using a direct method, to check the radiochemical and biological behavior of labelled products, to prepare it under sterile and apyrogenic conditions as a lyophilized kit and to employ it in clinical trials. In addition, a photoactivation method was used to label polyclonal IgG with 99 Tc m and to compare with the established method using mercaptoethanol (2-ME) as the reducing agent. Finally polyclonal IgG was labelled using an indirect method in which a chelator was covalently attached to the protein and the 99 Tc m added as glucoheptonate complex. The properties of 99 Tc m when labelled with monoclonal and polyclonal antibodies by different methods were assessed by in vitro and in vivo studies

Does heterogeneity of pimonidazole labelling correspond to the heterogeneity of radiation-response of FaDu human squamous cell carcinoma?

International Nuclear Information System (INIS)

Yaromina, Ala; Hoelscher, Tobias; Eicheler, Wolfgang; Rosner, Andrea; Krause, Mechthild; Hessel, Franziska; Petersen, Cordula; Thames, Howard D.; Baumann, Michael; Zips, Daniel

2005-01-01

Background and purpose: Pimonidazole is a marker for hypoxic cells which are radioresistant and thereby important for the outcome of radiotherapy. The present study evaluates heterogeneity in pimonidazole binding within and between tumours and relates the results to the heterogeneity of radiation response in the same tumour cell line. Materials and methods: FaDu, a poorly differentiated human squamous cell carcinoma line, was transplanted subcutaneously into the right hind-leg of NMRI nude mice. Tumours were irradiated with graded single doses either under ambient or clamped blood flow conditions and local tumour control was evaluated after 120 days. Complete dose-response curves for local tumour control were generated and the slope, a measure of heterogeneity of radiation response, was determined. In parallel, 12 unirradiated tumours were examined histologically. Seven serial 10 μm cross-sections per tumour were evaluated using fluorescence microscopy and computerised image analysis to determine the pimonidazole hypoxic fraction (pHF). Heterogeneity in pHF was quantified by its coefficient of variation (CV). Poisson-based model calculations considering the intertumoural heterogeneity of pHF were performed and the slopes of the predicted and the observed dose-response curves were compared. Results: The mean pHF was 11% [CV 50%] when one central section per tumour was evaluated. Measurements of multiple sections per tumour resulted in a mean pHF of 12% [CV 46%] (P=0.7). Intertumoural heterogeneity in pHF was more pronounced than heterogeneity in individual tumours by a factor of 2. Model calculations based on the variability in pHF resulted in similar slopes of the dose-response curve for local tumour control in comparison with the observed slope when the heterogeneity in an unknown and arbitrarily chosen additional radiobiologically relevant parameter, in this example clonogen density, was taken into account. Conclusions: While the average pimonidazole hypoxic

Monoclonal Antibodies Radiolabeling with Rhenium-188 for Radioimmunotherapy

Science.gov (United States)

Martini, Petra; Pasquali, Micol

2017-01-01

Rhenium-188, obtained from an alumina-based tungsten-188/rhenium-188 generator, is actually considered a useful candidate for labeling biomolecules such as antibodies, antibody fragments, peptides, and DNAs for radiotherapy. There is a widespread interest in the availability of labeling procedures that allow obtaining 188Re-labeled radiopharmaceuticals for various therapeutic applications, in particular for the rhenium attachment to tumor-specific monoclonal antibodies (Mo)Abs for immunotherapy. Different approaches have been developed in order to obtain 188Re-radioimmunoconjugates in high radiochemical purity starting from the generator eluted [188Re]ReO4−. The aim of this paper is to provide a short overview on 188Re-labeled (Mo)Abs, focusing in particular on the radiolabeling methods, quality control of radioimmunoconjugates, and their in vitro stability for radioimmunotherapy (RIT), with particular reference to the most important contributions published in literature in this topic. PMID:28951872

Current status of radioligand antibodies in the treatment of malignancy

International Nuclear Information System (INIS)

Maners, A.W.; Sanders, M.M.; Pappas, A.A.

1988-01-01

Monoclonal anti-tumor antibodies labeled with a radioactive moiety present an exciting new approach to cancer therapy. With the advent of hybridoma technology, monoclonal antibodies can now be produced in quantity. Indeed, antibodies against tumor-related and tumor-specific antigens have been produced, labeled with a radioactive substance, and used therapeutically. The rationale for this therapeutic approach and the results of human clinical trials will be reported herein.27 references

Dynamic interaction of 111indium-labeled monoclonal antibodies with surface antigens of solid tumors visualized in vivo by external scintigraphy

International Nuclear Information System (INIS)

Hwang, K.M.; Keenan, A.M.; Frincke, J.; David, G.; Pearson, J.; Oldham, R.K.; Morgan, A.C. Jr.

1986-01-01

Two 111 indium-labeled murine monoclonal antibodies (MoAb), D3 and 9.2.27, directed to tumor antigens of L-10 hepatocarcinoma and human melanoma, respectively, selectively localized antigen-positive target cells in guinea pigs and nude mice. The fate of MoAb differed in the two antigen-antibody systems after reacting with their corresponding tumor antigens in vivo as reflected by patterns of distribution and turnover in vivo. The 9.2.27 localized in melanoma xenograft in nude mice after intravenous administration with slow loss from tumor but more rapid loss from normal tissues and thus demonstrated optimal imaging of small tumors (approximately equal to 5 mm) between 3 and 6 days after injection of the radiolabeled antibody. In contrast, D3 demonstrated a biphasic localization in guinea pig L-10 hepatocarcinoma with a maximal activity on the 2d day after administration and showed rapid loss from both tumor and normal tissues. Nonspecific localization of antibodies in liver and in kidney was found both in syngeneic (nude mice) and xenogeneic (guinea pig) hosts but was more pronounced in the xenogeneic species. These results indicate that the nature of the antigen-antibody interaction may be of importance in selecting MoAb for both diagnosis and therapy of malignant diseases

Current state of the art of blood cell labeling

International Nuclear Information System (INIS)

Srivastava, S.C.; Straub, R.F.; Meinken, G.E.; Gil, M.C.

1985-01-01

An update on some recent developments in the area of blood cell labeling is provided. Specific topics covered include red cell labeling with /sup 99m/Tc, platelet labeling using an antiplatelet monoclonal antibody, and the labeling of leukocytes with /sup 99m/Tc. Mechanistic information, where available, is discussed. A critical evaluation of current techniques, their pitfalls as well as advantages, and the problems that remain to be resolved, is presented. The promise shown by recent results using the antibody approach for cell labeling is emphasized. An assessment of the progress made in these areas is presented. 38 refs., 10 figs., 6 tabs

Radioimmunoassay with heterologous antibody (hetero-antibody RIA)

International Nuclear Information System (INIS)

Iwasawa, Atsushi; Hayashi, Hiroaki; Itoh, Zen; Wakabayashi, Katsumi

1991-01-01

To develop a homologous radioimmunoassay (RIA) for a hormone of a small or rare animal often meets difficulty in collecting a large amount of purified antigen required for antibody production. On the other hand, to employ a heterologous RIA to estimate the hormone often gives poor sensitivity. To overcome this difficulty, a 'hetero-antibody' RIA was studied. In a hetero-antibody RIA system, a purified preparation of a hormone is used for radioiodination and standardization and a heterologous antibody to the hormone is used for the first antibody. Canine motilin and rat LH were selected as examples, and anti-porcine motilin and anti-hCG, anti-hCGβ or anti-ovine LHβ was used as the heterologous antibody. The sensitivities of the hetero-antibody RIAs were much higher than those of heterologous RIAs in any case, showing that these hetero-antibody RIA systems were suitable for practical use. To clarify the principle of hetero-antibody RIA, antiserum to porcine motilin was fractionated on an affinity column where canine motilin was immobilized. The fraction bound had greater constants of affinity with both porcine and canine motilins than the rest of the antibody fractions. This fraction also reacted with a synthetic peptide corresponding to the C-terminal sequence common to porcine and canine motilins in a competitive binding test with labeled canine motilin. These results suggest that an antibody population having high affinity and cross-reactivity is present in polyclonal antiserum and indicate that the population can be used in hetero-antibody RIA at an appropriate concentration. (author)

Radiolabeled monoclonal antibodies for imaging and therapy: Potential, problems, and prospects: Scientific highlights

International Nuclear Information System (INIS)

Srivastava, S.C.; Buraggi, G.L.

1986-01-01

This meeting focused on areas of research on radiolabeled monoclonal antibodies. Topics covered included the production, purification, and fragmentation of monoclonal antibodies and immunochemistry of hybridomas; the production and the chemistry of radionuclides; the radiohalogenation and radiometal labeling techniques; the in-vivo pharmacokinetics of radiolabeled antibodies; the considerations of immunoreactivity of radiolabeled preparations; the instrumentation and imaging techniques as applied to radioimmunodetection; the radiation dosimetry in diagnostic and therapeutic use of labeled antibodies; the radioimmunoscintigraphy and radioimmunotherapy studies; and perspectives and directions for future research. Tutorial as well as scientific lectures describing the latest research data on the above topics were presented. Three workshop panels were convened on ''Methods for Determining Immunoreactivity of Radiolabeled Monoclonal Antibodies - Problems and Pitfalls,'' Radiobiological and Dosimetric Considerations for Immunotherapy with Labeled Antibodies,'' and ''The Human Anti-Mouse Antibody Response in Patients.''

Vascular graft infection: Detection by 123I-labeled antigranulocyte antibody (anti-NCA95) scintigraphy

International Nuclear Information System (INIS)

Cordes, M.; Hepp, W.; Langer, R.; Pannhorst, J.; Hierholzer, J.; Felix, R.; Universitaetsklinikum Rudolf Virchow, Berlin

1991-01-01

A total of 40 scintigraphic examinations were performed after vascular reconstructive surgery in 27 patients in whom there was a clinical suspicion of vascular graft infection. Whole-body gamma camera images were obtained at 4 and 24 h after i.v. administration of 111 MBq 123 I-labeled antigranulocyte antibody Anti-NCA95. Scan results were interpreted without clincal information and were subsequently correlated with computed tomography. Prosthetic vascular graft infection was confirmed in 9 patients and excluded in 18 by surgical findings, bacteriology and/or clinical course. Scintigraphy revealed true-positive results in 16 of 40 and false-negative results in 1 of 40 examinations. True-negative results were found in 19 and 16, false-positive results in 4 and 7 examinations at 4 and 24 h p.i., resp. The sensitivity was calculated to be 94% for both early (4 h) and late (24 h) images whereas the specificity ws 83% and 70%, resp. In all cases the application of the murine antibody was safe and no side effects or complications were noted. Limitations of this diagnostic procedure are accumulations of granulocytes in hematomas which may be observed in the non-complicated early course following reconstructive surgery. (orig.) [de

Evaluation of radioiodinated and radiocopper labeled monovalent fragments of monoclonal antibody chCE7 for targeting of neuroblastoma

International Nuclear Information System (INIS)

Carrel, Francois; Amstutz, Hanspeter; Novak-Hofer, Ilse; Schubiger, P. August

1997-01-01

Monovalent fragments of antineuroblastoma antibody mAb chCE7 were evaluated for their in vitro and in vivo tumor cell binding properties. Single chain fragments were constructed from the variable region genes cloned from hybridoma cells, expressed in E.coli and purified by metal chelate affinity chromatography. Radioiodinated CE7-scFv fragments were found to bind with high affinity (K d ∼10 -9 M) to target cells in vitro but formed aggregates at 37 deg. C, and bound to serum proteins in vitro and in vivo. Circular Dichroism spectra revealed the protein to be in a conformationally altered form and no permanent 'refolding' could be achieved. In contrast, chCE7-Fab fragments were found to bind to target tumor cells with similar affinity than the parent mAb chCE7 (K d ∼10 -10 M), showed no tendency to aggregate and were stable in serum both in vitro and in vivo. Kinetics of association and dissociation of radioiodinated scFv and Fab fragments were found to be rapid. Radioiodination with the Iodogen method led to impaired immunoreactivity which was found to further increase the off- rates of radioiodinated fragments from tumor cells. Radioiodination with the Bolton-Hunter reagent as well as labeling of chCE7-Fab fragments with 67 Cu via the macrocyclic CPTA ligand led to fully immunoreactive Fab fragments. Radioiodinated and radiocopper labeled monovalent CE7 fragments did not internalize into target tumor cells as the parent mAb and its F(ab') 2 fragment. A comparison of the biodistribution in tumor bearing nude mice of the radiocopper labeled monovalent, non internalizing Fab fragments with the internalizing divalent F(ab') 2 fragments showed in both cases high levels of radioactivity in the kidneys. Concerning tumor uptake, radioactivity from both internalizing and non internalizing fragments remained associated with tumor tissue for longer times than in case of the corresponding radioiodinated fragments. When compared with the radioiodinated forms, tumor uptake

Photonic crystal fiber based antibody detection

DEFF Research Database (Denmark)

Duval, A; Lhoutellier, M; Jensen, J B

2004-01-01

An original approach for detecting labeled antibodies based on strong penetration photonic crystal fibers is introduced. The target antibody is immobilized inside the air-holes of a photonic crystal fiber and the detection is realized by the means of evanescent-wave fluorescence spectroscopy...

[VGKC-complex antibodies].

Science.gov (United States)

Watanabe, Osamu

2013-04-01

Various antibodies are associated with voltage-gated potassium channels (VGKCs). Representative antibodies to VGKCs were first identified by radioimmunoassays using radioisotope-labeled alpha-dendrotoxin-VGKCs solubilized from rabbit brain. These antibodies were detected only in a proportion of patients with acquired neuromyotonia (Isaacs' syndrome). VGKC antibodies were also detected in patients with Morvan's syndrome and in those with a form of autoimmune limbic encephalitis. Recent studies indicated that the "VGKC" antibodies are mainly directed toward associated proteins (for example LGI-1 and CASPR-2) that complex with the VGKCs themselves. The "VGKC" antibodies are now commonly known as VGKC-complex antibodies. In general, LGI-1 antibodies are most commonly detected in patients with limbic encephalitis with syndrome of inappropriate secretion of antidiuretic hormone. CASPR-2 antibodies are present in the majority of patients with Morvan's syndrome. These patients develop combinations of CNS symptoms, autonomic dysfunction, and peripheral nerve hyperexcitability. Furthermore, VGKC-complex antibodies are tightly associated with chronic idiopathic pain. Hyperexcitability of nociceptive pathways has also been implicated. These antibodies may be detected in sera of some patients with neurodegenerative diseases (for example, amyotrophic lateral sclerosis and Creutzfeldt-Jakob disease).

Biodistribution, pharmacokinetic, and imaging studies with 186Re-labeled NR-LU-10 whole antibody in LS174T colonic tumor-bearing mice

International Nuclear Information System (INIS)

Goldrosen, M.H.; Biddle, W.C.; Pancook, J.; Bakshi, S.; Vanderheyden, J.L.; Fritzberg, A.R.; Morgan, A.C. Jr.; Foon, K.A.

1990-01-01

Biodistribution, pharmacokinetic, and radioimaging studies were performed with 186Re-labeled NR-LU-10 whole antibody in athymic nude mice bearing the LS174T tumor growing either s.c. or in an experimental hepatic metastasis model. NR-LU-10 is an IgG2b murine monoclonal antibody (MAb) that reacts with virtually all human tumors of epithelial origin. NR-BC-1, a IgG2b murine MAb that reacts with normal human B-cell and B malignancies, was used as an isotype-matched control. These MAbs were radiolabeled with 186Re by a preformed chelate approach by using the triamide thiolate ligand system. 186Re-labeled NR-LU-10 (50 microCi) was injected into nude mice bearing LS174T tumors growing s.c. Biodistribution studies revealed that the LS174T tumor retained the highest concentration of 186Re-labeled NR-LU-10 at day 6. The tumor:blood ratio ranged from 0.1:1 to 10.8:1 by day 6, the last day of analysis. In contrast the tumor:blood ratio of 186Re-labeled NR-BC-1, the isotype-matched MAb control, was 1:1 on day 6. Pharmacokinetic analysis indicated that the t1/2 beta of NR-LU-10 for blood and other tissues ranged from 21 to 25 h, while the t1/2 beta for the LS174T tumor averaged 52 h. The area under the curve for tumor compared to blood was 2.8- to 5.7-fold higher than the area under the curve for all other tissues and organs. The mean residence time for NR-LU-10 in blood and all other organs ranged from 23 to 26 h, while the mean residence time for NR-LU-10 in the LS174T tumor was 72 h. Scintigraphic images revealed selective uptake of the 186Re-labeled NR-LU-10, but not of the 186Re-labeled NR-BC-1, at the LS174T tumor site. Studies in an experimental model of hepatic metastasis revealed a similar selective pattern of 186Re-labeled NR-LU-10 accumulation. Scintigraphic images of the LS174T tumor growing within the athymic nude mouse liver were obtained

Bone marrow dosimetry for monoclonal antibody therapy

International Nuclear Information System (INIS)

Bigler, R.E.; Zanzonico, P.B.; Leonard, R.

1986-01-01

Immunoglobulins must permeate through the basement membrane of capillaries in order to enter the extracellular space (ECS) of tissue. Since the process is quite slow, the blood plasma activity in various organs contributes considerably to the radiation dose of the dose-limiting tissues. In bone marrow the basement membrane is absent and the blood circulation is functionally open. Therefore, blood plasma and marrow ECS maintain equal concentrations of labeled immunoglobulins. A combination of factors including intravenous administration, slow absorption into most tissues, slow breakdown and elimination of labeled immunoglobulin, and rapid entry into bone marrow ECS as well as known radiosensitivity of marrow led the authors to expect this tissue would prove to be the primary tissue at risk for systemic monoclonal antibody therapy. They have developed and applied in a Phase I clinical study of 131 I labeled CEA antibody a procedure for estimation of radiation dose to red bone marrow. Serieal measurements of blood plasma and total body retention are carried out. Binding of labeled antibody to the cellular components of blood is verified to be very low. They have observed bone marrow depression at doses greater than 400 rad. If no special procedures are used to reconstitute marrow after radiation treatment, this level represents a much greater than generally recognized limitation to radiolabeled monoclonal antibody therapy. 25 references, 4 tables

Monoclonal antibody

International Nuclear Information System (INIS)

Oyamada, Hiyoshimaru

1987-01-01

Some aspects of monoclonal antibodies are described, centering on studies made by the author and those presented at the Second International Conference on Monoclonal Antibody Immunoconjugates for Cancer held in March this year (1987). The history of immuno-nuclear medicine and procedures for producing monoclonal antibodies are briefly outlined. Monoclonal antibodies are immunoglobulins. Here, the structure of IgG, which is used most frequently, is described. An IgG is composed of two antigen binding fragments (Fab) and one crystallizable fragment (Fc). The end portion of a Fab reacts with an antigen. One of the major applications of immuno-nuclear medicine is the diagnosis of cancer. As label nucleides, 131 I and 111 I were selected in most cases in the past while 123 I and 99m Tc are currently used more often. Advantages and disadvantages of this diagnosis method is discussed citing studies presented at the First (1986) and Second (1987) International Conference on Monoclonal Antibody Immunoconjugates for Cancer. The present status of the application of monoclonal antibodies to treatment of cancer is also described. (Nogami, K.)

Radioiodine-labelled compounds previously or currently used for tumour localization

International Nuclear Information System (INIS)

Beierwaltes, W.H.

1976-01-01

131 I-labelled human serum albumin, though not used for tumour localization today, is an excellent ''standard'' with which to compare uptake of ''tumour-specific'' radiolabelled compounds. 131 I-labelled fibrinogen and antibodies to fibrinogen have a non-specific uptake in tumours. Nungester, Beierwaltes and Knorpp are credited by Mahaley as first treating a human for cancer with 131 I-labelled antibody globulins (malignant melanoma). Although many theoretical problems remain in obtaining diagnostic localization of 131 I-IgG, Quinones, Mizejewski and Beierwaltes demonstrated the uptake of 131 I-labelled immune antibodies in Syrian hamster cheeck pouch with chorionic gonadotropic hormone as the specific tumour-associated antigen. This model was then used successfully by Goldenberg and Hoffer for demonstrating colon carcinoma by using antibodies to carcinoembryonic antigen. A 131 I-labelled chloroquine analogue, synthesized by Counsell, has been demonstrated by Beierwaltes et al. to concentrate diagnostically and therapeutically in the malignant melanotic melanoma. 131 I-19-iodocholesterol, synthesized by Counsell, has been demonstrated by Beierwaltes et al. to concentrate diagnostically in the human adrenal cortex. It has many unique diagnostic capabilities not available with other routine diagnostic methods available today. (author)

Comparative studies of 111In-labeled monoclonal antibody using spacer-containing and non-spacer bifunctional chelates. 2

International Nuclear Information System (INIS)

Sun, Baofu

1994-01-01

Indium-111-labeled A7 monoclonal antibodies using two spacer-containing chelates, succinimido-EGS-DTPA (EGS-DTPA: diester spacer) and maleimido-C10-Bz-EDTA (C10-Bz-EDTA: hydrocarbon spacer) were investigated in human LS180 colon tumor bearing nude mice and were compared with two non-spacer chelates, cyclic DTPA dianhydride (cDTPAA) and isothiocyanatobenzyl-EDTA (SCN-Bz-EDTA). Compared with immunoconjugates using non-spacer chelates, immunoconjugates using spacer-containing chelates, especially C10-Bz-EDTA-A7 showed lower 111 In activity in normal organs. The radioactivity in the liver for C10-Bz-EDTA-A7 decreased continuously till 96 hrs postinjection, however, this liver radioactivity for EGS-DTPA-A7 showed little change after 24 hrs. Moreover, in liver subcellular distribution study, EGS-DTPA-A7 showed a higher activity retention in mitochondrial fraction which contained lysosome, a place for metabolizing and storing of 111 In labeled antibody, than that of C10-Bz-EDTA-A7. The C10-Bz-EDTA-A7 conjugate demonstrated more preferable tumor-to-non tumor contrast on the scintigrams than that found with other three immunoconjugates. Up to 96 hrs postinjection, tumor bearing nude mice injecting with immunoconjugates using spacer-containing chelates exreted twice radioactivity from whole body than that excreted by using non-spacer chelates. Interestingly, different from other three chelates, C10-Bz-EDTA-A7 were mainly excreted via feces. We conclude that the decrease of radioactivity in normal tissues in the case of EGS-DTPA-A7 was due to the rapid decrease of activity in the blood, while in the case of C10-Bz-EDTA-A7 it was due to the quickly excreted small metabolite through faces. 111 In labeled C10-Bz-EDTA conjugate is superior, at least when conjugated with A7, to other three chelate conjugates used in this study. (author)

In vivo imaging and quantitation of renal transplant rejection using indium-111 labelled anti-lymphocyte and anti-MHC class I and II monoclonal antibodies in a rat model

International Nuclear Information System (INIS)

Loutfi, I.; Batchelor, J.R.; Lavender, J.P.

1992-01-01

It has been described in this report, non-invasive and specific method for imaging and assessment of acute kidney transplant rejection in rat model. This model can serve as a basis for application in man using a cocktail of monoclonal antibodies with different specificities starting with monoclonal antibodies labelled with indium-111 which have been used in this technique. 3 refs., 1 tab., 2 figs

Research co-ordination meeting on labelling, quality control and clinical evaluation of monoclonal antibodies for scintigraphy, Kuala Lumpur, Malaysia, 9-13 September 1991

International Nuclear Information System (INIS)

1991-09-01

The Co-ordinated Research Programme (CRP) on ''Labelling, quality control and clinical evaluation of monoclonal antibodies for scintigraphy'' arose from the deliberations at an IAEA Consultants' Meeting (CM) on ''Radiolabelling techniques of monoclonal antibodies'' held in Vienna on 22-24 August 1988. The following is a brief description of the relevant recommendations arising from said meeting. A more detailed description of the proceedings may be found in the summary report issued on 8 December 1989. This report incorporates the results of the first Research Co-ordination Meeting (RCM) of subject CRP held in Kuala Lumpur, Malaysia on 9-13 September 1991. 9 refs

Preparation of monoclonal antibodies against cardiac myosin and some radiolabelling studies

International Nuclear Information System (INIS)

Bapat, K.; Venkatesh, M.; Pillai, M.R.A.; Sarma, H.D.; Sainis, K.B.

1998-01-01

Monoclonal antibodies were raised against myosin, a specific indicator of myocardial infarction and labelled with 125 I and 99m Tc. Human cardiac myosin was isolated from normal human heart and was used for raising the monoclonal antibodies by the hybridoma technique. Antibody producing clones were identified by ELISA and cloning was done by the limiting dilution technique. Of the 13 clones obtained, 4 were deemed suitable for further studies. The antibodies were grown in ascites, purified, isotyped and their cross reactions with other forms of myosin were estimated. All the clones showed negligible cross reaction with rabbit myosin, but reacted to different extents with bovine skeletal myosin. The most avid antibody Mab-4G4 was chosen for further labelling studies. Mab-4G4 was labelled with 125 I using different oxidising agents such as iodogen, chloramine-T and lactoperoxidase. Purified radioiodinated antibody with radiochemical purity >95% could be obtained by gel filtration. Immunoreactivity was retained as tested by binding to myosin immobilised on a solid support. Mab-4G4 was also labelled with 99m Tc using stannous tartrate as the reducing agent. Radiolabelling yield was ∼60%, the purity was >95% and the immunoreactivity was retained. Both the labelled preparations were tested for bio-distribution in normal and infarcted rats. The activity accumulation in the infarcted region was ∼ 1.5 and 3.5 times as that in normal heart muscle for 125 I and 99m Tc labelled Mab-4G4 respectively. The major problem with the iodinated antibody was the in vivo deiodination resulting in very high percentage of activity in the thyroid. Although the fraction of the total activity associated with the infarcted heart is not very impressive, the fact that the activities with the infarcted and normal hearths are significantly different is heartening. With further optimisation of labelling and use of F(ab)'2 fragments, better delineation of the infarct sites is aspired. (author)

Beneficial effect of antibodies against β- secretase cleavage site of APP on Alzheimer's-like pathology in triple-transgenic mice.

Directory of Open Access Journals (Sweden)

Inna Rabinovich-Nikitin

Full Text Available The toxicity of amyloid β and tau, the two hallmark proteins in Alzheimer's disease (AD, has been extensively studied individually. Recently new data suggest their possible interactions and synergistic effects in the disease. In this study, we investigate the ability of antibodies against the β secretase cleavage site on APP, named BBS1, to affect tau pathology, besides their well established effect on intracellular Aβ and amyloid load. For this purpose we treated the triple transgenic mice model of AD (3x Tg-AD with mAb BBS1 intracerebroventricularly, using mini osmotic pumps for one month. The experimental data demonstrated reduction in total and phosphorylated tau levels, explained by significant reduction in GSK3β which phosphorylates tau on sites recognized by antibodies against PHF1 and AT-8. The treatment increased the cognitive capabilities and reduced the brain inflammation levels which accompany AD pathology. The data showing that tau pathology was significantly reduced by BBS1 antibodies suggest a close interaction between tau and Aβ in the development of AD, and may serve as an efficient novel immunotherapy against both hallmarks of this disease.

Detection of D2-40 monoclonal antibody-labeled lymphatic vessel invasion in esophageal squamous cell carcinoma and its clinicopathologic significance

International Nuclear Information System (INIS)

Bai, Bing; Ma, Wei; Wang, Kai; Ha, Sita; Wang, Jian-Bo; Tan, Bing-Xu; Wang, Na-Na; Yang, Sheng-Si; Jia, Yi-Bin; Cheng, Yu-Feng

2013-01-01

This study aims to investigate the clinicopathologic significance of lymphatic vessel invasion (LVI) labeled by D2-40 monoclonal antibody in esophageal squamous cell carcinoma (ESCC). Immunohistochemical assay was used to detect the expression of D2-40 and LVI in 107 ESCC patients. Then, the correlation between the clinicopathologic feature and the overall survival time of the patients was analyzed. The lymph node metastasis rates were 70% and 21% in the LVI-positive and LVI-negative groups, respectively. The nodal metastasis rate was higher in the LVI-positive group than in the LVI-negative group. Multivariate regression analysis showed that LVI was related to nodal metastasis (P<0.001). The median survival time of the patients was 26 and 43 months in the LVI-positive and LVI-negative groups, respectively. Although univariate regression analysis showed significant difference between the two groups (P=0.014), multivariate regression analysis revealed that LVI was not an independent prognostic factor for overall survival in the ESCC patients (P=0.062). Lymphatic node metastasis (P=0.031), clinical stage (P=0.019), and residual tumor (P=0.026) were the independent prognostic factors. LVI labeled by D2-40 monoclonal antibody is a risk factor predictive of lymph node metastasis in ESCC patients

Imaging small human prostate cancer xenografts after pretargeting with bispecific bombesin-antibody complexes and targeting with high specific radioactivity labeled polymer-drug conjugates

International Nuclear Information System (INIS)

Patil, Vishwesh; Gada, Keyur; Panwar, Rajiv; Ferris, Craig; Khaw, Ban-An; Varvarigou, Alexandra; Majewski, Stan; Weisenberger, Andrew; Tekabe, Yared

2012-01-01

Pretargeting with bispecific monoclonal antibodies (bsMAb) for tumor imaging was developed to enhance target to background activity ratios. Visualization of tumors was achieved by the delivery of mono- and divalent radiolabeled haptens. To improve the ability to image tumors with bsMAb, we have combined the pretargeting approach with targeting of high specific activity radiotracer labeled negatively charged polymers. The tumor antigen-specific antibody was replaced with bombesin (Bom), a ligand that binds specifically to the growth receptors that are overexpressed by many tumors including prostate cancer. Bom-anti-diethylenetriaminepentaacetic acid (DTPA) bispecific antibody complexes were used to demonstrate pretargeting and imaging of very small human prostate cancer xenografts targeted with high specific activity 111 In- or 99m Tc-labeled negatively charged polymers. Bispecific antibody complexes consisting of intact anti-DTPA antibody or Fab' linked to Bom via thioether bonds (Bom-bsCx or Bom-bsFCx, respectively) were used to pretarget PC-3 human prostate cancer xenografts in SCID mice. Negative control mice were pretargeted with Bom or anti-DTPA Ab. 111 In-Labeled DTPA-succinyl polylysine (DSPL) was injected intravenously at 24 h (7.03 ± 1.74 or 6.88 ± 1.89 MBq 111 In-DSPL) after Bom-bsCx or 50 ± 5.34 MBq of 99m Tc-DSPL after Bom-bsFCx pretargeting, respectively. Planar or single photon emission computed tomography (SPECT)/CT gamma images were obtained for up to 3 h and only planar images at 24 h. After imaging, all mice were killed and biodistribution of 111 In or 99m Tc activities were determined by scintillation counting. Both planar and SPECT/CT imaging enabled detection of PC-3 prostate cancer lesions less than 1-2 mm in diameter in 1-3 h post 111 In-DSPL injection. No lesions were visualized in Bom or anti-DTPA Ab pretargeted controls. 111 In-DSPL activity in Bom-bsCx pretargeted tumors (1.21 ± 0.36%ID/g) was 5.4 times that in tumors pretargeted with

In vitro and in vivo properties of human/mouse chimeric monoclonal antibody specific for common acute lymphocytic leukemia antigen

International Nuclear Information System (INIS)

Saga, T.; Endo, K.; Koizumi, M.; Kawamura, Y.; Watanabe, Y.; Konishi, J.; Ueda, R.; Nishimura, Y.; Yokoyama, M.; Watanabe, T.

1990-01-01

A human/mouse chimeric monoclonal antibody specific for a common acute lymphocytic leukemia antigen was efficiently obtained by ligating human heavy-chain enhancer element to the chimeric heavy- and light-chain genes. Cell binding and competitive inhibition assays of both radioiodine and indium-111- (111In) labeled chimeric antibodies demonstrated in vitro immunoreactivity identical with that of the parental murine monoclonal antibodies. The biodistribution of the radiolabeled chimeric antibody in tumor-bearing nude mice was similar to that of the parental murine antibody. Tumor accumulation of radioiodinated parental and chimeric antibodies was lower than that of 111 In-labeled antibodies, probably because of dehalogenation of the radioiodinated antibodies. Indium-111-labeled chimeric antibody clearly visualized xenografted tumor. These results suggest that a human/mouse chimeric antibody can be labeled with 111 In and radioiodine without the loss of its immunoreactivity, and that chimeric antibody localizes in vivo in the same way as the parental murine antibody

An Ultrasensitive Electrochemical Immunosensor for Alpha-Fetoprotein Using an Envision Complex-Antibody Copolymer as a Sensitive Label

Science.gov (United States)

Xiong, Ping; Gan, Ning; Cao, Yuting; Hu, Futao; Li, Tianhua; Zheng, Lei

2012-01-01

A novel strategy is presented for sensitive detection of alfa-fetoprotein (AFP), using a horseradish peroxidase (HRP)-functionalized Envision antibody complex (EVC) as the label. The Envision-AFP signal antibody copolymer (EVC-AFP Ab2) was composed of a dextran amine skeleton anchoring more than 100 molecules of HRP and 15 molecules of secondary antibody, and acted as a signal tag in the immunosensor. The sensor was constructed using the following steps: First, gold electrode (GE) was modified with nano-gold (AuNPs) by electro-deposition in HAuCl4 solution. The high affinity of the AuNPs surface facilitates direct formation of a self-assembled thiolated protein G layer. Next, the coated GE was incubated in a solution of AFP capture antibody (AFP Ab1); these antibodies attach to the thiolated protein G layer through their non-antigenic regions, leaving the antigen binding sites for binding of target analyte. Following a sandwich immunoreaction, an EVC-AFP Ab2-AFP-AFP Ab1 immunocomplex was formed on the electrode surface, allowing large amounts of HRP on the complex to produce an amplified electrocatalytic current of hydroquinone (HQ) in the presence of hydrogen peroxide (H2O2). Highly amplified detection was achieved, with a detection limit of 2 pg/mL and a linear range of 0.005–0.2 ng/mL for AFP in 10 μL undiluted serum; this is near or below the normal levels of most cancer biomarker proteins in human serum. Measurements of AFP in the serum of cancer patients correlated strongly with standard enzyme-linked immunosorbent assays. These easily fabricated EVC-modified immunosensors show excellent promise for future fabrication of bioelectronic arrays. By varying the target biomolecules, this technique may be easily extended for use with other immunoassays, and thus represents a versatile design route.

Quinone-Based Polymers for Label-Free and Reagentless Electrochemical Immunosensors: Application to Proteins, Antibodies and Pesticides Detection

Directory of Open Access Journals (Sweden)

Minh-Chau Pham

2013-01-01

Full Text Available Polyquinone derivatives are widely recognized in the literature for their remarkable properties, their biocompatibility, simple synthesis, and easy bio-functionalization. We have shown that polyquinones present very stable electroactivity in neutral aqueous medium within the cathodic potential domain avoiding side oxidation of interfering species. Besides, they can act as immobilized redox transducers for probing biomolecular interactions in sensors. Our group has been working on devices based on such modified electrodes with a view to applications for proteins, antibodies and organic pollutants using a reagentless label-free electrochemical immunosensor format. Herein, these developments are briefly reviewed and put into perspective.

Labelling of anti-human bladder tumor chimeric antibody with 99Tcm and radioimmunoimaging of bladder carcinoma xenograft in nude mice

International Nuclear Information System (INIS)

Zhang Chunli; Wang Rongfu; Fu Zhanli; Bai Yin; Ding Yi; Yu Lizhang

2003-01-01

Objective: To study the in vitro immunoreactivity and in vivo tissue distribution, tumor targeting property of anti-human bladder tumor human-murine chimeric antibody (ch-BDI) labeled with 99 Tc m and to investigate its possibility for being used in guiding diagnosis and guiding therapy of bladder cancer. Methods: The ch-BDI was labeled with 99 Tc m by improved Schwarz method and the labeled antibody was purified by Sephadex G-50. Labeling yield and radiochemical purity were measured by paper chromatography. The immunoreactive fraction and association constant (K a ) were measured by Lindmo method and Scatchard analysis, respectively. 11.1 MBq (30 μg) 99 Tc m -ch-BDI was intravenously injected into nude mice bearing human bladder cancer xenografts in the right thigh and radioimmunoimaging (RII) was performed 2, 6, 20 and 24 h postinjection. The images were processed by region of interest (ROI) method to acquire the counts of whole body and the tumor and the counts ratios of tumor to contralateral normal tissue or to tissues of other non-tumor bearing organs. The mice were killed after 24 h postinjection imaging and tissue distribution was measured. %ID/g and target to nontarget (T/NT) ratios were calculated. Results: The labeling yield and radiochemical purity of 99 Tc m -ch-BDI were (66.5±7.3)% and >90%, respectively. The immunoreactive fraction was 76% and K a was 3.56 x 10 9 L/mol. RII showed that the tumor was clearly visualized 6 h postinjection and becoming clearer along with time prolonging. The radioactivity of whole body decreased rapidly with time, whereas the radioactivity of the tumor decreased slowly. The T/NT ratios was increased with time. Biodistribution results showed that tumor uptake was 17.4%ID/g 24 h postinjection. T/NT ratios were very high except for the kidney. T/NT ratios for brain, muscle, intestinal wall, bone and heart wall were 136.0, 55.1, 39.3, 29.7 and 27.9, respectively. Conclusion: 99 Tc m -ch-BDI exhibits excellent

A sensitive radioimmunoassay for the detection of monoclonal anti-idiotype antibodies

International Nuclear Information System (INIS)

Morahan, G.

1983-01-01

A radioimmunoassay was developed in order to detect anti-idiotypic antibodies in the supernatants of hybrid cells. This assay is both sensitive and specific for anti-idiotypic (but not anti-allotypic) antibodies. Monoclonal antibodies present in test supernatants are bound by an anti-immunoglobulin coated solid phase. Subsequent incubation with a source of mouse immunoglobulin 'blocks' unreacted anti-immunoglobulin antibodies on the solid phase. Anti-idiotypic antibodies are then detected by their ability to bind 125 I-labelled idiotype-bearing antibody. This paper describes the use of this assay to detect monoclonal anti-idiotypic antibodies in 2 systems; the cross-reactive idiotype of A/J anti-ABA antibodies, and the idiotype expressed by the myeloma protein HOPC 8. Similarly, 125 I-labelled anti-idiotype antibodies may be used in this assay to detect monoclonal idiotype-bearing antibodies. Further modifications are described which would allow the detection of monoclonal anti-allotype antibodies. (Auth.)

New sensitive and specific assay for human immunodeficiency virus antibodies using labeled recombinant fusion protein and time-resolved fluoroimmunoassay.

OpenAIRE

Siitari, H; Turunen, P; Schrimsher, J; Nunn, M

1990-01-01

A new, rapid method for the detection of human immunodeficiency virus type 1 (HIV-1) antibody by time-resolved fluoroimmunoassay (TR-FIA) was developed. In this assay format, microtitration strips were coated with a recombinant fusion protein, and the same protein was labeled with europium and added into the wells simultaneously with the test specimens. The recombinant fusion protein contained the HIV-1 p24 gag protein sequence that carried an insertion, near the carboxyl terminus, of a 23-am...

Design of a single-step immunoassay principle based on the combination of an enzyme-labeled antibody release coating and a hydrogel copolymerized with a fluorescent enzyme substrate in a microfluidic capillary device.

Science.gov (United States)

Wakayama, Hideki; Henares, Terence G; Jigawa, Kaede; Funano, Shun-ichi; Sueyoshi, Kenji; Endo, Tatsuro; Hisamoto, Hideaki

2013-11-21

A combination of an enzyme-labeled antibody release coating and a novel fluorescent enzyme substrate-copolymerized hydrogel in a microchannel for a single-step, no-wash microfluidic immunoassay is demonstrated. This hydrogel discriminates the free enzyme-conjugated antibody from an antigen-enzyme-conjugated antibody immunocomplex based on the difference in molecular size. A selective and sensitive immunoassay, with 10-1000 ng mL(-1) linear range, is reported.

The study of conjugation of anti-CD20 monoclonal antibody for labeling with metallic or lanthanides radionuclides; Estudo de conjugacao do anticorpo anti-CD20 para marcacao com radionuclideos metalicos ou lantanideos

Energy Technology Data Exchange (ETDEWEB)

Akanji, Akinkunmi Ganiyu

2012-07-01

Lymphomas are malignancies or cancers that start from the malign transformation of a lymphocyte in the lymphatic system. Generally, lymphomas start from the lymph nodes or from the agglomeration of the lymphatic tissues, organs like stomach, intestines, in some cases it can involve the bone marrow and the blood, it can also disseminate to other organs. Lymphomas are divided in two major categories: Hodgkin lymphoma and non-Hodgkin lymphoma (NHL). Patient with NHL are generally treated with radiotherapy alone or combined with immunotherapy using monoclonal antibody rituximab (MabThera Registered-Sign ). Currently, monoclonal antibodies (Acm) conjugated with bifunctional chelate agents and radiolabeled with metallic or lanthanides radionuclides are a treatment reality for patients with NHL by the principle of radioimmunotherapy (RIT). This study focused on the conditions of conjugation of Acm rituximab (MabThera Registered-Sign ) with bifunctional chelating agents DOTA and DTPA. Various parameters were studied: method of Acm purification, conditions of Acm conjugation, the method for determination of number of chelate agent coupled to the Acm, method for purification of the conjugated antibody Acm, conditions of labeling of the conjugated antibody with lutetium-177, method of purification of the radiolabeled immuno conjugate, method of radiochemical purity (RP), specific binding in vitro Raji cells (Human Burkitt) and biological distribution performed in normal Balb-c mouse. The three methodologies employed in pre-purification of Acm (dialysis, size exclusion chromatograph and dial filtration) demonstrated to be efficient; they provided sample recovery exceeding 90%. However, the methodology of dial filtration presents minimal sample loss, and gave the final recovery of the sample in micro liters; thereby facilitating sample use in subsequent experiments. Numbers of chelators attached to the Acm molecule was proportional to the molar ratio studied. When we evaluated

Experimental radioimmunoimaging of human lung small cell carcinoma xenograft H-69 by NCC-ST-433 monoclonal antibody

International Nuclear Information System (INIS)

Kubota, Tetsuro; Nakamura, Kayoko; Kubo, Atsushi; Hashimoto, Shozo; Watanabe, Masahiko; Ishibiki, Kyuya; Abe, Osahiko

1989-01-01

NCC-ST-433 monoclonal antibody raised against human gastric carcinoma xenograft (St-4) was labeled with l25 I using enzymatic and Iodogen methods. While labeling efficiency of the antibody was more excellent by enzymatic method, specific radioactivity of the antibody labeled by Iodogen method was higher than that by enzymatic method. The labeled antibody was stable in vitro and in vivo, and the labeled NCC-ST-433 was specifically accumulated in NCC-ST-433 antigen positive human tumor cell lines in vitro. The specificity of 125 I-NCC-ST-433 in vivo was found to be more excellent when this antibody was labeled by Iodogen method and acutually excellent images of H-69, a human small cell lung carcioma, were obtained 5 days after injection of 7 μg of 125 I-NCC-ST-433 per mouse. This method seemed to be promising for imaging human lung small cell carcinoma. (author)

Radiolabeled antibodies in cancer. Oncology Overview

International Nuclear Information System (INIS)

1984-11-01

Oncology Overviews are a service of the International Cancer Research Data Bank (ICRDB) Program of the National Cancer Institute, intended to facilitate and promote the exchange of information between cancer scientists by keeping them aware of literature related to their research being published by other laboratories through the world. Each Oncology Overview represents a survey of the literature associated with a selected area of cancer research. It contains abstracts of articles which have been selected and organized by researchers associated with the field. Contents: Radiolabeled antibodies--labeling and imaging techniques; Radiolabeled antibodies--carcinoembryonic antigen; Radiolabeled antibodies--alpha-fetoprotein; Radiolabeled antibodies--human chorionic gonadotropin; Radiolabeled antibodies--ferritin; Radiolabeled antibodies--imaging of colorectal tumors; Radiolabeled antibodies--imaging of malignant melanoma; Radiolabeled antibodies--imaging of urogenital tumors; Radiolabeled antibodies--imaging of thyroid tumors; Radiolabeled antibodies--other clinical studies; Radiolabeled antibodies--selected preclinical studies; Radiolabeled antibodies--reviews

Making Recombinant Monoclonal Antibody And Radiolabelling For Medical Purpose

International Nuclear Information System (INIS)

Nguyen Thi Thu; Duong Van Dong; Vo Thi Cam Hoa; Bui Van Cuong; Chu Van Khoa; Vu Bich Huong; Le Quang Huan

2008-01-01

Recombinant monoclonal antibody labeling with 131 I specific to tumor cell has been studied and prepared for treatment of Hodgkin lymphoma. In this study, a recombinant monoclonal antibody with two specific properties is a hybrid molecule created by coupling an antibody variable fragments with peptide melittin. The gene coding the antibody fragment has been obtained from human synthetic Fv libraries using for panning and screening on populations of lymphocytes fragmented from human blood cells with Hodgkin diseases. The gene encoding peptit melittin has been cloned from honeybee Apis cerana DNA. The gene coding recombinant monoclonal antibody has been expressed in E.coli BL21 (DE3) at 37 o C and was induced with 0.6 mM IPTG. The recombinant compound has been purified by affinity chromatography with HiTrap affinity column. The obtained recombinant monoclonal antibody has showed cytolytic activities when added to cell culture medium for LU cancer cell line with the amount of 100 - 200 mg/ml. This monoclonal antibody is labeled with 131 I using chloramine T procedure. ChT mass for the oxidation of 50 μg monoclonal antibody in 76 MBq was 10 μg. Sodium metabisulfite was used as a reducing agent. Reaction time was above 3 mins. The radiochemical purity was determined using electrophoresis and TLC methods. Radiochemical yield was > 97%. Radiochemical purity after purification was > 99%. Nuclear purity was > 99%. Stability of the label antibody was 12 days. This is the product promise potential used in the diagnostic and therapeutic of Hodgkin lymphoma. (author)

Radiolabeled antibody in the detection of infection using endocarditis as a model

International Nuclear Information System (INIS)

Mishkin, F.S.; Wong, D.W.; Dhawan, V.K.; Reese, I.C.; Thadepalli, H.

1983-01-01

The authors have examined a method to detect infections using radiolabeled antibodies. Staphylococcal endocarditis was chosen as a model because it poses a common clinical diagnostic problem. The experiments demonstrate that biologically active antibodies may be extracted and efficiently labeled by a relatively simple process. This has the potential to make the specificity of the in vivo antigen-antibody reaction available through the use of autologously extracted, labeled γ-globulin

Monoclonal antibody hapten radiopharmaceutical delivery

International Nuclear Information System (INIS)

Goodwin, D.A.; McTigue, M.

1986-01-01

One hundred μg of monoclonal antibody (MoAb) CHA255 with a binding constant Kb of 4 x 10 9 was complexed with indium-111 labelled BLEDTA II, BLEDTA IV, benzyl EDTA, and an EDTA conjugate of Fab. The 24-h tumour and organ distribution of BALB/c mice bearing KHJJ tumours was studied for each compound alone, the antibody complex, and 3 h following a chelate chase of the antibody complex. Whole body biological half-life was measured for 7 days with and without a chelate chase for each antibody complex. The 24-h whole body counts dropped 20 to 60% and blood concentration fell over 89% within 3 h of administering the chelate chase. Theoretical equivalent human organ doses were calculated from the 24-h organ concentrations, effective half-life, and MIRD 11 S values (absorbed dose per cumulated activity). Liver and spleen were the target organs, with the dose ranging from 0.50 to 3.91 rads mCi -1 . The reduction in organ radiation dose varied up to 95% following the chelate chase. Rapid selective renal clearance of chelate labelled radiopharmaceuticals by competitive inhibition (chelate chase) of their reversible binding to monoclonal antibodies enhances tumour imaging and improves the radiation dosimetry. (author)

Boronated monoclonal antibody conjugates for neutron capture therapy

International Nuclear Information System (INIS)

Borg, D.C.; Elmore, J.J. Jr.; Ferrone, S.

1986-01-01

This paper describes the effectiveness of 10 B-labeled monoclonal antibodies against Colo-38 human melanoma in vitro. The authors obtained high boron to antibody ratios while maintaining antibody activity by using dextran intermediate carriers to link 10 B to the antibody. They developed a double cell quasi-competitive binding bioassay to minimize the effects of nonspecific binding of boronated complexes to cells. 1 fig., 2 tabs

Localisation of cancer of the ovary and metastases using 123I-labelled monoclonal antibody HMFG-2 compared to surgical findings

International Nuclear Information System (INIS)

Britton, K.E.; Granowska, M.; Shepherd, J.

1985-01-01

The value of radioimmunoscintigraphy is investigated in the localization of cancer of the ovary and metastases using 123 I-labelled monoclonal antibody HMFG-2 compared to surgical findings. The results show that the HMFG-2 imaging is good in staging and determining the results of chemotherapy in known ovarian cancer but poor in screening patients presenting with a pelvic mass or those with carcinoma of the ovary. The requirements for improvements in radioimmunoscintigraphy are discussed. (UK)

Safety and Efficacy of 188-Rhenium-Labeled Antibody to Melanin in Patients with Metastatic Melanoma

Directory of Open Access Journals (Sweden)

M. Klein

2013-01-01

Full Text Available There is a need for effective “broad spectrum” therapies for metastatic melanoma which would be suitable for all patients. The objectives of Phase Ia/Ib studies were to evaluate the safety, pharmacokinetics, dosimetry, and antitumor activity of 188Re-6D2, a 188-Rhenium-labeled antibody to melanin. Stage IIIC/IV metastatic melanoma (MM patients who failed standard therapies were enrolled in both studies. In Phase Ia, 10 mCi 188Re-6D2 were given while unlabeled antibody preload was escalated. In Phase Ib, the dose of 188Re-6D2 was escalated to 54 mCi. SPECT/CT revealed 188Re-6D2 uptake in melanoma metastases. The mean effective half-life of 188Re-6D2 was 12.4 h. Transient HAMA was observed in 9 patients. Six patients met the RECIST criteria for stable disease at 6 weeks. Two patients had durable disease stabilization for 14 weeks and one for 22 weeks. Median overall survival was 13 months with no dose-limiting toxicities. The data demonstrate that 188Re-6D2 was well tolerated, localized in melanoma metastases, and had antitumor activity, thus warranting its further investigation in patients with metastatic melanoma.

Development of a new radiolabel (lead-203) and new chelating agents for labeling monoclonal anntibodies for imaging

International Nuclear Information System (INIS)

Srivastava, S.C.; Mease, R.C.; Meinken, G.E.; Mausner, L.F.; Steplewski, Z.

1988-01-01

High liver uptake and slow body clearance presently limit the usefulness of 111 In labeled antibodies for tumor imaging. We have investigated 203 Pb as an alternate and better antibody label. The DTPA and cyclohexyl EDTA (CDTA) conjugates of an anticolon carcinoma antibody, 17-1A were labeled (bicyclic anhydride method) with 203 Pb and 111 In with 60 and 90% labeling yields, respectively. The biodistribution of 203 Pb-17-1A conjugates was compared with the corresponding 111 In-labeled preparations and with 203 Pb-DTPA, 203 Pb-nitrate and nonrelevant antibody controls in normal and human tumor (SW948) xenografted nude mice at 24, and 96 hr. Lead-203-labeled CDTA and DTPA antibody conjugates gave similar in vivo distributions. Even though the lead bound to these chelate-antibody conjugates was more labile in serum and in vivo, compared to indium, it cleared much faster from the liver and the whole body. A new series of chelating agents based on the incorporation of a trans-1,2- diaminocyclohexane moiety into the carbon backbone of polyaminocarboxylates is being synthesized. These are expected to provide stronger complexing ability for lead and produce greater in vivo stability. These ligands are also expected to be superior to EDTA and DTPA for labeling antibodies with other radiometals, including indium. 32 refs., 3 tabs

Quantitative localization microscopy: effects of photophysics and labeling stoichiometry.

Directory of Open Access Journals (Sweden)

Robert P J Nieuwenhuizen

Full Text Available Quantification in localization microscopy with reversibly switchable fluorophores is severely hampered by the unknown number of switching cycles a fluorophore undergoes and the unknown stoichiometry of fluorophores on a marker such as an antibody. We overcome this problem by measuring the average number of localizations per fluorophore, or generally per fluorescently labeled site from the build-up of spatial image correlation during acquisition. To this end we employ a model for the interplay between the statistics of activation, bleaching, and labeling stoichiometry. We validated our method using single fluorophore labeled DNA oligomers and multiple-labeled neutravidin tetramers where we find a counting error of less than 17% without any calibration of transition rates. Furthermore, we demonstrated our quantification method on nanobody- and antibody-labeled biological specimens.

Enhanced tumor retention of a radiohalogen label for site-specific modification of antibodies.

Science.gov (United States)

Boswell, C Andrew; Marik, Jan; Elowson, Michael J; Reyes, Noe A; Ulufatu, Sheila; Bumbaca, Daniela; Yip, Victor; Mundo, Eduardo E; Majidy, Nicholas; Van Hoy, Marjie; Goriparthi, Saritha N; Trias, Anthony; Gill, Herman S; Williams, Simon P; Junutula, Jagath R; Fielder, Paul J; Khawli, Leslie A

2013-12-12

A known limitation of iodine radionuclides for labeling and biological tracking of receptor targeted proteins is the tendency of iodotyrosine to rapidly diffuse from cells following endocytosis and lysosomal degradation. In contrast, radiometal-chelate complexes such as indium-111-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (In-111-DOTA) accumulate within target cells due to the residualizing properties of the polar, charged metal-chelate-amino acid adduct. Iodine radionuclides boast a diversity of nuclear properties and chemical means for incorporation, prompting efforts to covalently link radioiodine with residualizing molecules. Herein, we describe the Ugi-assisted synthesis of [I-125]HIP-DOTA, a 4-hydroxy-3-iodophenyl (HIP) derivative of DOTA, and demonstration of its residualizing properties in a murine xenograft model. Overall, this study displays the power of multicomponent synthesis to yield a versatile radioactive probe for antibodies across multiple therapeutic areas with potential applications in both preclinical biodistribution studies and clinical radioimmunotherapies.

[Investigations into the use of radiolabeled monoclonal antibodies for selective cell labeling in whole blood]: Progress report, March 1985-May 1988

International Nuclear Information System (INIS)

Thakur, M.L.

1987-01-01

Seventeen monoclonal antibodies (MAbs), 7 specific for human platelets and 10 specific for human polumorphonuclear leukocytes (PMNs) have been evaluated. One MAb has been identified as the antibody most suitable for canine platelets and another has been evaluted as the best among the group, for human neutrophil studies. Indium-111, Tc-99m, and I-125 have been used as the tracers. Six bifunctional chelating agents (BFCAs) were evaluated in order to determine the most efficient agent for maximal cell labeling efficiency. Among these, the DTPA has given us the best results. (4) To botain maximum In-111 chelation and minimum loss of the MAb affinity, the optimal BFCA to MAb ratios for both IgG and IgM type of MAbs were determined. Four different substances, stannous chloride, ascorbic acid, sodium dithionite and sodium borohydride, were evaluated as reducing agents for Tc-99m reduction and its optimal binding to MAbs. Dithionite at the concentration of 200 ug/ml DTPA-MAb solution provides greater than 50% Tc-99m labeling efficiency and maintains its immunospecificity equal to that of In-111-DTPA-MAb. The ability of radiolabeled MAb to interact with blood cells selectively in whole blood and with isolated blood cells was assessed and compared

Clinical use of antibodies

International Nuclear Information System (INIS)

Baum, R.P.; Hoer, Gustav; Cox, P.H.; Buraggi, G.L.

1991-01-01

Use of monoclonal antibodies as tumour specific carrier molecules for therapeutic agents or as in vivo diagnostic reagents when labelled with radionuclides or NMR signal enhancers is attracting more and more attention. The potential is enormous but the technical problems are also considerable requiring the concerted action of many different scientific disciplines. This volume is based upon a symposium organised in Frankfurt in 1990 under the auspices of the European Association of Nuclear Medicines' Specialist Task Groups on Cardiology and the Utility of Labelled Antibodies. It gives a multidisciplinary review of the state of the art and of problems to be solved as well as recording the not inconsiderable successes which have been booked to date. The book will be of value as a reference to both clinicians and research scientists. refs.; figs.; tabs

An antibody toolkit for the study of membrane traffic in Drosophila melanogaster

Directory of Open Access Journals (Sweden)

Falko Riedel

2016-07-01

Full Text Available The use of Drosophila melanogaster as a model organism has been pivotal to understanding the developmental processes of metazoans. However, the use of flies for studying subcellular organization is hampered by a paucity of reliable reagents to label specific organelles. Here, we describe the generation of mouse monoclonal antibodies against a set of markers of the secretory and endocytic pathways, along with goat polyclonal antibodies against two Golgi proteins. We show that the monoclonal antibodies are highly specific and sufficiently sensitive to detect endogenous proteins in crude extracts by immunoblotting with little background staining. By immunofluorescence the major compartments of the membrane traffic system (including the endoplasmic reticulum, the Golgi, and early and late endosomes are labeled by at least one antibody. Moreover, the antibodies can be used to label organelles in fly tissues including salivary glands and wing imaginal discs. We anticipate that these antibodies will provide a useful tool kit to facilitate the investigation of how the endomembrane system functions and varies in the diverse tissue types of metazoans.

Basic studies on the tumor imaging using antibodies to human alpha-fetoprotein

International Nuclear Information System (INIS)

Sakahara, Harumi; Endo, Keigo; Nakashima, Tetsuo; Ohta, Hitoya; Torizuka, Kanji

1984-01-01

Using polyclonal antibodies to human α-fetoprotein (AFP), the effect of iodination on the antibody activity and tumor accumulation of radioiodinated antibodies in tumor bearing nude mice were examined. Antibodies, obtained from horse antiserum and purified by affinity chromatography, were iodinated by the chloramine-T method and their antibody activity was evaluated using RIA and Scatchard plot analysis. When high concentrations of chloramine-T were used or more than 2.6 iodine atoms were incorporated per antibody molecule, the antigen binding capacity rather than the affinity constant was affected by the iodination. The antibody activity was completely destroyed at an iodine to antibody molar ratio of 15.4. Antibodies, however, which were iodinated under low concentrations of chloramine-T and contained less than 0.8 iodines per antibody molecule, showed almost full retention of their antibody activity. Nude mice transplanted with AFP producing human testicular tumor or AFP non-producing human urinary bladder tumor were administered intravenously with 131 I-labeled antibodies to human AFP. Scintigrams were taken at 1, 2, 4 and 7 days after the injection of labeled antibodies. At day 7, nude mice were sacrificed and organs and tumor were removed, weighed and counted. In nude mice bearing testicular tumor, tumor image became gradually clear with decreasing background activity and tumor to blood ratio, obtained, was 0.82 for testicular tumor compared to 0.42 for bladder tumor. These results indicated a specific in vivo localization of 131 I-labeled antihuman AFP antibodies in AFP producing tumor. (author)

THE EFFECT OF LABELING INTENSITY, ESTIMATED BY REAL-TIME CONFOCAL LASER SCANNING MICROSCOPY, ON FLOW CYTOMETRIC APPEARANCE AND IDENTIFICATION OF IMMUNOCHEMICALLY LABELED MARINE DINOFLAGELLATES

NARCIS (Netherlands)

VRIELING, EG; DRAAIJER, A; VANZEIJL, WJM; PEPERZAK, L; GIESKES, WWC; VEENHUIS, M; Zeijl, Wilhelmus J.M. van

Two different fluorescein isothiocyanate (FITC) conjugates were used to analyze the effect of labeling intensity on the flow cytometric appearance of marine dinoflagellates labeled with antibodies that specifically recognized the outer cell wall. Location of the labeling was revealed by

Monoclonal anti-melanoma antibodies and their possible clinical use

International Nuclear Information System (INIS)

Hellstroem, K.E.; Hellstroem, Ingegerd; Washington Univ., Seattle; Washington Univ., Seattle

1985-01-01

Cell surface antigens of human melanoma, as defined by monoclonal antibodies, are discussed and in particular the three antigens p97, a GD3 ganglioside and a proteoglycan. The potential diagnostic uses of antibodies to melanoma antigens are reviewed including in vitro diagnosis by immuno-histology, in vitro diagnosis by serum assays and in vivo diagnosis by tumour imaging using radioactively labelled antibodies. The potential therapeutic uses of monoclonal antibodies to melanoma antigens are also reviewed including targets for antibody therapy, the use of antibodies alone, radiolabelled antibodies, antibody-toxin conjugates, antibody-drug conjugates, anti-idiotypic antibodies and vaccines. (UK)

[3H]Azidodantrolene photoaffinity labeling, synthetic domain peptides and monoclonal antibody reactivity identify the dantrolene binding sequence on RyR1

Energy Technology Data Exchange (ETDEWEB)

Paul-Pletzer, Kalanethee; Yamamoto, Takeshi; Bhat, Manju B.; Ma, Jianjie; Ikemoto, Noriaki; Jimenez, Leslie S.; Morimoto, Hiromi; Williams, Philip G.; Parness, Jerome

2002-06-14

Dantrolene is a drug that suppresses intracellular Ca2+ release from sarcoplasmic reticulum in normal skeletal muscle and is used as a therapeutic agent in individuals susceptible to malignant hyperthermia. Though its precise mechanism of action has not been elucidated, we have identified the N-terminal region (amino acids 1-1400) of the skeletal muscle isoform of the ryanodine receptor (RyR1), the primary Ca2+ release channel in sarcoplasmic reticulum, as a molecular target for dantrolene using the photoaffinity analog [3H]azidodantrolene(1). Here, we demonstrate that heterologously expressed RyR1 retains its capacity to be specifically labeled with [3H]azidodantrolene,indicating that muscle specific factors are not required for this ligand-receptor interaction. Synthetic domain peptides of RyR1, previously shown to affect RyR1 function in vitro and in vivo, were exploited as potential drug binding site mimics and used in photoaffinity labeling experiments. Only DP1 and DP1-2, peptide s containing the amino acid sequence corresponding to RyR1 residues 590-609, were specifically labeled by [3H]azidodantrolene. A monoclonal anti-RyR1 antibody which recognizes RyR1 and its 1400 amino acid N-terminal fragment, recognizes DP1 and DP1-2 in both Western blots and immunoprecipitation assays, and specifically inhibits [3H]azidodantrolene photolabeling of RyR1 and its N-terminal fragment in sarcoplasmic reticulum. Our results indicate that synthetic domain peptides can mimic a native, ligand binding conformation in vitro, and that the dantrolene binding site and the epitope for the monoclonal antibody on RyR1 are equivalent and composed of amino-acids 590-609.

Antibody Based Surgical Imaging and Photodynamic Therapy for Cancer

NARCIS (Netherlands)

de Boer, Esther

2016-01-01

In 1944 Albert Coons was the first to show that a fluorescent molecule could be conjugated directly to an antibody made against a target site of interest. This binding does not affect antibody specificity so that labeled antibodies can be used to visualize the location and distribution of the target

Radioimmunoassay of class-specific antibodies (RIACA): chicken antibodies to DNP

International Nuclear Information System (INIS)

Viljanen, M.K.; Granfors, K.; Toivanen, P.

1977-01-01

A radioimmunological method for the quantitation of class-specific antibodies has been developed. The method allows the quantitation of nanogram per ml concentrations of IgG and IgM-anti-DNP antibodies without any physical or chemical pretreatment of the sample. DNP was coupled covalently to a cyanogen bromide activated paper disk with the augmentation of lysine molecule. Anti-DNP antibodies were allowed to react with the coupled DNP and then quantitated by their capacity to bind 125 I-labelled anti-chicken-μ or anti-chicken-γ. The inter-assay variation coefficients ranged from 8.1 to 14.7% and the mean standard deviations of duplicate determinations were about 11%. The combination of this method with the exact immunoradiometric quantitation of the total serum IgM and IgG, and with an immunoabsorption technique, makes it possible to quantitate class-specific antibodies on weight units

Composition and method for detecting cancer with technetium labeled antibody fragments

International Nuclear Information System (INIS)

Burchiel, S. W.; Crockford, D. R.; Rhodes, B. A.

1984-01-01

F(ab') 2 or Fab fragments of antibodies to: (a) human chorionic gonadotropin (hCG), hCG alpha subunit, hCG beta subunit, or an hCG-like material; or (b) other tumor specific or tumor associated molecules, to include carcinoembryonic antigen (CEA), alpha fetoprotein (AFP), human melanoma associated antigens, human sarcoma associated antigens or other antigens, are radiolabeled with technetium-99m (Tc-99m). When the F(ab') 2 or Fab fragments of antibody to such tumor associated antigens are injected intravenously into a patient, the radiolabeled composition accumulates at tumor sites. The accumulation of the cancer seeking radiopharmaceutical at tumor sites permits detection by external gamma scintigraphy. Thus, the composition is useful in the monitoring, localization and detection of cancer in the body. In an alternative composition, a double antibody approach to tumor localization using radiolabeled F(ab') 2 or Fab fragments is utilized. In this approach, a tumor specific antibody in the form of IgG, F(ab') 2 or Fab is first administered to a patient intravenously. Following a sufficient period of time, a second antibody in the form of F(ab') 2 or Fab is administered. The second antibody is radiolabeled with Tc-99m and has the property that it is reactive with the first antibody. This double antibody method has the advantage over a single antibody approach in that smaller tumors can be localized and detected and that the total amount of radioactive trace localized at the cancer site is increased

Functionalized Polymer Microgel Particles Enable Customizable Production of Label-Free Sensor Arrays.

Science.gov (United States)

Lifson, Mark A; Carter, Jared A; Miller, Benjamin L

2015-08-04

Probe molecule immobilization onto surfaces is a critical step in the production of many analytical devices, including labeled and label-free microarrays. New methods to increase the density and uniformity of probe deposition have the potential to significantly enhance the ultimate limits of detection and reproducibility. Hydrogel-based materials have been employed in the past to provide a 3D protein-friendly surface for deposition of antibodies and nucleic acids. However, these methods are susceptible to variation during polymerization of the hydrogel scaffold and provide limited opportunities for tuning deposition parameters on an antibody-by-antibody basis. In this work, a versatile hydrogel nanoparticle deposition method was developed for the production of label-free microarrays and tested in the context of antibody-antigen binding. Poly(N-isopropylacrylamide) nanoparticles (PNIPAM) were conjugated to antibodies using an avidin/biotin system and deposited onto surfaces using a noncontact printing system. After drying, these gel spots formed uniform and thin layers <10 nm in height. The conjugates were characterized with dynamic light scattering, scanning electron microscopy, and atomic force microscopy. We tested this format in the context of tumor necrosis factor-alpha (TNF-α) detection via arrayed imaging reflectometry (AIR), a label-free protein microarray method. This method of probe molecule deposition should be generally useful in the production of microarrays for label-free detection.

Antibody guided diagnosis and therapy of brain gliomas using radiolabeled monoclonal antibodies against epidermal growth factor receptor and placental alkaline phosphatase

International Nuclear Information System (INIS)

Kalofonos, H.P.; Pawlikowska, T.R.; Hemingway, A.

1989-01-01

Twenty-seven patients with brain glioma were scanned using 123 I-labeled monoclonal antibodies against epidermal growth factor receptor (EGFR1) or placental alkaline phosphatase (H17E2). Successful localization was achieved in 18 out of 27 patients. Eleven out of 27 patients were also studied using a nonspecific control antibody (11.4.1) of the same immunoglobulin subclass and observable tumor localization was also achieved in five patients. The specificity of targeting was assessed by comparing images obtained with specific and nonspecific antibodies and by examining tumor and normal tissue biopsies after dual antibody administration. Ten patients with recurrent grade III or IV glioma who showed good localization of radiolabeled antibody were treated with 40-140 mCi of 131 I-labeled antibody delivered to the tumor area intravenously (n = 5) or by infusion into the internal carotid artery (n = 5). Six patients showed clinical improvement lasting from 6 mo to 3 yr. One patient continues in remission (3 yr after therapy), but the other five who responded initially relapsed 6-9 mo after therapy and died. No major toxicity was attributable to antibody-guided irradiation. Targeted irradiation by monoclonal antibody may be clinically useful and should be explored further in the treatment of brain gliomas resistant to conventional forms of treatment

Structural Characterization of Peptide Antibodies

DEFF Research Database (Denmark)

Chailyan, Anna; Marcatili, Paolo

2015-01-01

The role of proteins as very effective immunogens for the generation of antibodies is indisputable. Nevertheless, cases in which protein usage for antibody production is not feasible or convenient compelled the creation of a powerful alternative consisting of synthetic peptides. Synthetic peptides...... can be modified to obtain desired properties or conformation, tagged for purification, isotopically labeled for protein quantitation or conjugated to immunogens for antibody production. The antibodies that bind to these peptides represent an invaluable tool for biological research and discovery....... To better understand the underlying mechanisms of antibody-antigen interaction here we present a pipeline developed by us to structurally classify immunoglobulin antigen binding sites and to infer key sequence residues and other variables that have a prominent role in each structural class....

Apoptotic Effect of Anti myeloma Polyclonal Antibodies on The Growth of Myeloma Cells

International Nuclear Information System (INIS)

Abd El-Ghany, I.Y.; El-Kolaly, M.T.; Moustafa, K.A.; El-Shershaby, H.M.; Sayed, A.A.; Borai, I.H.; El-Lahloby, N.M.

2013-01-01

Multiple myeloma (MM) is a malignancy characterized by proliferation of plasma cells. Cancer immunotherapy is a major branch of biological therapy that utilizes living cells and their products. The aim of this study is to produce and evaluate the antiproliferative effect of anti myeloma polyclonal antibodies (with and without labelling with radioactive isotopes) against the growth of myeloma cells. The production of polyclonal antibodies (PAb) was generated by immunizing five healthy female mature white New-Zealand rabbits with myeloma cells (SP2/OR) through primary injection and five booster doses. The preparation of labelled anti myeloma antibodies was carried out using chloramine-T method and it was purified using PD-10 chromatographic column. The results obtained revealed that anti myeloma polyclonal antibodies inhibited proliferation and induced apoptosis of myeloma cell lines in vitro and induced apoptosis after serial intraperitoneal injection of PAb in ascites bearing mice in vivo. The present study suggested that the effect of labelled anti myeloma antibodies on myeloma cells growth inhibition was more effective than that of anti myeloma antibodies without labelling which is due to the cytotoxic effect of ionizing radiation. Apoptosis triggered by PAb was confirmed by flow cytometry, caspase -8 and -9 and β2-microglobulin.

Anti-fibrin antibody binding in valvular vegetations and kidney lesions during experimental endocarditis.

Science.gov (United States)

Yokota, M; Basi, D L; Herzberg, M C; Meyer, M W

2001-01-01

In Streptococcus sanguinis (sanguis) induced experimental endocarditis, we sought evidence that the development of aortic valvular vegetation depends on the availability of fibrin. Endocarditis was induced in New Zealand white rabbits by catheter placement into the left ventricle and inoculation of the bacteria. Fibrin was localized in the developing vegetation with 99mTechnetium (Tc)-labeled anti-fibrin antibody one or three days later. When rabbit anti-fibrin antibody was given intravenously on day 1, the mass of aortic valvular vegetation was significantly reduced at day 3; infusion of non-specific rabbit IgG showed no effect. The 99mTc-labeled anti-fibrin antibody also labeled kidneys that showed macroscopic subcapsular hemorrhage. To learn if the deposition of fibrin in the kidneys was a consequence of endocarditis required a comparison of farm-bred and specific pathogen-free rabbits before and after the induction of endocarditis. Before induction, the kidneys of farm-bred rabbits were labeled, but specific pathogen-free rabbits were free of labeling and signs of macroscopic hemorrhage. After 3 days of endocarditis, kidneys of 10 of 14 specific pathogen-free rabbits labeled with 99mTc-labeled anti-fibrin antibody and showed hemorrhage. Kidney lesions were suggested to be a frequent sequellae of S. sanguinis infective endocarditis. For the first time, fibrin was shown to be required for the continued development of aortic valvular vegetations.

Site-specifically {sup 89}Zr-labeled monoclonal antibodies for ImmunoPET

Energy Technology Data Exchange (ETDEWEB)

Tinianow, Jeff N.; Gill, Herman S.; Ogasawara, Annie; Flores, Judith E.; Vanderbilt, Alexander N.; Luis, Elizabeth; Vandlen, Richard; Darwish, Martine; Junutula, Jagath R.; Williams, Simon-P. [Genentech Research and Early Development, Genentech Inc., South San Francisco, CA 94080 (United States); Marik, Jan [Genentech Research and Early Development, Genentech Inc., South San Francisco, CA 94080 (United States)], E-mail: marik.jan@gene.com

2010-04-15

Three thiol reactive reagents were developed for the chemoselective conjugation of desferrioxamine (Df) to a monoclonal antibody via engineered cysteine residues (thio-trastuzumab). The in vitro stability and in vivo imaging properties of site-specifically radiolabeled {sup 89}Zr-Df-thio-trastuzumab conjugates were investigated. Methods: The amino group of desferrioxamine B was acylated by bromoacetyl bromide, N-hydroxysuccinimidyl iodoacetate, or N-hydroxysuccinimidyl 4-[N-maleimidomethyl]cyclohexane-1-carboxylate to obtain thiol reactive reagents bromoacetyl-desferrioxamine (Df-Bac), iodoacetyl-desferrioxamine (Df-Iac) and maleimidocyclohexyl-desferrioxamine (Df-Chx-Mal), respectively. Df-Bac and Df-Iac alkylated the free thiol groups of thio-trastuzumab by nucleophilic substitution forming Df-Ac-thio-trastuzumab, while the maleimide reagent Df-Chx-Mal reacted via Michael addition to provide Df-Chx-Mal-thio-trastuzumab. The conjugates were radiolabeled with {sup 89}Zr and evaluated for serum stability, and their positron emission tomography (PET) imaging properties were investigated in a BT474M1 (HER2-positive) breast tumor mouse model. Results: The chemoselective reagents were obtained in 14% (Df-Bac), 53% (Df-Iac) and 45% (Df-Chx-Mal) yields. Site-specific conjugation of Df-Chx-Mal to thio-trastuzumab was complete within 1 h at pH 7.5, while Df-Iac and Df-Bac respectively required 2 and 5 h at pH 9. Each Df modified thio-trastuzumab was chelated with {sup 89}Zr in yields exceeding 75%. {sup 89}Zr-Df-Ac-thio-trastuzumab and {sup 89}Zr-Df-Chx-Mal-thio-trastuzumab were stable in mouse serum and exhibited comparable PET imaging capabilities in a BT474M1 (HER2-positive) breast cancer model reaching 20-25 %ID/g of tumor uptake and a tumor to blood ratio of 6.1-7.1. Conclusions: The new reagents demonstrated good reactivity with engineered thiol groups of trastuzumab and very good chelation properties with {sup 89}Zr. The site-specifically {sup 89}Zr-labeled thio-antibodies

Search for new and improved radiolabeling methods for monoclonal antibodies

International Nuclear Information System (INIS)

Hiltunen, J.V.

1993-01-01

In this review the selection of different radioisotopes is discussed as well as the various traditional or newer methods to introduce the radiolabel into the antibody structure. Labeling methods for radiohalogens, for technetium and rhenium isotopes, and for 3-valent cation radiometals are reviewed. Some of the newer methods offer simplified labeling procedures, but usually the new methods are more complicated than the earlier ones. However, new labeling methods are available for almost any radioelement group and they may result in better preserved original natural of the antibody and lead to better clinical results. (orig./MG)

Radioiodine labelling of insulin using dimethylsulfoxide as a labelling-aid

Energy Technology Data Exchange (ETDEWEB)

Kim, J; Kim, Y H [Korea Atomic Energy Research Inst., Seoul, (Republic of Korea)

1977-12-01

Using dimethylsulfoxide (DMSO) as a labelling aid, insulin /sup 126/I of radioimmunoassay use has been effectively prepared. A small amount of DMSO was added to usual labelling mixture and the reaction time was controlled. The labelled insulin obtained in such a way showed improved bindabilities to the antibody and thus expressed larger dose-gradients in the plots of standard dose-response curves even though the labelling rate was decreased to some extent. However, by extending the reaction time to about 1 min, average labelling yield of 30% could be obtained. The average increase of bindability (B/F) in definite antiserum dilution was 2.5 compared with 1.5 obtained in the absence of DMSO. Thus, the net bindability increase was 70% of those obtained in the absence of DMSO. By means of NMR spectrometry, it has been confirmed that the DMSO in the labelling mixture is converted to dimethylsulfone by chloramine-T. The results, generally agreed with the Stagg's postulation, were discussed in view of a competitive oxidation of DMSO with disulfide linkages of the insulin molecule by the chloramine-T.

Development of labelled biomolecules for targeted radiotherapy

International Nuclear Information System (INIS)

Arteaga de Murphy, C.

2000-01-01

The scope of the co-ordinated research project (Dec 15 1997) included the following activities: 1) develop coupling techniques using bifunctional chelating agents for monoclonal antibodies and peptides, 2) optimised radiolabelling procedures and reaction parameters using Sm-153 and Re-188, 3) investigate direct methods of labelling monoclonal antibodies and peptides with Re-188. 4) initiate animal distribution studies. The modifications specified for the period 1999/02/15 to 2000/02/14 are as follows: a) continue with the optimisation of Re-188-peptide labelling, b) continue with the work to prepare a kit, c) in-vivo and in-vitro studies, d) lanreotide labelling. The group formed by researchers from several Mexican Institutions have worked together and in different aspects of the CRP in order to fulfil the proposed aims (our published work listed)

Development of labelled biomolecules for targeted radiotherapy

Energy Technology Data Exchange (ETDEWEB)

Arteaga de Murphy, C [Instituto Nacional de la Nutricion Salvador Zubiran, Departmento de Medicina Nuclear, Mexico D.F. (Mexico). E-mail: cmurphy at data.net.mx

2000-07-01

The scope of the co-ordinated research project (Dec 15 1997) included the following activities: 1) develop coupling techniques using bifunctional chelating agents for monoclonal antibodies and peptides, 2) optimised radiolabelling procedures and reaction parameters using Sm-153 and Re-188, 3) investigate direct methods of labelling monoclonal antibodies and peptides with Re-188. 4) initiate animal distribution studies. The modifications specified for the period 1999/02/15 to 2000/02/14 are as follows: a) continue with the optimisation of Re-188-peptide labelling, b) continue with the work to prepare a kit, c) in-vivo and in-vitro studies, d) lanreotide labelling. The group formed by researchers from several Mexican Institutions have worked together and in different aspects of the CRP in order to fulfil the proposed aims (our published work listed)

Detection of analyte binding to microarrays using gold nanoparticle labels and a desktop scanner

DEFF Research Database (Denmark)

Han, Anpan; Dufva, Martin; Belleville, Erik

2003-01-01

on gold nanoparticle labeled antibodies visualized by a commercial, office desktop flatbed scanner. Scanning electron microscopy studies showed that the signal from the flatbed scanner was proportional to the surface density of the bound antibody-gold conjugates, and that the flatbed scanner could detect...... six attomoles of antibody-gold conjugates. This detection system was used in a competitive immunoassay to measure the concentration of the pesticide metabolite 2,6-dichlorobenzamide (BAM) in water samples. The results showed that the gold labeled antibodies functioned comparably with a fluorescent...... based immunoassay for detecting BAM in water. A qualitative immunoassay based on gold-labeled antibodies could determineif a water sample contained BAM above and below 60-70 ng L(-1), which is below the maximum allowed BAM concentration for drinking water (100 ng L(-1)) according to European Union...

A new method for the labelling of proteins with radioactive arsenic isotopes

Energy Technology Data Exchange (ETDEWEB)

Jennewein, M. [Institute of Nuclear Chemistry, Johannes Gutenberg University of Mainz, Fritz-Strassmann-Weg 2, 55128 Mainz (Germany); Hermanne, A. [VUB Cyclotron, University of Brussels, Laarbeeklaan 103, 1090 Brussels (Belgium); Mason, R.P. [Department of Radiology, Advanced Radiological Sciences, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas (United States); Thorpe, P.E. [Department of Pharmacology and Simmons and Hamon Cancer Centers, University of Texas Southwestern Medical Center at Dallas, Dallas, TX (United States); Roesch, F. [Institute of Nuclear Chemistry, Johannes Gutenberg University of Mainz, Fritz-Strassmann-Weg 2, 55128 Mainz (Germany)]. E-mail: frank.roesch@uni-mainz.de

2006-12-20

Radioarsenic labelled radiopharmaceuticals could be a valuable asset to positron emission tomography. In particular, the long half-lives of {sup 72}As (T{sub 1/2}=26h) and {sup 74}As (T{sub 1/2}=17.8d) allow to investigate slow physiological or metabolical processes, like the enrichment and distribution of monoclonal antibodies (mab) in tumour tissue. In this work, a new method for the labelling of proteins with various radioactive arsenic isotopes was developed. For this purpose, two proteins, namely a chimeric IgG{sub 3} monoclonal antibody, ch3G4, directed against anionic phospholipids, and Rituxan (Rituximab), were labelled as a proof of principle with no-carrier-added radioarsenic isotopes ({sup 74}As and {sup 77}As). The developed labelling chemistry gives high yields (>99.9%), is reliable and could easily be transferred to automated labelling systems in a clinical environment. At least for the mab used in this work, this route of radioarsenic labelling does not affect the immunoreactivity of the product. The arsenic label stays stable for up to 72h at the molecular mass of the monoclonal antibody, which is in particular relevant to follow the pharmacology and pharmacokinetics of the labelled mab for several days.

A sandwich immunoassay for human prolyl 4-hydroxylase using monoclonal antibody

International Nuclear Information System (INIS)

Yoshida, Shinichi

1986-01-01

Monoclonal antibody was used in a sandwich enzyme immunoassay and in a radioimmunoassay for human serum immunoreactive prolyl 4-hydroxylase. The enzyme immunoassay utilized a monoclonal antibody as a solid phase and horseradish peroxidase-labeled rabbit antibody to human prolyl 4-hydroxylase as a conjugate. Sensitivity was 0.1 ng of enzyme per tube. With a conjugate purified by an enzyme-bound affinity column, sensitivity was increased to 0.01 ng per tube, and linearity was obtained between 0.01 to 30 ng per tube. The radioimmunoassay used a 125 I-labeled rabbit antibody (IgG) as the conjugate. Sensitivity of this technique was 0.4 ng of enzyme per tube. (Auth.)

A novel technetium-99m labeled monoclonal antibody (174H.64) for staging head and neck cancer by immuno-SPECT

International Nuclear Information System (INIS)

Baum, R.P.; Adams, S.; Kiefer, J.; Niesen, A.; Knecht, R.; Howaldt, H.P.; Hertel, A.; Adamietz, I.A.; Sykes, T.; Boniface, G.R.; Noujaim, A.A.; Hoer, G.

1993-01-01

A novel murine monoclonal antibody (MAb 174H.64) was labeled with 99m Tc by a direct method. MAb 174H.64 detects a cytokeratin-associated antigen which is expressed by over 90% of all squamous cell carinomas. Panendoscopy, sonography and computerized tomography scan were performed in all cases as well as magnetic resonance imaging (in selected patients). Pre-operative immunoscintigraphy was performed in 21 patients with histologically proven primary carcinomas (18 with remaining primary tumors and 3 with lymph node recurrences). Scintigraphic images were obtained 4-6 h after injection of 1.1 GBq of the 99m Tc-labeled antibody (2 mg). Late images were acquired 18 to 24 h after injection. Single-Photon-Emission-Computed Tomography (SPECT) of the head and thorax was performed in all patients. The primary tumors were immunoscintigraphically visualized in all 18 patients with remaining primary tumor. Fifteen of 18 loco-regional lymph node metastases were visualized by immunoscintigraphy (the smallest lesions had a diameter of <1 cm), in one patient lymph node metastases were detected by immunoscan only. Two metastatically involved lymph nodes were identified by histology only (micrometastases). Distant metastases were present in 3 patients, of which two were identified by immunoscintigraphy. Immuno-SPECT according to this method was a sensitive and specific imaging modality for preoperative staging of patients with squamous cell carcinoma of the head and neck and detected lymph node metastases with higher accuracy than conventional clinical and imaging modalities. (orig.)

Localization of radioiodinated antibody to alpha-fetoprotein in rats with transplanted hepatocellular carcinoma

Energy Technology Data Exchange (ETDEWEB)

Koji, T; Ishii, N; Munehisa, T; Kusumoto, Y; Nakamura, S; Tamenishi, A [Nagasaki Univ. (Japan). School of Medicine; Kobayashi, K; Hara, A; Tsukada, Y; Nishi, S

1980-01-01

Total body scintigraphy, organ and subcellular distribution of radioactivity and autoradiography of tissue sections has been assessed in an animal model using radioiodinated horse antibody to rat alpha-fetoprotein (AFP). Rats bearing subcutaneous transplants of AH-7974 ascites hepatoma were injected with /sup 125/I-labeled anti-AFP and scintigraphed. Localization of radioactivity in the tumors was observed 48-168 h after injection. Scintigraphy using /sup 125/I-labeled F(ab')/sub 2/ fragment of the antibody gave approximately the same results as that with the intact anti-AFP antibody. /sup 125/I-labeled normal horse IgG was used as control. The tumor/blood radioactivity ratio after a week after injection was approximately four times higher in the antibody group than that in the control group. This ratio suggested an active accumulation of radioactive antibody in the tumor tissue. In its subcellular distribution, about 30 to 60% of the total radioactivity administered was found in a fraction of the cell membrane plus nucleus. The specific activity of this fraction increased in the antibody group with time over 10 days. In autoradiograms of the fixed tissue sections specific localization of the antibody was observed on the tumor cell surface. The specific uptake of radiolabeled antibody to AFP into AFP producing tumor cells was confirmed.

Radioimmunotherapy of Nude Mice Bearing Human Colon Carcinoma with I-131 Labeled Anti-carcinoembryonic Antigen

International Nuclear Information System (INIS)

Kim, Byung Tae; Lee, Kyung Han; Kim, Sang Eun; Choi, Yong; Chi, Dae Yoon; Chung, June Key; Lee, Myung Chul; Koh, Chang Soon; Chung, Hong Keun

1995-01-01

This study was designed to evaluate the effects of various factors on the therapeutic effect of the I-l3l labeled anti-carcinoembryonic antigen monoclonal antibody(anti-CEA antibody). Tetrazolium-based colorimetric assay (MTT) was used to compare in vitro cytotoxicity of 3 Korean colon cancer cell lines (SNU-C2A, SNU-C4, SNU-C5) for selection of proper 2 cell lines in this study. The changes of the size of tumor which was xenografted to nude mice (balb/c nu/nu) were compared in 4 groups (group treated I-131 labeled anti-CEA antibody, group treated with non-radiolabeled anti-CEA antibody, group treated with I-131. labeled anti-human chorionic gonadotropin monoclonal antibody (anti-hCG antibody) as nonspecific antibody, and group injected with normal saline as a control). Immunohistochemical staining and in vivo autoradiography were performed after excision of the xenografted tumor. The results were as below mentioned. The in vitro cytotoxic effect of I-131 labeled anti-CEA antibody is most prominent in SNU-C5 cell line between 3 cancer cell lines. The changes of xenografted tumor size in both SNU-C4 and SNU-C5 cell tumors at the thirteenth day after injection of the antibodies were smallest in the group treated with I-131 labeled anti-CEA antibody (SNU-C4/SNU-C5; 324/342%) comparing with other groups, group treated with anti-CEA antibody (622/660%), group treated with I-131 anti-hCG antibody (538/546%), and control group(1030/724%) (p<0.02 in SNU-C4 and p<0.1in SNU-C5 at the 13th day after injection of antibodies). On the thirteenth day after injection of the antibodies nude mice were sacreficed to count the radiouptake of tumor and to check the changes of tumor size. Correlations between radiouptake and change of tumor size were calculated in each groups and significant negative correlation was only obtained in the group treated with I-131 anti-CEA antibody (p<0.05). There were no correlations between antigenic expression of carcinoembryonic antigen and

BRCAA1 antibody- and Her2 antibody-conjugated amphiphilic polymer engineered CdSe/ZnS quantum dots for targeted imaging of gastric cancer

Science.gov (United States)

Li, Chao; Ji, Yang; Wang, Can; Liang, Shujing; Pan, Fei; Zhang, Chunlei; Chen, Feng; Fu, Hualin; Wang, Kan; Cui, Daxiang

2014-05-01

Successful development of safe and highly effective nanoprobes for targeted imaging of in vivo early gastric cancer is a great challenge. Herein, we choose the CdSe/ZnS (core-shell) quantum dots (QDs) as prototypical materials, synthesized one kind of a new amphiphilic polymer including dentate-like alkyl chains and multiple carboxyl groups, and then used the prepared amphiphilic polymer to modify QDs. The resultant amphiphilic polymer engineered QDs (PQDs) were conjugated with BRCAA1 and Her2 monoclonal antibody, and prepared BRCAA1 antibody- and Her2 antibody-conjugated QDs were used for in vitro MGC803 cell labeling and in vivo targeted imaging of gastric cancer cells. Results showed that the PQDs exhibited good water solubility, strong photoluminescence (PL) intensity, and good biocompatibility. BRCAA1 antibody- and Her2 antibody-conjugated QD nanoprobes successfully realized targeted imaging of in vivo gastric cancer MGC803 cells. In conclusion, BRCAA1 antibody- and Her2 antibody-conjugated PQDs have great potential in applications such as single cell labeling and in vivo tracking, and targeted imaging and therapeutic effects' evaluation of in vivo early gastric cancer cells in the near future.

Technetium-99m pertechnetate - a tracer for radiolabelling antibody for inflammation detection

International Nuclear Information System (INIS)

Shaharuddin Mohd; Wan Hamirul Bahrin Wan Kamal; Shahrin A Hamid; Ang Woan Tze; Rosnani Hashim

1999-01-01

The polyclonal antibody, Human Immunoglobulin G (HlgG) was reduced by using 2-mercaptoethanol with molar ratio of 1000:1 (i.e. mercaptoethanol:antibody). The reduction of the antibody, was carried out for 30 minutes at room temperature. The reduced antibody was purified by using Sephadex G-25 fine column. The antibody kit for the detection of inflammation was prepared aseptically in Class 1 Laminar Flow cabinet. The kit passed the sterility test. Upon reconstitution of the antibody kit with sodium pertechnetate-99m ( 99m Tc) solution, the labelling efficiency obtained was more than 95%. This preparation was stable up to 24-hour stored at room temperature. Gamma camera scans showed the accumulation of technetium-99m labelled antibody ( 99m Tc-HIgG) at the turpentine-induced inflammation of female Sprague-Dawley rats. This indicated the possibility of using 99m Tc-HIgG for inflammation detection. (author)

Hepatitis A virus antibody

International Nuclear Information System (INIS)

Novak, J.; Kselikova, M.; Urbankova, J.

1980-01-01

A description is presented of a radioimmunoassay designed to prove the presence of the antibody against the hepatitis A virus (HA Ab, anti-Ha) using an Abbott HAVAB set. This proof as well as the proof of the antibody against the nucleus of the hepatitis B virus is based on competition between a normal antibody against hepatitis A virus and a 125 I-labelled antibody for the binding sites of a specific antigen spread all over the surface of a tiny ball; this is then indirect proof of the antibody under investigation. The method is described of reading the results from the number of impulses per 60 seconds: the higher the titre of the antibody against the hepatitis A virus in the serum examined, the lower the activity of the specimen concerned. The rate is reported of incidence of the antibody against the hepatitis A virus in a total of 68 convalescents after hepatitis A; the antibody was found in 94.1%. The immunoglobulin made from the convalescents' plasma showed the presence of antibodies in dilutions as high as 1:250 000 while the comparable ratio for normal immunoglobulin Norga was only 1:2500. Differences are discussed in the time incidence of the antibodies against the hepatitis A virus, the antibodies against the surface antigen of hepatitis B, and the antibody against the nucleus of the hepatitis V virus. (author)

Clinical experience in humans with radiolabeled antibody for tumor detection

International Nuclear Information System (INIS)

Morrison, R.T.; Lyster, D.M.; Szasz, I.; Alcorn, L.N.; Huckell, V.F.; Rhodes, B.; Breslow, K.; Burchiel, S.

1982-01-01

I-131 and Tc-99m labeled polyclonal or monoclonal antibody and fragments of antibody, specific to human chorionic gonadotropin (hCG) or to a melanoma cell surface antigen (MCSA) were injected into proven cancer patients. Using standard homeostasis parameters, and scanning techniques, the safety and efficacy of each antibody was evaluated. Antibody fragments were expected to clear faster from the circulation allowing for earlier imaging and a better target-to-non-target ratio. The technetium label may perturb the antiboby's kinetics so that clearance is more rapid for both whole antibody and fragments. After a statistical evaluation of all parameters measured pre and post injection it was concluded that no acute toxicity reactions were present in any patient studied. Scan results were not acceptable for a tumor detecting procedure used in routine practice. Tumor upake was seen in less than 10% of scans

C-kit-targeted imaging of gastrointestinal stromal tumor using radiolabeled anti-c-kit monoclonal antibody in a mouse tumor model

International Nuclear Information System (INIS)

Sogawa, Chizuru; Tsuji, Atsushi B.; Sudo, Hitomi; Sugyo, Aya; Yoshida, Chisato; Odaka, Kenichi; Uehara, Tomoya; Arano, Yasushi; Koizumi, Mitsuru; Saga, Tsuneo

2010-01-01

Introduction: Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor arising from the gastrointestinal tract and highly expresses mutated c-kit. We aimed to develop a specific and sensitive method for detecting GISTs using radiolabeled anti-c-kit monoclonal antibody. Methods: A mutated c-kit-expressing cell clone was established by transfecting an expressing vector of mutated c-kit gene into HEK293 human embryonic kidney cells. The tumors were developed by inoculating c-kit-expressing cells into nude mice. 125 I- and 111 In-labeled anti-c-kit antibodies (12A8 and 41A11) were evaluated in vitro by cell binding, competitive inhibition and cellular internalization assays, and in vivo by biodistribution and imaging studies in tumor-bearing mice. Results: Both 125 I- and 111 In-labeled antibodies showed specific binding with c-kit-expressing cells with high affinity (dissociation constants = 2.2-7.1x10 9 M -1 ). Internalization assay showed that 125 I-labeled antibodies were rapidly internalized and dehalogenated, with the release of 125 I from the cells, resulting in reduction of cell-associated radioactivity with time. In contrast, 111 In-labeled antibody was internalized but did not result in the reduced radioactivity associated with tumor cells. Reflecting this phenomenon, the in vivo tumor uptake of 125 I-labeled antibody was low on Day 1, further decreasing with time, while tumor uptake of 111 In-labeled antibody was high on Day 1, further increasing with time. The xenografted tumor was clearly visualized by scintigraphy after injection of 111 In-labeled antibody. Conclusion: The anti-c-kit monoclonal antibody labeled with a metal radionuclide would be promising for c-kit-targeted imaging of GISTs.

Immunoscintigraphy of metastases with radiolabelled human antibodies

Energy Technology Data Exchange (ETDEWEB)

Al-Azzawi, F.; Smith, J.; Stimson, W.H.

1987-02-28

It was concluded that Epstein-Barr virus transformation of committed lymphocytes offers great potential in the production of antitumour antibodies of human origin. An outline case report is presented where the human I/sup 131/ labelled antibody was used as a targeting agent to delineate the extent of secondary growth in the liver. (U.K.).

[Neuroimmunological diseases associated with VGKC complex antibodies].

Science.gov (United States)

Watanabe, Osamu

2013-05-01

Antibodies to voltage-gated potassium channels(VGKC) were first identified by radioimmunoassay of radioisotope labeled alpha-dendrotoxin-VGKCs solubilized from rabbit brain. These antibodies were found only in a proportion of patients with acquired neuromyotonia (Isaacs' syndrome). VGKC antibodies were also detected in Morvan's syndrome and in a form of autoimmune limbic encephalitis. Recent studies indicated that the "VGKC" antibodies are mainly directed toward associated proteins(for example LGI-1, Caspr-2) that complex with the VGKCs themselves. The "VGKC" antibodies are now usually known as VGKC-complex antibodies. In general, LGI-1 antibodies are most common in limbic encephalitis with SIADH. Caspr-2 antibodies are present in the majority of patients with Morvan's syndrome. These patients develop combinations of CNS symptoms, autonomic dysfunction, and peripheral nerve hyperexcitability.

Use of commercially available rabbit monoclonal antibodies for immunofluorescence double staining

DEFF Research Database (Denmark)

Bzorek, M.; Stamp, I.M.; Frederiksen, L.

2008-01-01

Immunohistochemistry, that is, the use of polyclonal and monoclonal antibodies to detect cell and tissue antigens at a microscopical level is a powerful tool for both research and diagnostic purposes. Especially in the field of hematologic disease, there is often a need to detect several antigens...... synchronously, and we report here a fast and easy technique for demonstrating more than 1 antigen in 1 slide using immunofluorescence. We have used commercially available rabbit monoclonal antibodies (Cyclin D1, CD3, CD5, CD23, etc.) paired with mouse monoclonal antibodies (CD7, CD20, CD79a, Pax-5, etc.......) for double immunofluorescence labeling on paraffin-embedded tissue sections. Commercially available rabbit monoclonal antibodies in combination with mouse monoclonal antibodies proved useful in double immunofluorescence labeling on paraffin-embedded tissue, and all combinations used yielded excellent results...

Utilisation of tracer monoclonal antibodies for the immunoscintigraphic detection of human colorectal cancers

International Nuclear Information System (INIS)

Chatal, J.F.; Douillard, J.Y.; Kremer, M.; Curtet, C.; Le Mevel, B.; Fumoleau, P.; Bourdoiseau, M.

1983-01-01

Two monoclonal antibodies, 17-1A and 19-9, with recognized human gastrointestinal cancers in cell cultures, were labeled with iodine 131 for immunoscintigraphic application. With the intact 131 I-17-1A antibody, 21 out of 35 (60%) primary or secondary colorectal cancer sites were visualized, whereas all 21 nonepitheliomatous colic cancer sites or noncolic cancer sites were negative. With F(ab') 2 fragments of the 19-9 antibody, 18 out of 27 (67%) colorectal cancer sites were positive. With both radioantibodies, the bestly contrasted tumor images were late, 4 to 5 days after injection. A study with paired-label technique, associating a specific iodine-131-labeled antibody with a non-specific iodine-125-labeled immunoglobulin, demonstrated, that tumor uptake was indeed specific for the 17-1A or 19-9 antibody in tumor and normal colon fragments obtained during operations on 4 patients. A preliminary prospective study showed that only immunoscintigraphy was able to confirm and localize a recurrence of rectal cancer in one patient. A larger series will be necessary to validate the clinical benefit of the technique, as compared with the results of other diagnostic techniques, before immunoscintigraphy can be proposed for routine clinical use [fr

Monoclonal antibodies in oncology

International Nuclear Information System (INIS)

Chan, S.Y.T.; Sikora, K.

1986-01-01

Monoclonal antibodies (MCAs) can be used to differentiate between normal and neoplastic cells and thus exploited for diagnostic and, ultimately, therapeutic gain. The evidence for the existence of human tumour antigens is reviewed. Several areas of diagnosis are already benefiting from the application of the monoclonal technology. Immunohistology can help the pathologist with difficult diagnostic problems. New classifications of lymphoma and leukaemia can be based on specific surface molecules. Similarly, the detection of shed tumour antigens is already established as part of the routine assessment of many patients with common solid tumours. Isotopically labeled monoclonal antibodies have been used to localise primary and metastatic tumours. The use of antibodies in this way is not only a promising diagnostic tool but also the first step in studying the possibility of arming antibodies to provide therapeutic agents. Such trials are currently in progress. (Auth.)

Digoxigenylated wheat germ agglutinin visualized with alkaline phosphatase-labeled anti-digoxigenin antibodies--a new, sensitive technique with the potential for single and double tracing of neuronal connections.

Science.gov (United States)

Veh, R W

1991-01-02

For double tracing experiments, wheat germ agglutinin (WGA) molecules labeled with two different haptens are desirable. In the present report the suitability of digoxigenylated WGA (DIG-WGA) for retrograde tracing was investigated. For this purpose the new tracer was pressure injected into rat brains and the transported DIG-WGA visualized via its digoxigenyl group with an alkaline phosphatase linked anti DIG antibody in permanently stained sections of high quality. With fixatives containing 2.5% glutaraldehyde only few positive cells were found. However, at milder fixation conditions (4% paraformaldehyde, 0.05% glutaraldehyde 0.2% picric acid, 30 min) retrogradely labeled cells were detected with a sensitivity comparable to tetramethylbenzidine protocols for conventional WGA-HRP (horseradish peroxidase) tracing. Preliminary experiments suggest excellent suitability for double labeling.

Labeling of human immune gamma globulin with sup(99m)Tc

International Nuclear Information System (INIS)

Wong, D.W.; Huang, J.T.

1977-01-01

Human immune serum gamma globulin and rabbit anti-Stap. aureus antibody have been successfully labeled with sup(99m)Tc at pH 7.4 with an average binding efficiency of 86 and 82%, respectively. The labeled proteins behave similarly to unlabeled gamma-globulin fraction in the normal human serum as demonstrated by protein electrophoresis. The biological half-time of sup(99m)Tc-gamma-globulin in dog has been determined to be 54 min for the fast component and 14.7 hr for a slower component. Immunological assays demonstrate no significant change in antibody activity after labeling process. (author)

An optimized antibody-chelator conjugate for imaging of carcinoembryonic antigen with indium-111

International Nuclear Information System (INIS)

Sumerdon, G.A.; Rogers, P.E.; Lombardo, C.M.; Schnobrich, K.E.; Melvin, S.L.; Tribby, I.I.E.; Stroupe, S.D.; Johnson, D.K.; Hobart, E.D.

1990-01-01

A monoclonal antibody to carcinoembryonic antigen showing minimal cross-reactivity with blood cells and normal tissues was derivatized with benzylisothiocyanate derivatives of EDTA and DTPA. Seven chelators per immunoglobulin could be incorporated without loss of immunoreactivity. The resulting conjugates, labeled with indium-111, showed low liver uptake in animals. A cold kit, comprising the DTPA conjugate at a molarity of antibody bound chelator exceeding 1 x 10 -4 M, gave radiochemical yields of indium labeled antibody of ≥ 95% and was stable for 1 yr. (author)

Transient human anti-mouse antibodies (HAMA) interference in CA 125 measurements during monitoring of ovarian cancer patients treated with murine monoclonal antibody.

NARCIS (Netherlands)

Oei, A.L.M.; Sweep, F.C.; Massuger, L.F.A.G.; Olthaar, A.J.; Thomas, C.M.G.

2008-01-01

OBJECTIVE: To investigate the influence of human anti-mouse antibodies (HAMA) on serial CA 125 measurements in serum of patients with epithelial ovarian cancer following single intraperitoneal (IP) therapy with Yttrium-90-labeled human milk fat globule 1 murine monoclonal antibody ((90)Y-muHMFG1) as

Development of labelled biomolecules for targeted radiotherapy. Mexico

International Nuclear Information System (INIS)

Arteaga de Murphy, Consuelo

2000-01-01

The scope of the co-ordinated research project (Dec 15 1997) included the following activities: 1) develop coupling techniques using bifunctional chelating agents for monoclonal antibodies and peptides; 2) optimise radiolabelling procedures and reaction parameters using Sm-153 and Re-188; 3) investigate direct methods of labelling monoclonal antibodies and peptides with Re-188; 4) initiate animal distribution studies. The modifications specified for the period 1999/02/15 to 2000/02/14 are as follows: a) continue with the optimisation of Re-188-peptide labelling; b) continue with the work to prepare a kit; c) in-vivo and in-vitro studies; d) Lanreotide labelling. The group formed by researchers from several Mexican institutions have worked together and in different aspects of the CRP in order to fulfil the proposed aims

Specificity of anti-tau antibodies when analyzing mice models of Alzheimer's disease: problems and solutions.

Directory of Open Access Journals (Sweden)

Franck R Petry

Full Text Available Aggregates of hyperphosphorylated tau protein are found in a group of diseases called tauopathies, which includes Alzheimer's disease. The causes and consequences of tau hyperphosphorylation are routinely investigated in laboratory animals. Mice are the models of choice as they are easily amenable to transgenic technology; consequently, their tau phosphorylation levels are frequently monitored by Western blotting using a panel of monoclonal/polyclonal anti-tau antibodies. Given that mouse secondary antibodies can recognize endogenous mouse immunoglobulins (Igs and the possible lack of specificity with some polyclonal antibodies, non-specific signals are commonly observed. Here, we characterized the profiles of commonly used anti-tau antibodies in four different mouse models: non-transgenic mice, tau knock-out (TKO mice, 3xTg-AD mice, and hypothermic mice, the latter a positive control for tau hyperphosphorylation. We identified 3 tau monoclonal antibody categories: type 1, characterized by high non-specificity (AT8, AT180, MC1, MC6, TG-3, type 2, demonstrating low non-specificity (AT270, CP13, CP27, Tau12, TG5, and type 3, with no non-specific signal (DA9, PHF-1, Tau1, Tau46. For polyclonal anti-tau antibodies, some displayed non-specificity (pS262, pS409 while others did not (pS199, pT205, pS396, pS404, pS422, A0024. With monoclonal antibodies, most of the interfering signal was due to endogenous Igs and could be eliminated by different techniques: i using secondary antibodies designed to bind only non-denatured Igs, ii preparation of a heat-stable fraction, iii clearing Igs from the homogenates, and iv using secondary antibodies that only bind the light chain of Igs. All of these techniques removed the non-specific signal; however, the first and the last methods were easier and more reliable. Overall, our study demonstrates a high risk of artefactual signal when performing Western blotting with routinely used anti-tau antibodies, and proposes

Preparation and Evaluation of 99mTc-labeled anti-CD11b Antibody Targeting Inflammatory Microenvironment for Colon Cancer Imaging.

Science.gov (United States)

Cheng, Dengfeng; Zou, Weihong; Li, Xiao; Xiu, Yan; Tan, Hui; Shi, Hongcheng; Yang, Xiangdong

2015-06-01

CD11b, an active constituent of innate immune response highly expressed in myeloid-derived suppressor cells (MDSCs), can be used as a marker of inflammatory microenvironment, particularly in tumor tissues. In this research, we aimed to fabricate a (99m)Tc-labeled anti-CD11b antibody as a probe for CD11b(+) myeloid cells in colon cancer imaging with single-photon emission computed tomography (SPECT). In situ murine colon tumor model was established in histidine decarboxylase knockout (Hdc(-/-)) mice by chemicals induction. (99m)Tc-labeled anti-CD11b was obtained with labeling yields of over 30% and radiochemical purity of over 95%. Micro-SPECT/CT scans were performed at 6 h post injection to investigate biodistributions and targeting of the probe. In situ colonic neoplasma as small as 3 mm diameters was clearly identified by imaging; after dissection of the animal, anti-CD11b immunofluorescence staining was performed to identify infiltration of CD11b+ MDSCs in microenvironment of colonic neoplasms. In addition, the images displayed intense signal from bone marrow and spleen, which indicated the origin and migration of CD11b(+) MDSCs in vivo, and these results were further proved by flow cytometry analysis. Therefore, (99m)Tc-labeled anti-CD11b SPECT displayed the potential to facilitate the diagnosis of colon tumor in very early stage via detection of inflammatory microenvironment. © 2014 John Wiley & Sons A/S.

Tumor imaging with monoclonal antibodies

International Nuclear Information System (INIS)

Haisma, H.; Hilgers, J.

1987-01-01

Many monoclonal antibodies directed against tumor-associated antigens have been identified, but so far none of these are tumor specific. Polyclonal and monoclonal antibodies have been used for imaging of a wide variety of tumors with success. Radiolabeling of antibody is usually done with iodine isotopes of which 123 I is the best candidate for radioimmunodetection purposes. The labeling of antibodies through chelates makes it possible to use metal radioisotopes like 111 In, which is the best radioisotope for imaging with monoclonal antibodies due to its favorable half-life of 2.5 days. Usually imaging cannot be performed within 24 h after injection, but clearance of antibody can be increased by using F(ab) 2 of Fab. Another approach is to clear non-bound antibody by a second antibody, directed against the first. The detection limit of immunoimaging is about 2 cm, but will be improved by tomography or SPECT. There is still a high false positive and false negative rate, which makes it impossible to use radioimmunodetection as the only technique for diagnosis of tumors. In combination with other detection techniques, tumor imaging with monoclonal antibodies can improve diagnosis. 44 refs.; 3 tabs

Assay for the specificity of monoclonal antibodies in crossed immunoelectrophoresis

DEFF Research Database (Denmark)

Skjødt, K; Schou, C; Koch, C

1984-01-01

A method is described based on crossed immunoelectrophoresis of a complex antigen mixture in agarose gel followed by incubation of the gel with the monoclonal antibody. The bound monoclonal antibody is detected by the use of a secondary enzyme-labelled antibody. Using this technique we have been ...... I molecules. In other experiments using the same technique we demonstrated the reaction of a monoclonal antibody specific for chicken Ig light chains. Udgivelsesdato: 1984-Aug-3...

The preparation and use of radiolabelled specific helminth antibodies

International Nuclear Information System (INIS)

Movsesijan, M.; Jovanovic, B.; Borojevic, D.; Petrovic, M.

1983-01-01

Specific antibodies from the serum of sheep infected with Haemonchus contortus were isolated by combination with a ''solid phase antigen'' (soluble antigen coupled to an activated crystalline cellulose). The antibodies were labelled with 125 I while bound to the solid phase then eluted and their potential demonstrated: (1) to determine amounts of specific antibody in unknown sera; (2) to determine amounts of soluble antigen in unknown preparations. (author)

The influence of proteasome inhibitor MG132, external radiation and unlabeled antibody on the tumor uptake and biodistribution of 188Re-labeled anti-E6 C1P5 antibody in cervical cancer in mice

Science.gov (United States)

Phaeton, Rébécca; Wang, Xing Guo; Einstein, Mark H.; Goldberg, Gary L.; Casadevall, Arturo; Dadachova, Ekaterina

2009-01-01

Background Human Papillomavirus (HPV) infection is considered a necessary step for the development of cervical cancer and >95% of all cervical cancers have detectable HPV sequences. We have recently demonstrated the efficacy of radioimmunotherapy (RIT) which targeted viral oncoprotein E6 in treatment of experimental cervical cancer We hypothesized that pre-treatment of tumor cells with various agents which cause cell death and/or elevation of E6 levels would increase the accumulation of radiolabeled antibodies to E6 in cervical tumors. Methods HPV-16 positive CasKi cells were treated in vitro with up to 6 Gy of external radiation, or proteasome inhibitor MG-132 or unlabeled anti-E6 antibody C1P5 and cell death was assessed. Biodistribution of 188Rhenium (188Re)-labeled C1P5 antibody was performed in both control and radiation MG-132 treated CasKi tumor-bearing nude mice. Results . 188Re-C1P5 antibody demonstrated tumor specificity and very low uptake and fast clearance from the major organs. The amount of tumor uptake was enhanced by MG-132 but was unaffected by pre-treatment with radiation. In addition, in vitro studies demonstrated an unanticipated effect of unlabeled antibody on the amount of cell death, a finding that was suggested by our previous in vivo studies in CasKi tumor model. Conclusion We demonstrated that pre-treatment of cervical tumors with proteasome inhibitor MG-132 and with unlabeled antibody to E6 can serve as a means to generate non-viable cancer cells and to elevate the levels of target oncoproteins in the cells for increasing the accumulation of targeted radiolabeled antibodies in tumors. These results favor further development of RIT of cervical cancers targeting viral antigens. PMID:20127955

Radioimmunodetection of hepatocellular carcinoma with a radiolabeled antibody to alpha fetoprotein

Energy Technology Data Exchange (ETDEWEB)

Ishii, N; Nakata, K; Muro, T [Nagasaki Univ. (Japan). School of Medicine

1982-03-01

The present study was undertaken to investigate whether or not radiolabeled antibody to Alpha-fetoprotein (AFP) intravenously administered accumulates in AFP-producing tumors. Rats with subcutaneously transplanted hepatoma or with heptoma produced in liver by 3'-Me-DAB, and 12 patients with hepatocellular carcinoma (HCC) were studied. In animal experiments, the tumor localization was clearly demonstrated by total body scintigraphy 48 to 168 hours after the injection of the radioiodinated antibody. The rats were sacrificed and radioactivity in tissues was counted. Tumor tissues showed the highest counts. In patients with HCC, the imaging was made with a gamma camera usually 24 and 48 hours after injection of I-131-labeled antibody. In order to make the contrast of tumor image clear, nonspecific background images obtained by administration of Tc-99m-labeled serum albumin were subtracted from the images obtained by I-131 labeled antibody with a computer. In 6 of 12 patients with HCC, the tumor location could successfully demonstrated. However, tumor with sizes below 2 cm in diameter which were able to be detected by the celiac angiography were not detectable. Interestingly the images were more clear in patients with relatively higher serum AFP levels. In the blood of patient given injection of AFP radioantibody, both immune complex and free antibody were able to be detected at least for 120 hours so that the presence of free antigen (AFP) did not appear to prevent tumor radioimmunodetection. The information obtained concerning the biochemical factors which influence antibody localization in the tumor would provide better method for radioimmunodetection with antitumor antibodies.

Estimation of antibodies to human cytomegalovirus by immunofluorescence and radioimmunoassay

International Nuclear Information System (INIS)

Jankowski, M.; Gut, W.; Nawrocka, E.

1980-01-01

The 125 I labelled IgG fraction against rabbit IgG of goat origin was employed for the detection of CMV IgG and IgM antibodies in the double indirect radioimmunoassay. The results were compared with those obtained in complement fixation, indirect immunofluorescence and anti-complement immunofluorescence tests. The application of labelled anti-fc antisera, instead of antisera against whole IgG in the tests for detection of specific CMV IgG antibody resulted in increased sensitivity of radioimmunoassay and reduction of non-specific cytoplasmatic reactions in preparations stained by indirect immunofluorescence. The absorption of sera with protein A rich staphylococci and aggregates to immunoglobulin eliminated unwanted secondary IgM staining caused by rheumatoid factors both in indirect immunofluorescence and radioimmunoassay tests for CMV antibodies. (author)

New Insights into the Functional Behavior of Antibodies as Revealed by Binding Studies on an Anti-Uranium Monoclonal Antibody

International Nuclear Information System (INIS)

Blake, Diane A.; Xia Li; Haini Yu; Blake, Robert C.

2004-01-01

As part of an ongoing effort to develop immunoassays for chelated uranium(VI) on a hand-held flow fluorimeter, an anti-uranium monoclonal antibody designated as 8A11 was fluorescently labeled using two different strategies. When 8A11 was coupled via reactive lysines to either ALEXATM 488 or Cy5TM, the resulting fluorescent antibody conjugate exhibited positive cooperativity in the presence of its antigen, U(VI) chelated with 2,9-dicarboxy-1,10-phenanthroline (U(VI)-DCP). That is, when one of the two binding sites on the covalently modified 8A11 was occupied with bound antigen, the affinity of the remaining site on the antibody for U(VI)-DCP appeared to increase. Unmodified 8A11 bound U(VI)-DCP with the expected hyperbolic dependence on the concentration of antigen, consistent with independent and equal binding of ligand at both sites. Proteolytic cleavage of the fluorescently conjugated 8A11 to produce the fluorescent monovalent Fab fragment yielded an active preparation that now bound U(VI)-DCP with no evidence of positive cooperativity. Although, in principle, any divalent antibody has the potential to exhibit positive cooperativity in its binding interactions with its antigen, very little literature precedent for this type of behavior exists. Native 8A11 was also noncovalently labeled with highly fluorescent ZENONTM reagents. These reagents are fluorescently-labeled Fab fragments of goat anti-mouse antibodies that bind to the Fc portion of 8A11. These high-affinity, monovalent fluorescent reagents permitted the intact 8A11 mouse antibody to be labeled in situ with no covalent modifications. Incubation of the 8A11 with ZENON 647 produced a fluorescent protein complex that showed an 8-fold higher affinity for U(VI)-DCP than did the free 8A11 alone. Again, very few literature precedents exist for this phenomenon, where agents that bind to the Fc portion of an intact antibody change the affinity of the antibody for the antigen at the structurally distant Fab portion

A Real-Time Near-Infrared Fluorescence Imaging Method for the Detection of Oral Cancers in Mice Using an Indocyanine Green-Labeled Podoplanin Antibody.

Science.gov (United States)

Ito, Akihiro; Ohta, Mitsuhiko; Kato, Yukinari; Inada, Shunko; Kato, Toshio; Nakata, Susumu; Yatabe, Yasushi; Goto, Mitsuo; Kaneda, Norio; Kurita, Kenichi; Nakanishi, Hayao; Yoshida, Kenji

2018-01-01

Podoplanin is distinctively overexpressed in oral squamous cell carcinoma than oral benign neoplasms and plays a crucial role in the pathogenesis and metastasis of oral squamous cell carcinoma but its diagnostic application is quite limited. Here, we report a new near-infrared fluorescence imaging method using an indocyanine green (ICG)-labeled anti-podoplanin antibody and a desktop/a handheld ICG detection device for the visualization of oral squamous cell carcinoma-xenografted tumors in nude mice. Both near-infrared imaging methods using a desktop (in vivo imaging system: IVIS) and a handheld device (photodynamic eye: PDE) successfully detected oral squamous cell carcinoma tumors in nude mice in a podoplanin expression-dependent manner with comparable sensitivity. Of these 2 devices, only near-infrared imaging methods using a handheld device visualized oral squamous cell carcinoma xenografts in mice in real time. Furthermore, near-infrared imaging methods using the handheld device (PDE) could detect smaller podoplanin-positive oral squamous cell carcinoma tumors than a non-near-infrared, autofluorescence-based imaging method. Based on these results, a near-infrared imaging method using an ICG-labeled anti-podoplanin antibody and a handheld detection device (PDE) allows the sensitive, semiquantitative, and real-time imaging of oral squamous cell carcinoma tumors and therefore represents a useful tool for the detection and subsequent monitoring of malignant oral neoplasms in both preclinical and some clinical settings.

Preclinical evaluation of (111)In-DTPA-INCA-X anti-Ku70/Ku80 monoclonal antibody in prostate cancer.

Science.gov (United States)

Evans-Axelsson, Susan; Vilhelmsson Timmermand, Oskar; Welinder, Charlotte; Borrebaeck, Carl Ak; Strand, Sven-Erik; Tran, Thuy A; Jansson, Bo; Bjartell, Anders

2014-01-01

The aim of this investigation was to assess the Ku70/Ku80 complex as a potential target for antibody imaging of prostate cancer. We evaluated the in vivo and ex vivo tumor targeting and biodistribution of the (111)In-labeled human internalizing antibody, INCA-X ((111)In-DTPA-INCA-X antibody), in NMRI-nude mice bearing human PC-3, PC-3M-Lu2 or DU145 xenografts. DTPA-conjugated, non-labeled antibody was pre-administered at different time-points followed by a single intravenous injection of (111)In-DTPA-INCA-X. At 48, 72 and 96 h post-injection, tissues were harvested, and the antibody distribution was determined by measuring radioactivity. Preclinical SPECT/CT imaging of mice with and without the predose was performed at 48 hours post-injection of labeled DTPA-INCA-X. Biodistribution of the labeled antibody showed enriched activity in tumor, spleen and liver. Animals pre-administered with DTPA-INCA-X showed increased tumor uptake and blood content of (111)In-DTPA-INCA-X with reduced splenic and liver uptake. The in vitro and in vivo data presented show that the (111)In-labeled INCA-X antibody is internalized into prostate cancer cells and by pre-administering non-labeled DTPA-INCA-X, we were able to significantly reduce the off target binding and increase the (111)In-DTPA-INCA-X mAb uptake in PC-3, PC-3M-Lu2 and DU145 xenografts. The results are encouraging and identifying the Ku70/Ku80 antigen as a target is worth further investigation for functional imaging of prostate cancer.

Preclinical evaluation of 111In-DTPA-INCA-X anti-Ku70/Ku80 monoclonal antibody in prostate cancer

Science.gov (United States)

Evans-Axelsson, Susan; Vilhelmsson Timmermand, Oskar; Welinder, Charlotte; Borrebaeck, Carl AK; Strand, Sven-Erik; Tran, Thuy A; Jansson, Bo; Bjartell, Anders

2014-01-01

The aim of this investigation was to assess the Ku70/Ku80 complex as a potential target for antibody imaging of prostate cancer. We evaluated the in vivo and ex vivo tumor targeting and biodistribution of the 111In-labeled human internalizing antibody, INCA-X (111In-DTPA-INCA-X antibody), in NMRI-nude mice bearing human PC-3, PC-3M-Lu2 or DU145 xenografts. DTPA-conjugated, non-labeled antibody was pre-administered at different time-points followed by a single intravenous injection of 111In-DTPA-INCA-X. At 48, 72 and 96 h post-injection, tissues were harvested, and the antibody distribution was determined by measuring radioactivity. Preclinical SPECT/CT imaging of mice with and without the predose was performed at 48 hours post-injection of labeled DTPA-INCA-X. Biodistribution of the labeled antibody showed enriched activity in tumor, spleen and liver. Animals pre-administered with DTPA-INCA-X showed increased tumor uptake and blood content of 111In-DTPA-INCA-X with reduced splenic and liver uptake. The in vitro and in vivo data presented show that the 111In-labeled INCA-X antibody is internalized into prostate cancer cells and by pre-administering non-labeled DTPA-INCA-X, we were able to significantly reduce the off target binding and increase the 111In-DTPA-INCA-X mAb uptake in PC-3, PC-3M-Lu2 and DU145 xenografts. The results are encouraging and identifying the Ku70/Ku80 antigen as a target is worth further investigation for functional imaging of prostate cancer. PMID:24982817

Radiobromination of monoclonal antibody using potassium [{sup 76}Br] (4 isothiocyanatobenzyl-ammonio)-bromo-decahydro-closo-dodecaborate (Bromo-DABI)

Energy Technology Data Exchange (ETDEWEB)

Bruskin, Alexander; Sivaev, Igor; Persson, Mikael; Lundqvist, Hans; Carlsson, Joergen; Sjoeberg, Stefan; Tolmachev, Vladimir E-mail: Vladimir.Tolmachev@bms.uu.se

2004-02-01

The use of charged linkers in attaching radiohalogens to tumor-seeking biomolecules may improve intracellular retention of the radioactive label after internalization and degradation of targeting proteins. Derivatives of polyhedral boron clusters, such as closo-dodecaborate (2-) anion, might be possible charged linkers. In this study, a bifunctional derivative of closo-dodecaborate, (4-isothiocyanatobenzyl-ammonio)-undecahydro-closo-dodecaborate (DABI) was labeled with positron-emitting nuclide {sup 76}Br (T = 16.2 h) and coupled to anti-HER2/neu humanized antibody Trastuzumab. The overall labeling yield at optimized conditions was 80.7 {+-} 0.6%. The label was proven to be stable in vitro in physiological and a set of denaturing conditions. The labeled antibody retained its capacity to bind to HER-2/neu antigen expressing cells. The results of the study demonstrated feasibility for using derivatives of closo-dodecaborate in indirect labeling of antibodies for radioimmunoPET.

In Vitro Immunologic Studies with an {sup 131}I-Labelled Component of Complement

Energy Technology Data Exchange (ETDEWEB)

Spar, I. L.; Benz, L. L. [Department of Radiation Biology and Biophysics, University of Rochester School of Medicine and Dentistry, Rochester, NY (United States)

1970-02-15

Most of the in vitro immunological studies using radioactive isotopes have involved labelling of the reacting antigen or antibody. For meaningful results, it is also necessary to use a relatively purified preparation of either the antigen or antibody. This has been difficult to obtain when the antigenic component is ill- defined, as in tissue or tumour immunity. It seemed possible that detection of reactions of this type could be done more easily by using labelled components of haemolytic complement, since some of the factors involved in this 9-11 factor system are known to firmly bind to most antigen-antibody combinations. As an initial step in this study, {sup 125}I- or {sup 131}I-labelled components of complement were used to detect and quantitate known antigen-antibody systems. The initial reacting component of guinea pig complement, C'l, was partially purified and labelled with {sup 125}I or {sup 131}I. It was found that labelled C'l would react with ovalbumin- antiovalbumin (OA) precipitates and would bind to sensitized sheep cells (EA) in proportion to the amount of haemolysin bound to the cells. EDTA elusion of such bound {sup 125}I-C'l yielded a product that would react with EA or OA to a much greater extent than the starting material. In addition, lysis of EA would occur after binding of eluted {sup 125}I-C'l if the remaining complement components were added to the system. In further studies it was found that {sup 131}I-C'l could be used to detect reactions between anti-kidney antisera and hpmogenates of kidney, liver and lung. Extension of this work with isotopically labelled components of complement to a study involving tissue sections after incubation with antisera could lead to defection of tissue-antitissue antibody binding in situ. By utilizing autoradiographic techniques, one can further extend this system to define the site of antibody fixation. A distinct advantage of this approach is that the isotopically labelled reactant, complement, is

Development of radioactively labelled cancer seeking biomolecules for targeted radiotherapy

International Nuclear Information System (INIS)

Varvarigou, A.D.; Archimandritis, S.C.

2000-01-01

Within the framework of the above project we are studying the labelling of biomolecules, peptides and antibodies, with radionuclides emitting β - and γ radiation. More specifically, for the time being, we have investigated the labelling of peptides with Re-188 and of antibodies with Sm-153 and Re-188. The radiolabelled derivatives are further evaluated in vivo for possible application in Oncology. For these radiobiological studies we are trying to apply ectopic and orthotopic tumour animal models and to develop, in collaboration with other national and foreign institutes, proper imaging devices for small animal imaging

Pharmacokinetics, biodistribution and dosimetry of 99mTc-labeled anti-human epidermal growth factor receptor humanized monoclonal antibody R3 in rats

International Nuclear Information System (INIS)

Escobar, Normando Iznaga; Morales, Alejo Morales; Duconge, Jorge; Torres, Idania Caballero; Fernandez, Eduardo; Gomez, Jose A.

1998-01-01

The pharmacokinetics, biodistribution and dosimetry of 99m Tc-labeled anti-human epidermal growth factor receptor (anti-hEGF-r) humanized monoclonal antibody (MAb) R3 was investigated following intravenous injection in normal Wistar rats. Serum disappearance curves were best fit by a two-compartment model having a mean distribution half-life (t (1(2α)) ) of 0.250 h and a mean elimination (t (1(2β)) ) of 13.89 h. Among the various organs, a little accumulation of the radiolabeled antibody was found only in kidneys. Biodistribution and dosimetry studies in humans were performed by extrapolation of the animal data to humans. Absorbed dose to normal organs and the remainder of the whole body were estimated using the medical internal radiation dose formula, and dose contributions from radioactivity in transit through the gastrointestinal tract were estimated using a compartment model. Extrapolated values of radiation absorbed dose to normal organs in rads per millicurie administered were whole body, 0.0085; lower large intestine wall, 0.0898; small intestine, 0.0530; upper large intestine wall, 0.0731; and kidneys, 0.0455. The effective dose equivalent predicted was 0.0162 rem/mCi and the effective dose was found to be 0.015 rem/mCi. On the basis of the pharmacokinetics, biodistribution and internal radiation dosimetry information obtained in this study, a diagnostic phase I clinical trial with 99m Tc-labeled humanized MAb R3 conjugate in patients should be supported

Dual fluorescence labeling of surface-exposed and internal proteins in erythrocytes infected with the malaria parasite Plasmodium falciparum

DEFF Research Database (Denmark)

Bengtsson, Dominique C; Sowa, Kordai M P; Arnot, David E

2008-01-01

There is a need for improved methods for in situ localization of surface proteins on Plasmodium falciparum-infected erythrocytes to help understand how these antigens are trafficked to, and positioned within, the host cell membrane. This protocol for confocal immunofluorescence microscopy combines...... and permeabilization; indirect labeling of the internal antigen using a secondary antibody tagged with a spectrally distinct fluorescent dye; and detection of the differentially labeled antigens using a laser scanning confocal microscope. The protocol can be completed in approximately 7 h. Although the protocol...... surface antigen labeling on live cells with subsequent fixation and permeabilization, which enables antibodies to penetrate the cell and label internal antigens. The key steps of the protocol are as follows: indirect labeling of the surface antigen using a fluorescently tagged secondary antibody; fixation...

A microfluidics-based technique for automated and rapid labeling of cells for flow cytometry

International Nuclear Information System (INIS)

Patibandla, Phani K; Estrada, Rosendo; Kannan, Manasaa; Sethu, Palaniappan

2014-01-01

Flow cytometry is a powerful technique capable of simultaneous multi-parametric analysis of heterogeneous cell populations for research and clinical applications. In recent years, the flow cytometer has been miniaturized and made portable for application in clinical- and resource-limited settings. The sample preparation procedure, i.e. labeling of cells with antibodies conjugated to fluorescent labels, is a time consuming (∼45 min) and labor-intensive procedure. Microfluidics provides enabling technologies to accomplish rapid and automated sample preparation. Using an integrated microfluidic device consisting of a labeling and washing module, we demonstrate a new protocol that can eliminate sample handling and accomplish sample and reagent metering, high-efficiency mixing, labeling and washing in rapid automated fashion. The labeling module consists of a long microfluidic channel with an integrated chaotic mixer. Samples and reagents are precisely metered into this device to accomplish rapid and high-efficiency mixing. The mixed sample and reagents are collected in a holding syringe and held for up to 8 min following which the mixture is introduced into an inertial washing module to obtain ‘analysis-ready’ samples. The washing module consists of a high aspect ratio channel capable of focusing cells to equilibrium positions close to the channel walls. By introducing the cells and labeling reagents in a narrow stream at the center of the channel flanked on both sides by a wash buffer, the elution of cells into the wash buffer away from the free unbound antibodies is accomplished. After initial calibration experiments to determine appropriate ‘holding time’ to allow antibody binding, both modules were used in conjunction to label MOLT-3 cells (T lymphoblast cell line) with three different antibodies simultaneously. Results confirm no significant difference in mean fluorescence intensity values for all three antibodies labels (p < 0.01) between the

Preparation, biodistribution and dosimetry of copper-64-labeled anti-colorectal carcinoma monoclonal antibody fragments 1A3-F(ab')2

International Nuclear Information System (INIS)

Anderson, C.J.; Schwarz, S.W.; Connett, J.M.

1995-01-01

Antibody fragments labeled with a radiometal using bifunctional chelates generally undergo renal clearance followed by trapping of the metabolites, leading to high radiation doses to the kidneys. Copper-64-labeled BAT-2IT-1A3-F(ab') 2 was recently reported to accumulate in colorectal tumors in an animal model, however, kidney uptake was also high. In this study, the preparation of 64 Cu-BAT-2IT-1A3-F(ab') 2 was optimized to reduce the renal uptake. The bifunctional chelate 6-bromoacetamidobenzyl-1,4,8,11-tetraazacyclotetradecane-N,N',N double-prime,N'double-prime-tetraacetic acid (BAT) was conjugated to 1A3-F(ab') 2 using the linking agent 2-iminothiolane (2IT). The conjugation reaction produced 20% of a lower molecular weight impurity found to be TETA-1A3-Fab'. The conjugation procedure was optimized to include FPLC purification of the BAT-2IT-1A3-F(ab') 2 from TETA-1A3-Fab' after conjugation prior to labeling with 64 Cu. The biodistribution of 64 Cu-labeled FPLC-purified and unpurified conjugates was determined in normal Sprague-Dawley rats and tumor-bearing Golden Syrian hamsters. Human absorbed doses were calculated from rat biodistribution data and PET imaging of a baboon. Upon FPLC purification of the BAT-2IT-1A3-F(ab') 2 , the immunoreactivity of 64 Cu-labeled 1A3-F(ab') 2 was significantly improved over that of non-FPLC-purified 64 Cu-BAT-2IT-1A3-F(ab') 2 , and the kidney uptake was decreased in normal rats. The biodistribution in hamsters showed some improvement in both tumor uptake and kidney clearance with FPLC-purified 64 Cu-BAT-2IT-1A3-F(ab') 2 .The improved dosimetry of 64 Cu-labeled FPLC purified BAT-2IT-1A3-F(ab') 2 should more readily allow this agent to be investigated clinically to image colorectal cancer using PET. 33 refs., 7 figs., 3 tabs

Tuning a Protein-Labeling Reaction to Achieve Highly Site Selective Lysine Conjugation.

Science.gov (United States)

Pham, Grace H; Ou, Weijia; Bursulaya, Badry; DiDonato, Michael; Herath, Ananda; Jin, Yunho; Hao, Xueshi; Loren, Jon; Spraggon, Glen; Brock, Ansgar; Uno, Tetsuo; Geierstanger, Bernhard H; Cellitti, Susan E

2018-04-16

Activated esters are widely used to label proteins at lysine side chains and N termini. These reagents are useful for labeling virtually any protein, but robust reactivity toward primary amines generally precludes site-selective modification. In a unique case, fluorophenyl esters are shown to preferentially label human kappa antibodies at a single lysine (Lys188) within the light-chain constant domain. Neighboring residues His189 and Asp151 contribute to the accelerated rate of labeling at Lys188 relative to the ≈40 other lysine sites. Enriched Lys188 labeling can be enhanced from 50-70 % to >95 % by any of these approaches: lowering reaction temperature, applying flow chemistry, or mutagenesis of specific residues in the surrounding protein environment. Our results demonstrated that activated esters with fluoro-substituted aromatic leaving groups, including a fluoronaphthyl ester, can be generally useful reagents for site-selective lysine labeling of antibodies and other immunoglobulin-type proteins. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Biodistribution of 99mTc-labeled anti-human epidermal growth factor receptor (EGF-R) humanized monoclonal antibody h-R3 in a xenograft model of human lung adenocarcinoma

International Nuclear Information System (INIS)

Morales-Morales, Alejo; Duconge, Jorge; Caballero-Torres, Idania; Nunez-Gandolff, Gilda; Fernandez, Eduardo; Iznaga-Escobar, Normando

1999-01-01

The anti-human epidermal growth factor receptor (EGF-R) humanized monoclonal antibody (MAb) h-R3 is an (IgG 1 ), which binds to an extracellular domain of EGF-R. It was used to evaluate the biodistribution on nude mice xenografted with H-125 human lung adenocarcinoma cell line. Results were compared with its murine version of the MAb ior-egf/r3. Twenty-one athymic female 4NMRI nu/nu mice were injected intraperitoneally with 10 μg/100 μCi of 99m Tc-labeled MAbs. Immunoreactivity of 99m Tc-labeled MAbs were measured by enzyme-linked immunosorbent assay (ELISA) on H-125 cell line and the immunoreactive fractions was determined by the Lindmo method. Among all organs, significant accumulation was found in serum (27.05 ± 2.08 %ID/g) and tumor (3.903 ± 0.89 %ID/g) at 4 h after injection. These values decreased to 5.03 ± 0.50 %ID/g and 2.19 ± 0.56 %ID/g for serum and tumor, respectively. The immunoreactive fraction was found to be 0.70, with a correlation coefficient r=0.9984. With the good biodistribution and tumor uptake of the 99m Tc-labeled humanized antibody h-R3, a phase I diagnostic clinical trial of tumor with epithelial origin should be pursued

Immunoscintigraphy of adenocarcinomas by means of 111In-labelled F(ab')2 fragments of anti-CEA monoclonal antibody F023C5

International Nuclear Information System (INIS)

Riva, P.; Paganelli, G.; Callegaro, L.

1988-01-01

F(ab') 2 fragments of F023C5, an anti-CEA monoclonal antibody, were conjugated to diethylenetriamine pentaacetic acid (DTPA) and converted into a ready to use reagent for instant 111 In-labelling. The resulting 111 In radiopharmaceutical was administered intravenously and tested for its ability to image (at 48-72 h after administration) 31 primary and 85 metastatic carcinoma lesions in 70 adenocarcinoma patients (26 gastrointestinal, 18 breast and 26 lung tumour patients) whose serum CEA was elevated in 43 cases and normal in the other 27. (author)

Sequential use of indium-111 labeled monoclonal antibodies 96.5 and ZME-018 does not increase detection sensitivity for metastatic melanoma

International Nuclear Information System (INIS)

Frontiera, M.; Murray, J.L.; Lamki, L.

1989-01-01

Two indium-111 labeled anti-melanoma murine monoclonal antibodies (MAb), 96.5 and ZME-018, each recognizing separate antigens on melanoma cells, were administered intravenously to 17 patients with melanoma in a sequential fashion to determine whether: (1) additional tumor sites could be imaged with the combination compared to a single Mab; (2) the first MAb influenced the biodistribution and tumor localization of the second; and (3) significantly toxicity occurred with the combination. Patients were randomized to receive either 96.5, followed by ZME-018, ZME-018 followed by 96.5, or each MAb followed by itself (controls). Infusions of the second MAb occurred 10 days after the first infusion. Gamma camera images were obtained 72 hours after each antibody infusion. There were 139 known metastatic sites of which 72 lesions were localized by either MAb for an overall sensitivity of 52%. The detection rate was higher when lesions only greater than 1.5 cm were considered. Imaging results were independent of MAb administration sequence. When ZME-018 was given as the first infusion, when ZME-018 was given as a second infusion (p = NS). However, mean sensitivities using 96.5 as the first or second infusion were 48% and 66% respectively (p = NS). There was not a significant number of sites detected by MAb 2 that were missed by MAb 1. Human anti-murine antibody (HAMA) response occurred in seven of eight patients studied; two patients who experienced toxicity had levels of HAMA greater than 2000 ng/ml. We conclude that the use of these two murine anti-melanoma monoclonal antibodies given in sequential fashion did not significantly change the imaging sensitivity from that seen with each individual antibody

Micrometastatic cancer cells in bone marrow: in vitro detection with anti-cytokeratin and in vivo labeling with anti-17-1A monoclonal antibodies

International Nuclear Information System (INIS)

Schlimok, G.; Funke, I.; Holzmann, B.

1987-01-01

The detection of early micrometastasis or disseminated single tumor cells poses a problem for conventional diagnosis procedures. Using a panel of monoclonal antibodies against cytokeratin and the 17-1A epithelial antigen the authors identified immunocytochemically tumor cells in bone marrow of patients with breast cancer and colorectal cancer at the time of surgery of the primary tumor. Monoclonal antibody CK2, recognizing the human cytokeratin component 18 in simple epithelia, appeared to be the most suitable reagent because of its negative reaction with bone marrow samples of the noncarcinoma patients. Its specificity was further demonstrated in a double-marker staining procedure using an anti-leukocyte common antigen monoclonal antibody (T200) as counterstain. A comparative analysis showed that immunocytology was clearly superior to conventional cytology and histology. In 9.5-20.5% of patients without distant metastasis, tumor cells could be detected in bone marrow. They found a significant correlation between tumor cells in bone marrow and conventional risk factors, such as distant metastasis or lymph node involvement. In a first approach toward immunotherapy they demonstrated in 3 patients that infused monoclonal antibody 17-1A can label single tumor cells in bone marrow in vivo. They then used this single approach to follow up on 7 patients undergoing 17-1A therapy in an adjuvant clinical trial

Immunoassay of 5-methyltetrahydrofolate: use of 125I-labeled protein A as the tracer molecule for specific antibody

International Nuclear Information System (INIS)

Langone, J.J.

1980-01-01

A sensitive and specific solid-phase radioimmunoassay for 5-methyltetrahydrofolate (5-MTHFA) has been developed. 125 I-Labeled staphylococcal Protein A ( 125 I-PA) was used as the tracer molecule for rabbit IgG antibodies bound to 5-MTHFA immobilized on polyacrylamide beads. The dose-dependent inhibition of antibody binding by fluid-phase drug was reflected in decreased binding of 125 I-PA. This inhibition, determined in the presence of known amounts of 5-MTHFA, served as the basis for quantification of 5-MTHFA in test samples. An early bleeding was relatively specific; 4.5 ng 5-MTHFA inhibited immune binding by 50% compared to 7700 ng folinic acid or 1200 ng tetrahydrofolate. Other folic acid analogs, including methotrexate, failed to inhibit significantly. The assay using a later bleeding was more sensitive since 1.6 ng 5-MTHFA gave 50% inhibition (detection limit 0.2 ng), but folinic acid cross-reacted significantly. Absorption with immobilized folinic acid markedly enhanced the specificity of this antiserum and resulted in a 15 to 20% increase in maximum inhibition by 5-MTHFA. The assay could be carried out in the presence of 0.025 ml human serum or urine without affecting the standard curve, and was used to determine levels of 5-MTHFA in serum of drug-treated rabbits

Radioimmunodetection of hepatocellular carcinoma with a radiolabeled antibody to alpha fetoprotein

International Nuclear Information System (INIS)

Ishii, Nobuko; Nakata, Keisuke; Muro, Toyokichi

1982-01-01

The present study was undertaken to investigate whether or not radiolabeled antibody to Alpha-fetoprotein (AFP) intravenously administered is accumulate in AFP-producing tumors. Rats with subcutaneously transplanted hepatoma or with heptoma produced in liver by 3'-Me-DAB, and 12 patients with hepatocellular carcinoma (HCC) were studied. In animal experiments, the tumor localization was clearly demonstrated by total body scintigraphy 48 to 168 hours after the injection of the radioiodinated antibody. The rats were sacrificed and radioactivity in tissues was counted. Tumor tissues showed the highest counts. In patients with HCC, the imaging was made with a gamma camera usually 24 and 48 hours after injection of I-131-labeled antibody. In order to make the contrast of tumor image clear, nonspecific background images obtained by administration of Tc-99m-labeled serum albumin were subtracted from the images obtained by I-131 labeled antibody with a computer. In 6 of 12 patients with HCC, the tumor location could successfully demonstrated. However, tumor with sizes below 2 cm in diameter which were able to be detected by the celiac angiography were not detectable. Interes tingly the images were more clear in patients with relatively higher serum AFP levels. In the blood of patient given injection of AFP radioantibody, both immune complex and free antibody were able to be detected at least for 120 hours so that the presence of free antigen (AFP) did not appear to prevent tumor radioimmunodetection. The information obtained concerning the biochemical factors which influence antibody localization in the tumor would provide better method for radioimmunodetection with antitumor antibodies. (author)

Cancer imaging with CEA antibodies: historical and current perspectives.

Science.gov (United States)

Goldenberg, D M

1992-01-01

This article reviews the history and status of cancer imaging with radiolabeled antibodies against carcinoembryonic antigen (CEA). Although CEA and many other cancer-associated antigens are not distinct for neoplasia, the quantitative increase of these markers in malignant tissues provides a sufficient differential for selective antibody targeting. Animal studies with xenografted human tumors provided the first evidence of the prospects of this technology, followed by initial clinical success with purified goat whole IgG antibodies to CEA, labeled with 131I and with the use of dual-isotope subtraction methods. Subsequently, improved and earlier imaging could be accomplished with monoclonal antibody fragments, which then would permit the use of shorter-lived radionuclides, such as 111In, 123I, and 99mTc. The preferred use of a monoclonal anti-CEA IgG Fab' fragment, labeled with 99mTc by a recently developed, simple and rapid kit, has enabled the detection of small lesions, including those in the liver, within 4 h of injection. By means of SPECT imaging, a high sensitivity and specificity for RAID could be achieved.

Molecular imaging needles: dual-modality optical coherence tomography and fluorescence imaging of labeled antibodies deep in tissue

Science.gov (United States)

Scolaro, Loretta; Lorenser, Dirk; Madore, Wendy-Julie; Kirk, Rodney W.; Kramer, Anne S.; Yeoh, George C.; Godbout, Nicolas; Sampson, David D.; Boudoux, Caroline; McLaughlin, Robert A.

2015-01-01

Molecular imaging using optical techniques provides insight into disease at the cellular level. In this paper, we report on a novel dual-modality probe capable of performing molecular imaging by combining simultaneous three-dimensional optical coherence tomography (OCT) and two-dimensional fluorescence imaging in a hypodermic needle. The probe, referred to as a molecular imaging (MI) needle, may be inserted tens of millimeters into tissue. The MI needle utilizes double-clad fiber to carry both imaging modalities, and is interfaced to a 1310-nm OCT system and a fluorescence imaging subsystem using an asymmetrical double-clad fiber coupler customized to achieve high fluorescence collection efficiency. We present, to the best of our knowledge, the first dual-modality OCT and fluorescence needle probe with sufficient sensitivity to image fluorescently labeled antibodies. Such probes enable high-resolution molecular imaging deep within tissue. PMID:26137379

Radiolabelled antibody imaging

International Nuclear Information System (INIS)

Perkins, A.C.

1986-01-01

A steadily growing number of tumor-associated antigens are used to raise antibodies used for the detection of human tumors by external imaging, a technique termed immunoscintigraphy. The majority of these clinical antibody studies are performed using Iodine-131, which is cheap, readily available and easily attached to protein. It has the disadvantage of having a high energy gamma emission (365 keV) which is poorly detected by modern cameras, so that increasing use is now being made of more appropriate labels with lower energies for imaging, such as Iodine-123, Indium-111 and Technetium-99m. A number of research centres in the United Kingdom are currently involved in the production of tumor-associated monoclonal antibodies, only a small number of which are finally selected for diagnostic use. These developments represent a major area of advancement in Nuclear Medicine and when used for imaging are capable of providing diagnostic information complimentary to other diagnostic techniques

NMR Detection of Semi-Specific Antibody Interactions in Serum Environments

Directory of Open Access Journals (Sweden)

Saeko Yanaka

2017-09-01

Full Text Available Although antibody functions are executed in heterogeneous blood streams characterized by molecular crowding and promiscuous intermolecular interaction, detailed structural characterizations of antibody interactions have thus far been performed under homogeneous in vitro conditions. NMR spectroscopy potentially has the ability to study protein structures in heterogeneous environments, assuming that the target protein can be labeled with NMR-active isotopes. Based on our successful development of isotope labeling of antibody glycoproteins, here we apply NMR spectroscopy to characterize antibody interactions in heterogeneous extracellular environments using mouse IgG-Fc as a test molecule. In human serum, many of the HSQC peaks originating from the Fc backbone exhibited attenuation in intensity of various magnitudes. Similar spectral changes were induced by the Fab fragment of polyclonal IgG isolated from the serum, but not by serum albumin, indicating that a subset of antibodies reactive with mouse IgG-Fc exists in human serum without preimmunization. The metaepitopes recognized by serum polyclonal IgG cover the entire molecular surface of Fc, including the binding sites to Fc receptors and C1q. In-serum NMR observation will offer useful tools for the detailed characterization of biopharamaceuticals, including therapeutic antibodies in physiologically relevant heterogeneous environments, also giving deeper insight into molecular recognition by polyclonal antibodies in the immune system.

Anti‑livin antibodies in Hashimoto thyroiditis.

Science.gov (United States)

Baumann-Antczak, Aleksandra; Kosowicz, Jerzy; Zamysłowska, Hanna; Ruchała, Marek

2012-01-01

Livin belongs to the family of apoptosis inhibitors. High livin expression is observed in malignancies of the gastrointestinal tract, lungs, breast, and kidneys, but it is not present in differentiated adult tissues. In some malignant processes, anti‑livin antibodies are present. The aim of the study was to evaluate the prevalence of anti‑livin antibodies in Hashimoto thyroiditis, a disease characterized by rapid and widespread thyrocyte apoptosis. The study comprised 65 women with Hashimoto thyroiditis and the control group of 40 healthy women. In the majority of the patients, clinical manifestations of hypothyroidism were observed; all patients had high levels of serum antithyroid peroxidase antibodies. A solid‑phase radioimmunoassay in livin‑coated polyethylene tubes using 125I-labeled protein A was used to determine anti-livin antibodies. Significant amounts of anti-livin antibodies were reported in 18 patients (26.8%); 3 patients (4.6%) had borderline antibody levels; while in controls only 1 patient was positive (2.5%, P Hashimoto thyroiditis, an autoimmune process is more general and involves numerous autoantibodies including an antibody against apoptosis inhibitor - livin. Anti‑livin antibodies cannot serve only as a marker of malignancy because they are also present in autoimmune processes.

Development of radioactively labelled cancer seeking biomolecules for targeted radiotherapy. Greece

International Nuclear Information System (INIS)

Varvarigou, Alexandra D.; Archimandritis, Spyridon C.

2000-01-01

Within the framework of the above project we are studying the labelling of biomolecules, peptides and antibodies, with radionuclides emitting β - and γ radiation. More specifically, for the time being, we have investigated the labelling of peptides with Re-188 and of antibodies with Sm-153 and Re-188. The radiolabelled derivatives are further evaluated in vivo for possible application in Oncology. For these radiobiological studies we are trying to apply ectopic and orthotopic tumour animal models and to develop, in collaboration with other national and foreign institutes, proper imaging devices for small animal imaging

A fluorescence sedimentation assay for dsDNA antibodies

DEFF Research Database (Denmark)

Duus, K; Draborg, A H; Güven, E

2017-01-01

The Farr assay is a radioimmunoassay (RIA) for dsDNA antibodies, based on antibody precipitation using ammonium sulphate and quantification using radio-labelled dsDNA. The RIA-Farr assay offers outstanding clinical specificity and sensitivity for systemic lupus erythematosus (SLE) compared to other...... on precipitation with polyethylene glycol (PEG) and fluorescence of EvaGreen intercalated in dsDNA as detection principle. As dsDNA antibodies are quantified using fluorescence, the disadvantages of working with radioactivity are eliminated. The Fluoro-Farr assay was developed and validated, and the diagnostic...

Dosimetry of radiolabeled monoclonal antibodies used for therapy

International Nuclear Information System (INIS)

Myers, M.J.; Hooker, G.R.; Epenetos, A.A.

1986-01-01

The present state of radiotherapy using labeled antibodies is reviewed. From the point of view of dosimetry, antibody therapy does not seem to have reached a stable and practicable enough state to provide an input to any but rather tentative dosimetry models. These, therefore, should not be taken too far until the problems of antibody targeting have been more fully developed. Some of the instrumental techniques for acquiring dosimetric data under clinical conditions are discussed as are some of the techniques of therapy in use today. 8 references, 3 figures

Biodistribution of {sup 99m}Tc-labeled anti-human epidermal growth factor receptor (EGF-R) humanized monoclonal antibody h-R3 in a xenograft model of human lung adenocarcinoma

Energy Technology Data Exchange (ETDEWEB)

Morales-Morales, Alejo; Duconge, Jorge; Caballero-Torres, Idania; Nunez-Gandolff, Gilda; Fernandez, Eduardo; Iznaga-Escobar, Normando E-mail: normando@ict.cim.sld.cu

1999-04-01

The anti-human epidermal growth factor receptor (EGF-R) humanized monoclonal antibody (MAb) h-R3 is an (IgG{sub 1}), which binds to an extracellular domain of EGF-R. It was used to evaluate the biodistribution on nude mice xenografted with H-125 human lung adenocarcinoma cell line. Results were compared with its murine version of the MAb ior-egf/r3. Twenty-one athymic female 4NMRI nu/nu mice were injected intraperitoneally with 10 {mu}g/100 {mu}Ci of {sup 99m}Tc-labeled MAbs. Immunoreactivity of {sup 99m}Tc-labeled MAbs were measured by enzyme-linked immunosorbent assay (ELISA) on H-125 cell line and the immunoreactive fractions was determined by the Lindmo method. Among all organs, significant accumulation was found in serum (27.05 {+-} 2.08 %ID/g) and tumor (3.903 {+-} 0.89 %ID/g) at 4 h after injection. These values decreased to 5.03 {+-} 0.50 %ID/g and 2.19 {+-} 0.56 %ID/g for serum and tumor, respectively. The immunoreactive fraction was found to be 0.70, with a correlation coefficient r=0.9984. With the good biodistribution and tumor uptake of the {sup 99m}Tc-labeled humanized antibody h-R3, a phase I diagnostic clinical trial of tumor with epithelial origin should be pursued.

Radiolabelled monoclonal antibodies against alpha-fetoprotein for in vivo localization of human hepatocellular carcinoma by immunotomoscintigraphy

International Nuclear Information System (INIS)

Bergmann, J.F.; Lumbroso, J.D.; Manil, L.; Saccavini, J.C.; Rougier, P.; Assicot, M.; Mathieu, A.; Bellet, D.; Bohuon, C.

1987-01-01

Two high affinity monoclonal antibodies, designated AF01 and AF04, directed against distinct epitopes of human alpha-fetoprotein (AFP) and the Fab fragments of one of them, were labelled with 131 I and injected into 18 patients with AFP producing hepatocellular carcinoma (HCC) in order to carry out imaging studies by tomoscintigraphy. Twelve patients were injected with whole antibody, only three of seven patients injected with AF01 and two of five patients injected with AF04 had a positive scan. In contrast, five out of six patients injected with labelled Fab fragments of AF04 had positive imaging. These results confirm that tumour imaging of HCC using 131 I labelled monoclonal antibody against AFP is feasible. Moreover, utilization of tomoscintigraphy in place of linear scintigraphy and Fab fragments instead of whole immunoglobulin may improve the sensitivity of radioimmunolocalization. This technique provides useful information on the in vivo distribution of monoclonal antibodies directed against AFP and on the practicability of the eventual therapeutic use of anti-AFP antibodies in HCC. (orig.)

Changes in immunoferritin labeling of Rickettsia tsutsugamushi after serial cultivation in 60Co-irradiated BHK cells

International Nuclear Information System (INIS)

Rikihisa, Y.; Rota, T.; Lee, T.H.; MacDonald, A.B.; Ito, S.

1979-01-01

The immunolabeling characteritics of Rickettsia tsutsugamushi (Gilliam strain) were examined by using a purified immunoglobulin G fraction of antibody to R. tsutsugamushi raised in rabbits. When rickettsiae in BHK-21 cells infected from yolk sac seed material were immunoferritin labeled, the binding of ferritin was found to be dense and uniform on the outer surface of the rickettsiae in disrupted host cells. Immunolabeling of purified suspensions of extracellular rickettsiae resulted in the uniform ferritin labeling of the microorganism. The immunoferritin labeling of R. tsutsugamushi during successive serial passages in BHK-21 cells revealed decreased labeling with each passage, and by the 10th passage there was no detectable labeling. However, these rickettsiae inoculated back into yolk sacs regained their immunoferritin labeling. Antibody against rickettsiae cultivated in BHK-21 cells continued labeling rickettsiae even after 9 serial passages in BHK-21 cells

Two-monoclonal-antibody sandwich-type assay for thyrotropin, with use of an avidin-biotin separation technique

International Nuclear Information System (INIS)

Odell, W.D.; Griffin, J.; Zahradnik, R.

1986-01-01

We have developed a sensitive, specific, noncompetitive, sandwich-type radioimmunoassay for human thyrotropin (hTSH), which can be performed in 30 min. The assay involves two monoclonal antibodies, selected for high affinity and specificity and also for reaction against antigenic sites on hTSH that are distal from each other. One of these antibodies is labeled with 125 I; the other is conjugated covalently to biotin. Polystyrene beads were also conjugated covalently to biotin. After conjugation, the beads were incubated with avidin. These beads represent a rapid, simple method for separating hTSH-bound antibody from free antibody. The biotin-antibody-hTSH- 125 I-labeled antibody complexes bind to the beads and hTSH concentration is directly related to counts per minute. This assay can detect hTSH at a concentration of 0.06 milli-unit/L in serum

The effects of variations in the specificities of the antibody components on a two-site immunoradiometric assay for ferritin

International Nuclear Information System (INIS)

Cowan, S.I.; Stagg, B.H.; Niemann, E.

1977-01-01

Variations in the sub-unit antigenic structure of ferritins derived from various human tissues are reflected in the differing specificities of antisera raised against these ferritin preparations. In this study it was shown that antibody specificity played an important role in determining the sensitivity and overall binding of labelled antibody in a two-site immunoradiometric assay for ferritin. Homologous assay systems, in which solid phase and radiolabelled antibodies were of similar specificities, were generally less sensitive and showed lower binding than heterologous assay systems, in which solid phase and labelled antibodies were of different specificities. The source of the ferritin which was used as assay standard also played an important part in determining the sensitivity and overall binding in homologous antibody systems, spleen ferritin standards yielding assays superior to those obtained with placenta or liver ferritin standards. However, these differences between standards were not seen in a heterologous system employing solid phase antibodies directed against liver ferritin and labelled antibodies directed against placenta ferritin. The nature of the ferritin used to prepare immunoadsorbant for the purification of antibodies prior to radioiodination also affected the assay characteristics; antibodies prepared on spleen ferritin immunoadsorbant being more reactive than antibodies prepared on placenta ferritin immunoadsorbant, which in turn were more reactive then antibodies prepared on liver ferritin immunoadsorbant. (orig.) [de

A new monoclonal antibody for the radio immune diagnosis of colorectal cancer

International Nuclear Information System (INIS)

Ramos, M.

1997-01-01

Colorectal cancer is the third cause of death among malignant neoplasms in Cuba. Different labeled monoclonal antibodies have been used for the diagnosis and follow-up of this tumors bu immunoscintigraphy. Recently, a new MAB ior c5 have been developed at Center of Molecular Immunology, Havana, Cuba. It recognizes a new tumors associated antigen: IOR C2, found in most of colorectal adenocarcinomas. The aim of the present work was to assess the diagnostic utility of this antibody, Labelled with 99m Tc, as well as to study its pharmacokinetics, biodistribution and internal dosimetry

Photoelectronic characterization of IgG antibody molecule-quantum dot hybrid as biosensing probe

Energy Technology Data Exchange (ETDEWEB)

Yu, Hye-Weon; Kim, Sung-Jo; Kim, In S [School of Environmental Science and Engineering, Gwangju Institute of Science and Technology (GIST), 261 Cheomdan-gwagiro, Buk-gu, Gwangju 500-712 (Korea, Republic of); Lee, Jinwook; Kim, Sungyoun, E-mail: iskim@gist.ac.kr [Center for Seawater Desalination Plant, Gwangju Institute of Science and Technology (GIST), 261 Cheomdan-gwagiro, Buk-gu, Gwangju 500-712 (Korea, Republic of)

2010-10-22

Quantum dot (QD)-based biomolecule hybrids have recently attracted much attention in specifically identifying and labeling target proteins. In this study, QD encapsulated with immunoglobulin antibodies, as a labeling building block in biosensors, was investigated to clarify the most efficient configuration and photoluminescence behavior. Both the biological recognition capacity and photoluminescence emitting signal of the antibody-coupled nanocrystal were validated through a photoelectrical characterization procedure. Derivation of the optimum number of antibody molecules to be packed onto the QD surface yielded the highest binding capacity for the target antigen. During formation of the bioactive layer, the intrinsic photoluminescence response of the QDs significantly decreased due to photoinduced hole transfer according to their rearranged electronic structure. The thorough study of this assembly provides a validation approach for the careful titration of biosensor probes for optimal reaction kinetics. Furthermore, it contributes to the development of an effective tool for the application and interpretation of QD-based labeling techniques.

Photoelectronic characterization of IgG antibody molecule-quantum dot hybrid as biosensing probe

International Nuclear Information System (INIS)

Yu, Hye-Weon; Kim, Sung-Jo; Kim, In S; Lee, Jinwook; Kim, Sungyoun

2010-01-01

Quantum dot (QD)-based biomolecule hybrids have recently attracted much attention in specifically identifying and labeling target proteins. In this study, QD encapsulated with immunoglobulin antibodies, as a labeling building block in biosensors, was investigated to clarify the most efficient configuration and photoluminescence behavior. Both the biological recognition capacity and photoluminescence emitting signal of the antibody-coupled nanocrystal were validated through a photoelectrical characterization procedure. Derivation of the optimum number of antibody molecules to be packed onto the QD surface yielded the highest binding capacity for the target antigen. During formation of the bioactive layer, the intrinsic photoluminescence response of the QDs significantly decreased due to photoinduced hole transfer according to their rearranged electronic structure. The thorough study of this assembly provides a validation approach for the careful titration of biosensor probes for optimal reaction kinetics. Furthermore, it contributes to the development of an effective tool for the application and interpretation of QD-based labeling techniques.

Monoclonal antibodies for radioimmunodetection of tumours and for targeting

International Nuclear Information System (INIS)

Baldwin, R.W.; Embleton, M.J.; Pimm, M.V.

1983-01-01

A monoclonal antibody 791T/36 prepared against human osteogenic sarcoma has been used to detect primary and metastatic colorectal carcinomas by external imaging of patients following injection of 131 I-labelled antibody. In 10 of 11 patients radiolabelled 791T/36 antibody localized in tumours, the tumour/non tumour ratio of radioactivity ranging from 1.5:1 to 8.1. 791T/36 antibody was also evaluated for its potential for targeting anti-tumour agents including cytotoxic drugs (Vindesine) and immunomodulating agents (interferon). Vindesine-791T/36 conjugates were preferentially cytotoxic in vitro for target cells expressing the 791T/36 anti-body defined antigen. Also interferon conjugated to 791T/36 antibody, like free interferon activated peripheral blood natural killer cell activity. These in vitro tests together with related studies on antibody localization in vivo indicate the potential of monoclonal antibody targeting of anti-tumour agents

Carbon-13 NMR study of switch variant anti-dansyl antibodies: Antigen binding and domain-domain interactions

International Nuclear Information System (INIS)

Kato, Koichi; Matsunaga, Chigusa; Odaka, Asano; Yamato, Sumie; Takaha, Wakana; Shimada, Ichio; Arata, Yoji

1991-01-01

A 13 C NMR study is reported of switch variant anti-dansyl antibodies, which possess the identical V H , V L , and C L domains in conjunction with highly homologous but not identical heavy-chain constant regions. Each of the antibodies has been selectively labeled with 13 C at the carbonyl carbon of Trp, Tyr, His, or Cys residue by growing hybridoma cells in serum-free medium. Spectral assignments have been made by folowing the procedure described previously for the switch variant antibodies labeled with [1- 13 C]Met. On the basis of the spectral data collected for the antibodies and their proteolytic fragments, the authors discuss how 13 C NMR spectroscopy can be used for the structural analyses of antigen binding and also of domain-domain interactions in the antibody molecule

Radioimmunolocalisation of tumours by external scintigraphy after administration of 131I antibody to carcinoembryonic antigen

International Nuclear Information System (INIS)

Searle, F.; Bagshawe, K.D.; Begent, R.H.J.; Jewkes, R.F.; Jones, B.E.; Keep, P.A.; Lewis, J.; Vernon, P.

1980-01-01

Investigations of 131 I-labelled antibody to carcinoembryonic antigen (CEA) were performed in nude mice bearing human colonic carcinoma xenografts and in external scintigraphy of patients with various tumours. In mice, the activities of 131 I (antiCEA) and 125 I(normal γ globulin) were measured in the human colon carcinoma xenografts. The results were expressed as a ratio of uptake of specific to non-specific antibody showing that antiCEA was retained in the tumours with a maximum specificity index of 2.2 at 7 days after antibody administration. Palpable carcinomas of the colon were localised by scintiscanning in patients given 131 I-labelled antibody to CEA. However, uptake of antiCEA was also demonstrated in apparently normal colon due to non-specific uptake of antibody and the fact that some CEA is present in normal colon. Thus further development of the technique particularly as regards antibody specificity, is necessary before radioimmunolocalisation could be used as a means of detecting tumours in clinical practice. (UK)

Alpha radioisotopes Ac-225 and Bi-213: a production and labelling of antibodies and peptides for clinical use

Energy Technology Data Exchange (ETDEWEB)

Bruchertseifer, Frank, E-mail: frank.bruchertseifer@ec.europa.eu [European Commission, Joint Research Centre, Karlsruhe (Germany)

2017-07-01

Full text: In various preclinical and clinical works the potential of the alpha emitters {sup 225}Ac and {sup 213}Bi as therapeutic radionuclides for application in targeted alpha therapy of cancer and infectious diseases was demonstrated. Both alpha emitters are available with high specific activity from established radionuclide generators. Their favorable chemical and physical properties have led to the conduction of a large number of preclinical studies and several clinical trials, demonstrating the feasibility, safety and therapeutic efficacy of targeted alpha therapy with {sup 225}Ac and {sup 213}Bi. This presentation will give an overview about the methods for the production of {sup 225}Ac and {sup 213}Bi, the {sup 225}Ac/{sup 213}Bi radionuclide generator systems, labelling of peptides and antibodies with {sup 225}Ac and {sup 213}Bi and relevant in vivo and in vitro works. (author)

Breast cancer imaging with mouse monoclonal antibodies

Energy Technology Data Exchange (ETDEWEB)

Major, P.; Wang Taqui; Unger, M.; Rosenthall, L.

1989-10-01

The localization of /sup 111/In-labelled MA5 monoclonal antibody, reactive with a breast tumor associated antigen, was studied in 17 patients. MA5 was selected because (1) it reacts with >95% of primary and metastatic lesions, (2) the recognized antigen is present on the cell surface in vivo and (3) MA5 gives excellent localization in human breast tumor xenografts. Each patient received 2 mg antibody labeled with 5 mCi /sup 111/In and in some cases, 3 mg or 18 mg unlabeled carrier antibody. No serious allergic reactions were noted. There was a large uptake in the liver, less significant uptake in the spleen and bone and minimal accumulation in the bowel. Bone lesions, primary tumors, soft tissue recurrences and lung metastases larger than 3 cm diameter were imaged, while only 1 lesion smaller than 3 cm was detected. Non specific accumulation of tracer was noted at the site of a port-a-cath, in a hematoma, in fibrocystic lesions, and at sites of previous radiation treatment. Extensive fibrosis and poor vascularization characteristic of breast tumors may explain in part the limited sensitivity of the imaging. (orig.).

Imaging thrombus with radiolabelled monoclonal antibody to platelets

International Nuclear Information System (INIS)

Loutfi, I.; Peters, A.M.; Lavender, J.P.; Epenetos, A.A.

1988-01-01

Indium-111-hydroxyquinoline labelled platelets, though useful in the detection of thrombus, have not gained widespread use owing to the time and technical skill required for their preparation. A study was therefore conducted evaluating a new method of imaging thrombus with platelets radiolabelled with a 111 In labelled monoclonal antibody, P 256 , directed to the platelet surface glycoprotein complex IIb/IIIa. When the number of receptors occupied by P 256 was less than 3% of the total available on the platelet surface platelet function, as assessed by platelet aggregometry, was undisturbed. P 256 was radiolabelled with 111 In using diethylenetriaminepenta-acetic acid, which achieved a specific activity of 185 MBq (5 mCi)/mg. No impairment of immunoreactivity was detected at this specific activity. Platelets were labelled with radiolabelled monoclonal antibody in vitro in two patients at a receptor occupancy of 6% and in vivo - that is, by direct intravenous injection of P 256 - in six patients at a receptor occupancy of 1%. In vivo recovery and biodistribution kinetics suggested that after in vitro labelling platelets were minimally activated. The 111 In kinetics recorded after intravenous P 256 suggested rapid and efficient radiolabelling of platelets and gave no indication of platelet activation. Of the six patients who received intravenous P 256 , three had documented thrombus, tow of whom gave positive results on P 256 platelet scintigraphy. The third subject had chromic deep venous thrombosis and was scintigraphically negative. Imaging thrombus using a radiolabelled monoclonal antibody directed to platelets appears to offer great potential as a simple, non-invasive approach to the diagnosis of thrombosis. 3 refs. (Author)

Surface-Enhanced Raman Scattering Nanoparticles as Optical Labels for Imaging Cell Surface Proteins

Science.gov (United States)

MacLaughlin, Christina M.

Assaying the expression of cell surface proteins has widespread application for characterizing cell type, developmental stage, and monitoring disease transformation. Immunophenotyping is conducted by treating cells with labelled targeting moieties that have high affinity for relevant surface protein(s). The sensitivity and specificity of immunophenotyping is defined by the choice of contrast agent and therefore, the number of resolvable signals that can be used to simultaneously label cells. Narrow band width surface-enhanced Raman scattering (SERS) nanoparticles are proposed as optical labels for multiplexed immunophenotying. Two types of surface coatings were investigated to passivate the gold nanoparticles, incorporate SERS functionality, and to facilitate attachment of targeting antibodies. Thiolated poly(ethylene glycol) forms dative bonds with the gold surface and is compatible with multiple physisorbed Raman-active reporter molecules. Ternary lipid bilayers are used to encapsulate the gold nanoparticles particles, and incorporate three different classes of Raman reporters. TEM, UV-Visible absorbance spectroscopy, DLS, and electrophoretic light scattering were used characterize the particle coating. Colourimetric protein assay, and secondary antibody labelling were used to quantify the antibody conjugation. Three different in vitromodels were used to investigate the binding efficacy and specificity of SERS labels for their biomarker targets. Primary human CLL cells, LY10 B lymphoma, and A549 adenocarcinoma lines were targeted. Dark field imaging was used to visualize the colocalization of SERS labels with cells, and evidence of receptor clustering was obtained based on colour shifts of the particles' Rayleigh scattering. Widefield, and spatially-resolved Raman spectra were used to detect labels singly, and in combination from labelled cells. Fluorescence flow cytometry was used to test the particles' binding specificity, and SERS from labelled cells was also

Initial study with Tc99m antigranulocyte antibody (MAK-47) in detection sources of infection

International Nuclear Information System (INIS)

Cwikla, J.B.; Buscombe, J.R.; Hilson, A.J.; Janoki, G.A.

1997-01-01

Antigranulocytes antibodies (AGAB) are antibodies directed against glycoprotein on the surface of granulocytes and as such provides in vivo cell labelling. They are easily labelled with Tc99m and comes a one step labelling technique. 20 patients have been studied 1 h and 4-6 hours after administration of 200 MBq of Tc99m AGAB (MAK-47). Less then 0.5 mg of antibody was given to each patients. Sites of uptake and outside of the reticular-endothelial system were reported as showing positive accumulation. Clinical results were confirmed by microbiological, pathological examinations, clinical follow-up and autopsy. There were 8 patients who had sites of infection confirmed by additional examination. All patients were visualized by Tc99m AGAB (MAK-47). There were 4 cases of osteomyelitis and septic arthritis and 4 cases of focal intra-abdominal infection. Two patients had uptake in non-infected/inflammatory arthritis, both in the knee. The remaining patients had true negative studies. The diagnostic accuracy of this study was as follows: sensitivity 100%, specificity 83%, positive predictive value (PPV) was 80% and negative predictive value (NPV) was 100%. Antigranulocyte antibody (MAK-47) seems to by promising tool in detecting focal infection in bone and soft tissue, except physiological accumulation in some parts of the body. It should be considered that antibodies can have non-specific uptake in non-infected, inflammation sites. It is easy to use and no had allergic reaction and HAMA antibody (human antimouse antibody). (author)

Verification of the Cross Immunoreactivity of A60, a Mouse Monoclonal Antibody against Neuronal Nuclear Protein.

Science.gov (United States)

Mao, Shanping; Xiong, Guoxiang; Zhang, Lei; Dong, Huimin; Liu, Baohui; Cohen, Noam A; Cohen, Akiva S

2016-01-01

A60, the mouse monoclonal antibody against the neuronal nuclear protein (NeuN), is the most widely used neuronal marker in neuroscience research and neuropathological assays. Previous studies identified fragments of A60-immunoprecipitated protein as Synapsin I (Syn I), suggesting the antibody will demonstrate cross immunoreactivity. However, the likelihood of cross reactivity has never been verified by immunohistochemical techniques. Using our established tissue processing and immunofluorescent staining protocols, we found that A60 consistently labeled mossy fiber terminals in hippocampal area CA3. These A60-positive mossy fiber terminals could also be labeled by Syn I antibody. After treating brain slices with saponin in order to better preserve various membrane and/or vesicular proteins for immunostaining, we observed that A60 could also label additional synapses in various brain areas. Therefore, we used A60 together with a rabbit monoclonal NeuN antibody to confirm the existence of this cross reactivity. We showed that the putative band positive for A60 and Syn I could not be detected by the rabbit anti-NeuN in Western blotting. As efficient as Millipore A60 to recognize neuronal nuclei, the rabbit NeuN antibody demonstrated no labeling of synaptic structures in immunofluorescent staining. The present study successfully verified the cross reactivity present in immunohistochemistry, cautioning that A60 may not be the ideal biomarker to verify neuronal identity due to its cross immunoreactivity. In contrast, the rabbit monoclonal NeuN antibody used in this study may be a better candidate to substitute for A60.

Pharmacokinetics, biodistribution and dosimetry of {sup 99m}Tc-labeled anti-human epidermal growth factor receptor humanized monoclonal antibody R3 in rats

Energy Technology Data Exchange (ETDEWEB)

Escobar, Normando Iznaga; Morales, Alejo Morales; Duconge, Jorge; Torres, Idania Caballero; Fernandez, Eduardo; Gomez, Jose A

1998-01-01

The pharmacokinetics, biodistribution and dosimetry of {sup 99m}Tc-labeled anti-human epidermal growth factor receptor (anti-hEGF-r) humanized monoclonal antibody (MAb) R3 was investigated following intravenous injection in normal Wistar rats. Serum disappearance curves were best fit by a two-compartment model having a mean distribution half-life (t{sub (1(2{alpha}}{sub ))}) of 0.250 h and a mean elimination (t{sub (1(2{beta}}{sub ))}) of 13.89 h. Among the various organs, a little accumulation of the radiolabeled antibody was found only in kidneys. Biodistribution and dosimetry studies in humans were performed by extrapolation of the animal data to humans. Absorbed dose to normal organs and the remainder of the whole body were estimated using the medical internal radiation dose formula, and dose contributions from radioactivity in transit through the gastrointestinal tract were estimated using a compartment model. Extrapolated values of radiation absorbed dose to normal organs in rads per millicurie administered were whole body, 0.0085; lower large intestine wall, 0.0898; small intestine, 0.0530; upper large intestine wall, 0.0731; and kidneys, 0.0455. The effective dose equivalent predicted was 0.0162 rem/mCi and the effective dose was found to be 0.015 rem/mCi. On the basis of the pharmacokinetics, biodistribution and internal radiation dosimetry information obtained in this study, a diagnostic phase I clinical trial with {sup 99m}Tc-labeled humanized MAb R3 conjugate in patients should be supported.

Monoclonal antibodies in oncology. Review article

Energy Technology Data Exchange (ETDEWEB)

Chan, S Y.T.; Sikora, K

1986-05-01

Monoclonal antibodies (MCAs) can be used to differentiate between normal and neoplastic cells and thus exploited for diagnostic and, ultimately, therapeutic gain. The evidence for the existence of human tumour antigens is reviewed. Several areas of diagnosis are already benefiting from the application of the monoclonal technology. Immunohistology can help the pathologist with difficult diagnostic problems. New classifications of lymphoma and leukaemia can be based on specific surface molecules. Similarly, the detection of shed tumour antigens is already established as part of the routine assessment of many patients with common solid tumours. Isotopically labeled monoclonal antibodies have been used to localise primary and metastatic tumours. The use of antibodies in this way is not only a promising diagnostic tool but also the first step in studying the possibility of arming antibodies to provide therapeutic agents. Such trials are currently in progress. 69 refs.; 7 figs.; 3 tabs.

Experimental study on 211At labelled monoclonal antibody 3H11 and its Fab fragment radioimmunotherapy for human gastric cancer xenografts in nude mice

International Nuclear Information System (INIS)

Jin Jiannan; Liu Ning; Zhang Shuyuan; Zhang Shiyuan; Luo Deyuan; Zhou Maolun

1996-01-01

Experimental radioimmunotherapy investigation of α-emitting radionuclide 211 At labelled anti-gastric cancer monoclonal antibody 3H11 and its Fab fragment for nude mice carrying human gastric cancer xenografts was conducted. Three i.p. injections of 14.8 or 22.2 kBq/g mouse were given, once every 5 days. The results showed that the growth of tumor xenografts was inhibited efficiently. The most evident therapy effect was observed at 15 days after treatment, and the tumor inhibition rates were 65% and 72%, respectively. No radiation injury of important organs was found

Radiolabeled monoclonal antibodies: a review

International Nuclear Information System (INIS)

Toledo e Souza, I.T. de; Okada, H.

1990-05-01

Since the description by Kohler and Milstein 1975 of their technique for producing monoclonal antibodies of predefined specificity, it has become a mainstay in most laboratories that utilize immunochemical techniques to study problems in basic, applied or clinical research. Paradoxically, the very success of monoclonal antibodies has generated a literature which is now so vast and scattered that it has become difficult to obtain a perspective. This brief review represents the distillation of many publications relating to the production and use of monoclonaal antibodies as radiopharmaceuticals. Significant advances were made possible in the last few years by combined developments in the fields of tumor-associated antigens and of monoclonal antibodies. In fact monoclonal antibodies against some well defined tumor-associated antigens, has led to significantly greater practical possibilities for producing highly specific radiolabeled antibodies as radiopharmaceuticals for diagnosis and therapy of human tumors. One of the main requirements of this methodology is the availability of stable radiopharmaceutical reagents which after labeling in vivo injection retain the capacity of specific interaction with the defined antigen and their molecular integrity. Since injection into human is the objetive of this kind of study all the specifications of radiopharmaceutical have to be fulfilled e.g. sterility, apirogenicity and absence of toxicity. (author) [pt

Horseradish peroxidase and antibody labeled gold nanoparticle probe for amplified immunoassay of ciguatoxin in fish samples based on capillary electrophoresis with electrochemical detection.

Science.gov (United States)

Zhang, Zhaoxiang; Liu, Ying; Zhang, Chaoying; Luan, Wenxiu

2015-03-01

This paper describes a new amplified immunoassay with horseradish peroxidase (HRP) and antibody (Ab) labeled gold nanoparticles (AuNPs) probe hyphenated to capillary electrophoresis (CE) with electrochemical (EC) detection for ultrasensitive determination of ciguatoxin CTX1B. AuNPs were conjugated with HRP and Ab, and then incubated with limited amount of CTX1B to produce immunocomplex. The immunoreactive sample was injected into capillary for CE separation and EC detection. Enhanced sensitivity was obtained by adopting the AuNPs as carriers of HRP and Ab at high HRP/Ab molar ratio. The calibration curve of CTX1B was in the range of 0.06-90 ng/mL. The detection limit was 0.045 ng/mL, which is 38-fold lower than that of HPLC-MS method for CTX1B analysis. The proposed method was successfully applied for the quantification of CTX1B in contamined fish samples by simultaneously labeling Ab and HRP on AuNPs. The amplified IA with HRP and Ab labeled AuNPs probe hyphenated to CE and EC detection provides a sensitive analytical approach for the determination of trace ciguatoxin in complex samples. Copyright © 2015 Elsevier Ltd. All rights reserved.

Biomolecule labelling by 186 Re

International Nuclear Information System (INIS)

Lungu, Valeria Viorica; Mihailescu, Gabriela; Dumitrescu, Gabriela

1998-01-01

The aim of this study is to develop and improve the existing radiolabelling techniques of peptides and monoclonal antibodies with 186 Re and 188 Re as potential agents for cancer targeted radiotherapy. We selected the following methods and techniques for direct labelling of peptides and monoclonal antibody: 1. Prereduction of -S-S- bridges of biomolecule to sulfhydryls using reducing agents: ascorbic acid, cysteine, active hydrogen, 2,3 dimercaptopropanol. The prereduction reactions are controlled by massic ratios of reduction agents/biomolecule, pH, temperature and time of incubation; 2. Reduction of 186 Re O 4 - stannous chloride in acid and alkaline pH; 3. Coupling reaction of 186 Re (red) with the biomolecule controlled by the time and temperature of incubation, the influence of pH regarding the binding of 186 Re to the biomolecules. The quality control was effected by chromatography techniques (paper and elution gel chromatography) on labeled biomolecule before and after purification. The elution gel chromatography was spectrophotometricaly monitored at 280 nm. In the same time the radioactivity of samples was measured using a gamma counter. All the results confirm in vitro stability of labeled biomolecule. The biological evaluation studies regarding accumulation and biological affinity will be controlled by scintigraphy method. Biodistribution studies will be effected to Walker tumor bearing animals at 4 and 24 hours after injections. (authors)

Quantitative cumulative biodistribution of antibodies in mice

Science.gov (United States)

Yip, Victor; Palma, Enzo; Tesar, Devin B; Mundo, Eduardo E; Bumbaca, Daniela; Torres, Elizabeth K; Reyes, Noe A; Shen, Ben Q; Fielder, Paul J; Prabhu, Saileta; Khawli, Leslie A; Boswell, C Andrew

2014-01-01

The neonatal Fc receptor (FcRn) plays an important and well-known role in antibody recycling in endothelial and hematopoietic cells and thus it influences the systemic pharmacokinetics (PK) of immunoglobulin G (IgG). However, considerably less is known about FcRn’s role in the metabolism of IgG within individual tissues after intravenous administration. To elucidate the organ distribution and gain insight into the metabolism of humanized IgG1 antibodies with different binding affinities FcRn, comparative biodistribution studies in normal CD-1 mice were conducted. Here, we generated variants of herpes simplex virus glycoprotein D-specific antibody (humanized anti-gD) with increased and decreased FcRn binding affinity by genetic engineering without affecting antigen specificity. These antibodies were expressed in Chinese hamster ovary cell lines, purified and paired radiolabeled with iodine-125 and indium-111. Equal amounts of I-125-labeled and In-111-labeled antibodies were mixed and intravenously administered into mice at 5 mg/kg. This approach allowed us to measure both the real-time IgG uptake (I-125) and cumulative uptake of IgG and catabolites (In-111) in individual tissues up to 1 week post-injection. The PK and distribution of the wild-type IgG and the variant with enhanced binding for FcRn were largely similar to each other, but vastly different for the rapidly cleared low-FcRn-binding variant. Uptake in individual tissues varied across time, FcRn binding affinity, and radiolabeling method. The liver and spleen emerged as the most concentrated sites of IgG catabolism in the absence of FcRn protection. These data provide an increased understanding of FcRn’s role in antibody PK and catabolism at the tissue level. PMID:24572100

Selection of matched pair of monoclonal antibodies for development of immunoradiometric assay (IRMA) : our experience with IRMA of TSH

International Nuclear Information System (INIS)

Kadwad, V.B.; Jyotsna, N.; Sivaprasad, N.

1998-01-01

Full text: In immunoradiometricassay (IRMA) two antibodies raised against two different epitopes of the same antigen are used, one bound to a solid phase (capture antibody) and the other labelled with 125 I (detector antibody). The development of any IRMA thus involves proper selection of the capture and detector antibody, preparation of solid phase, labelling of the antibody and assay optimization. Extensive studies have been carried out on these aspects in our laboratory with greater emphasis on the behavior of different pairs of antibodies as sandwich partners : monoclonal-monoclonal and monoclonal-polyclonal antibodies. The parameters studied include the ease of radio-iodination of different monoclonal antibodies, the effect of interchange of capture and detector antibody etc. Keeping TSH antibody as a model, two different monoclonal antibodies, a polyclonal antibody and a tracer from a commercial TSH IRMA kit were used in this study. Based on our studies an assay procedure for in-house IRMA of TSH has been developed with a sensitivity of 0.1 μIU/ml and validated

Immediate bromodeoxyuridine labelling of unseparated human bone marrow cells ex vivo is superior to labelling after routine laboratory processing

DEFF Research Database (Denmark)

Jensen, P O; Mortensen, B T; Christensen, I J

1998-01-01

It is important to evaluate the proliferation of bone marrow cells in several disease conditions and during treatment of patients with for example cytokines. Labelling with bromodeoxyuridine (BrdUrd), immunocytochemical staining with anti-BrdUrd antibody and analysis by flow cytometry provides...... a reliable and reproducible technique for estimation of the fraction of cells that incorporated BrdUrd into DNA during S-phase. We have compared immediate BrdUrd labelling of unseparated bone marrow cells with the previously used labelling in the laboratory after routine separation of the mononuclear cells....... Bone marrow aspirates from seven lymphoma patients without bone marrow involvement were studied with these two methods. We found higher BrdUrd labelling indices (LI) in the mononuclear cells, when cells were labelled immediately. A large variation in LI was found between patients. Our results suggest...

Carbon-13 NMR study of switch variant anti-dansyl antibodies: Antigen binding and domain-domain interactions

Energy Technology Data Exchange (ETDEWEB)

Kato, Koichi; Matsunaga, Chigusa; Odaka, Asano; Yamato, Sumie; Takaha, Wakana; Shimada, Ichio; Arata, Yoji (Univ. of Tokyo (Japan))

1991-07-02

A {sup 13}C NMR study is reported of switch variant anti-dansyl antibodies, which possess the identical V{sub H}, V{sub L}, and C{sub L} domains in conjunction with highly homologous but not identical heavy-chain constant regions. Each of the antibodies has been selectively labeled with {sup 13}C at the carbonyl carbon of Trp, Tyr, His, or Cys residue by growing hybridoma cells in serum-free medium. Spectral assignments have been made by folowing the procedure described previously for the switch variant antibodies labeled with (1-{sup 13}C)Met. On the basis of the spectral data collected for the antibodies and their proteolytic fragments, the authors discuss how {sup 13}C NMR spectroscopy can be used for the structural analyses of antigen binding and also of domain-domain interactions in the antibody molecule.

Preliminary study on guiding therapy of subcutaneous human hetero graft in nude mice by 211-At labelled monoclonal antibody against gastric cancer

International Nuclear Information System (INIS)

Luo Lin; Wang Fangyuan

1993-01-01

In short time, 211 At labelled monoclonal antibody 3H 11 inhibited the growth of human gastric cancer grafted in nude mice effectively. The most evident inhibition was observed at the 9th day after treatment, and the tumor inhibition rates were 80%, 93%, 48% in the groups of intravenous injection, internal tumor injection (both 211 At-3H 11 5 μCi per animal), Na 211 At (5 μCi per animal) treatment respectively. On the 20th day, when animals were killed, the tumor inhibition rates were 66%, 81%, 6%, respectively. Inhibition treated with Na 211 At showed obviously lower than those at the 9th day

Measurement of cyclosporine concentrations in whole blood: HPLC and radioimmunoassay with a specific monoclonal antibody and 3H- or 125I-labeled ligand compared

International Nuclear Information System (INIS)

Wolf, B.A.; Daft, M.C.; Koenig, J.W.; Flye, M.W.; Turk, J.W.; Scott, M.G.

1989-01-01

We compared cyclosporine concentrations in whole blood as measured by HPLC and by RIA with a monoclonal antibody specific for cyclosporine with 3 H- or 125 I-labeled cyclosporine ligand. The 3 H-RIA kit slightly underestimated cyclosporine concentrations (greater than 600 micrograms/L) in comparison with HPLC. Over a wide range of concentrations, cyclosporine measured with the 125 I-RIA kit correlated well with HPLC (slope = 0.99, n = 301, r = 0.98), observed for samples from recipients of kidney, heart, or liver allografts (respective slopes: 1.01, 0.93, and 1.00). The 125 I-RIA standard curve was linear to 1000 micrograms of cyclosporine per liter. Inter- and intra-assay CVs for 125 I-RIA measurements of cyclosporine were less than or equal to 7%. Evidently, the 125 I-RIA kit involving a monoclonal antibody specific for cyclosporine is equivalent to the HPLC assay and can replace it for therapeutic drug monitoring of cyclosporine therapy

Application of the indirect enzyme-labeled antibody microtest to the detection and surveillance of animal diseases. [Brucellosis, cholera, and trichinosis in cattle and swine

Energy Technology Data Exchange (ETDEWEB)

Saunders, G.C. Clinard, E.H.; Bartlett, M.L.; Sanders, W.M.

1976-01-01

The rapid, indirect enzyme-labeled antibody (ELA) microplate test has been developed as a diagnostic and surveillance tool to aid in the control of animal disease. Data are presented, which illustrate the application of the test to viral (hog cholera), parasitic (trichinosis), and bacterial (brucellosis) diseases of animals. A greater than 95 percent correlation was observed between the hog cholera ELA test and the hog cholera serum neutralization test performed on over 2000 mixed hog cholera positive and negative field samples obtained during the 1976 New Jersey epizootic. Of 56 swine naturally infected with Trichinella spiralis at a level considered dangerous to man, all were ELA positive, while only one of 360 T. spiralis negative packing house sera was ELA positive. Preliminary experiments with bovine brucellosis (Brucella abortus) indicate that the ELA test is more sensitive than other test methods currently in use. ELA procedures should soon become tests of choice for the detection of antibodies to animal disease agents.

Microradioimmunoassay for antibodies to tumor-associated antigens

International Nuclear Information System (INIS)

Huang, J.C.C.; Berczi, I.; Froese, G.; Tsay, H.M.; Sehon, A.H.

1975-01-01

A versatile microradioimmunoassay for the detection of antibodies to tumor-associated and other tissue antigens was described. The method involved: the preparation of solid-phase antigen with cultured (already adhered) or noncultured cells (sedimented by centrifugation) fixed to Micro-Test plates with neutral buffered formaldehyde or absolute methanol; the incubation of the antigen with test or control sera; and the incubation of the antigen with radioiodinated antiglobulin antibody. The nonspecific background of radioactivity was reduced to an acceptable level by the fixed cells being precoated in the wells with 0.5 percent bovine serum albumin in phosphate-buffered saline which was also used for the dilution of sera and labeled antiglobulin antibody. Tumor cells in primary cultures gave a high background, as compared to long-term cultures, which was due to the presence of immunoglobulins (most likely tumor-specific antibody). The specific antibody response to a syngeneic mouse tumor was demonstrated by this technique. (auth)

Site-specific photoconjugation of antibodies using chemically synthesized IgG-binding domains.

Science.gov (United States)

Perols, Anna; Karlström, Amelie Eriksson

2014-03-19

Site-specific labeling of antibodies can be performed using the immunoglobulin-binding Z domain, derived from staphylococcal protein A (SpA), which has a well-characterized binding site in the Fc region of antibodies. By introducing a photoactivable probe in the Z domain, a covalent bond can be formed between the Z domain and the antibody by irradiation with UV light. The aim of this study was to improve the conjugation yield for labeling of different subclasses of IgG having different sequence composition, using a photoactivated Z domain variant. Four different variants of the Z domain (Z5BPA, Z5BBA, Z32BPA, and Z32BBA) were synthesized to investigate the influence of the position of the photoactivable probe and the presence of a flexible linker between the probe and the protein. For two of the variants, the photoreactive benzophenone group was introduced as part of an amino acid side chain by incorporation of the unnatural amino acid benzoylphenylalanine (BPA) during peptide synthesis. For the other two variants, the photoreactive benzophenone group was attached via a flexible linker by coupling of benzoylbenzoic acid (BBA) to the ε-amino group of a selectively deprotected lysine residue. Photoconjugation experiments using human IgG1, mouse IgG1, and mouse IgG2A demonstrated efficient conjugation for all antibodies. It was shown that differences in linker length had a large impact on the conjugation efficiency for labeling of mouse IgG1, whereas the positioning of the photoactivable probe in the sequence of the protein had a larger effect for mouse IgG2A. Conjugation to human IgG1 was only to a minor extent affected by position or linker length. For each subclass of antibody, the best variant tested using a standard conjugation protocol resulted in conjugation efficiencies of 41-66%, which corresponds to on average approximately one Z domain attached to each antibody. As a combination of the two best performing variants, Z5BBA and Z32BPA, a Z domain variant with

A simple assay for the detection of antibodies to endocrine islet cell surface antigens

International Nuclear Information System (INIS)

Contreas, G.; Madsen, O.D.; Vissing, H.; Lernmark, Aa.

1986-01-01

A simple and sensitive immunoradiometric assay for the detection of islet cell surface antibodies (CIRMA) has been developed. Live, transformed islet cells derived from a liver metastasis of a transplantable islet cell tumor were grown in removable microtiter wells and incubated with antibody. Cell-bound antibodies were quantitated using 125 I-labelled second antibodies. The assay was used to detect islet cell antibodies present in sera from non-diabetic and diabetic BB rats and proved to be particularly effective for screening hybridoma supernatants in order to identify monoclonal antibodies recognizing islet cell surface antigens. (Auth.)

Localized conformational interrogation of antibody and antibody-drug conjugates by site-specific carboxyl group footprinting.

Science.gov (United States)

Pan, Lucy Yan; Salas-Solano, Oscar; Valliere-Douglass, John F

Establishing and maintaining conformational integrity of monoclonal antibodies (mAbs) and antibody-drug conjugates (ADCs) during development and manufacturing is critical for ensuring their clinical efficacy. As presented here, we applied site-specific carboxyl group footprinting (CGF) for localized conformational interrogation of mAbs. The approach relies on covalent labeling that introduces glycine ethyl ester tags onto solvent-accessible side chains of protein carboxylates. Peptide mapping is used to monitor the labeling kinetics of carboxyl residues and the labeling kinetics reflects the conformation or solvent-accessibility of side chains. Our results for two case studies are shown here. The first study was aimed at defining the conformational changes of mAbs induced by deglycosylation. We found that two residues in C H 2 domain (D268 and E297) show significantly enhanced side chain accessibility upon deglycosylation. This site-specific result highlighted the advantage of monitoring the labeling kinetics at the amino acid level as opposed to the peptide level, which would result in averaging out of highly localized conformational differences. The second study was designed to assess conformational effects brought on by conjugation of mAbs with drug-linkers. All 59 monitored carboxyl residues displayed similar solvent-accessibility between the ADC and mAb under native conditions, which suggests the ADC and mAb share similar side chain conformation. The findings are well correlated and complementary with results from other assays. This work illustrated that site-specific CGF is capable of pinpointing local conformational changes in mAbs or ADCs that might arise during development and manufacturing. The methodology can be readily implemented within the industry to provide comprehensive conformational assessment of these molecules.

Radiometallating antibodies and autoantigenic peptides

International Nuclear Information System (INIS)

Mercer-Smith, J.A.; Lewis, D.; Cole, D.A.; Newmyer, S.L.; Schulte, L.D.; Mixon, P.L.; Schreyer, S.A.; Burns, T.P.; Roberts, J.C.; Figard, S.D.; McCormick, D.J.; Lennon, V.A.; Hayashi, M.; Lavallee, D.K.

1991-01-01

We have developed methods to radiolabel large molecules, using porphyrins as bifunctional chelating agents for radiometals. The porphyrins are substituted with an N- benzyl group to activate them for radiometallation under mild reaction conditions. Porphyrins that have one functional group for covalent attachment to other molecules cannot cause crosslinking. We have examined the labeling chemistry for antibodies and have developed methods to label smaller biologically active molecules, such as autoantigenic peptides (fragments of the acetylcholine receptor), which are pertinent to myasthenia gravis research. The methods of covalent attachment of these bifunctional chelating agents to large molecules, the radiometallation chemistry, and biological characterization of the radiolabeled compounds will be discussed

Near-infrared emitting fluorescent nanocrystals-labeled natural killer cells as a platform technology for the optical imaging of immunotherapeutic cells-based cancer therapy

International Nuclear Information System (INIS)

Lim, Yong Taik; Cho, Mi Young; Noh, Young-Woock; Chung, Bong Hyun; Chung, Jin Woong

2009-01-01

This study describes the development of near-infrared optical imaging technology for the monitoring of immunotherapeutic cell-based cancer therapy using natural killer (NK) cells labeled with fluorescent nanocrystals. Although NK cell-based immunotherapeutic strategies have drawn interest as potent preclinical or clinical methods of cancer therapy, there are few reports documenting the molecular imaging of NK cell-based cancer therapy, primarily due to the difficulty of labeling of NK cells with imaging probes. Human natural killer cells (NK92MI) were labeled with anti-human CD56 antibody-coated quantum dots (QD705) for fluorescence imaging. FACS analysis showed that the NK92MI cells labeled with anti-human CD56 antibody-coated QD705 have no effect on the cell viability. The effect of anti-human CD56 antibody-coated QD705 labeling on the NK92MI cell function was investigated by measuring interferon gamma (IFN- γ) production and cytolytic activity. Finally, the NK92MI cells labeled with anti-human CD56 antibody-coated QD705 showed a therapeutic effect similar to that of unlabeled NK92MI cells. Images of intratumorally injected NK92MI cells labeled with anti-human CD56 antibody-coated could be acquired using near-infrared optical imaging both in vivo and in vitro. This result demonstrates that the immunotherapeutic cells labeled with fluorescent nanocrystals can be a versatile platform for the effective tracking of injected therapeutic cells using optical imaging technology, which is very important in cell-based cancer therapies.

Pharmacokinetics and normal organ dosimetry following intraperitoneal rhenium-186-labeled monoclonal antibody

International Nuclear Information System (INIS)

Breitz, H.B.; Durham, J.S.; Fisher, D.R.

1995-01-01

Pharmacokinetics, biodistribution and radiation dose estimates following intraperitoneal administration of a 186 Re-labeled murine antibody, NR-LU-10, were assessed in 27 patients with advanced ovarian cancer. Quantitative gamma camera imaging and gamma counting of serum and intraperitoneal fluid radioactivity were used to obtain data for dosimetry estimation. The MIRD intraperitoneal model was used to estimate dose to normal organs from radioactivity within the peritoneal cavity. The absorbed dose to normal peritoneum was estimated in two ways: from the gamma camera activity and peritoneal fluid samples. Serum activity peaked at 44 hr and depended on the concentration of radioactivity in the peritoneal fluid. Mean cumulative urinary excretion of 186 Re was 50% by 140 hr. Estimates of radiation absorbed dose to normal organs in rad/mCi administered (mean ± s.d.) were whole body 0.7 ± 0.3; marrow 0.4 ±0.1; liver 1.9 ±0.9; lungs 1.3 ± 0.7; kidneys 0.2 ± 0.2; intestine 0.2 ±0.2. Peritoneal surface dose estimates varied depending on the volume of fluid infused and the method of dose determination. Using gamma camera data, the peritoneal dose ranged for 7 to 36 rad/mCi. Using peritoneal fluid sample data, the dose ranged from 2 to 25 rad/mCi. Significant myelosuppression was observed at marrow doses above 100 rad. Noninvasive methods of dose estimation for intraperitoneal administration of radioimmunoconjugates provide reasonable estimates when compared with previously described methods. 31 refs., 6 figs., 2 tabs

A novel immuno-gold labeling protocol for nanobody-based detection of HER2 in breast cancer cells using immuno-electron microscopy.

Science.gov (United States)

Kijanka, M; van Donselaar, E G; Müller, W H; Dorresteijn, B; Popov-Čeleketić, D; El Khattabi, M; Verrips, C T; van Bergen En Henegouwen, P M P; Post, J A

2017-07-01

Immuno-electron microscopy is commonly performed with the use of antibodies. In the last decade the antibody fragment indicated as nanobody (VHH or single domain antibody) has found its way to different applications previously done with conventional antibodies. Nanobodies can be selected to bind with high affinity and specificity to different antigens. They are small (molecular weight ca. 15kDa) and are usually easy to produce in microorganisms. Here we have evaluated the feasibility of a nanobody binding to HER2 for application in immuno-electron microscopy. To obtain highest labeling efficiency combined with optimal specificity, different labeling conditions were analysed, which included nanobody concentration, fixation and blocking conditions. The obtained optimal protocol was applied for post-embedment labeling of Tokuyasu cryosections and for pre-embedment labeling of HER2 for fluorescence microscopy and both transmission and scanning electron microscopy. We show that formaldehyde fixation after incubation with the anti-HER2 nanobody, improves labeling intensity. Among all tested blocking agents the best results were obtained with a mixture of cold water fish gelatine and acetylated bovine serum albumin, which prevented a-specific interactions causing background labeling while preserving specific interactions at the same time. In conclusion, we have developed a nanobody-based protocol for immuno-gold labeling of HER2 for Tokuyasu cryosections in TEM as well as for pre-embedment gold labeling of cells for both TEM and SEM. Copyright © 2017. Published by Elsevier Inc.