A single-domain antibody-linked Fab bispecific antibody Her2-S-Fab has potent cytotoxicity against Her2-expressing tumor cells.

Science.gov (United States)

Li, Aifen; Xing, Jieyu; Li, Li; Zhou, Changhua; Dong, Bin; He, Ping; Li, Qing; Wang, Zhong

2016-12-01

Her2, which is frequently overexpressed in breast cancer, is one of the most studied tumor-associated antigens for cancer therapy. Anti-HER2 monoclonal antibody, trastuzumab, has achieved significant clinical benefits in metastatic breast cancer. In this study, we describe a novel bispecific antibody Her2-S-Fab targeting Her2 by linking a single domain anti-CD16 VHH to the trastuzumab Fab. The Her2-S-Fab antibody can be efficiently expressed and purified from Escherichia coli, and drive potent cancer cell killing in HER2-overexpressing cancer cells. In xenograft model, the Her2-S-Fab suppresses tumor growth in the presence of human immune cells. Our results suggest that the bispecific Her2-S-Fab may provide a valid alternative to Her2 positive cancer therapy.

Development of cell-penetrating bispecific antibodies targeting the N-terminal domain of androgen receptor for prostate cancer therapy.

Science.gov (United States)

Goicochea, Nancy L; Garnovskaya, Maria; Blanton, Mary G; Chan, Grace; Weisbart, Richard; Lilly, Michael B

2017-12-01

Castration-resistant prostate cancer cells exhibit continued androgen receptor signaling in spite of low levels of ligand. Current therapies to block androgen receptor signaling act by inhibiting ligand production or binding. We developed bispecific antibodies capable of penetrating cells and binding androgen receptor outside of the ligand-binding domain. Half of the bispecific antibody molecule consists of a single-chain variable fragment of 3E10, an anti-DNA antibody that enters cells. The other half is a single-chain variable fragment version of AR441, an anti-AR antibody. The resulting 3E10-AR441 bispecific antibody enters human LNCaP prostate cells and accumulates in the nucleus. The antibody binds to wild-type, mutant and splice variant androgen receptor. Binding affinity of 3E10-AR441 to androgen receptor (284 nM) was lower than that of the parental AR441 mAb (4.6 nM), but could be improved (45 nM) through alternative placement of the affinity tags, and ordering of the VH and VK domains. The 3E10-AR441 bispecific antibody blocked genomic signaling by wild-type or splice variant androgen receptor in LNCaP cells. It also blocked non-genomic signaling by the wild-type receptor. Furthermore, bispecific antibody inhibited the growth of C4-2 prostate cancer cells under androgen-stimulated conditions. The 3E10-AR441 biAb can enter prostate cancer cells and inhibits androgen receptor function in a ligand-independent manner. It may be an attractive prototype agent for prostate cancer therapy. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Bispecific antibodies and their use in applied research

Directory of Open Access Journals (Sweden)

Harshit Verma

Full Text Available Bispecific antibodies (BsAb can, by virtue of combining two binding specificities, improve the selectivity and efficacy of antibody-based treatment of human disease. Antibodies with two distinct binding specificities have great potential for a wide range of clinical applications as targeting agents for in vitro and in vivo immunodiagnosis, therapy and for improving immunoassays. They have shown great promise for targeting cytotoxic effector cells, delivering radionuclides, toxins or cytotoxic drugs to specific targets, particularly tumour cells. The development of BsAb research goes through three main stages: chemical cross linking of murine-derived monoclonal antibody, hybrid hybridomas and engineered BsAb. This article is providing the potential applications of bispecific antibodies. [Vet World 2012; 5(12.000: 775-780

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.

A pharmacology guided approach for setting limits on product-related impurities for bispecific antibody manufacturing.

Science.gov (United States)

Rajan, Sharmila; Sonoda, Junichiro; Tully, Timothy; Williams, Ambrose J; Yang, Feng; Macchi, Frank; Hudson, Terry; Chen, Mark Z; Liu, Shannon; Valle, Nicole; Cowan, Kyra; Gelzleichter, Thomas

2018-04-13

bFKB1 is a humanized bispecific IgG1 antibody, created by conjoining an anti-Fibroblast Growth Factor Receptor 1 (FGFR1) half-antibody to an anti-Klothoβ (KLB) half-antibody, using the knobs-into-holes strategy. bFKB1 acts as a highly selective agonist for the FGFR1/KLB receptor complex and is intended to ameliorate obesity-associated metabolic defects by mimicking the activity of the hormone FGF21. An important aspect of the biologics product manufacturing process is to establish meaningful product specifications regarding the tolerable levels of impurities that copurify with the drug product. The aim of the current study was to determine acceptable levels of product-related impurities for bFKB1. To determine the tolerable levels of these impurities, we dosed obese mice with bFKB1 enriched with various levels of either HMW impurities or anti-FGFR1-related impurities, and measured biomarkers for KLB-independent FGFR1 signaling. Here, we show that product-related impurities of bFKB1, in particular, high molecular weight (HMW) impurities and anti-FGFR1-related impurities, when purposefully enriched, stimulate FGFR1 in a KLB-independent manner. By taking this approach, the tolerable levels of product-related impurities were successfully determined. Our study demonstrates a general pharmacology-guided approach to setting a product specification for a bispecific antibody whose homomultimer-related impurities could lead to undesired biological effects. Copyright © 2018. Published by Elsevier Inc.

The future of antibody therapeutics: ADCs bi-specifics and RIT

International Nuclear Information System (INIS)

Reichert, J.

2015-01-01

Full text of publication follows. Antibodies are widely accepted as remarkably versatile therapeutic agents. As evidence of this, the ∼ 30 antibody products marketed worldwide had total global sales of more than 50 billion dollars in 2012, and the commercial clinical pipeline currently comprises over 350 antibody-based product candidates. In a testament to scientific ingenuity, the investigational molecules (clinical and preclinical) are notably diverse in their composition of matter and include antibodies conjugated to a variety of agents (drugs, radioisotopes), bi-specific antibodies, and fragments or domains of antibodies. The concepts that form the basis of these agents were established decades ago, but advances in technology are now allowing new opportunities for their development. In this presentation, future directions in antibody therapeutics development will be discussed, with a focus on antibody-drug conjugates, bi-specific antibodies and radioimmunotherapy. (author)

A "Trojan horse" bispecific-antibody strategy for broad protection against ebolaviruses.

Science.gov (United States)

Wec, Anna Z; Nyakatura, Elisabeth K; Herbert, Andrew S; Howell, Katie A; Holtsberg, Frederick W; Bakken, Russell R; Mittler, Eva; Christin, John R; Shulenin, Sergey; Jangra, Rohit K; Bharrhan, Sushma; Kuehne, Ana I; Bornholdt, Zachary A; Flyak, Andrew I; Saphire, Erica Ollmann; Crowe, James E; Aman, M Javad; Dye, John M; Lai, Jonathan R; Chandran, Kartik

2016-10-21

There is an urgent need for monoclonal antibody (mAb) therapies that broadly protect against Ebola virus and other filoviruses. The conserved, essential interaction between the filovirus glycoprotein, GP, and its entry receptor Niemann-Pick C1 (NPC1) provides an attractive target for such mAbs but is shielded by multiple mechanisms, including physical sequestration in late endosomes. Here, we describe a bispecific-antibody strategy to target this interaction, in which mAbs specific for NPC1 or the GP receptor-binding site are coupled to a mAb against a conserved, surface-exposed GP epitope. Bispecific antibodies, but not parent mAbs, neutralized all known ebolaviruses by coopting viral particles themselves for endosomal delivery and conferred postexposure protection against multiple ebolaviruses in mice. Such "Trojan horse" bispecific antibodies have potential as broad antifilovirus immunotherapeutics. Copyright © 2016, American Association for the Advancement of Science.

In vivo localization of radiolabeled monoclonal antibody to carcinoembryonic antigen (CEA) in a CEA-producing tumor

International Nuclear Information System (INIS)

Kamei, Tetsuya; Seto, Hikaru; Taki, Kuniyasu; Soya, Toshio; Kakishita, Masao; Maeda, Masatoshi; Honda, Takashi; Koshimura, Saburou.

1987-01-01

To compare accumulation of the 125 I-labeled antibodies(anti-carcinoembryonic antigen(CEA) monoclonal antibody and polyclonal antibody) to a CEA-producing tumor (SC-2-JCK), an in vivo localization study was performed in nude mice. The tumor-to-blood ratio at 120 hours after injection rose to 4.6 for the monoclonal antibody, but remained at 1.3 for the polyclonal antibody. However, no differences were noted between the antibodies up to 72 hours after injection. In autoradiograms, selective accumulation of the tracer was noted in the tumor for both antibodies. However, no superiority or inferiority of imaging for either of the antibodies could be definitely determined. (author)

The importance of tumor marker titers for the indication of immunoscintigraphy with monoclonal antibodies anti-CEA and anti-CA 19.9

International Nuclear Information System (INIS)

Bouvier, J.F.; Charrie, A.; Fleury-Goyon, M.C.; Chauvot, P. et; Lahneche, B.E.

1986-01-01

In 18 patients operated for malignant tumors 20 immunoscintigraphies were done with a monoclonal antibody cocktail (anti-CEA F(ab') 2 and anti-CA 19.9 F(ab') 2 ). Immediately before scintigraphy tumor marker titers in plasma were determined in all cases. Tumor marker levels corresponding to positive or doubtful scintigraphies are analysed. (Author)

Bispecific small molecule-antibody conjugate targeting prostate cancer.

Science.gov (United States)

Kim, Chan Hyuk; Axup, Jun Y; Lawson, Brian R; Yun, Hwayoung; Tardif, Virginie; Choi, Sei Hyun; Zhou, Quan; Dubrovska, Anna; Biroc, Sandra L; Marsden, Robin; Pinstaff, Jason; Smider, Vaughn V; Schultz, Peter G

2013-10-29

Bispecific antibodies, which simultaneously target CD3 on T cells and tumor-associated antigens to recruit cytotoxic T cells to cancer cells, are a promising new approach to the treatment of hormone-refractory prostate cancer. Here we report a site-specific, semisynthetic method for the production of bispecific antibody-like therapeutics in which a derivative of the prostate-specific membrane antigen-binding small molecule DUPA was selectively conjugated to a mutant αCD3 Fab containing the unnatural amino acid, p-acetylphenylalanine, at a defined site. Homogeneous conjugates were generated in excellent yields and had good solubility. The efficacy of the conjugate was optimized by modifying the linker structure, relative binding orientation, and stoichiometry of the ligand. The optimized conjugate showed potent and selective in vitro activity (EC50 ~ 100 pM), good serum half-life, and potent in vivo activity in prophylactic and treatment xenograft mouse models. This semisynthetic approach is likely to be applicable to the generation of additional bispecific agents using drug-like ligands selective for other cell-surface receptors.

Bispecific small molecule–antibody conjugate targeting prostate cancer

Science.gov (United States)

Kim, Chan Hyuk; Axup, Jun Y.; Lawson, Brian R.; Yun, Hwayoung; Tardif, Virginie; Choi, Sei Hyun; Zhou, Quan; Dubrovska, Anna; Biroc, Sandra L.; Marsden, Robin; Pinstaff, Jason; Smider, Vaughn V.; Schultz, Peter G.

2013-01-01

Bispecific antibodies, which simultaneously target CD3 on T cells and tumor-associated antigens to recruit cytotoxic T cells to cancer cells, are a promising new approach to the treatment of hormone-refractory prostate cancer. Here we report a site-specific, semisynthetic method for the production of bispecific antibody-like therapeutics in which a derivative of the prostate-specific membrane antigen-binding small molecule DUPA was selectively conjugated to a mutant αCD3 Fab containing the unnatural amino acid, p-acetylphenylalanine, at a defined site. Homogeneous conjugates were generated in excellent yields and had good solubility. The efficacy of the conjugate was optimized by modifying the linker structure, relative binding orientation, and stoichiometry of the ligand. The optimized conjugate showed potent and selective in vitro activity (EC50 ∼100 pM), good serum half-life, and potent in vivo activity in prophylactic and treatment xenograft mouse models. This semisynthetic approach is likely to be applicable to the generation of additional bispecific agents using drug-like ligands selective for other cell-surface receptors. PMID:24127589

Uptake of radiolabeled anti-CEA antibodies in human colorectal primary tumors as a function of tumor mass

International Nuclear Information System (INIS)

Williams, L.E.; Bares, R.B.; Buell, U.; Fass, J.; Schumpelick, V.; Hauptmann, S.

1993-01-01

An inverse correlation has been demonstrated between tumor uptake (u, in units of % injected dose/kg) of monoclonal antibody (Mab) and tumor mass (m, in units of g) for colorectal carcinoma in a series of 19 consecutive patients. The correlation (ρ=-0.510), developed using surgical samples was of the form u=ab b and was significant at the 2% level of confidence. All tumors were positive for carcinoembryonic antigen (CEA) and the radiopharmaceutical was in iodine-131 labeled anti-CEA Mab. Such correlations have been predicted earlier from murine and rat tumor uptake data. The slope parameter (b) was -0.362, a number consistent with the previous value (-0.382) found in anti-CEA experiments in mice bearing human xenograft LS174T tumors. (orig.)

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.

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

REDUCTION OF EGP-2-POSITIVE PULMONARY METASTASES BY BISPECIFIC-ANTIBODY-REDIRECTED T-CELLS IN AN IMMUNOCOMPETENT RAT MODEL

NARCIS (Netherlands)

KROESEN, BJ; HELFRICH, W; BAKKER, A; WUBBENA, AS; BAKKER, H; KAL, HB; THE, TH; DELEIJ, L

1995-01-01

Effectiveness of bispecific-monoclonal-antibody (B5MAb)-mediated cellular anti-tumour activity was evaluated in vitro and in vivo in relation to the additional need for T-cell activation in a new immunocompetent rat tumour model. L37 tumour cells, derived from a squamous-cell carcinoma of the lung

Biodistribution and tumor imaging of an anti-CEA single-chain antibody-albumin fusion protein

International Nuclear Information System (INIS)

Yazaki, Paul J.; Kassa, Thewodros; Cheung, Chia-wei; Crow, Desiree M.; Sherman, Mark A.; Bading, James R.; Anderson, Anne-Line J.; Colcher, David; Raubitschek, Andrew

2008-01-01

Albumin fusion proteins have demonstrated the ability to prolong the in vivo half-life of small therapeutic proteins/peptides in the circulation and thereby potentially increase their therapeutic efficacy. To evaluate if this format can be employed for antibody-based imaging, an anticarcinoembryonic antigen (CEA) single-chain antibody(scFv)-albumin fusion protein was designed, expressed and radiolabeled for biodistribution and imaging studies in athymic mice bearing human colorectal carcinoma LS-174T xenografts. The [ 125 I]-T84.66 fusion protein demonstrated rapid tumor uptake of 12.3% injected dose per gram (ID/g) at 4 h that reached a plateau of 22.7% ID/g by 18 h. This was a dramatic increase in tumor uptake compared to 4.9% ID/g for the scFv alone. The radiometal [ 111 In]-labeled version resulted in higher tumor uptake, 37.2% ID/g at 18 h, which persisted at the tumor site with tumor: blood ratios reaching 18:1 and with normal tissues showing limited uptake. Based on these favorable imaging properties, a pilot [ 64 Cu]-positron emission tomography imaging study was performed with promising results. The anti-CEA T84.66 scFv-albumin fusion protein demonstrates highly specific tumor uptake that is comparable to cognate recombinant antibody fragments. The radiometal-labeled version, which shows lower normal tissue accumulation than these recombinant antibodies, provides a promising and novel platform for antibody-based imaging agents

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)

Fully human IgG and IgM antibodies directed against the carcinoembryonic antigen (CEA Gold 4 epitope and designed for radioimmunotherapy (RIT of colorectal cancers

Directory of Open Access Journals (Sweden)

Pugnière Martine

2004-10-01

VG-IgM biodistribution was not possible in this mouse model in which IgM displays a very short half-life due to poly-Ig receptor expression in the liver. Conclusion Our human anti-CEA IgG2κ is a promising candidate for radioimmunotherapy in intact form, as F(ab'2 fragments, or as a bispecific antibody.

Kinetics of anti-carcinoembryonic antigen antibody internalization: effects of affinity, bivalency, and stability

Science.gov (United States)

Schmidt, Michael M.; Thurber, Greg M.

2010-01-01

Theoretical analyses suggest that the cellular internalization and catabolism of bound antibodies contribute significantly to poor penetration into tumors. Here we quantitatively assess the internalization of antibodies and antibody fragments against the commonly targeted antigen carcinoembryonic antigen (CEA). Although CEA is often referred to as a non-internalizing or shed antigen, anti-CEA antibodies and antibody fragments are shown to be slowly endocytosed by LS174T cells with a half-time of 10–16 h, a time scale consistent with the metabolic turnover rate of CEA in the absence of antibody. Anti-CEA single chain variable fragments (scFvs) with significant differences in affinity, stability against protease digestion, and valency exhibit similar uptake rates of bound antibody. In contrast, one anti-CEA IgG exhibits unique binding and trafficking properties with twice as many molecules bound per cell at saturation and significantly faster cellular internalization after binding. The internalization rates measured herein can be used in simple computational models to predict the microdistribution of these antibodies in tumor spheroids. PMID:18408925

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

Science.gov (United States)

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.

In vitro and in vivo comparison of binding of 99m-Tc-labeled anti-CEA MAb F33-104 with 99m-Tc-labeled anti-CEA MAb BW431/26

International Nuclear Information System (INIS)

Watanabe, N.; Gunma Univ. School of Medicine; Oriuchi, N.; Inoue, T.; Sugiyama, S.; Kuroki, M.; Matsuoka, Y.; Tanada, S.; Murata, H.; Sasaki, Y.

1999-01-01

Aim: The purpose of this study was to assess the potential for radioimmunodetection (RAID) of murine anti-carcinoembryonic antigen (CEA) monoclonal antibody (MAb) F33-104 labeled with technetium-99m (99m-Tc) by a reduction-mediated labeling method. Methods: The binding capacity of 99m-Tc-labeled anti-CEA MAb F33-104 with CEA by means of in vitro procedures such as immunoradiometric assay and cell binding assay and the biodistribution of 99m-Tc-labeled anti-CEA MAb F33-104 in normal nude mice and nude mice bearing human colon adenocarcinoma LS180 tumor were investigated and compared with 99m-Tc-labeled anti-CEA MAb BW431/26. Results: The in vitro binding rate of 99m-Tc-labeled anti-CEA MAb F33-104 with CEA in solution and attached to the cell membrane was significantly higher than 99m-Tc-labeled anti-CEA MAb BW431/261 (31.4 ± 0.95% vs. 11.9 ± 0.55% at 100 ng/mL of soluble CEA, 83.5 ± 2.84% vs. 54.0 ± 2.54% at 10 7 of LS 180 cells). In vivo, accumulation of 99m-Tc-labeled anti-CEA MAb F33-104 was higher at 18 h postinjection than 99m-Tc-labeled anti-CEA MAb BW431/26 (20.1 ± 3.50% ID/g vs. 14.4 ± 3.30% ID/g). 99m-Tc-activity in the kidneys of nude mice bearing tumor was higher at 18 h postinjection than at 3 h (12.8 ± 2.10% ID/g vs. 8.01 ± 2.40% ID/g of 99m-Tc-labeled anti-CEA MAb F33-104, 10.7 ± 1.70% ID/g vs. 8.10 ± 1.75% ID/g of 99m-Tc-labeled anti-CEA MAb BW431/26). Conclusion: 99m-Tc-labeled anti-CEA MAb F33-104 is a potential novel agent for RAID of recurrent colorectal cancer. (orig.) [de

Bivalent fragment of the ior-CEA1 antibody. A challenge to the positive CEA tumors radioimmunotherapy

International Nuclear Information System (INIS)

Ravelo, Rolando; Sanchez, Iradia; Pimentel, Gilmara; Oliva, Juan; Perez, Lincidio; Ayala, Marta; Bell, Hansell; Gavilondo, Jorge

2006-01-01

The directed radiotherapy of the solid tumors with fragments recombinants of radiolabelled antibodies is a topic of current investigation, so much at preclinical level as clinical. This work describes the preclinical characterization of a new fragment type diabody of the AcMo ior CEA1 that has been labelled with 131 I for their use in the diagnosis and the therapy of CEA positive tumors. The radiolabelling methodology used allows the incorporation of more than 90% of the radio iodine to the molecule without committing the capacity of recognition of its antigen significantly. The combination of the favourable properties pharmacy kinetic and high selective accumulation in the tumor, they make of the diabody anti CEA an appropriate candidate for the radioimmunodiagnosis and the radioimmunotherapy of tumors that expresses CEA (Author)

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

Addressing safety liabilities of TfR bispecific antibodies that cross the blood-brain barrier.

Science.gov (United States)

Couch, Jessica A; Yu, Y Joy; Zhang, Yin; Tarrant, Jacqueline M; Fuji, Reina N; Meilandt, William J; Solanoy, Hilda; Tong, Raymond K; Hoyte, Kwame; Luk, Wilman; Lu, Yanmei; Gadkar, Kapil; Prabhu, Saileta; Ordonia, Benjamin A; Nguyen, Quyen; Lin, Yuwen; Lin, Zhonghua; Balazs, Mercedesz; Scearce-Levie, Kimberly; Ernst, James A; Dennis, Mark S; Watts, Ryan J

2013-05-01

Bispecific antibodies using the transferrin receptor (TfR) have shown promise for boosting antibody uptake in brain. Nevertheless, there are limited data on the therapeutic properties including safety liabilities that will enable successful development of TfR-based therapeutics. We evaluate TfR/BACE1 bispecific antibody variants in mouse and show that reducing TfR binding affinity improves not only brain uptake but also peripheral exposure and the safety profile of these antibodies. We identify and seek to address liabilities of targeting TfR with antibodies, namely, acute clinical signs and decreased circulating reticulocytes observed after dosing. By eliminating Fc effector function, we ameliorated the acute clinical signs and partially rescued a reduction in reticulocytes. Furthermore, we show that complement mediates a residual decrease in reticulocytes observed after Fc effector function is eliminated. These data raise important safety concerns and potential mitigation strategies for the development of TfR-based therapies that are designed to cross the blood-brain barrier.

Immunity War: A Novel Therapy for Lymphoma Using T-cell Bispecific Antibodies.

Science.gov (United States)

Prakash, Ajay; Diefenbach, Catherine S

2018-06-08

The activity of T cell mediated immunotherapies in B cell lymphoma has been limited to date. The novel bi-specific antibody CD20-TCB, has a 2:1 antibody design to maximize T cell engagement, and demonstrates activity in preclinical models. This may represent a novel therapeutic approach for patients with relapsed/refractory NHL. Copyright ©2018, American Association for Cancer Research.

Anti-CEA loaded maghemite nanoparticles as a theragnostic device for colorectal cancer

Directory of Open Access Journals (Sweden)

Campos da Paz M

2012-10-01

is highly specific for CEA-expressing cells. Finally, transmission electron microscopy analyses show that the association with anti-CEA seems to increase the number of LS174T cells with internalized maghemite nanoparticles, whereas no such increase seems to occur in the HCT116 cell line. In conclusion, the MF-anti-CEA sample is a biocompatible device that can specifically target CEA, suggesting its potential use as a theragnostic tool for CEA-expressing tumors, micrometastasis, and cancer-circulating cells.Keywords: magnetic nanoparticles, anti-CEA antibody, targeted delivery, diagnostic, Raman, biocompatible device

Anti-factor IXa/X bispecific antibody ACE910 prevents joint bleeds in a long-term primate model of acquired hemophilia A

Science.gov (United States)

Yoshihashi, Kazutaka; Takeda, Minako; Kitazawa, Takehisa; Soeda, Tetsuhiro; Igawa, Tomoyuki; Sampei, Zenjiro; Kuramochi, Taichi; Sakamoto, Akihisa; Haraya, Kenta; Adachi, Kenji; Kawabe, Yoshiki; Nogami, Keiji; Shima, Midori; Hattori, Kunihiro

2014-01-01

ACE910 is a humanized anti-factor IXa/X bispecific antibody mimicking the function of factor VIII (FVIII). We previously demonstrated in nonhuman primates that a single IV dose of ACE910 exerted hemostatic activity against hemophilic bleeds artificially induced in muscles and subcutis, and that a subcutaneous (SC) dose of ACE910 showed a 3-week half-life and nearly 100% bioavailability, offering support for effective prophylaxis for hemophilia A by user-friendly SC dosing. However, there was no direct evidence that such SC dosing of ACE910 would prevent spontaneous bleeds occurring in daily life. In this study, we newly established a long-term primate model of acquired hemophilia A by multiple IV injections of an anti-primate FVIII neutralizing antibody engineered in mouse-monkey chimeric form to reduce its antigenicity. The monkeys in the control group exhibited various spontaneous bleeding symptoms as well as continuous prolongation of activated partial thromboplastin time; notably, all exhibited joint bleeds, which are a hallmark of hemophilia. Weekly SC doses of ACE910 (initial 3.97 mg/kg followed by 1 mg/kg) significantly prevented these bleeding symptoms; notably, no joint bleeding symptoms were observed. ACE910 is expected to prevent spontaneous bleeds and joint damage in hemophilia A patients even with weekly SC dosing, although appropriate clinical investigation is required. PMID:25274508

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)

A Preclinical Population Pharmacokinetic Model for Anti-CD20/CD3 T-Cell-Dependent Bispecific Antibodies.

Science.gov (United States)

Ferl, Gregory Z; Reyes, Arthur; Sun, Liping L; Cheu, Melissa; Oldendorp, Amy; Ramanujan, Saroja; Stefanich, Eric G

2018-05-01

CD20 is a cell-surface receptor expressed by healthy and neoplastic B cells and is a well-established target for biologics used to treat B-cell malignancies. Pharmacokinetic (PK) and pharmacodynamic (PD) data for the anti-CD20/CD3 T-cell-dependent bispecific antibody BTCT4465A were collected in transgenic mouse and nonhuman primate (NHP) studies. Pronounced nonlinearity in drug elimination was observed in the murine studies, and time-varying, nonlinear PK was observed in NHPs, where three empirical drug elimination terms were identified using a mixed-effects modeling approach: i) a constant nonsaturable linear clearance term (7 mL/day/kg); ii) a rapidly decaying time-varying, linear clearance term (t ½  = 1.6 h); and iii) a slowly decaying time-varying, nonlinear clearance term (t ½  = 4.8 days). The two time-varying drug elimination terms approximately track with time scales of B-cell depletion and T-cell migration/expansion within the central blood compartment. The mixed-effects NHP model was scaled to human and prospective clinical simulations were generated. © 2018 The Authors. Clinical and Translational Science published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.

Isolation of scFv antibody fragments against HER2 and CEA tumor antigens from combinatorial antibody libraries derived from cancer patients.

Science.gov (United States)

Ayat, Hoda; Burrone, Oscar R; Sadghizadeh, Majid; Jahanzad, Eissa; Rastgou, Nasrin; Moghadasi, Sarrira; Arbabi, Mehdi

2013-11-01

Tumor cells expressing HER-2/neu and CEA antigens are potentially ideal targets for antibody-targeted therapy. In this study, two large human combinatorial libraries have been generated from the lymph nodes of breast cancer patients that express HER2 and CEA antigens in their tumors. These 'immune' libraries have been constructed in two different formats of scFv, differing in the length of the peptide linker connecting the two variable VH and VL domains. Libraries derived from these patients may contain a larger pool of anti-tumor antigen antibodies and are useful repertoire for isolating scFvs against any tumor markers. The results of this study showed that we were successful in obtaining human scFvs against HER-2/neu and CEA. For HER-2, cell-panning strategy was performed and resulted in two scFv binders that detected the complete HER-2 receptor on the cell membrane and internalized to the cells. Also, preliminary ELISA data showed that several anti-CEA scFv binders were isolated by panning. Copyright © 2013 The International Alliance for Biological Standardization. All rights reserved.

A new type of natural bispecific antibody with potential protective effect in Hashimoto thyroiditis.

Science.gov (United States)

Li, Wenli; Fan, Gaowei; Chen, Lida; Zhang, Rui; Zhang, Kuo; Sun, Yu; Lin, Guigao; Xie, Jiehong; Wang, Lunan; Li, Jinming

2014-09-01

As a new antibody concept, natural bispecific antibodies (nBsAbs) have been detected in long-term passive immunization and some diseases, but their potential immunomodulatory role remains unclear. Hashimoto thyroiditis (HT) appears to fulfill the condition for nBsAb production but has not yet been characterized. The objective of the study was to identify a new nBsAb against thyroid peroxidase (TPO) and thyroglobulin (Tg) in HT patients and to preliminarily explore its immunomodulatory role. Serum samples were obtained from 136 HT patients, 92 diseased controls, and 99 healthy controls for anti-TPO/Tg nBsAb detection. The relationship between anti-TPO/Tg nBsAb and other clinical parameters was also analyzed. The anti-TPO/Tg nBsAb was detected using a double-antigen sandwich ELISA. Higher nBsAb levels were found to be associated with decreased inflammation in HT patients. The prevalence of anti-TPO/Tg nBsAb in HT was 44.9% (61 of 136), significantly higher than that of diseased controls (2.2%, 2 of 92) (P thyroiditis patients. A new type of nBsAb against TPO and Tg in HT patients is identified. Our data also indicate a protective effect of anti-TPO/Tg nBsAb in the pathogenesis of HT and extend prior knowledge about nBsAb in diseases.

Role of immunoscintigraphy using Tc-99 m labelled monoclonal anti-CEA antibodies in the detection of Colorectal-rectal carcinoma

Energy Technology Data Exchange (ETDEWEB)

Ziada, G; Moustafa, H; Elhaddad, Sh; Elasser, M [Center of oncology and nuclear medicine of Kasr El-Eini Hospital, Cairo university, (Egypt)

1995-10-01

Twelve patients with colorectal carcinoma confirmed histopathologically and associated with high serum CEA level and underwent preoperative immunoscintigraphy (planar and SPECT projections) followed by operative resection with able to detect the primary tumor in colorectal region with 100% sensitivity, specificity and accuracy. Immunoscintigraphy showed sensitivity of 85%, specificity of 60% and accuracy of 66.6% in detection of para-aortic lymph nodes involved, as compared to 0%, 25% and 25% in abdominal sonography respectively. Concerning the liver involvement, there was higher sensitivity of 100% and accuracy of 91% of immunoscintigraphy in comparison to 50% and 66.6% abdominal sonography respectively. Imaging procedure at 4 and 24 hors postinjection with planar and SPECT studies were useful for proper localization of involved sites and to differentiate between malignant and benign lesions. Immunoscintigraphy is a safe procedure and the preparation of the kit of monoclonal anti-CEA anti-body is rapid with labelling efficiency more than 95% and with no adverse reaction. 3 figs.,2 tabs.

Role of immunoscintigraphy using Tc-99 m labelled monoclonal anti-CEA antibodies in the detection of Colorectal-rectal carcinoma

International Nuclear Information System (INIS)

Ziada, G.; Moustafa, H.; Elhaddad, Sh.; Elasser, M.

1995-01-01

Twelve patients with colorectal carcinoma confirmed histopathologically and associated with high serum CEA level and underwent preoperative immunoscintigraphy (planar and SPECT projections) followed by operative resection with able to detect the primary tumor in colorectal region with 100% sensitivity, specificity and accuracy. Immunoscintigraphy showed sensitivity of 85%, specificity of 60% and accuracy of 66.6% in detection of para-aortic lymph nodes involved, as compared to 0%, 25% and 25% in abdominal sonography respectively. Concerning the liver involvement, there was higher sensitivity of 100% and accuracy of 91% of immunoscintigraphy in comparison to 50% and 66.6% abdominal sonography respectively. Imaging procedure at 4 and 24 hors postinjection with planar and SPECT studies were useful for proper localization of involved sites and to differentiate between malignant and benign lesions. Immunoscintigraphy is a safe procedure and the preparation of the kit of monoclonal anti-CEA anti-body is rapid with labelling efficiency more than 95% and with no adverse reaction. 3 figs.,2 tabs

ATTACK, a novel bispecific T cell-recruiting antibody with trivalent EGFR binding and monovalent CD3 binding for cancer immunotherapy

DEFF Research Database (Denmark)

Harwood, Seandean Lykke; Alvarez-Cienfuegos, Ana; Alanes, Natalia Nuñez del Prado

2018-01-01

The redirection of T cell activity using bispecific antibodies is one of the most promising cancer immunotherapy approaches currently in development, but it is limited by cytokine storm-related toxicities, as well as the pharmacokinetics and tumor-penetrating capabilities of current bispecific an...

Pretargeting of human mammary carcinoma xenografts with bispecific anti-MUC1/anti-Ga chelate antibodies and immunoscintigraphy with PET

International Nuclear Information System (INIS)

Schuhmacher, Jochen; Klivenyi, Gabor; Kaul, Sepp; Henze, Marcus; Matys, Ronald; Hauser, Harald; Clorius, John

2001-01-01

We recently demonstrated the feasibility of combining enhanced tumor-to-tissue contrast and PET imaging for immunoscintigraphic tumor localization in pancreas and colon carcinoma bearing nude mice. Contrast enhancement was obtained with a multistep targeting technique that consists of the sequential administration of an antitumor/antihapten bispecific antibody (BS-MAb), a blocker to saturate the antihapten binding sites of the BS-MAb that remains in circulation, and a low molecular weight Ga chelate, labeled with the positron emitter 68 Ga, which serves as the hapten. To evaluate the efficacy of this pretargeting technique for breast cancer localization, we synthesized a BS-MAb from the F(ab') 2 fragments of the anti-MUC1 MAb 12H12 which reacts with the vast majority of human breast carcinomas, and the F(ab') fragment of an anti-Ga chelate MAb using a bifunctional chemical linker. The BS-MAb was tested for its affinity and its biokinetics in nude mice bearing a human mammary carcinoma. Equilibrium binding of the BS-MAb for mammary carcinoma cells was low (1.2 x 10 7 M -1 ) while the binding capacity of cells was high (8.4 x 10 6 BS-MAbs per cell). Tumor uptake of the 67 Ga labeled chelate in pretargeted animals was to 5.8 ± 0.8% iD/g resulting in a tumor-to-blood ratio of 2.6 at 1h postinjection. This compares with a ratio of 0.65 and 0.85 obtained with 125 I-labeled native 12H12 at 24h and 48h postinjection. No difference in the tumor uptake of both the 68 Ga and 67 Ga labeled chelate was observed. PET imaging of mice, started 1h postinjection of the 68 Ga chelate, clearly visualized all tumors

Pretargeting of human mammary carcinoma xenografts with bispecific anti-MUC1/anti-Ga chelate antibodies and immunoscintigraphy with PET

Energy Technology Data Exchange (ETDEWEB)

Schuhmacher, Jochen; Klivenyi, Gabor; Kaul, Sepp; Henze, Marcus; Matys, Ronald; Hauser, Harald; Clorius, John

2001-10-01

We recently demonstrated the feasibility of combining enhanced tumor-to-tissue contrast and PET imaging for immunoscintigraphic tumor localization in pancreas and colon carcinoma bearing nude mice. Contrast enhancement was obtained with a multistep targeting technique that consists of the sequential administration of an antitumor/antihapten bispecific antibody (BS-MAb), a blocker to saturate the antihapten binding sites of the BS-MAb that remains in circulation, and a low molecular weight Ga chelate, labeled with the positron emitter {sup 68}Ga, which serves as the hapten. To evaluate the efficacy of this pretargeting technique for breast cancer localization, we synthesized a BS-MAb from the F(ab'){sub 2} fragments of the anti-MUC1 MAb 12H12 which reacts with the vast majority of human breast carcinomas, and the F(ab') fragment of an anti-Ga chelate MAb using a bifunctional chemical linker. The BS-MAb was tested for its affinity and its biokinetics in nude mice bearing a human mammary carcinoma. Equilibrium binding of the BS-MAb for mammary carcinoma cells was low (1.2 x 10{sup 7} M{sup -1}) while the binding capacity of cells was high (8.4 x 10{sup 6} BS-MAbs per cell). Tumor uptake of the {sup 67}Ga labeled chelate in pretargeted animals was to 5.8 {+-} 0.8% iD/g resulting in a tumor-to-blood ratio of 2.6 at 1h postinjection. This compares with a ratio of 0.65 and 0.85 obtained with {sup 125}I-labeled native 12H12 at 24h and 48h postinjection. No difference in the tumor uptake of both the {sup 68}Ga and {sup 67}Ga labeled chelate was observed. PET imaging of mice, started 1h postinjection of the {sup 68}Ga chelate, clearly visualized all tumors.

Antiviral Activity of HIV gp120 Targeting Bispecific T Cell Engager (BiTE®) Antibody Constructs.

Science.gov (United States)

Brozy, Johannes; Schlaepfer, Erika; Mueller, Christina K S; Rochat, Mary-Aude; Rampini, Silvana K; Myburgh, Renier; Raum, Tobias; Kufer, Peter; Baeuerle, Patrick A; Muenz, Markus; Speck, Roberto F

2018-05-02

Today's gold standard in HIV therapy is the combined antiretroviral therapy (cART). It requires strict adherence by patients and life-long medication, which can lower the viral load below detection limits and prevent HIV-associated immunodeficiency, but cannot cure patients. The bispecific T cell engaging (BiTE®) antibody technology has demonstrated long-term relapse-free outcomes in patients with relapsed and refractory acute lymphocytic leukemia. We here generated BiTE® antibody constructs that target the HIV-1 envelope protein gp120 (HIV gp120) using either the scFv B12 or VRC01, the first two extracellular domains (1+2) of human CD4 alone or joined to the single chain variable fragment (scFv) of the antibody 17b fused to an anti-human CD3ϵ scFv. These engineered human BiTE® antibody constructs showed engagement of T cells for redirected lysis of HIV gp120-transfected CHO cells. Furthermore, they substantially inhibited HIV-1 replication in PBMCs as well as in macrophages co-cultured with autologous CD8+ T-cells, the most potent being the human CD4(1+2) BiTE® antibody construct and the CD4(1+2)L17b BiTE® antibody construct. The CD4(1+2) h BiTE® antibody construct promoted HIV infection of human CD4-/CD8+ T cells. In contrast, the neutralizing B12 and the VRC01 BiTE® antibody constructs as well as the CD4(1+2)L17b BiTE® antibody construct did not. Thus, BiTE® antibody constructs targeting HIV gp120 are very promising for constraining HIV and warrant further development as novel antiviral therapy with curative potential. Importance HIV is a chronic infection well controlled with the current cART. However, we lack cure of HIV, and the HIV pandemic goes on. Here we showed in vitro and ex vivo t hat a bispecific T-cell engaging (BiTE®) antibody construct targeting HIV gp120 resulted in substantially reduced HIV replication. In addition, these BiTE® antibody constructs display efficient killing of gp120 expressing cells and inhibited replication in ex vivo

CD3 directed bispecific antibodies induce increased lymphocyte-endothelial cell interactions in vitro

NARCIS (Netherlands)

Molema, G; Tervaert, JWC; Kroesen, BJ; Helfrich, W; Meijer, DKF; de Leij, LFMH

Bispecific antibody (BsMAb) BIS-1 has been developed to redirect the cytolytic activity of cytotoxic T lymphocytes (CTL) to epithelial glycoprotein-2 (EGP-2) expressing tumour cells; intravenous administration of BIS-1 F(ab')(2) to carcinoma patients in a phase I/II clinical trial, caused

A fundamental study of immunoscintigraphy with sup 131 I-labeled anti-CA 19-9 and anti-CEA monoclonal antibodies; Imaging of tumor-bearing mice by IMACIS-1 and cell ELISA with human tumor cells

Energy Technology Data Exchange (ETDEWEB)

Nogami, Toshihiko; Miura, Hiroshi; Ohmi, Shoichi; Kazahaya, Yasuhiro [CIS DIAGNOSTIC K.K., Chiba (Japan)

1990-05-01

A study was made on 2 types of {sup 131}I-labeled anti-CA 19-9 and anti-CEA mouse monoclonal antibodies (IMACIS-1) against human cancer related antigen as to their usefulness in radioimmunoimaging. Tumor-bearing nude mice were used for comparison. The transplanted tumors (SW948, COLO 201) were clearly visualized 48-72 hours after administration of IMACIS-1. Tumor/blood ratio 72 hours after administration: 8.69 in COLO 201 and 5.70 in SW948, showing ca. 10-15 times as high as those in PC-3 and HEp-2. IMACIS-1 therefore is considered useful in radioimmunoimaging of cancer. Analysis was made by in vitro cell ELISA. As a result, both of the cells specifically reacted with anti-CA 19-9 but not anti-CEA. (author).

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

Large-Scale Purification of r28M: A Bispecific scFv Antibody Targeting Human Melanoma Produced in Transgenic Cattle.

Directory of Open Access Journals (Sweden)

Katrin Spiesberger

Full Text Available 30 years ago, the potential of bispecific antibodies to engage cytotoxic T cells for the lysis of cancer cells was discovered. Today a variety of bispecific antibodies against diverse cell surface structures have been developed, the majority of them produced in mammalian cell culture systems. Beside the r28M, described here, no such bispecific antibody is known to be expressed by transgenic livestock, although various biologicals for medical needs are already harvested-mostly from the milk-of these transgenics. In this study we investigated the large-scale purification and biological activity of the bispecific antibody r28M, expressed in the blood of transgenic cattle. This tandem single-chain variable fragment antibody is designed to target human CD28 and the melanoma/glioblastoma-associated cell surface chondroitin sulfate proteoglycan 4 (CSPG4.With the described optimized purification protocol an average yield of 30 mg enriched r28M fraction out of 2 liters bovine plasma could be obtained. Separation of this enriched fraction by size exclusion chromatography into monomers, dimers and aggregates and further testing regarding the biological activity revealed the monomer fraction as being the most appropriate one to continue working with. The detailed characterization of the antibody's activity confirmed its high specificity to induce the killing of CSPG4 positive cells. In addition, first insights into tumor cell death pathways mediated by r28M-activated peripheral blood mononuclear cells were gained. In consideration of possible applications in vivo we also tested the effect of the addition of different excipients to r28M.Summing up, we managed to purify monomeric r28M from bovine plasma in a large-scale preparation and could prove that its biological activity is unaffected and still highly specific and thus, might be applicable for the treatment of melanoma.

Fab-dsFv: A bispecific antibody format with extended serum half-life through albumin binding.

Science.gov (United States)

Davé, Emma; Adams, Ralph; Zaccheo, Oliver; Carrington, Bruce; Compson, Joanne E; Dugdale, Sarah; Airey, Michael; Malcolm, Sarah; Hailu, Hanna; Wild, Gavin; Turner, Alison; Heads, James; Sarkar, Kaushik; Ventom, Andrew; Marshall, Diane; Jairaj, Mark; Kopotsha, Tim; Christodoulou, Louis; Zamacona, Miren; Lawson, Alastair D; Heywood, Sam; Humphreys, David P

2016-10-01

An antibody format, termed Fab-dsFv, has been designed for clinical indications that require monovalent target binding in the absence of direct Fc receptor (FcR) binding while retaining substantial serum presence. The variable fragment (Fv) domain of a humanized albumin-binding antibody was fused to the C-termini of Fab constant domains, such that the VL and VH domains were individually connected to the Cκ and CH1 domains by peptide linkers, respectively. The anti-albumin Fv was selected for properties thought to be desirable to ensure a durable serum half-life mediated via FcRn. The Fv domain was further stabilized by an inter-domain disulfide bond. The bispecific format was shown to be thermodynamically and biophysically stable, and retained good affinity and efficacy to both antigens simultaneously. In in vivo studies, the serum half-life of Fab-dsFv, 2.6 d in mice and 7.9 d in cynomolgus monkeys, was equivalent to Fab'-PEG.

Pharmacokinetics and Dosimetry Studies for Optimization of Pretargeted Radioimmunotherapy in CEA-Expressing Advanced Lung Cancer Patients

Directory of Open Access Journals (Sweden)

Caroline eBodet-Milin

2015-11-01

Full Text Available Objectives. A phase I pretargeted radioimmunotherapy trial (EudractCT 200800603096 was designed in patients with metastatic lung cancer expressing carcinoembryonic antigen (CEA to optimize bispecific antibody and labelled peptide doses, as well as the delay between their injections.Methods. Three cohorts of 3 patients received the anti-CEA x anti-histamine-succinyl-glycine (HSG humanized trivalent bispecific antibody (TF2 and the IMP288 bivalent HSG-peptide. Patients underwent a pre-therapeutic imaging session S1 (44 or 88 nmol/m2 of TF2 followed by 4.4 nmol/m2, 185 MBq, of 111In-labelled IMP288, and, 1-2 weeks later, a therapy session S2 (240 or 480 nmol/m2 of TF2 followed by 24 nmol/m2, 1.1 GBq/m2, 177Lu-labeled IMP288. The pretargeting delay was 24 or 48 hours. The dose schedule was defined based on pre-clinical TF2 pharmacokinetic studies, on our previous clinical data using the previous anti-CEA pretargeting system and on clinical results observed in the first patients injected using the same system in the Netherlands.Results. TF2 pharmacokinetics (PK was represented by a two-compartment model in which the central compartment volume was linearly dependent on the patient's surface area. PK were remarkably similar, with a clearance of 0.33 +/- 0.03 L/h per m2. 111In- and 177Lu-IMP288 PK were also well represented by a two-compartment model. IMP288 PK were faster (clearance 1.4 to 3.3 l/h. The central compartment volume was proportional to body surface area and IMP288clearance depended on the molar ratio of injected IMP288 to circulating TF2 at the time of IMP288 injection. Modelling of image quantification confirmed the dependence of IMP288 kinetics on circulating TF2, but tumour activity PK were variable. Organ absorbed doses were not significantly different in the 3 cohorts, but the tumour dose was significantly higher with the higher molar doses of TF2 (p < 0.002. S1 imaging predicted absorbed doses calculated in S2. Conclusion. The best

Fab-based bispecific antibody formats with robust biophysical properties and biological activity.

Science.gov (United States)

Wu, Xiufeng; Sereno, Arlene J; Huang, Flora; Lewis, Steven M; Lieu, Ricky L; Weldon, Caroline; Torres, Carina; Fine, Cody; Batt, Micheal A; Fitchett, Jonathan R; Glasebrook, Andrew L; Kuhlman, Brian; Demarest, Stephen J

2015-01-01

A myriad of innovative bispecific antibody (BsAb) platforms have been reported. Most require significant protein engineering to be viable from a development and manufacturing perspective. Single-chain variable fragments (scFvs) and diabodies that consist only of antibody variable domains have been used as building blocks for making BsAbs for decades. The drawback with Fv-only moieties is that they lack the native-like interactions with CH1/CL domains that make antibody Fab regions stable and soluble. Here, we utilize a redesigned Fab interface to explore 2 novel Fab-based BsAbs platforms. The redesigned Fab interface designs limit heavy and light chain mixing when 2 Fabs are co-expressed simultaneously, thus allowing the use of 2 different Fabs within a BsAb construct without the requirement of one or more scFvs. We describe the stability and activity of a HER2×HER2 IgG-Fab BsAb, and compare its biophysical and activity properties with those of an IgG-scFv that utilizes the variable domains of the same parental antibodies. We also generated an EGFR × CD3 tandem Fab protein with a similar format to a tandem scFv (otherwise known as a bispecific T cell engager or BiTE). We show that the Fab-based BsAbs have superior biophysical properties compared to the scFv-based BsAbs. Additionally, the Fab-based BsAbs do not simply recapitulate the activity of their scFv counterparts, but are shown to possess unique biological activity.

Re-engineering therapeutic antibodies for Alzheimer's disease as blood-brain barrier penetrating bi-specific antibodies.

Science.gov (United States)

Pardridge, William M

2016-12-01

Therapeutic antibodies are large molecule drugs that do not cross the blood-brain barrier (BBB). Therefore, drug development of therapeutic antibodies for Alzheimer's disease (AD) requires that these molecules be re-engineered to enable BBB delivery. This is possible by joining the therapeutic antibody with a transporter antibody, resulting in the engineering of a BBB-penetrating bispecific antibody (BSA). Areas covered: The manuscript covers transporter antibodies that cross the BBB via receptor-mediated transport systems on the BBB, such as the insulin receptor or transferrin receptor. Furthermore, it highlights therapeutic antibodies for AD that target the Abeta amyloid peptide, beta secretase-1, or the metabotropic glutamate receptor-1. BSAs are comprised of both the transporter antibody and the therapeutic antibody, as well as IgG constant region, which can induce immune tolerance or trigger transport via Fc receptors. Expert opinion: Multiple types of BSA molecular designs have been used to engineer BBB-penetrating BSAs, which differ in valency and spatial orientation of the transporter and therapeutic domains of the BSA. The plasma pharmacokinetics and dosing regimens of BSAs differ from that of conventional therapeutic antibodies. BBB-penetrating BSAs may be engineered in the future as new treatments of AD, as well as other neural disorders.

Immunoscintigraphy of Colorectal and Other Gastrointestinal Cancers with Radioactive Monoclonal Antibodies to CEA and CA 19 - 9

International Nuclear Information System (INIS)

Jang, Dae Hwan; Choi, Duck Joo; Lee, Bum Woo; Park, Won; Han, Chang Soon; Kim, Hak San; Kim, Chong Soon

1988-01-01

The cocktails of two 131 I labeled Monoclonal antibody (MCAB) (Anti CA 19-9 F(ab') 2 +Anti CEA F(ab') 2 fragment), which react specially, with human gastrointestinal cancers, were administered to 10 patients with colorectal (7), stomach (2) and pancreas (l) cancer for scintigraphic detection. All patients were known or postoperatively recurrent cases, and serum tumor markers, CA 19-9 and CEA, were measured with immunoradiometric assay, just before immunoscintigraphy (ISG). The tumor marker's level in serum is not correlated with positive tumor uptake in ISG. The sensitivity and specificity of ISG in detection of 21 tumor sites, based on surgery, CT, ultrasonography and pathology, were 90.5% and 100%. One case of colon cancer showed gall bladder metastasis, which was neglected on CT study. Tumor/non tumor uptake ratio of radiolabelled antibody were progressively increased from day 3 to day 7 during study. We summarized as follows: 1) The use of cocktails of CEA and CA 19-9 MCAB F(ab') 2 increased sensitivity and specificity in ISG. 2) Delayed imaging (later than 5 days) increases sensitivity and specificity due to exclusion of nonspecific iodine accumulation in stomach and lung. 3) Second tracer technique is essential for anatomical landmark by use of a double isotope scan, but subtraction technique, a possible source of artifacts, is no longer necessary when delayed imaging is performed. 4) It may be possible to use two MCAB cocktails of CA 19-9 and CEA in Radioimmunodetection of stomach and pancreas cancer. In conclusion, ISG using MCAB cocktails, F(ab') 2 fragment of anti CA 19-9 and Anti CEA, provide additional opportunity for tumor localization and detection of colorectal and other G-I cancer, such as stomach and pancreas.

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

Reagents for radioimmunological determination of carcinoembryonic antigen (CEA)

International Nuclear Information System (INIS)

Albert, Z.; Balbierz, H.; Breberowicz, J.

1978-01-01

The work was undertaken to prepare the reagents for carcinoembryonic antigen (CEA) radioimmunoassay with double antibody method. The CEA standard of high immunoreactivity was prepared and purified. The purified CEA was used for immunozation of goats. The goat anti - CEA sera were received. IgG fraction from normal goat serum was purified and used for the production of horse anti-goat IgG serum which was then used in the radioimmunoassay of CEA. The labelling of CEA with iodine-125 has been carried out be means of the enzymatic method.(Z.R.)

Approaches to lung cancer treatment using the CD3E x GP-2-directed bispecific monoclonal antibody BIS-1

NARCIS (Netherlands)

Kroesen, BJ; Nieken, J; Sleijfer, DT; Molema, G; deVries, EGE; Groen, HJM; Helfrich, W; The, TH; Mulder, NH; deLeij, L

1997-01-01

The bispecific monoclonal antibody (bsAb) BIS-1 combines a monoclonal-antibody(mAb)-defined specificity for the CD3 complex, as present on all T lymphocytes, with a mAb-defined specificity for the pancarcinoma/epithelium associated glycoprotein EGP-2. In vitro studies indicate that BIS-1 can direct

Targeting and killing of glioblastoma with activated T cells armed with bispecific antibodies

International Nuclear Information System (INIS)

Zitron, Ian M; Thakur, Archana; Norkina, Oxana; Barger, Geoffrey R; Lum, Lawrence G; Mittal, Sandeep

2013-01-01

Since most glioblastomas express both wild-type EGFR and EGFRvIII as well as HER2/neu, they are excellent targets for activated T cells (ATC) armed with bispecific antibodies (BiAbs) that target EGFR and HER2. ATC were generated from PBMC activated for 14 days with anti-CD3 monoclonal antibody in the presence of interleukin-2 and armed with chemically heteroconjugated anti-CD3×anti-HER2/neu (HER2Bi) and/or anti-CD3×anti-EGFR (EGFRBi). HER2Bi- and/or EGFRBi-armed ATC were examined for in vitro cytotoxicity using MTT and 51 Cr-release assays against malignant glioma lines (U87MG, U118MG, and U251MG) and primary glioblastoma lines. EGFRBi-armed ATC killed up to 85% of U87, U118, and U251 targets at effector:target ratios (E:T) ranging from 1:1 to 25:1. Engagement of tumor by EGFRBi-armed ATC induced Th1 and Th2 cytokine secretion by armed ATC. HER2Bi-armed ATC exhibited comparable cytotoxicity against U118 and U251, but did not kill HER2-negative U87 cells. HER2Bi- or EGFRBi-armed ATC exhibited 50—80% cytotoxicity against four primary glioblastoma lines as well as a temozolomide (TMZ)-resistant variant of U251. Both CD133– and CD133+ subpopulations were killed by armed ATC. Targeting both HER2Bi and EGFRBi simultaneously showed enhanced efficacy than arming with a single BiAb. Armed ATC maintained effectiveness after irradiation and in the presence of TMZ at a therapeutic concentration and were capable of killing multiple targets. High-grade gliomas are suitable for specific targeting by armed ATC. These data, together with additional animal studies, may provide the preclinical support for the use of armed ATC as a valuable addition to current treatment regimens

Development of an affinity-matured humanized anti-epidermal growth factor receptor antibody for cancer immunotherapy.

Science.gov (United States)

Nakanishi, Takeshi; Maru, Takamitsu; Tahara, Kazuhiro; Sanada, Hideaki; Umetsu, Mitsuo; Asano, Ryutaro; Kumagai, Izumi

2013-02-01

We showed previously that humanization of 528, a murine anti-epidermal growth factor receptor (EGFR) antibody, causes reduced affinity for its target. Here, to improve the affinity of the humanized antibody for use in cancer immunotherapy, we constructed phage display libraries focused on the complementarity-determining regions (CDRs) of the antibody and carried out affinity selection. Two-step selections using libraries constructed in a stepwise manner enabled a 32-fold affinity enhancement of humanized 528 (h528). Thermodynamic analysis of the interactions between the variable domain fragment of h528 (h528Fv) mutants and the soluble extracellular domain of EGFR indicated that the h528Fv mutants obtained from the first selection showed a large increase in negative enthalpy change due to binding, resulting in affinity enhancement. Furthermore, mutants from the second selection showed a decrease in entropy loss, which led to further affinity maturation. These results suggest that a single mutation in the heavy chain variable domain (i.e. Tyr(52) to Trp) enthalpically contributed for overcoming the energetic barrier to the antigen-antibody interaction, which was a major hurdle for the in vitro affinity maturation of h528. We reported previously that the humanized bispecific diabody hEx3 Db, which targets EGFR and CD3, shows strong anti-tumor activity. hEx3 Db mutants, in which the variable domains of h528 were replaced with those of the affinity-enhanced mutants, were prepared and characterized. In a growth inhibition assay of tumor cells, the hEx3 Db mutants showed stronger anti-tumor activity than that of hEx3 Db, suggesting that affinity enhancement of h528Fv enhances the anti-tumor activity of the bispecific diabody.

A new approach for generating bispecific antibodies based on a common light chain format and the stable architecture of human immunoglobulin G1.

Science.gov (United States)

De Nardis, Camilla; Hendriks, Linda J A; Poirier, Emilie; Arvinte, Tudor; Gros, Piet; Bakker, Alexander B H; de Kruif, John

2017-09-01

Bispecific antibodies combine two different antigen-binding sites in a single molecule, enabling more specific targeting, novel mechanisms of action, and higher clinical efficacies. Although they have the potential to outperform conventional monoclonal antibodies, many bispecific antibodies have issues regarding production, stability, and pharmacokinetic properties. Here, we describe a new approach for generating bispecific antibodies using a common light chain format and exploiting the stable architecture of human immunoglobulin G 1 We used iterative experimental validation and computational modeling to identify multiple Fc variant pairs that drive efficient heterodimerization of the antibody heavy chains. Accelerated stability studies enabled selection of one Fc variant pair dubbed "DEKK" consisting of substitutions L351D and L368E in one heavy chain combined with L351K and T366K in the other. Solving the crystal structure of the DEKK Fc region at a resolution of 2.3 Å enabled detailed analysis of the interactions inducing CH3 interface heterodimerization. Local shifts in the IgG backbone accommodate the introduction of lysine side chains that form stabilizing salt-bridge interactions with substituted and native residues in the opposite chain. Overall, the CH3 domain adapted to these shifts at the interface, yielding a stable Fc conformation very similar to that in wild-type IgG. Using the DEKK format, we generated the bispecific antibody MCLA-128, targeting human EGF receptors 2 and 3. MCLA-128 could be readily produced and purified at industrial scale with a standard mammalian cell culture platform and a routine purification protocol. Long-term accelerated stability assays confirmed that MCLA-128 is highly stable and has excellent biophysical characteristics. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

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.)

Comparative imaging and biodistribution studies with an anti-CEA monoclonal antibody and its F(ab)2 and Fab fragments in mice with colon carcinoma xenografts

International Nuclear Information System (INIS)

Andrew, S.M.; Pimm, M.V.; Baldwin, R.W.; Perkins, A.C.

1986-01-01

An IgG1 mouse monoclonal antibody directed against CEA has been digested with papain to yield F(ab) 2 and Fab fragments. Following radioiodination, intact antibody and fragments showed specific binding to cells of a CEA-producing tumour, although the immune reactivities of the fragments were lower than that of intact antibody. Gamma scintigraphy of nude mice bearing CEA producing human tumour xenografts and injected with 131 I-labelled fragments showed earlier and superior imaging of tumours than did 131 I-intact antibody, and this was most marked with the Fab fragment. Sequential dissection analyses showed that this was due to earlier and higher tumour-to-blood ratios with fragments than with intact antibody, but in absolute terms the degree of localization of both fragment types was significantly lower than that of intact antibody. (orig.)

Radioimmunoscintigraphy with 99mTc-labelled anti-CEA monoclonal antibodies in colorectal carcinoma patients

International Nuclear Information System (INIS)

Sergieva, S.; Baychev, G.; Tzingilev, D.; Delijski, T.; Kirova, G.; Kirilova, B.; Nenovska, M.

1998-01-01

Sixteen patients (2 female and 14 male, aged 42-75) were given intravenous injections with 99m Tc (555-740 MBq)-labelled anti-CEA MAb (CEA-Scan, Mallinckrodt Medical and M-CEATEC, Sorin Biomedica). Five of them were with duly established or established or suspected primary colorectal carcinoma, and eleven were studied postoperatively after recording an increase CEA levels in serum. The patients were scanned within 4-24 h of infusion using planar and tomographic imaging in rotation gamma-camera DIACAM (Siemens). At all 16 patients 27 true positive results were obtained: in 7 primary colorectal carcinomas, 5 locally recurrent tumors, 7 liver metastases, 6 lymphogeneous lesions and two - in the ureteral region. True negative results were established at three patients, false positive - in one patient with chronic inflammation, and false negative results - in 3 cases with liver metastases foci < 8 mm. Having 90 % sensitivity, 75 % specificity and 82.3 % accuracy, radioimmunoscintigraphy is a highly informative and sensitive imaging method for diagnosing and following up of primary, recurrent and metastatic foci in colorectal carcinoma patients. (author)

Cell Penetrating Bispecific Antibodies for Targeting Oncogenic Transcription Factors in Advanced Prostate Cancer

Science.gov (United States)

2016-12-01

The pCMhAR plasmid was mutagenized to produce a Q680X variant, with a premature stop codon. We decided not to study the E231G mutation since current...compared two methods of producing 3E10-AR441 as a secreted protein in Pichia pastoris : a. the standard method of growing yeast in glycerol and then...3E10-AR441 bispecific antibody. L. Demonstration that scFv AR441 sequences prevent secretion of fusion proteins in yeast . We have used a yeast

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

Structural considerations for functional anti-EGFR × anti-CD3 bispecific diabodies in light of domain order and binding affinity.

Science.gov (United States)

Asano, Ryutaro; Nagai, Keisuke; Makabe, Koki; Takahashi, Kento; Kumagai, Takashi; Kawaguchi, Hiroko; Ogata, Hiromi; Arai, Kyoko; Umetsu, Mitsuo; Kumagai, Izumi

2018-03-02

We previously reported a functional humanized bispecific diabody (bsDb) that targeted EGFR and CD3 (hEx3-Db) and enhancement of its cytotoxicity by rearranging the domain order in the V domain. Here, we further dissected the effect of domain order in bsDbs on their cross-linking ability and binding kinetics to elucidate general rules regarding the design of functional bsDbs. Using Ex3-Db as a model system, we first classified the four possible domain orders as anti-parallel (where both chimeric single-chain components are variable heavy domain (VH)-variable light domain (VL) or VL-VH order) and parallel types (both chimeric single-chain components are mixed with VH-VL and VL-VH order). Although anti-parallel Ex3-Dbs could cross-link the soluble target antigens, their cross-linking ability between soluble targets had no correlation with their growth inhibitory effects. In contrast, the binding affinity of one of the two constructs with a parallel-arrangement V domain was particularly low, and structural modeling supported this phenomenon. Similar results were observed with E2x3-Dbs, in which the V region of the anti-EGFR antibody clone in hEx3 was replaced with that of another anti-EGFR clone. Only anti-parallel types showed affinity-dependent cancer inhibitory effects in each molecule, and E2x3-LH (both components in VL-VH order) showed the most intense anti-tumor activity in vitro and in vivo . Our results showed that, in addition to rearranging the domain order of bsDbs, increasing their binding affinity may be an ideal strategy for enhancing the cytotoxicity of anti-parallel constructs and that E2x3-LH is particularly attractive as a candidate next-generation anti-cancer drug.

PSMA-targeted bispecific Fab conjugates that engage T cells.

Science.gov (United States)

Patterson, James T; Isaacson, Jason; Kerwin, Lisa; Atassi, Ghazi; Duggal, Rohit; Bresson, Damien; Zhu, Tong; Zhou, Heyue; Fu, Yanwen; Kaufmann, Gunnar F

2017-12-15

Bioconjugate formats provide alternative strategies for antigen targeting with bispecific antibodies. Here, PSMA-targeted Fab conjugates were generated using different bispecific formats. Interchain disulfide bridging of an αCD3 Fab enabled installation of either the PSMA-targeting small molecule DUPA (SynFab) or the attachment of an αPSMA Fab (BisFab) by covalent linkage. Optimization of the reducing conditions was critical for selective interchain disulfide reduction and good bioconjugate yield. Activity of αPSMA/CD3 Fab conjugates was tested by in vitro cytotoxicity assays using prostate cancer cell lines. Both bispecific formats demonstrated excellent potency and antigen selectivity. Copyright © 2017. Published by Elsevier Ltd.

Preparation of one-vial reduced anti-CEA kit

International Nuclear Information System (INIS)

Hamada, Elena Setuko; Muramoto, Emiko; Shiraishi, Emilia Mayumi; Silva, Licia Maria Britto da; Martins, Heidi Pinto; Silva, Constanca Pagano Goncalves da

1996-01-01

A rapid and reliable instant reduced anti-CEA lyophilized kit for labelling with 99m Tc was developed. Each vial contains 0.5 mg of reduced anti-CEA, 40 μg of mendronate (MDP), 2.75 μg stannous fluoride (Sn F 2 ) and 15 μ g p-aminobenzoic acid (PABA). Labeling efficiency and stability were higher than 95% and were determined by instant paper chromatography. Biodistribution studies were performed in normal isogenic BALB/c mice at 4,6 and 24 hours after intravenous administration of the radiolabelled product. The maximum amount of activity was accumulated in the liver followed by intestines and kidneys. (author)

Exploiting light chains for the scalable generation and platform purification of native human bispecific IgG

Science.gov (United States)

Fischer, Nicolas; Elson, Greg; Magistrelli, Giovanni; Dheilly, Elie; Fouque, Nicolas; Laurendon, Amélie; Gueneau, Franck; Ravn, Ulla; Depoisier, Jean-François; Moine, Valery; Raimondi, Sylvain; Malinge, Pauline; Di Grazia, Laura; Rousseau, François; Poitevin, Yves; Calloud, Sébastien; Cayatte, Pierre-Alexis; Alcoz, Mathias; Pontini, Guillemette; Fagète, Séverine; Broyer, Lucile; Corbier, Marie; Schrag, Delphine; Didelot, Gérard; Bosson, Nicolas; Costes, Nessie; Cons, Laura; Buatois, Vanessa; Johnson, Zoe; Ferlin, Walter; Masternak, Krzysztof; Kosco-Vilbois, Marie

2015-01-01

Bispecific antibodies enable unique therapeutic approaches but it remains a challenge to produce them at the industrial scale, and the modifications introduced to achieve bispecificity often have an impact on stability and risk of immunogenicity. Here we describe a fully human bispecific IgG devoid of any modification, which can be produced at the industrial scale, using a platform process. This format, referred to as a κλ-body, is assembled by co-expressing one heavy chain and two different light chains, one κ and one λ. Using ten different targets, we demonstrate that light chains can play a dominant role in mediating specificity and high affinity. The κλ-bodies support multiple modes of action, and their stability and pharmacokinetic properties are indistinguishable from therapeutic antibodies. Thus, the κλ-body represents a unique, fully human format that exploits light-chain variable domains for antigen binding and light-chain constant domains for robust downstream processing, to realize the potential of bispecific antibodies. PMID:25672245

Antibody dependent cellular phagocytosis (ADCP) and antibody dependent cellular cytotoxicity (ADCC) of breast cancer cells mediated by bispecific antibody, MDX-210.

Science.gov (United States)

Watanabe, M; Wallace, P K; Keler, T; Deo, Y M; Akewanlop, C; Hayes, D F

1999-02-01

MDX-210 is a bispecific antibody (BsAb) with specificity for both the proto-oncogene product of HER-2/neu (c-erbB-2) and FcgammaRI (CD64). HER-2/neu is overexpressed in malignant tissue of approximately 30% of patients with breast cancer, and FcgammaRI is expressed on human monocytes, macrophages, and IFN-gamma activated granulocytes. We investigated phagocytosis and cytolysis of cultured human breast cancer cells by human monocyte-derived macrophages (MDM) mediated by BsAb MDX-210, its partially humanized derivative (MDX-H210), and its parent MoAb 520C9 (anti-HER-2/neu) under various conditions. Purified monocytes were cultured with GM-CSF, M-CSF, or no cytokine for five or six days. Antibody dependent cellular phagocytosis (ADCP) and cytolysis (ADCC) assays were performed with the MDM and HER-2/neu positive target cells (SK-BR-3). ADCP was measured by two-color fluorescence flow cytometry using PKH2 (green fluorescent dye) and phycoerythrin-conjugated (red) monoclonal antibodies (MoAb) against human CD14 and CD11b. ADCC was measured with a non-radioactive LDH detection kit. Both BsAb MDX-210 (via FcgammaRI) and MoAb 520C9 (mouse IgG1, via FcgammaRII) mediated similar levels of ADCP and ADCC. ADCP mediated by BsAb MDX-H210 was identical to that mediated by BsAb MDX-210. Confocal microscopy demonstrated that dual-labeled cells represented true phagocytosis. Both ADCP and ADCC were higher when MDM were pre-incubated with GM-CSF than when incubated with M-CSF. BsAb MDX-210 is as active in vitro as the parent MoAb 520C9 in inducing both phagocytosis and cytolysis of MDM. MDX-210 and its partially humanized derivative, MDX-H210, mediated similar levels of ADCP. GM-CSF appears to superior to M-CSF in inducing MDM-mediated ADCC and ADCP. These studies support the ongoing clinical investigations of BsAb MDX-210 and its partially humanized derivative.

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

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)

Chimeric bispecific OC/TR monoclonal antibody mediates lysis of tumor cells expressing the folate-binding protein (MOv18) and displays decreased immunogenicity in patients

NARCIS (Netherlands)

Luiten, R. M.; Warnaar, S. O.; Sanborn, D.; Lamers, C. H.; Bolhuis, R. L.; Litvinov, S. V.; Zurawski, V. R.; Coney, L. R.

1997-01-01

The bispecific OC/TR monoclonal antibody (mAb) cross-links the CD3 molecule on T cells with the human folate-binding protein (FBP), which is highly expressed on nonmucinous ovarian carcinomas. Clinical trials of patients with ovarian carcinoma with the OC/TR mAb have shown some complete and partial

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

Tandem bispecific broadly neutralizing antibody - a novel approach to HIV-1 treatment.

Science.gov (United States)

Ferrari, Guido

2018-04-23

The last decade has led to a significant advance in our knowledge of HIV-1 latency and immunity. However, we are still not close to finding a cure for HIV-1. Although combination antiretroviral therapy (cART) has led to increased survival, almost close to that of the general population, it is still not curative. In the current issue of the JCI, Wu et al. studied the prophylactic and therapeutic potential of an engineered tandem bispecific broadly neutralizing antibody (bs-bnAb), BiIA-SG. This bnAb's breadth and potency were highly effective in protection and treatment settings, as measured by complete viremia control following direct infusion, as well as elimination of infected cells and delay in viral rebound when delivered with a recombinant vector. These observations underscore the need for the clinical development of BiIA-SG for the prevention of HIV-1.

Pharmacokinetics of the FO23C5 anti-CEA antibody fragment labelled with 99Tcm and 111In: a comparison in patients

International Nuclear Information System (INIS)

Hnatowich, D.J.; Mardirossian, G.; Rusckowski, M.; Roy, S.; Busche, H.; Griffin, T.W.; Brill, A.B.

1993-01-01

The FO23C5 anti-carcinoembryonic antigen (CEA) F(ab') 2 antibody was radiolabelled with sup(111)In via diethylenetriaminepentaacetic acid (DTPA) and directly with 99 Tc m by stannous ion and mercaptoethanol antibody reduction to compare the pharmacokinetics of these three agents. Four patients received 15 mCi 99 Tc m -Fab' 1 week before receiving 1 mCi 111 In-F(ab') 2 . Five additional patients received only the 99 Tc m -Fab'. The biodistribution of 99 Tc m was as expected for a labelled Fab' fragment: relative to 111 In, 99 Tc m cleared rapidly from circulation and into kidneys and urine. Liver levels of 111 In and 99 Tc m were surprisingly similar at 1 day although initial 111 In levels were lower and increased while 99 Tc m levels were higher and decreased. Spleen levels were also similar. In 4/9 patients receiving 99 Tc m , hepatobiliary clearance was observed at levels which could confuse interpretation whereas this mode of clearance was observed in only 1/4 patients receiving 111 In. Image quality was superior with 111 In versus 99 Tc m at 1 day postadministration as judged by counting rates and background activity whereas the opposite was true at 2-3 h postadministration. (author)

Expression of inhibitory receptors on intratumoral T cells modulates the activity of a T cell-bispecific antibody targeting folate receptor

OpenAIRE

Schreiner, Jens; Thommen, Daniela S.; Herzig, Petra; Bacac, Marina; Klein, Christian; Roller, Andreas; Belousov, Anton; Levitsky, Victor; Savic, Spasenija; Moersig, Wolfgang; Uhlenbrock, Franziska; Heinzelmann-Schwarz, Viola A.; Umana, Pablo; Pisa, Pavel; Lardinois, Didier

2015-01-01

T-cell bispecific antibodies (TCBs) are a novel therapeutic tool designed to selectively recruit T-cells to tumor cells and simultaneously activate them. However, it is currently unknown whether the dysfunctional state of T-cells, embedded into the tumor microenvironment, imprints on the therapeutic activity of TCBs. We performed a comprehensive analysis of activation and effector functions of tumor-infiltrating T-cells (TILs) in different tumor types, upon stimulation by a TCB targeting fola...

Time resolved native ion-mobility mass spectrometry to monitor dynamics of IgG4 Fab arm exchange and "bispecific" monoclonal antibody formation.

Science.gov (United States)

Debaene, François; Wagner-Rousset, Elsa; Colas, Olivier; Ayoub, Daniel; Corvaïa, Nathalie; Van Dorsselaer, Alain; Beck, Alain; Cianférani, Sarah

2013-10-15

Monoclonal antibodies (mAbs) and derivatives such as antibody-drug conjugates (ADC) and bispecific antibodies (bsAb), are the fastest growing class of human therapeutics. Most of the therapeutic antibodies currently on the market and in clinical trials are chimeric, humanized, and human immunoglobulin G1 (IgG1). An increasing number of IgG2s and IgG4s that have distinct structural and functional properties are also investigated to develop products that lack or have diminished antibody effector functions compared to IgG1. Importantly, wild type IgG4 has been shown to form half molecules (one heavy chain and one light chain) that lack interheavy chain disulfide bonds and form intrachain disulfide bonds. Moreover, IgG4 undergoes a process of Fab-arm exchange (FAE) in which the heavy chains of antibodies of different specificities can dissociate and recombine in bispecific antibodies both in vitro and in vivo. Here, native mass spectrometry (MS) and time-resolved traveling wave ion mobility MS (TWIM-MS) were used for the first time for online monitoring of FAE and bsAb formation using Hz6F4-2v3 and natalizumab, two humanized IgG4s which bind to human Junctional Adhesion Molecule-A (JAM-A) and alpha4 integrin, respectively. In addition, native MS analysis of bsAb/JAM-A immune complexes revealed that bsAb can bind up to two antigen molecules, confirming that the Hz6F4 family preferentially binds dimeric JAM-A. Our results illustrate how IM-MS can rapidly assess bsAb structural heterogeneity and be easily implemented into MS workflows for bsAb production follow up and bsAb/antigen complex characterization. Altogether, these results provide new MS-based methodologies for in-depth FAE and bsAb formation monitoring. Native MS and IM-MS will play an increasing role in next generation biopharmaceutical product characterization like bsAbs, antibody mixtures, and antibody-drug conjugates (ADC) as well as for biosimilar and biobetter antibodies.

Bispecific antibody complex pre-targeting and targeted delivery of polymer drug conjugates for imaging and therapy in dual human mammary cancer xenografts. Targeted polymer drug conjugates for cancer diagnosis and therapy

Energy Technology Data Exchange (ETDEWEB)

Khaw, Ban-An; Gada, Keyur S.; Patil, Vishwesh; Panwar, Rajiv; Mandapati, Savitri [Northeastern University, Department of Pharmaceutical Sciences, Bouve College of Health Sciences, School of Pharmacy, Boston, MA (United States); Hatefi, Arash [Rutgers University, Department of Pharmaceutics, New Brunswick, NJ (United States); Majewski, Stan [West Virginia University, Department of Radiology, Morgantown, WV (United States); Weisenberger, Andrew [Thomas Jefferson National Accelerator Facility, Jefferson Lab, Newport News, VA (United States)

2014-08-15

Doxorubicin, a frontline chemotherapeutic agent, limited by its cardiotoxicity and other tissue toxicities, was conjugated to N-terminal DTPA-modified polyglutamic acid (D-Dox-PGA) to produce polymer pro-drug conjugates. D-Dox-PGA or Tc-99 m labeled DTPA-succinyl-polylysine polymers (DSPL) were targeted to HER2-positive human mammary carcinoma (BT-474) in a double xenografted SCID mouse model also hosting HER2-negative human mammary carcinoma (BT-20). After pretargeting with bispecific anti-HER2-affibody-anti-DTPA-Fab complexes (BAAC), anti-DTPA-Fab or only phosphate buffered saline, D-Dox-PGA or Tc-99 m DSPL were administered. Positive therapeutic control mice were injected with Dox alone at maximum tolerated dose (MTD). Only BT-474 lesions were visualized by gamma imaging with Tc-99 m-DSPL; BT-20 lesions were not. Therapeutic efficacy was equivalent in mice pretargeted with BAAC/targeted with D-Dox-PGA to mice treated only with doxorubicin. There was no total body weight (TBW) loss at three times the doxorubicin equivalent MTD with D-Dox-PGA, whereas mice treated with doxorubicin lost 10 % of TBW at 2 weeks and 16 % after the second MTD injection leading to death of all mice. Our cancer imaging and pretargeted therapeutic approaches are highly target specific, delivering very high specific activity reagents that may result in the development of a novel theranostic application. HER/2 neu specific affibody-anti-DTPA-Fab bispecific antibody pretargeting of HER2 positive human mammary xenografts enabled exquisite targeting of polymers loaded with radioisotopes for molecular imaging and doxorubicin for effective therapy without the associating non-tumor normal tissue toxicities. (orig.)

Targeting Human C-Type Lectin-Like Molecule-1 (CLL1) with a Bispecific Antibody for Acute Myeloid Leukemia Immunotherapy**

OpenAIRE

Lu, Hua; Zhou, Quan; Deshmukh, Vishal; Phull, Hardeep; Ma, Jennifer; Tardif, Virginie; Naik, Rahul R.; Bouvard, Claire; Zhang, Yong; Choi, Seihyun; Lawson, Brian R.; Zhu, Shoutian; Kim, Chan Hyuk; Schultz, Peter G.

2014-01-01

Acute myeloid leukemia (AML), the most common acute adult leukemia and the second most common pediatric leukemia, still has a poor prognosis. Human C-type lectin-like molecule-1 (CLL1) is a recently identified myeloid lineage restricted cell surface marker, which is overexpressed in over 90% of AML patient myeloid blasts and in leukemic stem cells. Here, we describe the synthesis of a novel bispecific antibody, αCLL1-αCD3, using the genetically encoded unnatural amino acid, p-acetylphenylalan...

Highly efficient elimination of colorectal tumor-initiating cells by an EpCAM/CD3-bispecific antibody engaging human T cells.

Directory of Open Access Journals (Sweden)

Ines Herrmann

2010-10-01

Full Text Available With their resistance to genotoxic and anti-proliferative drugs and potential to grow tumors and metastases from very few cells, cancer stem or tumor-initiating cells (TICs are a severe limitation for the treatment of cancer by conventional therapies. Here, we explored whether human T cells that are redirected via an EpCAM/CD3-bispecific antibody called MT110 can lyse colorectal TICs and prevent tumor growth from TICs. MT110 recognizes EpCAM, a cell adhesion molecule expressed on TICs from diverse human carcinoma, which was recently shown to promote tumor growth through engagement of elements of the wnt pathway. MT110 was highly potent in mediating complete redirected lysis of KRAS-, PI3 kinase- and BRAF-mutated colorectal TICs, as demonstrated in a soft agar assay. In immunodeficient mice, MT110 prevented growth of tumors from a 5,000-fold excess of a minimally tumorigenic TIC dose. T cells engaged by MT110 may provide a potent therapeutic means to eradicate TICs and bulk tumor cells derived thereof.

Specificity of anti-phospholipid antibodies in infectious mononucleosis: a role for anti-cofactor protein antibodies

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Sorice, M; Pittoni, V; Griggi, T; Losardo, A; Leri, O; Magno, M S; Misasi, R; Valesini, G

2000-01-01

The antigen specificity of anti-phospholipid antibodies in infectious mononucleosis (IM) was studied using ELISA for the detection of anti-β2-glycoprotein I (β2-GPI), anti-annexin V, anti-protein S and anti-prothrombin antibodies and TLC immunostaining for the detection of anti-phospholipid antibodies. This technique enabled us to look at antibodies reacting to ‘pure’ phospholipid antigens in the absence of protein contamination. Sera from 46 patients with IM, 18 with systemic lupus erythematosus (SLE), 21 with primary anti-phospholipid antibody syndrome (PAPS), 50 with Helicobacter pylori infection and 30 healthy blood donors were tested. This study highlights anti-phospholipid antibodies in patients with IM as specific ‘pure’ anti-cardiolipin antibodies, while in PAPS and SLE patients anti-phosphatidylserine and anti-phosphatidylethanolamine antibodies were also found. This investigation also shows that the anti-cardiolipin antibodies found in IM can be present with anti-cofactor protein antibodies. The higher prevalence of anti-cofactor antibodies found in IM sera than in Helicobacter pylori sera may be due to the immunostimulatory effect and/or the polyclonal activation often observed in course of Epstein–Barr virus infection. However, anti-β2-GPI and, to a lesser extent, anti-prothrombin antibodies occur with a significantly lower prevalence in IM than in PAPS patients. This finding suggests that these antibodies should be regarded as the expression of the broad autoimmune syndrome involving the phospholipid-binding plasma proteins. PMID:10792380

Use and limitations of radiolabelled anti-CEA antibodies and their fragments for photoscanning detection of human colorectal carcinomas

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Mach, J P; Forni, M; Ritschard, J; Buchegger, F; Carrel, S; Widgren, S; Donath, A; Alberto, P [Lausanne Univ. (Switzerland)

1980-08-01

Fifty-three patients with histologically proven carcinoma were injected with highly purified (/sup 131/I)-labelled goat antibodies or fragments of antibodies against carcinoembryonic antigen (CEA). Each patient was tested by external photoscanning 4, 24, 36, 48h after injection. In 22 patients (16 of 38 injected with intact antibodies, 5 of 13 with F(ab')/sub 2/ fragments and 1 of 2 with Fab' fragments), an increased concentration of /sup 131/I radioactivity corresponding to the previously known tumor location was detected by photoscanning 36-48 h after injection. Blood pool and secreted radioactivity was determined in all patients by injecting 15 min after scanning, (sup(99m)Tc)-labeled normal serum albumin and free sup(99m)TcO/sub 4//sup -/. The computerized subtraction of sup(99m)Tc from /sup 131/I radioactivity enhanced the definition of tumor localization in the 22 positive patients. However, in spite of the computerized subtraction, interpretation of the scans remained doubtful for 12 patients and was entirely negative for 19 additional patients.

Impact of Diverse Immune Evasion Mechanisms of Cancer Cells on T Cells Engaged by EpCAM/CD3-Bispecific Antibody Construct AMG 110.

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Wibke Deisting

Full Text Available Bispecific T cell engager (BiTE® are single-chain bispecific antibody constructs with dual specificity for CD3 on T cells and a surface antigen on target cells. They can elicit a polyclonal cytotoxic T cell response that is not restricted by T cell receptor (TCR specificity, and surface expression of MHC class I/peptide antigen complexes. Using human EpCAM/CD3-bispecific BiTE® antibody construct AMG 110, we here assessed to what extent surface expression of PD-L1, cytoplasmic expression of indoleamine-2,3-deoxygenase type 1, Bcl-2 and serpin PI-9, and the presence of transforming growth factor beta (TGF-β, interleukin-10 (IL-10 and adenosine in culture medium can impact redirected lysis by AMG 110-engaged T cells.The seven factors, which are all involved in inhibiting T cell functions by cancer cells, were tested with human EpCAM-expressing Chinese hamster ovary (CHO target cells at levels that in most cases exceeded those observed in a number of human cancer cell lines. Co-culture experiments were used to determine the impact of the evasion mechanisms on EC50 values and amplitude of redirected lysis by AMG 110, and on BiTE®-induced proliferation of previously resting human peripheral T cells.An inhibitory effect on redirected lysis by AMG 110-engaged T cells was seen upon overexpression of serpin PI-9, Bcl-2, TGF-β and PD-L1. An inhibitory effect on induction of T cell proliferation was only seen with CHO cells overexpressing IDO. In no case, a single evasion mechanism rendered target cells completely resistant to BiTE®-induced lysis, and even various combinations could not.Our data suggest that diverse mechanisms employed by cancer cells to fend off T cells cannot inactivate AMG 110-engaged T cells, and that inhibitory effects observed in vitro may be overcome by increased concentrations of the BiTE® antibody construct.

Impact of Diverse Immune Evasion Mechanisms of Cancer Cells on T Cells Engaged by EpCAM/CD3-Bispecific Antibody Construct AMG 110

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Deisting, Wibke; Raum, Tobias; Kufer, Peter; Baeuerle, Patrick A.; Münz, Markus

2015-01-01

Background Bispecific T cell engager (BiTE®) are single-chain bispecific antibody constructs with dual specificity for CD3 on T cells and a surface antigen on target cells. They can elicit a polyclonal cytotoxic T cell response that is not restricted by T cell receptor (TCR) specificity, and surface expression of MHC class I/peptide antigen complexes. Using human EpCAM/CD3-bispecific BiTE® antibody construct AMG 110, we here assessed to what extent surface expression of PD-L1, cytoplasmic expression of indoleamine-2,3-deoxygenase type 1, Bcl-2 and serpin PI-9, and the presence of transforming growth factor beta (TGF-β), interleukin-10 (IL-10) and adenosine in culture medium can impact redirected lysis by AMG 110-engaged T cells. Methods The seven factors, which are all involved in inhibiting T cell functions by cancer cells, were tested with human EpCAM-expressing Chinese hamster ovary (CHO) target cells at levels that in most cases exceeded those observed in a number of human cancer cell lines. Co-culture experiments were used to determine the impact of the evasion mechanisms on EC50 values and amplitude of redirected lysis by AMG 110, and on BiTE®-induced proliferation of previously resting human peripheral T cells. Findings An inhibitory effect on redirected lysis by AMG 110-engaged T cells was seen upon overexpression of serpin PI-9, Bcl-2, TGF-βand PD-L1. An inhibitory effect on induction of T cell proliferation was only seen with CHO cells overexpressing IDO. In no case, a single evasion mechanism rendered target cells completely resistant to BiTE®-induced lysis, and even various combinations could not. Conclusions Our data suggest that diverse mechanisms employed by cancer cells to fend off T cells cannot inactivate AMG 110-engaged T cells, and that inhibitory effects observed in vitro may be overcome by increased concentrations of the BiTE® antibody construct. PMID:26510188

Intracellular Targeting of CEA Results in Th1-Type Antibody Responses Following Intradermal Genetic Vaccination by a Needle-Free Jet Injection Device

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Susanne Johansson

2007-01-01

Full Text Available The route and method of immunization, as well as the cellular localization of the antigen, can influence the generation of an immune response. In general, intramuscular immunization results in Th1 responses, whereas intradermal delivery of DNA by gene gun immunization often results in more Th2 responses. Here we investigate how altering the cellular localization of the tumor antigen CEA (carcinoembryonic antigen affects the quality and amplitude of DNA vaccine-induced antibody responses in mice following intradermal delivery of DNA by a needle-free jet injection device (Biojector. CEA was expressed either in a membrane-bound form (wild-type CEA or in two truncated forms (CEA6 and CEA66 with cytoplasmic localization, where CEA66 was fused to a promiscuous T-helper epitope from tetanus toxin. Repeated intradermal immunization of BALB/c mice with DNA encoding wild-type CEA produced high antibody titers of a mixed IgG1/IgG2a ratio. In contrast, utilizing the DNA construct that resulted in intracellular targeting of CEA led to a reduced capacity to induce CEA-specific antibodies, but instead induced a Th1-biased immune response.

Liver myeloid-derived suppressor cells expand in response to liver metastases in mice and inhibit the anti-tumor efficacy of anti-CEA CAR-T

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Burga, Rachel A.; Thorn, Mitchell; Point, Gary R.; Guha, Prajna; Nguyen, Cang T.; Licata, Lauren A.; DeMatteo, Ronald P.; Ayala, Alfred; Espat, N. Joseph; Junghans, Richard P.; Katz, Steven C.

2015-01-01

Chimeric antigen receptor modified T cell (CAR-T) technology, a promising immunotherapeutic tool, has not been applied specifically to treat liver metastases (LM). While CAR-T delivery to LM can be optimized by regional intrahepatic infusion, we propose that liver CD11b+Gr-1+ myeloid-derived suppressor cells (L-MDSC) will inhibit the efficacy of CAR-T in the intrahepatic space. We studied anti-CEA CAR-T in a murine model of CEA+ LM and identified mechanisms through which L-MDSC expand and inhibit CAR-T function. We established CEA+ LM in mice and studied purified L-MDSC and responses to treatment with intrahepatic anti-CEA CAR-T infusions. L-MDSC expanded three-fold in response to LM and their expansion was dependent on GM-CSF, which was produced by tumor cells. L-MDSC utilized PD-L1 to suppress anti-tumor responses through engagement of PD-1 on CAR-T. GM-CSF, in cooperation with STAT3, promoted L-MDSC PD-L1 expression. CAR-T efficacy was rescued when mice received CAR-T in combination with MDSC depletion, GM-CSF neutralization to prevent MDSC expansion, or PD-L1 blockade. As L-MDSC suppressed anti-CEA CAR-T, infusion of anti-CEA CAR-T in tandem with agents targeting L-MDSC is a rational strategy for future clinical trials. PMID:25850344

FcγRII-binding Centyrins mediate agonism and antibody-dependent cellular phagocytosis when fused to an anti-OX40 antibody.

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Zhang, Di; Whitaker, Brian; Derebe, Mehabaw G; Chiu, Mark L

2018-04-01

Immunostimulatory antibodies against the tumor necrosis factor receptors (TNFR) are emerging as promising cancer immunotherapies. The agonism activity of such antibodies depends on crosslinking to Fc gamma RIIB receptor (FcγRIIB) to enable the antibody multimerization that drives TNFR activation. Previously, Fc engineering was used to enhance the binding of such antibodies to Fcγ receptors. Here, we report the identification of Centyrins as alternative scaffold proteins with binding affinities to homologous FcγRIIB and FcγRIIA, but not to other types of Fcγ receptors. One Centyrin, S29, was engineered at distinct positions of an anti-OX40 SF2 antibody to generate bispecific and tetravalent molecules named as mAbtyrins. Regardless of the position of S29 on the SF2 antibody, SF2-S29 mAbtyrins could bind FcγRIIB and FcγRIIA specifically while maintaining binding to OX40 receptors. In a NFκB reporter assay, attachment of S29 Centyrin molecules at the C-termini, but not the N-termini, resulted in SF2 antibodies with increased agonism owing to FcγRIIB crosslinking. The mAbtyrins also showed agonism in T-cell activation assays with immobilized FcγRIIB and FcγRIIA, but this activity was confined to mAbtyrins with S29 specifically at the C-termini of antibody heavy chains. Furthermore, regardless of the position of the molecule, S29 Centyrin could equip an otherwise Fc-silent antibody with antibody-dependent cellular phagocytosis activity without affecting the antibody's intrinsic antibody-dependent cell-meditated cytotoxicity and complement-dependent cytotoxicity. In summary, the appropriate adoption FcγRII-binding Centyrins as functional modules represents a novel strategy to engineer therapeutic antibodies with improved functionalities.

Anti-carbamylated Protein Antibody Levels Correlate with Anti-Sa (Citrullinated Vimentin) Antibody Levels in Rheumatoid Arthritis.

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Challener, Gregory J; Jones, Jonathan D; Pelzek, Adam J; Hamilton, B JoNell; Boire, Gilles; de Brum-Fernandes, Artur José; Masetto, Ariel; Carrier, Nathalie; Ménard, Henri A; Silverman, Gregg J; Rigby, William F C

2016-02-01

The presence of anticitrullinated protein antibodies (ACPA) in rheumatoid arthritis (RA) indicates a breach in immune tolerance. Recent studies indicate that this breach extends to homocitrullination of lysines with the formation of anti-carbamylated protein (anti-CarP) antibodies. We analyzed the clinical and serologic relationships of anti-CarP in 2 RA cohorts. Circulating levels of immunoglobulin G anti-CarP antibodies were determined by ELISA in established (Dartmouth-Hitchcock Medical Center) and early (Sherbrooke University Hospital Center) cohorts and evaluated for anticyclic citrullinated peptide antibodies (anti-CCP), specific ACPA, and rheumatoid factor (RF) levels using the Student t test and correlation analysis. We identified elevated anti-CarP antibodies titers in 47.0% of seropositive patients (Dartmouth, n = 164), with relationships to anti-CCP (p < 0.0001) and IgM-RF (p = 0.001). Similarly, 38.2% of seropositive patients from the Sherbrooke cohort (n = 171) had elevated anti-CarP antibodies; titers correlated to anti-CCP (p = 0.01) but not IgM-RF (p = 0.09). A strong correlation with anti-Sa was observed: 47.9% anti-Sa+ patients were anti-CarP antibodies+ versus only 25.4% anti-Sa- in the Sherbrooke cohort (p = 0.0002), and 62.6% anti-Sa+ patients versus 26.9% anti-Sa- were anti-CarP antibodies+ in Dartmouth (p < 0.0001). We found a more variable response for reactivity to citrullinated fibrinogen or to citrullinated peptides from fibrinogen and α enolase. In 2 North American RA cohorts, we observed a high prevalence of anti-CarP antibody positivity. We also describe a surprising and unexpected association of anti-CarP with anti-Sa antibodies that could not be explained by cross-reactivity. Further, considerable heterogeneity exists between anti-CarP reactivity and other citrullinated peptide reactivity, raising the question of how the pathogenesis of antibody responses for carbamylated proteins and citrullinated proteins may be linked in vivo.

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

In vivo tumor targeting and imaging with engineered trivalent antibody fragments containing collagen-derived sequences.

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Angel M Cuesta

Full Text Available There is an urgent need to develop new and effective agents for cancer targeting. In this work, a multivalent antibody is characterized in vivo in living animals. The antibody, termed "trimerbody", comprises a single-chain antibody (scFv fragment connected to the N-terminal trimerization subdomain of collagen XVIII NC1 by a flexible linker. As indicated by computer graphic modeling, the trimerbody has a tripod-shaped structure with three highly flexible scFv heads radially outward oriented. Trimerbodies are trimeric in solution and exhibited multivalent binding, which provides them with at least a 100-fold increase in functional affinity than the monovalent scFv. Our results also demonstrate the feasibility of producing functional bispecific trimerbodies, which concurrently bind two different ligands. A trimerbody specific for the carcinoembryonic antigen (CEA, a classic tumor-associated antigen, showed efficient tumor targeting after systemic administration in mice bearing CEA-positive tumors. Importantly, a trimerbody that recognizes an angiogenesis-associated laminin epitope, showed excellent tumor localization in several cancer types, including fibrosarcomas and carcinomas. These results illustrate the potential of this new antibody format for imaging and therapeutic applications, and suggest that some laminin epitopes might be universal targets for cancer targeting.

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

Clinical experience of the radioimmunoscintigraphy with the 123-I-anti-CEA-Fab(No. 35)-fragment

International Nuclear Information System (INIS)

Meili, A.; Bekier, A.; Schulthess, G.K. von; Mach, J.P.

1986-01-01

Purified monoclonal murine 123-I-Fab-anti-CEA(Nr.35) were applied to 7 patients in a prospective study. Compared with the previous tested intact 131-I-labelled antibody (Nr. 202) the new preparation had many advantages for imaging: 2.7 times more counting efficiency of the gamma camera, higher activity utilizable and better accumulation in the tumor with sufficient image contrast in the ECT. Fifteen until sixteen hours after administration of 20 mCi 123-I the countrate in the pelvis was 130000/20 sec. In all patients the primary tumor was visualized, two patients demonstrated regional lymph node involvement and one patient liver metastasis in the left lobe. All findings were confirmed by surgery and histopathology. The average tumor/mucosa ratio was 3.5:1. The activity in the tumor 15 h after application was 0.015 per cent/g tumor/mCi 123-I used. 4/7 patients with colorectal cancer over 3.5 cm in diameter demonstrated normal plasma values of CEA < 3 microg/l. One patient with rising CEA plasma level was suspected of relapse, the focal accumulation corresponded with a mass lesion in the right sacrum in CT-scan. After the preliminary results the further applicability is recognizable: staging and screening before and after therapy, handicapped by high costs at time. A good advantage is the possibility of specific and organ independent diagnosis of tumor, which contents the corresponding surface antigen. (author)

Anti-smooth muscle antibody

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... gov/ency/article/003531.htm Anti-smooth muscle antibody To use the sharing features on this page, please enable JavaScript. Anti-smooth muscle antibody is a blood test that detects the presence ...

Detection of anti-lactoferrin antibodies and anti-myeloperoxidase antibodies in autoimmune hepatitis: a retrospective study.

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Tan, Liming; Zhang, Yuhong; Peng, Weihua; Chen, Juanjuan; Li, Hua; Ming, Feng

2014-01-01

Anti-lactoferrin antibodies (ALA) and anti-myeloperoxidase antibodies (AMPA) are specific serological markers for autoimmune hepatitis (AIH). The project aimed to detect ALA and AMPA and explore their clinical significances in AIH patients. 59 AIH patients, 217 non AIH patients, and 50 healthy controls were enrolled in this study. ALA and AMPA were detected by ELISA. Antineutropil cytoplasmic antibodies (ANCA) and anti-smooth muscle antibodies (ASMA) were examined by indirect immunofluorescence. Antimitochondrial antibody M2 subtype (AMA-M2), anti-liver kidney microsomal antibody Type 1 (LKM1), anti-liver cytosol antibody Type 1 (LC1), and anti-soluble liver antigen/liver-pancreas antibodies (SLA/LP) were tested by immunoblot. The positivity for ALA was 18.6% in AIH group, only one patient in non-AIH group was positive for ALA; the positivity for AMPA was 59.3% in AIH group, with significant differences (P < 0.01) compared with other groups. The specificities for ALA and AMPA were 99.63% and 97.75%; the sensitivities were 18.64% and 59.32%; and the accuracy rates were 84.97% and 90.80%, respectively. A certain correlation was observed between ALA and SLA/LP, AMPA and ANCA, ASMA in AIH group. ALA and AMPA were associated with AIH, and had high clinical diagnostic value. Co-detection with other relative autoantibodies could play an important role in differential diagnosis of AIH.

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.)

The biodistribution and pretargeting radioimmunoimaging of the fusion protein of anti-CEA single-chain antibody and core-streptavidin in human rectocolonic tumor bearing nude mice

International Nuclear Information System (INIS)

Yang Weidong; Li Biao; Zhu Chengmo; Jiang Xufeng; Feng Guowei; Wu Xiangpu

2002-01-01

Objective: To investigate the biodistribution and two-step pretargeting radioimmunoimaging of the fusion protein of anti-carcinoembryonic antigen (CEA) single-chain antibody (ScFv) and core-streptavidin in human rectocolonic tumor bearing nude mice. Methods: Before the injection of 153 Sm-biotin, the fusion protein of ScFv-core-streptavidin was pretargeted for 24 h (200 μg every nude mouse), 24 h later 153 Sm-biotin was injected. The uptake of radioactivity in tumor and normal tissues in 20 nude mice was measured at 1, 4, 8 and 24 h and the other 3 nude mice was scanned at 8 and 24 h after peritoneal injection of 153 Sm-biotin. Results: The tumor to blood ratio (tumor/blood) reached 0.49 , 1.21, 1.56 and 3.09 at 1, 4, 8 and 24 h respectively. Radioactivity concentration peaked at 8 h in tumor site and demonstrated a 'hot' area, with significant decreasing its background at 24 h. Conclusion: The fusion protein can elevate the tumor/blood ratio, shorten pretargeting and imaging process and also improve image quality

Tandem bispecific neutralizing antibody eliminates HIV-1 infection in humanized mice.

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Wu, Xilin; Guo, Jia; Niu, Mengyue; An, Minghui; Liu, Li; Wang, Hui; Jin, Xia; Zhang, Qi; Lam, Ka Shing; Wu, Tongjin; Wang, Hua; Wang, Qian; Du, Yanhua; Li, Jingjing; Cheng, Lin; Tang, Hang Ying; Shang, Hong; Zhang, Linqi; Zhou, Paul; Chen, Zhiwei

2018-04-23

The discovery of an HIV-1 cure remains a medical challenge because the virus rebounds quickly after the cessation of combination antiretroviral therapy (cART). Here, we investigate the potential of an engineered tandem bispecific broadly neutralizing antibody (bs-bnAb) as an innovative product for HIV-1 prophylactic and therapeutic interventions. We discovered that by preserving 2 single-chain variable fragment (scFv) binding domains of each parental bnAb, a single gene-encoded tandem bs-bnAb, BiIA-SG, displayed substantially improved breadth and potency. BiIA-SG neutralized all 124 HIV-1-pseudotyped viruses tested, including global subtypes/recombinant forms, transmitted/founder viruses, variants not susceptible to parental bnAbs and to many other bnAbs with an average IC50 value of 0.073 μg/ml (range HIV-1 stains. Moreover, whereas BiIA-SG delayed viral rebound in a short-term therapeutic setting when combined with cART, a single injection of adeno-associated virus-transferred (AAV-transferred) BiIA-SG gene resulted dose-dependently in prolonged in vivo expression of BiIA-SG, which was associated with complete viremia control and subsequent elimination of infected cells in humanized mice. These results warrant the clinical development of BiIA-SG as a promising bs-bnAb-based biomedical intervention for the prevention and treatment of HIV-1 infection.

Immunological comparison of ovarian and colonic CEA

International Nuclear Information System (INIS)

Burtin, P.; Gendron, M.C.; Maunoury, M.T.; Lamerz, R.; Schnabel, G.

1982-01-01

Ovarian and colonic CEA were compared immunologically by means of antisera prepared against each of them. CEAs of both origins were found identical by immunodiffusion methods. In radioimmunological experiments, slight differences were observed between some but not all ovarian CEAs and colonic CEAs and also between different preparations of colonic CEA: no organ specificity of ovarian CEA could be demonstrated. Finally, CEA level was measured in 41 sera of patients with ovarian carcinoma by two radioimmunoassays, one using colonic CEA as tracer and standard and anti-colonic CEA serum, the other using ovarian CEA and anti-ovarian CEA serum: the values given by the two assays were highly correlated (rsub(s) = 0.8107), meaning that an organ specific assay for ovarian CEA is not needed. (Auth.)

The pharmacological efficacy of the anti-IL17 scFv and sTNFR1 bispecific fusion protein in inflammation mouse stimulated by LPS.

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Yang, Yongbi; Zhang, Teng; Cao, Hongxue; Yu, Dan; Zhang, Tong; Zhao, Shaojuan; Jing, Xiaohui; Song, Liying; Liu, Yunye; Che, Ruixiang; Liu, Xin; Li, Deshan; Ren, Guiping

2017-08-01

Acute lung injury (ALI) is still a leading cause of morbidity and mortality in critically ill patients. Recently, our study found that a bispecific fusion protein treatment can ameliorate the lung injury induced by LPS. However, the molecular mechanisms which bispecific fusion protein ameliorates acute lung injury remain unclear. In this study, we found that the bispecific fusion protein treatment inhibited the nuclear transcription of NF-κB in confocal laser scanning fluorescence microscopy, the bispecific fusion protein exert protective effects in the cell model of ALI induced by lipopolysaccharide (LPS) via inhibiting the nuclear factor κB (NF-κB) signaling pathway and mediate inflammation. Moreover, the treatment of the bispecific fusion protein show its efficacy in animal models stimulated by LPS, the results of real-time PCR and ELISA demonstrate that bispecific fusion protein treatment effectively inhibited the over-expression of inflammatory cytokines(tumor necrosis factor α, interleukin 1β and interleukin 17). In addition, LPS-challenged mice exhibited significant lung injury characterized by the deterioration of histopathology, which was meliorated by bispecific fusion protein treatment. Collectively, these results demonstrate that bispecific fusion protein treatment ameliorates LPS-induced ALI through reducing inflammatory cytokines and lung inflammation, which may be associated with the decreased the nuclear transcription of NF-κB. The bispecific fusion protein may be useful as a novel therapy to treat ALI. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

[Study of anti-idiotype antibodies to human monoclonal antibody].

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Harada, R; Takahashi, N; Owaki, I; Kannagi, R; Endo, N; Morita, N; Inoue, M

1992-02-01

A human monoclonal antibody, ll-50 (IgM, lambda), was generated, which reacted specifically with a major of glycolipid present in LS174T colon cancer cells. The glycolipid antigen which reacted with the ll-50 antibody was expected to four sugar residues from its TLC mobility, and it was ascertained that the glycolipid antigen which reacted with ll-50 antibody might be Lc4 antigen [Gal beta 1----3 GLcNAc beta 1----3 Gal beta 1----4 Glc beta 1----1 Cer] judging from TLC immunostaining and ELISA when the reactivity of ll-50 antibody was tested using various pure glycolipids in 3-5 sugar residues as an antigen. Sera in patients with malignant disorders and healthy individuals were analyzed by Sandwich assay of immobilized and biotinylated ll-50 antibody. The serum of the Lc4 antigen recognized by ll-50 antibody was significantly higher in patients with malignant disorders than that in healthy individuals (p less than 0.05). Three mouse monoclonal anti-idiotype antibodies, G3, B3 and C5 (all IgG1), were generated by the immunization of BALB/c mice with ll-50 antibody. These anti-idiotype antibodies specifically bound to to human monoclonal antibody, ll-50 and had a significant inhibitory activity towards the binding of ll-50 antibody to the Lc4 antigen. This indicated that these anti-idiotype antibodies, G3, B3, and C5, were paratope-related anti-idiotype antibodies. G3, B3, and C5 were expected to define the nearest idiotope because they could mutually inhibit ll-50 antibody. Sera in patients with malignant disorders and healthy individuals were analyzed by Sandwich assay of immobilized and biotinylated anti-idiotype antibodies, G3, B3, and C5. As to the ll-50 like antibodies defined by C5 (Id-C5+), the mean serum level in patients with malignant disorders was significantly higher than that in healthy individuals (p less than 0.05). As to the ll-50 like antibodies defined by B3 (Id-B3+), the mean serum level in patients with malignant disorders was significantly higher

Clinical utility of immunoscintigraphy with the Immu-4 99mTc-Fab' antibody

International Nuclear Information System (INIS)

Moffat, F.L.; Pinsky, C.M.; Hammershaimb, L.; Petrelli, N.J.; Patt, Y.Z.; Whaley, F.S.; Goldenberg, D.M.

1996-01-01

The purpose of these prospective, pivotal studies was to assess the performance and the potential clinical impact of a new antibody imaging agent, CEA-Scan TM , in 210 pre-surgical patients with advanced recurrent or metastatic colorectal carcinomas. CEA-Scan TM , an anti-carcinoembryonic antigen (CEA) Fab' antibody fragment labeled with 99m Tc, was injected IV and external scintigraphy performed 2-5 h and 18-24 h later. Imaging with conventional diagnostic modalities (CDM) was also performed, and findings were confirmed by surgery and histology. The sensitivity of CEA-Scan TM was superior to that of CDM in the extrahepatic abdomen (55 % vs 32 %, ρ 0,007) and pelvis (69 % vs 48 %, p = 0,005), and CEA-Scan TM findings complemented those of CDM in the liver. Among 122 patients with known disease, the positive predictive value was significantly higher when both modalities were positive (98 %) as compared to each alone (68 % - 70 %), potentially obviating the need for histological confirmation when both tests are positive. Imaging accuracy also was significantly improved y adding CEA-Scan TM to CDM. In 88 patients with occult cancer, imaging accuracy was enhanced significantly by CEA-Scan TM combined with CDM (61 % vs 33 %). Potential clinical benefit from CEA-Scan TM was demonstrated in 89 of 210 patients. Only two patients developed human anti-mouse antibodies (HAMA) to CEA-Scan TM after a single injection, and none of 19 assessable patients after two injections. (author)

Introduction to the CEA family: structure, function and secretion.

Science.gov (United States)

Von Kleist, S

1992-01-01

Due to the phenomenal progress in the field of tumor immunology that took place during the last twenty years, we dispose today of highly specific and sensitive techniques and reagents like monoclonal antibodies (MAbs). In this context the discovery in human carcinomas of tumor-associated antigens, such as CEA, was of primary importance, especially since the latter was found to have clinical relevance as a tumor marker. Based on animal models, a new in vivo technology for the detection of tumors and metastases was developed in recent years, that uses anti-CEA MAbs, or fragments of them, coupled to radio-isotopes. This technique, called radio-immunodetection (RAID), also paved the way for immunotherapeutic procedures, where again CEA served as the target-antigen. This new technique holds great promise, provided the epitope-specificity of the MAbs is well-controlled: it has been shown that CEA belongs to a large gene-family of at least 22 members, which can be subdivided into two subgroups (i.e., the CEA- and the PSG-subgroup) and which in turn belongs to the immunoglobulin-supergene family. Great structural similarities render the distinction of the various cross-reactive molecules by immunological means rather difficult.

Preclinical evaluation of multistep targeting of diasialoganglioside GD2 using a IgG-scFv bispecific antibody with high affinity for GD2 and DOTA metal complex

Science.gov (United States)

Cheal, Sarah M.; Xu, Hong; Guo, Hong-fen; Zanzonico, Pat B.; Larson, Steven M.; Cheung, Nai-Kong

2014-01-01

Bispecific antibodies (BsAb) have proven to be useful targeting vectors for pretargeted radioimmunotherapy (PRIT). We sought to overcome key PRIT limitations such as high renal radiation exposure and immunogenicity (e.g. of streptavidin-antibody fusions), to advance clinical translation of this PRIT strategy for diasialoganglioside GD2-positive (GD2(+)) tumors. For this purpose, a IgG-scFv BsAb was engineered using the sequences for the anti-GD2 humanized monoclonal antibody hu3F8 (1) and C825, a murine scFv antibody with high affinity for the chelator 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) complexed with beta-particle emitting radiometals such as 177Lu and 90Y (2, 3). A three-step regimen including hu3F8-C825, a dextran-based clearing agent, and p-aminobenzyl-DOTA radiolabeled with 177Lu (as 177Lu-DOTA-Bn; t1/2 = 6.71 days (d)) was optimized in immunocompromised mice carrying subcutaneous (s.c.) human GD2(+) neuroblastoma (NB) xenografts. Absorbed doses for tumor and normal tissues were ∼85 cGy/MBq and ≤3.7 cGy/MBq, respectively, with therapeutic indicies (TI) of 142 for blood and 23 for kidney. A therapy study (n = 5 per group; tumor volume: 240 ± 160 mm3) with three successive PRIT cycles (total 177Lu: ∼33 MBq; tumor dose ∼3400 cGy), revealed complete tumor response in 5/5 animals, with no recurrence up to 28 d post-treatment. Tumor ablation was confirmed histologically in 4/5 mice, and normal organs showed minimal overall toxicities. All non-treated mice required sacrifice within 12 d (>1.0 cm3 tumor volume). We conclude that this novel anti-GD2 PRIT approach has sufficient TI to successfully ablate s.c. GD2(+)–NB in mice while sparing kidney and bone marrow. PMID:24944121

The Development of Bispecific Hexavalent Antibodies as a Novel Class of DOCK-AND-LOCKTM (DNLTM Complexes

Directory of Open Access Journals (Sweden)

Chien-Hsing Chang

2013-05-01

Full Text Available The DOCK-AND-LOCKTM (DNLTM method provides a modular approach to develop multivalent, multifunctional complexes of defined structures, of which bispecific hexavalent antibodies (bsHexAbs are prominent examples with potential applications in targeted therapy for malignant, autoimmune, and infectious diseases. Currently, bsHexAbs are constructed by derivatizing a divalent IgG, at the carboxyl termini of either the heavy chain (the CH3-format or the light chain (the Ck-format, to contain two stabilized dimers of Fab having a different specificity from the IgG. In this review, we briefly outline the features of the DNLTM method and describe key aspects of bsHexAbs examined with diverse preclinical studies, which include binding affinity to target cells, induction of signaling pathways, effector functions, serum stability, pharmacokinetics, and antitumor activity in human tumor xenograft models. Our findings favor the selection of the CK- over the CH3-format for further exploration of bsHexAbs in clinical trials.

Anti-idiotypes against a monoclonal anti-haloperidol antibody bind to dopamine receptor

International Nuclear Information System (INIS)

Elazar, Z.; Kanety, H.; Schreiber, M.; Fuchs, S.

1988-01-01

Anti-idiotypic antibodies were raised in rabbits by immunization with a monoclonal anti-haloperidol antibody. Some of these anti-idiotypic antibodies bind in a concentration dependent manner to bovine striatal membranes. Following affinity purification, these antibodies inhibit haloperidol binding to striatal membranes and deplete [ 3 H]-spiperone binding sites from a solubilized preparation of striatal membranes. It is thus concluded that these anti-idiotypic antibodies are an internal image of haloperidol and as such can interact with D 2 -dopamine receptors

Construction and characterization of a bispecific diabody for retargeting T cells to human carcinomas

NARCIS (Netherlands)

Helfrich, Wijnand; Kroesen, Bart-Jan; Roovers, R.C; Westers, L; Molema, Ingrid; Hoogenboom, H.R; de Leij, Lou

1998-01-01

We describe the construction of a recombinant bispecific antibody fragment in the diabody format with specificity for both the well-established human pancarcinoma associated target antigen EGP2 (epithelial glycoprotein 2, also known as the CO 17-1A antigen or KSA) and the CD3 epsilon chain of human

Humanised IgG1 antibody variants targeting membrane-bound carcinoembryonic antigen by antibody-dependent cellular cytotoxicity and phagocytosis.

Science.gov (United States)

Ashraf, S Q; Umana, P; Mössner, E; Ntouroupi, T; Brünker, P; Schmidt, C; Wilding, J L; Mortensen, N J; Bodmer, W F

2009-11-17

The effect of glycoengineering a membrane specific anti-carcinoembryonic antigen (CEA) (this paper uses the original term CEA for the formally designated CEACAM5) antibody (PR1A3) on its ability to enhance killing of colorectal cancer (CRC) cell lines by human immune effector cells was assessed. In vivo efficacy of the antibody was also tested. The antibody was modified using EBNA cells cotransfected with beta-1,4-N-acetylglucosaminyltransferase III and the humanised hPR1A3 antibody genes. The resulting alteration of the Fc segment glycosylation pattern enhances the antibody's binding affinity to the FcgammaRIIIa receptor on human immune effector cells but does not alter the antibody's binding capacity. Antibody-dependent cellular cytotoxicity (ADCC) is inhibited in the presence of anti-FcgammaRIII blocking antibodies. This glycovariant of hPR1A3 enhances ADCC 10-fold relative to the parent unmodified antibody using either unfractionated peripheral blood mononuclear or natural killer (NK) cells and CEA-positive CRC cells as targets. NK cells are far more potent in eliciting ADCC than either freshly isolated monocytes or granulocytes. Flow cytometry and automated fluorescent microscopy have been used to show that both versions of hPR1A3 can induce antibody-dependent cellular phagocytosis (ADCP) by monocyte-derived macrophages. However, the glycovariant antibody did not mediate enhanced ADCP. This may be explained by the relatively low expression of FcgammaRIIIa on cultured macrophages. In vivo studies show the efficacy of glycoengineered humanised IgG1 PR1A3 in significantly improving survival in a CRC metastatic murine model. The greatly enhanced in vitro ADCC activity of the glycoengineered version of hPR1A3 is likely to be clinically beneficial.

Purification of immunoreactive radiolabeled moniclonal antibodies with anti-iodiotypic moniclonal antibodies

International Nuclear Information System (INIS)

Temponi, M.; Pupa, S.; Ferrone, S.

1990-01-01

A method is described to purify immunoreactive moniclonal antibodies from radiolabeled monoclonal antibody preparations. The method is based on incubation of radiolabeled monoclonal antibodies with insolubilized anti-idiotypic monoclonal antibodies to idiotopes within the antigen-combining site of monoclonal antibodies to be purified an elution of bound monoclonal antibodies with a low pH buffer. The immunoreactive fraction of the purified monoclonal antibodies was at least 82%; the yeald was at least 73%. The purification procedure did not cause any detectable change in the affinity constant of the eluted monoclonal antibodies. The method is simple and rapid; the requirement for anti-idiotypic monoclonal antibodies to idiotopes within the antigen-combining site of the antibodies to be purified is not likely to represent a major limitation in the broad application of the present method, since the hybridoma technology has greatly facilitated the development of anti-idiotypic monoclonal antibodies. (author). 12 refs.; 4 figs.; 1 tab

Value of radioimmunoscintigraphy with technetium-99m labelled anti-CEA monoclonal antibody (BW431/26) in the detection of colorectal cancer

International Nuclear Information System (INIS)

Poshyachinda, M.; Chaiwatanarat, T.; Saesow, N.; Thitathan, S.; Voravud, N.

1996-01-01

This study was undertaken as part of a Coordinated Research Programme initiated by the International Atomic Energy Agency to evaluate the usefulness of radioimmunoscintigraphy (RIS) in the management of patients with colorectal cancer. Technetium-99m labelled BW431/26, a monoclonal antibody against cardinoembryonic antigen (CEA) was used. The study included 73 patients (31 females and 42 males). Sixty-eight patients were suspected of having recurrent colorectal adenocarcinoma while another five were suspected to have primary colorectal cancer. Images were acquired at 10 min and 4 and 24 h following the injection of radioantibody. The efficacy of RIS in tumour detection was evaluated by the findings at surgery, histological investigation and/or other diagnostic modalities and clinical follow-up. Four of five patients with suspected primary colorectal cancer gave true-positive results (three at primary sites, one at the site of a metastatic lesion) while one was flase-positive. The overall accuracy of RIS in the diagnosis of recurrent colorectal cancer was 87%. Its sensitivity in the detection of locoregional or abdominal recurrence and liver metastases was 97% and 89% respectively. RIS was more accurate than computed tomography (CT) scan in the detection of pelvic recurrence and liver metastases while CT scan was far superior to RIS in detecting lung metastases. RIS proved most useful in patents who had rising CEA levels on clinical follow-up but in whom other work-up, including CT scan, was negative. The advantages of RIS include the ability to detect tumour recurrence prior to other investigations and to identify tumour recurrence in areas such as the pelvis, where CT and magnetic resonance imaging have their greatest weaknesses in diagnosing recurrent disease. The imaging accuracy is significantly increased when combined CT and antibody imaging is performed. (orig.)

Redirecting T cells to eradicate B-cell acute lymphoblastic leukemia: bispecific T-cell engagers and chimeric antigen receptors.

Science.gov (United States)

Aldoss, I; Bargou, R C; Nagorsen, D; Friberg, G R; Baeuerle, P A; Forman, S J

2017-04-01

Recent advances in antibody technology to harness T cells for cancer immunotherapy, particularly in the difficult-to-treat setting of relapsed/refractory acute lymphoblastic leukemia (r/r ALL), have led to innovative methods for directing cytotoxic T cells to specific surface antigens on cancer cells. One approach involves administration of soluble bispecific (or dual-affinity) antibody-based constructs that temporarily bridge T cells and cancer cells. Another approach infuses ex vivo-engineered T cells that express a surface plasma membrane-inserted antibody construct called a chimeric antigen receptor (CAR). Both bispecific antibodies and CARs circumvent natural target cell recognition by creating a physical connection between cytotoxic T cells and target cancer cells to activate a cytolysis signaling pathway; this connection allows essentially all cytotoxic T cells in a patient to be engaged because typical tumor cell resistance mechanisms (such as T-cell receptor specificity, antigen processing and presentation, and major histocompatibility complex context) are bypassed. Both the bispecific T-cell engager (BiTE) antibody construct blinatumomab and CD19-CARs are immunotherapies that have yielded encouraging remission rates in CD19-positive r/r ALL, suggesting that they might serve as definitive treatments or bridging therapies to allogeneic hematopoietic cell transplantation. With the introduction of these immunotherapies, new challenges arise related to unique toxicities and distinctive pathways of resistance. An increasing body of knowledge is being accumulated on how to predict, prevent, and manage such toxicities, which will help to better stratify patient risk and tailor treatments to minimize severe adverse events. A deeper understanding of the precise mechanisms of action and immune resistance, interaction with other novel agents in potential combinations, and optimization in the manufacturing process will help to advance immunotherapy outcomes in the r

Anti-glucagon antibodies in diabetes mellitus

Energy Technology Data Exchange (ETDEWEB)

Gergely, A; Koranyi, L; Halmos, T; Zsombok, M; Peterfy, F; Csizer, Z; Salamon, F; Tako, J

1973-01-01

Anti-insulin antibodies appear in the sera of patients treated with insulin lastingly. A high anti-insulin antibody level results in the development of insulin resistance. Most of the insulin preparations available on the market contain also glucagon as an impurity. It was therefore to be expected that in part of the patients, who had been treated with insulin lastingly, antibodies would be produced also against glucagon, and the presence of these was actually demonstrated. It is to be assumed that the anti-glucagon antibodies play a role in the pathomechanism of diabetes mellitus, mainly in its labile form. The possible presence of anti-glucagon antibodies must be taken into account when the glucagon concentration in the sera of diabetics is to be determined by means of radioimmunoassay (RIA). The specific antibodies in the serum give false results in the quantitative determination of glucagon. We have tested the sera of 10 diabetics who had been treated with insulin for at least 6 years. All patients were given protamine zinc and crystalline insulin preparations.

Selection of monoclonal anti-CEA antibody fragments for tumor detection by immunoscintigraphy

International Nuclear Information System (INIS)

Mach, J.P.; Buchegger, F.

1986-01-01

It is described how individual MAb directed against carcinoembryotic antigen (CEA) is selected which does not crossreact with granulocytes and gives the best tumor localization in the model of nude mice grafted with human colon carcinoma. Using this model, the superiority of F(ab')/sub 2/ and particularly Fab fragments from high affinity MAb for the localization of relatively small tumor nodules is demonstrated. These MAb fragments are also successfully used in an ongoing clinical trial for the detection of primary and metastatic colorectal carcinomas

Anti-prothrombin antibodies are associated with adverse pregnancy outcome.

Science.gov (United States)

Marozio, Luca; Curti, Antonella; Botta, Giovanni; Canuto, Emilie M; Salton, Loredana; Tavella, Anna Maria; Benedetto, Chiara

2011-11-01

Women with antiphospholipid antibodies (aPL) such as lupus anticoagulant, anticardiolipin antibodies, and anti-β(2) glycoprotein-1 antibodies are at high risk of late pregnancy complications, such as severe pre-eclampsia, placental insufficiency, and fetal loss. It has been observed that aPL consists of a heterogeneous group of antibodies targeting several phospholipid-binding plasma proteins, including also anti-prothrombin (anti-PT), anti-protein S (anti-PS), and anti-protein C (anti-PC) antibodies. Their potential role in late pregnancy complications is not known. The aim of this work was to investigate the association between those autoantibodies and histories for adverse pregnancy outcome. Anti-PT, anti-PS, and anti-PC antibodies were evaluated in 163 patients with previous severe pre-eclampsia, fetal death, and/or placental abruption and in as many women with previous uneventful pregnancies, negative for aPL. The prevalence of anti-PT antibodies was higher in cases than in controls (OR, 95% CI: 10.92, 4.52-26.38). The highest prevalence was observed in subjects with fetal death. Anti-PT antibodies appear to be associated with adverse pregnancy outcome, irrespectively of aPL. © 2011 John Wiley & Sons A/S.

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

Development of a kit lyophilized of Anti-CEA to be labeled with Tc-99m, radionuclide obtained by extraction with MEK, complemented with studies of stability

International Nuclear Information System (INIS)

Robles Nique, Anita E.

2006-01-01

The colorectal cancer places the sixth place in Peru, more than 350 persons are diagnosed annually with this illness, for that reason, the present work contributes with the development of a lyophilized kit of monoclonal antibody Anti-CEA to be labelled by the radionuclide Tc-99m, for the early diagnosis of tumours embryonic adenocarcinoma. For the lack of a generator of adsorption of 99 Mo / 99m Tc in the country, the Tc-99m is used instead of this, coming from a generator of extraction, that use the methylethylketone (MEK) like solvent. First, it was designed systematically 4 lyophilized formulations and through the determination of the radiochemical purity of 99m Tc-Anti-CEA, the effect of the molar relation has been evaluated of the MoAb: 2-ME (1:1000 and 1:2000), the increasing of the reductor agent (3,50 to 5,95 μg SnF2) and the reduced protein (1,0 to 1,2 mg Anti-CEA). Second. On the base of the evaluation of the results of these 4 lyophilized formulations, 4 experimental lots have been prepared. The developed methodology initiates with the reduction of the protein for the direct method with 2-ME, the purification in column of PD10, then the addition of the SnF 2 and MDP, finally the lyophilization. Lyophilized kit is labeled by Tc-99m by the direct method to obtain 99m Tc-Anti-CEA and the radiochemical purity is determined by chromatography in ITLC-SG and HPLC, activity support and volume of Tc-99m, biological distribution in healthy mice, immunoreactivity is determined by chromatography of affinity, challenge with L-cysteine determined by chromatography in ITLC-SG. It complements itself with studies of stability in real-time for the lyophilized kit and for 99m Tc-Anti-CEA. The results of the first part, its 1st; 2nd; 3rd and 4th lyophilized formulation had a radiochemical purity of 71, 92, 94 and 97 % respectively, to a pH of labelled between 7,0 to 7,5. The results of the second part, 4 experimental lots had in average of radiochemical purity more than 95

Anti-microbial antibodies in celiac disease: Trick or treat?

Science.gov (United States)

Papp, Maria; Foldi, Ildiko; Altorjay, Istvan; Palyu, Eszter; Udvardy, Miklos; Tumpek, Judit; Sipka, Sandor; Korponay-Szabo, Ilma Rita; Nemes, Eva; Veres, Gabor; Dinya, Tamas; Tordai, Attila; Andrikovics, Hajnalka; Norman, Gary L; Lakatos, Peter Laszlo

2009-01-01

AIM: To determine the prevalence of a new set of anti-glycan and anti-outer membrane protein (anti-OMP) antibodies in a Hungarian cohort of adult Celiac disease (CD) patients. METHODS: 190 consecutive CD patients [M/F: 71/119, age:39.9 (SD:14.1) years], 100 healthy, and 48 gastrointestinal controls were tested for glycan anti-Saccharomyces cerevisiae (gASCA), anti-laminaribioside (ALCA), anti-chitobioside, anti-mannobioside, anti-OMP antibodies and major NOD2/CARD15 mutations. Thirty out of 82 CD patients enrolled at the time of diagnosis were re-evaluated for the same antibodies after longstanding gluten-free diet (GFD). RESULTS: 65.9% of the CD patients were positive for at least one of the tested antibodies at the time of the diagnosis. Except anti-OMP and ALCA, anti-microbial antibodies were exclusively seen in untreated CD; however, the overall sensitivity was low. Any glycan positivity (LR+: 3.13; 95% CI: 2.08-4.73) was associated with an increased likelihood ratio for diagnosing CD. Significant correlation was found between the levels of anti-glycan and anti-endomysial or anti-transglutaminase antibodies. Anti-glycan positivity was lost after longstanding GFD. Anti-glycan antibody titers were associated with symptoms at presentation, but not the presence of NOD2/CARD15 mutations. Patients with severe malabsorption more frequently had multiple antibodies at diagnosis (P = 0.019). CONCLUSION: The presence of anti-glycan antibodies in CD seems to be secondary to the impaired small bowel mucosa which can lead to increased antigen presentation. Furthermore, anti-glycan positivity may be considered an additional marker of CD and dietary adherence. PMID:19701969

A new solid phase enzyme immuno assay using a monoclonal antibody for CEA determinations in patients with various carcinomas

International Nuclear Information System (INIS)

Staab, H.J.; Glock, S.; Hornung, A.

1982-01-01

The clinical validity of carcinoembryonic antigen (CEA) determination with a new solid phase enzyme immuno assay using a monoclonal antibody (EIA-m) in comparison with a common CEA radioimmunoassay with polyclonal antisera (RIA) was investigated for primary diagnosis in 123 patients with various malignancies and in the postoperative followup of 83 patients with gastrointestinal cancers over a period of about one year. The normal range of the new CEA test in which CEA was directly measured without any further extraction, was calculated from the CEA distribution of 147 healthy blood donors and found to be 0-1.5 μg CEA/l. Besides a very fine reproducibility the CEA-m exhibited a pronounced specificity for CEA from patients with colorectal cancers compared with the RIA. Using a cut-off level of >=1.5 μg CEA/l serum with the EIA-m, the test gave a specificity of 76% with a sensitivity of 72% for preoperative serum specimen of 82 patients with colorectal cancers and a control group of 53 patients with nonmalignant gastrointestinal diseases. In this groups of patients the EIA-m was superior to the RIA test which had a sensitivity of 75% at a specificity of 62% using a threshold of >=2.0 μg CEA/l serum. In the followup studies 3 basic tendencies of the CEA time courses well distinguished from each other could be established for both CEA-Tests. Tumor progression, characterized by steadily increasing CEA levels were evident in 20/23 cases with recurrent disease while decreasing or essentially unchanged CEA levels correlated with NED status in the patients. Furthermore 3/23 cases with metastasis in the followup had initial CEA increases indicated by EIA-m, 3-5 months before this increase of the CEA values was evident with the RIA. Transient CEA elevations, not associated with malignant growth, were found less frequently with the new EIA-m compared to the RIA. (orig.) [de

[A spectrum of neurological diseases with anti-VGKC antibody].

Science.gov (United States)

Arimura, Kimiyoshi; Watanabe, Osamu; Nagado, Tatsui

2007-11-01

Anti-VGKC antibody causing peripheral nerve hyperexcitability is already an established clinical entity. Recently, many patients with non-herpetic limbic encephalitis (NHLE) with anti-VGKC antibody have been reported. The characteristic clinical features are low serum Na+ concentration and good response to immunotherapy. Anti-VGK antibody positive NHLE is relatively frequent among immune-mediated NHLE. It is important to know that this disease is responsive to immunotherapy. Furthermore, anti-VGKC antibody is also positive in some intractable epilepsies. These findings suggest that anti-VGKC is correlated with hyperexcitability in both the peripheral and central nervous system and that the spectrum of anti-VGKC antibody syndrome is now expanding.

Targeted immunotherapy in Hodgkin lymphoma

DEFF Research Database (Denmark)

Hutchings, Martin

2015-01-01

In this issue of Blood, Rothe et al introduce a new principle of targeted Hodgkin lymphoma (HL) immunotherapy in their report from a phase 1 study of the bispecific anti-CD30/CD16A antibody construct AFM13.......In this issue of Blood, Rothe et al introduce a new principle of targeted Hodgkin lymphoma (HL) immunotherapy in their report from a phase 1 study of the bispecific anti-CD30/CD16A antibody construct AFM13....

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.)

Anti-influenza M2e antibody

Science.gov (United States)

Bradbury, Andrew M [Santa Fe, NM

2011-12-20

Humanized recombinant and monoclonal antibodies specific for the ectodomain of the influenza virus M2 ion channel protein are disclosed. The antibodies of the invention have anti-viral activity and may be useful as anti-viral therapeutics and/or prophylactic/vaccine agents for inhibiting influenza virus replication and for treating individuals infected with influenza.

CEA in activated macrophages. New diagnostic possibilities for tumor markers in early colorectal cancer.

Science.gov (United States)

Japink, Dennis; Leers, Mathie P G; Sosef, Meindert N; Nap, Marius

2009-08-01

Serum tumor markers show low sensitivity, making them unsuitable for early detection of cancer. Activated macrophages (AM) from peripheral blood can accumulate tumor marker substances and facilitate early detection in prostate cancer. Here it was investigated whether carcinoembryonic antigen (CEA)-containing macrophages (CEACM) can be used to detect colorectal cancer (CRC) at earlier stages than can serum CEA. Peripheral blood was collected from patients with CRC (n=48), inflammatory colorectal disease (n=5) and from healthy controls (n=18). After separating and labeling AM with CD14-APC/CD16-FITC, AM were intracellularly labeled with anti-CEA antibody and flow cytometrically analyzed. Serum CEA and C-reactive protein (CRP) were measured. The fraction-size of CEACM discriminated between controls and CRC patients, irrespective of AJCC stage (AJCC stage I-IV, pCEA values were significantly elevated in AJCC stage II, III and IV (p=0.02, 0.006 and <0.0001, respectively). Combining CEACM with CRP levels separated CRC from inflammatory colorectal disease. CEACM combined with CRP appears to have diagnostic potential in early CRC.

Lack of radioimmunodetection and complications associated with monoclonal anticarcinoembryonic antigen antibody cross-reactivity with an antigen on circulating cells

International Nuclear Information System (INIS)

Dillman, R.O.; Beauregard, J.C.; Sobol, R.E.; Royston, I.; Bartholomew, R.M.; Hagan, P.S.; Halpern, S.E.

1984-01-01

Characterization of several high-affinity murine monoclonal anticarcinoembryonic antigen (CEA) antibodies suggested good specificity except for cross-reactivity with an antigen on granulocytes and erythrocytes which was different from the previously described normal cross-reacting antigen of granulocytes. In vivo studies in athymic mice using an indium conjugate of an anti-CEA monoclonal antibody (MoAb) revealed excellent specific uptake in colorectal carcinoma xenografts. Studies were conducted in humans to determine the limitations produced by the cross-reactivity with granulocytes and erythrocytes. Patients with metastatic colorectal cancer received 3 to 6 mg of anti-CEA MoAb over 10 min or 2 hr. In five of six trials, the MoAb infusion was associated with a 40 to 90% decrease in circulating granulocytes and systemic toxicity including fever, rigors, and emesis. One patient had no change in cell count and had no toxicity. Radionuclide scans with 111 In-anti-CEA MoAb showed marked uptake in the spleen when cells were eliminated, and in the liver, especially when pretreatment CEA levels were high. Metastatic tumor sites failed to concentrate the isotope. This study emphasizes the potential limitations for radioimmunodetection and/or radioimmunotherapy imposed by reactivity with circulating cells, and suggests that certain toxic reactions associated with MoAb infusions are related to destruction of circulating cells rather than allergic reactions to mouse protein. It also emphasizes how variables such as dose and binding affinity of antibody, radioisotope used, and assessment at different observation points can obscure lack of antibody specificity

Lack of radioimmunodetection and complications associated with monoclonal anticarcinoembryonic antigen antibody cross-reactivity with an antigen on circulating cells

Energy Technology Data Exchange (ETDEWEB)

Dillman, R.O.; Beauregard, J.C.; Sobol, R.E.; Royston, I.; Bartholomew, R.M.; Hagan, P.S.; Halpern, S.E.

1984-05-01

Characterization of several high-affinity murine monoclonal anticarcinoembryonic antigen (CEA) antibodies suggested good specificity except for cross-reactivity with an antigen on granulocytes and erythrocytes which was different from the previously described normal cross-reacting antigen of granulocytes. In vivo studies in athymic mice using an indium conjugate of an anti-CEA monoclonal antibody (MoAb) revealed excellent specific uptake in colorectal carcinoma xenografts. Studies were conducted in humans to determine the limitations produced by the cross-reactivity with granulocytes and erythrocytes. Patients with metastatic colorectal cancer received 3 to 6 mg of anti-CEA MoAb over 10 min or 2 hr. In five of six trials, the MoAb infusion was associated with a 40 to 90% decrease in circulating granulocytes and systemic toxicity including fever, rigors, and emesis. One patient had no change in cell count and had no toxicity. Radionuclide scans with /sup 111/In-anti-CEA MoAb showed marked uptake in the spleen when cells were eliminated, and in the liver, especially when pretreatment CEA levels were high. Metastatic tumor sites failed to concentrate the isotope. This study emphasizes the potential limitations for radioimmunodetection and/or radioimmunotherapy imposed by reactivity with circulating cells, and suggests that certain toxic reactions associated with MoAb infusions are related to destruction of circulating cells rather than allergic reactions to mouse protein. It also emphasizes how variables such as dose and binding affinity of antibody, radioisotope used, and assessment at different observation points can obscure lack of antibody specificity.

Sustained Brown Fat Stimulation and Insulin Sensitization by a Humanized Bispecific Antibody Agonist for Fibroblast Growth Factor Receptor 1/βKlotho Complex

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Ganesh Kolumam

2015-07-01

Full Text Available Dissipating excess calories as heat through therapeutic stimulation of brown adipose tissues (BAT has been proposed as a potential treatment for obesity-linked disorders. Here, we describe the generation of a humanized effector-less bispecific antibody that activates fibroblast growth factor receptor (FGFR 1/βKlotho complex, a common receptor for FGF21 and FGF19. Using this molecule, we show that antibody-mediated activation of FGFR1/βKlotho complex in mice induces sustained energy expenditure in BAT, browning of white adipose tissue, weight loss, and improvements in obesity-associated metabolic derangements including insulin resistance, hyperglycemia, dyslipidemia and hepatosteatosis. In mice and cynomolgus monkeys, FGFR1/βKlotho activation increased serum high-molecular-weight adiponectin, which appears to contribute over time by enhancing the amplitude of the metabolic benefits. At the same time, insulin sensitization by FGFR1/βKlotho activation occurs even before the onset of weight loss in a manner that is independent of adiponectin. Together, selective activation of FGFR1/βKlotho complex with a long acting therapeutic antibody represents an attractive approach for the treatment of type 2 diabetes and other obesity-linked disorders through enhanced energy expenditure, insulin sensitization and induction of high-molecular-weight adiponectin.

Cloning and molecular characterization of the cDNAs encoding the variable regions of an anti-CD20 monoclonal antibody.

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Shanehbandi, Dariush; Majidi, Jafar; Kazemi, Tohid; Baradaran, Behzad; Aghebati-Maleki, Leili

2017-01-01

CD20-based targeting of B-cells in hematologic malignancies and autoimmune disorders is associated with outstanding clinical outcomes. Isolation and characterization of VH and VL cDNAs encoding the variable regions of the heavy and light chains of monoclonal antibodies (MAb) is necessary to produce next generation MAbs and their derivatives such as bispecific antibodies (bsAb) and single-chain variable fragments (scFv). This study was aimed at cloning and characterization of the VH and VL cDNAs from a hybridoma cell line producing an anti-CD20 MAb. VH and VL fragments were amplified, cloned and characterized. Furthermore, amino acid sequences of VH, VL and corresponding complementarity-determining regions (CDR) were determined and compared with those of four approved MAbs including Rituximab (RTX), Ibritumomab tiuxetan, Ofatumumab and GA101. The cloned VH and VL cDNAs were found to be functional and follow a consensus pattern. Amino acid sequences corresponding to the VH and VL fragments also indicated noticeable homologies to those of RTX and Ibritumomab. Furthermore, amino acid sequences of the relating CDRs had remarkable similarities to their counterparts in RTX and Ibritumomab. Successful recovery of VH and VL fragments encourages the development of novel CD20 targeting bsAbs, scFvs, antibody conjugates and T-cells armed with chimeric antigen receptors.

Frequently relapsing anti-glomerular basement membrane antibody disease with changing clinical phenotype and antibody characteristics over time

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Gu, Bobby; Magil, Alex B.; Barbour, Sean J.

2016-01-01

Anti-glomerular basement membrane (GBM) antibody disease is a typically monophasic autoimmune disease with severe pulmonary and renal involvement. We report an atypical case of frequently relapsing anti-GBM antibody disease with both anti-GBM antibody?positive flares with pulmonary and renal involvement, and anti-GBM antibody?negative flares that were pulmonary limited with no histologic renal disease. This is the first report of alternating disease phenotype and anti-GBM antibody status over...

Anti-adalimumab antibodies in juvenile idiopathic arthritis-related uveitis.

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Leinonen, Sanna T; Aalto, Kristiina; Kotaniemi, Kaisu M; Kivelä, Tero T

2017-01-01

To evaluate the association of adalimumab trough levels and anti-adalimumab antibodies with activity of uveitis in juvenile idiopathic arthritis-related uveitis. This was a retrospective observational case series in a clinical setting at the Department of Ophthalmology, Helsinki University Hospital, Finland in 2014-2016. Thirty-one paediatric patients with chronic anterior juvenile idiopathic arthritis-related uveitis in 58 eyes and who had been on adalimumab ≥6 months were eligible for the study. Uveitis activity during adalimumab treatment, adalimumab trough levels and anti-adalimumab antibody levels were recorded. Anti-adalimumab antibody levels ≥12 AU /ml were detected in nine patients (29%). This level of anti-adalimumab antibodies was associated with a higher grade of uveitis (puveitis that was not in remission (p=0.001) and with lack of concomitant methotrexate therapy (p=0.043). In patients with anti-adalimumab antibody levels uveitis (p=0.86). Adalimumab treatment might be better guided by monitoring anti-adalimumab antibody formation in treating JIA-related uveitis.

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

Anti-neuronal anti-bodies in patients with early psychosis.

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Mantere, O; Saarela, M; Kieseppä, T; Raij, T; Mäntylä, T; Lindgren, M; Rikandi, E; Stoecker, W; Teegen, B; Suvisaari, J

2018-02-01

It may be challenging to distinguish autoimmune encephalitis associated with anti-neuronal autoantibodies from primary psychiatric disorders. Here, serum was drawn from patients with a first-episode psychosis (n=70) or a clinical high-risk for psychosis (n=6) and controls (n=34). We investigated the serum prevalence of 24 anti-neuronal autoantibodies: IgG antibodies for anti-N-methyl-d-aspartate-type glutamate receptor (anti-NMDAR), glutamate and γ-aminobutyric acid alpha and beta receptors (GABA-a, GABA-b), alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPA), glycine receptor (GlyR), metabotropic glutamate receptor 1 and 5 (mGluR1, mGluR5), anti-Tr/Delta/notch-like epidermal growth factor-related receptor (DNER), contactin-associated protein-like 2 (CASPR2), myelin oligodendrocyte glycoprotein (MOG), glutamic acid decarboxylase-65 (GAD65), collapsin response mediator protein 5/crossveinless-2 (CV2), aquaporin-4 (AQP4), anti-dipeptidyl-peptidase-like protein-6 (DPPX), type 1 anti-neuronal nuclear antibody (ANNA-1, Hu), Ri, Yo, IgLON5, Ma2, zinc finger protein 4 (ZIC4), Rho GTPase-activating protein 26, amphiphysin, and recoverin, as well as IgA and IgM for dopamine-2-receptor (DRD2). Anti-NMDA IgG antibodies were positive with serum titer 1:320 in one patient with a clinical high risk for psychosis. He did not receive a diagnosis of encephalitis after comprehensive neurological evaluation. All other antineuronal autoantibodies were negative and there were no additional findings with immunohistochemistry of brain issues. Copyright © 2017 Elsevier B.V. All rights reserved.

Glutamic acid decarboxylase (anti-GAD & tissue transglutaminase (anti-TTG antibodies in patients with thyroid autoimmunity

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R K Marwaha

2013-01-01

Full Text Available Background & objectives: Several autoimmune disorders have been reported to be associated with autoimmune thyroiditis and may coexist with other organ-specific autoantibodies. The aim of the present study was to evaluate the presence of tissue transglutaminase (anti-TTG and glutamic acid decarboxylase (anti-GAD antibodies in patients suffering from autoimmune thyroiditis as diagnosed by anti-thyroid peroxidase (anti-TPO antibodies, which may indicate high risk for developing celiac disease or type 1 diabetes mellitus. Methods: Five thousand children and 2800 adults were screening as part of a general health examination done on a voluntary basis in four different parts of Delhi. A total of 577 subjects positive for anti-TPO antibody constituted the cases. Equal number of age and sex matched anti-TPO antibody negative controls were randomly selected from the same cohort to form paired case control study. The cases and controls were further divided into two groups as follows: group-1 (children and adolescent 18 yr. Serum samples of cases and controls were analysed for thyroid function test (FT3, FT4, and TSH, anti-TTG and anti-GAD antibodies. Results: A total of 1154 subjects (577 cases and 577 controls were included in this study. Hypothyroidism was present in 40.2 per cent (232 cases compared to only 4.7 per cent (27 in controls (P<0.001. Anti-TTG and anti-GAD antibodies were present in 6.9 and 12.5 per cent subjects among cases compared to 3.5 per cent (P=0.015 and 4.3 per cent (P=0.001 in controls, respectively. Only anti-GAD antibody were significantly positive in cases among children and adolescents (P =0.0044 and adult (P=0.001 compared to controls. Levels of anti-TTG and anti-GAD antibodies increased with increasing titre of anti-TPO antibody. Interpretation & conclusions: Our findings showed high positivity of anti-GAD and anti-TTG antibodies among subjects with thyroid autoimmunity. It is, therefore, important to have high clinical index

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

Novel adenoviral vector induces T-cell responses despite anti-adenoviral neutralizing antibodies in colorectal cancer patients.

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Morse, Michael A; Chaudhry, Arvind; Gabitzsch, Elizabeth S; Hobeika, Amy C; Osada, Takuya; Clay, Timothy M; Amalfitano, Andrea; Burnett, Bruce K; Devi, Gayathri R; Hsu, David S; Xu, Younong; Balcaitis, Stephanie; Dua, Rajesh; Nguyen, Susan; Balint, Joseph P; Jones, Frank R; Lyerly, H Kim

2013-08-01

First-generation, E1-deleted adenovirus subtype 5 (Ad5)-based vectors, although promising platforms for use as cancer vaccines, are impeded in activity by naturally occurring or induced Ad-specific neutralizing antibodies. Ad5-based vectors with deletions of the E1 and the E2b regions (Ad5 [E1-, E2b-]), the latter encoding the DNA polymerase and the pre-terminal protein, by virtue of diminished late phase viral protein expression, were hypothesized to avoid immunological clearance and induce more potent immune responses against the encoded tumor antigen transgene in Ad-immune hosts. Indeed, multiple homologous immunizations with Ad5 [E1-, E2b-]-CEA(6D), encoding the tumor antigen carcinoembryonic antigen (CEA), induced CEA-specific cell-mediated immune (CMI) responses with antitumor activity in mice despite the presence of preexisting or induced Ad5-neutralizing antibody. In the present phase I/II study, cohorts of patients with advanced colorectal cancer were immunized with escalating doses of Ad5 [E1-, E2b-]-CEA(6D). CEA-specific CMI responses were observed despite the presence of preexisting Ad5 immunity in a majority (61.3 %) of patients. Importantly, there was minimal toxicity, and overall patient survival (48 % at 12 months) was similar regardless of preexisting Ad5 neutralizing antibody titers. The results demonstrate that, in cancer patients, the novel Ad5 [E1-, E2b-] gene delivery platform generates significant CMI responses to the tumor antigen CEA in the setting of both naturally acquired and immunization-induced Ad5-specific immunity.

Anti sperm antibodies detection in infertile patients by radioimmunometry

International Nuclear Information System (INIS)

ELnabarawy, F.; Megahed, Y.M.; Tadrous, G.A.; Hamada, T.; Elbadry, A.

1992-01-01

Three different methods of testing for anti sperm antibodies were compared: complement cytotoxicity, sperm agglutination, and radiolabelled anti globulin antibody technique, for detection of anti sperm antibodies in serum and secretions (seminal plasma and cervical mucus). Sample from 120 patients with infertility were investigated by the previous three methods. The results of unexplained infertile patients revealed wide variations in figures, concerning the positivity of anti sperm antibody whether in their serum or secretions, by using the cytotoxicity or sperm agglutination tests. Using a specific radiolabelled anti globulin test, a subset of patients (44.9% in the serum of men and 50% in seminal plasma) with IgG anti sperm antibody was identified, and this antibody was present in 65.4% and 78,6% of infertile wives sera and cervical mucus, respectively. Therefore, this test has been used to identify and quantitate antibodies directed toward other human cell surfaces. It was concluded that this radiolabelled method is a clinically useful and a potentially versatile procedure that can be successfully applied to the diagnosis and management of patients with suspected immunologic infertility. 1 fig., 5 tab

C4d-negative antibody-mediated rejection with high anti-angiotensin II type I receptor antibodies in absence of donor-specific antibodies.

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Fuss, Alexander; Hope, Christopher M; Deayton, Susan; Bennett, Greg Donald; Holdsworth, Rhonda; Carroll, Robert P; Coates, P Toby H

2015-07-01

Acute antibody-mediated rejection can occur in absence of circulating donor-specific antibodies. Agonistic antibodies targeting the anti-angiotensin II type 1 receptor (anti-AT1 R) are emerging as important non-human leucocyte antigen (HLA) antibodies. Elevated levels of anti-angiotensin II receptor antibodies were first observed in kidney transplant recipients with malignant hypertension and allograft rejection. They have now been studied in three separate kidney transplant populations and associate to frequency of rejection, severity of rejection and graft failure. We report 11 cases of biopsy-proven, Complement 4 fragment d (C4d)-negative, acute rejection occurring without circulating donor-specific anti-HLA antibodies. In eight cases, anti-angiotensin receptor antibodies were retrospectively examined. The remaining three subjects were identified from our centre's newly instituted routine anti-angiotensin receptor antibody screening. All subjects fulfilled Banff 2013 criteria for antibody-mediated rejection and all responded to anti-rejection therapy, which included plasma exchange and angiotensin receptor blocker therapy. These cases support the routine assessment of anti-AT1 R antibodies in kidney transplant recipients to identify subjects at risk. Further studies will need to determine optimal assessment protocol and the effectiveness of pre-emptive treatment with angiotensin receptor blockers. © 2015 Asian Pacific Society of Nephrology.

Association analysis of anti-Epstein-Barr nuclear antigen-1 antibodies, anti-cyclic citrullinated peptide antibodies, the shared epitope and smoking status in Brazilian patients with rheumatoid arthritis

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Michel Alexandre Yazbek

2011-01-01

Full Text Available INTRODUCTION: Epstein-Barr virus exposure appears to be an environmental trigger for rheumatoid arthritis that interacts with other risk factors. Relationships among anti-cyclic citrullinated peptide antibodies, the shared epitope, and smoking status have been observed in patients with rheumatoid arthritis from different populations. OBJECTIVE: To perform an association analysis of anti-Epstein-Barr nuclear antigen-1 antibodies, anti-cyclic citrullinated peptide antibodies, the shared epitope, and smoking status in Brazilian patients with rheumatoid arthritis. METHODS: In a case-control study, 140 rheumatoid arthritis patients and 143 healthy volunteers who were matched for age, sex, and ethnicity were recruited. Anti-Epstein-Barr nuclear antigen-1 antibodies and anti-cyclic citrullinated peptide antibodies were examined using an enzyme-linked immunosorbent assay, and shared epitope alleles were identified by genotyping. Smoking information was collected from all subjects. A comparative analysis of anti-Epstein-Barr nuclear antigen-1 antibodies, anti-cyclic citrullinated peptide antibodies, the shared epitope, and smoking status was performed in the patient group. Logistic regression analysis models were used to analyze the risk of rheumatoid arthritis. RESULTS: Anti-Epstein-Barr nuclear antigen-1 antibodies were not associated with anti-cyclic citrullinated peptide antibodies, shared epitope alleles, or smoking status. Anti-cyclic citrullinated peptide antibody positivity was significantly higher in smoking patients with shared epitope alleles (OR = 3.82. In a multivariate logistic regression analysis using stepwise selection, only anti-cyclic citrullinated peptide antibodies were found to be independently associated with rheumatoid arthritis (OR = 247.9. CONCLUSION: Anti-Epstein-Barr nuclear antigen-1 antibodies did not increase the risk of rheumatoid arthritis and were not associated with the rheumatoid arthritis risk factors studied. Smoking

TriFabs—Trivalent IgG-Shaped Bispecific Antibody Derivatives: Design, Generation, Characterization and Application for Targeted Payload Delivery

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Klaus Mayer

2015-11-01

Full Text Available TriFabs are IgG-shaped bispecific antibodies (bsAbs composed of two regular Fab arms fused via flexible linker peptides to one asymmetric third Fab-sized binding module. This third module replaces the IgG Fc region and is composed of the variable region of the heavy chain (VH fused to CH3 with “knob”-mutations, and the variable region of the light chain (VL fused to CH3 with matching “holes”. The hinge region does not contain disulfides to facilitate antigen access to the third binding site. To compensate for the loss of hinge-disulfides between heavy chains, CH3 knob-hole heterodimers are linked by S354C-Y349C disulphides, and VH and VL of the stem region may be linked via VH44C-VL100C disulphides. TriFabs which bind one antigen bivalent in the same manner as IgGs and the second antigen monovalent “in between” these Fabs can be applied to simultaneously engage two antigens, or for targeted delivery of small and large (fluorescent or cytotoxic payloads.

Increased levels of anti-glycan antibodies in patients with cystic fibrosis

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Hirche TO

2011-09-01

Full Text Available Abstract Background The prevalence of Crohn's disease (CD is increased in patients with cystic fibrosis (CF. Anti-Saccharomyces cerevisiae antibodies (ASCA have been suggested as a screening tool to detect CD in CF. Recently, several new anti-glycan antibodies have been reported in CD. Materials and methods The sera of 119 CF patients of various age groups were prospectively screened for ASCA type IgG (gASCA, anti-laminaribioside carbohydrate IgG antibodies (ALCA, anti-chitobioside carbohydrate IgA antibodies (ACCA, and anti-mannobioside carbohydrate IgG antibodies (AMCA. The frequency of these anti-glycan antibodies was then compared in patients with CD, ulcerative colitis, rheumatoid arthritis and healthy volunteers. Results A significant number of CF patients were positive for gASCA (51.3% [41.6-60.6] and up to three other anti-glycan antibodies concurrently. Serum levels of anti-glycan antibodies in CF and CD were not related to parameters of inflammation. Despite the well-documented difference in clinical course between male and female CF patients no gender difference of anti-glycan antibodies was found. In contrast, there was a significant positive correlation between anti-glycan markers and age in CF patients. Conclusions Our findings demonstrate for the first time the increased frequency of a panel of anti-glycan antibodies in CF and provide a link between the presence of these serological biomarkers and patient's age. Anti-glycan antibody profiling may therefore become a valuable tool in the care of patients with CF.

Seroprevalences of anti-Sarcocystis neurona and anti-Neospora hughesi antibodies among healthy equids in the United States.

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James, Kaitlyn E; Smith, Woutrina A; Conrad, Patricia A; Packham, Andrea E; Guerrero, Leopoldo; Ng, Mitchell; Pusterla, Nicola

2017-06-01

OBJECTIVE To describe the general seroprevalence of anti-Sarcocystis neurona and anti-Neospora hughesi antibodies among healthy equids by use of indirect fluorescent antibody tests and determine potential risk factors for seropositivity. DESIGN Cross-sectional study. SAMPLE Whole blood samples collected from 5,250 equids (1 sample/animal) across 18 states in the United States during October 2013. PROCEDURES Information regarding potential risk factors (geographic region, breed, primary use, sex, and age) was collected along with the blood samples. For each equid, an indirect fluorescent antibody test was used to determine serum titers of antibody against each of the 2 protozoal parasites. Mixed-effects logistic regression models were created to determine ORs for seropositivity. RESULTS The overall seroprevalence of anti-S neurona and anti-N hughesi antibodies in the tested equids was 78% and 34%, respectively. Of the equids, 31% were seropositive and 18% were seronegative for antibodies against both parasites. Factors associated with equids being seropositive for anti-S neurona antibodies were residence in the South, warmblood breed, and age > 5 years. Seroprevalence of anti-N hughesi antibodies did not differ among equids in different states across the country, but warmblood breed and age > 5 years were associated with seropositivity. CONCLUSIONS AND CLINICAL RELEVANCE With regard to risk factors for S neurona and N hughesi exposure and antibody response among tested equids, older age was not unexpected; however, the influences of warmblood breed and geographic location on seropositivity for anti-S neurona antibody but not for anti-N hughesi antibody deserve further investigation.

Natural Killer (NK- and T-Cell Engaging Antibody-Derived Therapeutics

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Christoph Stein

2012-06-01

Full Text Available Unmodified antibodies (abs have been successful in the treatment of hematologic malignancies, but less so for the treatment of solid tumors. They trigger anti-tumor effects through their Fc-domains, and one way to improve their efficacy is to optimize their interaction with the effectors through Fc-engineering. Another way to empower abs is the design of bispecific abs and related fusion proteins allowing a narrower choice of effector cells. Here we review frequently chosen classes of effector cells, as well as common trigger molecules. Natural Killer (NK- and T-cells are the most investigated populations in therapeutical approaches with bispecific agents until now. Catumaxomab, the first bispecific ab to receive drug approval, targets the tumor antigen Epithelial Cell Adhesion Molecule (EpCAM and recruits T-cells via a binding site for the cell surface protein CD3. The next generation of recombinant ab-derivatives replaces the broadly reactive Fc-domain by a binding domain for a single selected trigger. Blinatumomab is the first clinically successful member of this class, targeting cancer cells via CD19 and engaging T-cells by CD3. Other investigators have developed related recombinant fusion proteins to recruit effectors, such as NK-cells and macrophages. The first such agents currently in preclinical and clinical development will be discussed.

Anti-troponin I antibodies in renal transplant patients.

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Nunes, José Pedro L; Sampaio, Susana; Cerqueira, Ana; Kaya, Ziya; Oliveira, Nuno Pardal

2015-02-01

To characterize the prevalence and clinical correlates of anti-troponin I antibodies in renal transplant patients. A group of 48 consecutive renal transplant patients under immunosuppressive therapy were studied. Anti-troponin I antibodies were measured and clinical data were retrieved. An anti-troponin I antibody titer renal transplant patients, and are not associated with the presence of clinical heart disease, but are associated with lack of statin therapy. Copyright © 2014 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

Heterogeneity of Polyneuropathy Associated with Anti-MAG Antibodies

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Laurent Magy

2015-01-01

Full Text Available Polyneuropathy associated with IgM monoclonal gammopathy and anti-myelin associated glycoprotein (MAG antibodies is an immune-mediated demyelinating neuropathy. The pathophysiology of this condition is likely to involve anti-MAG antibody deposition on myelin sheaths of the peripheral nerves and it is supposed to be distinct from chronic inflammatory demyelinating neuropathy (CIDP, another immune-mediated demyelinating peripheral neuropathy. In this series, we have retrospectively reviewed clinical and laboratory findings from 60 patients with polyneuropathy, IgM gammopathy, and anti-MAG antibodies. We found that the clinical picture in these patients is highly variable suggesting a direct link between the monoclonal gammopathy and the neuropathy. Conversely, one-third of patients had a CIDP-like phenotype on electrodiagnostic testing and this was correlated with a low titer of anti-MAG antibodies and the absence of widening of myelin lamellae. Our data suggest that polyneuropathy associated with anti-MAG antibodies is less homogeneous than previously said and that the pathophysiology of the condition is likely to be heterogeneous as well with the self-antigen being MAG in most of the patients but possibly being another component of myelin in the others.

Targeted siRNA Delivery and mRNA Knockdown Mediated by Bispecific Digoxigenin-binding Antibodies

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Britta Schneider

2012-01-01

Full Text Available Bispecific antibodies (bsAbs that bind to cell surface antigens and to digoxigenin (Dig were used for targeted small interfering RNA (siRNA delivery. They are derivatives of immunoglobulins G (IgGs that bind tumor antigens, such as Her2, IGF1-R, CD22, and LeY, with stabilized Dig-binding variable domains fused to the C-terminal ends of the heavy chains. siRNA that was digoxigeninylated at its 3′end was bound in a 2:1 ratio to the bsAbs. These bsAb–siRNA complexes delivered siRNAs specifically to cells that express the corresponding antigen as demonstrated by flow cytometry and confocal microscopy. The complexes internalized into endosomes and Dig-siRNAs separated from bsAbs, but Dig-siRNA was not released into the cytoplasm; bsAb-targeting alone was thus not sufficient for effective mRNA knockdown. This limitation was overcome by formulating the Dig-siRNA into nanoparticles consisting of dynamic polyconjugates (DPCs or into lipid-based nanoparticles (LNPs. The resulting complexes enabled bsAb-targeted siRNA-specific messenger RNA (mRNA knockdown with IC50 siRNA values in the low nanomolar range for a variety of bsAbs, siRNAs, and target cells. Furthermore, pilot studies in mice bearing tumor xenografts indicated mRNA knockdown in endothelial cells following systemic co-administration of bsAbs and siRNA formulated in LNPs that were targeted to the tumor vasculature.

Binding-site analysis of opioid receptors using monoclonal anti-idiotypic antibodies

International Nuclear Information System (INIS)

Conroy, W.G.

1988-01-01

Structural relatedness between the variable region of anti-ligand antibodies and opioid binding sites allowed the generation of anti-idiotypic antibodies which recognized opioid receptors. The IgG 3 k antibodies which bound to opioid receptors were obtained when an anti-morphine antiserum was the idiotype. Both antibodies bound to opioid receptors, but only one of these blocked the binding of [ 3 H]naloxone. The antibody which did not inhibit the binding of [ 3 H]naloxone was itself displaced from the receptor by opioid ligands. The unique binding properties displayed by this antibody indicated that anti-idiotypic antibodies are not always a perfect image of the original ligand, and therefore may be more useful than typical ligands as probes for the receptor. An auto-anti-idiotypic technique was successfully used to obtain anti-opioid receptor antibodies. Another IgG 3 k antibody that blocked the binding of [ 3 H]naloxone to rat brain opioid receptors was obtained when a mouse was immunized with naloxone conjugated to bovine serum albumin. These data confirmed that an idiotype-anti-idiotype network which can generate an anti-receptor antibody normally functions when an opioid ligand is introduced into an animal in an immunogenic form

Correlation of pharmacodynamic activity, pharmacokinetics, and anti-product antibody responses to anti-IL-21R antibody therapeutics following IV administration to cynomolgus monkeys

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Spaulding Vikki

2010-04-01

Full Text Available Abstract Background Anti-IL-21R antibodies are potential therapeutics for the treatment of autoimmune diseases. This study evaluated correlations between the pharmacodynamic (PD activity, pharmacokinetics, and anti-product antibody responses of human anti-IL-21R antibodies Ab-01 and Ab-02 following IV administration to cynomolgus monkeys. Methods The PD assay was based on the ability of recombinant human IL-21 (rhuIL-21 to induce expression of the IL-2RA gene in cynomolgus monkey whole blood samples ex vivo. Monkeys screened for responsiveness to rhuIL-21 stimulation using the PD assay, were given a single 10 mg/kg IV dosage of Ab-01, Ab-02, or a control antibody (3/group, and blood samples were evaluated for PD activity (inhibition of IL-2RA expression for up to 148 days. Anti-IL-21R antibody concentrations and anti-product antibody responses were measured in serum using immunoassays and flow cytometry. Results Following IV administration of Ab-01 and Ab-02 to cynomolgus monkeys, PD activity was observed as early as 5 minutes (first time point sampled. This PD activity had good correlation with the serum concentrations and anti-product antibody responses throughout the study. The mean terminal half-life (t1/2 was ~10.6 and 2.3 days for Ab-01 and Ab-02, respectively. PD activity was lost at ~5-13 weeks for Ab-01 and at ~2 weeks for Ab-02, when serum concentrations were relatively low. The estimated minimum concentrations needed to maintain PD activity were ~4-6 nM for Ab-01 and ~2.5 nM for Ab-02, and were consistent with the respective KD values for binding to human IL-21R. For Ab-01, there was noticeable inter-animal variability in t1/2 values (~6-14 days and the resulting PD profiles, which correlated with the onset of anti-product antibody formation. While all three Ab-01-dosed animals were positive for anti-Ab-01 antibodies, only one monkey (with the shortest t1/2 and the earliest loss of PD activity had evidence of neutralizing anti-Ab-01

Experimental Study on Anti-body effects of Anti-BV on the Bee Venom Herbal Acupuncture

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Ki Rok Kwon

2005-02-01

Full Text Available Objectives : To observe physiological anti-body effects of anti-BV, acute toxic response, measurement of LD50, and the effects of anti-body were evaluated. Methods : LD50 of Anti-Bee Venom were measured, and to analyze acute toxic responses, weight, and the anti-body effects various concentrations of Anti-BV were diluted and the survival rate was measured. Cell blood count (CBC, liver, spleen, and kidney pathologies were observed from the histological aspects. Results : Experiment was conducted to observe Anti-BV as the anti-body to the bee venom and the following results were obtained: 1. Anti-BV was injected intraperitoneally and no toxic responses were witnessed. All of the experiment subjects stayed alive during the experiment, making LD50 analysis impossible. 2. Anti-BV was injected intraperitoneally in mice and no significant weight changes were measured between the control group and the experiment groups. 3. Measuring the concentration dependent survival rate, the highest survival rate was at the concentration of 1.25×102mg/kg(1/2.000 for Anti-BV. 4. No particular results were shown in the CBC test. 5. Observation of changes in the organ tissues, Anti-BV was found to suppress blood stasis in the liver and inhibit necrosis of the cells. Conclusion : Above results suggest that Anti-BV doesn't cause any toxic responses in the body and works as an anti-body to the bee venom. Further studies must be followed to secure the findings.

Association of Anti-glycan Antibodies and Inflammatory Bowel Disease Course.

Science.gov (United States)

Paul, S; Boschetti, G; Rinaudo-Gaujous, M; Moreau, A; Del Tedesco, E; Bonneau, J; Presles, E; Mounsef, F; Clavel, L; Genin, C; Flourié, B; Phelip, J-M; Nancey, S; Roblin, X

2015-06-01

The usefulness of anti-glycan antibodies alone or combined with anti-Saccharomyces cerevisiae [ASCA] or perinuclear antineutrophil cytoplasmic [pANCA] antibodies for diagnosis of inflammatory bowel disease [IBD], differentiation between Crohn's disease [CD] and ulcerative colitis [UC], disease stratification including IBD phenotype, and also for determination of the course of the disease, remain unclear. A large panel of serological anti-glycan carbohydrate antibodies, including anti-mannobioside IgG antibodies [AMCA], anti-chitobioside IgA [ACCA], anti-laminaribioside IgG antibodies [ALCA], anti-laminarin [anti-L] and anti-chitine [anti-C] were measured in the serum from a cohort of 195 patients with IBD] [107 CD and 88 UC]. The respective accuracy of isolated or combined markers for diagnosis, disease differentiation, stratification disease phenotype, and severity of the disease course, defined by a wide panel of criteria obtained from the past medical history, was assessed. The positivity of at least one anti-glycan antibody was detected in a significant higher proportion of CD and UC compared with healthy controls [p ACCA [> 51U/ml] and anti-laminarin [> 31U/ml] were significantly linked with a higher association with steroid dependency (odds ratio [OR] =2.0 [1.0-4.0], p = 0.03 and OR = 2.4 [1.1-5.2], p = 0.02, respectively]. We further defined the respective performance of anti-glycan antibodies to discriminate between patients with severe or not severe CD and UC course and determined the associated optimal cut-off values: severe CD course was significantly more likely in case of AMCA > 77U/ml [OR = 4.3; p = 0.002], ASCA > 63U/ml [OR = 3.5; p ACCA > 50U/ml [OR = 2.8; p 52U/ml [OR = 3.4; p = 0.04] and ACCA > 25U/ml [OR = 3.0; p < 0.04]. Anti-glycan antibodies are valuable serological markers, especially AMCA antibodies that may help clinicians to promptly classify patients into high risk for severe disease. Copyright © 2015 European Crohn’s and Colitis

Induction and characterization of monoclonal anti-idiotypic antibodies reactive with idiotopes of canine parvovirus neutralizing monoclonal antibodies.

NARCIS (Netherlands)

G.F. Rimmelzwaan (Guus); J. van Es (Johan); G.A. Drost; F.G.C.M. Uytdehaag (Fons); A.D.M.E. Osterhaus (Albert)

1991-01-01

textabstractMonoclonal anti-idiotypic (anti-Id) antibodies (Ab2) were generated against idiotypes (Id) of canine parvovirus (CPV) specific monoclonal antibodies (MoAbs). The binding of most of these anti-Id antibodies to their corresponding Id could be inhibited by antigen, thus classifying these

Identification of CEA-interacting proteins in colon cancer cells and their changes in expression after irradiation

Energy Technology Data Exchange (ETDEWEB)

Yoo, Byong Chul [Colorectal Cancer Branch, Research Institute, National Cancer Center, Goyang (Korea, Republic of); Yeo, Seung Gu [Dept. of Radiation Oncology, Soonchunhyang University College of Medicine, Soonchunhyang University Hospital, Cheonan (Korea, Republic of)

2017-09-15

The serum carcinoembryonic antigen (CEA) level has been recognized as a prognostic factor in colorectal cancer, and associated with response of rectal cancer to radiotherapy. This study aimed to identify CEA-interacting proteins in colon cancer cells and observe post-irradiation changes in their expression. CEA expression in colon cancer cells was examined by Western blot analysis. Using an anti-CEA antibody or IgG as a negative control, immunoprecipitation was performed in colon cancer cell lysates. CEA and IgG immunoprecipitates were used for liquid chromatography–tandem mass spectrometry (LC-MS/MS) analysis. Proteins identified in the CEA immunoprecipitates but not in the IgG immunoprecipitates were selected as CEA-interacting proteins. After radiation treatment, changes in expression of CEA-interacting proteins were monitored by Western blot analysis. CEA expression was higher in SNU-81 cells compared with LoVo cells. The membrane localization of CEA limited the immunoprecipitation results and thus the number of CEA-interacting proteins identified. Only the Ras-related protein Rab-6B and lysozyme C were identified as CEA-interacting proteins in LoVo and SNU-81 cells, respectively. Lysozyme C was detected only in SNU-81, and CEA expression was differently regulated in two cell lines; it was down-regulated in LoVo but up-regulated in SNU-81 in radiation dosage-dependent manner. CEA-mediated radiation response appears to vary, depending on the characteristics of individual cancer cells. The lysozyme C and Rab subfamily proteins may play a role in the link between CEA and tumor response to radiation, although further studies are needed to clarify functional roles of the identified proteins.

Identification of CEA-interacting proteins in colon cancer cells and their changes in expression after irradiation

International Nuclear Information System (INIS)

Yoo, Byong Chul; Yeo, Seung Gu

2017-01-01

The serum carcinoembryonic antigen (CEA) level has been recognized as a prognostic factor in colorectal cancer, and associated with response of rectal cancer to radiotherapy. This study aimed to identify CEA-interacting proteins in colon cancer cells and observe post-irradiation changes in their expression. CEA expression in colon cancer cells was examined by Western blot analysis. Using an anti-CEA antibody or IgG as a negative control, immunoprecipitation was performed in colon cancer cell lysates. CEA and IgG immunoprecipitates were used for liquid chromatography–tandem mass spectrometry (LC-MS/MS) analysis. Proteins identified in the CEA immunoprecipitates but not in the IgG immunoprecipitates were selected as CEA-interacting proteins. After radiation treatment, changes in expression of CEA-interacting proteins were monitored by Western blot analysis. CEA expression was higher in SNU-81 cells compared with LoVo cells. The membrane localization of CEA limited the immunoprecipitation results and thus the number of CEA-interacting proteins identified. Only the Ras-related protein Rab-6B and lysozyme C were identified as CEA-interacting proteins in LoVo and SNU-81 cells, respectively. Lysozyme C was detected only in SNU-81, and CEA expression was differently regulated in two cell lines; it was down-regulated in LoVo but up-regulated in SNU-81 in radiation dosage-dependent manner. CEA-mediated radiation response appears to vary, depending on the characteristics of individual cancer cells. The lysozyme C and Rab subfamily proteins may play a role in the link between CEA and tumor response to radiation, although further studies are needed to clarify functional roles of the identified proteins

Increased Anti-Phospholipid Antibodies in Autism Spectrum Disorders

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Milo Careaga

2013-01-01

Full Text Available Autism spectrum disorders (ASD are characterized by impairments in communication, social interactions, and repetitive behaviors. While the etiology of ASD is complex and likely involves the interplay of genetic and environmental factors, growing evidence suggests that immune dysfunction and the presence of autoimmune responses including autoantibodies may play a role in ASD. Anti-phospholipid antibodies are believed to occur from both genetic and environmental factors and have been linked to a number of neuropsychiatric symptoms such as cognitive impairments, anxiety, and repetitive behaviors. In the current study, we investigated whether there were elevated levels of anti-phospholipid antibodies in a cross-sectional analysis of plasma of young children with ASD compared to age-matched typically developing (TD controls and children with developmental delays (DD other than ASD. We found that levels of anti-cardiolipin, β2-glycoprotein 1, and anti-phosphoserine antibodies were elevated in children with ASD compared with age-matched TD and DD controls. Further, the increase in antibody levels was associated with more impaired behaviors reported by parents. This study provides the first evidence for elevated production of anti-phospholipid antibodies in young children with ASD and provides a unique avenue for future research into determining possible pathogenic mechanisms that may underlie some cases of ASD.

Identification of anti-HPA-1a allo-antibodies using IgG platelet antibody detection and crossmatch system assay with Galileo Echo.

Science.gov (United States)

Di Cristofaro, Julie; Frassati, Coralie; Montagnie, Rolande; Basire, Agnes; Merieux, Yves; Picard, Christophe

2015-01-01

Fetal/neonatal allo-immune thrombocytopenia is the most frequent and the most dangerous clinical condition involving anti-human platelet antigens (HPA)-1a allo-antibodies. Anti-HPA-1a allo-immunization requires rapid and accurate diagnosis to determine appropriate treatment. The Capture-P Ready-Screen assay (C-PRS) is a new qualitative immunoassay to detect IgG anti-human leukocyte antigen (HLA) and anti-HPA allo-antibodies. The aim of this study is to assess the identification of anti-HPA-1a allo-antibodies using the C-PRS assay, associated with HLA class I stripping reagents, on the automated benchtop analyzer Galileo Echo. Forty-nine sera were analyzed: without anti-HLA class I or anti-HPA allo-antibodies, with anti-HLA class I allo-antibodies, with anti-HPA-1a allo-antibodies, among which with anti-HLA class I allo-antibodies. None of the samples without allo-antibodies were reactive. Only anti-HLA antibodies, detected by cytotoxicity-dependent complement and not by Luminex, remained positive before and after stripping reagents. Of the 13 samples, anti-HPA-1a allo-antibodies that were correctly identified before and after incubation with HLA assassin reagent were 70% and 85%, respectively. Anti-glycoprotein auto-antibodies and anti-HLA allo-antibodies do not interfere with the detection of anti-HPA-1a antibodies. This preliminary study indicates that further improvement of the test will be helpful in developing a clinically useful assay in the future.

Anti-cyclic citrullinated peptide antibodies in rheumatoid arthritis patients

International Nuclear Information System (INIS)

Fakhr, A.; Ahmed, M.; Bashir, M.; Hakim, F.; Basri, R.

2017-01-01

Objective: To detect the anti cyclic citrullinated peptide (Anti-CCP) antibody in rheumatoid arthritis (RA) patients to determine its diagnostic value in Pakistani patients. Study Design: Cross sectional study. Place and Duration of Study: Military Hospital (MH) Rawalpindi, from January 2013 to June 2015. Material and Methods: A total of 58 patients with complications of rheumatoid arthritis were recruited in the study using convenient sampling technique after their informed consent. Age and gender of the patients were recorded. Blood was collected from the patients subjected to ELISA based detection of anti-CCP and latex agglutination test for detection of Rheumatoid Factor (RF). Data obtained were analyzed using Microsoft excel 2010. Results: Among the fifty eight RA patients, 40 percent were males and 60 percent were females. Age ranged between 12 to 80 years (mean age 49.74 +- 16.81 years) of the males RA patients and was higher as compared to females (mean age 43.2 +-16.70 years). ELISA based detection of anti-CCP antibody showed that about 91 percent of RA patients were positive for anti CCP antibody. About 72 percent were positive for anti CCP antibody alone, 19 percent were positive for both anti-CCP and RF and 9 percent were positive for RF. Conclusion: The results concluded that a higher percentage of the RA patients are positive for anti-CCP antibody marking its importance as a diagnostic marker. Anti-CCP has more sensitivity as compared to RF in RA patients. (author)

Co-delivery of antigen and IL-12 by Venezuelan equine encephalitis virus replicon particles enhances antigen-specific immune responses and anti-tumor effects

Science.gov (United States)

Osada, Takuya; Berglund, Peter; Morse, Michael A.; Hubby, Bolyn; Lewis, Whitney; Niedzwiecki, Donna; Hobeika, Amy; Burnett, Bruce; Devi, Gayathri R.; Clay, Timothy M.; Smith, Jonathan; Lyerly, H. Kim

2013-01-01

We recently demonstrated that Venezuelan equine encephalitis (VEE) virus-based replicon particles (VRP) encoding tumor antigens could break tolerance in the immunomodulatory environment of advanced cancer. We hypothesized that local injection of VRP expressing Interleukin-12 (IL-12) at the site of injections of VRP-based cancer vaccines would enhance the tumor-antigen-specific T cell and antibody responses and anti-tumor efficacy. Mice were immunized with VRP encoding the human tumor-associated antigen, carcinoembryonic antigen (CEA) (VRP-CEA(6D)) and VRP-IL-12 was also administered at the same site or at a distant location. CEA-specific T cell and antibody responses were measured. To determine antitumor activity, mice were implanted with MC38-CEA-2 cells and immunized with VRP-CEA with and without VRP-IL-12 and tumor growth and mouse survival were measured. VRP-IL-12 greatly enhanced CEA-specific T cell and antibody responses when combined with VRP-CEA(6D) vaccination. VRP IL-12 was superior to IL-12 protein at enhancing immune responses. Vaccination with VRP-CEA(6D) plus VRP-IL-12 was superior to VRP-CEA(6D) or VRP-IL-12 alone in inducing anti-tumor activity and prolonging survival in tumor-bearing mice. Importantly, local injection of VRP-IL-12 at the VRP-CEA(6D) injection site provided more potent activation of CEA-specific immune responses than VRP-IL-12 injected at a distant site from the VRP-CEA injections. Together, this study shows that VRP-IL-12 enhances vaccination with VRP-CEA(6D) and was more effective at activating CEA-specific T cell responses when locally expressed at the vaccine site. Clinical trials evaluating the adjuvant effect of VRP-IL-12 at enhancing the immunogenicity of cancer vaccines are warranted. PMID:22488274

Immunogenicity of anti-tumor necrosis factor antibodies-toward improved methods of anti-antibody measurement.

Science.gov (United States)

Aarden, Lucien; Ruuls, Sigrid R; Wolbink, Gertjan

2008-08-01

To date, millions of people have been treated with therapeutic monoclonal antibodies (TmAbs) for various indications. It is becoming increasingly clear that TmAbs can be immunogenic, which may reduce efficacy or induce adverse effects. Over the years, the importance of antibody formation has been questioned and sometimes minimized, as few antibody responses to TmAbs (HACA or HAHA) were reported. However, the methods to detect and quantify such antibodies used in the past have been problematic. Only recently, methods have been developed that have adequate sensitivity and are not seriously disturbed by false-positive reactions caused by rheumatoid factors, natural antibodies to Fab or F(ab')2 fragments, or Fc interactions of IgG4. The large number of treated patients, in combination with these new assays, presents a unique opportunity to study the anti-antibody immune response in man, possibly allowing us to manipulate immunogenicity in the future.

Anti-S100A4 antibody suppresses metastasis formation by blocking stroma cell invasion

DEFF Research Database (Denmark)

Klingelhöfer, Jörg; Grum-Schwensen, Birgitte; Beck, Mette K

2012-01-01

microenvironment, making it an attractive target for anti-cancer therapy. In this study, we produced a function-blocking anti-S100A4 monoclonal antibody with metastasis-suppressing activity. Antibody treatment significantly reduced metastatic burden in the lungs of experimental animals by blocking the recruitment...... of T cells to the site of the primary tumor. In vitro studies demonstrated that this antibody efficiently reduced the invasion of T cells in a fibroblast monolayer. Moreover, it was capable of suppressing the invasive growth of human and mouse fibroblasts. We presume therefore that the antibody exerts...... its activity by suppressing stroma cell recruitment to the site of the growing tumor. Our epitope mapping studies suggested that the antibody recognition site overlaps with the target binding interface of human S100A4. We conclude here that this antibody could serve as a solid basis for development...

Autoimmune encephalitis with anti-leucine-rich glioma-inactivated 1 or anti-contactin-associated protein-like 2 antibodies (formerly called voltage-gated potassium channel-complex antibodies).

Science.gov (United States)

Bastiaansen, Anna E M; van Sonderen, Agnes; Titulaer, Maarten J

2017-06-01

Twenty years since the discovery of voltage-gated potassium channel (VGKC)-related autoimmunity; it is currently known that the antibodies are not directed at the VGKC itself but to two closely associated proteins, anti-leucine-rich glioma-inactivated 1 (LGI1) and contactin-associated protein-like 2 (Caspr2). Antibodies to LGI1 and Caspr2 give well-described clinical phenotypes. Anti-LGI1 encephalitis patients mostly have limbic symptoms, and anti-Caspr2 patients have variable syndromes with both central and peripheral symptoms. A large group of patients with heterogeneous symptoms are VGKC positive but do not have antibodies against LGI1 or Caspr2. The clinical relevance of VGKC positivity in these 'double-negative' patients is questionable. This review focusses on these three essentially different subgroups. The clinical phenotypes of anti-LGI1 encephalitis and anti-Caspr2 encephalitis have been described in more detail including data on treatment and long-term follow-up. A specific human leukocyte antigen (HLA) association was found in nontumor anti-LGI1 encephalitis, but not clearly in those with tumors. There has been increasing interest in the VGKC patients without LGI1/Caspr2 antibodies questioning its relevance in clinical practice. Anti-LGI1 encephalitis and anti-Caspr2 encephalitis are separate clinical entities. Early recognition and treatment is necessary and rewarding. The term VGKC-complex antibodies, lumping patients with anti-LGI1, anti-Caspr2 antibodies or lacking both, should be considered obsolete.

Hashimoto thyroiditis, anti-thyroid antibodies and systemic lupus erythematosus.

Science.gov (United States)

Posselt, Rayana T; Coelho, Vinícius N; Skare, Thelma L

2018-01-01

To study the prevalence of Hashimoto thyroiditis (HT), anti-thyroid autoantibodies (anti-thyroglobulin or TgAb and thyroperoxidase or TPOAb) in systemic lupus erythematosus (SLE) patients. To analyze if associated HT, TgAb and/or TPOAb influence clinical or serological profiles, disease activity and/or its cumulative damage. Three hundred and one SLE patients and 141 controls were studied for thyroid stimulating hormone, thyroxin, TgAb and TPOAb by chemiluminescence and immunometric assays. Patients' charts were reviewed for serological and clinical profiles. Activity was measured by SLE Disease Activity Index and cumulative damage by Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index for SLE. SLE patients were divided into: (i) with HT; (ii) with anti-thyroid antibodies but without HT; and (iii) without HT and without anti-thyroid antibodies, and were then compared. Furthermore, SLE patients were compared according to the number of positive anti-thyroid antibodies. Hashimoto thyroiditis prevalence in SLE was 12.6% and 5.6% in controls (P = 0.02; odds ratio = 2.4; 95% CI = 1.09-5.2). Lupus patients with HT had less malar rash (P = 0.02) and more anti-Sm (P = 0.04). Anti-Sm was more common in those with two anti-thyroid antibodies than in those with one or negative. The presence of HT or the number of positive autoantibodies did not associate either with disease activity (P = 0.95) or with cumulative damage (P = 0.98). There is a two-fold increased risk of HT in SLE patients. Anti-Sm antibodies favor this association and also double antibody positivity. Disease activity and cumulative damage are not related to HT or with autoantibodies. © 2017 Asia Pacific League of Associations for Rheumatology and John Wiley & Sons Australia, Ltd.

Anti-idiotypic antibodies directed against anti-HBs among the patients with chronic hepatitis B.

Science.gov (United States)

Kobayashi, K; Suzuki, H; Ueno, Y; Nagatomi, R; Kanno, A; Otsuki, M; Toyota, T

1990-08-01

Anti-idiotypic antibodies (anti-Id) against anti-HBs were found in the sera of patients with chronic hepatitis type B. Anti-idiotypic antibodies were detected by an enzyme-linked immunosorbent assay using horseradish peroxidase conjugated mouse monoclonal anti-HBs. Ten of 72 HBsAg positive sera contained anti-Id (13.9%). The prevalence of anti-Id did not appear to correlate with HBeAg/anti-HBe system. However, HB virus specific DNA polymerase activity was significantly higher in anti-Id positive sera. In the sera obtained from the patients treated with predonisolone before, anti-Id positive rate was higher than that in the patients without a history of predonisolone therapy. These results suggest that anti-Id may be related to the immunoregulatory mechanism of HB virus replication.

Comparison between anti-CEA and anti-HER2 212Pb-labeled mAbs during α-RIT of small volume peritoneal carcinomatosis - Role of activity distribution on therapeutic efficacy and toxicity?

International Nuclear Information System (INIS)

Elgqvist, J.; Boudousq, V.; Bobyk, L.; Busson, M.; Lozza, C.; Navarro-Teulon, I.; Pouget, J.P.; Maquaire, P.; Torgue, J.

2015-01-01

Full text of publication follows. Objectives: we investigated the role of internalizing/non-internalizing monoclonal antibodies (mAbs) on the final outcome (efficacy/toxicity) of mice treated with alpha radioimmunotherapy (α- RIT) using 212 Pb-labeled mAbs. The relationship between distribution of radioactivity at the tissue level and biological parameters was also assessed. Methods: nude mice bearing 2-3 mm peritoneal nodules obtained by xenograft of A-431 tumor cells, expressing low and high level of HER2 and CEA receptors, respectively, were intraperitoneally (i.p.) injected with increasing activities (370-1480 kBq; 37 MBq/mg) of either 35A7 (non-internalising anti-CEA), Trastuzumab (internalizing anti-HER2) or PX (non-specific) 212 Pb-labeled mAbs. Control groups were injected with corresponding amount of unlabeled mAbs or with NaCl. Tumor growth was followed by bioluminescence and median survival (MS) of control and treated mice was determined. 212 Pb-35A7 and 212 Pb-Trastuzumab biodistribution was used to determine the cumulative uptake of radioactivity (UOR) in organs and tumors. Mean absorbed doses were calculated using the MIRD formalism. Haematological, liver and kidney toxicities were also assessed. Distribution of radioactivity at the tissue level was determined by digital micro-autoradiography and the relationship with biological markers of tissue damage was investigated using immunohistochemistry. Results: a mild and transient haematological toxicity in groups treated with the highest amount of activity was observed. MS of the groups treated either with internalizing or non-internalizing 212 Pb-labeled mAbs was significantly improved compared to those treated with non-specific 212 Pb-PX or those only given unlabeled mAbs or just NaCl. MS ranged from 42 days to 94 days using various activity levels of anti-CEA 212 Pb-35A7 while MS was not reached over the follow-up period of 130 days for mice treated with anti-HER2 212 Pb-Trastuzumab. However, UOR and

Novel anti-Sialyl-Tn monoclonal antibodies and antibody-drug conjugates demonstrate tumor specificity and anti-tumor activity.

Science.gov (United States)

Prendergast, Jillian M; Galvao da Silva, Ana Paula; Eavarone, David A; Ghaderi, Darius; Zhang, Mai; Brady, Dane; Wicks, Joan; DeSander, Julie; Behrens, Jeff; Rueda, Bo R

Targeted therapeutics that can differentiate between normal and malignant tumor cells represent the ideal standard for the development of a successful anti-cancer strategy. The Sialyl-Thomsen-nouveau antigen (STn or Sialyl-Tn, also known as CD175s) is rarely seen in normal adult tissues, but it is abundantly expressed in many types of human epithelial cancers. We have identified novel antibodies that specifically target with high affinity the STn glycan independent of its carrier protein, affording the potential to recognize a wider array of cancer-specific sialylated proteins. A panel of murine monoclonal anti-STn therapeutic antibodies were generated and their binding specificity and efficacy were characterized in vitro and in in vivo murine cancer models. A subset of these antibodies were conjugated to monomethyl auristatin E (MMAE) to generate antibody-drug conjugates (ADCs). These ADCs demonstrated in vitro efficacy in STn-expressing cell lines and significant tumor growth inhibition in STn-expressing tumor xenograft cancer models with no evidence of overt toxicity.

Anti-m antibody in solid tumors-two case reports.

Science.gov (United States)

Soni, Shiv Kumar; Goyal, Hari; Sood, S K; Setia, Rasika

2014-09-01

Anti-M antibodies are usually of IgM, appear as cold agglutinins and are clinically insignificant. We are reporting two cases of anti-M in cases of solid tumors where the anti-M caused discrepancy in blood grouping, reacted in coombs phase of crossmatching. Anti-M in first case showed dosage effect. These antibodies can be clinical significant when detected in coombs phase, making M antigen negative coombs compatible unit transfusion imperative.

Pathogenic and Epiphenomenal Anti-DNA Antibodies in SLE

Directory of Open Access Journals (Sweden)

Mirjana Pavlovic

2010-01-01

Full Text Available The discoveries of natural and the development of manufactured highly efficient catalytic antibodies (abzymes opens the door to many practical applications. One of the most fascinating is the use of such antibodies in human therapy and prevention (vaccination, of cancer, AIDS, autoimmune diseases. A special entity of naturally occurring DNA hydrolytic anti-DNA antibodies is emerging within past decades linked to autoimmune and lymphoproliferative disorders, such as systemic lupus erythematosus (SLE, multiple sclerosis (MS, Sjogren Syndrome (SS, B - Chronic lymphocytic leucosis (B-CLL, and Multiple Myeloma (MM. The origin of the antibodies is unknown. The underlying mechanisms of these activities are suggested to be penetration into the living cells and translocation in the nucleus, with recognition of the specific binding sites at particular (ss or ds DNA. There are controversies in the literature whether hydrolysis is a sequence-specific event. The interplay between anti-DNA antibodies and DNA is not yet elucidated. This molecular “twist” also suggests that anti-DNA antibodies with DNA hydrolytic capacity could be the organism's immune response to a microbial attack, with microbial DNA, or specific genes within microbial DNA sequence, as a target for neutralization. The catalytic antibody-based approach can become a key tool in selective chemotherapeutic strategies.

Quantitation of anti-tetanus and anti-diphtheria antibodies by enzymoimmunoassay: methodology and applications.

Science.gov (United States)

Virella, G; Hyman, B

1991-01-01

We have developed enzymoimmunoassays (EIA) for the quantitation of antibodies (Ab) to tetanus and diphtheria toxoids (TT, DT) using Immulon I plates coated with the appropriate toxoid. A preparation of human tetanus immunoglobulin with a known concentration of anti-TT Ab was used as calibrator of the anti-TT antibody assay. The assay of anti-DT Ab is calibrated with a pool of human sera whose anti-DT Ab concentration was determined by quantitative immunoelectrophoresis, using a horse anti-DT with known Ab concentration as calibrator. A peroxidase-conjugated anti-human IgG was used in both assays. ABTS was used as substrate, and the reaction was stopped after 1 min incubation with citric acid and the OD measured at 414 nm on a Vmax reader. The assays have been applied to a variety of clinical situations. In patients suspected of having tetanus, the quantitation of antibodies has been helpful in establishing a diagnosis. In patients with a history of hypersensitivity to tetanus toxoid, verification of the levels of anti-TT antibody may prevent unnecessary and potentially harmful immunizations. The assays have also been used for the diagnostic evaluation of the humoral immune response to TT and DT, both in pediatric patients and in immunosuppressed patients. Several non-responders have been detected, and we have recently used the assay to monitor the effects of fish oil administration on the humoral immune response.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies against linear epitopes on Goodpasture autoantigen in patients with anti-neutrophil cytoplasmic antibody-associated vasculitis.

Science.gov (United States)

Jia, Xiao-Yu; Yu, Jun-Tao; Hu, Shui-Yi; Li, Jian-Nan; Wang, Miao; Wang, Chen; Chen, Min; Cui, Zhao; Zhao, Ming-Hui

2017-09-01

In a substantial number of patients with crescentic glomerulonephritis, both anti-glomerular basement membrane (GBM) antibodies and anti-neutrophil cytoplasmic antibodies (ANCA) are detected simultaneously. ANCA is presumed to be the initial event but the mechanism is unknown. In the present study, we investigated the antibodies against linear epitopes on Goodpasture autoantigen in sera from patients with ANCA-associated vasculitis, aiming to reveal the mechanisms of the coexistence of the two kinds of autoantibodies. Thirty-one patients with ANCA-associated vasculitis were enrolled in this study. Twenty-four overlapping linear peptides were synthesized across the whole sequence of Goodpasture autoantigen. Serum antibodies against linear peptides were detected by ELISA and their associations with clinical features were further analyzed. Twenty-five out of the thirty-one (80.6%) sera from patients with ANCA-associated vasculitis possessed antibodies against linear peptides on Goodpasture autoantigen. These antibodies could be detected in 50% of patients with normal renal function (Scr ≤ 133 μmol/L), 70% of patients with moderate renal dysfunction (133 μmol/L  600 μmol/L) (P = 0.032). The highest recognition frequencies were found for peptides P4 (51.6%), P14 (54.8%), and P24 (54.8%), which contained the sequences that constitute the conformational epitopes of E A (P4) and E B (P14) recognized by anti-GBM antibodies. The level of anti-P4 antibodies was positively correlated with the percentage of crescents in glomeruli (r = 0.764, P = 0.027). Patients with anti-P24 antibodies had a significantly higher prevalence of renal dysfunction on diagnosis (88.2 vs. 42.9%, P = 0.018). Antibodies against linear epitopes on Goodpasture autoantigen could be detected in sera of patients with ANCA-associated vasculitis, which might mediate the production of antibodies towards the conformational epitopes on Goodpasture autoantigen, namely, the anti-GBM antibodies.

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

Quantification of anti-Leishmania antibodies in saliva of dogs.

Science.gov (United States)

Cantos-Barreda, Ana; Escribano, Damián; Bernal, Luis J; Cerón, José J; Martínez-Subiela, Silvia

2017-08-15

Detection of serum anti-Leishmania antibodies by quantitative or qualitative techniques has been the most used method to diagnose Canine Leishmaniosis (CanL). Nevertheless, saliva may represent an alternative to blood because it is easy to collect, painless and non-invasive in comparison with serum. In this study, two time-resolved immunofluorometric assays (TR-IFMAs) for quantification of anti-Leishmania IgG2 and IgA antibodies in saliva were developed and validated and their ability to distinguish Leishmania-seronegative from seropositive dogs was evaluated. The analytical study was performed by evaluation of assay precision, sensitivity and accuracy. In addition, serum from 48 dogs (21 Leishmania-seropositive and 27 Leishmania-seronegative) were analyzed by TR-IFMAs. The assays were precise, with an intra- and inter-assay coefficients of variation lower than 11%, and showed high level of accuracy, as determined by linearity under dilution (R 2 =0.99) and recovery tests (>88.60%). Anti-Leishmania IgG2 antibodies in saliva were significantly higher in the seropositive group compared with the seronegative (pLeishmania IgA antibodies between both groups were observed. Furthermore, TR-IFMA for quantification of anti-Leishmania IgG2 antibodies in saliva showed higher differences between seropositive and seronegative dogs than the commercial assay used in serum. In conclusion, TR-IFMAs developed may be used to quantify anti-Leishmania IgG2 and IgA antibodies in canine saliva with an adequate precision, analytical sensitivity and accuracy. Quantification of anti-Leishmania IgG2 antibodies in saliva could be potentially used to evaluate the humoral response in CanL. However, IgA in saliva seemed not to have diagnostic value for this disease. For future studies, it would be desirable to evaluate the ability of the IgG2 assay to detect dogs with subclinical disease or with low antibody titers in serum and also to study the antibodies behaviour in saliva during the

Generation of anti-idiotype scFv for pharmacokinetic measurement in lymphoma patients treated with chimera anti-CD22 antibody SM03.

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Qi Zhao

Full Text Available Pre-clinical and clinical studies of therapeutic antibodies require highly specific reagents to examine their immune responses, bio-distributions, immunogenicity, and pharmacodynamics in patients. Selective antigen-mimicking anti-idiotype antibody facilitates the assessment of therapeutic antibody in the detection, quantitation and characterization of antibody immune responses. Using mouse specific degenerate primer pairs and splenocytic RNA, we generated an idiotype antibody-immunized phage-displayed scFv library in which an anti-idiotype antibody against the therapeutic chimera anti-CD22 antibody SM03 was isolated. The anti-idiotype scFv recognized the idiotype of anti-CD22 antibody and inhibited binding of SM03 to CD22 on Raji cell surface. The anti-idiotype scFv was subsequently classified as Ab2γ type. Moreover, our results also demonstrated firstly that the anti-idiotype scFv could be used for pharmacokinetic measurement of circulating residual antibody in lymphoma patients treated with chimera anti-CD22 monoclonal antibody SM03. Of important, the present approach could be easily adopted to generate anti-idiotype antibodies for therapeutic antibodies targeting membrane proteins, saving the cost and time for producing a soluble antigen.

Effects of anti-tumor necrosis factor-alpha and anti-intercellular adhesion molecule-1 antibodies on ischemia/reperfusion lung injury.

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Chiang, Chi-Huei

2006-10-31

Inhibition of neutrophil activation and adherence to endothelium by antibodies to tumor necrosis factor-alpha (TNF-alpha) and intercellular adhesion molecules (ICAM-1), respectively, might attenuate ischemia-reperfusion injury (I/R). I/R was conducted in an isolated rat lung model. Anti-TNF-alpha antibody and/or anti-ICAM-1 antibody were added before ischemia or after reperfusion. Hemodynamic changes, lung weight gain (LWG), capillary filtration coefficients (Kfc), and pathologic changes were assessed to evaluate the severity of I/R. The LWG, Kfc, pathological changes and lung injury score of treatment groups with anti-TNF-alpha antibody treatment, either pre-ischemia or during reperfusion, were less than those observed in control groups. Similar findings were found in group treated with anti-ICAM-1 antibody or combination therapy during reperfusion. In contrast, pre-I/R treatment with anti-ICAM-1 antibody induced severe lung edema and failure to complete the experimental procedure. No additional therapeutic effect was found in combination therapy. We conclude that TNF-alpha and ICAM-1 play important roles in I/R. Anti-TNF-alpha antibody has therapeutic and preventive effects on I/R. However, combined therapy with anti-TNF-alpha antibody and anti-ICAM-1 antibody may have no additive effect and need further investigation.

Localization of radiolabeled anti-CEA antibody in subcutaneous and intrahepatic colorectal xenografts: influence of tumor size and location within host organ on antibody uptake

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Dearling, Jason L.J. [Cancer Research UK Targeting and Imaging Group, Research Department of Oncology, UCL Cancer Institute, Paul O' Gorman Building, University College London, London WC1E 6BT (United Kingdom)], E-mail: j.dearling@hotmail.com; Flynn, Aiden A.; Qureshi, Uzma [Cancer Research UK Targeting and Imaging Group, Research Department of Oncology, UCL Cancer Institute, Paul O' Gorman Building, University College London, London WC1E 6BT (United Kingdom); Whiting, Stephen [Department of Clinical Biochemistry, Royal Free and University College Medical School, UCL, Royal Free Campus, London NW3 2PF (United Kingdom); Boxer, Geoffrey M.; Green, Alan; Begent, Richard H.J.; Pedley, R. Barbara [Cancer Research UK Targeting and Imaging Group, Research Department of Oncology, UCL Cancer Institute, Paul O' Gorman Building, University College London, London WC1E 6BT (United Kingdom)

2009-11-15

Introduction: Radioimmunotherapy (RIT) has been shown to be more effective against solid tumor micrometastases, possibly due to an inverse relationship between tumor size and radiolabeled antibody uptake. In this study, the accretion of radiolabeled antibody in intrahepatic micrometastases in an experimental model was investigated using quantitative digital autoradiography, enabling the analysis of antibody uptake in microscopic tumors. Methods: Mice bearing subcutaneous or intrahepatic metastatic models of LS174T colorectal cancer were injected with radiolabeled anti-carcinoembryonic antigen antibody ([{sup 125}I]A5B7). Tissues were taken to investigate distribution of radionuclide and tumor uptake. In a therapy study, mice bearing intrahepatic metastatic tumors were injected with [{sup 131}I]A5B7. Results: Subcutaneous tumors and large metastatic deposits had similar uptake (e.g., {approx}15%ID/g at 24 h). Small metastatic deposits had higher uptake (e.g., {approx}80%ID/g at 24 h) and prolonged retention at later time points. Small deposit uptake was significantly reduced by accompanying large deposits in the same liver. RIT resulted in increased survival time (untreated mean survival of 21.6{+-}12.9 vs. treated mean survival of 39.1{+-}30.8 days), but there was a large range of response within groups, presumably due to variation in pattern and extent of tumor as observed in the biodistribution study. Liver function tests and body weight did not change with tumor growth or therapy response, strongly supporting the use of in vivo imaging in metastatic tumor therapy studies. Conclusions: Radioimmunodetection and therapy might be greatly influenced by the size and distribution of intrahepatic tumor deposits.

Localization of radiolabeled anti-CEA antibody in subcutaneous and intrahepatic colorectal xenografts: influence of tumor size and location within host organ on antibody uptake

International Nuclear Information System (INIS)

Dearling, Jason L.J.; Flynn, Aiden A.; Qureshi, Uzma; Whiting, Stephen; Boxer, Geoffrey M.; Green, Alan; Begent, Richard H.J.; Pedley, R. Barbara

2009-01-01

Introduction: Radioimmunotherapy (RIT) has been shown to be more effective against solid tumor micrometastases, possibly due to an inverse relationship between tumor size and radiolabeled antibody uptake. In this study, the accretion of radiolabeled antibody in intrahepatic micrometastases in an experimental model was investigated using quantitative digital autoradiography, enabling the analysis of antibody uptake in microscopic tumors. Methods: Mice bearing subcutaneous or intrahepatic metastatic models of LS174T colorectal cancer were injected with radiolabeled anti-carcinoembryonic antigen antibody ([ 125 I]A5B7). Tissues were taken to investigate distribution of radionuclide and tumor uptake. In a therapy study, mice bearing intrahepatic metastatic tumors were injected with [ 131 I]A5B7. Results: Subcutaneous tumors and large metastatic deposits had similar uptake (e.g., ∼15%ID/g at 24 h). Small metastatic deposits had higher uptake (e.g., ∼80%ID/g at 24 h) and prolonged retention at later time points. Small deposit uptake was significantly reduced by accompanying large deposits in the same liver. RIT resulted in increased survival time (untreated mean survival of 21.6±12.9 vs. treated mean survival of 39.1±30.8 days), but there was a large range of response within groups, presumably due to variation in pattern and extent of tumor as observed in the biodistribution study. Liver function tests and body weight did not change with tumor growth or therapy response, strongly supporting the use of in vivo imaging in metastatic tumor therapy studies. Conclusions: Radioimmunodetection and therapy might be greatly influenced by the size and distribution of intrahepatic tumor deposits.

Anti-B cell antibody therapies for inflammatory rheumatic diseases

DEFF Research Database (Denmark)

Faurschou, Mikkel; Jayne, David R W

2014-01-01

Several monoclonal antibodies targeting B cells have been tested as therapeutics for inflammatory rheumatic diseases. We review important observations from randomized clinical trials regarding the efficacy and safety of anti-B cell antibody-based therapies for rheumatoid arthritis, systemic lupus...... and functions in rheumatic disorders. Future studies should also evaluate how to maintain disease control by means of conventional and/or biologic immunosuppressants after remission-induction with anti-B cell antibodies....

Oxidized LDL-induced angiogenesis involves sphingosine 1-phosphate: prevention by anti-S1P antibody.

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Camaré, Caroline; Trayssac, Magali; Garmy-Susini, Barbara; Mucher, Elodie; Sabbadini, Roger; Salvayre, Robert; Negre-Salvayre, Anne

2015-01-01

Neovascularization occurring in atherosclerotic lesions may promote plaque expansion, intraplaque haemorrhage and rupture. Oxidized LDL (oxLDL) are atherogenic, but their angiogenic effect is controversial; both angiogenic and anti-angiogenic effects have been reported. The angiogenic mechanism of oxLDL is partly understood, but the role of the angiogenic sphingolipid, sphingosine 1-phosphate (S1P), in this process is not known. Thus, we investigated whether S1P is involved in the oxLDL-induced angiogenesis and whether an anti-S1P monoclonal antibody can prevent this effect. Angiogenesis was assessed by capillary tube formation by human microvascular endothelial cells (HMEC-1) cultured on Matrigel and in vivo by the Matrigel plug assay in C57BL/6 mice. Human oxLDL exhibited a biphasic angiogenic effect on HMEC-1; low concentrations were angiogenic, higher concentrations were cytotoxic. The angiogenic response to oxLDL was blocked by the sphingosine kinase (SPHK) inhibitor, dimethylsphingosine, by SPHK1-siRNA and by an anti-S1P monoclonal antibody. Moreover, inhibition of oxLDL uptake and subsequent redox signalling by anti-CD36 and anti-LOX-1 receptor antibodies and by N-acetylcysteine, respectively, blocked SPHK1 activation and tube formation. In vivo, in the Matrigel plug assay, low concentrations of human oxLDL or murine oxVLDL also triggered angiogenesis, which was prevented by i.p. injection of the anti-S1P antibody. These data highlight the role of S1P in angiogenesis induced by oxLDL both in HMEC-1 cultured on Matrigel and in vivo in the Matrigel plug model in mice, and demonstrate that the anti-S1P antibody effectively blocks the angiogenic effect of oxLDL. © 2014 The British Pharmacological Society.

Natural Mosquito-Pathogen Hybrid IgG4 Antibodies in Vector Borne Diseases: A Hypothesis

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Berlin L. Londono-Renteria

2016-09-01

Full Text Available Chronic exposure to antigens may favor the production of IgG4 antibodies over other antibody types. Recent studies have shown that up to a 30% of normal human IgG4 is bi-specific and is able to recognize two antigens of different nature. A requirement for this specificity is the presence of both eliciting antigens in the same time and at the same place where the immune response is induced. During transmission of most vector-borne diseases, the pathogen is delivered to the vertebrate host along with the arthropod saliva during blood feeding and previous studies have shown the existence of IgG4 antibodies against mosquito salivary allergens. However, there is very little ongoing research or information available regarding IgG4 bi-specificity with regards to infectious disease, particularly during immune responses to vector-borne diseases such as malaria, filariasis or dengue virus infection. Here, we provide background information and present our hypothesis that IgG4 may not only be a useful tool to measure exposure to infected mosquito bites, but that these bi-specific antibodies may also play an important role in modulation of the immune response against malaria and other vector-borne diseases in endemic settings.

Carbamylated albumin is one of the target antigens of anti-carbamylated protein antibodies.

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Nakabo, Shuichiro; Hashimoto, Motomu; Ito, Shinji; Furu, Moritoshi; Ito, Hiromu; Fujii, Takao; Yoshifuji, Hajime; Imura, Yoshitaka; Nakashima, Ran; Murakami, Kosaku; Kuramoto, Nobuo; Tanaka, Masao; Satoh, Junko; Ishigami, Akihito; Morita, Satoshi; Mimori, Tsuneyo; Ohmura, Koichiro

2017-07-01

Anti-carbamylated protein (anti-CarP) antibodies are detected in RA patients. Fetal calf serum is used as an antigen source in anti-CarP ELISA, and the precise target antigens have not been found. We aimed to identify the target antigens of anti-CarP antibodies. Western blotting of anti-CarP antibodies was conducted. Anti-carbamylated human albumin (CarALB) antibody was detected by in-house ELISA for 493 RA patients and 144 healthy controls (HCs). An inhibition ELISA of anti-CarP antibodies by CarALB and citrullinated albumin (citALB) was performed using eight RA patients' sera. Serum CarALB was detected by liquid chromatography-tandem mass spectroscopy (LC/MS/MS), and the serum MPO concentration was measured by ELISA. We focused on carbamylated albumin because it corresponded to the size of the thickest band detected by western blotting of anti-CarP antibodies. Anti-CarALB antibody was detected in 31.4% of RA patients, and the correlation of the titres between anti-CarALB and anti-CarP was much closer than that between anti-citALB and anti-CCP antibodies (ρ = 0.59 and ρ = 0.16, respectively). The inhibition ELISA showed that anti-CarP antibodies were inhibited by CarALB, but not by citALB. CarALB was detected in sera from RA patients by LC/MS/MS. The serum MPO concentration was correlated with disease activity and was higher in RA patients with anti-CarALB antibody than in those without. We found that carbamylated albumin is a novel target antigen of anti-CarP antibodies, and it is the first reported target antigen that has not been reported as the target of ACPA. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com

The anti-thyroid antibody and I-131 uptake in thyroid disorder patient

International Nuclear Information System (INIS)

Faridul Alam; Fatema Sultana Haque; Mohammad Abdul Karim; Liaquat Ali; Omer Faruque; Azad Khan, A.K.

2004-01-01

The problem of thyroid disorder is extensive in Bangladesh, even more than that of other developing countries. The high incidence rate of goiter is reduced after universal iodine supplement. This study has been undertaken to study the an-thyroid anti-body level among the thyroid disorder population (anti-TPO and anti-thyrogobulin antibody) and TSAb among Graves' disease and sub-acute thyroiditis. This study was performed over 300 persons of them 150 have some type of thyroid (patient) disorder and 150 have got no clinical thyroid disorder (volunteer). We also studied TSH receptor anti-body (TSAb) in 112 Graves' disease patients and 86 patients with sub-acute thyroiditis. All the patient had I-131 Uptake in 24 hours. Among the patient 42(28%) had elevated anti-TPO, 12(8%) had borderline and 96(64%) had normal anti-TPO. It was found the uptake percentage of this group of patient hade slight lower than average uptake of our population. 13±5% It was found that 28(18.6%) had elevated anti thyrogobulin anti-body, 9 (6.2%) had borderline and 113(75.3%) had normal level anti thyrogobulin anti-body. It was also that found the uptake percentage of this group of patient had slight lower than average uptake of our population. We also found that 21% patient had elevated both the antibodies. Among the normal volunteer 24(16%) had elevated anti-TPO, 8 (5.3%) had borderline and 118(78.7%) had normal level of anti-TPO. Thyroid 1-131 uptake was 15±4%. It was found that 14(9.3%) had elevated anti thyrogobulin anti-body, 6(4.1%) had borderline and 130 (76.6%) had normal level of anti thyrogobulin anti-body. Among the normal volunteer 6% had elevated both the antibodies. It was found 91% patient Graves' disease had positive TSAb and 92% of' sub-acute thyroiditis has negative TSAb, I-131 uptake was 31±8% among this group of patient.. Thyroid stimulating antibody is found in 91% of Graves' disease and very few patient with sub-acute thyroiditis. The uptake of I-131 in sub

Antibody Engineering and Therapeutics

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Almagro, Juan Carlos; Gilliland, Gary L; Breden, Felix; Scott, Jamie K; Sok, Devin; Pauthner, Matthias; Reichert, Janice M; Helguera, Gustavo; Andrabi, Raiees; Mabry, Robert; Bléry, Mathieu; Voss, James E; Laurén, Juha; Abuqayyas, Lubna; Barghorn, Stefan; Ben-Jacob, Eshel; Crowe, James E; Huston, James S; Johnston, Stephen Albert; Krauland, Eric; Lund-Johansen, Fridtjof; Marasco, Wayne A; Parren, Paul WHI; Xu, Kai Y

2014-01-01

The 24th Antibody Engineering & Therapeutics meeting brought together a broad range of participants who were updated on the latest advances in antibody research and development. Organized by IBC Life Sciences, the gathering is the annual meeting of The Antibody Society, which serves as the scientific sponsor. Preconference workshops on 3D modeling and delineation of clonal lineages were featured, and the conference included sessions on a wide variety of topics relevant to researchers, including systems biology; antibody deep sequencing and repertoires; the effects of antibody gene variation and usage on antibody response; directed evolution; knowledge-based design; antibodies in a complex environment; polyreactive antibodies and polyspecificity; the interface between antibody therapy and cellular immunity in cancer; antibodies in cardiometabolic medicine; antibody pharmacokinetics, distribution and off-target toxicity; optimizing antibody formats for immunotherapy; polyclonals, oligoclonals and bispecifics; antibody discovery platforms; and antibody-drug conjugates. PMID:24589717

Clinical prospective study with radioiodinated monoclonal antibodies directed against colorectal cancer

International Nuclear Information System (INIS)

Chatal, J.F.; Douillard, J.Y.; Kremer, M.; Curtet, C.; Le Mevel, B.; Saccavini, J.C.; Maurel, C.; Aubry, J.

1985-01-01

The diagnostic application of three monoclonal antibodies are studied: an anti-carcinoembryonic antigen (CEA) antibody designated as 202 and two monoclonal antibodies, designated as 17-1A and 19-9, which recognize different antigens associated with gastrointestinal carcinomas. The complementary specificity of these antibodies was determined by an immuno-histochemical study and the scintigraphic detection parameters by a radiopharmacokinetic study in colic-tumour-bearing nude mice. On the basis of a prospective study, the value of immunoscintigraphy was compared with conventional methods such as ultrasonography and computed tomography for localization of recurrences of colorectal cancers. (UK)

Frequency of anti thyroid peroxidase antibody in patients of vitiligo

International Nuclear Information System (INIS)

Zhokhar, A.; Shaikh, Z.I.

2013-01-01

Objective: The objective of this study was to compare the frequency of anti thyroid peroxidase antibody in patients suffering from vitiligo with healthy control group. Type of Study: Case control study. Settings: Dermatology Department, Military Hospital, Rawalpindi, from 20th March 2010 to 20th July 2011. Material and Methods: Fifty clinically diagnosed patients of vitiligo, age = 18 yrs and both genders with no history of thyroid disease, past or current use of drugs for thyroid disorder or thyroid surgery were included as cases (Group A). Fifty healthy individuals with no evidence of vitiligo or thyroid disorder on history and physical examination and with no family history of vitiligo, matched for age and gender with cases, were included as control (Group B). Serum anti thyroid peroxidase (anti TPO) antibodies were measured using enzyme linked immunosorbent assay (ELISA) in both cases and control. Results: Eight (16%) patients in Group A were anti-thyroid peroxidase antibody positive and forty two (84%) patients were negative while one (2%) patient was anti-thyroid peroxidase antibody positive in Group B and forty nine (98%) patients were negative (p = 0.001). Conclusion: Anti TPO antibody is significantly more common in patients of vitiligo as compared to general population. (author)

Two Unique Cases with Anti-GluR Antibody-Positive Encephalitis

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Kosuke Matsuzono

2013-01-01

Full Text Available We report two cases of anti-glutamic acid receptor (anti-GluR antibody-positive encephalitis in males with symptoms such as Parkinsonism, urinary retention, and paralytic ileus. Although non-herpetic encephalitis typically shows magnetic resonance imaging (MRI lesions in the limbic system during early stages, the present cases showed MRI lesions during later stages in the bilateral claustrum and pons. In both cases, anti-GluRε2 and δ2 antibodies were later shown to be positive in the cerebrospinal fluid but negative in the serum. Although early detection of anti-GluR antibodies is essential, early treatment may be significantly more important.

The significance of anti-DFS70 antibodies in the diagnosis of autoimmune disorders

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Barbara Nieradko-Iwanicka

2017-06-01

Full Text Available Background . Anti-DFS70 antibodies are a subgroup of antinuclear antibodies (ANA. They are connected with the dense fine speckled autoantigen of 70 kD, known as the lens epithelium-derived growth factor p75. Objectives. The objective of the review is to present the role of anti-DFS70 antibodies in the diagnosis of autoimmune diseases on the basis of recent publications. Material and methods . The authors searched for articles in the Pubmed database using the key words: anti-DFS70 antibodies, systemic autoimmune rheumatic diseases and autoimmune disorders. Results . Anti-DFS70 antibodies can be detected in eye diseases, atopic diseases, alopecia areata, fibromyalgia, asthma, chronic fatigue syndrome, tumors, Hashimoto’s disease, Graves’ disease, Behcet’s disease, inflammatory bowel diseases, neoplasms and in infectious diseases. These antibodies are sometimes detected in patients with ANA-associated rheumatic diseases (AARD . Up to 20% of serum samples from healthy individuals (HI are ANA-positive. This is probably due to the presence of monospecific anti-DFS70 antibodies. Monospecific anti-DFS70 antibodies are not associated with AARD , but mixed anti-DFS70 can be found in AARD . Conclusions . Family physicians usually do not order ANA, extractable nuclear antigens (ENA or anti-DFS70 antibodies, but they should be aware that anti-DFS70 antibodies are biomarkers that can discriminate AARD from non-AARD , save patients from unnecessary, potentially toxic treatment and save finances typically spent on retesting and visits to specialists.

Influence of type I IFN signaling on anti-MOG antibody-mediated demyelination

DEFF Research Database (Denmark)

Berg, Carsten Tue; Khorooshi, Reza M. H.; Asgari, Nasrin

2017-01-01

Background Antibodies with specificity for myelin oligodendrocyte glycoprotein (MOG) are implicated in multiple sclerosis and related diseases. The pathogenic importance of anti-MOG antibody in primary demyelinating pathology remains poorly characterized. Objective The objective of this study...... is to investigate whether administration of anti-MOG antibody would be sufficient for demyelination and to determine if type I interferon (IFN) signaling plays a similar role in anti-MOG antibody-mediated pathology, as has been shown for neuromyelitis optica-like pathology. Methods Purified IgG2a monoclonal anti...... demyelination in wild-type and IFNAR1-KO mice. Conclusions Anti-MOG antibody and complement was sufficient to induce callosal demyelination, and pathology was dependent on type I IFN. Induction of EAE in IFNAR1-KO mice overcame the dependence on type I IFN for anti-MOG and complement-mediated demyelination....

High affinity anti-TIM-3 and anti-KIR monoclonal antibodies cloned from healthy human individuals.

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Stefan Ryser

Full Text Available We report here the cloning of native high affinity anti-TIM-3 and anti-KIR IgG monoclonal antibodies (mAbs from peripheral blood mononuclear cells (PBMC of healthy human donors. The cells that express these mAbs are rare, present at a frequency of less than one per 105 memory B-cells. Using our proprietary multiplexed screening and cloning technology CellSpot™ we assessed the presence of memory B-cells reactive to foreign and endogenous disease-associated antigens within the same individual. When comparing the frequencies of antigen-specific memory B-cells analyzed in over 20 screening campaigns, we found a strong correlation of the presence of anti-TIM-3 memory B-cells with memory B-cells expressing mAbs against three disease-associated antigens: (i bacterial DNABII proteins that are a marker for Gram negative and Gram positive bacterial infections, (ii hemagglutinin (HA of influenza virus and (iii the extracellular domain of anaplastic lymphoma kinase (ALK. One of the native anti-KIR mAbs has similar characteristics as lirilumab, an anti-KIR mAb derived from immunization of humanized transgenic mice that is in ongoing clinical trials. It is interesting to speculate that these native anti-TIM-3 and anti-KIR antibodies may function as natural regulatory antibodies, analogous to the pharmacological use in cancer treatment of engineered antibodies against the same targets. Further characterization studies are needed to define the mechanisms through which these native antibodies may function in healthy and disease conditions.

A bispecific peptide based near-infrared probe for in vivo tumor diagnosis

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Ding, Li; Chen, Wei R.; Gu, Yueqing

2013-02-01

The epidermal growth factor receptor EGFR and HER2 are members of recepeter tyrosine kinase family. Overexpression of EGFR and HER2 has been observed in a variety of human tumors, making these receptors promising targets for tumor diagnosis. An affibody targeting HER2 and a nanobody targeting EGFR were reported before. In this Manuscript, we described an bispecific peptide combined with an affibody and a nanonbody through a linker―（G4S）3 . And the bispecific peptide was labeled with near-infrared (NIR) fluorochrome ICG-Der-02 for in vivo tumor EGFR and HER2 targeting. Afterwards, the EGFR and HER2 specificity of the fluorescent probe was tested in vitro for receptor binding assay and fluorescence microscopy and in vivo for subcutaneous MDA-MB-231 tumor targeting. The results indicated that the bispecific peptide had a high affinity to EGFR and HER2. Besides, in vitro and in vivo tumor targeting experiment indicated that the ICG-Der-02-( bispecific peptide) showed excellent tumor activity accumulation. Noninvasive NIR fluorescence imaging is able to detect tumor EGFR and HER2 expression based upon the highly potent bispecific peptide probe.

Anti-idiotypic antibodies to poliovirus antibodies in commercial immunoglubulin preparations, human serum and milk.

NARCIS (Netherlands)

M. Hahn-Zoric; B. Carlsson; S. Jeansson; H.P. Ekre; A.D.M.E. Osterhaus (Albert); D. Roberton; L.A. Hanson

1993-01-01

textabstractOur previous studies have suggested that fetal antibody production can be induced by maternal antiidiotypic antibodies transferred to the fetus via the placenta. We tested commercial Ig, sera, and milk for the presence of anti-idiotypic antibodies to poliovirus type 1, using affinity

Persistent fetal sinus bradycardia associated with maternal anti-SSA/Ro and anti-SSB/La antibodies

NARCIS (Netherlands)

Chockalingam, Priya; Jaeggi, Edgar T.; Rammeloo, Lukas A.; Haak, Monique C.; Adama van Scheltema, Phebe N.; Breur, Johannes M. P. J.; Bartelings, Margot M.; Clur, Sally-Ann B.; Blom, Nico A.

2011-01-01

To study the clinical course and outcome of fetal sinus bradycardia (SB) due to maternal antibody-induced sinus node dysfunction. We reviewed the maternal, prenatal, and postnatal findings of fetuses with SB associated with elevated maternal anti-SSA/Ro and anti-SSB/La antibodies. Of the 6 cases

Characterization of a Novel Humanized Anti-CD20 Antibody with Potent Anti-Tumor Activity against Non-Hodgkin's Lymphoma

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Haifeng Zhang

2013-09-01

Full Text Available Background: Rituximab, a mouse Fab and human Fc chimeric antibody, has been widely used to treat Non-Hodgkin's lymphoma (NHL. However, only 48% of patients respond to the treatment and complete response rate is below 10%. Also, immunogenicity was reported in 17-20% patients receiving the treatment, making it unsuitable for long term diseases such as autoimmune disorders. It has been a hot research field to “humanize” rituximab toward improved efficacy and reduced immunogenicity. Methods: In this study, an advanced antibody humanization technology was applied to the sequence of the anti-CD20 antibody 2B8, its sequence of which was based on the original murine monoclonal antibody of rituximab in Roche. The complementarity-determining regions (CDRs of the humanized antibodies were further optimized through computer-aided molecular dock. Results: Five novel humanized anti-CD20 antibodies 1-5(1635, 1534, 3637, 1634 and 1536 were generated and their immunogenicity was significantly decreased when compared to rituximab. The novel humanized anti-CD20 antibodies 1-5 retained the binding activity of their murine counterpart, as demonstrated by the fluorescence-activated cell-sorting analysis (FACS. When compared to rituximab, the humanized antibodies still have the similar properties on both complement-dependent cytotoxicity (CDC and antibody-dependent cell-mediated cytotoxicity (ADCC. Furthermore, its anti-tumor efficacy in xenograft model is comparable to that of rituximab. Conclusion: The humanized anti-CD20 antibodies 1-5 have lower immunogenicity than rituximab. And at the same time, they still retain the anti-tumor effect both in vitro and vivo.

Mammalian Cell Culture Clarification: A Case Study Using Chimeric Anti-CEA Monoclonal Antibodies

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Mohamed Ali Abol Hassan

2011-12-01

Full Text Available The extracellular expression of monoclonal antibodies (mAbs in mammalian cell culture provides both opportunities and restrictions for the design of robust harvest and clarification operations. With advances in cell culture media and cell lines, it is now possible to achieve high titers of over 5 g/l for mAbs. However, Mammalian cells are sensitive to breakage due to shear stress that can result in release of proteases and other host cell proteins (HCPs which eventually affects product stability and purity. There is larger number of mAbs undergoing clinical development and it has placed significant importance on platform technologies of process development. Generally, Centrifugation and microfiltration are the primary harvest techniques used in the industry and depth filtration is also used as a step operation on clarification. This study compares the unit operations; centrifugation, microfiltration and depth filtration for maximum recovery of monoclonal antibodies. The results have shown that the depth filtration as more suitable operation for mammalian cell culture clarification since it gives 96% recovery of mAbs in comparison to centrifugation and microfiltration. ABSTRAK: Pengungkapan luar sel dari antibodi monoklon (monoclonal antibodies ((mAbs dalam kultur sel mamalia memberi ruang dan batasan terhadap reka bentuk penuaian yang cekap dan penerangan operasi. Dengan kemajuan dalam media sel kultur dan cell lines (produk yang berupa sel kekal yang digunakan untuk tujuan kajian biologi, kini adalah berkemungkinan untuk memperolehi titer tinggi melebihi 5g/l untuk mAbs [2]. Walaupun begitu, sel mamalia sensitif terhadap retakan disebabkan tegasan ricih yang menyebabkan pengeluaran protease dan hos sel protein yang lain, (host cell proteins (HCPs akhirnya mempengaruhi kestabilan dan keaslian produk. Terdapat mAbs dalam jumlah besar yang masih menjalani pembangunan klinikal dan sesungguhnya ini penting sebagai satu landasan teknologi dalam

Long-term outcome of anti-glomerular basement membrane antibody disease treated with immunoadsorption.

Science.gov (United States)

Biesenbach, Peter; Kain, Renate; Derfler, Kurt; Perkmann, Thomas; Soleiman, Afschin; Benharkou, Alexandra; Druml, Wilfred; Rees, Andrew; Säemann, Marcus D

2014-01-01

Anti-glomerular basement membrane (GBM) antibody disease may lead to acute crescentic glomerulonephritis with poor renal prognosis. Current therapy favours plasma exchange (PE) for removal of pathogenic antibodies. Immunoadsorption (IAS) is superior to PE regarding efficiency of antibody-removal and safety. Apart from anecdotal data, there is no systemic analysis of the long-term effects of IAS on anti-GBM-disease and antibody kinetics. To examine the long-term effect of high-frequency IAS combined with standard immunosuppression on patient and renal survival in patients with anti-GBM-disease and to quantify antibody removal and kinetics through IAS. Retrospective review of patients treated with IAS for anti-GBM-antibody disease confirmed by biopsy and/or anti-GBM-antibodies. University Hospital of Vienna, Austria. 10 patients with anti-GBM-disease treated with IAS. Patient and renal survival, renal histology, anti-GBM-antibodies. Anti-GBM-antibodies were reduced by the first 9 IAS treatments (mean number of 23) to negative levels in all patients. Renal survival was 40% at diagnosis, 70% after the end of IAS, 63% after one year and 50% at the end of observation (mean 84 months, range 9 to 186). Dialysis dependency was successfully reversed in three of six patients. Patient survival was 90% at the end of observation. IAS efficiently eliminates anti-GBM-antibodies suggesting non-inferiority to PE with regard to renal and patient survival. Hence IAS should be considered as a valuable treatment option for anti-GBM-disease, especially in patients presenting with a high percentage of crescents and dialysis dependency due to an unusual high proportion of responders.

Long-term outcome of anti-glomerular basement membrane antibody disease treated with immunoadsorption.

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Peter Biesenbach

Full Text Available Anti-glomerular basement membrane (GBM antibody disease may lead to acute crescentic glomerulonephritis with poor renal prognosis. Current therapy favours plasma exchange (PE for removal of pathogenic antibodies. Immunoadsorption (IAS is superior to PE regarding efficiency of antibody-removal and safety. Apart from anecdotal data, there is no systemic analysis of the long-term effects of IAS on anti-GBM-disease and antibody kinetics.To examine the long-term effect of high-frequency IAS combined with standard immunosuppression on patient and renal survival in patients with anti-GBM-disease and to quantify antibody removal and kinetics through IAS.Retrospective review of patients treated with IAS for anti-GBM-antibody disease confirmed by biopsy and/or anti-GBM-antibodies.University Hospital of Vienna, Austria.10 patients with anti-GBM-disease treated with IAS.Patient and renal survival, renal histology, anti-GBM-antibodies.Anti-GBM-antibodies were reduced by the first 9 IAS treatments (mean number of 23 to negative levels in all patients. Renal survival was 40% at diagnosis, 70% after the end of IAS, 63% after one year and 50% at the end of observation (mean 84 months, range 9 to 186. Dialysis dependency was successfully reversed in three of six patients. Patient survival was 90% at the end of observation.IAS efficiently eliminates anti-GBM-antibodies suggesting non-inferiority to PE with regard to renal and patient survival. Hence IAS should be considered as a valuable treatment option for anti-GBM-disease, especially in patients presenting with a high percentage of crescents and dialysis dependency due to an unusual high proportion of responders.

Kinetics of Anti-Phlebotomus perniciosus Saliva Antibodies in Experimentally Bitten Mice and Rabbits.

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Inés Martín-Martín

Full Text Available Sand flies are hematophagous arthropods that act as vectors of Leishmania parasites. When hosts are bitten they develop cellular and humoral responses against sand fly saliva. A positive correlation has been observed between the number of bites and antibody levels indicating that anti-saliva antibody response can be used as marker of exposure to sand flies. Little is known about kinetics of antibodies against Phlebotomus perniciosus salivary gland homogenate (SGH or recombinant salivary proteins (rSP. This work focused on the study of anti-P. perniciosus saliva antibodies in sera of mice and rabbits that were experimentally exposed to the bites of uninfected sand flies.Anti-saliva antibodies were evaluated by ELISA and Western blot. In addition, antibody levels against two P. perniciosus rSP, apyrase rSP01B and D7 related protein rSP04 were determined in mice sera. Anti-saliva antibody levels increased along the immunizations and correlated with the number of sand fly bites. Anti-SGH antibody levels were detected in sera of mice five weeks after exposure, and persisted for at least three months. Anti-apyrase rSP01B antibodies followed similar kinetic responses than anti-SGH antibodies while rSP04 showed a delayed response and exhibited a greater variability among sera of immunized mice. In rabbits, anti-saliva antibodies appeared after the second week of exposure and IgG antibodies persisted at high levels, even 7 months post-exposure.Our results contributed to increase the knowledge on the type of immune response P. perniciosus saliva and individual proteins elicited highlighting the use of rSP01B as an epidemiological marker of exposure. Anti-saliva kinetics in sera of experimentally bitten rabbits were studied for the first time. Results with rabbit model provided useful information for a better understanding of the anti-saliva antibody levels found in wild leporids in the human leishmaniasis focus in the Madrid region, Spain.

Impact of pretransplant anti-HLA antibodies on outcomes in lung transplant candidates.

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Kim, Miae; Townsend, Keri R; Wood, Isabelle G; Boukedes, Steve; Guleria, Indira; Gabardi, Steven; El-Chemaly, Souheil; Camp, Phillip C; Chandraker, Anil K; Milford, Edgar L; Goldberg, Hilary J

2014-05-15

The prevalence of anti-HLA antibodies in lung transplant candidates and their impact on waitlist and transplant outcomes is not known. We examined the prevalence of pretransplant anti-HLA antibodies at varying thresholds and evaluated their impact on outcomes before and after lung transplantation. We performed a single-center retrospective cohort study including all patients listed for lung transplantation between January 2008 and August 2012. Per protocol, transplant candidates were assessed by solid phase LABscreen mixed Class I and II and LABscreen Single Antigen assays. Among 224 patients, 34% had anti-HLA antibodies at mean fluorescent intensity (MFI) greater than or equal to 3,000 (group III), and 24% had antibodies at MFI 1,000 to 3,000 (group II). Ninety percent of the patients with pretransplant anti-HLA antibodies had class I antibodies, whereas only seven patients developed class II alone. Patients in group III were less likely to receive transplants than patients without any anti-HLA antibodies (group I) (45.5 vs. 67.7%, P = 0.005). Wait time to transplant was longer in group III than group I, although this difference did not meet statistical significance, and waitlist mortality was similar. Among transplant recipients, antibody-mediated rejection (AMR) was more frequent in group III than in group II (20% vs. 0%, P = 0.01) or group I (6.3%, P = 0.05). The presence of anti-HLA antibodies at the high MFI threshold (>3,000) was associated with lower transplant rate and higher rates of AMR. Screening for anti-HLA antibodies using the 3,000 MFI threshold may be important in managing transplant candidates and recipients.

Anti-phospholipid antibodies in patients with Plasmodium falciparum malaria

DEFF Research Database (Denmark)

Jakobsen, P H; Morris-Jones, S D; Hviid, L

1993-01-01

Plasma levels of antibodies against phosphatidylinositol (PI), phosphatidylcholine (PC) and cardiolipin (CL) were measured by enzyme-linked immunosorbent assay (ELISA) in patients from malaria endemic area of Sudan and The Gambia. Some Sudanese adults produced IgM antibodies against all three types...... of phospholipids (PL) during an acute Plasmodium falciparum infection. The anti-PL antibody titre returned to preinfection levels in most of the donors 30 days after the disease episode. IgG titres against PI, PC and CL were low. In Gambian children with malaria, IgM antibody titres against PI and PC were...... significantly higher in those with severe malaria than in those with mild malaria. These results show that a proportion of malaria patients produce anti-PL antibodies during infection and that titres of these antibodies are associated with the severity of disease....

Localization studies of metastatic axillary lymph node by radioimmunoimmaging with monoclonal antibody C50 in breast cancer

International Nuclear Information System (INIS)

Feng Jue; Gao Yougong

1993-01-01

Eleven patients with breast cancer and 2 normal controls (26 axillary lymph-nodes) were studied by the radio immunoimaging with 131 I labelled anti-CEA monoclonal antibody C 50 . Among them, the imaging was positive in 8 patients and negative in 3 patients. 7 of the 8 positive patients were proven by the pathological examination of postoperative lymph nodes. Other one had proved with the presence of CEA-antigen and antigen-antibody immuno complexes in the lymphoid sinus by immuno histochemistry. Cancer cell was not found by pathology in the axillary lymph node of 3 negative imaging patients. 2 normal controls was also negative

Anti-JC virus antibody prevalence in a multinational multiple sclerosis cohort

DEFF Research Database (Denmark)

Olsson, Tomas; Achiron, Anat; Alfredsson, Lars

2013-01-01

JC virus (JCV) is an opportunistic virus known to cause progressive multifocal leukoencephalopathy. Anti-JC virus (Anti-JCV) antibody prevalence in a large, geographically diverse, multi-national multiple sclerosis (MS) cohort was compared in a cross-sectional study. Overall, anti-JCV antibody...... prevalence was 57.6%. Anti-JCV antibody prevalence in MS patients ranged from approximately 47% to 68% across these countries: Norway, 47.4%; Denmark, 52.6%; Israel, 56.6%; France, 57.6%; Italy, 58.3%; Sweden, 59.0%; Germany, 59.1%; Austria, 66.7% and Turkey, 67.7%. Prevalence increased with age (from 49...

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

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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

Anti-nucleosome antibodies in systemic lupus erythematosus patients: Relation to anti-double stranded deoxyribonucleic acid and disease activity

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Mayada Ali Abdalla

2018-01-01

Conclusion: Anti-NCS antibodies could play a role in the pathogenesis of SLE and is related to disease activity. Its association with anti-dsDNA antibodies and its presence in those with negative anti-ds DNA may aid in the diagnosis of SLE.

Unexplained infertility: identification of anti sperm antibodies using radiometric immunoassay

International Nuclear Information System (INIS)

Megahed, Y.M.; Elnabarawy, F.; Hamada, T.; Ayiad, S.K.

1992-01-01

Several methods have been employed to measure anti sperm antibodies with variable sensitivity and specificity in serum and secretion of infertile patients. All of them are not precise means for identification of the presence of anti sperm antibodies for patients with unexplained infertility (Haas et al, 1980). Therefore, the modified radiolabelled anti globulin test, that has been used successfully to identify and quantitate the antibodies directed towards other human cell surfaces, was applied. A total number of 128 subjects in different groups were studied to quantitate the circulating anti sperm antibodies using the modified procedure. The present data revealed that the highest and the most significant incidence were found in the patients secretions (semen and cervical mucus) with unexplained infertility, as well as in the group of males with varicocele. Therefore it is greatly advisable to use the modified radiolabelled technique as a quantitative assay, which will be helpful in management of infertility in patients with unexplained and mediated infertility.3 tab., 4 fig

Pre-existing anti-HLA antibodies negatively impact survival of pediatric aplastic anemia patients undergoing HSCT.

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Zhu, Hua; He, Jun; Cai, Junchao; Yuan, Xiaoni; Jiang, Hua; Luo, Changying; Wang, Jianmin; Luo, Chengjuan; Pan, Zhijuan; Terasaki, Paul I; Ding, Lixia; Chen, Jing

2014-11-01

Graft failure and survival are the major problems for patients with aplastic anemia undergoing hematopoietic stem cell transplantation (HSCT). Previous studies showed that anti-HLA antibodies negatively impact engraftment in HSCT. This retrospective study of 51 pediatric patients with acquired aplastic anemia who underwent allogeneic HSCT at a single institution between 2006 and 2012 investigated the influence of anti-HLA antibodies on the outcome of HSCT. Serum samples collected before HSCT were tested for the presence of anti-HLA antibodies. Pre-existing anti-HLA antibodies were detected in 54.9% (28/51) of patients, among whom 39.2% (20/51) had anti-HLA class I antibodies. Anti-HLA antibodies were associated with worse five-yr survival (78.6% vs. 100%, p = 0.021) and higher treatment-related mortality (21.4% vs. 0%, p = 0.028) compared with antibody-negative patients. Anti-HLA class I antibody-positive patients had poorer five-yr survival (75.0%) than anti-HLA class I&II antibody-positive and antibody-negative patients (87.5% and 100.0%, respectively, p = 0.039). Presence of anti-HLA class I antibodies (p = 0.024) and older age (10 yr or more; p = 0.027) significantly increased the risk of post-HSCT mortality. Pre-existing anti-HLA antibodies negatively affect the outcome of HSCT in pediatric patients with aplastic anemia. Routine testing for anti-HLA antibodies concurrent with efficient treatment should be conducted prior to HSCT. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Idiotypic network. Assay and use of anti-idiotype antibodies in medicine

International Nuclear Information System (INIS)

Revillard, J.P.; Oliva, Ph.

1988-01-01

After a brief history of idotypes, the structural basis of antibody and T cell receptor (Ti) diversity, the definition of various types of idiotopes, the idiotypic cascade and the network concept are presented. Some anti-idiotypic antibodies represent the internal image of the antigen and may be used to prepare anti-idiotypic vaccines. Other anti-idiotypic antibodies bind to cellular receptors and can mimick or antagonize the biological effects of the natural ligands (hormones, neurotransmitters etc...). The concept of regulatory idiotopes (Idx) and their use in the manipulation of the network offer new possibilities for the control for auto-antibody production. The main medical applications of idiotypy are briefly considered including cancer, transplantation, allergy and auto-immune diseases. Finally the methodology applicable to the detection and titration of anti-idiotypes is described [fr

SU-E-T-45: Antibody Mean Residence Time in Blood and Its Correlation with Protein Molecular Weight

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

2014-06-01

Purpose: Animal biodistribution data are required prior to introducing a new radiopharmaceutical into clinical trials. Protein engineering, using recombinant DNA techniques can produce a large number of related (cognate) antibodies to a given molecular target. Thus, it is important that these constructs be numerically related to one another via a single criterion. In the following, we use the mean residence time (MRT) in murine blood as this criterion. Methods: Five cognate anti-CEA (Carcinoembryonic Antigen) antibodies were compared with regard to their MRT in whole blood of CEA-positive tumor-bearing (LS174T) mice. MRT was defined by blood AUC (area under the curve) divided by the initial blood uptake value; all in units of percent injected dose per gram (%ID/g). Cognates included single chain scFv (25 kDa), diabody (50 kDa), minibody (80 kDa), F(ab')2 (120 kDa), and intact (155 kDa) forms of the murine cT84.66 antibody against CEA. All were labeled with radioactive iodine. Results: The agents, in the sequence listed, exhibited MRT values of 1.16 +/- 0.01 h, 0.99 h, 5.06 +/- 0.70 h, 6.61 +/- 0.36 h, and 59.3 +/- 2.4 h respectively. Because of the monotonic nature of the sequence, a linear correlation analysis was performed between molecular weight (MW) and MRT or ln(MRT) of the 5 proteins. Probability of random correlation was 0.10 for MRT and 0.01 for ln(MRT). Conclusion: MRT values of cognate anti-CEA antibodies were found to be a monotonically increasing sequence with respect to MW. Cognate MW values correlated best to ln(MRT) of the protein species. Thus MRT was proportional to an exponential function of molecular weight. The extended intact antibody circulation time presumably reflected its relatively maximal MW. Presence of an intact FC segment on this native antibody may also have influenced these results.

SU-E-T-45: Antibody Mean Residence Time in Blood and Its Correlation with Protein Molecular Weight

International Nuclear Information System (INIS)

Kwok, C; Williams, L

2014-01-01

Purpose: Animal biodistribution data are required prior to introducing a new radiopharmaceutical into clinical trials. Protein engineering, using recombinant DNA techniques can produce a large number of related (cognate) antibodies to a given molecular target. Thus, it is important that these constructs be numerically related to one another via a single criterion. In the following, we use the mean residence time (MRT) in murine blood as this criterion. Methods: Five cognate anti-CEA (Carcinoembryonic Antigen) antibodies were compared with regard to their MRT in whole blood of CEA-positive tumor-bearing (LS174T) mice. MRT was defined by blood AUC (area under the curve) divided by the initial blood uptake value; all in units of percent injected dose per gram (%ID/g). Cognates included single chain scFv (25 kDa), diabody (50 kDa), minibody (80 kDa), F(ab')2 (120 kDa), and intact (155 kDa) forms of the murine cT84.66 antibody against CEA. All were labeled with radioactive iodine. Results: The agents, in the sequence listed, exhibited MRT values of 1.16 +/- 0.01 h, 0.99 h, 5.06 +/- 0.70 h, 6.61 +/- 0.36 h, and 59.3 +/- 2.4 h respectively. Because of the monotonic nature of the sequence, a linear correlation analysis was performed between molecular weight (MW) and MRT or ln(MRT) of the 5 proteins. Probability of random correlation was 0.10 for MRT and 0.01 for ln(MRT). Conclusion: MRT values of cognate anti-CEA antibodies were found to be a monotonically increasing sequence with respect to MW. Cognate MW values correlated best to ln(MRT) of the protein species. Thus MRT was proportional to an exponential function of molecular weight. The extended intact antibody circulation time presumably reflected its relatively maximal MW. Presence of an intact FC segment on this native antibody may also have influenced these results

Anti-N-methyl-D-aspartate receptor encephalitis with serum anti-thyroid antibodies and IgM antibodies against Epstein-Barr virus viral capsid antigen: a case report and one year follow-up

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Xu Chun-Ling

2011-11-01

Full Text Available Abstract Background Anti-N-methyl-D-aspartate receptor encephalitis is an increasingly common autoimmune disorder mediated by antibodies to certain subunit of the N-methyl-D-aspartate receptor. Recent literatures have described anti-thyroid and infectious serology in this encephalitis but without follow-up. Case presentation A 17-year-old Chinese female patient presented with psychiatric symptoms, memory deficits, behavioral problems and seizures. She then progressed through unresponsiveness, dyskinesias, autonomic instability and central hypoventilation during treatment. Her conventional blood work on admission showed high titers of IgG antibodies to thyroglobulin, thyroid peroxidase and IgM antibodies to Epstein-Barr virus viral capsid antigen. An immature ovarian teratoma was found and removal of the tumor resulted in a full recovery. The final diagnosis of anti-N-methyl-D-aspartate receptor encephalitis was made by the identification of anti-N-methyl-D-aspartate receptor antibodies in her cerebral spinal fluid. Pathology studies of the teratoma revealed N-methyl-D-aspartate receptor subunit 1 positive ectopic immature nervous tissue and Epstein-Barr virus latent infection. She was discharged with symptoms free, but titers of anti-thyroid peroxidase and anti-thyroglobulin antibodies remained elevated. One year after discharge, her serum remained positive for anti-thyroid peroxidase and anti-N-methyl-D-aspartate receptor antibodies, but negative for anti-thyroglobulin antibodies and IgM against Epstein-Barr virus viral capsid antigen. Conclusions Persistent high titers of anti-thyroid peroxidase antibodies from admission to discharge and until one year later in this patient may suggest a propensity to autoimmunity in anti- N-methyl-D-aspartate receptor encephalitis and support the idea that neuronal and thyroid autoimmunities represent a pathogenic spectrum. Enduring anti-N-methyl-D-aspartate receptor antibodies from admission to one year

Intravitreally Injected Anti-VEGF Antibody Reduces Brown Fat in Neonatal Mice.

Science.gov (United States)

Jo, Dong Hyun; Park, Sung Wook; Cho, Chang Sik; Powner, Michael B; Kim, Jin Hyoung; Fruttiger, Marcus; Kim, Jeong Hun

2015-01-01

Anti-vascular endothelial growth factor (VEGF) agents are the mainstay treatment for various angiogenesis-related retinal diseases. Currently, bevacizumab, a recombinant humanized anti-VEGF antibody, is trailed in retinopathy of prematurity, a vasoproliferative retinal disorder in premature infants. However, the risks of systemic complications after intravitreal injection of anti-VEGF antibody in infants are not well understood. In this study, we show that intravitreally injected anti-VEGF antibody is transported into the systemic circulation into the periphery where it reduces brown fat in neonatal C57BL/6 mice. A considerable amount of anti-VEGF antibody was detected in serum after intravitreal injection. Furthermore, in interscapular brown adipose tissue, we found lipid droplet accumulation, decreased VEGF levels, loss of vascular network, and decreased expression of mitochondria-related genes, Ppargc1a and Ucp1, all of which are characteristics of "whitening" of brown fat. With increasing age and body weight, brown fat restored its morphology and vascularity. Our results show that there is a transient, but significant impact of intravitreally administered anti-VEGF antibody on brown adipose tissue in neonatal mice. We suggest that more attention should be focused on the metabolic and developmental significance of brown adipose tissue in bevacizumab treated retinopathy of prematurity infants.

Intravitreally Injected Anti-VEGF Antibody Reduces Brown Fat in Neonatal Mice.

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Dong Hyun Jo

Full Text Available Anti-vascular endothelial growth factor (VEGF agents are the mainstay treatment for various angiogenesis-related retinal diseases. Currently, bevacizumab, a recombinant humanized anti-VEGF antibody, is trailed in retinopathy of prematurity, a vasoproliferative retinal disorder in premature infants. However, the risks of systemic complications after intravitreal injection of anti-VEGF antibody in infants are not well understood. In this study, we show that intravitreally injected anti-VEGF antibody is transported into the systemic circulation into the periphery where it reduces brown fat in neonatal C57BL/6 mice. A considerable amount of anti-VEGF antibody was detected in serum after intravitreal injection. Furthermore, in interscapular brown adipose tissue, we found lipid droplet accumulation, decreased VEGF levels, loss of vascular network, and decreased expression of mitochondria-related genes, Ppargc1a and Ucp1, all of which are characteristics of "whitening" of brown fat. With increasing age and body weight, brown fat restored its morphology and vascularity. Our results show that there is a transient, but significant impact of intravitreally administered anti-VEGF antibody on brown adipose tissue in neonatal mice. We suggest that more attention should be focused on the metabolic and developmental significance of brown adipose tissue in bevacizumab treated retinopathy of prematurity infants.

Anti-Jo-1 antibody-positive patients show a characteristic necrotizing perifascicular myositis.

Science.gov (United States)

Mescam-Mancini, Lénaig; Allenbach, Yves; Hervier, Baptiste; Devilliers, Hervé; Mariampillay, Kuberaka; Dubourg, Odile; Maisonobe, Thierry; Gherardi, Romain; Mezin, Paulette; Preusse, Corinna; Stenzel, Werner; Benveniste, Olivier

2015-09-01

Idiopathic inflammatory myopathies can be classified as polymyositis, dermatomyositis, immune-mediated necrotizing myopathy, sporadic inclusion body myositis or non-specific myositis. Anti-Jo-1 antibody-positive patients are assigned to either polymyositis or dermatomyositis suggesting overlapping pathological features. We aimed to determine if anti-Jo-1 antibody-positive myopathy has a specific morphological phenotype. In a series of 53 muscle biopsies of anti-Jo-1 antibody-positive patients, relevant descriptive criteria defining a characteristic morphological pattern were identified. They were tested in a second series of anti-Jo-1 antibody-positive patients and compared to 63 biopsies from patients suffering from other idiopathic inflammatory myopathies. In anti-Jo-1 antibody-positive patients, necrotic fibres, which strongly clustered in perifascicular regions, were frequently observed. Sarcolemmal complement deposition was detected specifically in perifascicular areas. Inflammation was mainly located in the perimysium and around vessels in 90.6%. Perimysial fragmentation was observed in 90% of cases. Major histocompatibility complex class I staining was diffusely positive, with a perifascicular reinforcement. Multivariate analysis showed that criteria defining perifascicular pathology: perifascicular necrosis, atrophy, and perimysial fragmentation allow the distinction of anti-Jo-1 antibody-positive patients, among patients suffering from other idiopathic inflammatory myopathies. Anti-Jo-1 antibody-positive patients displayed perifascicular necrosis, whereas dermatomyositis patients exhibited perifascicular atrophy. © The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Efficient tumor regression by adoptively transferred CEA-specific CAR-T cells associated with symptoms of mild cytokine release syndrome.

Science.gov (United States)

Wang, Linan; Ma, Ning; Okamoto, Sachiko; Amaishi, Yasunori; Sato, Eiichi; Seo, Naohiro; Mineno, Junichi; Takesako, Kazutoh; Kato, Takuma; Shiku, Hiroshi

2016-01-01

Carcinoembryonic antigen (CEA) is a cell surface antigen highly expressed in various cancer cell types and in healthy tissues. It has the potential to be a target for chimeric antigen receptor (CAR)-modified T-cell therapy; however, the safety of this approach in terms of on-target/off-tumor effects needs to be determined. To address this issue in a clinically relevant model, we used a mouse model in which the T cells expressing CEA-specific CAR were transferred into tumor-bearing CEA-transgenic (Tg) mice that physiologically expressed CEA as a self-antigen. The adoptive transfer in conjunction with lymphodepleting and myeloablative preconditioning mediated significant tumor regression but caused weight loss in CEA-Tg, but not in wild-type mice. The weight loss was not associated with overt inflammation in the CEA-expressing gastrointestinal tract but was associated with malnutrition, reflected in elevated systemic levels of cytokines linked to anorexia, which could be controlled by the administration of an anti-IL-6 receptor monoclonal antibody without compromising efficacy. The apparent relationship between lymphodepleting and myeloablative preconditioning, efficacy, and off-tumor toxicity of CAR-T cells would necessitate the development of CEA-specific CAR-T cells with improved signaling domains that require less stringent preconditioning for their efficacy. Taken together, these results suggest that CEA-specific CAR-based adoptive T-cell therapy may be effective for patients with CEA + solid tumors. Distinguishing the fine line between therapeutic efficacy and off-tumor toxicity would involve further modifications of CAR-T cells and preconditioning regimens.

Clinically significant anti M antibodies--a report of two cases.

Science.gov (United States)

Kaur, Gagandeep; Basu, Sabita; Kaur, Paramjit; Kaur, Ravneet

2012-12-01

Most anti-M antibodies are not active at 37°C and are thus of no clinical significance. Occasionally these antibodies have a wide thermal range and can lead to hemolytic transfusion reactions or hemolytic disease of the new born. We describe two cases of anti-M antibodies, both of which were clinically significant. The first case was detected due to crossmatch incompatibility and the second presented as a blood group discrepancy. When the antibody is active at 37°C, M antigen negative red cell units should be issued. Copyright © 2012 Elsevier Ltd. All rights reserved.

Anti-G antibody in alloimmunized pregnant women: Report of two cases

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Raj Nath Makroo

2015-01-01

Full Text Available Anti-G has been reported as a possible cause of hemolytic disease of the fetus and newborn (HDFN, either independently or in association with anti-D, anti-C or both. The antibody mimics the pattern of anti-C and anti-D reactivity in the identification panel and is often present along with either or both of these antibodies. The differentiation of anti-D, -C and-G in routine pretransfusion workup is particularly essential in antenatal cases. We report two antenatal cases where anti-G was identified on advanced immunohematological workup, in addition to other alloantibodies.

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)

Clinico-laboratory aspects of anti-nuclear and anti-native DNA antibody tests.

Science.gov (United States)

Webb, J

1978-01-01

Available techniques for detection of anti-nuclear antibodies are here briefly reviewed. The relatively insensitive LE cell test has been largely supplanted by the indirect immunofluorescent ANA test which should be reported in terms of titre and pattern. Specific measurement of nDNA antibodies is now a regular technique in SLE diagnosis and management.

[Role of anti c-mpl antibody in systemic lupus erythematosus with thrombocytopenia].

Science.gov (United States)

Yang, Tuo; Huang, Ci Bo; Lai, Bei; Zhao, Li Ke; Chen, Ying Juan; Zhao, Yue Tao; Zhang, Chun Mei; Zeng, Xiao Feng

2012-04-18

To determine whether anti-thrompoietin receptor (TPO-R, c-mpl) antibody contributes to thrombocytopenia in systemic lupus erytematosus (SLE) and explore the pathogenic role of this antibody. Sera from 24 SLE patients with thrombocytopenia, 27 SLE patients having normal platelet counts with a history of thrombocytopenia, 18 SLE patients with neither thrombocytopenia nor post thrombocytopenia and 18 healthy controls were collected. Anti c-mpl antibodies were detected by an indirected ELISA assay. The serum TPO levels were measured by an ELISA assay. Clinical findings, autoantibody profiles, and SLEDAI were evaluated. Serum anti c-mpl antibodies were detected in 18.8% of the SLE patientis. The frequency of this antibody in SLE with thrombocytopenia, SLE with a history of thrombocytopenia and SLE without thrombocytopenia were of no difference (P=0.600). In the patients with anti c-mpl antibodies, their platelet counts were decreased(P=0.025) and serum TPO levels elevated(P=0.038) than those in the patients without, while there were no differences between the two groups in C3, C4, ESR, CRP level, the frequency of ANA, dsDNA, ANCA and SLEDAI. Anti c-mpl antibody contributes to SLE-associated thrombocytopenia by functionally blocking an interaction between thrombopoietin and c-mpl, which might inhibit TPO-dependent megakaryocyte proliferation and differentiation.

Sero-Prevalence of anti-sperm anti-bodies in infertile males in Port ...

African Journals Online (AJOL)

Background: Infertility is a serious health challenge which causes distress to the couples especially; in Africa. The cause of infertility is multifactorial. Immunological infertility is said to be one of the major causes of unexplained infertility in men. Anti-sperm anti-bodies can be used as an immunological marker of infertility.

Anti-DNA antibodies: Sequencing, cloning, and expression

Energy Technology Data Exchange (ETDEWEB)

Barry, M.M.

1992-01-01

To gain some insight into the mechanism of systemic lupus erythematosus, and the interactions involved in proteins binding to DNA four anti-DNA antibodies have been investigated. Two of the antibodies, Hed 10 and Jel 242, have previously been prepared from female NZB/NZW mice which develop an autoimmune disease resembling human SLE. The remaining two antibodies, Jel 72 and Jel 318, have previously been produced via immunization of C57BL/6 mice. The isotypes of the four antibodies investigated in this thesis were determined by an enzyme-linked-immunosorbent assay. All four antibodies contained [kappa] light chains and [gamma]2a heavy chains except Jel 318 which contains a [gamma]2b heavy chain. The complete variable regions of the heavy and light chains of these four antibodies were sequenced from their respective mRNAs. The gene segments and variable gene families expressed in each antibody were identified. Analysis of the genes used in the autoimmune anti-DNA antibodies and those produced by immunization indicated no obvious differences to account for their different origins. Examination of the amino acid residues present in the complementary-determining regions of these four antibodies indicates a preference for aromatic amino acids. Jel 72 and Jel 242 contain three arginine residues in the third complementary-determining region. A single-chain Fv and the variable region of the heavy chain of Hed 10 were expressed in Escherichia coli. Expression resulted in the production of a 26,000 M[sub r] protein and a 15,000 M[sub r] protein. An immunoblot indicated that the 26,000 M[sub r] protein was the Fv for Hed 10, while the 15,000 M[sub r] protein was shown to bind poly (dT). The contribution of the heavy chain to DNA binding was assessed.

Comparative tumour localization properties of radiolabelled monoclonal antibody preparations of defined immunoreactivities

International Nuclear Information System (INIS)

Pimm, M.V.; Baldwin, R.W.

1987-01-01

The immunoreactive fraction of an anti-CEA monoclonal antibody preparation has been progressively decreased by the addition of increasing proportions of impurity in the form of immunologically inert mouse immunoglobulin. Following radioiodination, the immunoreactive fractions of the preparations were determined and their localization in a human tumour xenograft in nude mice was assessed. There was a progressive decline in tumour localization, from tumour to blood ratios of 2:1 with unadulterated antibody to 0.6:1 with preparations only 15% with respect to the initial antibody. These findings demonstrate that the immunoreactive fraction of monoclonal antibody preparations is a major limiting factor in tumour localization and this has implications for experimental and clinical applications of monoclonal antibodies. (orig.)

Anti-Chol-1 antigen, GQ1bα, antibodies are associated with Alzheimer's disease.

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Toshio Ariga

Full Text Available The interaction of amyloid β-proteins (Aβ with membrane gangliosides has been reported to be an early event in Aβ fibril formation in Alzheimer's disease (AD. Neuronal degeneration in AD has been postulated to be associated with the presence of anti-ganglioside antibodies in patient sera. Using an enzyme-linked immunosorbent assay (ELISA and high-performance thin-layer chromatography (HPTLC immunostaining, sera from 27 individuals (10 with AD, 6 with vascular dementia (VD, and 11 non-demented age-matched pathological controls were examined in order to detect anti-glycosphingolipid (GSL antibodies, including anti-cholinergic-specific antigen (Chol-1α; GQ1bα antibodies. All sera had natural antibodies against ganglio-N-tetraosyl gangliosides (brain-type gangliosides. However, sera of demented patients with AD and VD had significantly higher titers of anti-GSL antibodies than those in age-matched pathological controls. Although most serum antibodies, including anti- GM1, -GT1b, -GQ1b, -GQ1bα, were of the IgM type, the presence of the IgG type antibodies was also significantly elevated in the sera of demented patients with AD. Anti-GT1b antibodies of the IgG type were elevated in AD (90%, 9 of 10 cases and VD (100%, respectively. Most surprisingly, anti-GQ1bα antibodies (IgM were found in 90% (9/10 and 100% (6/6 in the sera of patients with AD and VD, respectively. Since GQ1bα is present in the cerebral cortex and hippocampus, the presence of anti-GQ1bα antibodies may play an important role in disrupting cholinergic synaptic transmission and may participate in the pathogenesis of dementia. We conclude that elevated anti-GSL antibody titers may be useful as an aid for clinical diagnosis of those dementias.

Clinical significance of anti-domain 1 β2-glycoprotein I antibodies in antiphospholipid syndrome.

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Iwaniec, Teresa; Kaczor, Marcin P; Celińska-Löwenhoff, Magdalena; Polański, Stanisław; Musiał, Jacek

2017-05-01

Antiphospholipid syndrome (APS) is characterized by the presence of circulating antiphospholipid antibodies (aPL) in patients with thrombosis and/or pregnancy morbidity. In APS patients anti-domain 1 β2-glycoprotein I (anti-D1 β2GPI) IgG antibodies correlate strongly with thrombosis and to the lesser extent, with pregnancy complications. The aim of this study was to assess clinical utility of the anti-D1 β2GPI antibodies in the diagnosis and risk stratification of antiphospholipid syndrome. In this retrospective study 202 autoimmune patients were studied (primary APS - 58, secondary - 45 SLE - 99). Anticardiolipin (aCL) and anti-β 2 GPI (aβ 2 GPI antibodies) (IgG and IgM class) together with anti-D1 IgG were tested with QUANTA Flash chemiluminescent immunoassay and lupus anticoagulant (LA) with coagulometric methods. The highest anti-D1 values were observed in triple positive patients as compared to patients with other antiphospholipid antibody profiles. A strong correlation was found between levels of anti-D1 IgG and a β2GPI IgG antibodies for all patients analyzed (Spearman's ρ=0.87; p<0.0001). Anti-D1 IgG antibodies increase specificity resulting from classic aPL positivity but at the expense of sensitivity. Anti-D1 test does not add accuracy in predicting APS thrombotic complications on the top of accuracy offered by classic aPL tests and their profiles. Anti-D1 IgG antibodies did not add diagnostic power to the standard laboratory aPL tests as assessed by this retrospective study. A true clinical significance of anti-D1 antibodies in thrombotic risk stratification of aPL positive patients will require a properly designed clinical prospective trials. Copyright © 2017 Elsevier Ltd. All rights reserved.

Glutamate receptor antibodies in neurological diseases: anti-AMPA-GluR3 antibodies, anti-NMDA-NR1 antibodies, anti-NMDA-NR2A/B antibodies, anti-mGluR1 antibodies or anti-mGluR5 antibodies are present in subpopulations of patients with either: epilepsy, encephalitis, cerebellar ataxia, systemic lupus erythematosus (SLE) and neuropsychiatric SLE, Sjogren's syndrome, schizophrenia, mania or stroke. These autoimmune anti-glutamate receptor antibodies can bind neurons in few brain regions, activate glutamate receptors, decrease glutamate receptor's expression, impair glutamate-induced signaling and function, activate blood brain barrier endothelial cells, kill neurons, damage the brain, induce behavioral/psychiatric/cognitive abnormalities and ataxia in animal models, and can be removed or silenced in some patients by immunotherapy.

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Levite, Mia

2014-08-01

Glutamate is the major excitatory neurotransmitter of the Central Nervous System (CNS), and it is crucially needed for numerous key neuronal functions. Yet, excess glutamate causes massive neuronal death and brain damage by excitotoxicity--detrimental over activation of glutamate receptors. Glutamate-mediated excitotoxicity is the main pathological process taking place in many types of acute and chronic CNS diseases and injuries. In recent years, it became clear that not only excess glutamate can cause massive brain damage, but that several types of anti-glutamate receptor antibodies, that are present in the serum and CSF of subpopulations of patients with a kaleidoscope of human neurological diseases, can undoubtedly do so too, by inducing several very potent pathological effects in the CNS. Collectively, the family of anti-glutamate receptor autoimmune antibodies seem to be the most widespread, potent, dangerous and interesting anti-brain autoimmune antibodies discovered up to now. This impression stems from taking together the presence of various types of anti-glutamate receptor antibodies in a kaleidoscope of human neurological and autoimmune diseases, their high levels in the CNS due to intrathecal production, their multiple pathological effects in the brain, and the unique and diverse mechanisms of action by which they can affect glutamate receptors, signaling and effects, and subsequently impair neuronal signaling and induce brain damage. The two main families of autoimmune anti-glutamate receptor antibodies that were already found in patients with neurological and/or autoimmune diseases, and that were already shown to be detrimental to the CNS, include the antibodies directed against ionotorpic glutamate receptors: the anti-AMPA-GluR3 antibodies, anti-NMDA-NR1 antibodies and anti-NMDA-NR2 antibodies, and the antibodies directed against Metabotropic glutamate receptors: the anti-mGluR1 antibodies and the anti-mGluR5 antibodies. Each type of these anti

Limbic encephalitis associated with anti-NH2-terminal of α-enolase antibodies

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Kishitani, Toru; Matsunaga, Akiko; Ikawa, Masamichi; Hayashi, Kouji; Yamamura, Osamu; Hamano, Tadanori; Watanabe, Osamu; Tanaka, Keiko; Nakamoto, Yasunari; Yoneda, Makoto

2017-01-01

Abstract Several types of autoantibodies have been reported in autoimmune limbic encephalitis (LE), such as antibodies against the voltage-gated potassium channel (VGKC) complex including leucine-rich glioma inactivated 1 (LGI1). We recently reported a patient with autoimmune LE and serum anti-NH2-terminal of α-enolase (NAE) antibodies, a specific diagnostic marker for Hashimoto encephalopathy (HE), who was diagnosed with HE based on the presence of antithyroid antibodies and responsiveness to immunotherapy. This case suggests that LE patients with antibodies to both the thyroid and NAE could be diagnosed with HE and respond to immunotherapy. The aim of this study was to clarify the clinicoimmunological features and efficacy of immunotherapy in LE associated with anti-NAE antibodies to determine whether the LE is a clinical subtype of HE. We examined serum anti-NAE antibodies in 78 LE patients with limbic abnormality on magnetic resonance imaging and suspected HE based on positivity for antithyroid antibodies. Nineteen of the 78 patients had anti-NAE antibodies; however, 5 were excluded because they were double positive for antibodies to the VGKC complex including LGI1. No antibodies against the N-methyl-D-aspartate receptor (NMDAR), contactin-associated protein 2 (Caspr2), γ-aminobutyric acid-B receptor (GABABR), or α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor (AMPAR) were detected in the 19 patients. Among the remaining 14 who were positive only for anti-NAE antibodies, the median age was 62.5 (20–83) years, 9 (64%) were women, and 8 (57%) showed acute onset, with less than 2 weeks between onset and admission. Consciousness disturbance (71%) and memory disturbance (64%) were frequently observed, followed by psychiatric symptoms (50%) and seizures (43%). The frequency of these symptoms significantly differed between the acute- and subacute-onset groups. Abnormalities in cerebrospinal fluid and electroencephalogram were commonly observed (92

Frequency of anti-HCV antibodies in patients with lichen planus

International Nuclear Information System (INIS)

Mahboob, A.; Haroon, T.S.; Iqbal, Z.; Butt, A.K.

2003-01-01

Objective: To determine the frequency of anti-HCV antibodies, identify risk factors associated with HCV infection and to screen asymptomatic carries in patients with lichen planus. Subjects and Methods: A total of 184 clinically diagnosed cased of lichen (LP) were selected for the study. Blood samples of all the patients were tested for anti hepatitis C virus antibodies (anti-HCV-Ab). Polymerase chain reaction for hepatitis C virus was done in patients with positive anti-HCV-Ab. Trancutaneous liver biopsy was performed in 7 patients with positive HCV-RNA. The histopathological results were evaluated using validated Metavir and Knodell scoring systems. Results: Out of 184 LP patients, 43 (23.4%) were anti-HCV antibodies positive. Females were predominantly affected and male to female ratio was 1:5.1. Maximum positively for anti-HCV was observed in age group 31-40 years (39.53%) followed by 41-50 years (25.58%). Eighty-one percent patients had history of dental treatment and 63% had received multiple injections for various ailments. Forty percent patients had family history of jaundice while 26% had jaundice in the past. Ten out of 16 anti-HCV antibody positive patients, checked for HCV-RNA, had high levels of virus in blood. Transcutaneous liver biopsy done in 7 patients revealed underlying liver disease at various stages. Four patients treated with alpha-interferon and ribazole therapy for liver disease, showed marked improvement in their skin disease. Conclusion: A high prevalence of HCV infection was detected in patients with lichen planus. Patients with lichen planus should be screened for HCV carrier state. (author)

Anti-soluble liver antigen (SLA) antibodies in chronic HCV infection.

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Vitozzi, Susana; Lapierre, Pascal; Djilali-Saiah, Idriss; Marceau, Gabriel; Beland, Kathie; Alvarez, Fernando

2004-05-01

Hepatitis C infection is associated with autoimmune disorders, such as the production of autoantibodies. Anti-LKM1 and anti-LC1, immunomarkers of type 2 autoimmune hepatitis, have been previously associated with a HCV infection. Anti-Soluble-Liver-Antigen autoantibodies (SLA) are specifically associated with type 1 and type 2 autoimmune hepatitis and more closely related to patients who relapse after steroid therapy. The recent molecular cloning of the soluble liver antigen provides the opportunity to develop more specific tests for the detection of antibodies against it. The aim of this work is to characterize anti-soluble-liver autoantibodies in sera from patients chronically infected by HCV. A recombinant cDNA from activated Jurkat cells coding for the full length tRNP(Ser)Sec/SLA antigen was obtained. ELISA, Western Blot and immunoprecipitation tests were developed and used to search for linear and conformational epitopes recognized by anti-SLA antibodies in sera from patients chronically infected by HCV. Anti-soluble liver antigen antibodies were found in sera from 10.4% of HCV-infected patients. The prevalence was significantly increased to 27% when anti-LKM1 was also present. Most anti-SLA reactivity was directed against conformational epitopes on the antigen. The means titers by ELISA were lower than those obtained in type 2 AIH. The result of autoantibody isotyping showed a subclass restriction to IgG1 and also IgG4. This study shows the presence of anti-SLA antibodies in approximately 10% of HCV infected patients. The prevalence of SLA autoantibodies in HCV infected patients increases when LKM1 autoantibodies are also present. The relationship between the prevalence of this characteristic autoimmune hepatitis autoantibody and the implication of an autoimmune phenomenon in the liver injury of patients chronically infected by HCV needs further investigation.

A murine monoclonal anti-idiotypic antibody detects a common idiotope on human, mouse and rabbit antibodies to allergen Lol p IV.

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Zhou, E M; Dzuba-Fischer, J M; Rector, E S; Sehon, A H; Kisil, F T

1991-09-01

A syngeneic mouse monoclonal anti-idiotypic antibody (anti-Id), designated as B1/1, was generated against a monoclonal antibody (MoAb 91) specific for Ryegrass pollen allergen Lol p IV. This anti-Id recognized an idiotope (Id) that was also present on other monoclonal antibodies with the same specificity as MoAb 91. Observations that (i) the anti-Id inhibited the binding of MoAb 91 to Lol p IV and (ii) the Id-anti-Id interaction could be inhibited by Lol p IV indicated that the Id was located within or near the antigen combining site. These properties served to characterize B1/1 as an internal image anti-Id. Evidence that an immune response in different species to Lol p IV elicits the formation of antibodies which express a common Id was provided by the observations that (i) the Id-anti-Id interactions could be inhibited by mouse, human and rabbit antisera to Lol p IV and (ii) the binding of these antisera to Lol p IV could be inhibited by the anti-Id. Interestingly, the internal image anti-Id B1/1 also recognized an Id on a monoclonal antibody which was directed to an epitope of Lol p IV, different from that recognized by MoAb 91.

Anti-actin IgA antibodies in severe coeliac disease.

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Granito, A; Muratori, P; Cassani, F; Pappas, G; Muratori, L; Agostinelli, D; Veronesi, L; Bortolotti, R; Petrolini, N; Bianchi, F B; Volta, U

2004-08-01

Anti-actin IgA antibodies have been found in sera of coeliacs. Our aim was to define the prevalence and clinical significance of anti-actin IgA in coeliacs before and after gluten withdrawal. One hundred and two biopsy-proven coeliacs, 95 disease controls and 50 blood donors were studied. Anti-actin IgA were evaluated by different methods: (a) antimicrofilament positivity on HEp-2 cells and on cultured fibroblasts by immunofluorescence; (b) anti-actin positivity by enzyme-linked immuosorbent assay (ELISA); and (c) presence of the tubular/glomerular pattern of anti-smooth muscle antibodies on rat kidney sections by immunofluorescence. Antimicrofilament IgA were present in 27% of coeliacs and in none of the controls. Antimicrofilament antibodies were found in 25 of 54 (46%) coeliacs with severe villous atrophy and in three of 48 (6%) with mild damage (P < 0.0001). In the 20 patients tested, antimicrofilaments IgA disappeared after gluten withdrawal in accordance with histological recovery. Our study shows a significant correlation between antimicrofilament IgA and the severity of intestinal damage in untreated coeliacs. The disappearance of antimicrofilament IgA after gluten withdrawal predicts the normalization of intestinal mucosa and could be considered a useful tool in the follow-up of severe coeliac disease.

Microangiopathic antiphospholipid antibody syndrome due to anti-phosphatidylserine/prothrombin complex IgM antibody.

Science.gov (United States)

Senda, Yumi; Ohta, Kazuhide; Yokoyama, Tadafumi; Shimizu, Masaki; Furuichi, Kengo; Wada, Takashi; Yachie, Akihiro

2017-03-01

Herein we describe a case of microangiopathic antiphospholipid syndrome (MAPS) due to anti-phosphatidylserine/prothrombin complex (aPS/PT) IgM antibody successfully treated with rituximab. A significant correlation was observed between the clinical course and the aPS/PT IgM antibody titer, which can rise earlier before the appearance of clinical symptoms. Rituximab can be safely and effectively used for MAPS. Although detection of only aPS/PT IgM antibody is rare, aPS/PT IgM antibody might be associated with the pathogenesis of MAPS and might be a useful marker of disease activity. © 2017 Japan Pediatric Society.

Anti-cyclic Citrullinated Peptide Antibody (Anti-CCP and Diagnostic Value for Rheumatoid Arthritis

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Mehmet Agilli

2014-02-01

Full Text Available Rheumatoid arthritis (RA is an inflammatory multisystem disease of unknown etiology characterized by chronic destructive synovitis. It and #8217;s prevalence is about 1% all over the world. Serologic markers are also important beside some clinical situations upon RA diagnosis. Today, the most commonly used laboratory test is rheumatoid factor (RF in patients with suspected RA. RF is sensitive but not a specific biomarker for diagnosing RA. Early diagnosis of RA is essential to prevent of progressive joint damage. In recent years, anticyclic citrullinated peptide/protein antibody (anti-CCP attracts the attention as a remarkable biomarker for early diagnosis. Anti-CCP which is a family of anti-citrullinated protein antibodies (ACPA family, showed quite satisfactory specificity in the diagnosis of RA. Due to the prescence of ACPA was included to 2010 RA diagnostic criteria, in a manner of speaking, importance of anti-CCP was registered. [TAF Prev Med Bull 2014; 13(1.000: 83-88

[The diagnostic value of anti-CMV and anti-HPV-B19 antiviral antibodies in studies on causes of recurrent abortions].

Science.gov (United States)

Szkaradkiewicz, A; Pieta, P; Tułecka, T; Breborowicz, G; Słomko, Z; Strzyzowski, P

1997-04-01

Presence of serum anti-cytomegalovirus (CMV) and anti-parvovirus B19 (HPV-B19) antibodies was studied in 11 women within the first day after consecutive spontaneous abortion in the second trimester of pregnancy and in the control group, consisting of 15 women in the second trimester of a normal pregnancy. Most of studied women manifested presence of serum IgG class anti-CMV antibodies (IgG-anti-CMV) and levels of the antibodies proved significantly higher in women following spontaneous abortions. The patients frequently demonstrated in parallel presence of serum IgG class anti-HPV-B19 antibodies. In one patient a generalised nonimmunological hydrops fetalis was disclosed and her serum contained IgM and IgG class antibodies against CMV as well as against HPV-B19. The results suggest that in majority of the studied women the spontaneous abortion might have resulted from fetal infection due to reactivation of chronic CMV infection in the course of pregnancy.

21 CFR 866.5785 - Anti-Saccharomyces cerevisiae (S. cerevisiae) antibody (ASCA) test systems.

Science.gov (United States)

2010-04-01

...) antibody (ASCA) test systems. 866.5785 Section 866.5785 Food and Drugs FOOD AND DRUG ADMINISTRATION... Immunological Test Systems § 866.5785 Anti-Saccharomyces cerevisiae (S. cerevisiae) antibody (ASCA) test systems. (a) Identification. The Anti-Saccharomyces cerevisiae (S. cerevisiae) antibody (ASCA) test system is...

[Anti-FGF23 antibody therapy for patients with tumor-induced osteomalacia].

Science.gov (United States)

Kinoshita, Yuka; Fukumoto, Seiji

2014-08-01

Tumor-induced osteomalacia (TIO) is a disease caused by fibroblast growth factor 23 (FGF23) secreted from the causative tumor. This disease is cured by complete surgical removal of the tumor. However, there are several difficult cases in which the responsible tumors cannot be found, are incompletely removed, or relapse after the surgery. Anti-FGF23 antibody is being studied as a novel therapy for FGF23-related hypophosphatemic diseases. The efficacy of anti-FGF23 antibodies were confirmed using a murine model of X-linked hypophosphatemic rickets (XLHR) , which is the most common heritable form of FGF23-related hypophosphatemic disease. In addition, results of phase I study of single injection of humanized anti-FGF23 antibody for adult patients with XLHR were recently published and the safety and effectiveness of this antibody was shown. This antibody therapy may be useful for patients with TIO with similar pathogenesis to that of XLHR.

Clinical utility of anti-p53 auto-antibody: systematic review and focus on colorectal cancer.

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Suppiah, Aravind; Greenman, John

2013-08-07

Mutation of the p53 gene is a key event in the carcinogenesis of many different types of tumours. These can occur throughout the length of the p53 gene. Anti-p53 auto-antibodies are commonly produced in response to these p53 mutations. This review firstly describes the various mechanisms of p53 dysfunction and their association with subsequent carcinogenesis. Following this, the mechanisms of induction of anti-p53 auto-antibody production are shown, with various hypotheses for the discrepancies between the presence of p53 mutation and the presence/absence of anti-p53 auto-antibodies. A systematic review was performed with a descriptive summary of key findings of each anti-p53 auto-antibody study in all cancers published in the last 30 years. Using this, the cumulative frequency of anti-p53 auto-antibody in each cancer type is calculated and then compared with the incidence of p53 mutation in each cancer to provide the largest sample calculation and correlation between mutation and anti-p53 auto-antibody published to date. Finally, the review focuses on the data of anti-p53 auto-antibody in colorectal cancer studies, and discusses future strategies including the potentially promising role using anti-p53 auto-antibody presence in screening and surveillance.

Prevalence of Anti-Thyroid Antibodies in Patients with Primary ...

African Journals Online (AJOL)

Objective: To determine prevalence of thyroid antimicrosomal and antithyroglobulin antibodies among patients with primary thyroid disorders. Design: Descriptive cross-sectional study. Setting: Kenyatta National Hospital, July 2003 to August 2004. Results: Antimicrosomal antibodies (anti-TPOAbs) were detected in 51.4% ...

Anti-neutrophil cytoplasmic antibodies in rheumatoid arthritis: two case reports and review of literature

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Spoerl David

2012-12-01

Full Text Available Abstract Background Anti-neutrophil cytoplasmic antibodies are typically detected in anti-neutrophil cytoplasmic antibody associated vasculitis, but are also present in a number of chronic inflammatory non-vasculitic conditions like rheumatoid arthritis. Rare cases of granulomatosis with polyangiitis (formerly known as Wegener’s granulomatosis, a vasculitic disorder frequently associated with the presence of anti-neutrophil cytoplasmic antibodies in patients with rheumatoid arthritis have been described in literature. Case presentation We report two middle-aged female patients with rheumatoid arthritis who developed anti-neutrophil cytoplasmic antibodies and symptoms reminiscent of granulomatosis with polyangiitis. Despite the lack of antibodies specific for proteinase 3 and the absence of a classical histology, we report a probable case of granulomatosis with polyangiitis in the first patient, and consider rheumatoid vasculitis in the second patient. Conclusion Taken together with previous reports, these cases highlight that anti-neutrophil cytoplasmic antibodies have to be evaluated very carefully in patients with rheumatoid arthritis. In this context, anti-neutrophil cytoplasmic antibodies detected by indirect immunofluorescence appear to have a low diagnostic value for granulomatosis with polyangiitis. Instead they may have prognostic value for assessing the course of rheumatoid arthritis.

Lymphocyte antibody-dependent cytotoxicity test for evaluation of clinical role of monoclonal anti-D-antibodies for prevention of rhesus sensitization.

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Olovnikova, N I; Belkina, E V; Nikolaeva, T L; Miterev, G Yu; Chertkov, I L

2006-01-01

Monoclonal antibodies to D antigen were studied in the reaction of antibody-dependent cytotoxicity for evaluation of the possibility of using these antibodies for preventing rhesus sensitization. High hemolytic activity of four anti-D-monoclonal antibodies in the antibody-dependent cytotoxicity test, mediated by their interaction with FcgammaRI, and the capacity to accelerate elimination of D+ erythrocytes from circulation did not provide the immunosuppressive effect. It was hypothesized that monoclonal antibodies for prevention of rhesus sensitization should interact with FcgammaRIII on lymphocytes. These monoclonal antibodies are extremely rare: only 4 of 125 studied antibodies mediated hemolysis in the antibody-dependent cytotoxicity test with lymphocytes, while all polyclonal anti-D-preparations exhibited this activity.

Anti-idiotypic antibodies that protect cells against the action of diphtheria toxin

International Nuclear Information System (INIS)

Rolf, J.M.; Gaudin, H.M.; Tirrell, S.M.; MacDonald, A.B.; Eidels, L.

1989-01-01

An anti-idiotypic serum prepared against the combining site (idiotype) of specific anti-diphtheria toxoid antibodies was characterized with respect to its interaction with highly diphtheria toxin-sensitive Vero cells. Although the anti-idiotypic serum protected Vero cells against the cytotoxic action of diphtheria toxin, it did not prevent the binding of 125 I-labeled diphtheria toxin to the cells but did inhibit the internalization and degradation of 125 I-labeled toxin. This anti-idiotypic serum immunoprecipitated a cell-surface protein from radiolabeled Vero cells with an apparent Mr of approximately 15,000. These results are consistent with the hypothesis that the anti-idiotypic serum contains antibodies that carry an internal image of an internalization site on the toxin and that a cell-surface protein involved in toxin internalization possesses a complementary site recognized by both the toxin and the anti-idiotypic antibodies

Activity, specificity, and titer of naturally occurring canine anti-DEA 7 antibodies.

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Spada, Eva; Proverbio, Daniela; Baggiani, Luciana; Canzi, Ilaria; Perego, Roberta

2016-11-01

The reported prevalence of naturally occurring anti-dog erythrocyte antigen (DEA) 7 antibodies in DEA 7-negative dogs is as high as 50%. Characterization of these antibodies may better define their importance in canine transfusion medicine. We determined in vitro activity, specificity, and titer of anti-DEA 7 antibodies in DEA 7-negative dogs. Plasma samples from 317 DEA 7-negative dogs were cross-matched with DEA 7-positive red blood cells (RBCs) using gel column technology. Agglutination occurred with DEA 7-positive RBCs but not with DEA 7-negative RBCs in 73 samples (23%), which were hence classified as containing anti-DEA 7 antibodies. These samples were evaluated for hemolytic and agglutinating activity, strength of agglutination, and antibody specificity and titers. All samples showed agglutination but none showed hemolysis. Gel agglutination was graded as 1+ for 20 samples (27%), 2+ for 49 samples (67%), 3+ for 4 samples (6%); no samples were graded 4+. The agglutination titer was DEA 7 antibodies were found in 23% of DEA 7-negative dogs. The presence of naturally occurring anti-DEA 7 antibodies suggests that cross-matching of canine blood recipients is advisable, even at first transfusion, to minimize delayed transfusion reactions. © 2016 The Author(s).

Antibody to liver cytosol (anti-LC1) in patients with autoimmune chronic active hepatitis type 2.

Science.gov (United States)

Martini, E; Abuaf, N; Cavalli, F; Durand, V; Johanet, C; Homberg, J C

1988-01-01

A new autoantibody was detected by immunoprecipitation in the serum of 21 patients with chronic active hepatitis. The antibody reacted against a soluble cytosolic antigen in liver. The antibody was organ specific but not species specific and was therefore called anti-liver cytosol antibody Type 1 (anti-LC1). In seven of 21 cases, no other autoantibody was found; the remaining 14 cases had anti-liver/kidney microsome antibody Type 1 (anti-LKM1). With indirect immunofluorescence, a distinctive staining pattern was observed with the seven sera with anti-LC1 and without anti-LKM1. The antibody stained the cytoplasm of hepatocytes from four different animal species and spared the cellular layer around the central veins of mouse and rat liver that we have called juxtavenous hepatocytes. The immunofluorescence pattern disappeared after absorption of sera by a liver cytosol fraction. The 14 sera with both antibodies displayed anti-LC1 immunofluorescent pattern after absorption of anti-LKM1 by the liver microsomal fraction. The anti-LC1 was found in the serum only in patients with chronic active hepatitis of unknown cause. Anti-LC1 antibody was not found in sera from 100 patients with chronic active hepatitis associated with anti-actin antibody classic chronic active hepatitis Type 1, 100 patients with primary biliary cirrhosis, 157 patients with drug-induced hepatitis and a large number of patients with liver and nonliver diseases. This new antibody was considered a second marker of chronic active hepatitis associated with anti-LKM1 (anti-LKM1 chronic active hepatitis) or autoimmune chronic active hepatitis Type 2.

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

Anti-DNA antibody in serum measured by radioimmunoassay (Farr technique)

Energy Technology Data Exchange (ETDEWEB)

Manthorpe, R; Palit, J; Bendixen, G [Rigshospitalet, Copenhagen (Denmark)

1978-01-01

The anti DNA antibody determination in serum is increasingly used because it supports the diagnosis of systemic lupus erythematosus (SLE) with high selectivity. The present work evaluates several of the technical variables of the Farr radioimmunoassay for anti-DNA antibody determination and describes a recommendable procedure. The most important sources of error are emphasized and the range for normal blood donors and a group of hospital patients without SLE is given.

Anti-DNA antibody in serum measured by radioimmunoassay (Farr technique)

International Nuclear Information System (INIS)

Manthorpe, R.; Palit, J.; Bendixen, G.

1978-01-01

Anti-DNA antibody determination in serums is increasingly used because it supports the diagnosis of systemic lupres erythematosus (SLE) with high selectivity. The present work evaluates several of the technical variables of the Farr radioimmunoassay for anti-DNA antibody determination and describes a recommendable procedure, emphasizes the most important sources of error and gives the range of normal blood donors and a group of hospital patients without SLE. (author)

Development of new versions of anti-human CD34 monoclonal antibodies with potentially reduced immunogenicity

International Nuclear Information System (INIS)

Qian Weizhu; Wang Ling; Li Bohua; Wang Hao; Hou Sheng; Hong Xueyu; Zhang Dapeng; Guo Yajun

2008-01-01

Despite the widespread clinical use of CD34 antibodies for the purification of human hematopoietic stem/progenitor cells, all the current anti-human CD34 monoclonal antibodies (mAbs) are murine, which have the potential to elicit human antimouse antibody (HAMA) immune response. In the present study, we developed three new mouse anti-human CD34 mAbs which, respectively, belonged to class I, class II and class III CD34 epitope antibodies. In an attempt to reduce the immunogenicity of these three murine mAbs, their chimeric antibodies, which consisted of mouse antibody variable regions fused genetically to human antibody constant regions, were constructed and characterized. The anti-CD34 chimeric antibodies were shown to possess affinity and specificity similar to that of their respective parental murine antibodies. Due to the potentially better safety profiles, these chimeric antibodies might become alternatives to mouse anti-CD34 antibodies routinely used for clinical application

Hybrid IgG4/IgG4 Fc antibodies form upon 'Fab-arm' exchange as demonstrated by SDS-PAGE or size-exclusion chromatography

NARCIS (Netherlands)

Rispens, Theo; den Bleker, Tamara H.; Aalberse, Rob C.

2010-01-01

Human IgG4 antibodies are dynamic molecules that in vivo exchange half-molecules to become bispecific antibodies. Here we show that IgG4 antibodies and IgG4 Fc fragments similarly exchange resulting in hybrid antibodies (a single Fab + Fc) with a molecular weight of ca. 100 kDa. These antibodies can

Detection of anti-tetanus toxoid antibody on modified polyacrylonitrile fibers.

Science.gov (United States)

Jain, Swati; Chattopadhyay, Sruti; Jackeray, Richa; Zainul Abid, C K V; Kumar, Manoj; Singh, Harpal

2010-10-15

Accurate determination of concentration of immunoglobulin (IgG) to tetanus toxoid is important in order to evaluate the immunogenicity of tetanus toxoid vaccines, immune competence in individual patients and to measure the prevalence of immunity in populations. Surface modified polyacrylonitrile (PAN) fibers were evaluated as a matrix to develop highly sensitive method for the detection of anti-tetanus antibody in a sandwich ELISA format. In the proposed method tetanus toxoid immobilized on modified PAN fibers was used to detect anti-tetanus antibody (raised in horse hence represented as horse anti-tetanus toxoid or HAT-Ab) with horse raddish peroxidase enzyme conjugated with Rabbit anti-Horse IgG (RAH-HRP) as the label within 2.5h. A sigmoidal pattern for the detection of different concentration of antibody ranging from 1.0 to 0.0001 IU mL(-1) was validated. The immunoassay recorded a very high sensitivity as concentration as low as 0.0005 IU mL(-1) of HAT-Ab was detected. The intra- and inter-assay precision for 3 parallel measurements of 0.01 and for 0.001 IU mL(-1) of antibody varied from 5.4% to 11% and 5.7% to 20% respectively. PAN fibers were also used to qualitatively access the presence of different level of anti-tetanus antibody spiked in human blood. Seroepidemiological studies to measure the immunity against tetanus were conducted with twenty-five human beings belonging to various age groups using modified PAN-ELISA. The sensitivity, specificity and the reproducibility of the developed immunoassay indicate the potential application of modified PAN fibers in the field of immunodiagnostics. Copyright © 2010 Elsevier B.V. All rights reserved.

Anti-idiotypic antibodies that protect cells against the action of diphtheria toxin

Energy Technology Data Exchange (ETDEWEB)

Rolf, J.M.; Gaudin, H.M.; Tirrell, S.M.; MacDonald, A.B.; Eidels, L.

1989-03-01

An anti-idiotypic serum prepared against the combining site (idiotype) of specific anti-diphtheria toxoid antibodies was characterized with respect to its interaction with highly diphtheria toxin-sensitive Vero cells. Although the anti-idiotypic serum protected Vero cells against the cytotoxic action of diphtheria toxin, it did not prevent the binding of /sup 125/I-labeled diphtheria toxin to the cells but did inhibit the internalization and degradation of /sup 125/I-labeled toxin. This anti-idiotypic serum immunoprecipitated a cell-surface protein from radiolabeled Vero cells with an apparent Mr of approximately 15,000. These results are consistent with the hypothesis that the anti-idiotypic serum contains antibodies that carry an internal image of an internalization site on the toxin and that a cell-surface protein involved in toxin internalization possesses a complementary site recognized by both the toxin and the anti-idiotypic antibodies.

Anti-Transglutaminase 6 Antibodies in Children and Young Adults with Cerebral Palsy

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Reidun Stenberg

2014-01-01

Full Text Available Objectives. We have previously reported a high prevalence of gluten-related serological markers (GRSM in children and young adults with cerebral palsy (CP. The majority had no enteropathy to suggest coeliac disease (CD. Antibodies against transglutaminase 6 (anti-TG6 represent a new marker associated with gluten-related neurological dysfunction. The aim of this study was to investigate the prevalence of anti-TG6 antibodies in this group of individuals with an early neurological injury resulting in CP. Materials and Methods. Sera from 96 patients with CP and 36 controls were analysed for IgA/IgG class anti-TG6 by ELISA. Results. Anti-TG6 antibodies were found in 12/96 (13% of patients with CP compared to 2/36 (6% in controls. The tetraplegic subgroup of CP had a significantly higher prevalence of anti-TG6 antibodies 6/17 (35% compared to the other subgroups and controls. There was no correlation of anti-TG6 autoantibodies with seropositivity to food proteins including gliadin. Conclusions. An early brain insult and associated inflammation may predispose to future development of TG6 autoimmunity.

Clinical significance of changes of expression of anti-dsDNA antibody in serum in patients with SLE

International Nuclear Information System (INIS)

Chen Xingguo; Zhang Xiaoli; Liu Chunyan; Cao Jiwei; Du Tongxing; Wang Zizheng

2008-01-01

Objective: To investigate the significance of anti-dsDNA antibody in diagnosis and treatment of SLE through measurement of changes of serum anti-dsDNA antibody expression in patients with SLE. Methods: Serum anti-dsDNA antibody was detected with radioisotope method in 60 patients with SLE and 33 controls (consisted of patients with other collagen diseases including Sjogren syndrome, systemic sclerosis, rheumatoid arthritis, polymyositis, mixed connective tissue disease, ankylosing spondylitis). Clinical manifestation and laboratory findings in the SLE patients were studied in detail. Results: (1) Serum anti-dsDNA antibody was positive in 39 of the 60 SLE patients with only two false positive cases in the 33 controls: a sensitivity of 65% and specificity of 93. 3%. (2) In SLE patients, positivity of anti-dsDNA antibody was not correlated with positivity of anti-Sm antibody (P>0.05), but was correlated with positivity of anti-SSA antibody (P<0.05). (3) Incidences of alopecia, skin rashes, oral mucosal ulcer, proteinuria were significantly higher in SLE patients with positive anti-dsDNA antibody than those in SLE patients with negative anti-dsDNA antibody (P<0.05). (4) Incidences of leukopenia and thrombocytopenia were also significantly higher in SLE patients with positive anti-dsDNA antibody (P<0.05). Conclusion: Anti-dsDNA antibody could be taken as a specific marker of SLE and the serum expression were positively correlated with the activity and severity of the disease. (authors)

Anti-coagulation effect of Fc fragment against anti-β2-GP1 antibodies in mouse models with APS.

Science.gov (United States)

Xie, Weidong; Zhang, Yaou; Bu, Cunya; Sun, Shijing; Hu, Shaoliang; Cai, Guoping

2011-01-01

Anti-beta (2)-glycoprotein I (anti-β2-GP1) is one of the important pathogenesis factors responsible for thrombosis formation in patients with antiphospholipid syndrome (APS). Administration of intravenous immunoglobulin (IVIg) is a common method used to inhibit the abnormal antibody levels and decrease the mortality of APS in emergency situations. We hypothesize that the Fc fragment of IgG is the molecular structure responsible for these effects. The present study investigates the beneficial effects of both recombinant and natural human Fc fragments of heterogeneous IgG against human anti-β2-GP1 antibodies in mouse models with APS. Results showed that both recombinant and natural human Fc fragments moderately but significantly decreased the levels of serum anti-β2-GP1 antibodies and had anti-coagulation effects in human β2-GP1-immunized mice. Furthermore, both recombinant and natural human Fc fragments inhibited thrombosis formation and decreased mortality in mouse models infused intravenously with human anti-β2GP1 antibodies from patients with APS. Findings suggest that the Fc fragment might be one of the active structural units of heterogeneous IgG. Thus, recombinant human Fc fragment administration may be a useful treatment for individuals with APS. Copyright © 2010 Elsevier B.V. All rights reserved.

Membranous Nephropathy and Anti-Podocytes Antibodies: Implications for the Diagnostic Workup and Disease Management.

Science.gov (United States)

Pozdzik, Agnieszka; Brochériou, Isabelle; David, Cristina; Touzani, Fahd; Goujon, Jean Michel; Wissing, Karl Martin

2018-01-01

The discovery of circulating antibodies specific for native podocyte antigens has transformed the diagnostic workup and greatly improved management of idiopathic membranous nephropathy (iMN). In addition, their identification has clearly characterized iMN as a largely autoimmune disorder. Anti-PLA2R1 antibodies are detected in approximately 70% to 80% and anti-THSD7A antibodies in only 2% of adult patients with iMN. The presence of anti-THSD7A antibodies is associated with increased risk of malignancy. The assessment of PLA2R1 and THSD7A antigen expression in glomerular immune deposits has a better sensitivity than measurement of the corresponding autoantibodies. Therefore, in the presence of circulating anti-podocytes autoantibodies and/or enhanced expression of PLA2R1 and THSD7A antigens MN should be considered as primary MN (pMN). Anti-PLA2R1 or anti-THSD7A autoantibodies have been proposed as biomarkers of autoimmune disease activity and their blood levels should be regularly monitored in pMN to evaluate disease activity and predict outcomes. We propose a revised clinical workup flow for patients with MN that recommends assessment of kidney biopsy for PLA2R1 and THSD7A antigen expression, screening for circulating anti-podocytes antibodies, and assessment for secondary causes, especially cancer, in patients with THSD7A antibodies. Persistence of anti-podocyte antibodies for 6 months or their increase in association with nephrotic proteinuria should lead to the introduction of immunosuppressive therapies. Recent data have reported the efficacy and safety of new specific therapies targeting B cells (anti-CD20 antibodies, inhibitors of proteasome) in pMN which should lead to an update of currently outdated treatment guidelines.

Miller-Fisher Syndrome: Are Anti-GAD Antibodies Implicated in Its Pathophysiology?

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Ioannis E. Dagklis

2016-01-01

Full Text Available Miller-Fisher syndrome (MFS is considered as a variant of the Guillain-Barre syndrome (GBS and its characteristic clinical features are ophthalmoplegia, ataxia, and areflexia. Typically, it is associated with anti-GQ1b antibodies; however, a significant percentage (>10% of these patients are seronegative. Here, we report a 67-year-old female patient who presented with the typical clinical features of MFS. Workup revealed antibodies against glutamic acid decarboxylase (GAD in relatively high titers while GQ1b antibodies were negative. Neurological improvement was observed after intravenous gamma globulin and follow-up examinations showed a continuous clinical amelioration with simultaneous decline of anti-GAD levels which finally returned to normal values. This case indicates that anti-GAD antibodies may be associated with a broader clinical spectrum and future studies in GQ1b-seronegative patients could determine ultimately their clinical and pathogenetic significance in this syndrome.

Production of human anti-HLA monoclonal antibodies

Energy Technology Data Exchange (ETDEWEB)

Walker, M.C.; Mercier, F.; Roger, J.; Varin, M.

1986-03-01

Only 40% of the several hundred anti-HLA murine monoclonal antibodies (MAbs) that have been made detect HLA-A,B,C or DR specificities previously defined by human alloantisera, the range of recognized specificities is very narrow, and few of the MAbs have proven useful as tissue typing reagents. In hopes of obtaining HLA typing reagents, the authors are developing a protocol for the production of human anti-HLA MAbs from HLA-antigen (Ag) immunized peripheral blood B cells of volunteering renal patients, immunized to one or more HLA Ags through therapeutic blood transfusions. A simple enrichment of the donor B cells has not been sufficient for anti-HLA MAb production, the authors are currently delineating the conditions necessary for increasing the number of HLA-specific donor B cells by in vitro stimulation with cells expressing the HLA Ag to which the B cell donor is immunized. For the production of MAbs, the stimulated B cells are transformed with Epstein-Barr virus and subsequently fused with KR-4 lymphoblastoid cells. Hybridomas are selected by HAT and Ouabain. Supernatants are screened for anti-HLA activity against lymphocyte targets expressing the original immunizing HLA Ag by complement mediated /sup 51/Cr release assay. Antibody specificity is determined by the complement-dependent microcytotoxicity test used for HLA typing.

Induction of CD4 suppressor T cells with anti-Leu-8 antibody

International Nuclear Information System (INIS)

Kanof, M.E.; Strober, W.; James, S.P.

1987-01-01

To characterize the conditions under which CD4 T cells suppress polyclonal immunoglobulin synthesis, we investigated the capacity of CD4 T cells that coexpress the surface antigen recognized by the monoclonal antibody anti-Leu-8 to mediate suppression. In an in vitro system devoid of CD8 T cells, CD4, Leu-8+ T cells suppressed pokeweed mitogen-induced immunoglobulin synthesis. Similarly, suppressor function was induced in unfractionated CD4 T cell populations after incubation with anti-Leu-8 antibody under cross-linking conditions. This induction of suppressor function by anti-Leu-8 antibody was not due to expansion of the CD4, Leu-8+ T cell population because CD4 T cells did not proliferate in response to anti-Leu-8 antibody. However, CD4, Leu-8+ T cell-mediated suppression was radiosensitive. Finally, CD4, Leu-8+ T cells do not inhibit immunoglobulin synthesis when T cell lymphokines were used in place of helper CD4 T cells (CD4, Leu-8- T cells), suggesting that CD4 T cell-mediated suppression occurs at the T cell level. We conclude that CD4 T cells can be induced to suppress immunoglobulin synthesis by modulation of the membrane antigen recognized by anti-Leu-8 antibody

Immediate and Catastrophic Antibody-Mediated Rejection in a Lung Transplant Recipient With Anti-Angiotensin II Receptor Type 1 and Anti-Endothelin-1 Receptor Type A Antibodies.

Science.gov (United States)

Cozzi, E; Calabrese, F; Schiavon, M; Feltracco, P; Seveso, M; Carollo, C; Loy, M; Cardillo, M; Rea, F

2017-02-01

Preexisting donor-specific anti-HLA antibodies (DSAs) have been associated with reduced survival of lung allografts. However, antibodies with specificities other than HLA may have a detrimental role on the lung transplant outcome. A young man with cystic fibrosis underwent lung transplantation with organs from a suitable deceased donor. At the time of transplantation, there were no anti-HLA DSAs. During surgery, the patient developed a severe and intractable pulmonary hypertension associated with right ventriular dysfunction, which required arteriovenous extracorporeal membrane oxygenation. After a brief period of clinical improvement, a rapid deterioration in hemodynamics led to the patient's death on postoperative day 5. Postmortem studies showed that lung specimens taken at the end of surgery were compatible with antibody-mediated rejection (AMR), while terminal samples evidenced diffuse capillaritis, blood extravasation, edema, and microthrombi, with foci of acute cellular rejection (A3). Immunological investigations demonstrated the presence of preexisting antibodies against the endothelin-1 receptor type A (ET A R) and the angiotensin II receptor type 1 (AT 1 R), two of the most potent vasoconstrictors reported to date, whose levels slightly rose after transplantation. These data suggest that preexisting anti-ET A R and anti-AT 1 R antibodies may have contributed to the onset of AMR and to the catastrophic clinical course of this patient. © Copyright 2016 The American Society of Transplantation and the American Society of Transplant Surgeons.

Comparison of Two Assays to Determine Anti-Citrullinated Peptide Antibodies in Rheumatoid Arthritis in relation to Other Chronic Inflammatory Rheumatic Diseases: Assaying Anti-Modified Citrullinated Vimentin Antibodies Adds Value to Second-Generation Anti-Citrullinated Cyclic Peptides Testing

Directory of Open Access Journals (Sweden)

Miriam Lizette Díaz-Toscano

2014-01-01

Full Text Available Determination of anti-citrullinated peptide antibodies (ACPA plays a relevant role in the diagnosis of rheumatoid arthritis (RA. To date, it is still unclear if the use of several tests for these autoantibodies in the same patient offers additional value as compared to performing only one test. Therefore, we evaluated the performance of using two assays for ACPA: second-generation anti-citrullinated cyclic peptides antibodies (anti-CCP2 and anti-mutated citrullinated vimentin (anti-MCV antibodies for the diagnosis of RA. We compared three groups: RA (n=142, chronic inflammatory disease (CIRD, n=86, and clinically healthy subjects (CHS, n=56 to evaluate sensitivity, specificity, predictive values, and likelihood ratios (LR of these two assays for the presence of RA. A lower frequency of positivity for anti-CCP2 was found in RA (66.2% as compared with anti-MCV (81.0%. When comparing RA versus other CIRD, sensitivity increased when both assays were performed. This strategy of testing both assays had high specificity and LR+. We conclude that adding the assay of anti-MCV antibodies to the determination of anti-CCP2 increases the sensitivity for detecting seropositive RA. Therefore, we propose the use of both assays in the initial screening of RA in longitudinal studies, including early onset of undifferentiated arthritis.

Expression of recombinant Antibodies

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André eFrenzel

2013-07-01

Full Text Available Recombinant antibodies are highly specific detection probes in research, diagnostics and have emerged over the last two decades as the fastest growing class of therapeutic proteins. Antibody generation has been dramatically accelerated by in vitro selection systems, particularly phage display. An increasing variety of recombinant production systems have been developed, ranging from Gram-negative and positive bacteria, yeasts and filamentous fungi, insect cell lines, mammalian cells to transgenic plants and animals. Currently, almost all therapeutic antibodies are still produced in mammalian cell lines in order to reduce the risk of immunogenicity due to altered, non-human glycosylation patterns. However, recent developments of glycosylation-engineered yeast, insect cell lines and transgenic plants are promising to obtain antibodies with human-like post-translational modifications. Furthermore, smaller antibody fragments including bispecific antibodies without any glycosylation are successfully produced in bacteria and have advanced to clinical testing. The first therapeutic antibody products from a non-mammalian source can be expected in coming next years. In this review, we focus on current antibody production systems including their usability for different applications.

Emerging Technologies and Generic Assays for the Detection of Anti-Drug Antibodies

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Michael A. Partridge

2016-01-01

Full Text Available Anti-drug antibodies induced by biologic therapeutics often impact drug pharmacokinetics, pharmacodynamics response, clinical efficacy, and patient safety. It is critical to assess the immunogenicity risk of potential biotherapeutics in producing neutralizing and nonneutralizing anti-drug antibodies, especially in clinical phases of drug development. Different assay methodologies have been used to detect all anti-drug antibodies, including ELISA, radioimmunoassay, surface plasmon resonance, and electrochemiluminescence-based technologies. The most commonly used method is a bridging assay, performed in an ELISA or on the Meso Scale Discovery platform. In this report, we aim to review the emerging new assay technologies that can complement or address challenges associated with the bridging assay format in screening and confirmation of ADAs. We also summarize generic anti-drug antibody assays that do not require drug-specific reagents for nonclinical studies. These generic assays significantly reduce assay development efforts and, therefore, shorten the assay readiness timeline.

Anti-tau antibody administration increases plasma tau in transgenic mice and patients with tauopathy

Science.gov (United States)

Yanamandra, Kiran; Patel, Tirth K.; Jiang, Hong; Schindler, Suzanne; Ulrich, Jason D.; Boxer, Adam L.; Miller, Bruce L.; Kerwin, Diana R.; Gallardo, Gilbert; Stewart, Floy; Finn, Mary Beth; Cairns, Nigel J.; Verghese, Philip B.; Fogelman, Ilana; West, Tim; Braunstein, Joel; Robinson, Grace; Keyser, Jennifer; Roh, Joseph; Knapik, Stephanie S.; Hu, Yan; Holtzman, David M.

2017-01-01

Tauopathies are a group of disorders in which the cytosolic protein tau aggregates and accumulates in cells within the brain, resulting in neurodegeneration. A promising treatment being explored for tauopathies is passive immunization with anti-tau antibodies. We previously found that administration of an anti-tau antibody to human tau transgenic mice increased the concentration of plasma tau. We further explored the effects of administering an anti-tau antibody on plasma tau. After peripheral administration of an anti-tau antibody to human patients with tauopathy and to mice expressing human tau in the central nervous system, there was a dose-dependent increase in plasma tau. In mouse plasma, we found that tau had a short half-life of 8 min that increased to more than 3 hours after administration of anti-tau antibody. As tau transgenic mice accumulated insoluble tau in the brain, brain soluble and interstitial fluid tau decreased. Administration of anti-tau antibody to tau transgenic mice that had decreased brain soluble tau and interstitial fluid tau resulted in an increase in plasma tau, but this increase was less than that observed in tau transgenic mice without these brain changes. Tau transgenic mice subjected to acute neuronal injury using 3-nitropropionic acid showed increased interstitial fluid tau and plasma tau. These data suggest that peripheral administration of an anti-tau antibody results in increased plasma tau, which correlates with the concentration of extracellular and soluble tau in the brain. PMID:28424326

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.

Balanced secretion of anti-CEA x anti-CD3 diabody chains using the 2A self-cleaving peptide maximizes diabody assembly and tumor-specific cytotoxicity

DEFF Research Database (Denmark)

Mølgaard, Kasper; Compte, Marta; Alanes, Natalia Nuñez del Prado

2017-01-01

Adoptive transfer of genetically engineered human cells secreting bispecific T cell engagers has shown encouraging therapeutic effects in preclinical models of cancer. However, reducing the toxicity and improving the effectiveness of this emerging immunotherapeutic strategy will be critical to it...

Prognostic significance of anti-p53 and anti-KRas circulating antibodies in esophageal cancer patients treated with chemoradiotherapy

International Nuclear Information System (INIS)

Blanchard, Pierre; Quero, Laurent; Pacault, Vincent; Schlageter, Marie-Helene; Baruch-Hennequin, Valerie; Hennequin, Christophe

2012-01-01

P53 mutations are an adverse prognostic factor in esophageal cancer. P53 and KRas mutations are involved in chemo-radioresistance. Circulating anti-p53 or anti-KRas antibodies are associated with gene mutations. We studied whether anti-p53 or anti-KRas auto-antibodies were prognostic factors for response to chemoradiotherapy (CRT) or survival in esophageal carcinoma. Serum p53 and KRas antibodies (abs) were measured using an ELISA method in 97 consecutive patients treated at Saint Louis University Hospital between 1999 and 2002 with CRT for esophageal carcinoma (squamous cell carcinoma (SCCE) 57 patients, adenocarcinoma (ACE) 27 patients). Patient and tumor characteristics, response to treatment and the follow-up status of 84 patients were retrospectively collected. The association between antibodies and patient characteristics was studied. Univariate and multivariate survival analyses were conducted. Twenty-four patients (28%) had anti-p53 abs. Abs were found predominantly in SCCE (p = 0.003). Anti-p53 abs were associated with a shorter overall survival in the univariate analysis (HR 1.8 [1.03-2.9], p = 0.04). In the multivariate analysis, independent prognostic factors for overall and progression-free survival were an objective response to CRT, the CRT strategy (alone or combined with surgery [preoperative]) and anti-p53 abs. None of the long-term survivors had p53 abs. KRas abs were found in 19 patients (23%, no difference according to the histological type). There was no significant association between anti-KRas abs and survival neither in the univariate nor in the multivariate analysis. Neither anti-p53 nor anti-KRas abs were associated with response to CRT. Anti-p53 abs are an independent prognostic factor for esophageal cancer patients treated with CRT. Individualized therapeutic approaches should be evaluated in this population

Prognostic significance of anti-p53 and anti-KRas circulating antibodies in esophageal cancer patients treated with chemoradiotherapy.

Science.gov (United States)

Blanchard, Pierre; Quero, Laurent; Pacault, Vincent; Schlageter, Marie-Helene; Baruch-Hennequin, Valerie; Hennequin, Christophe

2012-03-26

P53 mutations are an adverse prognostic factor in esophageal cancer. P53 and KRas mutations are involved in chemo-radioresistance. Circulating anti-p53 or anti-KRas antibodies are associated with gene mutations. We studied whether anti-p53 or anti-KRas auto-antibodies were prognostic factors for response to chemoradiotherapy (CRT) or survival in esophageal carcinoma. Serum p53 and KRas antibodies (abs) were measured using an ELISA method in 97 consecutive patients treated at Saint Louis University Hospital between 1999 and 2002 with CRT for esophageal carcinoma (squamous cell carcinoma (SCCE) 57 patients, adenocarcinoma (ACE) 27 patients). Patient and tumor characteristics, response to treatment and the follow-up status of 84 patients were retrospectively collected. The association between antibodies and patient characteristics was studied. Univariate and multivariate survival analyses were conducted. Twenty-four patients (28%) had anti-p53 abs. Abs were found predominantly in SCCE (p = 0.003). Anti-p53 abs were associated with a shorter overall survival in the univariate analysis (HR 1.8 [1.03-2.9], p = 0.04). In the multivariate analysis, independent prognostic factors for overall and progression-free survival were an objective response to CRT, the CRT strategy (alone or combined with surgery [preoperative]) and anti-p53 abs. None of the long-term survivors had p53 abs. KRas abs were found in 19 patients (23%, no difference according to the histological type). There was no significant association between anti-KRas abs and survival neither in the univariate nor in the multivariate analysis. Neither anti-p53 nor anti-KRas abs were associated with response to CRT. Anti-p53 abs are an independent prognostic factor for esophageal cancer patients treated with CRT. Individualized therapeutic approaches should be evaluated in this population.

Prognostic significance of anti-p53 and anti-KRas circulating antibodies in esophageal cancer patients treated with chemoradiotherapy

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Blanchard Pierre

2012-03-01

Full Text Available Abstract Background P53 mutations are an adverse prognostic factor in esophageal cancer. P53 and KRas mutations are involved in chemo-radioresistance. Circulating anti-p53 or anti-KRas antibodies are associated with gene mutations. We studied whether anti-p53 or anti-KRas auto-antibodies were prognostic factors for response to chemoradiotherapy (CRT or survival in esophageal carcinoma. Methods Serum p53 and KRas antibodies (abs were measured using an ELISA method in 97 consecutive patients treated at Saint Louis University Hospital between 1999 and 2002 with CRT for esophageal carcinoma (squamous cell carcinoma (SCCE 57 patients, adenocarcinoma (ACE 27 patients. Patient and tumor characteristics, response to treatment and the follow-up status of 84 patients were retrospectively collected. The association between antibodies and patient characteristics was studied. Univariate and multivariate survival analyses were conducted. Results Twenty-four patients (28% had anti-p53 abs. Abs were found predominantly in SCCE (p = 0.003. Anti-p53 abs were associated with a shorter overall survival in the univariate analysis (HR 1.8 [1.03-2.9], p = 0.04. In the multivariate analysis, independent prognostic factors for overall and progression-free survival were an objective response to CRT, the CRT strategy (alone or combined with surgery [preoperative] and anti-p53 abs. None of the long-term survivors had p53 abs. KRas abs were found in 19 patients (23%, no difference according to the histological type. There was no significant association between anti-KRas abs and survival neither in the univariate nor in the multivariate analysis. Neither anti-p53 nor anti-KRas abs were associated with response to CRT. Conclusions Anti-p53 abs are an independent prognostic factor for esophageal cancer patients treated with CRT. Individualized therapeutic approaches should be evaluated in this population.

Modification of Antibody Function by Mutagenesis.

Science.gov (United States)

Dasch, James R; Dasch, Amy L

2017-09-01

The ability to "fine-tune" recombinant antibodies by mutagenesis separates recombinant antibodies from hybridoma-derived antibodies because the latter are locked with respect to their properties. Recombinant antibodies can be modified to suit the application: Changes in isotype, format (e.g., scFv, Fab, bispecific antibodies), and specificity can be made once the heavy- and light-chain sequences are available. After immunoglobulin heavy and light chains for a particular antibody have been cloned, the binding site-namely, the complementarity determining regions (CDR)-can be manipulated by mutagenesis to obtain antibody variants with improved properties. The method described here is relatively simple, uses commercially available reagents, and is effective. Using the pComb3H vector, a commercial mutagenesis kit, PfuTurbo polymerase (Agilent), and two mutagenic primers, a library of phage with mutagenized heavy and light CDR3 can be obtained. © 2017 Cold Spring Harbor Laboratory Press.

Least speciose among the most speciose: Natural history correlates of monospecific and bispecific genera of Rodentia and Soricomorpha.

Science.gov (United States)

Amori, Giovanni; Bissattini, Alessandra Maria; Gippoliti, Spartaco; Vignoli, Leonardo; Maiorano, Luigi; Luiselli, Luca

2017-11-01

Monospecific and bispecific genera are of special concern as they represent unique phylogenetic/evolutionary trajectories within larger clades. In addition, as phylogenetically older taxa are supposed to be exposed to higher rarity and extinction risk, monospecific and bispecific genera may be intrinsically more prone to extinction risks than multispecies genera, although extinction risks also depend on the ecological and biological strategy of the species. Here, the distribution across biogeographical zones and the levels of threat to 2 speciose orders of mammals (monospecific and bispecific genera of Rodentia and Soricomorpha) are investigated in order to highlight major patterns at the worldwide scale. In Rodentia, 39.7% of the genera (n = 490) were monospecific and 17.9% were bispecific. In Soricomorpha, 44.4% of the total genera (n = 45) were monospecific and 15% were bispecific. There was a positive correlation between the number of monospecific genera and the total number of genera per family. Peaks of monospecific and bispecific genera richness were observed in Neotropical, Oriental and Afrotropical regions in rodents and in the Palearctic region in soricomorphs. Range size was significantly uneven across biogeographic region in rodents (with larger ranges in Nearctic and Oriental regions and smaller ranges in the Australian region), but there was no difference across biogeographic regions in terms of range size in soricomorphs. Most of the monospecific and bispecific genera occurred in forest habitat in both taxa. The frequency distribution of the monospecific and bispecific genera across IUCN categories did not differ significantly from the expected pattern using the total rodent genera and the multispecies genera. © 2017 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

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)

HIV-1 resistance conferred by siRNA cosuppression of CXCR4 and CCR5 coreceptors by a bispecific lentiviral vector

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Akkina Ramesh

2005-01-01

Full Text Available Abstract Background RNA interference (RNAi mediated by small interfering RNAs (siRNAs has proved to be a highly effective gene silencing mechanism with great potential for HIV/AIDS gene therapy. Previous work with siRNAs against cellular coreceptors CXCR4 and CCR5 had shown that down regulation of these surface molecules could prevent HIV-1 entry and confer viral resistance. Since monospecific siRNAs targeting individual coreceptors are inadequate in protecting against both T cell tropic (X4 and monocyte tropic (R5 viral strains simultaneously, bispecific constructs with dual specificity are required. For effective long range therapy, the bispecific constructs need to be stably transduced into HIV-1 target cells via integrating viral vectors. Results To achieve this goal, lentiviral vectors incorporating both CXCR4 and CCR5 siRNAs of short hairpin design were constructed. The CXCR4 siRNA was driven by a U6 promoter whereas the CCR5 siRNA was driven by an H1 promoter. A CMV promoter driven EGFP reporter gene is also incorporated in the bispecific construct. High efficiency transduction into coreceptor expressing Magi and Ghost cell lines with a concomitant down regulation of respective coreceptors was achieved with lentiviral vectors. When the siRNA expressing transduced cells were challenged with X4 and R5 tropic HIV-1, they demonstrated marked viral resistance. HIV-1 resistance was also observed in bispecific lentiviral vector transduced primary PBMCs. Conclusions Both CXCR4 and CCR5 coreceptors could be simultaneously targeted for down regulation by a single combinatorial lentiviral vector incorporating respective anti-coreceptor siRNAs. Stable down regulation of both the coreceptors protects cells against infection by both X4 and R5 tropic HIV-1. Stable down regulation of cellular molecules that aid in HIV-1 infection will be an effective strategy for long range HIV gene therapy.

Naturally occurring anti-glycan antibodies binding to Globo H-expressing cells identify ovarian cancer patients.

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Pochechueva, Tatiana; Alam, Shahidul; Schötzau, Andreas; Chinarev, Alexander; Bovin, Nicolai V; Hacker, Neville F; Jacob, Francis; Heinzelmann-Schwarz, Viola

2017-02-10

Glycosphingolipids are important compounds of the plasma membrane of mammalian cells and a number of them have been associated with malignant transformation and progression, reinforcing tumour aggressiveness and metastasis. Here we investigated the levels of naturally occurring anti-glycan antibodies to Globo H in blood plasma obtained from high-grade serous ovarian cancer patients (SOC) and women without gynaecological malignancies (control) using suspension glycan array technology employing chemically synthesized glycans as antibody targets. We found that anti-human Globo H IgG antibodies were able to significantly discriminate SOC from controls (P anti-Globo H antibodies highly correlated (r = 0.992). The incubation of plasma-derived anti-glycan antibodies with chemically synthesized (presented on fluorescence microspheres) and native Globo H (expressed on Globo H-positive cell lines) revealed strong reactivity of naturally occurring human anti-Globo H antibodies towards its antigen expressed on ovarian cancer cells. Our data demonstrate that human plasma-derived antibodies to Globo H as well as the presence of the antigen might be considered as therapeutic option in ovarian cancer.

New Strategies Using Antibody Combinations to Increase Cancer Treatment Effectiveness

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Isabel Corraliza-Gorjón

2017-12-01

Full Text Available Antibodies have proven their high value in antitumor therapy over the last two decades. They are currently being used as the first-choice to treat some of the most frequent metastatic cancers, like HER2+ breast cancers or colorectal cancers, currently treated with trastuzumab (Herceptin and bevacizumab (Avastin, respectively. The impressive therapeutic success of antibodies inhibiting immune checkpoints has extended the use of therapeutic antibodies to previously unanticipated tumor types. These anti-immune checkpoint antibodies allowed the cure of patients devoid of other therapeutic options, through the recovery of the patient’s own immune response against the tumor. In this review, we describe how the antibody-based therapies will evolve, including the use of antibodies in combinations, their main characteristics, advantages, and how they could contribute to significantly increase the chances of success in cancer therapy. Indeed, novel combinations will consist of mixtures of antibodies against either different epitopes of the same molecule or different targets on the same tumor cell; bispecific or multispecific antibodies able of simultaneously binding tumor cells, immune cells or extracellular molecules; immunomodulatory antibodies; antibody-based molecules, including fusion proteins between a ligand or a receptor domain and the IgG Fab or Fc fragments; autologous or heterologous cells; and different formats of vaccines. Through complementary mechanisms of action, these combinations could contribute to elude the current limitations of a single antibody which recognizes only one particular epitope. These combinations may allow the simultaneous attack of the cancer cells by using the help of the own immune cells and exerting wider therapeutic effects, based on a more specific, fast, and robust response, trying to mimic the action of the immune system.

Frequency of anti-Chlamydia trachomatis antibodies in infertile women referred to Tabriz Al-Zahra hospital

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Mahtab Sattari

2017-08-01

Full Text Available Background: Infertility is one of the major issues in society and its incidence is estimated to be almost 10-15%. Chlamydia trachomatis (C. trachomatis is an important cause of sexually transmitted diseases leading to infertility. Objective: This study was designed to determine the frequency of anti-C. trachomatis antibodies in infertile women at Al-zahra hospital, Tabriz, Iran. Materials and Methods: In this cross-sectional study, the blood samples were collected randomly from 184 infertile women (case group and 100 pregnant women (control group. The frequency of specific IgG and IgM anti-C. trachomatis antibodies were evaluated using ELISA method. Results: The frequency of IgG anti-C. trachomatis antibody in the control and case groups was 18% and 35.88%, respectively. IgM anti-C. trachomatis antibody was found in 2% of controls and 5.44% of infertile women. Our results showed the significant differences between the case and control groups in anti-C. trachomatis antibodies (IgG, p=0.035 and IgM, p=0.004. Also, no significant relation was seen between the frequency of anti-C. trachomatis antibodies and age, location, and tubal factor infertility in our two study groups. Conclusion: According to high frequency of antibody anti-C. trachomatis among infertile women in competition to the control group, evaluation and treatment of Chlamydia infections is necessary in these patients

Diabody construct of ior-CEA1. Pre-clinical studies for therapeutic application

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Pimentel, G.; Ravelo, R.; Miranda, M.; Sanchez, I.; Perez, L.; Ayala, M.; Gavilondo, J.

2007-01-01

Full text: The classic radioimmunotherapy is based on transporting to the tumor, the necessary activity of a therapeutic isotope using a monoclonal antibody (MAb) against tumor associated antigen, which constitutes an ideal vehicle given its inherent specificity. In this sense, the immunoglobulin (Ig) has some severe practical limitations due to its unhappy pharmacokinetics, relatively high molecular weight (150 kDa) and slower clearance. Likewise the Ig molecule presents a poor diffusion through the tumor mass and a relative high immunogenicity. The solution to these problems has been offered by genetic engineering, methods where the multivalent recombinant fragments have become the paradigm of design of constructed molecules. They are able to retain the specificity of the parental antibody and affinity, with reduced immunogenicity and improved pharmacokinetics. The monoclonal antibody ior-CEA1 has been employed for the diagnosis of primary tumors, recurrences and metastatic disease, and has also been used extensively in the daily clinical practice as well. Inserted in this rebirth of the antibodies, this report explores the use of a new smaller molecular weight multivalent analogue of the parent ior-CEA1 antibody to be used for the diagnosis and therapy of CEA-expressing malignant tumors such as colorectal, lung, ovary among others. The dimeric scFv-ior- CEA1 construct was produced in the Centre for Genetic Engineering and Biotechnology and displayed to bind CEA epitope with a similar binding affinity to that of the murine IgG. Method: Labelling was achieved using Chloramine T, with a molar ration of Chloramine T:Tyrosine of 2.5. For the comparison of the immunoreactivity of labeled and unlabelled diabodies, was plotted the specific union vs the antibody concentration for both molecules and adjusted to a straight line. The immunoreactivity was also assayed using size-exclusion FPLC to evaluate their antigen-binding capacities after radiolabelling. Seventy

Analyses of functions of an anti-PD-L1/TGFβR2 bispecific fusion protein (M7824).

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Jochems, Caroline; Tritsch, Sarah R; Pellom, Samuel Troy; Su, Zhen; Soon-Shiong, Patrick; Wong, Hing C; Gulley, James L; Schlom, Jeffrey

2017-09-26

M7824 (MSB0011359C) is a novel first-in-class bifunctional fusion protein consisting of a fully human IgG1 anti-PD-L1 monoclonal antibody (with structural similarities to avelumab) linked to the extracellular domain of two TGFβ receptor 2 (TGFβR2) molecules serving as a TGFβ Trap. Avelumab has demonstrated clinical activity in a range of human cancers and has been approved by the Food and Drug Administration for the therapy of Merkel cell and bladder carcinomas. Preclinical studies have shown this anti-PD-L1 is capable of mediating antibody-dependent cell-mediated cytotoxicity (ADCC). In the studies reported here, it is shown that M7824 is also capable of mediating ADCC of a wide range of human carcinoma cells in vitro , employing natural killer (NK) cells as effectors, albeit not as potent as anti-PD-L1 employing some tumor cells as targets. The addition of the IL-15 superagonist fusion protein complex ALT-803 enhanced the ADCC capacity of both anti-PD-L1 and M7824, and to levels that both agents now demonstrated similar levels of ADCC of tumor cells. TGFβ is a known immunosuppressive entity. Studies reported here show TGFβ1 induced reduction of several NK activation markers as well as reduction of endogenous NK lytic activity and NK-mediated ADCC of tumor cells. These phenomena could be reduced or mitigated, however, by M7824, but not by anti-PD-L1. M7824, but not anti-PD-L1, was also shown to reduce the immunosuppressive activity of regulatory T cells on human CD4 + T-cell proliferation. These studies thus demonstrate the dual functionalities of M7824 and provide the rationale for its further clinical development.

Relationship between recurrent spontaneous abortion and anti-β2-glycoprotein I antibody

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Liu Jingzhu; Hu Jing; Zhang Shiping; Zhang Shuang; Lin Li; Fan Jing

2008-01-01

Objective: To explore the relationship between recurrent spontaneous abortion (RSA) and anti-β 2 - glycoprotein I (anti-β 2 -GP I) antibody. Methods: The levels of anti-β 2 -GP I antibody in serum from 81 RSA patients and 39 normal women were detected by ELISA. Results: The positive rate of anti-β 2 -GP I in RSA patients (42.0%) was obviously higher than that in normal women (7.7 %) (P 2 -GP I IgG in statistics between RSA patients (40.8%) and normal women (7.7%) (P 2 -GP I IgM in statistics between RSA patients and normal women (P>0.05). There was no difference of the positive rate of anti-β 2 -GP I in statistics between early and late, as well as between 2 times and more than 2 times abortions of RSA (P>0.05). Conclusion: The anti-β 2 -GP I antibody is related to RSA, and it may be regarded as a immunological assistant diagnostic index for RSA. (authors)

Simple and efficient generation of virus-specific T cells for adoptive therapy using anti-4-1BB antibody.

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Imahashi, Nobuhiko; Nishida, Tetsuya; Goto, Tatsunori; Terakura, Seitaro; Watanabe, Keisuke; Hanajiri, Ryo; Sakemura, Reona; Imai, Misa; Kiyoi, Hitoshi; Naoe, Tomoki; Murata, Makoto

2015-01-01

Although recent studies of virus-specific T-cell (VST) therapy for viral infections after allogeneic hematopoietic stem cell transplantation have shown promising results, simple and less time-intensive and labor-intensive methods are required to generate VSTs for the wider application of VST therapy. We investigated the efficacy of anti-CD28 and anti-4-1BB antibodies, which can provide T cells with costimulatory signals similar in strength to those of antigen-presenting cells, in generating VSTs. When peripheral blood mononuclear cells were stimulated with viral peptides together with isotype control, anti-CD28, or anti-4-1BB antibodies, anti-4-1BB antibodies yielded the highest numbers of VSTs, which were on an average 7.9 times higher than those generated with isotype control antibody. The combination of anti-CD28 and anti-4-1BB antibodies did not result in increased numbers of VSTs compared with anti-4-1BB antibody alone. Importantly, the positive effect of anti-4-1BB antibody was observed regardless of the epitopes of the VSTs. In contrast, the capacity of dendritic cells (DCs) to generate VSTs differed considerably depending on the epitopes of the VSTs. Furthermore, the numbers of VSTs generated with DCs were at most similar to those generated with the anti-4-1BB antibody. Generation of VSTs with anti-4-1BB antibody did not result in excessive differentiation or deteriorated function of the generated VSTs compared with those generated with control antibody or DCs. In conclusion, VSTs can be generated rapidly and efficiently by simply stimulating peripheral blood mononuclear cells with viral peptide and anti-4-1BB antibody without using antigen-presenting cells. We propose using anti-4-1BB antibody as a novel strategy to generate VSTs for adoptive therapy.

Monoclonal anti-elastin antibody labelled with technetium-99m

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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)

Anti-pentraxin 3 auto-antibodies might be protective in lupus nephritis: a large cohort study.

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Yuan, Mo; Tan, Ying; Pang, Yun; Li, Yong-Zhe; Song, Yan; Yu, Feng; Zhao, Ming-Hui

2017-11-01

Anti-pentraxin 3 (PTX3) auto-antibodies were found to be associated with the absence of renal involvement in systemic lupus erythematosus (SLE). This study is to investigate the prevalence of anti-PTX3 auto-antibodies and their clinical significance based on a large Chinese lupus nephritis cohort. One hundred and ninety-six active lupus nephritis patients, 150 SLE patients without clinical renal involvement, and 100 healthy controls were enrolled. Serum anti-PTX3 auto-antibodies and PTX3 levels were screened by enzyme-linked immunosorbent assay (ELISA). The associations between anti-PTX3 auto-antibodies and clinicopathological parameters in lupus nephritis were further analyzed. Anti-PTX3 auto-antibodies were less prevalent in active lupus nephritis patients compared with SLE without renal involvement (19.4% (38/196) versus 40.7% (61/150), p auto-antibodies were negatively correlated with proteinuria in lupus nephritis (r = -.143, p = .047). The levels of proteinuria, serum creatinine, and the prevalence of thrombotic microangiopathy were significantly higher in patients with higher PTX3 levels (≥3.207 ng/ml) and without anti-PTX3 auto-antibodies compared with patients with lower PTX3 levels (auto-antibodies (4.79 (3.39-8.28) versus 3.95 (1.78-7.0), p = .03; 168.84 ± 153.63 versus 101.44 ± 47.36, p = .01; 34.1% (14/41) versus 0% (0/9), p = .04; respectively). Anti-PTX3 auto-antibodies were less prevalent in active lupus nephritis patients compared with SLE without renal involvement and associated with less severe renal damage, especially with the combined evaluation of serum PTX3 levels.

Targeting Malignant Brain Tumors with Antibodies

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Rok Razpotnik

2017-09-01

Full Text Available Antibodies have been shown to be a potent therapeutic tool. However, their use for targeting brain diseases, including neurodegenerative diseases and brain cancers, has been limited, particularly because the blood–brain barrier (BBB makes brain tissue hard to access by conventional antibody-targeting strategies. In this review, we summarize new antibody therapeutic approaches to target brain tumors, especially malignant gliomas, as well as their potential drawbacks. Many different brain delivery platforms for antibodies have been studied such as liposomes, nanoparticle-based systems, cell-penetrating peptides (CPPs, and cell-based approaches. We have already shown the successful delivery of single-chain fragment variable (scFv with CPP as a linker between two variable domains in the brain. Antibodies normally face poor penetration through the BBB, with some variants sufficiently passing the barrier on their own. A “Trojan horse” method allows passage of biomolecules, such as antibodies, through the BBB by receptor-mediated transcytosis (RMT. Such examples of therapeutic antibodies are the bispecific antibodies where one binding specificity recognizes and binds a BBB receptor, enabling RMT and where a second binding specificity recognizes an antigen as a therapeutic target. On the other hand, cell-based systems such as stem cells (SCs are a promising delivery system because of their tumor tropism and ability to cross the BBB. Genetically engineered SCs can be used in gene therapy, where they express anti-tumor drugs, including antibodies. Different types and sources of SCs have been studied for the delivery of therapeutics to the brain; both mesenchymal stem cells (MSCs and neural stem cells (NSCs show great potential. Following the success in treatment of leukemias and lymphomas, the adoptive T-cell therapies, especially the chimeric antigen receptor-T cells (CAR-Ts, are making their way into glioma treatment as another type of cell

Anti-hLAMP2-antibodies and dual positivity for anti-GBM and MPO-ANCA in a patient with relapsing pulmonary-renal syndrome

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Kistler Thomas

2011-06-01

Full Text Available Abstract Background Pulmonary-renal syndrome associated with anti-glomerular basement membrane (GBM antibodies, also known as Goodpasture's syndrome, is a rare but acute and life-threatening condition. One third of patients presenting as anti-GBM antibody positive pulmonary-renal syndrome or rapidly progressive glomerulonephritis are also tested positive for anti-neutrophil cytoplasmic antibodies (ANCA. Whilst anti-GBM disease is considered a non-relapsing condition, the long-term course of double-positive patients is less predictable. Case Presentation We report a patient with such dual positivity, who presented with pulmonary hemorrhage, crescentic glomerulonephritis and membranous nephropathy. Plasmapheresis in combination with immunosuppresive therapy led to a rapid remission but the disease relapsed after two years. The serum of the patient was tested positive for antibodies to human lysosomal membrane protein 2 (hLAMP2, a novel autoantigen in patients with active small-vessel vasculitis (SVV. The anti-hLAMP2 antibody levels correlated positively with clinical disease activity in this patient. Conclusion We hypothesize that this antibody may indicate a clinical course similar to ANCA-associated vasculitis in double-positive patients. However, this needs to be confirmed on comprehensive patient cohorts.

Correlation of anti C1Q antibodies with disease activity in patients with systemic lupus erythematosus

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Riaz, M.O.; Ahmed, T.A.

2016-01-01

Objective: To study the correlation of anti C1q antibodies with disease activity in patients with systemic lupus erythematosus (SLE). Study Design: Cross sectional, observational study. Place and Duration of study: The Department of Immunology, Armed Forces Institute of Pathology, Rawalpindi in collaboration with Military Hospital, Rawalpindi, Pakistan Institute of Medical Sciences, Islamabad and Benazir Bhutto Hospital, Rawalpindi, from Jan 2012 to Dec 2013. Material and Methods: Patients with a clinical diagnosis of SLE were included in the study on fulfilling revised American College of Rheumatology (ACR) criteria (1997). Main outcome measures were SLE disease activity index (SLEDAI) score and anti C1q antibody levels in serum. SLEDAI scores were calculated for each patient on the basis of physical examination, patient interviews and previous clinical records. Anti C1q antibody levels in the serum were determined by enzyme-linked immunosorbent assay (ELISA) and correlated with the SLEDAI scores by calculating Pearson's correlation coefficient 'r'. The cutoff value for anti C1q antibody positivity in the serum was determined by evaluating the serum levels of anti C1q antibodies in 25 healthy subjects and was 12 U/ml. Results: Six male and forty nine female SLE patients with an age range of 16-47 years (mean 34.5 years) and 8-70 years (mean 31.7 years) respectively were studied. The correlation between anti C1q levels and SLEDAI scores in all patients was demonstrated by calculating the correlation coefficient and was not significant (r=0.19, p=0.14). However, there was an inverse correlation between anti C1q levels and SLEDAI scores in patients with severe disease and this was statistically significant (r=-0.448, p=0.037). The difference in anti C1q antibody positivity between patients with and without nephritis was not significant. The anti C1q antibody levels correlated poorly with anti double stranded deoxyribonucleic acid (dsDNA) antibody positivity. A

Anti-MOG antibody-positive ADEM following infectious mononucleosis due to a primary EBV infection: a case report.

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Nakamura, Yoshitsugu; Nakajima, Hideto; Tani, Hiroki; Hosokawa, Takafumi; Ishida, Shimon; Kimura, Fumiharu; Kaneko, Kimihiko; Takahashi, Toshiyuki; Nakashima, Ichiro

2017-04-19

Anti-Myelin oligodendrocyte glycoprotein (MOG) antibodies are detected in various demyelinating diseases, such as pediatric acute disseminated encephalomyelitis (ADEM), recurrent optic neuritis, and aquaporin-4 antibody-seronegative neuromyelitis optica spectrum disorder. We present a patient who developed anti-MOG antibody-positive ADEM following infectious mononucleosis (IM) due to Epstein-Barr virus (EBV) infection. A 36-year-old healthy man developed paresthesia of bilateral lower extremities and urinary retention 8 days after the onset of IM due to primary EBV infection. The MRI revealed the lesions in the cervical spinal cord, the conus medullaris, and the internal capsule. An examination of the cerebrospinal fluid revealed pleocytosis. Cell-based immunoassays revealed positivity for anti-MOG antibody with a titer of 1:1024 and negativity for anti-aquaporin-4 antibody. His symptoms quickly improved after steroid pulse therapy followed by oral betamethasone. Anti-MOG antibody titer at the 6-month follow-up was negative. This case suggests that primary EBV infection would trigger anti-MOG antibody-positive ADEM. Adult ADEM patients can be positive for anti-MOG antibody, the titers of which correlate well with the neurological symptoms.

Modulation of Dengue/Zika Virus Pathogenicity by Antibody-Dependent Enhancement and Strategies to Protect Against Enhancement in Zika Virus Infection

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Rekha Khandia

2018-04-01

Full Text Available Antibody-dependent enhancement (ADE is a phenomenon in which preexisting poorly neutralizing antibodies leads to enhanced infection. It is a serious concern with mosquito-borne flaviviruses such as Dengue virus (DENV and Zika virus (ZIKV. In vitro experimental evidences have indicated the preventive, as well as a pathogenicity-enhancing role, of preexisting DENV antibodies in ZIKV infections. ADE has been confirmed in DENV but not ZIKV infections. Principally, the Fc region of the anti-DENV antibody binds with the fragment crystallizable gamma receptor (FcγR, and subsequent C1q interactions and immune effector functions are responsible for the ADE. In contrast to normal DENV infections, with ADE in DENV infections, inhibition of STAT1 phosphorylation and a reduction in IRF-1 gene expression, NOS2 levels, and RIG-1 and MDA-5 expression levels occurs. FcγRIIA is the most permissive FcγR for DENV-ADE, and under hypoxic conditions, hypoxia-inducible factor-1 alpha transcriptionally enhances expression levels of FcγRIIA, which further enhances ADE. To produce therapeutic antibodies with broad reactivity to different DENV serotypes, as well as to ZIKV, bispecific antibodies, Fc region mutants, modified Fc regions, and anti-idiotypic antibodies may be engineered. An in-depth understanding of the immunological and molecular mechanisms of DENV-ADE of ZIKV pathogenicity will be useful for the design of common and safe therapeutics and prophylactics against both viral pathogens. The present review discusses the role of DENV antibodies in modulating DENV/ZIKV pathogenicity/infection and strategies to counter ADE to protect against Zika infection.

Detection of anti-liver cytosol antibody type 1 (anti-LC1) by immunodiffusion, counterimmunoelectrophoresis and immunoblotting: comparison of different techniques.

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Muratori, L; Cataleta, M; Muratori, P; Manotti, P; Lenzi, M; Cassani, F; Bianchi, F B

1995-12-01

Liver cytosol specific antibody type 1 (anti-LC1) was first described in a proportion of patients with liver/kidney microsomal antibody type 1 (anti-LKM1)-positive autoimmune hepatitis (AIH) and is routinely evaluated by immunodiffusion (ID). Using human liver cytosol as the source of antigen, we have used ID, counterimmunoelectrophoresis (CIE) and immunoblotting (IB), to test sera from 167 patients with documented chronic liver diseases of different etiology. 15 patients had antinuclear antibody (ANA) and/or smooth muscle antibody (SMA)-positive AIH, 13 had anti-LKM1-positive AIH, four had ANA/SMA/anti-LKM1-negative AIH, 76 had anti-LKM1-positive hepatitis C (recently renamed unclassified chronic hepatitis-UCH), 40 had chronic hepatitis C, 15 had chronic hepatitis B, and 4 had chronic hepatitis D. A precipitin line of identity with an anti-LC1 reference serum was detected both by ID and CIE in 16 patients: six with anti-LKM1-positive 'definite' AIH, four with ANA/SMA/anti-LKM1-negative 'definite' AIH, and six with anti-LKM1-positive UCH. By IB, 14 out of the 16 anti-LC1-positive sera (87.5%) reacted with a 58 kDa human liver cytosolic polypeptide, whereas three out of 16 (19%) recognised an additional 60 kDa band. Compared to ID, CIE is more economical in terms of both time and reagents and provides more clear-cut results. The 58 kDa reactivity by IB was detectable in nearly all CIE/ID anti-LC1-positive patients, was not found among CIE/ID anti-LC1-negative patients. In conclusion, CIE is the ideal screening test for the detection of anti-LC1, an autoantibody that can be regarded as an additional serological marker of AIH and is especially useful in ANA/SMA/anti-LKM1 negative cases.

Anti-Idiotypic Antibodies Specific to prM Monoantibody Prevent Antibody Dependent Enhancement of Dengue Virus Infection

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Miao Wang

2017-05-01

Full Text Available Dengue virus (DENV co-circulates as four serotypes (DENV1-4. Primary infection only leads to self-limited dengue fever. But secondary infection with another serotype carries a higher risk of increased disease severity, causing life-threatening dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS. Serotype cross-reactive antibodies facilitate DENV infection in Fc-receptor-bearing cells by promoting virus entry via Fcγ receptors (FcγR, a process known as antibody dependent enhancement (ADE. Most studies suggested that enhancing antibodies were mainly specific to the structural premembrane protein (prM of DENV. However, there is still no effective drugs or vaccines to prevent ADE. In this study, we firstly confirmed that both DENV-2 infected human sera (anti-DENV-2 and DENV-2 prM monoclonal antibody (prM mAb could significantly enhance DENV-1 infection in K562 cells. Then we developed anti-idiotypic antibodies (prM-AIDs specific to prM mAb by immunizing of Balb/c mice. Results showed that these polyclonal antibodies can dramatically reduce ADE phenomenon of DENV-1 infection in K562 cells. To further confirm the anti-ADE effect of prM-AIDs in vivo, interferon-α and γ receptor-deficient mice (AG6 were used as the mouse model for DENV infection. We found that administration of DENV-2 prM mAb indeed caused a higher DENV-1 titer as well as interleukin-10 (IL-10 and alaninea minotransferase (ALT in mice infected with DENV-1, similar to clinical ADE symptoms. But when we supplemented prM-AIDs to DENV-1 challenged AG6 mice, the viral titer, IL-10 and ALT were obviously decreased to the negative control level. Of note, the number of platelets in peripheral blood of prM-AIDs group were significantly increased at day 3 post infection with DENV-1 compared that of prM-mAb group. These results confirmed that our prM-AIDs could prevent ADE not only in vitro but also in vivo, suggested that anti-idiotypic antibodies might be a new choice to be considered to

Anti-Idiotypic Antibodies Specific to prM Monoantibody Prevent Antibody Dependent Enhancement of Dengue Virus Infection.

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Wang, Miao; Yang, Fan; Huang, Dana; Huang, Yalan; Zhang, Xiaomin; Wang, Chao; Zhang, Shaohua; Zhang, Renli

2017-01-01

Dengue virus (DENV) co-circulates as four serotypes (DENV1-4). Primary infection only leads to self-limited dengue fever. But secondary infection with another serotype carries a higher risk of increased disease severity, causing life-threatening dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS). Serotype cross-reactive antibodies facilitate DENV infection in Fc-receptor-bearing cells by promoting virus entry via Fcγ receptors (FcγR), a process known as antibody dependent enhancement (ADE). Most studies suggested that enhancing antibodies were mainly specific to the structural premembrane protein (prM) of DENV. However, there is still no effective drugs or vaccines to prevent ADE. In this study, we firstly confirmed that both DENV-2 infected human sera (anti-DENV-2) and DENV-2 prM monoclonal antibody (prM mAb) could significantly enhance DENV-1 infection in K562 cells. Then we developed anti-idiotypic antibodies (prM-AIDs) specific to prM mAb by immunizing of Balb/c mice. Results showed that these polyclonal antibodies can dramatically reduce ADE phenomenon of DENV-1 infection in K562 cells. To further confirm the anti-ADE effect of prM-AIDs in vivo , interferon-α and γ receptor-deficient mice (AG6) were used as the mouse model for DENV infection. We found that administration of DENV-2 prM mAb indeed caused a higher DENV-1 titer as well as interleukin-10 (IL-10) and alaninea minotransferase (ALT) in mice infected with DENV-1, similar to clinical ADE symptoms. But when we supplemented prM-AIDs to DENV-1 challenged AG6 mice, the viral titer, IL-10 and ALT were obviously decreased to the negative control level. Of note, the number of platelets in peripheral blood of prM-AIDs group were significantly increased at day 3 post infection with DENV-1 compared that of prM-mAb group. These results confirmed that our prM-AIDs could prevent ADE not only in vitro but also in vivo , suggested that anti-idiotypic antibodies might be a new choice to be considered to treat

Characterization of changes in serum anti-glycan antibodies in Crohn's disease--a longitudinal analysis.

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Florian Rieder

Full Text Available INTRODUCTION: Anti-glycan antibodies are a promising tool for differential diagnosis and disease stratification of patients with Crohn's disease (CD. We longitudinally assessed level and status changes of anti-glycan antibodies over time in individual CD patients as well as determinants of this phenomenon. METHODS: 859 serum samples derived from a cohort of 253 inflammatory bowel disease (IBD patients (207 CD, 46 ulcerative colitis (UC were tested for the presence of anti-laminarin (Anti-L, anti-chitin (Anti-C, anti-chitobioside (ACCA, anti-laminaribioside (ALCA, anti-mannobioside (AMCA and anti-Saccharomyces cerevisiae (gASCA antibodies by ELISA. All patients had at least two and up to eleven serum samples taken during the disease course. RESULTS: Median follow-up time for CD was 17.4 months (Interquartile range (IQR 8.0, 31.6 months and for UC 10.9 months (IQR 4.9, 21.0 months. In a subgroup of CD subjects marked changes in the overall immune response (quartile sum score and levels of individual markers were observed over time. The marker status (positive versus negative remained widely stable. Neither clinical phenotype nor NOD2 genotype was associated with the observed fluctuations. In a longitudinal analysis neither changes in disease activity nor CD behavior led to alterations in the levels of the glycan markers. The ability of the panel to discriminate CD from UC or its association with CD phenotypes remained stable during follow-up. In the serum of UC patients neither significant level nor status changes were observed. CONCLUSIONS: While the levels of anti-glycan antibodies fluctuate in a subgroup of CD patients the antibody status is widely stable over time.

Pulmonary biology of anti-interleukin 5 antibodies

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RW Egan

1997-12-01

Full Text Available Interleukin 5 (IL-5 is a critical cytokine for the maturation of eosinophil precursors to eosinophils in the bone marrow and those eosinophils then accumulate in the lungs during asthma. We have studied anti IL-5 antibodies on allergic responses in mice, guinea pigs and monkeys and are extending this experiment into humans with a humanized antibody. In a monkey model of pulmonary inflammation and airway hyperreactivity, we found that the TRFK-5 antibody blocked both responses for three months following a single dose of 0.3 mg/kg, i.v. This antibody also blocked lung eosinophilia in mice by inhibiting release from the bone marrow. To facilitate multiple dosing and to reduce immunogenicity in humans, we prepared Sch 55700, a humanized antibody against IL-5. Sch 55700 was also active against lung eosinophilia in allergic monkeys and mice and against pulmonary eosinophilia and airway hyperresponsiveness in guinea pigs. Furthermore, as opposed to steroids, Sch 55700 did not cause immunosuppression in guinea pigs. Studies with this antibody in humans will be critical to establishing the therapeutic potential of IL-5 inhibition.

[Prokaryotic expression of Nanog gene and preparation of anti-Nanog antibody].

Science.gov (United States)

Li, Jun; Wang, Xiao-min; Dou, Zhong-ying; Li, Yong

2012-07-01

To express Nanog fusion protein in Escherichia coli ( E.coli), and to prepare rabbit anti-mouse polyclonal antibodies to the Nanog fusion protein. Mouse Nanog gene was amplified from the pNA992 recombinant plasmid and inserted into pET-32a vector to construct a recombinant expression vector pET-32a-Nanog. The recombinant vector was transfected into E.coli BL21 and induced by IPTG to express in them. The acquired Nanog fusion protein was purified with HisTrap affinity column and injected as an antigen into rabbits for preparing polyclonal antibodies. At last, the titer and specificity of the polyclonal antibodies were analyzed with indirect ELISA, Western blotting and immunocytochemical staining, respectively. The recombinant expression vector pET-32a-Nanog was successfully prepared, transfected and induced to obtain the high expression of the Nanog fusion protein in a form of inclusion bodies in E.coli. After purification, its purity was up to 97%. The titer of anti-Nanog antibodies was 1:32 000 in the immunized rabbit serum, and exhibited a high specificity to Nanog protein. The rabbit anti-mouse polyclonal antibodies have been prepared successfully with a high titer and specificity to the Nanog fusion protein.

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

Radiometric immunosorbent assay for the detection of anti-hormone-binding protein antibodies

International Nuclear Information System (INIS)

Pierce, E.A.; Dame, M.C.; DeLuca, H.F.

1986-01-01

A radiometric immunosorbent assay (RISA) for the detection of monoclonal antibodies to hormone-binding proteins has been developed. The assay involves incubating hybridoma supernatants in microtiter wells that have been coated with goat anti-mouse IgG antibodies. Any mouse IgG in the test supernatant is thus specifically retained in the wells. Radioactive ligand-binding protein complexes are then incubated in the wells. The presence of anti-binding protein antibodies in the supernatant is indicated by specific retention of radioactive ligand-binding protein complexes in the wells. Crude antigen preparations, such as tissue homogenates, can be used to detect antibodies. The assay is capable of detecting antibody at concentrations 20 ng/ml (approx. 100 pM IgG). The RISA has been used successfully to screen for monoclonal antibodies to the intracellular receptor for 1,25-dihydroxyvitamin D 3 and should be useful for the detection of antibodies to ligand-binding proteins in general

The antibody response against human and chimeric anti-TNF therapeutic antibodies primarily targets the TNF binding region

NARCIS (Netherlands)

van Schie, K. A.; Hart, M. H.; de Groot, E. R.; Kruithof, S.; Aarden, L. A.; Wolbink, G. J.; Rispens, T.

2015-01-01

In a subset of patients, anti tumour necrosis factor (TNF) therapeutic antibodies are immunogenic, resulting in the formation of antidrug antibodies (ADAs). Neutralising ADAs compete with TNF for its binding site and reduces the effective serum concentration, causing clinical non-response. It is

Multiple recurrences of anti-glomerular basement membrane disease with variable antibody detection: can the laboratory be trusted?

OpenAIRE

Liu, Patricia; Waheed, Sana; Boujelbane, Lamya; Maursetter, Laura J.

2016-01-01

Anti-glomerular basement membrane (GBM) disease is commonly a monophasic illness. We present the case of multiple recurrences of anti-GBM disease with varying serum anti-GBM antibody findings. A 33-year-old female tobacco user presenting with hematuria was diagnosed with anti-GBM disease by renal biopsy. Five years later, she presented with alveolar hemorrhage and positive anti-GBM antibody. She presented a third time with alveolar hemorrhage but undetectable anti-GBM antibody. With each occu...

Detection of serum anti-sperm antibody in infertile couples with dot-immunogold filtration assay (DIGFA)

International Nuclear Information System (INIS)

Xie Xiaoxian

2005-01-01

Objective: To develop a new method for rapid detection of serum anti-sperm antibody in infertile couples. Methods: Human sperm antigen was prepared from pooled semen specimens of fertile males. Nitro-cellulose membrane was used as solid-phase carrier of the antigen. Colloidal gold pellet combined goat anti-human IgG was taken as labelled antibody. A dot-immunogold filtration assay system was established for test of serum anti-human sperm antibody. Serum specimens from 137 infertile couples were tested and the result compared with flat from ELISA. Results: The human sperm antigen would react with the anti-sperm antibody in the tested serum over the cellulose membrane through filtration and the result could be read with naked eye within 6 minutes. In this study of 137 infertile coupled, the anti-sperm antibody was positive in 21.9% of the female serum specimens and 13.19% of the males. Compared with the result from ELISA, the consistency rate was 96.1%. The sensitivity of the assay was 90.2% and specificity was 95.4%. The p reparation was stable after 6 months refrigerator storage. Conclusion: This newly developed DIGFA is very adequate for rap id detection of anti-sperm antibody and deserves popularization. (authors)

Human anti-luteinizing hormone-releasing hormone antibodies in patients treated with synthetic luteinizing hormone-releasing hormone

International Nuclear Information System (INIS)

Meakin, J.L.; Keogh, E.J.; Martin, C.E.

1985-01-01

One hundred sixty-three patients who were given synthetic LH-RH therapeutically underwent monitoring of serum IgG anti-LH-RH antibodies. Five of the patients showed specific binding to antibodies. Development of anti-LH-RH antibodies was not limited to those patients with a congenital deficiency of LH-RH. Urticarial responses occurred in four patients, only one of whom had IgG antibodies. Patients who had IgG antibodies or an urticarial response underwent monitoring of their serum IgE anti-LH-RH antibodies, but none had a positive binding response. The refractory state which has been reported in patients in whom similar antibodies to LH-RH develop was not invariably observed among these patients

The Role of Anti-Drug Antibodies in the Pharmacokinetics, Disposition, Target Engagement, and Efficacy of a GITR Agonist Monoclonal Antibody in Mice.

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Brunn, Nicholas D; Mauze, Smita; Gu, Danling; Wiswell, Derek; Ueda, Roanna; Hodges, Douglas; Beebe, Amy M; Zhang, Shuli; Escandón, Enrique

2016-03-01

Administration of biologics to enhance T-cell function is part of a rapidly growing field of cancer immunotherapy demonstrated by the unprecedented clinical success of several immunoregulatory receptor targeting antibodies. While these biologic agents confer significant anti-tumor activity through targeted immune response modulation, they can also elicit broad immune responses potentially including the production of anti-drug antibodies (ADAs). DTA-1, an agonist monoclonal antibody against GITR, is a highly effective anti-tumor treatment in preclinical models. We demonstrate that repeated dosing with murinized DTA-1 (mDTA-1) generates ADAs with corresponding reductions in drug exposure and engagement of GITR on circulating CD3(+) CD4(+) T cells, due to rapid hepatic drug uptake and catabolism. Mice implanted with tumors after induction of preexisting mDTA-1 ADA show no anti-tumor efficacy when given 3 mg/kg mDTA-1, an efficacious dose in naive mice. Nonetheless, increasing mDTA-1 treatment to 30 mg/kg in ADA-positive mice restores mDTA-1 exposure and GITR engagement on circulating CD3(+) CD4(+) T cells, thereby partially restoring anti-tumor efficacy. Formation of anti-mDTA-1 antibodies and changes in drug exposure and disposition does not occur in GITR(-/-) mice, consistent with a role for GITR agonism in humoral immunity. Finally, the administration of muDX400, a murinized monoclonal antibody against the checkpoint inhibitor PD-1, dosed alone or combined with mDTA-1 did not result in reduced muDX400 exposure, nor did it change the nature of the anti-mDTA-1 response. This indicates that anti-GITR immunogenicity may not necessarily impact the pharmacology of coadministered monoclonal antibodies, supporting combination immunomodulatory strategies. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

Novel anti-HER2 monoclonal antibodies: synergy and antagonism with tumor necrosis factor-α

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Ceran Ceyhan

2012-10-01

Full Text Available Abstract Background One-third of breast cancers display amplifications of the ERBB2 gene encoding the HER2 kinase receptor. Trastuzumab, a humanized antibody directed against an epitope on subdomain IV of the extracellular domain of HER2 is used for therapy of HER2-overexpressing mammary tumors. However, many tumors are either natively resistant or acquire resistance against Trastuzumab. Antibodies directed to different epitopes on the extracellular domain of HER2 are promising candidates for replacement or combinatorial therapy. For example, Pertuzumab that binds to subdomain II of HER2 extracellular domain and inhibits receptor dimerization is under clinical trial. Alternative antibodies directed to novel HER2 epitopes may serve as additional tools for breast cancer therapy. Our aim was to generate novel anti-HER2 monoclonal antibodies inhibiting the growth of breast cancer cells, either alone or in combination with tumor necrosis factor-α (TNF-α. Methods Mice were immunized against SK-BR-3 cells and recombinant HER2 extracellular domain protein to produce monoclonal antibodies. Anti-HER2 antibodies were characterized with breast cancer cell lines using immunofluorescence, flow cytometry, immunoprecipitation, western blot techniques. Antibody epitopes were localized using plasmids encoding recombinant HER2 protein variants. Antibodies, either alone or in combination with TNF-α, were tested for their effects on breast cancer cell proliferation. Results We produced five new anti-HER2 monoclonal antibodies, all directed against conformational epitope or epitopes restricted to the native form of the extracellular domain. When tested alone, some antibodies inhibited modestly but significantly the growth of SK-BR-3, BT-474 and MDA-MB-361 cells displaying ERBB2 amplification. They had no detectable effect on MCF-7 and T47D cells lacking ERBB2 amplification. When tested in combination with TNF-α, antibodies acted synergistically on SK-BR-3 cells

Regional and systemic distribution of anti-tumor x anti-CD3 heteroaggregate antibodies and cultured human peripheral blood lymphocytes in a human colon cancer xenograft

International Nuclear Information System (INIS)

Nelson, H.; Ramsey, P.S.; Kerr, L.A.; McKean, D.J.; Donohue, J.H.

1990-01-01

Anti-tumor antibody (317G5) covalently coupled to an anti-CD3 antibody (OKT3) produces a heteroaggregate (HA) antibody that can target PBL to lyse tumor cells expressing the appropriate tumor Ag. The i.v. and i.p. distribution of radiolabeled HA antibody 317G5 x OKT3 and of radiolabeled cultured human PBL were studied in athymic nude mice bearing solid intraperitoneal tumor established from the human colon tumor line, LS174T. Mice were injected with 125I-labeled HA antibody, 125I-labeled anti-tumor mAb, or 111In-labeled PBL, and at designated timepoints tissues were harvested and measured for radioactivity. 125I-317G5 x OKT3 localized specifically to tumor sites. Tumor radioactivity levels (percent injected dose/gram) were lower with 125I-317G5 x OKT3 HA antibody than with 125I-317G5 anti-tumor mAb, but were similar to levels reported for other anti-tumor mAb. The major difference in radioactivity levels observed between i.v. and i.p. administration of 125I-317G5 x OKT3 was an increase in hepatic radioactivity after i.v. HA antibody administration. HA antibodies produced from F(ab')2 fragments, which exhibit decreased m. w. and decreased Fc receptor-mediated binding, demonstrated improved tumor:tissue ratios as compared to intact antibody HA. 125I-317G5 F(ab')2 x OKT3 F(ab')2 antibody levels were equivalent to intact HA antibody levels in tumor, but were lower than intact HA antibody levels in the blood, bowel, and liver. Tumor:bowel ratios (20:1 at 48 h) were highest when 317G5 F(ab')2 x OKT3 F(ab')2 was injected i.p. Autoradiography confirmed that anti-tumor x anti-CD3 HA antibodies localized specifically to intraperitoneal tumor; that i.p. administered HA antibodies penetrated tumor directly; and that i.v. administered HA antibodies distributed along tumor vasculature

Immunogenicity of Anti-HLA Antibodies in Pancreas and Islet Transplantation.

Science.gov (United States)

Chaigne, Benjamin; Geneugelijk, Kirsten; Bédat, Benoît; Ahmed, Mohamed Alibashe; Hönger, Gideon; De Seigneux, Sophie; Demuylder-Mischler, Sandrine; Berney, Thierry; Spierings, Eric; Ferrari-Lacraz, Sylvie; Villard, Jean

2016-11-01

The aim of the current study was to characterize the anti-HLA antibodies before and after pancreatic islet or pancreas transplantation. We assessed the risk of anti-donor-specific antibody (DSA) sensitization in a single-center, retrospective clinical study at Geneva University Hospital. Data regarding clinical characteristics, graft outcome, HLA mismatch, donor HLA immunogenicity, and anti-HLA antibody characteristics were collected. Between January 2008 and July 2014, 18 patients received islet transplants, and 26 patients received a pancreas transplant. Eleven out of 18 patients (61.1%) in the islet group and 12 out of 26 patients (46.2%) in the pancreas group had anti-HLA antibodies. Six patients (33.3%) developed DSAs against HLA of the islets, and 10 patients (38.4%) developed DSAs against HLA of the pancreas. Most of the DSAs were at a low level. Several parameters such as gender, number of times cells were transplanted, HLA mismatch, eplet mismatch and PIRCHE-II numbers, rejection, and infection were analyzed. Only the number of PIRCHE-II was associated with the development of anti-HLA class II de novo DSAs. Overall, the development of de novo DSAs did not influence graft survival as estimated by insulin independence. Our results indicated that pretransplant DSAs at low levels do not restrict islet or pancreas transplantation [especially islet transplantation (27.8% vs. 15.4.%)]. De novo DSAs do occur at a similar rate in both pancreas and islet transplant recipients (mainly of class II), and the immunogenicity of donor HLA is a parameter that should be taken into consideration. When combined with an immunosuppressive regimen and close follow-up, development of low levels of DSAs was not found to result in reduced graft survival or graft function in the current study.

Non-association between anti-Toxoplasma gondii antibodies and ABO blood group system

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ACF Rodrigues

2011-01-01

Full Text Available Toxoplasma gondii infects humans through the gastrointestinal tract (GIT, which elicits humoral immune response with specific antibodies. The expression of the ABO blood group glycoconjugates also occurs in this same system and may influence the human susceptibility of infection by T. gondii. The aim of the present study was to investigate the association between ABO blood group phenotypes and the presence of anti-T. gondii antibodies. Data - including age, results of serology tests for T. gondii infection and ABO blood group phenotypes - were assembled from the medical records of 1,006 pregnant women attended in the Base Hospital of the Medical School of São José do Rio Preto, Brazil, between 2001 and 2004. The chi-square test was used to compare the results with the level of significance set at 5%. Of the studied cases, 64.1% (645/1006 and 35.9% (391/1006 presented respectively positive and negative serology tests for anti-T. gondii antibodies. The mean age of those who tested positive was higher than those with negative serology tests (p = 0.0004. The frequencies of ABO blood group phenotypes were similar in those with and without anti-T. gondii antibodies (p = 0.35. In conclusion, the ABO blood group system is not associated with the presence or absence of anti-T. gondii antibodies.

Radioimmunoimaging of ovarian cancer with 131I labelled CEA monoclonal antibody

International Nuclear Information System (INIS)

Hu Likuan; Li Zhen; Huo Zhenguo; Jiang Sen; Jia Shiquan

2001-01-01

Objective: To investigate radioimmunoimaging with 131 I labelled CEA McAb and its value in diagnosis and treatment of ovarian cancer. Methods: CEA McAb was labelled with 131 I by standard chloramine T procedure. The radiolabeled McAb was given intravenously to the patients. The scintigraphy was performed at different time. Results: In 105 patients with histopathology proved ovarian cancers, for 96 patients the lesions were well located with RII (true positives), for the remaining 9 patients, the results were false negative. 22/23 cases with RII diagnosed benign ovarian tumors were proved to be true negative by surgical pathology in RII. Of 96 ovarian cancers 87 were stratified into identical stages by surgical pathology all RII. 141/151 metastatic tumors were found in RII and the positive rate was as high as 93.4%. The smallest tumor defected by RII was of 1 cm in diameter. Conclusions: RII is as good as ultrasonography and CT in distinguishing benignancy and malignancy. The location, size and number of the lesions can also be determined with RII. RII of ovarian cancer with 131 I-CEA McAb is valuable and helpful in early detection of ovarian cancer. It is also helpful for clinical staging, treatment programing and prognosticating

Inflammation-Specific T1 Imaging Using Anti-Intercellular Adhesion Molecule 1 Antibody-Conjugated Gadolinium Diethylenetriaminepentaacetic Acid

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Kyu-Sil Choi

2007-03-01

Full Text Available To examine inflammatory tissue, an initial and common symptom of various types of pathogenesis, we designed inflammation-targeted T1 contrast agents prepared by bioconjugation of gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA with anti-intercellular adhesion molecule 1 (ICAM-1 antibody. The anti-ICAM-1 antibody was coupled with DTPA and was then conjugated with Gd. The specific binding of the Gd-DTPA-anti-ICAM-1 antibody complex to the ICAM-1-expressing cells was examined in the cultured endothelial cells where ICAM-1 expression was stimulated. Inflammation-specific T1 imaging was then assessed using a mouse abscess model with the 1.5-Tesla module. The Gd-DTPA-anti-ICAM-1 antibody displayed increased r1, which was two times higher than that of Gd-DTPA and showed predominant binding to cultured endothelial cells, which expressed a high level of ICAM-1. Moreover, the inflammation-specific T1 enhancement was imaged with the Gd-DTPA-anti-ICAM-1 antibody in the mouse acute inflammation model. The Gd-DTPA-anti-ICAM-1 antibody showed significantly increased vascular circulation time, which thereby offered a greater chance for its binding to the target cells. The Gd-DTPA-anti-ICAM-1 antibody displays a potential targeted T1 contrast agent specific to the inflammatory tissue that expresses ICAM-1.

Oriented immobilized anti-LDL antibody carrying poly(hydroxyethyl methacrylate) cryogel for cholesterol removal from human plasma

International Nuclear Information System (INIS)

Bereli, Nilay; Sener, Guelsu; Yavuz, Handan; Denizli, Adil

2011-01-01

Low density lipoprotein (LDL) cholesterol is a major ingredient of the plaque that collects in the coronary arteries and causes coronary heart diseases. Among the methods used for the extracorporeal elimination of LDL from intravasal volume, immunoaffinity technique using anti-LDL antibody as a ligand offers superior selectivity and specificity. Proper orientation of the immobilized antibody is the main issue in immunoaffinity techniques. In this study, anti-human β-lipoprotein antibody (anti-LDL antibody) molecules were immobilized and oriented through protein A onto poly(2-hydroxyethyl methacrylate) (PHEMA) cryogel in order to remove LDL from hypercholesterolemic human plasma. PHEMA cryogel was prepared by free radical polymerization initiated with N,N,N',N'-tetramethylene diamine (TEMED). PHEMA cryogel with a swelling degree of 8.89 g H 2 O/g and 67% macro-porosity was characterized by swelling studies, scanning electron microscope (SEM) and blood compatibility tests. All the clotting times were increased when compared with control plasma. The maximum immobilized anti-LDL antibody amount was 63.2 mg/g in the case of random antibody immobilization and 19.6 mg/g in the case of oriented antibody immobilization (protein A loading was 57.0 mg/g). Random and oriented anti-LDL antibody immobilized PHEMA cryogels adsorbed 111 and 129 mg LDL/g cryogel from hypercholesterolemic human plasma, respectively. Up to 80% of the adsorbed LDL was desorbed. The adsorption-desorption cycle was repeated 6 times using the same cryogel. There was no significant loss of LDL adsorption capacity. - Research highlights: → LDL cholesterol is a risk factor in the development of coronary heart diseases. → Antibodies against LDL are used for the selective extracorporeal removal of LDL. → Protein A is used for the oriented immobilization of anti LDL onto PHEMA cryogel. → PHEMA cryogels are biocompatible, exhibit a low pressure drop, lack diffusion resistance and viscous samples can be

Oriented immobilized anti-LDL antibody carrying poly(hydroxyethyl methacrylate) cryogel for cholesterol removal from human plasma

Energy Technology Data Exchange (ETDEWEB)

Bereli, Nilay [Department of Chemistry, Hacettepe University, Beytepe, Ankara (Turkey); Sener, Guelsu [Nanotechnology and Nanomedicine Division, Hacettepe University, Ankara (Turkey); Yavuz, Handan, E-mail: handany@hacettepe.edu.tr [Department of Chemistry, Hacettepe University, Beytepe, Ankara (Turkey); Denizli, Adil [Department of Chemistry, Hacettepe University, Beytepe, Ankara (Turkey)

2011-07-20

Low density lipoprotein (LDL) cholesterol is a major ingredient of the plaque that collects in the coronary arteries and causes coronary heart diseases. Among the methods used for the extracorporeal elimination of LDL from intravasal volume, immunoaffinity technique using anti-LDL antibody as a ligand offers superior selectivity and specificity. Proper orientation of the immobilized antibody is the main issue in immunoaffinity techniques. In this study, anti-human {beta}-lipoprotein antibody (anti-LDL antibody) molecules were immobilized and oriented through protein A onto poly(2-hydroxyethyl methacrylate) (PHEMA) cryogel in order to remove LDL from hypercholesterolemic human plasma. PHEMA cryogel was prepared by free radical polymerization initiated with N,N,N',N'-tetramethylene diamine (TEMED). PHEMA cryogel with a swelling degree of 8.89 g H{sub 2}O/g and 67% macro-porosity was characterized by swelling studies, scanning electron microscope (SEM) and blood compatibility tests. All the clotting times were increased when compared with control plasma. The maximum immobilized anti-LDL antibody amount was 63.2 mg/g in the case of random antibody immobilization and 19.6 mg/g in the case of oriented antibody immobilization (protein A loading was 57.0 mg/g). Random and oriented anti-LDL antibody immobilized PHEMA cryogels adsorbed 111 and 129 mg LDL/g cryogel from hypercholesterolemic human plasma, respectively. Up to 80% of the adsorbed LDL was desorbed. The adsorption-desorption cycle was repeated 6 times using the same cryogel. There was no significant loss of LDL adsorption capacity. - Research highlights: {yields} LDL cholesterol is a risk factor in the development of coronary heart diseases. {yields} Antibodies against LDL are used for the selective extracorporeal removal of LDL. {yields} Protein A is used for the oriented immobilization of anti LDL onto PHEMA cryogel. {yields} PHEMA cryogels are biocompatible, exhibit a low pressure drop, lack diffusion

A study on the relationship of anti-HCV antibody and hepatitis C viremia in post-transfusion hepatitis

International Nuclear Information System (INIS)

Lee, Dong Soon

1993-01-01

The specimens of blood transfusion recipients who recieved the Anti-HCV antibody positive bloods were analyzed at irregular intervals by enzyme immunoassay to measure the anti-HCV antibody and reverse transcription PCR of hepatitis C virus to evaluate the viremic states. At the same time, the specimens of anti-HCV antibody positive healthy blood donors are analyzed by the reverse transcription PCR method. We analyzed the 9 cases of anti-HCV positive blood donors by reverse transcription PCR and no cases of positive HCV reverse transcription PCR is found. The 5 patients who recieved the anti-HCV positive blood by blood transfusion was followed at irregular interval. Of 5 blood recipients, Hepatitis C virus was detected in 2 patients (40%) and Anti-HCV antibody was detected in 2 patients (40%). We suppose that in contrast to disease group (Non A non B hepatitis), the possibility of viremia in the anti-HCV positive blood donors is significantly low and the character of those antibody may be convalescent antibody after hepatitis C resolution. (Author)

A study on the relationship of anti-HCV antibody and hepatitis C viremia in post-transfusion hepatitis

Energy Technology Data Exchange (ETDEWEB)

Lee, Dong Soon [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

1993-01-01

The specimens of blood transfusion recipients who recieved the Anti-HCV antibody positive bloods were analyzed at irregular intervals by enzyme immunoassay to measure the anti-HCV antibody and reverse transcription PCR of hepatitis C virus to evaluate the viremic states. At the same time, the specimens of anti-HCV antibody positive healthy blood donors are analyzed by the reverse transcription PCR method. We analyzed the 9 cases of anti-HCV positive blood donors by reverse transcription PCR and no cases of positive HCV reverse transcription PCR is found. The 5 patients who recieved the anti-HCV positive blood by blood transfusion was followed at irregular interval. Of 5 blood recipients, Hepatitis C virus was detected in 2 patients (40%) and Anti-HCV antibody was detected in 2 patients (40%). We suppose that in contrast to disease group (Non A non B hepatitis), the possibility of viremia in the anti-HCV positive blood donors is significantly low and the character of those antibody may be convalescent antibody after hepatitis C resolution. (Author).

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)

Improved quantification of a commercial enzyme-linked immunosorbent assay kit for measuring anti-MDA5 antibody.

Science.gov (United States)

Gono, Takahisa; Okazaki, Yuka; Murakami, Akihiro; Kuwana, Masataka

2018-04-09

To compare the quantitative performance for measuring anti-MDA5 antibody titer of two enzyme-linked immunosorbent assay (ELISA) systems: an in-house ELISA and the commercial MESACUP TM anti-MDA5 test. Anti-MDA5 antibody titer was measured in sera from 70 patients with dermatomyositis using an in-house ELISA and the MESACUP TM anti-MDA5 test side-by-side. For the commercial ELISA kit, serum samples diluted 1:101 were used according to the manufacturer's protocol, but serial dilutions of sera were also examined to identify the optimal serum dilution for quantification. The anti-MDA5 antibody titers measured by the in-house and commercial ELISAs were positively correlated with each other (r = 0.53, p = .0001), but the antibody titer measured by the commercial ELISA was less sensitive to change after medical treatment, and 37 (80%) of 46 anti-MDA5-positive sera had antibody titer exceeding the quantification range specified by the manufacturer (≥150 index). Experiments using diluted serum samples revealed that diluting the sera 1:5050 improved the quantitative performance of the MESACUP TM anti-MDA5 test, including a better correlation with the in-house ELISA results and an increased sensitivity to change. We improved the ability of the commercial ELISA kit to quantify anti-MDA5 antibody titer by altering its protocol.

Anti-ribosomal P antibodies related to depression in early clinical course of systemic lupus erythematosus

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Mansoor Karimifar

2013-01-01

Full Text Available Background: Diagnosis and treatment of neuropsychiatric lupus is still a major challenge in clinical practice. We investigated the association between depression and anti-ribosomal P (anti-P antibodies in a sample of Iranian patients with systemic lupus erythematosus (SLE. Materials and Methods: This cross-sectional study was conducted on adult patients with SLE referring to a referral out-patient clinic of rheumatology. Demographic data and clinical data with regards to measuring disease activity with the systemic lupus erythematosus disease activity index were gathered. Anti-P antibodies were measured with the enzyme-linked immunosorbent assay method. Depression severity was measured by the Beck Depression Inventory-II. Results: One hundred patients (80% female and 20% male, age = 34.8 ± 10.9 years were included. Anti-P antibodies were present more frequently in depressed than non-depressed patients (30% vs. 10%, P = 0.015. Depression severity was correlated with anti-P antibodies level only in patients with disease duration of less than 2 years (r = 0.517, P = 0.019. There was no association between the depression severity and disease activity. Binary logistic regression analysis showed age (B = 0.953, CI 95%: 0.914-0.993 and positive anti-P antibodies (B = 4.30, CI 95%: 1.18-15.59 as factors that independently associated with depression. Conclusion: We found an association between depression and presence of anti-P antibodies, and also strong correlation between depression severity and anti-P antibodies level in newly diagnosed SLE patients. Depression severity in newly diagnosed SLE patients may reflect a neuropsychiatric involvement, and in later phases, it is more affected by the chronicity of the disease as well as other environmental factors.

Donor-specific Anti-HLA antibodies in allogeneic hematopoietic stem cell transplantation

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Sarah Morin-Zorman

2016-08-01

Full Text Available Allogeneic Hematopoietic Stem Cell Transplantation (AHSCT is a curative treatment for a wide variety of hematological diseases. In 30% of the cases, a geno-identical donor is available. Any other situation displays some level of Human Leukocyte Antigen (HLA incompatibility between donor and recipient. Deleterious effects of anti-HLA immunization have long been recognized in solid organ transplant recipients. More recently, anti-HLA immunization was shown to increase the risk of Primary Graft Failure (PGF, a severe complication of AHSCT that occurs in 3 to 4% of matched unrelated donor transplantation and up to 15% in cord blood transplantation and T-cell depleted haplo-identical stem cell transplantation. Rates of PGF in patients with DSA were reported to be between 24 to 83% with the highest rates in haplo-identical and cord blood transplantation recipients. This led to the recommendation of anti-HLA antibody screening to detect Donor Specific Antibodies (DSA in recipients prior to AHSCT. In this review, we highlight the role of anti-HLA antibodies in AHSCT and the mechanisms that may lead to PGF in patients with DSA, and discuss current issues in the field.

The prevalence of ANA antibodies, anticentromere antibodies, and anti-cyclic citrullinated peptide antibodies in patients with primary Sjögren’s syndrome compared to patients with dryness symptoms without primary Sjögren’s syndrome confirmation

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Maria Maślińska

2017-07-01

Full Text Available Objectives : Our study analyses the prevalence of ANA, anti-SS-A, anti-SS-B, and ACA and ACPA antibodies in patients with pSS and with dryness symptoms without pSS confirmation, and the association of ACPA and ACA antibodies with specific clinical symptoms. Materials and methods : 113 patients were divided into two groups: I – with diagnosed pSS (N = 75; and II – with dryness without pSS evidence (N = 38. Diagnostics: indirect immunofluorescence (IF; Hep-2 cell line of antinuclear antibodies (ANA, anti-SS-A anti-SS-B antibodies determined with semi-quantitative method, autoantibody profile (14 antigens, ANA Profil 3 EUROLINE; basic laboratory, ophthalmic examination tests, minor salivary gland biopsy with focus score (FS, joint and lung evaluation, and ESSDAI questionnaire (pSS activity. Results : 88% of group I had ANA antibodies (1 : 320 titre, 5.3% at 1 : 160. Anti-SS-A antibodies were present in 88% of group I, including all ANA 1 : 160. Anti-SS-A antibodies positively correlated with greater and moderate activity of ESSDAI 5 (p = 0.046 and FS. The presence of SS-B antibodies significantly affected disease activity. ACPA present: group I – 13% (associated with higher arthritis incidence; p = 0.003; group II – 8%. ACA antibodies present in 4% of group I, but not in group II. No ACA association with interstitial lung changes (small ACA + group excludes full conclusions. Conclusions : ANA antibodies should also be considered in a titre of less than 1 : 320, but the presence of anti-SS-A antibodies is still the most important immunological marker for pSS. Anti-SS-A antibodies correlate with higher disease activity (ESSDAI ≥ 5 and higher FS. The presence of the anti-SS-B antibody was significantly affected by higher activity of the disease. The incidence of arthritis was higher in patients with ACPA+ pSS compared to ACPA– (p = 0.003. There was no relationship between ACPA and arthritis in patients with dry-type syndrome without

The role of B cell-mediated T cell costimulation in the efficacy of the T cell retargeting bispecific antibody BIS20x3

NARCIS (Netherlands)

Stel, AJ; Kroesen, BJ; Jacobs, Susan; Groen, H; de Leij, LFMH; Kluin-Nelemans, HC; Withoff, S

2004-01-01

In this study, we investigated the role of the naturally occurring B cell-mediated T cell costimulation in the antitumor efficacy of the bispecific Ab BIS20x3. BIS20x3 has a dual specificity for both CD20 and CD3 and has previously been shown to effectively direct the lytic potential of cytolytic T

Pre- and Posttransplant IgA Anti-Fab Antibodies to Predict Long-term Kidney Graft Survival.

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Amirzargar, M A; Amirzargar, A; Basiri, A; Hajilooi, M; Roshanaei, G; Rajabi, G; Solgi, G

2015-05-01

Immunologic factors are reliable markers for allograft monitoring, because of their seminal role in rejection process. One of these factors is the immunoglobulin (Ig)A anti-Fab of the IgG antibody. This study aimed to evaluate the predictive value of pre- and posttransplant levels of this marker for kidney allograft function and survival. Sera samples of 59 living unrelated donor kidney recipients were collected before and after transplantation (days 7, 14, and 30) and investigated for IgA anti-Fab of IgG antibody levels using enzyme-linked immunosorbent assay in relation with allograft outcome. Among 59 patients, 15 cases (25%) including 10 with acute rejection and 5 with chronic rejection episodes showed graft failure during a mean of 5 years of follow-up. High posttransplant levels of IgA anti-Fab antibodies were observed more frequently in patients with stable graft function (SGF) compared with patients with graft failure (P = 2 × 10(-6)). None of patients with acute or chronic rejection episodes had high levels of IgA anti-Fab antibodies at day 30 posttransplant compared with the SGF group (P = 10(-6) and P = .01, respectively). In addition, high levels of IgA anti-Fab antibody correlated with lesser concentration of serum creatinine at 1 month posttransplantation (P = .01). Five-year graft survival was associated with high levels of pre- and posttransplant IgA anti-Fab antibodies (P = .02 and P = .003, respectively). Our findings indicate the protective effect of higher levels of IgA anti-Fab antibodies regarding to kidney allograft outcomes and long-term graft survival. Copyright © 2015 Elsevier Inc. All rights reserved.

Reactivity of eleven anti-human leucocyte monoclonal antibodies with lymphocytes from several domestic animals

DEFF Research Database (Denmark)

Aasted, Bent; Blixenkrone-Møller, Merete; Larsen, Else Bang

1988-01-01

Nine commercially available monoclonal antibodies and two monoclonal antibodies from The American Type Culture Collection, raised against various human leucocyte surface antigens, were tested on lymphocytes from cow, sheep, goat, swine, horse, cat, dog, mink, and rabbit as well as man. Four...... antibodies bound to lymphocytes from some of the animals. These were the antibodies against CD8 and CD4 antigen, the antibody to C3b-receptor, and the antibody to the HLA-DR antigen. The CD8 antigen-reactive antibody reacted with lymphocytes from mink, cat, dog, and sheep, while the CD4 antigen......-reactive antibody reacted with lymphocytes from mink. The anti-C3b-R antibody reacted with lymphocytes from horse, swine, dog, and cat, and the anti-HLA-DR reacted with lymphocytes from cow, goat, sheep, horse, dog, cat, and mink....

Anti-phosphatidylserine/prothrombin antibodies: an additional diagnostic marker for APS?

Science.gov (United States)

Pregnolato, Francesca; Chighizola, Cecilia B; Encabo, Susan; Shums, Zakera; Norman, Gary L; Tripodi, Armando; Chantarangkul, Veena; Bertero, Tiziana; De Micheli, Valeria; Borghi, Maria Orietta; Meroni, Pier Luigi

2013-07-01

Among the diagnostic assays for anti-phospholipid syndrome (APS), lupus anticoagulant (LA) is the strongest predictor of thrombosis; however, it presents several limitations as interference with anticoagulant therapy and poor inter-laboratory agreement. Two-thirds of LA activity is apparently due to antibodies against prothrombin (PT), usually detectable by ELISA. Binding of PT to phosphatidylserine (PS) has been shown to enhance solid-phase anti-PT assay sensitivity. To determine the prevalence of antibodies against PS/PT (aPS/PT) in APS, we tested the semiquantitative QUANTA Lite(®) aPS/PT ELISA in a cohort of 80 APS patients. The prevalence of aPS/PT was 81.3%, rising to 87.6% when considering LA-positive subjects only. We observed a strong correlation between aPS/PT and LA (p = 0.006). To note, APS patients with thrombotic manifestations displayed significantly higher IgG aPS/PT titers compared to 20 aPL asymptomatic carriers (p = 0.012). To rule out a possible cross-reactivity of anti-β2 glycoprotein I antibodies (aβ2GPI) with PS/PT complex, we tested two monoclonal aβ2GPI antibodies and an affinity-purified (AP) polyclonal aβ2GPI IgG obtained from the serum of a patient reacting against both β2GPI and PS/PT. The two monoclonal antibodies did not show any reactivity against PS/PT complex, similarly the AP IgGs did not react toward PS/PT antigen while preserved their aβ2GPI activity. Our findings suggest that aPS/PT are a definite antibody population in APS. Moreover, the good correlation between aPS/PT ELISA and LA may support its use as a surrogate test for LA, particularly useful to overcome the technical limitations of the functional assay.

Autoimmune severe hypertriglyceridemia induced by anti-apolipoprotein C-II antibody.

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Yamamoto, Hiroyasu; Tanaka, Minoru; Yoshiga, Satomi; Funahashi, Tohru; Shimomura, Iichiro; Kihara, Shinji

2014-05-01

Among type V hyperlipoproteinemias, only one-fourth of the patients have genetic defects in lipoprotein lipase (LPL) or in its associated molecules; the exact mechanism in other patients is usually unknown. The aim of the study was to report a case of severe hypertriglyceridemia induced by anti-apolipoprotein (apo) C-II autoantibody and to clarify its pathogenesis. A 29-year-old Japanese woman presented with severe persistent hypertriglyceridemia since the age of 20 years. The past history was negative for acute pancreatitis, eruptive xanthomas, or lipemia retinalis. LPL mass and activities were normal. Plasma apo C-II levels were extremely low, but no mutation was observed in APOC2. Apo C-II protein was detected in the serum by immunoprecipitation and Western blotting. Large amounts of IgG and IgM were incorporated with apo C-II protein coimmunoprecipitated by anti-apo C-II antibody. IgG, but not IgM, purified from the serum prevented interaction of apo C-II with lipid substrate and diminished LPL hydrolysis activity. We identified anti-apo C-II antibody in a myeloma-unrelated severe hypertriglyceridemic patient. In vitro analysis confirmed that the autoantibody disrupted the interaction between apo C-II and lipid substrate, suggesting the etiological role of anti-apo C-II antibody in severe hypertriglyceridemia in this patient.

Arthritis is inhibited in Borrelia-primed and infected interleukin-17A-deficient mice after administration of anti-gamma-interferon, anti-tumor necrosis factor alpha and anti-interleukin-6 antibodies.

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Kuo, Joseph; Warner, Thomas F; Schell, Ronald F

2017-08-31

The role that cytokines play in the induction of Lyme arthritis is gradually being delineated. We showed previously that severe arthritis developed in a T-cell-driven murine model, even in mice lacking interleukin-17A (IL-17A) and administered anti-gamma-interferon (IFN-γ) antibody. Increased levels of tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6), two pro-inflammatory cytokines, were detected in cultures of popliteal lymph node cells obtained from these mice. We hypothesized that concomitantly administered anti-IL-6, anti-TNF-α and anti-IFN-γ antibodies would inhibit the development of arthritis in IL-17A-deficient mice. Our results showed that swelling of the hind paws and histopathological changes consistent with arthritis were significantly reduced in IL-17A-deficient mice that administered the three anti-cytokine antibodies. These results suggest that treatment with multiple anti-cytokine antibodies can abrogate the induction of Lyme arthritis in mice. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Characterization of a purified nicotinic receptor from rat brain by using idiotypic and anti-idiotypic antibodies

International Nuclear Information System (INIS)

Abood, L.G.; Langone, J.J.; Bjercke, R.; Lu, X.; Banerjee, S.

1987-01-01

The availability of an anti-nicotine monoclonal antibody has made it possible to further establish the nature of the nicotine recognition proteins purified from rat brain by affinity chromatography and to provide a highly sensitive assay for determining [ 3 H]nicotine binding to the purified material. An enantiomeric analogue of nicotine. (-)-6-hydroxymethylnicotine, was used to prepare the affinity column. In addition, with the use of an anti-idiotypic monoclonal antibody, it was confirmed that the recognition site for nicotine resides on a protein complex composed of two components with molecular masses of 62 and 57 kDa. It was also demonstrated that the same two proteins could be purified by immunoaffinity chromatography with the use of an anti-idiotypic monoclonal antibody. With the use of the anti-nicotine antibody to measure [ 3 H]nicotine binding, the purified material was shown to bind 250 pmol/mg of protein. By utilizing a procedure in which the purified receptor protein was conjugated to membranes by disulfide bonds, a binding activity of 80 pmol/mg was obtained. With the availability of sterospecific monoclonal antibodies to (-)-nicotine as well as monoclonal anti-idiotypic antibodies derived when the anti-nicotine antibodies were used as immunogens, additional procedures became available for the further characterization of the purified nicotine receptor and examining its (-)-[ 3 H]nicotine-binding characteristics

Design and Pharmacokinetic Characterization of Novel Antibody Formats for Ocular Therapeutics.

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Gadkar, Kapil; Pastuskovas, Cinthia V; Le Couter, Jennifer E; Elliott, J Michael; Zhang, Jianhuan; Lee, Chingwei V; Sanowar, Sarah; Fuh, Germaine; Kim, Hok Seon; Lombana, T Noelle; Spiess, Christoph; Nakamura, Makia; Hass, Phil; Shatz, Whitney; Meng, Y Gloria; Scheer, Justin M

2015-08-01

To design and select the next generation of ocular therapeutics, we performed a comprehensive ocular and systemic pharmacokinetic (PK) analysis of a variety of antibodies and antibody fragments, including a novel-designed bispecific antibody. Molecules were administrated via intravitreal (IVT) or intravenous (IV) injections in rabbits, and antibody concentrations in each tissue were determined by ELISA. A novel mathematical model was developed to quantitate the structure-PK relationship. After IVT injection, differences in vitreal half-life observed across all molecules ranged between 3.2 and 5.2 days. Modification or elimination of the fragment crystallizable (Fc) region reduced serum half-life from 9 days for the IgG to 5 days for the neonatal Fc receptor (FcRn) null mAb, to 3.1 to 3.4 days for the other formats. The F(ab')2 was the optimal format for ocular therapeutics with comparable vitreal half-life to full-length antibodies, but with minimized systemic exposure. Concomitantly, the consistency among mathematical model predictions and observed data validated the model for future PK predictions. In addition, we showed a novel design to develop bispecific antibodies, here with activity targeting multiple angiogenesis pathways. We demonstrated that protein molecular weight and Fc region do not play a critical role in ocular PK, as they do systemically. Moreover, the mathematical model supports the selection of the "ideal therapeutic" by predicting ocular and systemic PK of any antibody format for any dose regimen. These findings have important implications for the design and selection of ocular therapeutics according to treatment needs, such as maximizing ocular half-life and minimizing systemic exposure.

The effect of prior transfusion history on blood donor anti-hepatitis C virus antibody.

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Mazda, T; Nakata, K; Ota, K; Kaminuma, Y; Katayama, T

1993-01-01

In Japan, the major transfusion-associated disease is non-A, non-B hepatitis. We studied the relationship between transfusion history and blood donor antibodies to hepatitis C virus (HCV). The positive rate of antibodies to the HCV nonstructural protein (c100-3) depended on age and the time elapsed since transfusion. The anti-c100-3 ratio for subjects with transfusions made prior to 20 years ago was high. One quarter century ago, a change occurred in national blood policy from paid to non-paid voluntary donations. We also have studied the anti-HCV positive rate among donors with prior transfusion using a second generation HCV test kit which includes anti-HCV core antibody detection. The anti-HCV positive rate for the second generation test was higher than that for the anti-c100-3 test. Introduction of the second generation test is therefore more useful in screening than the anti-c100-3 test for blood programs.

Doxorubicin-anti-carcinoembryonic antigen immunoconjugate activity in vitro.

Science.gov (United States)

Richardson, V J; Ford, C H; Tsaltas, G; Gallant, M E

1989-04-01

An in vitro model consisting of a series of 11 human cancer cell lines with varying density of expression of membrane carcinoembryonic antigen (CEA) has been used to evaluate conjugates of doxorubicin (Adriamycin) covalently linked by a carbodiimide method to goat polyclonal antibodies and mouse monoclonal antibodies to CEA. Conjugates were produced which retained both antigen binding and drug cytotoxicity. IC50 values were determined for free drug, free drug mixed with unconjugated antibodies and for the immunoconjugates. Cell lines that were very sensitive to free drug (IC50 less than 100 ng/ml) were also found to be highly sensitive to conjugated drug and similarly cell lines resistant to drug (IC50 greater than 1,000 ng/ml) were also resistant to conjugated drug. Although there was no correlation between CEA expression and conjugates efficacy, competitive inhibition studies using autologous antibody to block conjugate binding to cells indicated immunoconjugates specificity for the CEA target.

Radionuclide-Based Cancer Imaging Targeting the Carcinoembryonic Antigen

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Hao Hong

2008-01-01

Full Text Available Carcinoembryonic antigen (CEA, highly expressed in many cancer types, is an important target for cancer diagnosis and therapy. Radionuclide-based imaging techniques (gamma camera, single photon emission computed tomography [SPECT] and positron emission tomography [PET] have been extensively explored for CEA-targeted cancer imaging both preclinically and clinically. Briefly, these studies can be divided into three major categories: antibody-based, antibody fragment-based and pretargeted imaging. Radiolabeled anti-CEA antibodies, reported the earliest among the three categories, typically gave suboptimal tumor contrast due to the prolonged circulation life time of intact antibodies. Subsequently, a number of engineered anti-CEA antibody fragments (e.g. Fab’, scFv, minibody, diabody and scFv-Fc have been labeled with a variety of radioisotopes for CEA imaging, many of which have entered clinical investigation. CEA-Scan (a 99mTc-labeled anti-CEA Fab’ fragment has already been approved by the United States Food and Drug Administration for cancer imaging. Meanwhile, pretargeting strategies have also been developed for CEA imaging which can give much better tumor contrast than the other two methods, if the system is designed properly. In this review article, we will summarize the current state-of-the-art of radionuclide-based cancer imaging targeting CEA. Generally, isotopes with short half-lives (e.g. 18F and 99mTc are more suitable for labeling small engineered antibody fragments while the isotopes with longer half-lives (e.g. 123I and 111In are needed for antibody labeling to match its relatively long circulation half-life. With further improvement in tumor targeting efficacy and radiolabeling strategies, novel CEA-targeted agents may play an important role in cancer patient management, paving the way to “personalized medicine”.

Report of two cases of anti-M antibody in antenatal patients

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Joseph Philip

2015-01-01

Full Text Available Anti-M is a relatively common naturally occurring antibody reacting optimally at 4°C and weakly or nonreactive at 37°C. It is usually clinically insignificant but can be active at 37°C because of thermal amplitude of IgM component or presence of IgG component. It can cause or delayed hemolytic transfusion reactions or hemolytic disease of newborn. At our center we have encountered two cases of anti-M antibodies- one presenting as crossmatch incompatibility and other as blood grouping discrepancy in the last 8 months.

Human anti-rhesus D IgG1 antibody produced in transgenic plants

DEFF Research Database (Denmark)

Bouquin, Thomas; Thomsen, Mads; Nielsen, Leif Kofoed

2002-01-01

antigen, which is responsible for alloimmunization of RhD- mothers carrying an RhD+ fetus. Anti-RhD extracted from plants specifically reacted with RhD+ cells in antiglobulin technique, and elicited a respiratory burst in human peripheral blood mononuclear cells. Plant-derived antibody had equivalent......Transgenic plants represent an alternative to cell culture systems for producing cheap and safe antibodies for diagnostic and therapeutic use. To evaluate the functional properties of a 'plantibody', we generated transgenic Arabidopsis plants expressing full-length human IgG1 against the Rhesus D...... properties to CHO cell-produced anti-RhD antibody, indicating its potential usefulness in diagnostic and therapeutic programs....

Clinical significance of serum anti-human papillomavirus 16 and 18 antibodies in cervical neoplasia.

Science.gov (United States)

Chay, Doo Byung; Cho, Hanbyoul; Kim, Bo Wook; Kang, Eun Suk; Song, Eunseop; Kim, Jae-Hoon

2013-02-01

To estimate the clinical significance of serum anti-human papillomavirus (HPV) antibodies and high-risk cervical HPV DNA in cervical neoplasia. The study population comprised patients who were histopathologically diagnosed with cervical intraepithelial neoplasia (CIN) 1 (n=64), CIN 2 and 3 (n=241), cervical cancer (n=170), and normal control participants (n=975). Cervical HPV DNA tests were performed through nucleic acid hybridization assay tests, and serum anti-HPV 16 and 18 antibodies were measured by competitive immunoassay. The associations of HPV DNA and anti-HPV antibodies were evaluated with demographic characteristics and compared according to the levels of disease severity. Anti-HPV antibodies were also investigated with clinicopathologic parameters, including survival data. Among various demographic characteristics, factors involving sexual behavior had a higher tendency of HPV DNA positivity and HPV seropositivity. Human papillomavirus DNA mean titer and positivity were both increased in patients with cervical neoplasia compared with those with normal control participants, but there was no statistical difference among types of cervical neoplasia. Serum anti-HPV 16 antibodies were also able to differentiate cervical neoplasia from a normal control participant and furthermore distinguished CIN 1 from CIN 2 and 3 (odd ratio 2.87 [1.43-5.78], P=.002). In cervical cancer, HPV 16 seropositivity was associated with prolonged disease-free survival according to the univariable analysis (hazard ratio=0.12 [0.01-0.94], P=.044). Serum anti-HPV 16 antibodies can distinguish cervical neoplasia from a normal control and has the advantage of identifying high-grade CIN. Moreover, in cervical cancer, HPV 16 seropositivity may be associated with a more favorable prognosis. II.

The Anti-Acetylcholine Receptor Antibody Test in Suspected Ocular Myasthenia Gravis

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Jung Jin Lee

2014-01-01

Full Text Available Aim. To estimate the clinical significance of anti-acetylcholine receptor antibody (anti-AChR-Ab levels in suspected ocular myasthenia gravis. Methods. In total, 144 patients complaining of fluctuating diplopia and ptosis were evaluated for serum levels of anti-acetylcholine receptor antibody and their medical charts were retrospectively reviewed. Subjects were classified into three groups: variable diplopia only, ptosis only, and both variable diplopia and ptosis. We investigated serum anti-AChR-Ab titer levels and performed thyroid autoantibody tests. Results. Patients’ chief complaints were diplopia (N=103, ptosis (N=12, and their concurrence (N=29. Abnormal anti-AChR-Ab was observed in 21 of 144 patients (14.1%. Between the three groups, mean age, number of seropositive patients, and mean anti-AChR-Ab level were not significantly different (P=0.224, 0.073, and 0.062, resp.. Overall, 27.5% of patients had abnormal thyroid autoantibodies. Conclusion. The sensitivity of anti-AChR-Ab was 14.1% in suspected ocular myasthenia gravis and seropositivity in myasthenia gravis patients showed a high correlation with the presence of thyroid autoantibodies.

Analysis of anti-HLA antibodies in sensitized kidney transplant candidates subjected to desensitization with intravenous immunoglobulin and rituximab.

Science.gov (United States)

Lobashevsky, Andrew L; Higgins, Nancy G; Rosner, Kevin M; Mujtaba, Muhammad A; Goggins, William C; Taber, Tim E

2013-07-27

Preexisting donor-specific antibodies against human leukocyte antigens are major risk factors for acute antibody-mediated and chronic rejection of kidney transplant grafts. Immunomodulation (desensitization) protocols may reduce antibody concentration and improve the success of transplant. We investigated the effect of desensitization with intravenous immunoglobulin and rituximab on the antibody profile in highly sensitized kidney transplant candidates. In 31 transplant candidates (calculated panel-reactive antibody [cPRA], 34%-99%), desensitization included intravenous immunoglobulin on days 0 and 30 and a single dose of rituximab on day 15. Anti-human leukocyte antigen antibodies were analyzed before and after desensitization. Reduction of cPRA from 25% to 50% was noted for anti-class I (5 patients, within 20-60 days) and anti-class II (3 patients, within 10-20 days) antibodies. After initial reduction of cPRA, the cPRA increased within 120 days. In 24 patients, decrease in mean fluorescence intensity of antibodies by more than 50% was noted at follow-up, but there was no reduction of cPRA. Rebound occurred in 65% patients for anti-class I antibodies at 350 days and anti-class II antibodies at 101 to 200 days. Probability of rebound effect was higher in patients with mean fluorescence intensity of more than 10,700 before desensitization, anti-class II antibodies, and history of previous transplant. The desensitization protocol had limited efficacy in highly sensitized kidney transplant candidate because of the short period with antibody reduction and high frequency of rebound effect.

An Adult Case of Recurrent Guillain-Barré Syndrome with Anti-galactocerebroside Antibodies

Science.gov (United States)

Takahashi, Hisashi; Kimura, Tadashi; Yuki, Natsuko; Yoshioka, Akira

2017-01-01

A 79-year-old woman with a history of Guillain-Barré syndrome (GBS) developed somnolence and tetraparesis after pneumonia. Based on clinical and laboratory findings, she was diagnosed with complications of acute inflammatory demyelinating polyneuropathy (AIDP) and acute disseminated encephalomyelitis (ADEM). Anti-galactocerebroside (Gal-C) IgG antibodies were detected in her serum. Cases of recurrent GBS in patients who are positive for this antibody are extremely rare. The anti-Gal-C IgG antibodies likely played an important role in the pathogenesis of the AIDP and ADEM. PMID:29093388

ELISA with double antigen sandwich for screening specific serum anti-TP antibody in blood donors

International Nuclear Information System (INIS)

Wang Yiqing; Shi Zhixu

2002-01-01

Objective: To select a sensitive and specific laboratory examination suitable for screening serum anti-TP antibody in blood donors. Methods: The serum anti-TP antibody in 11271 blood donors were detected using ELISA with double antigen sandwich and the outcomes were compared with those using RPR assay. The conflicting specimen were confirmed by repeating the test with TPHA assay. Results: The positive rates of serum anti-TP antibody by ELISA with double antigen sandwich and RPR was 0.36% (41/11271) and 0.26% (29/11271), respectively. The coincidence of the detecting outcomes by ELISA with double antigen sandwich and RPR with TPHA was 97.5% (40/41) and 63.41%(26/41) respectively. Conclusion: Compared with RPR assay, ELISA with double antigen sandwich has higher sensibility and specificity for screening serum anti-TP antibody in blood donors

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.

Function-blocking antibodies to human vascular adhesion protein-1: a potential anti-inflammatory therapy.

Science.gov (United States)

Kirton, Christopher M; Laukkanen, Marja-Leena; Nieminen, Antti; Merinen, Marika; Stolen, Craig M; Armour, Kathryn; Smith, David J; Salmi, Marko; Jalkanen, Sirpa; Clark, Michael R

2005-11-01

Human vascular adhesion protein-1 (VAP-1) is a homodimeric 170-kDa sialoglycoprotein that is expressed on the surface of endothelial cells and functions as a semicarbazide-sensitive amine oxidase and as an adhesion molecule. Blockade of VAP-1 has been shown to reduce leukocyte adhesion and transmigration in in vivo and in vitro models, suggesting that VAP-1 is a potential target for anti-inflammatory therapy. In this study we have constructed mouse-human chimeric antibodies by genetic engineering in order to circumvent the potential problems involved in using murine antibodies in man. Our chimeric anti-VAP-1 antibodies, which were designed to lack Fc-dependent effector functions, bound specifically to cell surface-expressed recombinant human VAP-1 and recognized VAP-1 in different cell types in tonsil. Furthermore, the chimeric antibodies prevented leukocyte adhesion and transmigration in vitro and in vivo. Hence, these chimeric antibodies have the potential to be used as a new anti-inflammatory therapy.

Anti-soluble liver antigen/liver-pancreas (SLA/LP) antibodies in pediatric patients with autoimmune hepatitis.

Science.gov (United States)

Vitozzi, Susana; Djilali-Saiah, Idriss; Lapierre, Pascal; Alvarez, Fernando

2002-12-01

Antibodies against soluble liver antigen/liver-pancreas (SLA/LP) have been associated with severe autoimmune hepatitis (AIH) and poor outcome, but most of these reports have focused on adult patients. The aim of this study was to assess the prevalence and clinical significance of anti-SLA/LP antibodies in a pediatric population with AIH. We developed a quantitative enzyme-linked immunoassay (ELISA), a Western blot (WB) and an immunoprecipitation assay (IPA) based on recombinant cDNA from activated Jurkat cells. The specificity of these tests was validated by testing 200 serum samples from healthy subjects, and from patients with liver and non-liver diseases. Anti-SLA/LP antibodies were found in patients with type 1 and type 2 AIH. The prevalence of these antibodies in patients with type 1 AIH was: 42% when tested by ELISA, 15% by WB and 50% by IPA. In patients with type 2 AIH, the prevalence rates were 42% by ELISA, 18% by WB and 44% by IPA. The mean titer values for anti-SLA/LP antibodies was significantly higher in type 2 AIH (1:1,300 +/- 339) than in type 1 AIH (1:600 +/- 71; p LKM1) and anti-liver cytosol type 1 (LC1) antibodies in sera. The presence of anti-SLA/LP showed a significant female preponderance in type 1 and 2 AIH patients (p = 0.0003 and p = 0.003, respectively), and was significantly correlated with a lower age at diagnosis (p = 0.05) in type 1 AIH patients. In conclusion, anti-SLA/LP antibodies in pediatric patients are associated with both type 1 and 2 AIH.

Generation of anti-idiotype antibodies for application in clinical immunotherapy laboratory analyses.

Science.gov (United States)

Liu, Zhanqi; Panousis, Con; Smyth, Fiona E; Murphy, Roger; Wirth, Veronika; Cartwright, Glenn; Johns, Terrance G; Scott, Andrew M

2003-08-01

The chimeric monoclonal antibody ch806 specifically targets the tumor-associated mutant epidermal growth factor receptor (de 2-7EGFR or EGFRVIII) and is currently under investigation for its potential use in cancer therapy. The humanised monoclonal antibody hu3S193 specifically targets the Lewis Y epithelial antigen and is currently in Phase I clinical trials in patients with advanced breast, colon, and ovarian carcinomas. To assist the clinical evaluation of ch806 and hu3S193, laboratory assays are required to monitor their serum pharmacokinetics and quantitate any immune responses to the antibodies. Mice immunized with ch806 or hu3S193 were used to generate hybridomas producing antibodies with specific binding to ch806 or hu3S193 and competitive for antigen binding. These anti-idiotype antibodies (designated Ludwig Melbourne Hybridomas, LMH) were investigated as reagents suitable for use as positive controls for HAHA or HACA analyses and for measuring hu3S193 or ch806 in human serum. Anti-idiotypes with the ability to concurrently bind two target antibody molecules were identified, which enabled the development of highly reproducible, sensitive, specific ELISA assays for determining serum concentrations of hu3S193 and ch806 with a 3 ng/mL limit of quantitation using LMH-3 and LMH-12, respectively. BIAcore analyses determined high apparent binding affinity for both idiotypes: LMH-3 binding immobilized hu3S193, Ka = 4.76 x 10(8) M(-1); LMH-12 binding immobilised ch806, Ka = 1.74 x 10(9) M(-1). Establishment of HAHA or HACA analysis of sera samples using BIAcore was possible using LMH-3 and LMH-12 as positive controls for quantitation of immune responses to hu3S193 or ch806 in patient sera. These anti-idiotypes could also be used to study the penetrance and binding of ch806 or hu3S193 to tumor cells through immunohistochemical analysis of tumor biopsies. The generation of anti-idiotype antibodies capable of concurrently binding a target antibody on each variable

Anti-Annexin V Antibodies: Association with Vascular Involvement and Disease Outcome in Patients with Systemic Sclerosis

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Iman A. Hassan

2010-04-01

Full Text Available Background: Systemic Sclerosis (SSc is characterized by skin thickening, fibrosis and vascular obliteration. The onset and course are heterogeneous. Prominent features include autoimmunity, inflammation and vascular damage. Aim of study: To measure the level of serum Anti-Annexin V antibodies in SSc patients and to study its significance in relation to vascular damage in these patients. Patients and methods: Twenty patients with SSc (12 with diffuse SSc and 8 with the limited form and 10 healthy age and sex matched volunteers as controls were all subjected to routine laboratory testing and immunological profiling including antinuclear, anti-Scl-70, anticentomere, anticardiolipin antibodies and anti-annexin V antibodies titres. Vascular damage was assessed by clinical examination and assessment of the disease activity score, nailfold capillaroscopy and colour flow Doppler of the renal arteries; Doppler echocardiography was used for assessing pulmonary hypertension. Results: Anti-annexin V antibodies were detected in 75% of patients. Comparisons between anti-annexin V in diffuse and limited subgroups showed no significance; however a statistically significant positive correlation was found between Anti-annexin V titre and the degree of vascular damage in SSc patients. Anti-annexin V increased significantly in patients with severe vascular damage in comparison with those less affected (15.3 ± 6.6 vs. 11.25 ± 3.6, P , 0.05. A significant positive correlation was found between Anti-annexin V titre and both the ACL titre (r = 0.79, P , 0.001 and the resistive index of the main renal artery (r = 0.42, P , 0.05. Conclusion: Anti-annexin V antibodies were significantly present in sera of patients with SSc. Patients with more severe forms of vascular damage had higher titres of these antibodies. Anti-annexin V antibodies are a sensitive predictor of vascular damage in SSc and could serve as a useful parameter in discriminating patients with a higher

Anti-Annexin V Antibodies: Association with Vascular Involvement and Disease Outcome in Patients with Systemic Sclerosis

Directory of Open Access Journals (Sweden)

Reem A. Habeeb

2010-01-01

Full Text Available Background Systemic Sclerosis (SSc is characterized by skin thickening, fibrosis and vascular obliteration. The onset and course are heterogeneous. Prominent features include autoimmunity, inflammation and vascular damage. Aim of Study To measure the level of serum Anti-Annexin V antibodies in SSc patients and to study its significance in relation to vascular damage in these patients. Patients and Methods Twenty patients with SSc (12 with diffuse SSc and 8 with the limited form and 10 healthy age and sex matched volunteers as controls were all subjected to routine laboratory testing and immunological profiling including antinuclear, anti-Scl-70, anticentomere, anticardiolipin antibodies and anti-annexin V antibodies titres. Vascular damage was assessed by clinical examination and assessment of the disease activity score, nailfold capillaroscopy and colour flow Doppler of the renal arteries; Doppler echocardiography was used for assessing pulmonary hypertension. Results Anti-annexin V antibodies were detected in 75% of patients. Comparisons between anti-annexin V in diffuse and limited subgroups showed no significance; however a statistically significant positive correlation was found between Anti-annexin V titre and the degree of vascular damage in SSc patients. Anti-annexin V increased significantly in patients with severe vascular damage in comparison with those less affected (15.3 ± 6.6 vs. 11.25 ± 3.6, P < 0.05. A significant positive correlation was found between Anti-annexin V titre and both the ACL titre (r = 0.79, P < 0.001 and the resistive index of the main renal artery (r = 0.42, P < 0.05. Conclusion Anti-annexin V antibodies were significantly present in sera of patients with SSc. Patients with more severe forms of vascular damage had higher titres of these antibodies. Anti-annexin V antibodies are a sensitive predictor of vascular damage in SSc and could serve as a useful parameter in discriminating patients with a higher risk of