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Sample records for anti-cd45 antibody labeled

  1. Durable donor engraftment after radioimmunotherapy using α-emitter astatine-211-labeled anti-CD45 antibody for conditioning in allogeneic hematopoietic cell transplantation.

    Science.gov (United States)

    Chen, Yun; Kornblit, Brian; Hamlin, Donald K; Sale, George E; Santos, Erlinda B; Wilbur, D Scott; Storer, Barry E; Storb, Rainer; Sandmaier, Brenda M

    2012-02-01

    To reduce toxicity associated with external γ-beam radiation, we investigated radioimmunotherapy with an anti-CD45 mAb labeled with the α-emitter, astatine-211 ((211)At), as a conditioning regimen in dog leukocyte antigen-identical hematopoietic cell transplantation (HCT). Dose-finding studies in 6 dogs treated with 100 to 618 μCi/kg (211)At-labeled anti-CD45 mAb (0.5 mg/kg) without HCT rescue demonstrated dose-dependent myelosuppression with subsequent autologous recovery, and transient liver toxicity in dogs treated with (211)At doses less than or equal to 405 μCi/kg. Higher doses of (211)At induced clinical liver failure. Subsequently, 8 dogs were conditioned with 155 to 625 μCi/kg (211)At-labeled anti-CD45 mAb (0.5 mg/kg) before HCT with dog leukocyte antigen-identical bone marrow followed by a short course of cyclosporine and mycophenolate mofetil immunosuppression. Neutropenia (1-146 cells/μL), lymphopenia (0-270 cells/μL), and thrombocytopenia (1500-6560 platelets/μL) with prompt recovery was observed. Seven dogs had long-term donor mononuclear cell chimerism (19%-58%), whereas 1 dog treated with the lowest (211)At dose (155 μCi/kg) had low donor mononuclear cell chimerism (5%). At the end of follow-up (18-53 weeks), only transient liver toxicity and no renal toxicity had been observed. In conclusion, conditioning with (211)At-labeled anti-CD45 mAb is safe and efficacious and provides a platform for future clinical trials of nonmyeloablative transplantation with radioimmunotherapy-based conditioning. PMID:22134165

  2. Bismuth 213-labeled anti-CD45 radioimmunoconjugate to condition dogs for nonmyeloablative allogeneic marrow grafts

    Energy Technology Data Exchange (ETDEWEB)

    Sandmaier, B M.(Fred Hutchinson Cancer Research Center, Seattle, WA); Bethge, W A.(Fred Hutchinson Cancer Research Center, Seattle, WA); Wilbur, D. Scott (Washington, Univ Of); Hamlin, Donald K.(Washington, Univ Of); Santos, E B.(Fred Hutchinson Cancer Research Center, Seattle, WA); Brechbiel, M W.(National Cancer Institute, National Institutes of Health, Bethesda, MD); Fisher, Darrell R.(BATTELLE (PACIFIC NW LAB)); Storb, R. (Fred Hutchinson Cancer Research Center)

    2002-01-01

    To lower treatment-related mortality and toxicity of conventional marrow transplantation, a nonmyeloablative regimen using 200 cGy total-body irradiation (TBI) and mycophenolate mofetil (MMF) combined with cyclosporine (CSP) for postgrafting immunosuppression was developed. To circumvent possible toxic effects of external- beam gamma irradiation, strategies for targeted radiation therapy were investigated. We tested whether the short-lived (46 minutes) alpha-emitter Bi-213 conjugated to an anti-CD45 monoclonal antibody (mAb) could replace 200 cGy TBI and selectively target hematopoietic tissues in a canine model of nonmyeloablative DLA-identical marrow transplantation. Biodistribution studies using iodine 123-labeled anti-CD45 mAb showed uptake in blood, marrow, lymph nodes, spleen, and liver. In a dose-escalation study, 7 dogs treated with the Bi-213-anti-CD45 conjugate (Bi-213 dose, 0.1-5.9 mCi/kg[3.7-218 MBq/kg]) without marrow grafts had no toxic effects other than a mild, reversible suppression of blood counts. On the basis of these studies, 3 dogs were treated with 0.5 mg/kg Bi-213-labeled anti-CD45 mAb (Bi-213 doses, 3.6, 4.6, and 8.8 mCi/kg[133, 170, and 326 MBq/kg]) given in 6 injections 3 and 2 days before grafting of marrow from DLA-identical littermates. The dogs also received MMF (10 mg/kg subcutaneously twice daily the day of transplantation until day 27 afterward) and CSP (15 mg/kg orally twice daily the day before transplantation until 35 days afterward). Therapy was well tolerated except for transient elevations in levels of transaminases in 3 dogs, followed by, in one dog, ascites. All dogs achieved prompt engraftment and stable mixed hematopoietic chimerism, with donor contributions ranging from 30% to 70% after more than 27 weeks of follow-up. These results form the basis for additional studies in animals and the design of clinical trials using Bi-213 as a nonmyeloablative conditioning regimen with minimal toxicity.

  3. Effects of Anti-CD45RB Monoclonal Antibody for T Lymphocyte Subsets in Mice Heart Transplantation Model.

    Science.gov (United States)

    Deng, C-Y; Wang, X-F; Qi, H; Li, F-R

    2016-08-01

    Anti-CD45RB monoclonal antibody (anti-CD45RBmAb), as a new immune tolerance inducer, may inhibit T cell proliferation and induce immune tolerance through competitive combination with CD45RB on the T cell surface, which blocks the conduction of activation signals. However, how anti-CD45RBmAb plays its role on T lymphocyte subsets during immunosuppression remains unclear. In this work, we investigate the effects of anti-CD45RBmAb on CD3(+) T lymphocyte both in vitro and in allogeneic heart transplant model in vivo. Interestingly, anti-CD45RBmAb could inhibit the proliferation of T cells, promote the transformation of T lymphocyte to Treg and Th2 cells, suppress the transformation to Th17 and Th1 cells, increase the number of Ts cells, decrease the number of Tm cells and thus play a role in immune inhibition and induction of immune tolerance. PMID:27146476

  4. 131I-Anti-CD45 Antibody Plus Busulfan and Cyclophosphamide before Allogeneic Hematophoietic Cell Transplantation for Treatment of Acute Myeloid Leukemia in First Remission

    Energy Technology Data Exchange (ETDEWEB)

    Pagel, John M.; Appelbaum, Frederick R.; Eary, Janet F.; Rajendran, Joseph G.; Fisher, Darrell R.; Gooley, Ted; Ruffner, Katherine; Nemecek, Eneida; Sickle, Eileen; Durack, Larry; Carreras, Jeanette; Horowitz, Mary; Press, Oliver W.; Gopal, Ajay K.; Martin, Paul J.; Bernstein, Irwin D.; Matthews, Dana C.

    2006-03-01

    In an attempt to improve outcomes for patients with acute myeloid leukemia (AML) after allogeneic hematopoietic cell transplantation (HCT), we conducted a Phase I/II study in which targeted irradiation delivered by 131I-anti-CD45 antibody was combined with targeted busulfan (BU; area-under-curve, 600-900 ng/ml) and cyclophosphamide (CY; 120 mg/kg). Fifty-two of 59 patients (88%) receiving a trace 131I-labeled dose of 0.5 mg/kg anti-CD45 murine antibody had higher estimated absorbed radiation in bone marrow and spleen than in any other organ. Forty-six patients were treated with 102-298 mCi 131I delivering an estimated 5.3-19 (mean 11.3) Gy to marrow, 17-72 (mean 29.7) Gy to spleen, and 3.5 Gy (n=4) to 5.25 Gy (n=42) to the liver. The estimated 3-year non-relapse mortality and disease-free survival (DFS) were 21% and 61%, respectively. These results were compared to those from 509 similar International Bone Marrow Transplant Registry patients transplanted using BU/CY alone. After adjusting for differences in age and cytogenetics-risk, the hazard of mortality among all antibody-treated patients was 0.65 times that of the Registry patients (95% CI 0.39-1.08; p=.09). The addition of targeted hematopoietic irradiation to conventional BU/CY is feasible and well tolerated, and Phase II results are sufficiently encouraging to warrant further study.

  5. 131I-Anti-CD45 Antibody Plus Busulfan and Cyclophosphamide before Allogeneic Hematophoietic Cell Transplantation for Treatment of Acute Myeloid Leukemia in First Remission

    International Nuclear Information System (INIS)

    In an attempt to improve outcomes for patients with acute myeloid leukemia (AML) after allogeneic hematopoietic cell transplantation (HCT), we conducted a Phase I/II study in which targeted irradiation delivered by 131I-anti-CD45 antibody was combined with targeted busulfan (BU; area-under-curve, 600-900 ng/ml) and cyclophosphamide (CY; 120 mg/kg). Fifty-two of 59 patients (88%) receiving a trace 131I-labeled dose of 0.5 mg/kg anti-CD45 murine antibody had higher estimated absorbed radiation in bone marrow and spleen than in any other organ. Forty-six patients were treated with 102-298 mCi 131I delivering an estimated 5.3-19 (mean 11.3) Gy to marrow, 17-72 (mean 29.7) Gy to spleen, and 3.5 Gy (n=4) to 5.25 Gy (n=42) to the liver. The estimated 3-year non-relapse mortality and disease-free survival (DFS) were 21% and 61%, respectively. These results were compared to those from 509 similar International Bone Marrow Transplant Registry patients transplanted using BU/CY alone. After adjusting for differences in age and cytogenetics-risk, the hazard of mortality among all antibody-treated patients was 0.65 times that of the Registry patients (95% CI 0.39-1.08; p=.09). The addition of targeted hematopoietic irradiation to conventional BU/CY is feasible and well tolerated, and Phase II results are sufficiently encouraging to warrant further study

  6. A Depleting Anti-CD45 Monoclonal Antibody as Isolated Conditioning for Bone Marrow Transplantation in the Rat.

    Directory of Open Access Journals (Sweden)

    Mark D Jäger

    Full Text Available A monoclonal antibody (mAb against the leukocyte common antigen CD45 (RT7 in rats could facilitate bone marrow transplantation (BMT. This study in rats evaluates a depletive rat anti-RT7a mAb as isolated tool for BMT conditioning without using irradiation or any chemotherapeutic / immunosuppressive agent.The model used a CD45 di-allelic polymorphism (RT7a/RT7b. The anti-RT7a mAb was intravenously administered to LEW.1W rats (RT1uRT7a at 5, 10 and 15 mg/kg. 1x108 BM cells of MHC syngeneic (RT1u, MHC disparate (RT1l or MHC haploidentical (RT1u/l donors were transplanted. All BM donor strains carried the RT7b allele so that their CD45+ cells were not affected by the anti-RT7a mAb. Recipients were monitored for reconstitution and donor-chimerism in blood leukocytes.mAb dosages of 5 or 10 mg/kg were myelosuppressive, whereas 15 mg/kg was myeloablative. Multi-lineage donor-chimerism at day 100 indicated engraftment of MHC syngeneic BM after any used mAb dosage (5 mg/kg: 46+/-7%; 10 mg/kg: 62+/-5%; 15 mg/kg: 80+/-4%. MHC disparate BM resulted in autologous reconstitution after conditioning by 10 mg/kg of the mAb and caused transient chimerism ending up in death associated with aplasia after conditioning by 15 mg/kg of the mAb. MHC haploidentical BM (F1 to parental engrafted only after conditioning by 15 mg/kg (chimerism at day 100: 78+/-7%. Abandonment of α/β TCR+ cell depletion from BM grafts impaired the engraftment process after conditioning using 15 mg/kg of the mAb in the MHC syngeneic setting (2 of 6 recipients failed to engraft and the MHC haploidentical setting (3 of 6 recipients failed.This depletive anti-RT7a mAb is myelosuppressive and conditions for engraftment of MHC syngeneic BM. The mAb also facilitates engraftment of MHC haploidentical BM, if a myeloablative dose is used. RT7b expressing, BM-seeded α/β TCR+ cells seem to impair the engraftment process after myeloablative mAb conditioning.

  7. A Depleting Anti-CD45 Monoclonal Antibody as Isolated Conditioning for Bone Marrow Transplantation in the Rat

    Science.gov (United States)

    Jäger, Mark D.; Vondran, Florian W. R.; Ramackers, Wolf; Röseler, Tilmann; Schlitt, Hans J.; Bektas, Hüseyin; Klempnauer, Jürgen; Timrott, Kai

    2016-01-01

    Objective A monoclonal antibody (mAb) against the leukocyte common antigen CD45 (RT7 in rats) could facilitate bone marrow transplantation (BMT). This study in rats evaluates a depletive rat anti-RT7a mAb as isolated tool for BMT conditioning without using irradiation or any chemotherapeutic / immunosuppressive agent. Methods The model used a CD45 di-allelic polymorphism (RT7a/RT7b). The anti-RT7a mAb was intravenously administered to LEW.1W rats (RT1uRT7a) at 5, 10 and 15 mg/kg. 1x108 BM cells of MHC syngeneic (RT1u), MHC disparate (RT1l) or MHC haploidentical (RT1u/l) donors were transplanted. All BM donor strains carried the RT7b allele so that their CD45+ cells were not affected by the anti-RT7a mAb. Recipients were monitored for reconstitution and donor-chimerism in blood leukocytes. Results mAb dosages of 5 or 10 mg/kg were myelosuppressive, whereas 15 mg/kg was myeloablative. Multi-lineage donor-chimerism at day 100 indicated engraftment of MHC syngeneic BM after any used mAb dosage (5 mg/kg: 46+/-7%; 10 mg/kg: 62+/-5%; 15 mg/kg: 80+/-4%). MHC disparate BM resulted in autologous reconstitution after conditioning by 10 mg/kg of the mAb and caused transient chimerism ending up in death associated with aplasia after conditioning by 15 mg/kg of the mAb. MHC haploidentical BM (F1 to parental) engrafted only after conditioning by 15 mg/kg (chimerism at day 100: 78+/-7%). Abandonment of α/β TCR+ cell depletion from BM grafts impaired the engraftment process after conditioning using 15 mg/kg of the mAb in the MHC syngeneic setting (2 of 6 recipients failed to engraft) and the MHC haploidentical setting (3 of 6 recipients failed). Conclusion This depletive anti-RT7a mAb is myelosuppressive and conditions for engraftment of MHC syngeneic BM. The mAb also facilitates engraftment of MHC haploidentical BM, if a myeloablative dose is used. RT7b expressing, BM-seeded α/β TCR+ cells seem to impair the engraftment process after myeloablative mAb conditioning. PMID

  8. Anti-CD45 radioimmunotherapy using 211At with bone marrow transplantation prolongs survival in a disseminated murine leukemia model

    Energy Technology Data Exchange (ETDEWEB)

    Orozco, Johnnie J.; Back, Tom; Kenoyer, Aimee L.; Balkin, Ethan R.; Hamlin, Donald K.; Wilbur, D. Scott; Fisher, Darrell R.; Frayo, Shani; Hylarides, Mark; Green, Damian J.; Gopal, Ajay K.; Press, Oliver W.; Pagel, John M.

    2013-05-15

    Anti-CD45 Radioimmunotherapy using an Alpha-Emitting Radionuclide 211At Combined with Bone Marrow Transplantation Prolongs Survival in a Disseminated Murine Leukemia Model ABSTRACT Despite aggressive chemotherapy combined with hematopoietic cell transplant (HCT), many patients with acute myeloid leukemia (AML) relapse. Radioimmunotherapy (RIT) using antibodies (Ab) labeled primarily with beta-emitting radionuclides has been explored to reduce relapse.

  9. Anti-CD45 Radioimmunotherapy with 90Y but Not 177Lu Is Effective Treatment in a Syngeneic Murine Leukemia Model

    OpenAIRE

    Orozco, Johnnie J.; Ethan R. Balkin; Gooley, Ted A.; Kenoyer, Aimee; Hamlin, Donald K.; Wilbur, D. Scott; Fisher, Darrell R.; Hylarides, Mark D.; Shadman, Mazyar; Green, Damian J.; Gopal, Ajay K.; Press, Oliver W.; Pagel, John M.

    2014-01-01

    Radioimmunotherapy (RIT) for treatment of hematologic malignancies has primarily employed monoclonal antibodies (Ab) labeled with 131I or 90Y which have limitations, and alternative radionuclides are needed to facilitate wider adoption of RIT. We therefore compared the relative therapeutic efficacy and toxicity of anti-CD45 RIT employing 90Y and 177Lu in a syngeneic, disseminated murine myeloid leukemia (B6SJLF1/J) model. Biodistribution studies showed that both 90Y- and 177Lu-anti-murine CD4...

  10. Anti-CD45 Pretargeted Radioimmunotherapy using Bismuth-213: High Rates of Complete Remission and Long-Term Survival in a Mouse Myeloid Leukemia Xenograft Model

    Energy Technology Data Exchange (ETDEWEB)

    Pagel, John M; Kenoyer, Aimee L; Back, Tom; Hamlin, Donald K; Wilbur, D Scott; Fisher, Darrell R; Park, Steven I; Frayo, Shani; Axtman, Amanda; Orgun, Nural; Orozoco, Johnnie; Shenoi, Jaideep; Lin, Yukang; Gopal, Ajay K; Green, Damian J; Appelbaum, Frederick R; Press, Oliver W

    2011-07-21

    Pretargeted radioimmunotherapy (PRIT) using an anti-CD45 antibody (Ab)-streptavidin (SA) conjugate and DOTA-biotin labeled with β-emitting radionuclides has been explored as a strategy to decrease relapse and toxicity. α-emitting radionuclides exhibit high cytotoxicity coupled with a short path-length, potentially increasing the therapeutic index and making them an attractive alternative to β-emitting radionuclides for patients with Acute Myeloid Leukemia (AML). Accordingly, we have used 213Bi in mice with human leukemia xenografts. Results demonstrated excellent localization of 213Bi-DOTA-biotin to tumors with minimal uptake into normal organs. After 10 minutes, 4.5 ± 1.1% of the injected dose of 213Bi was delivered per gram of tumor. α imaging demonstrated uniform radionuclide distribution within tumor tissue 45 minutes after 213Bi-DOTA-biotin injection. Radiation absorbed doses were similar to those observed using a β-emitting radionuclide (90Y) in the same model. We conducted therapy experiments in a xenograft model using a single-dose of 213Bi-DOTA-biotin given 24 hours after anti-CD45 Ab-SA conjugate. Among mice treated with anti-CD45 Ab-SA conjugate followed by 800 μCi of 213Bi- or 90Y-DOTA-biotin, 80% and 20%, respectively, survived leukemia-free for >100 days with minimal toxicity. These data suggest that anti-CD45 PRIT using an α-emitting radionuclide may be highly effective and minimally toxic for treatment of AML.

  11. Anti-CD45 radioimmunotherapy with 90Y but not 177Lu is effective treatment in a syngeneic murine leukemia model.

    Directory of Open Access Journals (Sweden)

    Johnnie J Orozco

    Full Text Available Radioimmunotherapy (RIT for treatment of hematologic malignancies has primarily employed monoclonal antibodies (Ab labeled with 131I or 90Y which have limitations, and alternative radionuclides are needed to facilitate wider adoption of RIT. We therefore compared the relative therapeutic efficacy and toxicity of anti-CD45 RIT employing 90Y and 177Lu in a syngeneic, disseminated murine myeloid leukemia (B6SJLF1/J model. Biodistribution studies showed that both 90Y- and 177Lu-anti-murine CD45 Ab conjugates (DOTA-30F11 targeted hematologic tissues, as at 24 hours 48.8 ± 21.2 and 156 ± 14.6% injected dose per gram of tissue (% ID/g of 90Y-DOTA-30F11 and 54.2 ± 9.5 and 199 ± 11.7% ID/g of 177Lu-DOTA-30F11 accumulated in bone marrow (BM and spleen, respectively. However, 90Y-DOTA-30F11 RIT demonstrated a dose-dependent survival benefit: 60% of mice treated with 300 µCi 90Y-DOTA-30F11 lived over 180 days after therapy, and mice treated with 100 µCi 90Y-DOTA-30F11 had a median survival 66 days. 90Y-anti-CD45 RIT was associated with transient, mild myelotoxicity without hepatic or renal toxicity. Conversely, 177Lu- anti-CD45 RIT yielded no long-term survivors. Thus, 90Y was more effective than 177Lu for anti-CD45 RIT of AML in this murine leukemia model.

  12. PLGA-PEG Nanoparticles Coated with Anti-CD45RO and Loaded with HDAC Plus Protease Inhibitors Activate Latent HIV and Inhibit Viral Spread

    Science.gov (United States)

    Tang, Xiaolong; Liang, Yong; Liu, Xinkuang; Zhou, Shuping; Liu, Liang; Zhang, Fujina; Xie, Chunmei; Cai, Shuyu; Wei, Jia; Zhu, Yongqiang; Hou, Wei

    2015-10-01

    Activating HIV-1 proviruses in latent reservoirs combined with inhibiting viral spread might be an effective anti-HIV therapeutic strategy. Active specific delivery of therapeutic drugs into cells harboring latent HIV, without the use of viral vectors, is a critical challenge to this objective. In this study, nanoparticles of poly(lactic-co-glycolic acid)-polyethylene glycol diblock copolymers conjugated with anti-CD45RO antibody and loaded with the histone deacetylase inhibitor suberoylanilide hydroxamic acid (SAHA) and/or protease inhibitor nelfinavir (Nel) were tested for activity against latent virus in vitro. Nanoparticles loaded with SAHA, Nel, and SAHA + Nel were characterized in terms of size, surface morphology, zeta potential, entrapment efficiency, drug release, and toxicity to ACH-2 cells. We show that SAHA- and SAHA + Nel-loaded nanoparticles can target latently infected CD4+ T-cells and stimulate virus production. Moreover, nanoparticles loaded with SAHA + NEL were capable of both activating latent virus and inhibiting viral spread. Taken together, these data demonstrate the potential of this novel reagent for targeting and eliminating latent HIV reservoirs.

  13. The antibody approach of labeling blood cells

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, S.C.

    1991-12-31

    Although the science of blood cell labeling using monoclonal antibodies directed against specific cellular antigens is still in its early stages, considerable progress has recently been accomplished in this area. The monoclonal antibody approach offers the promise of greater selectivity and enhanced convenience since specific cell types can be labeled in vivo, thus eliminating the need for complex and damaging cell separation procedures. This article focuses on these developments with primary emphasis on antibody labeling of platelets and leukocytes. The advantages and the shortcomings of the recently reported techniques are criticality assessed and evaluated.

  14. The antibody approach of labeling blood cells

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, S.C.

    1992-12-31

    Although the science of blood cell labeling using monoclonal antibodies directed against specific cellular antigens is still in its early stages, considerable progress has recently been accomplished in this area. The monoclonal antibody approach offers the promise of greater selectivity and enhanced convenience since specific cell types can be labeled in vivo, thus eliminating the need for complex and damaging cell separation procedures. This article focuses on these developments with primary emphasis on antibody labeling of platelets and leukocytes. The advantages and the shortcomings of the recently reported techniques are critically assessed and evaluated.

  15. The antibody approach of labeling blood cells

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, S.C.

    1991-01-01

    Although the science of blood cell labeling using monoclonal antibodies directed against specific cellular antigens is still in its early stages, considerable progress has recently been accomplished in this area. The monoclonal antibody approach offers the promise of greater selectivity and enhanced convenience since specific cell types can be labeled in vivo, thus eliminating the need for complex and damaging cell separation procedures. This article focuses on these developments with primary emphasis on antibody labeling of platelets and leukocytes. The advantages and the shortcomings of the recently reported techniques are criticality assessed and evaluated.

  16. The antibody approach of labeling blood cells

    International Nuclear Information System (INIS)

    Although the science of blood cell labeling using monoclonal antibodies directed against specific cellular antigens is still in its early stages, considerable progress has recently been accomplished in this area. The monoclonal antibody approach offers the promise of greater selectivity and enhanced convenience since specific cell types can be labeled in vivo, thus eliminating the need for complex and damaging cell separation procedures. This article focuses on these developments with primary emphasis on antibody labeling of platelets and leukocytes. The advantages and the shortcomings of the recently reported techniques are critically assessed and evaluated

  17. The antibody approach of labeling blood cells

    International Nuclear Information System (INIS)

    Although the science of blood cell labeling using monoclonal antibodies directed against specific cellular antigens is still in its early stages, considerable progress has recently been accomplished in this area. The monoclonal antibody approach offers the promise of greater selectivity and enhanced convenience since specific cell types can be labeled in vivo, thus eliminating the need for complex and damaging cell separation procedures. This article focuses on these developments with primary emphasis on antibody labeling of platelets and leukocytes. The advantages and the shortcomings of the recently reported techniques are criticality assessed and evaluated

  18. Stability of rhenium-188 labeled antibody

    International Nuclear Information System (INIS)

    For clinical application of beta-emitter labeled antibody, high specific activity is important. Carrier-free Re-188 from W-188/Re-188 generator is an ideal radionuclide for this purpose. However, low stability of Re-188 labeled antibody, especially in high specific activity, due to radiolytic decomposition by high energy (2.1 MeV) beta ray was problem. We studied the stability of Re-188 labeled antibody, and stabilizing effect of several nontoxic radical-quenching agents. Pre-reduced monoclonal antibody (CEA79.4) was labeled with Re-188 by incubating with generator-eluted Re-188-perrhenate in the presence of stannous tartrate for 2 hr at room temperature. Radiochemical purity of each preparation was determined by chromatography (ITLC-SG/acetone, ITLC-SG/Umezawa, Whatman No.1/saline). Human serum albumin was added to the labeled antibodies(2%). Stability of Re-188-CEA79.4 was investigated in the presence of vitamin C, ethanol, or Tween 80 as radical-quenching agents. Specific activities of 4.29∼5.11 MBq/μg were obtained. Labeling efficiencies were 88±4%(n=12). Very low stability after removal of stannous tartrate from the preparation was observed. If stored after purging with N2, all the preparations were stable for 10 hr. However, if contacted with air, stability decreased. Perrhenate and Re-188-tartrate was major impurity in declined preparation (12∼47 and 9∼38% each, after 10 hr). Colloid-formation was not a significant problem in all cases. Addition of vitamin C stabilized the labeled antibodies either under N2 or under air by reducing the formation of perrhenate. High specific activity Re-188 labeled antibody is unstable, especially, in the presence of oxygen. Addition of vitamin C increased the stability

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

    International Nuclear Information System (INIS)

    Many investigators have demonstrated the ability to treat hematologic malignancies with radiolabeled monoclonal antibodies targeting hematopoietic antigens such as anti-CD20 and anti-CD45. [1-5] Although the remission rates achieved with radioimmunotherapy (RIT) are relatively high, many patients subsequently relapse presumably due to suboptimal delivery of enough radiation to eradicate the malignancy. The dose-response of leukemia and lymphoma to radiation has been proven. Substantial amounts of radiation can be delivered by RIT if followed by hematopoietic cell transplantation to rescue the bone marrow from myeloablation.[ref] However, the maximum dose of RIT that can be used is still limited by toxicity to normal tissues affected by nonspecific delivery of radiation. Efforts to improve RIT focus on improving the therapeutic ratios of radiation in target versus non-target tissues by removing the fraction of radioisotope that fails to bind to target tissues and circulates freely in the bloodstream perfusing non-target tissues. Our group and others have explored several alternatives for removal of unbound circulating antibody. [refs] One such method, extracorporeal adsorption therapy (ECAT) consists of removing unbound antibody by a method similar to plasmapheresis after critical circulation time and distribution of antibody into target tissues have been achieved. Preclinical studies of ECAT in murine xenograft models demonstrated significant improvement in therapeutic ratios of radioactivity. Chen and colleagues demonstrated that a 2-hour ECAT procedure could remove 40 to 70% of the radioactivity from liver, lung and spleen. [ref] Although isotope concentration in the tumor was initially unaffected, a 50% decrease was noted approximately 36 hours after the procedure. This approach was also evaluated in a limited phase I pilot study of patients with refractory B-cell lymphoma. [ref] After radiographic confirmation of tumor localization of a test dose of anti-CD20

  20. Immobilization of antibodies and enzyme-labeled antibodies by radiation polymerization

    International Nuclear Information System (INIS)

    Immobilization of antibodies and enzyme-labeled antibodies by radiation polymerization at low temperatures was studied. The antibody activity of antibody was not affected by irradiation at an irradiation dose of below 8 MR and low temperatures. Immobilization of peroxidase-labeled anti-rabbit IgG goat IgG, anti-peroxidase, peroxidase, and anti-alpha-fetoprotein was carried out with hydrophilic and hydrophobic monomers. The activity of the immobilized enzyme-labeled antibody membranes varied with the thickness of the membranes and increased with decreasing membrane thickness. The activity of the immobilized antibody particles was varied by particle size. Immobilized anti-alpha-fetoprotein particles and membranes can be used for the assay of alpha-fetoprotein by the antigen-antibody reaction, such as a solid-phase sandwich method with high sensitivity

  1. Palladium-109 labeled anti-melanoma monoclonal antibodies

    Science.gov (United States)

    Srivastava, S.C.; Fawwaz, R.A.; Ferrone, S.

    1984-04-30

    The invention consists of new monoclonal antibodies labelled with Palladium 109, a beta-emitting radionuclide, the method of preparing this material, and its use in the radiotherapy of melanoma. The antibodies are chelate-conjugated and demonstrate a high uptake in melanomas. (ACR)

  2. Advances in 99mTc-labeling of antibodies

    International Nuclear Information System (INIS)

    Several methods have been developed to label antibodies with 99mTc. Direct labeling results in 99mTc binding to multiple sites of various affinities that are often weaker than the binding to strong chelating agents. Attempts to overcome this disadvantage involve conjugation of strong chelating agents to the antibodies. While stability is usually enhanced, this approach suffers from alteration of antibody properties as well as non-specific binding of 99mTc to the antibody instead of to the conjugation chelating agent. This has been of concern for studies with DTPA as the chelating agent. In this study the loss of 99mTc by N2S2 challenge shows that a fraction to the 99mTc is nonspecifically bound to the antibody. An advantage of the approach of labeling antibodies containing a bifunctional chelating agent is the simplicity of the labeling procedure and the apparent high yields that in reality are the sum of chelating agent and non-specifically bound radioactivity. The last approach described in our work of conjugation of a preformed chelate has advantages of characterizable 99mTc complex chemistry and conjugation by standard protein derivatization chemistry. Slow chelation kinetics can be overcome in the small molecule stage and then conjugation performed under mild conditions with respect to the antibody of fragments. This approach, however, suffers from greater complexity of the labeling process including multiple steps, purifications and non-quantitative yields. The use of ligands for 99mTc in which the complexes are of high stability and predictable chemistry is likely to result in eventual optimal labeling technologies. Processes which are non-specific may work in some cases, but are likely to present difficulties in optimization and general applicability from antibody to antibody. (orig.)

  3. Detection of thrombocyte antibodies by 125I labeled protein A

    International Nuclear Information System (INIS)

    Protein A from Staphylococcus aureus interacts in a specific manner with most subclasses of human IgG. In the present study a method is described which utilizes Protein A labeled with 125I for the detection of antibody sensitization of platelets. The clinical applicability of the test for detection of in vivo or in vitro sensitization is demonstrated in three patients with platelet antibodies. (author)

  4. Fluorescent labeling of antibody fragments using split GFP.

    Directory of Open Access Journals (Sweden)

    Fortunato Ferrara

    Full Text Available Antibody fragments are easily isolated from in vitro selection systems, such as phage and yeast display. Lacking the Fc portion of the antibody, they are usually labeled using small peptide tags recognized by antibodies. In this paper we present an efficient method to fluorescently label single chain Fvs (scFvs using the split green fluorescent protein (GFP system. A 13 amino acid tag, derived from the last beta strand of GFP (termed GFP11, is fused to the C terminus of the scFv. This tag has been engineered to be non-perturbing, and we were able to show that it exerted no effect on scFv expression or functionality when compared to a scFv without the GFP11 tag. Effective functional fluorescent labeling is demonstrated in a number of different assays, including fluorescence linked immunosorbant assays, flow cytometry and yeast display. Furthermore, we were able to show that this split GFP system can be used to determine the concentration of scFv in crude samples, as well an estimate of antibody affinity, without the need for antibody purification. We anticipate this system will be of widespread interest in antibody engineering and in vitro display systems.

  5. Potential application of labeled antibodies for thrombus detection

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-06-01

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

  8. Clinical application of antibody monoclonal humanized anti-EGFrnimotuzumab labeled

    International Nuclear Information System (INIS)

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

  9. The generation of rhenium-188-labeled antibodies by direct labeling methods

    International Nuclear Information System (INIS)

    Rhenium-188 having similar chemistry to Tc-99m and favorable decay properties, is an attractive agent for radioimmunotherapy, despite the greater difficulties in antibody labeling with this element. The authors have succeeded in generating a reproducible process for the production of 188Re-IgC conjugates in near quantitative yield with highly preserved immunoreactivity. Incubation of perrhenate with a thiol-containing antibody in the presence of a reductant gives rise to radiolabeled antibody in yields approaching > 95% at 1-3 hr time periods, with unreduced perrhenate as the only other species. 188Re from a 188W/188Re generator system has been used to label antibody with a specific activity up to 15 mCi/mg. Animal biodistribution in LS174T tumor bearing nude mice out to 96 hours verified its stability with good tumor/non-tumor ratios being seen, while the strong uptake and retention in the tumor further reinforced this conclusion. Use of this approach, with the readily available 188Re source from the generator, gives a clinically viable procedure for the generation of 188Re antibody conjugates ready for immediate therapeutic use in as simple a manner as the corresponding technetium conjugates are now used for radioimmunodetection

  10. Clearance of injected radioactively labelled antibodies to tumour products by liposome-bound second antibodies

    International Nuclear Information System (INIS)

    Liposomes containing anti-goat immunoglobulin were injected 24 h after administration of 125I-labelled goat antibody against the carcinoembryonic antigen (anti-CEA) to groups of nude mice bearing human tumour xenografts, and normal mice. Controls in each group received radioactively labelled anti-CEA only. In liposome-treated mice, blood 125I levels were lower than those of controls 30 min to 24 h after liposome administration, with corresponding accumulation of 125I activity in the liver and spleen for the first 2 h after liposome injection. [14C]Cholesterol or sup(99m)Tc labels in the bilayer were eliminated rapidly from the blood, with uptake in the liver and spleen. In xenograft-bearing mice, 125I activity detected in the tumours up to 6 h after liposome injection was identical to that detected in the tumours of controls. However, 24 h after liposome injection a reduction in the tumour concentration of 125I-labelled anti-CEA was obtained, but the tumour/blood radioactivity was still increased. In two mice given 27 μmol lipid, the blood radioactivity count after 24 h was only 5% of that in the controls. In rabbits, 2 h after administration of liposomes containing anti-goat second antibody, the circulating 125I activity had dropped by 28-40%. The results suggest that administration of liposome-entrapped second antibody approximately 2 h prior to external scintigraphy may clear circulating radioactively labelled primary antibody by up to 50%. (Auth.)

  11. Detection of HBs antigen in routine paraffin embedded liver tissue by enzyme-labelled antibody technique

    Directory of Open Access Journals (Sweden)

    Tsuji,Takao

    1976-02-01

    Full Text Available HB surface antigen (HBs Ag was detected using the enzyme-labelled antibody technique on routinely processed liver biopsy material fixed in Bouin's fixative and embedded in paraffin. Of 85 examined specimens, 45 cases were HBs Ag positive by both the immunofluorescent test and the enzyme labelled antibody technique. The remaining 40 cases were negative by both techniques. The specificity of HBs Ag detected by the enzyme-labelled antibody technique was confirmed by the blocking test using guinea pig specific HBs antibody. The results indicate that the enzyme-labelled antibody technique may be useful for detecting HBs Ag on routine paraffin sections.

  12. Radioimmunotherapy of infection with 213Bi-labeled antibodies

    OpenAIRE

    Dadachova, Ekaterina

    2008-01-01

    Bismuth-213 (213Bi) (physical half-life 46 min) is a beta-emitter (97%) and an alpha-emitter (3%) which decays to short lived alpha-emitter Polonium-213 and could therefore be used as an in vivo generator of alpha particles with the energy of around 8 MeV. 213Bi has been successfully used during the last decade in both clinical and pre-clinical work for radioimmunotherapy (RIT) of cancer with 213Bi-labeled monoclonal antibodies (mAbs). RIT has been proposed as a novel techonology for treatmen...

  13. 188Re-labelled anti-CD20 monoclonal antibody: Labelling and quality control studies

    International Nuclear Information System (INIS)

    Immunotherapy with human chimeric antibody rituximab (Rituxan, IDEC pharmaceuticals) has been a major advance in treatments of patients with CD20-positive B-cell non Hodgkin's lymphoma (NHL). Radioimmunotherapy (RIT) uses the targeting features of monoclonal antibody to deliver radiation from an attached readionuclide and it is an appeling concept that has received widespread attention. Here, we report our experience using rhenium-188 (188Re)- radiolabeled chimeric anti-CD20 antibody (rituximab). A stable antibody-labeling technique had been developed for 188Re. The 188Re-direct labeling of anti-CD20 monoclonal antibody, the methods for quality control: paper chromatography, instant thin layer chromatographysilica gel (ITLC-SG) and HPLC technique, the immunoreactivity and biological recognition of the target antigen assessment of the radiolabeled molecule, in vitro stability and the assessment of in vivo stability through biodistribution studies in normal WISTAR rats are described. For the direct radiolabeling, the reduction of monoclonal antibody (mAb) was performed with 2-mercaptoethanol (2-ME), based on Schwarz's method at a molar ratio 2000:1 (2- ME:mAb). By means of this method some of the disulfide bonds of the antibody are reduced to sulfhydryl groups (we obtained 4-5 groups) and these groups provide sites for the formation of very strong bond between the reduced rhenium and the antibody. The methodology used in this work has been tested in a phase I radioimmunotherapy clinical trial using the humanized mAb hR3 for loco-regional treatment of brain tumours. The labeling efficiency (> 95 %) of this method showed that the final product needs no further purification for clinical purposes (low level formation of colloidal species). In vitro stability studies of the labeled anti-CD20 were performed at room temperature at 4 h, 24 h and 48 h in cysteine, human serum and saline. In the presence of normal human serum, during the first 4h, transchelation of about 15

  14. Radioimmunoassay for antigliadin-antibodies using 14C-labelled gliadin

    International Nuclear Information System (INIS)

    A sensitive radioimmunoassay for antibodies to gliadin has been developed. Gliadin from wheat gluten was labelled with [1-14C]acetic anhydride to a specific activity of 2.6 x 106 dpm/mg. Immunological evidence is presented that the antigen was not essentially altered by the labelling procedure. Experimentally-induced antigliadin antibodies or sera of patients with coeliac disease (CD) were reacted with labelled gliadin and the immune complexes formed precipitated by antiglobulin. Precipitating antibodies were determined by incubating CD sera with labelled gliadin and measuring the radioacticity in precipitates formed without the addition of second antibody. Comparison with other methods for the detection of antigliadin antibodies, including immunoelectrophoresis, immunodiffusion and passive hemagglutination indicated that total and precipitating antibodies were determined only by RIA. The assay also provides information on the immunoglobulin class of antigliadin-antibodies present in sera of patients with coeliac disease

  15. Yttrium Y 90 Anti-CD45 Monoclonal Antibody BC8 Followed by Donor Stem Cell Transplant in Treating Patients With High-Risk Acute Myeloid Leukemia, Acute Lymphoblastic Leukemia, or Myelodysplastic Syndrome

    Science.gov (United States)

    2016-02-12

    Acute Myeloid Leukemia Arising From Previous Myelodysplastic Syndrome; Chronic Myelomonocytic Leukemia; Previously Treated Myelodysplastic Syndrome; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Acute Myeloid Leukemia; Refractory Anemia With Excess Blasts; Secondary Acute Myeloid Leukemia

  16. Production of radiolabeled monoclonal antibody conjugates by photoaffinity labeling

    Energy Technology Data Exchange (ETDEWEB)

    Volkert, W.A.; Ketring, A.R.; Kuntz, R.R.; Holmes, R.A.; Mitchell, E.P. (Missouri Univ., Columbia, MO (USA)); Feldbush, T.L. (Harry S. Truman Memorial Veterans Hospital, Columbia, MO (USA))

    1990-06-01

    This report discusses activities and progress that has occurred since initiation of this project on September 1, 1989. We have synthesized ethyl N,N{prime}-bis(benzoylmercaptoacetyl)-2,3-diaminopropanoate, a ligand to be used as a bifunctional chelating agent (BFCA), to form {sup 186}Re or {sup 188}Re ({sup 186}Re/{sup 188}Re) complexes. {sup 186}Re/{sup 188}Re, in reducing media, reacts with this ligand to form {sup 186}Re/{sup 188}Re-CO{sub 2}DADS chelates that will be used to formulate new radiolabeled photoaffinity labels (RPALs). Initial steps have been taken to synthesize R-As-dithiol compounds. This approach will be used to produce {sup 77}As-RPALs or covalently link {sup 77}As directly to monoclonal antibodies (MAbs). The R group will contain a group that can be used for conjugation reactions. Spectral and photochemical properties of various types of photoaffinity labels (PALs) have been studied. Acrylo-azido compounds and 9-azido acridine have been studied as well as several other photoprobes. The binding characteristics of the azido-based PALs to HSA have been studied and progress has been made on developing techniques for efficiently separating of non-covalently sound PALs. The Nd-YAG laser was purchased and arrived in 1990. It has been assembled and tested and is now operational.

  17. Pharmacokinetics of internally labeled monoclonal antibodies as a gold standard: comparison of biodistribution of 75Se-, 111In-, and 125I-labeled monoclonal antibodies in osteogenic sarcoma xenografts in nude mice

    International Nuclear Information System (INIS)

    In order to know the true biodistribution of anti-tumor monoclonal antibodies, three monoclonal antibodies (OST6, OST7, and OST15) against human osteosarcoma and control antibody were internally labeled with 75Se by incubating [75Se]methionine and hybridoma cells. 75Se-labeled monoclonal antibodies were evaluated both in vitro and in vivo using the human osteogenic sarcoma cell line KT005, and the results were compared with those of 125I- and 111In-labeled antibodies. 75Se-, 125I- and 111In-labeled monoclonal antibodies had identical binding activities to KT005 cells, and the immunoreactivity was in the decreasing order of OST6, OST7, and OST15. On the contrary, in vivo tumor uptake (% injected dose/g) of 75Se- and 125I-labeled antibodies assessed using nude mice bearing human osteosarcoma KT005 was in the order of OST7, OST6, and OST15. In the case of 111In, the order was OST6, OST7, and OST15. High liver uptake was similarly seen with 75Se- and 111In-labeled antibodies, whereas 125I-labeled antibodies showed the lowest tumor and liver uptake. These data indicate that tumor targeting of antibody conjugates are not always predictable from cell binding studies due to the difference of blood clearance of labeled antibodies. Furthermore, biodistribution of both 111In- and 125I-labeled antibodies are not identical with internally labeled antibody. Admitting that internally labeled antibody is a ''gold standard'' of biodistribution of monoclonal antibody, high liver uptake of 111In-radiolabeled antibodies may be inherent to antibodies. Little, if any, increase in tumor-to-normal tissue ratios of antibody conjugates will be expected compared to those of 111In-labeled antibodies if stably coupled conjugates are administered i.v

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

    International Nuclear Information System (INIS)

    With an aim to develop a method to produce labelled antibodies with low immunogenicity, two recombinant fusion proteins; scFv-His and scFv-MTβ were produced using gene engineering techniques. The former was constructed with scFv-antibody and histidine hexamer, a metal-chelated protein (or peptide). The latter was done with scFv-antibody and β-domain of metallothionein. Then, antigen-binding activity and metal-binding activity of these fusion proteins were determined using gel-filtration chromatography and ELISA. The main antigen-binding activity of scFv-His preparation was detected in a domain of about 25-30 kDa, which agreed with the peak of 29 kDa corresponding to the presumed molecular weight for the protein. Whereas the antigen-binding activity of scFv-MTβ was found in a domain of 30-35 kDa, which agreed with 32 kDa, the presumed molecular weight of scFv-MTβ. Gel-filtration chromatography of scFv-His preparation after the addition of Cu2+ ion revealed an optical absorption at 280 nm and a Cu-peak near at 14 kDa. These results suggested that the metal affinity of the histidine-hexamer was too weak to chelate Cu2+ in a solution. The chromatography of scFv-MTβ preparation added with Cd2+ showed a peak of Cd appeared around a position of about 20 kDa but the peak was not coincident with that of the antigen-binding activity (ca. 30 kDa), suggesting that the present preparation of scFv-MTβ had no Cd-binding activity due to metal-exchange reaction. Based on these results, problems on the production of recombinant scFv-antibody fused with metal-binding domain of cystein-binding type or histidine-binding one were discussed. (M.N.)

  19. Radioimmunoassay for anticollagen-antibodies using 14C-labelled collagen

    International Nuclear Information System (INIS)

    A sensitive radioimmunoassay for anticollagen antibodies is described. 14C-labelled human acid-soluble collagen of high specific activity (5 x 106 dpm/mg) is used as antigen either in native or denatured state. Experimentally induced anticollagen antibodies or RA synovial fluids containing antibodies to collagen are reacted with the labelled antigen. The immune complexes formed are precipitated with goat antiserum to rabbit globulins ('second antibody'). A systematic investigation of the labelled collagen in regard to cleavage by enzymes, fibril formation and specificity showed that no gross alteration had been caused by the labelling procedure. The assay furnishes information on the avidity, specificity and immunoglobulin class of experimental or pathological anticollagen antibodies. It can also be used as sensitive assay for collagen in biological fluids

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

    International Nuclear Information System (INIS)

    Reduction of disulfide bonds to sulfhydryl groups for direct radiolabelling of monoclonal antibodies for immunoscintigraphic application continues to be of significant interest. Reducing agents that have been used are the following: stannous ion, 2-mercaptoethanol, dithiothreitol, dithioerythriol, and ascorbic acid. The radiolabelling of the reduced and purified antibody is performed via Sn2+ reduction of pertechnetate in the presence of an excess of a low-affinity chelating ligand. In a recent work the 2-mercaptoethanol (2-ME) reduction based method was studied by using different analytical and biological techniques. Human IgG (Sandoglobulin), anti-CEA MoAb (ior-1), and anti-granulocyte MoAb (MAK 47), were reduced with 2-ME at two different molar ratios. To determine the amount of contaminating mercaptoethanol which may have survived the gel-filtration step 14C-ME was used. The number of the free endogenous sulfhydryl groups generated by reduction was determined by Ellman's reagent; absorbance was measured at 412 nm. Within the quality assurance procedure of the 3 freeze dried kits the labelling efficiency, stability, pH, sterility, apyrogenicity, vial yield, syringe retention, filterable activity, free SH determination and animal distribution were studied again. After receiving permission from local ethics committee pilot human studies were initiated. Study protocols were also approved

  1. Labeling and use of monoclonal antibodies in immunofluorescence: protocols for cytoskeletal and nuclear antigens.

    Science.gov (United States)

    Bauer, Christoph R

    2014-01-01

    Antibodies are widely used to target and label specifically extra- or intracellular antigens within cells and tissues. Most protocols follow an indirect approach implying the successive incubation with primary and secondary antibodies. In these protocols the primary antibodies are specifically targeted against the antigen in question and are normally not labeled. The secondary antibodies come from a different species and are in contrast fluorescently labeled. The idea is that the primary antibodies specifically bind to their targets but cannot be visualized directly. Only binding of the secondary (fluorescent) antibodies to the constant region of the primary antibodies allows consecutively the visualization in a fluorescent microscope.Primary antibodies can be either of monoclonal (normally produced in mouse) or of polyclonal origin (normally produced in rabbit, goat, sheep, or donkey). Using (primary) monoclonal antibodies has the clear advantage that all antibodies used are identical in origin and behavior and should thus give a more clear-cut labeling result. On the other hand the demands towards labeling protocols might be concomitantly higher: Binding of primary antibodies will only occur if fixation and labeling protocols preserve the antigen sufficiently to keep its specific and unique target structure available. One could imagine that for polyclonal antibodies this demand is slightly lower as there is a pool of antibodies with varying specificities against multiple parts of their target antigens. Certain fractions of this pool might thus tolerate a larger variety of conditions, and consequently a larger variety of protocols might still result in successful labeling.Each step in a labeling protocol can be decisive for the outcome of an experiment especially if monoclonal antibodies are used. Especially critical are choice of buffer and fixation and permeabilization parameters of the protocol.In this chapter we discuss and detail proven protocols using

  2. Radioimmunoimaging of human colon carcinoma xenografts in nude mice with 111In-labelled monoclonal antibody

    International Nuclear Information System (INIS)

    A nude mouse model bearing human colon carcinoma xenograft from human fresh surgical specimens was established. The anti-colon carcinoma monoclonal antibody 2C10 was labelled with 111In using bifunctional chelating agent DTPA. The labelled antibodies were injected intraperitoneally into the tumor-bearing mice. The tissue distribution of labelled antibody was studied and whole body scintigraphies were obtained with a γ camera at different times. 96 hours after administration, the tumor to muscle ratio was 10.48, tumor to blood ratio 3.94 and tumor to liver ratio 1.58. There were significant difference in T/N ratio between animals receiving the specific antibody and labelled unrelated mouse IgG. Imaging showed clear tumor pictures in all animals receiving the specific McAb, while the two animals receiving unrelated mouse IgG showed negative imaging

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

    International Nuclear Information System (INIS)

    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 111In-labeled anti-CEA antibody (C110) or 111In-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 111In-labeled biotin (EB1) 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)

  4. Radionuclide imaging of primary renal-cell carcinoma by I-131-labeled antitumor antibody

    International Nuclear Information System (INIS)

    A goat antibody against human renal-cell carcinoma reacted on immunofluorescence with renal-cell carcinomas from 20 patients, but not with normal adult human tissues, including kidney. After i.v. administration the I-131-linked antibody showed preferential tumor localization in six of seven patients with primary renal carcinoma. Labeled antitumor antibodies may have the specificity for tumor imaging that current radiopharmaceuticals lack

  5. Stability of 188Re Labeled antibody for radioimmunotherapy and the effect of stabilizing agents

    International Nuclear Information System (INIS)

    For clinical application of beta-emitter labeled antibody, high specific activity is important. Carrier-free 188Re from 188W/ 188Re generator is an ideal radionuclide for this purpose. However, low stability of 188Re labeled antibody, especially in high specific activity, due to radiolytic decomposition by high energy (2.1 MeV) beta ray was problem. We studied the stability of 188Re labeled antibody, and stabilizing effect of several stabilizers. Pre-reduced monoclonal antibody (CEA79.4) was labeled with 188Re by incubating with generator-eluted 188Re-perrhenate in the presence of stannous tartrate for 2 hr at room temperature. Radiochemical purity of each preparation was determined by chromatography. Human serum albumin was added to the labeled antibodies (2%). Stability of 188Re-CEA79.4 was investigated in the presence of ascorbic acid, ethanol, or Tween 80 as stabilizing agents. Labeling efficiencies were 88±4% (n=12). Specific activities of 1.25 ∼4.77 MBq/μg were obtained. If stored after purging with N2, all the preparations were stable for 10 hr. However, stability decreased in the presence of air. Perrhenate and 188Re-tartrate was major impurity in declined preparation. Colloid-formation was not a significant problem in all cases. Addition of ascorbic acid stabilized the labeled antibodies either under N2 or under air by reducing the formation of perrhenate. High specific activity 188Re labeled antibody is unstable, especially, in the presence of oxygen. Addition of ascorbic acid increased the stability

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

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, J.G.V.C.; Toledo, V.P.C.P.; Guimaraes, T.M.P.D.; Bernardo-Filho, M.; Simal, C.J.R.; Mota, L.G.; Diniz, S.O.F.; Cardoso, V.N. E-mail: cardosov@farmacia.ufmg.br

    2002-05-01

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

  9. Biodistribution Analyses of a Near-Infrared, Fluorescently Labeled, Bispecific Monoclonal Antibody Using Optical Imaging.

    Science.gov (United States)

    Peterson, Norman C; Wilson, George G; Huang, Qihui; Dimasi, Nazzareno; Sachsenmeier, Kris F

    2016-04-01

    In recent years, biodistribution analyses of pharmaceutical compounds in preclinical animal models have become an integral part of drug development. Here we report on the use of optical imaging biodistribution analyses in a mouse xenograft model to identify tissues that nonspecifically retained a bispecific antibody under development. Although our bispecific antibody bound both the epidermal growth factor receptor and insulin growth factor 1 receptor are expressed on H358, nonsmall-cell lung carcinoma cells, the fluorescence from labeled bispecific antibody was less intense than expected in xenografted tumors. Imaging analyses of live mice and major organs revealed that the majority of the Alexa Fluor 750 labeled bispecific antibody was sequestered in the liver within 2 h of injection. However, results varied depending on which near-infrared fluorophore was used, and fluorescence from the livers of mice injected with bispecific antibody labeled with Alexa Fluor 680 was less pronounced than those labeled with Alexa Fluor 750. The tissue distribution of control antibodies remained unaffected by label and suggests that the retention of fluorophores in the liver may differ. Given these precautions, these results support the incorporation of optical imaging biodistribution analyses in biotherapeutic development strategies. PMID:27053562

  10. Problems in the application of labelled antibody techniques to communicable and parasitic diseases

    International Nuclear Information System (INIS)

    Two-site immunoradiometric and universal reagent techniques, using radiolabelled antibody, may be applied to communicable diseases. Labelled antibody techniques avoid the problems of purifying and then atraumatically radioiodinating the microorganismal antigens for radioimmunoassay. The application of solid-phase radiolabelled techniques to detect antigenaemia and circulating antibodies in mycobacterial diseases and amoebiasis caused by Mycobacterium tuberculosis and Entamoeba histolytica is described. Methods of antibody radioiodination (Chloramine-T, lactoperoxidase and iodogen) are compared, as well as the relative efficacy of labelling immunoglobulin sodium sulphate precipitate fractions vis-a-vis antibodies purified by affinity chromatography on antigen linked to immunoadsorbents (CNBr Sepharose 4B, diazocellulose). The problems of non-specific reactions because of interglobulin reactions or sticky IgM antibodies adhering to plastic solid phases are emphasized. Serious problems may arise if the antisera employed for labelling have themselves been raised against immunogens with complete Freund' s adjuvant because of anti-mycobacterial antibodies. A non-specific reaction in a communicable disease/infestation may represent a low level of exposure and a low level specific reaction, and the problem of obtaining non-infected non-exposed controls arises. Even neonatal blood may contain material IgG antibodies. Various methods of minimizing non-specific interglobulin reactions are stressed to obtain optimal sensitivity, as well as the need for 'matching' the specific antiserum and the universal reagent. Reference is made to the use of monoclonal antibodies derived from in vitro hybridomas in overcoming some of the problems at present limiting the labelled antibody techniques

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

    International Nuclear Information System (INIS)

    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 111In-labeled anti-CEA antibody (C110) or 111In-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 111In-labeled biotin (EB1) 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)

  12. Labelling of monoclonal antibodies with 99Tcm, their quality control and evaluation for scintigraphy

    International Nuclear Information System (INIS)

    Several clinical studies have demonstrated that both the 111In and 99Tcm labelled specific monoclonal antibodies and non specific human immunoglobulins can delineate variety of cancerous infectious and inflammatory lesions. However, due to practical advantages of 99Tcm over 111In, 99Tcm labelled antibodies have exhibited distinct advantages for clinical investigations. Although the most stable and specific method for labelling antibodies with 99Tcm is performed by the bifunctional approach, there has recently been an increased interest in direct labelling methods as a result of significant improvement in the stability of the radiolabel and its potential application in the form of kits which can produce 99Tcm-antibody complex at the time of use. Direct methods based on the use of 2-mercaptoethanol ascorbic acid, borohydride and boric acid buffer appeared most promising. In addition, the method based on the use of iminothiolane to provide 99Tcm attachment site on the lysine has also been claimed a good practical method. We have evaluated these methods for radiolabelling of antibodies with 99Tcm using human immunoglobulin (hIgG) and an anti CEA mouse monoclonal antibody (ior-CEA-1) by studying labelling efficiency, in vitro serum stability, relative radionuclide binding strength, immunoreactivity, blood kinetics, biodistribution, specific target scintigraphy and also for development of lyophilized kits. The study has led to the improvement of the method based on the use o 2-ME and development of a novel method which uses ascorbic acid (ASC) to label the antibodies with 99Tcm and the production of lyophilized kits which give quality 99Tcm-hIgG and 99Tcm-ior-CEA-1 instantly when mixed with 99Tcm-pertechnetate. Both the products prepared from the kits have been found suitable for immunoscintigraphy

  13. Labelling of Rh antibodies on solid-phase protein A

    International Nuclear Information System (INIS)

    Rh0(D) antibodies which retain immune specificity after radiolabeling were prepared by a procedure which does not require IgG isolation from serum, requires 10-fold less isotope than conventional techniques and yields antibody solutions of defined composition. The method involves radioiodination of IgG on immobilized protein A, depends on employing human red cells reduced in surface cytophilic IgG, and exploits the inability of goat IgG to interact with Staphylococcus aureus protein A. The technique concentrates IgG by affinity adsorption and should prove useful in preparing radiolabeled alloantibodies from dilute human antisera and for red cell autoantibodies. (Auth.)

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

    International Nuclear Information System (INIS)

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

  15. A study of interaction between FITC- labeled antibody and optical fiber surface

    Science.gov (United States)

    Chao, K. F.; Zhang, Y. L.; Kong, X. G.; Zeng, Q. H.; Liu, R. L.; Wang, X.; Feng, L. Y.; Sun, Y. J.

    2006-01-01

    The immobilization of antibodies on solid surface has been widely studied in elucidating immunoassay and in developing immunosensor. In this paper, FITC-labeled goat anti-human IgG were covalently immobilized on 3-aminopropyltriethoxysilane (APTES) and glutaraldehyde (Glu) to modify the distal end of a fiber-optic probe. The higher density and stability of FITC-labeled goat anti-human IgG could be obtained on the fiber surface modified with APTES-Glu than that on the non-modified fiber surface by evanescent excited fluorescence spectroscopy. Furthermore, red shift of the FITC fluorescence dye emission peak was observed on different fiber surface, exhibiting different interaction between FITC- labeled antibody and surface. Finally, under these conditions antigen-antibody reaction was investigated as an immunosensor. Detection limit of the evanescent wave optic-fiber biosensor is 10ng/ml.

  16. Indium-111 labeled anti-melanoma monoclonal antibodies

    Science.gov (United States)

    Srivastava, S.C.; Fawwaz, R.A.; Ferrone, S.

    1984-04-30

    A monoclonal antibody to a high molecular weight melanoma-associated antigen was chelated and radiolabeled with indium-111. This material shows high affinity for melanoma and thus can be used in the detection, localization and imaging of melanoma. 1 figure.

  17. The use of radiolabeled monoclonal antibodies for cell labeling in vivo

    International Nuclear Information System (INIS)

    The authors have evaluated the potential of in vivo cell surface labeling using radiolabeled monoclonal antibodies (MoAbs) directed against their surface antigens. Two MoAbs, a specific antibody (anti-Thy-1 OX7) and a nonspecific control antibody (anti-CEA) were coupled with DTPA, labeled with /sup 111/In and evaluated against rat thymocytes, marrow cells, and lymphoma cells (all known to be Thy-1 positive) both in vitro and in vivo. Enumeration of the cells which bound the radiolabeled MoAb was done by detecting the antibody on the cell surface with a Fl-F(ab')/sub 2/ goat anti-mouse IgG and analyzing fluorescence (F1) in a flow cytometer (FACS). The thymocytes, which could be labeled in whole blood, showed a labeling efficiency of 80-100%. The labeling, which could be inhibited by cold antibody, was stable up to 72 hours and did not interfere with either cell viability or functional integrity. Following IV injection of the MoAbs in normal rats, there was very good visualization of the bone marrow not seen with the control. Analysis of the marrow cells on the FACS showed that at two hours over 60% of the marrow cells were specifically labeled as against 2% for the control. Within 15 minutes of injecting /sup 111/In-OX7 into rats with lymphoma, 70% of the activity in blood was bound to circulating lymphoma cells. The ability to stably label, rapidly target, and image specific cell populations in vivo has wide ranging diagnostic and therapeutic implications

  18. Radioimmunotherapy with 90Y-labeled monoclonal antibodies in a nude mouse ovarian cancer model

    International Nuclear Information System (INIS)

    Tumor stroma contains much fibrin, and so monoclonal antifibrin antibody can accumulate in tumors. We treated nude mice bearing human ovarian carcinoma xenografts with 90Y-labeled monoclonal antifibrin antibody Fab fragments administered intratumorally. The survival time vs. a control group was significantly prolonged and tumor growth rate was decreased. Another group of animals was treated with 90Y-labeled OC 125-monoclonal antibody; these mice received the antibodies intratumorally, intraperitoneally or intravenously. The survival time was longest in the intratumorally treated group. There was no significant difference in survival between 90Y-labeled OC 125 and antifibrin in the intratumorally treated animal groups. The tissue activity distribution studies revealed that bone marrow is the critical organ. Intratumorally injected monoclonal 90Y-antifibrin antibodies were retained at least 36 h (up to 50% of injected activity per gram tumor tissue) in the xenograft after one treatment, causing cell death. Beta-camera imaging and immunohistochemistry were performed for studies of the correlation between 90Y activity and fibrin distribution in tumor specimens. These results were in concordance. In conclusion, intratumoral administration seems suitable for radioimmunotherapy, with an antibody that targets stromal structures. The accumulation can be successfully monitored by a beta-camera. (orig.)

  19. Labelling immunoelectrophoresis: A general method for increasing the sensitivity of rocket immunoelectrophoresis with 125I-labelled anti-antibodies

    International Nuclear Information System (INIS)

    In a new procedure, rocket immunoelectrophoresis is performed at pH 8.7 with rabbit antibodies and 5% polyethyleneglycol 6000 in the agarose gel. After the pH in the gel has been changed to 5 the nonprecipitated immunoglobulins are electrophoresed out of the gel simultaneously with the electrophoresis of 125 I labelled swine antibodies against rabbit IgG into the gel. The latter antibodies tag the rabbit IgG, which is now present only in the precipitates. The radioactive precipitates are visualizes by autoradiography. The method permits quantification of antigens down to an amount of approximately 0.5 ng; well-defined rockets are not formed below this limit. Compared to conventional protein staining with Coomassie brilliant blue, this represents an increase in sensitivity of up to 20 times. (author)

  20. Considerations in the radioiodination and chelation labeling of an antiplatelet monoclonal antibody

    International Nuclear Information System (INIS)

    Radiolabeling of antibodies in particular with iodine nuclides frequently alters their biological behavior and compromises the specificity of binding to the in vivo antigens. Sensitivity to labeling chemistry however, is quite variable for different antibodies. This study was carried out to investigate the various factors affecting the binding to platelets (P) of an anti-P monoclonal antibody, 7E3, following iodination with I-123, I-125, I-131 and chelation labeling with In-111 and Tc-99m. Parameters such as the nature and amount of oxidant, reaction times, substitution level, specific activity etc., were studied. Results showed that each factor in addition to affecting chemical labeling yields also affected the binding of labeled 7E3 to P in whole blood and their blood clearance and clot uptake. With increasing I/7E3 or DTPA/7E3 molar ratios, a progressive decrease in binding to P resulted. Chloramine T (5-10 μg/100 μg 7E3) was superior to other oxidizing agents but the reaction times had to be ≤2 min (labeling yields 70 +- 10%). 7E3 appeared unaffected by specific activities of up to 40 μCi/μg (I-131 and In-111) and 300 μCi/μg (I-123). Satisfactory In-111-, I-131-, or I-123-7E3-P preparations were obtained that show considerable promise for localizing in vivo thrombi. Results of this study and prior experience with other antibodies indicate that in order to achieve maximum efficacy in imaging or therapy applications, individual antibodies may require a careful optimization of labeling procedures with different radionuclides

  1. A new monoclonal antibody radiopharmaceutical for radioimmunoscintigraphy of breast cancer: direct labeling of antibody and its quality control

    Directory of Open Access Journals (Sweden)

    Mojtaba Salouti

    2006-03-01

    Full Text Available Radioimmunoscintigraphy (RIS has found widespread clinical application in tumor diagnosis. The antibody (Ab PR81 is a new murine anti-MUC1 monoclonal antibody (MAb against human breast carcinoma. In this study a very simple, rapid and efficient method for labeling of this MAb with 99mTc, particularly suitable for development of a ‘kit’is described. The reduction of Ab was performed with 2-mercaptoethanol (2-ME at a molar ratio of 2000:1 (2-ME:MAb and the reduced Ab was labeled with 99mTc via methylene diphosphonate (MDP as a transchelator. The labeling efficiency which was determined by instant thin layer chromatography (ITLC was 94.2%±2.3. Radiocolloides measured by cellulose nitrate electrophoresis were 2.5%±1.7. In vitro stability of the labeled product in human serum which was measured by gel filtration chromatography (FPLC was 70%±5.7 over 24 hr. The integrity of labeled MAb was checked by means of SDS-PAGE and no significant fragmentation was observed. The results of the cell-binding studies showed that both labeled and unlabeled PR81 were able to compete for binding to MCF 7 cells. Biodistribution studies were performed in normal BALB/c mice at 4 and 24 hrs post-injection and no important accumulation was observed in vital organs. These results show that the new radiopharmaceutical may be considered as a promising candidate for imaging of breast cancer.

  2. Preparation of bromine-77 labelled monoclonal anti-hPLAP [human placental alkaline phosphatase] antibody using chloramine-T

    International Nuclear Information System (INIS)

    A tumor-associated monoclonal antibody, named 7E8 and raised against human placental alkaline phosphatase (hPLAP), is labelled with bromine-77 by means of chloramine-T. The paper describes optimum radiobromination conditions resulting in 34 % radiochemical yield of labelled antibody with more than 90 % immunoreactivity. (author)

  3. Technetium-99m labelling of the IOR CEA 1 monoclonal antibody: evaluation of different methods

    International Nuclear Information System (INIS)

    Aim: The aim of this study was to investigate the in vivo and in vitro properties of 99mTc labelled monoclonal antibody, IOR CEA 1 when radiolabelled by different methods. Methods: To achieve that purpose IOR CEA was directly radiolabelled via 2-mercaptoethanol (2-Me) and stannous ion (SnCl2) reduction and indirectly via the 2-iminothiolane (2-Im) conjugation. The resulting 99mTc-MoAbs were analysed for number of free sulfhydryl groups, chemical and radiochemical purity (checked by HPLC and SDS PAGE), immunoreactivity and biological distribution in mice. Results: Experimental results indicated a similar radiochemical purity and immunoreactivity for direct labelling methods and a decrease of both for 2-Im method. 2-Me antibody reduction led to a high antibody fragmentation as indicated by non-denaturing SDS PAGE analysis. Nevertheless SnCl2 and 2-Im labels revealed lower in vivo stability. Conclusion: 99mTc-(2-Me) IOR CEA presented favourable in vitro and in vivo properties. Therefore this label was compared to 99mTc-monoclonal antibody BW 431/26. Similar characteristics were found. Clinical studies also revealed identical biodistribution profile. (orig.)

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

    International Nuclear Information System (INIS)

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

  5. Rapid diagnosis of occult abscesses using sup 99m Tc-labeled monoclonal antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Coons, T.A.; Rhodes, B.A. (RhoMed, Inc., Albuquerque, NM (USA)); Thakur, M.L. (Thomas Jefferson Univ., Philadelphia, PA (USA)); Marcus, C.S. (Harbor-UCLA Medical Center, Torrance, CA (USA)); Ballou, B. (Pittsburgh Univ., PA (USA))

    1991-01-01

    Acute infections, such as appendicitis and occult infections in AIDS patients, can be diagnosed within two hours by gamma scintigraphy after i.v. administration of {sup 99m}Tc labeled antibodies reactive with human granulocytes. The antibody, murine IgM anti-SSEA-1, is partially reduced using Sn(II) to expose and protect reactive sulfide groups. The antibody is then purified, stannous tartrate and stabilizers are added, and the mixture is lyophilized. To label, sodium pertechnetate is added. After a 15 minute incubation the tracer drug is injected. The rate of accumulation and degree of concentration at the site of infection is presumptively determinative of the severity of the infection. Acceptance criteria and tests for the {sup 99m}Tc labeled antibody product have been established and validated. Greater than 93% of the {sup 99m}Tc is firmly bound to the protein as determined by quantitative HPLC. Radiochemical impurities, colloidal {sup 99m}Tc and free pertechnetate are together less than 4% as determined by thin layer chromatography. The immunoreactive fraction, measured by binding to solid phase antigen, and affinity measured be ELISA, are unchanged by the {sup 99m}Tc-direct labeling process. Two hour blood clearance in rats is within 90% of the value of the {sup 125}I labeled analog. The immunoreactive fraction decreases less than 10% when incubated in human plasma for 24 hours. This method has been compared to other direct labeling methods, and found to give higher radiochemical yields. 5 figs.

  6. 99m-technetium labelling of a tumor associated murine monoclonal antibody for immunoscintigraphic studies in man

    International Nuclear Information System (INIS)

    The present study refers to the preparation of a 99m-Technetium labelled murine monoclonal antibody for clinical application. The monoclonal antibody was incubated with a 20fold molar excess of 2-iminothiolane. The free thiol groups created, were capable of binding reduced technetium. Labelling took place through an exchange reaction with 99m-Technetium-Glucoheptonate. The labelling conditions were studied extensively. (Author)

  7. Flow cytometric measurement of RNA synthesis using bromouridine labelling and bromodeoxyuridine antibodies

    DEFF Research Database (Denmark)

    Jensen, P O; Larsen, J; Christiansen, J;

    1993-01-01

    Nuclear RNA synthesis can be analysed by flow cytometry of cells labelled with 5-bromouridine (BrUrd) and stained with anti-bromodeoxyuridine (BrdUrd) antibody and FITC-conjugated secondary antibody. A panel of 5 different commercially available anti-BrdUrd antibodies was tested on cells of a HL-60...... human leukemia cell line, stained as a methanol-fixed nuclear suspension. The BrUrd-induced fluorescence signals were highest with the antibody ABDM (Partec), moderate but reproducible with B-44 (Becton Dickinson), variable or low with BR-3 and IU-4 (Caltag), and not detectable with Bu20a (DAKO...... variation of RNA synthesis during the cell cycle. The BrUrd incorporation was high in the S and G2 phase, variable in G1, and negligible in mitosis. Similar results were obtained using other cell types....

  8. Indirect 125I-labeled protein A assay for monoclonal antibodies to cell surface antigens

    International Nuclear Information System (INIS)

    An assay for detection of monoclonal hybridoma antibodies against cell surface antigens is described. Samples of spent medium from the hybridoma cultures are incubated in microtest wells with cells, either as adherent monolayers or in suspension. Antibodies bound to surface antigens are detected by successive incubations with rabbit anti-immunoglobulin serum and 125I-labeled protein A from Staphylococcus aureus, followed by autoradiography of the microtest plate or scintillation counting of the individual wells. Particular advantages of this assay for screening hybridomas are: (1) commercially available reagents are used, (2) antibodies of any species and of any immunoglobulin class or subclass can be detected, and (3) large numbers of samples can be screened rapidly and inexpensively. The assay has been used to select hybridomas producing monoclonal antibodies to surface antigens of human melanomas and mouse sarcomas. (Auth.)

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

    International Nuclear Information System (INIS)

    Four dogs with histologically confirmed osteogenic sarcoma were studied with PET following intravenous injection of the 18F-labeled Fab fragment of TP-3, a monoclonal antibody specific for human and canine osteosarcomas. The antibody fragment was labeled using the N-succinimidyl (8-(4'-(18F)fluorobenzyl)amino)suberate acylation agent. Blood clearance of activity was biphasic in all dogs but half-times were variable (T1/2β = 2-13 hr). Catabolism of labeled Fab was reflected by the decrease in protein-associated activity in serum from more than 90% at 1 min to 60%-80% at 4 hr. PET images demonstrated increased accumulation of 18F at the primary tumor site relative to normal contralateral bone in one dog as early as 15 min after injection. Biopsies obtained after euthanasia indicated higher uptake at the edges of the tumor as observed on the PET scans. Tumor uptake was 1-3 x 10-3% injected dose/g, a level similar to that reported for other Fab fragments in human tumors. In the three dogs with metastatic disease, early PET images reflected activity in the blood pool but later uptake was observed in suspected metastatic sites. These results, although preliminary, suggest that PET imaging of 18F-labeled antibody fragments is feasible and that dogs with spontaneous tumors could be a valuable model for preclinical research with radioimmunoconjugates. 34 refs., 6 figs., 2 tabs

  10. Patient biodistribution of intraperitoneally administered yttrium-90-labeled antibody.

    Science.gov (United States)

    Hnatowich, D J; Chinol, M; Siebecker, D A; Gionet, M; Griffin, T; Doherty, P W; Hunter, R; Kase, K R

    1988-08-01

    Although 90Y is one of the best radionuclides for radioimmunotherapeutic applications, the lack of gamma rays in its decay complicates the estimation of radiation dose since its biodistribution cannot be accurately determined by external imaging. A limited clinical trial has been conducted with tracer doses (1 mCi) of 90Y in five patients who then received second-look surgery such that tissue samples were obtained for accurate radioactivity quantitation by in vitro counting. The anti-ovarian antibody OC-125 as the F(ab')2 fragment was coupled with diethylenetriaminepentaacetic acid, radiolabeled with 90Y and administered intraperitoneally to patients with suspected or documented ovarian cancer. Size exclusion and ion exchange high performance liquid chromatography analysis of patient ascitic fluid and serum samples showed no evidence of radiolabel instability although a high molecular weight species (presumably immune complex) was observed in three patients. Total urinary excretion of radioactivity prior to surgery averaged 7% of the administered radioactivity while at surgery the mean organ accumulation was 8% of the administered radioactivity in serum, 10% in liver, 7% in bone marrow, and 19% in bone with large patient to patient variation. The mean tumor/normal tissue radioactivity ratio varied between 3 and 25. On the assumption that the above radioactivity levels were achieved immediately following administration, that the radioactivity remained in situ until decayed and that the dimensions of tumor were sufficient to completely attenuate the emissions of 90Y, the dose to tumor for a 1-mCi administration would be approximately 50 rad with normal tissues receiving approximately 8 rad. PMID:3404257

  11. Luminol/antibody labeled gold nanoparticles for chemiluminescence immunoassay of carcinoembryonic antigen

    International Nuclear Information System (INIS)

    A facile strategy by loading luminol and secondary antibody on gold nanoparticles (Au NPs) was described in the present work. The as-prepared luminol/antibody labeled Au NPs conjugates (LAAu NPs) were used as the chemiluminescent probe for the detection of carcinoembryonic antigen (CEA) in serum. The LAAu NPs were characterized by transmission electron microscopy (TEM), UV-vis spectrophotometry (UV-vis), and chemiluminescent method. Stable and efficient chemiluminescence (CL) was obtained when luminol molecules and secondary antibodies were coimmobilized on the Au NPs by using hydrogen peroxide (H2O2) as an oxidant, horseradish peroxidase (HRP) as a catalyst, and 4-(4'-iodo)phenylphenol (IPP) as an enhancer. The LAAu NPs were further evaluated via a sandwich-type CL immunoassay of CEA in serum. In this protocol, the CEA analyte was captured by the primary antibody immobilized on the surface of magnetic beads, and then was sandwiched by the secondary antibody loaded on luminol-labeled Au NPs. The chemiluminescent intensity was proportional to the concentration of CEA over the range of 5.0 x 10-10 to 5.0 x 10-8 g mL-1 and 5.0 x 10-9 to 2.0 x 10-8 g mL-1 by using HRP and Co2+ as catalysts, respectively. The present chemiluminescent immunoassay based on the luminol/antibody labeled Au NPs conjugates has offered great promise for simple, highly biocompatible, and cost-effective analysis of biological samples.

  12. Detection of osteomyelitis using a Tc-99m labeled antigranulocyte antibody immunoscintigraphy

    International Nuclear Information System (INIS)

    The purpose of this study was to evaluate the diagnostic accuracy of Tc-99m labeled antigranulocyte antibody immunoscintigraphy in the diagnosis of osteomyelitis and compare with the results of triphasic bone scan. The study population was 39 patients (22 male, 17 female) who had uncertain diagnoses of osteomyelitis. Fifteen patients had history of orthopedic surgery, and 5 had previous fracture. One milligram of monoclonal antibody against NCA-95 was labeled with 370 MBq of Tc-99m, injected intravenously, and 4 hour images were obtained. Triphasic bone scan images were obtained in 30 patients. The final diagnosis was confirmed by bacteriologic culture, biopsy or long term clinical follow up. Twenty one patients were confirmed to have osteomyelitis (1 acute, 20 chronic). Eighteen patients were without osteomyelitis. Antigranulocyte antibody immunoscintigraphy had a sensitivity of 71% (15/21), and a specificity of 89% (16/18), while the sensitivity and specificity of triphasic bone scan was 93% (13/14) and 38% (6/16), respectively. Antigranulocyte antibody scan showed higher specificity of 100% (11/11) in comparison with 33% (3/9) of triphasic bone scan in patients with history of orthopedic surgery or fracture. Antigranulocyte antibody immunoscintigraphy is more specific than that of triphasic bone scan and may be helpful in patients with history of surgery or fracture. However, sensitivity is lower than triphasic bone scan in the detection of chronic osteomyelitis

  13. Production of antibody labeled gold nanoparticles for influenza virus H5N1 diagnosis kit development

    International Nuclear Information System (INIS)

    Preparation of colloidal gold conjugated antibodies specific for influenza A/H5N1 and its use in developing a virus A/H5N1 rapid diagnostic kit is presented. Colloidal gold nanoparticles (AuNPs) were prepared through citrate reduction. Single chain antibodies specific to H5N1 (scFv7 and scFv24) were produced using pTI2 + vector and E. coli strain HB2151. These antibodies were purified by affinity chromatography technique employing HiTrap Chelating HP columns pre-charged with Ni2 + . The method for preparation of antibody–colloidal gold conjugate was based on electrostatic force binding antibody with colloidal gold. The effect of factors such as pH and concentration of antibody has been quantitatively analyzed using spectroscopic methods after adding 1 wt% NaCl which induced AuNP aggregation. The morphological study by scanning electron microscopy (SEM) showed that the average size of the spherical AuNPs was 23 nm with uniform sizes. The spectroscopic properties of colloidal AuNPs showed the typical surface plasmon resonance band at 523 nm in UV-visible spectrum. The optimal pH of conjugated colloidal gold was found between 8.0 and 10.0. The activity of synthesized antibody labeled AuNPs for detection of H5N1 flu virus was checked by dot blot immunological method. The results confirmed the ability in detection of the A/H5N1 virus of the prepared antibody labeled gold particles and opened up the possibility of using them in manufacturing rapid detection kit for this virus. (paper)

  14. Sequential imaging of indium-111-labeled monoclonal antibody in human mammary tumors hosted in nude mice

    International Nuclear Information System (INIS)

    Using a bifunctional chelating agent, indium-111 was attached to a monoclonal antibody 10-3D2, specific for a 126-kilodalton phosphoglycoprotein antigen associated with human mammary carcinoma, and was then used to localize and visualize human mammary tumors hosted in nude mice. Simultaneous tumor concentration of In-111-10-3D2 was eight times greater than that of control I-125-MOPC-21. Uptake of F(ab')2 and Fab of 10-3D2 was also compared. The scintigrams demonstrated that intact antibody provided the best images. Control In-111-labeled MOPC-21 and plasma did not show specific localization in the tumor. Uptake of In-111-labeled 10-3D2 was also compared in two lines of human mammary tumors, BT-20 and HS-578T. Imaging with 10-3D2 was better for BT-20 than for HS-578T

  15. Dye Labelled Monoclonal Antibody Assay for Detection of Toxic Shock Syndrome Toxin -1 from Staphylococcus Aureus

    Directory of Open Access Journals (Sweden)

    V Javid Khojasteh

    2011-12-01

    Full Text Available Objective: The aim of study was to develop a rapid assay, dye labelled monoclonal antibody assay (DLMAA, using non-radioactive organic synthetic dyes for identification of Toxic Shock Syndrome Toxin-1 (TSST-1 producing strains of Staphylococcus aureus.Materials and Methods: The assay protocol required only two simple steps; addition of TSST-1 antigen to a nitrocellulose membrane and then adding a colloidal dye labelled antibody (D/A suspension detection reagent.Results: The sensitivity and specificity of the assay was determined relative to positive and negative strains compared to an ELISA assay. Overall 100% agreement was found between both assays. The sensitivity for detection of TSST-1 was 30 ng.Conclusion: The DLMAA did not require handling and disposal of radioactive materials. It is a rapid qualitative technique for detection of TSST-1 toxin at room temperature within a short time.

  16. Radiation exposure of the patient due to nuclear medical application of labeled monoclonal antibodies

    International Nuclear Information System (INIS)

    The aim of this work was an assessment of the radiation dose to the patient as a result of radioimmunoscintigraphy. The assessment was carried out on the basis of biokinetics measurements of the monoclonal antibodies CA 19-9/anti-CEA, anti-CEA, Ca 125, antimelanoma, antimyosin, labeled with I-131, In-111 or Tc-99m. Whole-body retention, organ uptake and organ retention were measured in the whole-body counter and at the gamma camera in 165 patients applying the technique of the geometrical means. The effective dose equivalent for I-131-labeled antibodies was 30 mSv (in the case of 115 MBq of applied activity). The thyroid gland dose was 434 mGy in the case of perchlorate blocking, with the badly tolerated blocking with 0.5 g KJ tablets it was 133 mGy, and in the case of a combination of both, 199 mGy (2 days KJ, after this perchlorate). Labeling of the antibodies with In-111 resulted in a similarly high effective dose equivalent of 34 mSv 130 MBq of applied activity. The mean kidney dose was 124 mGy. Only labeling with Tc-99m achieves a clear reduction of the effective dose equivalent to about 7 mSv. The doses to the most exposed organs were 63 mGy kidney dose (in the case of antimelanoma), and 18 mGy liver dose (with anti-CEA-antibodies). The radiation exposure of the patients due to radioimmunoscintigraphy is above the dose values of most of the other nuclear medical examination techniques. (orig./HP)

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

    International Nuclear Information System (INIS)

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

  18. Technetium-99m labelling of the ior-CEA-1 monoclonal antibody: Evaluation of different methods

    International Nuclear Information System (INIS)

    In the present work, we evaluated the influence of experimental conditions on the characteristics of the radiolabelled ior-CEA-1 prepared by direct method, using 2-ME and stannous chloride as reductants and indirect method in which 2-IM is used to generate sulfhydryl groups in the protein. The following parameters were studied: number of free sulfhydryl groups of treated antibody, labelling efficiency, chemical and radiochemical composition of the radiolabelled antibodies as well as their immunological and biological properties. The properties of 99Tcm-ior-CEA-1 obtained by 2-ME method were compared to the ones of the 99Tcm-monoclonal antibody obtained from a commercial kit (BW 431/26). Some clinical studies using 99Tcm-ior-CEA-1 were also performed

  19. Antibody and DNA dual-labeled gold nanoparticles: Stability and reactivity

    Science.gov (United States)

    Qiao, Fei-Yan; Liu, Jun; Li, Fu-Rong; Kong, Xiao-Li; Zhang, Hao-Li; Zhou, Han-Xin

    2008-03-01

    Gold nanoparticles labeled by both antibody (IgG) and single stranded DNA (ss-DNA) have been synthesized and characterized. The stability and reactivity of the dual-labeled nanoparticles were compared with the conventional IgG or ss-DNA modified nanoparticles. It was found that the IgG adsorption significantly improved the stability of the nanoparticles in aqueous solution, which is beneficial for attaching ss-DNA. The presence of IgG also effectively prohibits the desorption of ss-DNA against dithiothreitol (DTT) displacement. The coverage on dual-labeled nanoparticles was found to be 50 ± 15 ss-DNA/nanoparticle and 10 ± 2 IgG/nanoparticle, respectively, compared to the value of 70 ± 15 ss-DNA/nanoparticle of only ss-DNA-labeled gold nanoparticles. Dot-immuno and cross-linking experiments confirmed that both the IgG and ss-DNA retained their bioactivity on the nanoparticle surface. The dual-labeled nanoparticles have potential to be used as novel bio-probes for ultrasensitive detection.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1993-01-01

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

  1. Antibody labelling of resilin in energy stores for jumping in plant sucking insects.

    Science.gov (United States)

    Burrows, Malcolm; Borycz, Jolanta A; Shaw, Stephen R; Elvin, Christopher M; Meinertzhagen, Ian A

    2011-01-01

    The rubbery protein resilin appears to form an integral part of the energy storage structures that enable many insects to jump by using a catapult mechanism. In plant sucking bugs that jump (Hemiptera, Auchenorrhyncha), the energy generated by the slow contractions of huge thoracic jumping muscles is stored by bending composite bow-shaped parts of the internal thoracic skeleton. Sudden recoil of these bows powers the rapid and simultaneous movements of both hind legs that in turn propel a jump. Until now, identification of resilin at these storage sites has depended exclusively upon characteristics that may not be specific: its fluorescence when illuminated with specific wavelengths of ultraviolet (UV) light and extinction of that fluorescence at low pH. To consolidate identification we have labelled the cuticular structures involved with an antibody raised against a product of the Drosophila CG15920 gene. This encodes pro-resilin, the first exon of which was expressed in E. coli and used to raise the antibody. We show that in frozen sections from two species, the antibody labels precisely those parts of the metathoracic energy stores that fluoresce under UV illumination. The presence of resilin in these insects is thus now further supported by a molecular criterion that is immunohistochemically specific. PMID:22163306

  2. Antibody labelling of resilin in energy stores for jumping in plant sucking insects.

    Directory of Open Access Journals (Sweden)

    Malcolm Burrows

    Full Text Available The rubbery protein resilin appears to form an integral part of the energy storage structures that enable many insects to jump by using a catapult mechanism. In plant sucking bugs that jump (Hemiptera, Auchenorrhyncha, the energy generated by the slow contractions of huge thoracic jumping muscles is stored by bending composite bow-shaped parts of the internal thoracic skeleton. Sudden recoil of these bows powers the rapid and simultaneous movements of both hind legs that in turn propel a jump. Until now, identification of resilin at these storage sites has depended exclusively upon characteristics that may not be specific: its fluorescence when illuminated with specific wavelengths of ultraviolet (UV light and extinction of that fluorescence at low pH. To consolidate identification we have labelled the cuticular structures involved with an antibody raised against a product of the Drosophila CG15920 gene. This encodes pro-resilin, the first exon of which was expressed in E. coli and used to raise the antibody. We show that in frozen sections from two species, the antibody labels precisely those parts of the metathoracic energy stores that fluoresce under UV illumination. The presence of resilin in these insects is thus now further supported by a molecular criterion that is immunohistochemically specific.

  3. Localization of pulmonary human sarcoma xenografts in athymic nude mice with indium-111-labeled monoclonal antibodies

    International Nuclear Information System (INIS)

    In order to study localization of metastatic tumors with a radiolabeled monoclonal antibody, a pulmonary metastases model was devised in athymic mice. Metastatic pulmonary sarcoma colonies were verified by histological examination. A murine monoclonal antibody (MAb 19-24) directed against a human sarcoma antigen was labeled with indium-111 (111In) by use of the linker 1-(p-isothiocyanatobenzyl)-diethylenetriaminepentaacetic acid (SCN-Bz-DTPA). MAb P3 was similarly labeled as a negative control. In the group given MAb 19-24, the percent injected dose per gram lung tissue bearing tumor colonies (30.1%, 29.6%, and 27.7% on Days 1, 2, and 3, respectively) was significantly (p less than 0.05) higher than in those receiving MAb P3. Hepatic activities of both 111In-MAb 19-24 and 111In-MAb P3 were low. The lungs with tumor colonies demonstrated clearest images on Day 3. The specific binding of 111In-SCN-Bz-DTPA-labeled MAb 19-24 to pulmonary xenografts without appreciable liver uptake indicates that it may be useful in the clinical localization of pulmonic metastatic lesions

  4. Labeling an anti-CD20 monoclonal antibody with 90Y

    International Nuclear Information System (INIS)

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

  5. Boron labeled rabbit anti-rat fibrin and goat anti-rabbit gamma globulin antibodies and their potential for slow neutron capture therapy of tumors

    International Nuclear Information System (INIS)

    The therapeutic effectiveness of slow neutron capture therapy is currently dependent upon achieving a high concentration gradient of boron between tumor and normal tissue. Labeling of anti-tumor or anti-tumor site antibodies with boron containing compounds could provide this high therapeutic value. Anti-rat fibrin antibodies, which show considerable localization at the site of several transplantable rat tumors, were labeled with 4-boronophenylalanine (4-BPA) using the N-carboxy anhydride procedure. Activity of these labeled antibodies was studied by modifying the test for fibrinogen concentration of hemophiliac blood. The number of 4-BPAs bound to each active antibody was determined indirectly using the fluorimetric test for phenylalanine concentration in serum. These tests showed that labeled antibodies retained their activity, and it was possible to add up to fifty 4-BPAs per active antibody. The indirect approach to achieving a high therapeutic value of boron was also investigated. This procedure involves labeling anti-immunoglobulin antibodies that bind to anti-tumor antibodies which are already bound to their respective antigens. Indirect labeling has the potential of increasing the therapeutic value by a factor of ten over the direct approach. Activity of labeled goat anti-rabbit gamma globulin (RGG) antibodies was studied by radial immunodiffusion and passive hemagglutination. The number of 4-BPAs bound to each active antibody was determined indirectly by fluorimetry. These labeled antibodies also retained their activity, and it was possible to add upwards of forty 4-BPAs per active antibody

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

    Energy Technology Data Exchange (ETDEWEB)

    Murthy, S.; Sharkey, R.M.; Goldenberg, D.M.; Lee, R.E.; Pinsky, C.M.; Hansen, H.J.; Burger, K.; Swayne, L.C. (Center for Molecular Medicine and Immunology, Newark, NJ (United States) Garden State Cancer Center, Newark, NJ (United States) Immunomedics, Inc., Warren, NJ (United States) University Hospital, UMDNJ, Newark, NJ (United States). Dept. of Radiology Morristown Memorial Hospital, NJ (United States))

    1992-06-01

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

  7. Experimental radioimmunotherapy of a xenografted human glioma using 131I-labeled monoclonal antibody to epidermal growth factor receptor

    International Nuclear Information System (INIS)

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

  8. Evaluation of indium-111-labeled anti-fibrin antibody for imaging vascular thrombi

    International Nuclear Information System (INIS)

    Monoclonal antibody 59D8 developed by Hui et al., binds to fibrin but not fibrinogen. An 111In-labeled Fab fragment of 59D8 was studied in vitro and in animal models to evaluate its potential for imaging thrombi and emboli in man. Rabbits and dogs were used as models for studying thrombus uptake in vivo. Thrombi and emboli up to 4 days old were successfully visualized at 4-24 hr postinjection in five of eight rabbits. In dogs, 0.5-hr-old and 24-hr-old thrombi were successfully imaged at 24 hr in six of eight animals, and 3/6 of these were positive at 3-4 hr postinjection. Thrombus-to-blood ratios in the dogs averaged 7.1 +/- 1.3. The findings suggest this antibody may be useful for imaging thrombi in man

  9. Developing a Noninvasive Procedure Using Labeled Monoclonal Antibody Anti-VEGF (Bevacizumab for Detection of Endometriosis

    Directory of Open Access Journals (Sweden)

    Daniel Escorsim Machado

    2015-01-01

    Full Text Available The off-label use of bevacizumab labeled with 99mTc as a new radiopharmaceutical for imaging of endometriosis is a promising noninvasive, new clinical procedure. The bevacizumab in monoclonal antibodies targeted at vascular endothelial growth factor (VEGF is superexpressed in cases of endometriosis. In this study we evaluate the imaging of endometriosis lesion in rats (induced to endometriosis using bevacizumab-99mTc. The results showed that bevacizumab-99mTc imaged the lesion and support his use for Nuclear Medicine applied to gynecology. Also the results appointed that this radiopharmaceutical has a hepatobiliary excretion. It is important to notice that the dose used was almost 0,01% of the usual dose for the bevacizumab.

  10. Radiation doses obtained from 99mTc-labelled human milk fat globule monoclonal antibodies

    International Nuclear Information System (INIS)

    Human milk fat globule (HMFG) monoclonal antibodies labelled with 123I and 111In are used for the diagnosis of ovarian and breast cancer. Methods have been developed to label HMFG with 99mTc and this study reports on the subsequent radiation dose delivered. The 99mTc HMFG1 distribution was obtained in 5 normal female baboons up to 71 h after administration. The liver, kidneys, bladder and whole body were identified as source organs and total absorbed doses for the target organs were 0.054 (kidneys), 0.013 (liver), 0.140 (bladder), 0.010 (ovaria), 0.004 (bone marrow), 0.002 (thyroid), 0.003 (heart wall), 0.017 (uterus) and 0.005 mGy/MBq (whole body). The effective dose was 0.014 mSv/MBq. (author)

  11. Radiation doses obtained from 99mTc-labelled human milk fat globule monoclonal antibodies

    International Nuclear Information System (INIS)

    Human milk fat globule (HMFG) monoclonal antibodies labelled with 125I and 111In are used for the diagnosis of ovarian and breast cancer. Methods have been developed to label HMFG with 99mTc and this study reports on the subsequent radiation dose delivered. The 99mTc HMFG1 distribution was obtained in 5 normal female baboons up to 71 h after administration. The liver, kidneys, bladder and whole body were identified as source organs and total absorbed doses for the target organs were 0.054 (kidneys), 0.013 (liver), 0.140 (bladder), 0.010 (ovaria), 0.004 (bone marrow), 0.002 (thyroid), 0.003 (heart wall), 0.017 (uterus) and 0.005 mGy/MBq (whole body). The effective dose was 0.014 mSv/MBq. (author)

  12. A radioimmunoassay for virus antibody using binding of 125I-labelled protein A

    International Nuclear Information System (INIS)

    An assay for virus antibodies using protein A from Staphylococcus aureus is described. Type B and type C RNA tumour viruses adsorbed on to polystyrene microtitre plate wells were incubated with antiserum and then with 125I-labelled protein A (I-pA) and bound radioactivity was determined. Technical details such as labelling, antigen concentration, storage of I-pA are reported. The specificity of the reaction was investigated in detail by competition experiments with purified unbound homologous viruses. This assay also proved to be sensitive for demonstration of autogenous immunity to both type B and type C RNA tumour viruses. A study using antisera against purified core and envelope virus proteins of mammary tumour and leukaemia viruses suggested that the reaction mainly involves surface antigens of the intact virions. (author)

  13. Positron Emission Tomography Imaging of Tumor Angiogenesis with a 66Ga-Labeled Monoclonal Antibody

    OpenAIRE

    Engle, Jonathan W.; Hong, Hao; Zhang, Yin; Valdovinos, Hector F.; Myklejord, Duane V.; Barnhart, Todd E.; Theuer, Charles P.; Robert J. Nickles; Cai, Weibo

    2012-01-01

    The goal of this study was to develop a 66Ga-based positron emission tomography (PET) tracer for non-invasive imaging of CD105 expression during tumor angiogenesis, a hallmark of cancer. 66Ga was produced using a cyclotron with natZn or isotopically enriched 66Zn targets. TRC105, a chimeric anti-CD105 monoclonal antibody, was conjugated to 2-S-(4-isothiocyanatobenzyl)-1, 4, 7-triazacyclononane-1, 4, 7-triacetic acid (p-SCN-Bn-NOTA) and labeled with 66Ga. No difference in CD105 binding affinit...

  14. Evaluation of {sup 111}In labeled antibodies for SPECT imaging of mesothelin expressing tumors

    Energy Technology Data Exchange (ETDEWEB)

    Misri, Ripen; Saatchi, Katayoun [Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, BC, V6T 1Z3 (Canada); Ng, Sylvia S.W. [Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, BC, V6T 1Z3 (Canada); Advanced Therapeutics, British Columbia Cancer Agency, Vancouver BC V5Z 1G1 (Canada); Kumar, Ujendra [Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, BC, V6T 1Z3 (Canada); Haefeli, Urs O., E-mail: uhafeli@interchange.ubc.ca [Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, BC, V6T 1Z3 (Canada)

    2011-08-15

    Introduction: Mesothelin is expressed in many cancers, especially in mesothelioma and lung, pancreatic and ovarian cancers. In the present study, we evaluate {sup 111}In labeled antimesothelin antibodies as an imaging bioprobe for the SPECT imaging of mesothelin-expressing tumors. Methods: We radiolabeled the antimesothelin antibodies mAbMB and mAbK1 with {sup 111}In using the p-SCN-bn-DTPA chelator. The immunoreactivity, affinity (K{sub d}) and internalization properties of the resulting two {sup 111}In labeled antibodies were evaluated in vitro using mesothelin-expressing A431K5 cells. The biodistribution and microSPECT/CT imaging studies with {sup 111}In labeled antibodies were performed in mice bearing both mesothelin positive (A431K5) and mesothelin negative (A431) tumors. Results: In vitro studies demonstrated that {sup 111}In-mAbMB bound with a higher affinity (K{sub d}=3.6{+-}1.7 nM) to the mesothelin-expressing A431K5 cells than did the {sup 111}In-mAbK1 (K{sub d}=29.3{+-}2.3 nM). {sup 111}In-mAbMB was also internalized at a greater rate and extent into the A431K5 cells than was the {sup 111}In-mAbK1. Biodistribution studies showed that {sup 111}In-mAbMB was preferentially localized in A431K5 tumors when compared to A431 tumors. At the low dose, the peak A431K5 tumor uptake of 9.65{+-}2.65% ID/g (injected dose per gram) occurred at 48 h, while at high dose tumor uptake peaked with 14.29{+-}6.18% ID/g at 72 h. Non-specific localization of {sup 111}In-mAbMB was mainly observed in spleen.{sup 111}In-mAbK1 also showed superior localization in A431K5 tumors than in A431 tumors, but the peak uptake was only 3.04{+-}0.68% ID/g at 24 h. MicroSPECT/CT studies confirmed better visualization of A431K5 tumors with {sup 111}In-mAbMB, than with {sup 111}In-mAbK1. Conclusion: SPECT imaging of mesothelin expressing tumors was demonstrated successfully. Our findings indicate that the antimesothelin antibody mAbMB has the potential to be developed into a diagnostic agent

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

    International Nuclear Information System (INIS)

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

  16. Indirect labeling of monoclonal antibodies employing N2-diethylentriamine-pentaacetil lysine amide as 99mTc chelating agent

    International Nuclear Information System (INIS)

    Labeled monoclonal antibodies and their fragments are been widely employed for the diagnosis and follow up of different kinds of neoplasm. The aim of the present work was to develop a method for indirect labeling of antibodies with 99mTc, using N2-diethylentriamine-pentaacetil lysine amide as chelating agent. By reactions with a 200-fold molar excess of 2-iminothiolane, and the reduction using a 2000-fold molar excess of 2-mercaptoethanol, 3.5 ± 0.6 and 5.8 ± 0.5 sulfhydryl groups, respectively, were generated in the antibody. Thus, work was continued using the second procedure. Reduced h-R3 was incubated for 12 h with N6-cyclohexylmaleimide-N2-diethylentriamine-pentaacetil lysine amide, previously obtained by the reaction of N2-diethylentriamine-pentaacetil lysine amide with sodium sulfosuccinimidyl-4(N-maleimidomethyl)cyclohexane-1-carboxylate. Labeling efficiency of h-R3 monoclonal antibody, modified by this method with 99mTc, was (98.6 ± 1.4) %. A satisfactory stability of the label was observed up to 24 h in presence of a 300-fold molar excess of L-cysteine. Conclusions: Developed procedure allowed satisfactory indirect labeling of the humanized monoclonal antibody h-R3 with 99mTc, using N2-diethylentriamine-pentaacetil lysine amide as bifunctional chelating agent

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1982-03-01

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

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

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

  20. Detection of SHV β-lactamases in Gram-negative bacilli using fluorescein-labeled antibodies

    Directory of Open Access Journals (Sweden)

    Endimiani Andrea

    2009-03-01

    Full Text Available Abstract Background β-lactam resistance in Gram-negative bacteria is a significant clinical problem in the community, long-term care facilities, and hospitals. In these organisms, β-lactam resistance most commonly results from the production of β-lactamases. In Gram-negative bacilli, TEM-, SHV-, and CTX-M-type β-lactamases predominate. Therefore, new and accurate detection methods for these β-lactamase producing isolates are needed. Results E. coli DH10B cells producing SHV-1 β-lactamase and a clinical isolate of K. pneumoniae producing SHV-5 β-lactamase were rendered membrane permeable, fixed and adhered to poly-L-lysine coated slides, and stained with purified polyclonal anti-SHV antibodies that were fluorescein labeled. E. coli DH10B cells without a blaSHV gene were used as a negative control. The procedure generated a fluorescence signal from those slides containing cells expressing SHV β-lactamase that was sufficient for direct imaging. Conclusion We developed a rapid and accurate method of visualizing the SHV family of enzymes in clinical samples containing Gram-negative bacilli using a fluorescein-labeled polyclonal antibody.

  1. Comparative studies of antibody anti-CD20 labeled with 188Re

    International Nuclear Information System (INIS)

    Nuclear Medicine is an unique and important modality in oncology and the development of new tumor-targeted radiopharmaceuticals for both diagnosis and therapy is an area of interest for researchers. Rituximab (RTX) is a quimeric monoclonal antibody (mAb) (IgG 1) that specifically binds to CD20 antigen with high affinity and has been successfully used for the treatment of Non-Hodgkin Lymphoma (NHL) of cell B. The CD20 antigen is expressed over more than 90% of cell B NHL. Technetium-99m (99mTc) and rhenium-188 (188Re) are an attractive radionuclide pair for clinical use due to their favorable decay properties for diagnosis (99mTc: T1/2 = 6 h, γ radiation = 140 keV) and therapy (188Re: T1/2 = 17 h, maximum β energy = 2.12 MeV) and to their availability in the form of 99Mo/99mTc and 188W/188Re generators. The radionuclides can be conjugated to mAb using similar chemical procedures. The aim of this work was to study the labeling of anti-CD20 mAb (RTX) with 188Re using two techniques: the direct labeling method [188Re(V)] and the labeling method via the carbonyl nucleus [188Re(I)]. Besides the quality control, the radiolabeled mAb was submitted to in vivo, in vitro and ex vivo biological studies. For the direct labeling, RTX was reducing by incubation with 2-mercaptoethanol for generating sulphydryl groups (-SH) and further labeled with 188Re(V), in a study of several parameters in order to reach an optimized formulation. The labeling via the carbonyl nucleus both 99mTc and 188Re were employed through 2 different procedures: (1) labeling of intact RTX with 99mTc(I) and (2) reduced RTX (RTXred) labeled with 99mTc(I)/188Re(I). Also a parameter study was performed to obtain an optimized formulation. The quality control method for evaluating the radiochemical purity showed a good labeling yield (93%) for the direct method. The labeling method via carbonyl group, the results showed that the - SH groups of RTXred are a possible way of labeling. The formulation of 99m

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

    International Nuclear Information System (INIS)

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

  3. SPECT imaging of neuropilin receptor type-1 expression with 131I-labeled monoclonal antibody.

    Science.gov (United States)

    Dou, Xiaofeng; Yan, Jianghua; Zhang, Yafei; Liu, Peng; Jiang, Yizhen; Lv, Sha; Zeng, Fanwei; Chen, Xiaoli; Wang, Shengyu; Zhang, Haipeng; Wu, Hua; Zhang, Hong; Ouyang, Lin; Su, Xinhui

    2016-09-01

    As a novel co-receptor for vascular endothelial growth factor (VEGF), neuropilin receptor type-1 (NRP-1) is overexpressed in several cancers and metastases, and serves as an attractive target for cancer molecular imaging and therapy. Previous single photon emission computerized tomography (SPECT) studies demonstrated that the small NRP-1-targeting peptides 99mTc-MA-ATWLPPR and 99mTc-CK3 showed poor tumor imaging quality, because of their rapid blood clearance and very low tumor uptake. Compared with small peptides, monoclonal antibodies (mAbs) can improve imaging of NRP-1-expression, due to their high affinity, specificity and slow extraction. A6-11-26 is a novel monoclonal antibody against NRP-1 b1b2 domain that exhibits inhibition of tumor growth in NPR-1-expressing preclinical models. The aim of the present study was to develop the 131I-labeled anti-NRP-1 monoclonal antibody A6-11-26 as a SPECT probe for imaging of NRP-1-positive tumor. An anti-NRP-1 monoclonal antibody (A6-11-26) was produced by hybridomas and was labeled with iodine-131 by the iodogen method. In vitro, the radiolabeling efficiency, radiochemical purity, immunoreactive fraction and stability were assessed. Binding affinity and specificity of 131I‑A6-11-26 to NRP-1 were evaluated using human glioblastoma U87MG cells. In vivo, biodistribution and SPECT/CT studies were conducted on mice bearing U87MG xenografts after the injection of 131I-A6-11-26 with or without co-injection of unlabeled A6-11-26 antibody. A6-11-26 was generated successfully by hybridoma with high purity (>95%) and was labeled with iodine-131 within 60 min with high labelling efficiency (95.46±3.34%), radiochemical purity (98.23±1.41%). 131I-A6-11-26 retained its immunoreactivity and also displayed excellent stability in mouse serum and PBS solution during 1 to 96 h. Cell uptake assays showed high NRP-1-specific uptake (15.80±1.30% applied activity at 6 h) in U87MG cells. 131I-A6-11-26 bound to NRP-1 with low nanomolar

  4. Labelling of biorelated compounds and monoclonal antibodies with 188-Re,186-Re and 99mTc

    International Nuclear Information System (INIS)

    Some bio-related compounds were labelled with 188Re and 186Re 188Re was obtained from 188W/188Re generator which was produced by neutron irradiation of enriched 186WO3 target (99.79%) in JRR-2 and 186Re was supplied by Production Div., Department of Radioisotopes, JAERI, Japan. Rhenium labelling involved reduction of perrhenate with SnCl2.2H20 in HCI. Bio-related compounds citrate and gluconate were then labelled with reduced rhenium. The labelling yield of labelled compounds as determined by thin-layer chromatography were greater than 98% and 94% for 188Re-citrate and gluconate, respectively. Monoclonal antibodies (mouse,lgG2A and lgG;Fab'2, human lgG2A; anti-hepatoma and IgG) were also successfully labelled with 188Re, 186Re, and 99mTc by direct method using citrate and glucoheptonate as transchelating agents

  5. Introduction of new derivatives of biotin and DTPA for labeling of antibodies with 111 In ti detect malignant tumors

    International Nuclear Information System (INIS)

    Radiolabeled monoclonal antibodies, have created new innovations in diagnosis, research, and therapy of diseases in last 2 decades. One of the serious limitations of applications of radiolabeled antibodies in vivo is relatively low target to background activity. Various strategies have been proposed to solve this problem including pre-targeting methods that was suggested in 1989. Regarding importance of monoclonal antibodies and radioisotopes, based on pre-targeting strategy, we have introduced new derivative of biotin and DTPA to decrease background activity. DTPA-bio and new derivative (DTPA-bio-1 OX) were labeled with 111 In, labeled compounds and injected through tail veins into Balb/c mice, and percent of injected dose per gram of blood (% ID/g of blood ) was determined at 15, 30, 60, 120, 180 and 240 min after injection. Based on results, 111 In-DTPA-bio rapidly cleared from serum, indicating activity not bound to the target. While in the case of new derivative, by attaching 10 Adenine base (IOX) molecular weight of label is increased causing delayed clearance from serum. Therefore, there is enough time for label to accumulate in the target tissues. With advent of second generation of monoclonal antibodies and antibody engineering, pre targeting methods have changed greatly. It seems that derivatives we introduced will have and important role in new pre-targeting methods

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

    International Nuclear Information System (INIS)

    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. 99mTc 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 99mTc. 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 Sn2+, 1 mL of 99mTc and 30 min. reaction time. With these conditions the labelling yield was always higher than 95% and the maximum activity of 99mTc was about 2220 MBq (60 mCi). The evidences of the efficiency and quality of the methods here

  7. Prospective study of 123I-labeled monoclonal antibody imaging in ovarian cancer

    International Nuclear Information System (INIS)

    Thirty patients presenting with a pelvic mass were entered into a prospective study on the use of radioimmunoscintigraphy with the 123I-labeled monoclonal antibody HMFG2. The imaging data was obtained without knowledge of the clinical data and compared with subsequent surgical findings. A false-positive diagnosis of ovarian cancer was made in five of ten patients subsequently shown not to have ovarian cancer; thus the technique cannot be used as a screening test. A true-positive diagnosis was made in 19 out of 20 patients shown subsequently to have ovarian cancer. In 18 of these patients the distribution of uptake closely fitted the surgical findings. Methods of improving these results are described. In conclusion, radioimmunoscintigraphy is of no use in determining whether a pelvic mass is due to ovarian cancer, but has benefit in the evaluation of chemotherapy and may, in the future, prevent the need for second-look operations in some circumstances

  8. Radioimmunodetection with 111In-labeled monoclonal antibody Nd2 in patients with pancreatic cancer

    International Nuclear Information System (INIS)

    This report summarizes results from an initial clinical evaluation of radioimmunodetection (RAID) in patients with pancreatic cancer using murine monoclonal antibody Nd2, directed against mucins from pancreatic cancer. Nd2 (2 mg) was labeled with 111In (2 mCi) and injected into 19 patients suspected of having pancreatic cancer. Planar scintigrams were taken 3 days post-infusion. As for final diagnoses after surgery, 14 cases were pancreatic cancer, and one case each was chronic pancreatitis, neurilemmoma, islet cell carcinoma, cholangioma, and apparent absence of suspected recurrent lesion of pancreatic cancer. Of 14 patients with pancreatic cancer, RAID was positive in 10 cases (71.4%). Cases other than pancreatic cancer were all negative, so the specificity was 100%. These results demonstrate that RAID using 111In-Nd2 can be useful in differentiating exocrine pancreatic cancer from benign conditions and other types of carcinomas in the pancreatoduodenal regions. (author)

  9. Technetium-99m labelling of the IOR CEA 1 monoclonal antibody: evaluation of different methods

    Energy Technology Data Exchange (ETDEWEB)

    Gano, L.; Fernandes, C.; Patricio, L. [Inst. Tecnologico Nuclear, Sacavem (Portugal); Cantinho, G.; Santos, A.I.; Pena, H. [F.M.L., Lisboa (Portugal). Inst. Medicina Nuclear; Vieira, R.; Salgado, L. [IPOFG, Lisboa (Portugal). Servico Medicina Nuclear

    1997-09-01

    Aim: The aim of this study was to investigate the in vivo and in vitro properties of {sup 99m}Tc labelled monoclonal antibody, IOR CEA 1 when radiolabelled by different methods. Methods: To achieve that purpose IOR CEA was directly radiolabelled via 2-mercaptoethanol (2-Me) and stannous ion (SnCl{sub 2}) reduction and indirectly via the 2-iminothiolane (2-Im) conjugation. The resulting {sup 99m}Tc-MoAbs were analysed for number of free sulfhydryl groups, chemical and radiochemical purity (checked by HPLC and SDS PAGE), immunoreactivity and biological distribution in mice. Results: Experimental results indicated a similar radiochemical purity and immunoreactivity for direct labelling methods and a decrease of both for 2-Im method. 2-Me antibody reduction led to a high antibody fragmentation as indicated by non-denaturing SDS PAGE analysis. Nevertheless SnCl{sub 2} and 2-Im labels revealed lower in vivo stability. Conclusion: {sup 99m}Tc-(2-Me) IOR CEA presented favourable in vitro and in vivo properties. Therefore this label was compared to {sup 99m}Tc-monoclonal antibody BW 431/26. Similar characteristics were found. Clinical studies also revealed identical biodistribution profile. (orig.) [Deutsch] Ziel: Ziel der vorliegenden Studie war die Untersuchung der in vitro und in vivo Eigenschaften Technetium-markierter monoklonaler Antikoerper. Methoden: Hierzu wurde IOR CEA 1 entweder direkt, nach Reduktion mit 2-Mercaptoethanol (2-Me) bzw. Zinn(II)chlorid (SnCl{sub 2}), oder indirekt nach Konjugation mit 2-Iminothiolan (2-Im) markiert. Die Integritaet des reduzierten bzw. konjugierten Antikoerpers wurde mittels Bindungsassays und Elektrophorese ermittelt. Die radiochemischen Ausbeuten bzw. Reinheiten wurden chromatographisch bestimmt. Die pharmakokinetischen Eigenschaften von {sup 99m}Tc-IOR CEA 1 wurden tierexperimentell im Vergleich zu {sup 99m}Tc-BW 431/26 ermittelt. In einer ersten Studie wurden {sup 99m}Tc-(2-Me-)IOR CEA 1 und {sup 99m}Tc-BW 431/26 verglichen

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1983-10-14

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

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

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

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

    Directory of Open Access Journals (Sweden)

    M. Klein

    2013-01-01

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

  14. In vivo evaluation of a lead-labeled monoclonal antibody using the DOTA ligand

    International Nuclear Information System (INIS)

    The aim of this study was to assess the utility of a radioimmunoconjugate containing a lead radionuclide for therapy and scintigraphy applications. The radioimmunoconjugate evaluated consisted of a bifunctional DOTA ligand and monoclonal antibody (MAb) B72.3 using athymic mice bearing LS-174T tumors, human colon carcinoma xenografts. In the studies reported here, the lead-203-DOTA complex itself was first demonstrated to have in vivo stability. MAb B72.3 was then conjugated with the DOTA ligand and labeled with 203Pb, and the immunoreactivity of B72.3 was maintained. The localization of the radioimmunoconjugate to tumor tissue and other select organs paralleled that of DOTA-125I-B72.3, suggesting a similar metabolic pattern of the two radioimmunoconjugates. Thus, the DOTA-metal complex does not alter the behavior of the radioimmunoconjugate. Tumor localization of the 203Pb-DOTA-B72.3 conjugate was demonstrated with biodistribution studies as well as immunoscintigraphy studies. Such data highlight the stability of a lead radionuclide in the DOTA ligand. The suitability of this chelation chemistry for labeling radioimmunoconjugates with a lead radionuclide now makes its application in nuclear medicine a feasible proposition. (orig.)

  15. Preliminary studies of Technetium-99m-labeled antimyosin monoclonal antibody: development of radiopharmaceutical for cardiac evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Guilherme Luiz de Castro; Spencer, Patrick Jack; Muramoto, Emiko; Araujo, Elaine Bortoleti de [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: glcarval@ipen.br

    2007-07-01

    In the acute myocardium infarction, the myocytes cell membrane loses its integrity, allowing the influx of extracellular macromolecules such as circulating antibody into the damaged cell. Specific antibodies to cardiac myosin can therefore bind to the acutely necrotic myocyte, allowing the noninvasive localization and dimension of myocardial infarction. Because of its favorable physical characteristics, low cost, and ready availability, technetium-99m ({sup 99m}Tc) is the radionuclide of choice for scintigraphy. The purpose of this work was to study the labeling of the antimyosin monoclonal antibody with ({sup 99m}Tc for development of a radiopharmaceutical with high sensitivity and specificity used in the diagnostic of the myocardial infarction. The intact monoclonal antibody (IgG{sub 1}) was reduced by treatment with dithiothreitol (DTT) with the consequent generation of free thiol groups (- SH), responsible for the labeling of the antibody with ({sup 99m}Tc. The radiochemical yield was determined using Sephadex G-25 column (PD-10). The percentage of ({sup 99m}Tc-antibody was 90,06% and after purification procedure the radiochemical yield was > 98%. The biodistribution studies showed low uptake in the stomach and thyroid at different times (1, 4 e 24 hours) representing a small amount of unbounded ({sup 99m}Tc and a good stability of the purified ({sup 99m}Tc-antibody. The uptake in the normal heart was relatively low as expected. Based on these results, we concluded that the direct labeling procedure applied to the antimyosin monoclonal antibody allowed the easy preparation of the radiopharmaceutical with good stability to be used in the noninvasive diagnostic of the myocardial infarction. (author)

  16. Animal experiments in positive tumor scintigraphy based on the demonstration of clostridium rods using 131I-labelled antibodies

    International Nuclear Information System (INIS)

    Clostridial spores, applied i.v. to mice, grew out selectively to rods in transplanted tumors and could be demonstrated by 131I-labelled antibodies. An increased radioactivity was to be seen after additional application of Ig G. The decreased tumor activity compared to that of the blood depends probably on the inhibited blood flow of the tumor

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

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

  19. In vivo evaluation of an anti-melanoma antibody, F(ab')2, labelled with Tc-99m

    International Nuclear Information System (INIS)

    On the basis of the high specificity of the antigen-antibody reaction, tumor antigens can be recognized in vivo by specific antibodies, labelled with gamma emitting radionuclides (I-131, I-123, In-111, Tc-99m). Immunoscintigraphic detection of different human tumours has been obtained. A further improvement in the technique has been produced by the use of labelled purified FAb fragments, i.e. without Fc, the main cause of aspecific bonds. Divalent fragments, F(ab')2, have a better target/background ratio and show a faster clearance rate from the blood pool. Here we present our experience using Tc-99m-F(ab')2 of the 225.28S monoclonal antibody that recognizes high molecular weight melanoma associated antigens (HMW-MAA). (Auth.)

  20. In vivo SPECT/CT imaging of human orthotopic ovarian carcinoma xenografts with {sup 111}In-labeled monoclonal antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Huhtala, Tuulia [Department of Biotechnology and Molecular Medicine, University of Eastern Finland, P.O. Box 1627, FIN-70211 (Finland); Laakkonen, Pirjo [Department of Biotechnology and Molecular Medicine, University of Eastern Finland, P.O. Box 1627, FIN-70211 (Finland); Molecular Cancer Biology Research Program and Institute of Biomedicine, Biomedicum Helsinki, University of Helsinki, Helsinki (Finland); Sallinen, Hanna [Department of Biotechnology and Molecular Medicine, University of Eastern Finland, P.O. Box 1627, FIN-70211 (Finland); Ylae-Herttuala, Seppo [Department of Biotechnology and Molecular Medicine, University of Eastern Finland, P.O. Box 1627, FIN-70211 (Finland); Biocenter Kuopio, University of Kuopio, P.O. Box 1627, FIN-70211 Kuopio (Finland); Naervaenen, Ale, E-mail: ale.narvanen@uku.f [Department of Biotechnology and Molecular Medicine, University of Eastern Finland, P.O. Box 1627, FIN-70211 (Finland); Biocenter Kuopio, University of Kuopio, P.O. Box 1627, FIN-70211 Kuopio (Finland)

    2010-11-15

    Epidermal growth factor receptor (EGFR) and vascular endothelial growth factor receptor 3 (VEGFR-3) are expressed in the tumor area during the progression of ovarian carcinoma. Monoclonal antibodies developed against these receptors are potential diagnostic molecules for in vivo imaging of ovarian carcinoma. Methods: Biodistribution of the monoclonal antibodies cetuximab against EGFR and mF4-31C1 against VEGFR-3 was studied in nude mice with orthotopic SKOV-3m human ovarian carcinoma xenografts. The biodistribution of {sup 111}Indium-labeled antibodies was followed up to 48 h postinjection using combined SPECT and CT imaging modality. Organ samples were collected postmortem and specific organ activity was measured. Accumulation of the intravenously injected antibodies in the tumor tissue and lymph nodes was verified using immunohistology. Results: Imaging studies with SPECT/CT showed clear accumulation of both antibodies into tumor area. The tumor uptake was 8.78{+-}0.74 %ID/g for cetuximab and 5.77{+-}0.62 %ID/g for mF4-31C1 after 48 h postinjection. Cetuximab had lower liver tropism and faster tumor homing rate. In addition, after 48 h two of five tumor-bearing mice showed a clear accumulation of the In-labeled mF4-31C1 at the left axillary area. Both intravenously administered antibodies could also be detected from the tumor sections by immunohistological staining but only mF4-31C1 forms in the lymph nodes. Conclusion: These results demonstrate the accumulation of EGFR- and VEGFR-3-specific antibodies in orthotopic ovarian carcinoma tumors. Systemically administered they had slow pharmacokinetics which is typical for antibodies. Accumulation of mF4-31C1 antibody in the lymph nodes suggests the remote activation of VEGFR-3 by the primary tumor.

  1. Positron emission tomography imaging of tumor angiogenesis with a 66Ga-labeled monoclonal antibody.

    Science.gov (United States)

    Engle, Jonathan W; Hong, Hao; Zhang, Yin; Valdovinos, Hector F; Myklejord, Duane V; Barnhart, Todd E; Theuer, Charles P; Nickles, Robert J; Cai, Weibo

    2012-05-01

    The goal of this study was to develop a (66)Ga-based positron emission tomography (PET) tracer for noninvasive imaging of CD105 expression during tumor angiogenesis, a hallmark of cancer. (66)Ga was produced using a cyclotron with (nat)Zn or isotopically enriched (66)Zn targets. TRC105, a chimeric anti-CD105 monoclonal antibody, was conjugated to 2-S-(4-isothiocyanatobenzyl)-1,4,7-triazacyclononane-1,4,7-triacetic acid (p-SCN-Bn-NOTA) and labeled with (66)Ga. No difference in CD105 binding affinity or specificity was observed between TRC105 and NOTA-TRC105 based on flow cytometry analysis. Reactivity of (66)Ga for NOTA, corrected to the end of bombardment, was between 74 and 222 GBq/μmol for both target enrichments with 80% radiochemical yield. Serial PET imaging revealed that the murine breast cancer 4T1 tumor uptake of (66)Ga-NOTA-TRC105 was 5.9 ± 1.6, 8.5 ± 0.6, and 9.0 ± 0.6% ID/g at 4, 20, and 36 h postinjection, respectively (n = 4). At the last time point, tumor uptake was higher than that of all organs, which gave excellent tumor contrast with a tumor/muscle ratio of 10.1 ± 1.1. Biodistribution data as measured by gamma counting were consistent with the PET findings. Blocking experiment, control studies with (66)Ga-NOTA-cetuximab, as well as ex vivo histology all confirmed the in vivo target specificity of (66)Ga-NOTA-TRC105. Successful PET imaging with high specific activity (66)Ga (>700 GBq/μmol has been achieved) as the radiolabel opens many new possibilities for future PET research with antibodies or other targeting ligands. PMID:22519890

  2. Internal radiotherapy. 2. Treatment of non-hodgkin's lymphoma with 90Y-labeled anti-CD20 monoclonal antibody

    International Nuclear Information System (INIS)

    This paper describes recent trends of radioimmunotherapy using specific monoclonal antibodies against tumors, its principle and outcomes, with major emphasis on the title. When the antibodies like rituximab (rit), anti-CD20 antibody against B-cell malignant lymphoma, are labeled by a certain radioisotope, they become more active in specifically killing malignant cells by their immune cytotoxicity following binding plus lethal effect of radiation (beta ray). In Western areas, 90Y-labeled (ibritumomab, ibrit) or 131I-labeled rit is now available for the purpose. The efficacy of the former ibrit in the phase III trial has been reported to be 83%, in contrast to that of rit alone, 56%, with the similar safety to rit, in out-patients with the tumor. The protocol for the therapy is consisted from the first therapy with intravenous rit and imaging by 111In-labeled rit on day 1 and the second with the rit and ibrit (0.4 mCi/kg) on day 8. Patients are excluded from the latter therapy when the image by 111In shows the abnormal distribution in the liver and bone marrow. In Japan, phase I/II clinical trials of ibrit have been conducted to confirm its efficacy and safety and the agent is to be approved within this year. The radioimmunotherapy is thought to become more popular. (T.I.)

  3. Radioiodinated antibody targeting of the HER-2/neu oncoprotein: effects of labeling method on cellular processing and tissue distribution

    Energy Technology Data Exchange (ETDEWEB)

    Zalutsky, M.R. E-mail: zalut001@mc.duke.edu; Xu, F.J.; Yu, Y.; Foulon, C.F.; Zhao, X.-G.; Slade, S.K.; Affleck, D.J.; Bast, R.C

    1999-10-01

    Monoclonal antibody (MAb) internalization can have a major effect on tumor retention of radiolabel. Two anti-HER-2/neu MAbs (TA1 and 520C9) were radioiodinated using the iodogen, N-succinimidyl 5-iodo-3-pyridinecarboxylate (SIPC), and tyramine-cellobiose (TCB) methods. Paired-label studies compared internalization and cellular processing of the labeled MAbs by SKOv3 9002-18 ovarian cancer cells in vitro. Intracellular radioiodine activity for 520C9 was up to 2.6 and 3.0 times higher for SIPC and TCB labeling, respectively, compared with iodogen. Likewise, intracellular activity for TA1 was up to 2.3 and 2.9 times higher with the SIPC and TCB methods compared with iodogen labeling. Unfortunately, similar advantages in tumor accumulation were not achieved in athymic mice bearing SKOv3 9008-18 ovarian cancer xenografts.

  4. Radioiodinated antibody targeting of the HER-2/neu oncoprotein: effects of labeling method on cellular processing and tissue distribution

    International Nuclear Information System (INIS)

    Monoclonal antibody (MAb) internalization can have a major effect on tumor retention of radiolabel. Two anti-HER-2/neu MAbs (TA1 and 520C9) were radioiodinated using the iodogen, N-succinimidyl 5-iodo-3-pyridinecarboxylate (SIPC), and tyramine-cellobiose (TCB) methods. Paired-label studies compared internalization and cellular processing of the labeled MAbs by SKOv3 9002-18 ovarian cancer cells in vitro. Intracellular radioiodine activity for 520C9 was up to 2.6 and 3.0 times higher for SIPC and TCB labeling, respectively, compared with iodogen. Likewise, intracellular activity for TA1 was up to 2.3 and 2.9 times higher with the SIPC and TCB methods compared with iodogen labeling. Unfortunately, similar advantages in tumor accumulation were not achieved in athymic mice bearing SKOv3 9008-18 ovarian cancer xenografts

  5. 125I-labeled protein A as a general tracer in immunoassay: suitability of goat and sheep antibodies

    International Nuclear Information System (INIS)

    The immunoassay method in which 125I-labeled staphylococcal Protein A ([125I]PA) serves as a general tracer has been extended to include goat and sheep IgG antibodies. Goat and sheep IgG normally do not react significantly with PA. However, once IgG antibody is bound to immobilized antigen or hapten, binding of [125I]PA is enhanced markedly. Binding efficiencies of [125I]PA to immune complexed goat anti-human IgM, human IgE, methotrexate and sheep anti-IgE were determined and compared quantitatively to rabbit IgG with the corresponding specificity. Immunoassays were developed based on the inhibition of [125I]PA binding as a measure of antibody inhibition by fluid-phase homologous ligand. Goat antibody to the monovalent hapten methotrexate behaved anomalously: for each concentration of IgG tested, there was an optimal amount of methotrexate beads that gave maximum binding of [125I]PA. In the other immune systems, for each antibody concentration maximum binding of tracer was a function only of the amount of immobilized anitgen added. In contrast to the results obtained with solid-phase antigen, solutions containing antibody and amounts of antigen ranging from large antigen excess to antibody excess failed to react significantly with PA or [125I]PA. (Auth.)

  6. Preclinical Evaluation of 90Y Labelled Rituximab and ERIC-1: Two Antibodies for Tumour Therapy. Chapter 5

    International Nuclear Information System (INIS)

    The project described in this chapter focuses on harnessing the great potential of radionuclide therapy, using various vehicles to transport radionuclides into tumour tissues. The main aim of the project was to make specific vehicle molecules whose tumour affinity and suitability for radioactive coupling have been proven through laboratory trials on animals and cell cultures at the Department of Nuclear Medicine, University of Cologne, Germany, and to label them with 90Y. The vectors to transport radionuclides into tumour tissue for treatment were antibodies against lymphomas and neuroblastomas. Tumour pretargeting has shown clear advantages over the direct application of labelled antibodies with regard to tumour to background ratios. The pretargeting strategy would be first evaluated on cell cultures and the results then transferred to in vivo experiments on tumour bearing mice. Briefly, the first component of a three step pretargeting strategy would consist of the biotinylated antibody. This would include the protocol for determination of the number of biotin molecules per antibody. Using this technique, a stock of biotinylated antibody in lyophilized form can be built up, ready for further experiments. In the second step, commercially available avidin streptavidin would be used. The third and final step is the binding of radiolabelled (188Re, 90Y) biotin to the tumour cells through the avidin antibody bridge, after administration of a clearing agent. Initial evaluations of the potential radiopharmaceuticals have been carried out by in vitro experiments on cell lines expressing the corresponding antigen. The work done so far for the three step pretargeting method can be summarized as follows: —— Yttrium-90 labelling of biotin DOTA; —— Coupling of biotinylated rituximab to CD20 positive Raji cells; —— Successful labelling of cells conjugated with a complex of biotinylated antibody and avidin with 90Y DOTA biotin; —— First animal experiments with

  7. Advances on the treatment of solid tumor by 131I labeled mouse-human chimeric tumor necrosis therapy monoclonal antibody

    International Nuclear Information System (INIS)

    131I labeled mouse-human chimeric tumor necrosis therapy monoclonal antibody (131I-chTNT) is a kind of new drug targeting at degenerated or necrotic nuclei in the tumor necrosis zone,and may be applicable to the majority of human solid tumors, such as lung cancer, liver cancer,colon carcinoma and glioma, while conventional tumor cell monoclonal antibody can target only tumor cell surface antigen. Enhanced effects can be achieved by 131I-chTNT in combination with other therapies, such as radiotherapy,chemotherapy or radiofrequency ablation, which may increase tumor necrosis region and expose more combinative targets. (authors)

  8. Evaluation of 68Ga-Labeled MG7 Antibody: A Targeted Probe for PET/CT Imaging of Gastric Cancer

    OpenAIRE

    Bing Xu; Xiaowei Li; Jipeng Yin; Cong Liang; Lijuan Liu; Zhaoyan Qiu; Liping Yao; Yongzhan Nie; Jing Wang; Kaichun Wu

    2015-01-01

    MG7-Ag, a specific gastric cancer-associated antigen, can be used to non-invasively monitor gastric cancer by molecular imaging with positron emission tomography/computed tomography (PET/CT). In this study, we prepared and evaluated a 68Ga-labeled MG7 antibody as a molecular probe for nanoPET/CT imaging of gastric cancer in a BGC-823 tumor xenografted mouse model. Macrocyclic chelator 1,4,7-triazacyclononane-N,N0,N00-triacetic acid (NOTA)-conjugated MG7 antibody was synthesized and radiolabel...

  9. SIB-DOTA: A trifunctional prosthetic group potentially amenable for multi-modal labeling that enhances tumor uptake of internalizing monoclonal antibodies

    OpenAIRE

    Vaidyanathan, G.; White, B. J.; Affleck, D.J.; Zhao, X. G.; Welsh, P. C.; McDougald, D; Choi, J.; Zalutsky, M. R.

    2012-01-01

    A major drawback of internalizing monoclonal antibodies (mAbs) radioiodinated with direct electrophilic approaches is that tumor retention of radioactivity is compromised by the rapid washout of iodo-tyrosine, the primary labeled catabolite for mAbs labeled via this strategy. In our continuing efforts to develop more versatile residualizing labels that could overcome this problem, we have designed SIB-DOTA, a prosthetic labeling template that combines the features of the prototypical, dehalog...

  10. Establishment of 131I, 99mTc Labeling Methods to In-house Anti-CEA Antibodies and Evaluation of the Immunological Characteristics

    International Nuclear Information System (INIS)

    Cancer cells have several tumor-associated antigens on the cell surfaces, and antibodies against these antigens have been developed by many investigators. Radiolabeled antibodies have been used as new methods to diagnose and treat malignant tumors. Especially anti-carcinoembryonic antigen (CEA) is the most popular antibody for these purposes. In this investigation, we tried to label 131I and 99mTc to anti-CEA monoclonal antibodies which were developed in the Seoul National University College of Medicine. We found CEA-79 and CEA-92 antibodies had the better immunological characteristics among 8 anti-CEA monoclonal antibodies. And radioiodination of CEA-79 could be performed by chloramine-T method, while radioiodination of CEA-92 by iodogen method. To label these antibodies with 99mTc, we used pretargeting transchelation as direct labeling method. At first, 99mTc was bound to glucaric acid, and monoclonal antibody was reduced by β-mercaptoethanol. When these were incubated together, 99mTc bound to glucarate was switched to monoclonal antibody because of higher affinity. We established conditions of several steps in this method. Anti-CEA monoclonal antibodies labeled with 131I and 99mTc are expected to be used valuably in the detection and treatment of malignant tumors.

  11. 99mTc direct labeling of anti-CEA monoclonal antibodies: Quality control and preclinical studies

    International Nuclear Information System (INIS)

    The anti-carcinoembryonic B2C114 monoclonal antibody was radiolabeled with 99mTc by a direct method and quality control tested in vitro by instant thin layer chromatography, gel column scanning and cellulose acetate electrophoresis and assessed in vivo for radioimmunodetection on a murine spontaneous mammary carcinoma. The optimal results of percent 99mTc bound to protein were obtained at a dithiothreitol: antibody molar ratio ranging from 800:1 to 1000:1 and at a methylene diphosphonate: stannous fluoride weight ratio of 4.3:1. Although cysteine removed up to 18% of the label during the first 4 h, the stability of the tracer appeared to be excellent in human serum at 37 deg. C and when challenged with DTPA. 99mTc-labeled B2C114 demonstrated good and specific in vivo tumor targeting

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

    International Nuclear Information System (INIS)

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

  13. Tetrafluorophenolate of HBED-CC: a versatile conjugation agent for {sup 68}Ga-labeled small recombinant antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Eder, Matthias; Waengler, Bjoern; Eisenhut, Michael [German Cancer Research Center, Radiopharmaceutical Chemistry, Heidelberg (Germany); Knackmuss, Stefan; LeGall, Fabrice; Little, Melvyn [Affimed Therapeutics, Heidelberg (Germany); Haberkorn, Uwe; Mier, Walter [University of Heidelberg, Department of Nuclear Medicine, Heidelberg (Germany)

    2008-10-15

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

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

    International Nuclear Information System (INIS)

    The success of 68Ga-labeled peptides for positron emission tomography of neuroendocrine tumors is mainly depending on the complex chemistry of this radioisotope. 1,4,7,10-Tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), the chelator of choice has however limitations if its application is expanded to heat-sensitive proteins. Recombinant antibodies like single chain Fv or diabodies belong to this class of proteins. They are suited to provide imaging contrast despite the short-lived 68Ga because of their rapid blood clearances and nanomolar affinities. The heterobifunctional agent N,N'-bis[2-hydroxy-5-(carboxyethyl)benzyl]ethylenediamine-N,N'-diacetic acid (HBED-CC) was chosen as an alternative ligand because this agent is complexing [68Ga]Ga3+ much faster than DOTA at ambient temperatures. A versatile technology for HBED-CC conjugation of proteins and 68Ga-labeling has been developed. This included HBED-CC-tetrafluorophenol (TFP) ester synthesis, coupling to the antibody at various pH and complexation reactions performed in 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) buffer under different conditions. The synthesis of the monoreactive 2,3,5,6-tetrafluorophenolate of HBED-CC at a carboxyl group not participating in complex formation used [Fe(HBED-CC)]- for ester formation. The removal of Fe3+ from purified (HBED-CC)TFP ester was achieved with RP18 cartridge technology. The conjugation chemistry was performed with mAb425 which binds to the epidermal growth factor receptor (EGFR). This protein was used for optimizing purposes only. The influence of complexation parameters like temperature, pH, reaction time, and HBED-CC/antibody ratio on the biological activity of this model antibody was investigated. Furthermore, the outcome of this labeling procedure on the biological activity of a recombinant diabody (50 kDa) was studied. It is known that small HBED-CC/antibody ratios are prerequisites for minimal interference of labels with antigen

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

    DEFF Research Database (Denmark)

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

    2004-01-01

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

  16. Specific fluorescein-labeled antibodies to bovine viral diarrhea virus prepared from sera of rabbits immunized with purified virus.

    OpenAIRE

    Hart, R. A.; Rhodes, M B

    1980-01-01

    Specific fluorescein-labeled antibody conjugates to three strains of bovine virus diarrhea virus were prepared from hyperimmune rabbit sera. Viruses used to hyperimmunize the rabbits were purified by four different procedures. Conjugates were comparable in quality and specificity to conjugates prepared from serum of a calf hyperimmunized to bovine virus diarrhea virus in our laboratory. The latter conjugate was tested by Biologics Laboratories, National Veterinary Services, U.S.D.A., Ames, Iowa.

  17. Combinations of nonlabeled, 125I-labeled, and anti-idiotypic antiplacental alkaline phosphatase monoclonal antibodies at experimental radioimmunotargeting

    International Nuclear Information System (INIS)

    Purpose: Placental alkaline phosphatase (PLAP) is a membrane-bound oncofetal antigen that can be used for radioimmunotargeting. Preinjection of nonlabeled monoclonal anti-PLAP antibody (H7) and postinjection of monoclonal anti-idiotypic anti-PLAP antibody (αH7) were used in order to improve the localization efficacy of 125I-labeled H7. Material and Methods: A human cervix adenocarcinoma cell line (HeLa Hep 2) was inoculated subcutaneously in 24 nude mice. Repeated quantitative radioimmunoscintigraphic recordings were performed on 27 occasions in each of the 24 mice during the observation period which lasted for nearly 3 months. The tumor and nontumor doses were calculated according to the Medical International Radiation Dose Committee formula on the basis of the scintigraphic data. Results: All tumors were clearly visualized as early as one day after injection of 125I-labeled H7. The remaining radioactivity was exclusively located in the tumors at days 30-81. As much as 12-16% of the injected dose/g accumulated in the tumors during the first 2 days after injection, and remained stable at this high level for approximately 10 days in all investigated groups. Radioactivity in the whole body was rapidly eliminated during the same time period. The highest tumor/nontumor dose ratio was obtained after a single injection of 125I-labeled H7. Conclusion: Neither a preinjection of nonlabeled H7 nor a postinjection of αH7 nor a combination of both strategies resulted in improved tumor/nontumor dose ratios compared to a single injection of labeled H7. The monoclonal antibody H7 has a rapid and high uptake, combined with a prolonged retention time in the tumors. The kinetic properties of H7 are different form antibodies targeting intracellular tumor antigens. (orig.)

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

    International Nuclear Information System (INIS)

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

  19. Site-specifically 89Zr-labeled monoclonal antibodies for ImmunoPET

    International Nuclear Information System (INIS)

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

  20. Technetium-99m antibodies labeled with MAG3 and SHNH: An in vitro and animal in vivo comparison

    International Nuclear Information System (INIS)

    The in vitro stability and animal pharmacokinetics of 99mTc bound to Sandoz and C110 IgG antibodies via a modified MAG3 has been compared with the hydrazino nicotinamide (SHNH) moiety as standard. For both antibodies, the stabilities of the label to challenge at up to 50:1 cysteine: IgG molar ratio were comparable, but at higher molar ratios, MAG3 showed greater instabilities. For the Sandoz antibody, size-exclusion HPLC analysis of 37 degree sign C serum incubates and plasma samples from injected mice showed no clearly distinguishable differences. In the C110 case, some increased high molecular weight radioactivity was apparent with MAG3. Biodistributions in normal mice showed significant differences only in liver (Sandoz) and liver, spleen, intestines, stomach, and blood (C110), with SHNH usually providing higher levels. Thus, for two different antibodies and under the conditions of this study, the MAG3 chelator provided a 99mTc label with properties similar to that of SHNH moiety

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-09-01

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

  2. Antibodies raised against tobacco aquaporins of the PIP2 class label viscin tissue of the explosive dwarf mistletoe fruit.

    Science.gov (United States)

    Ross Friedman, C M; Ross, B N; Martens, G D

    2010-01-01

    Dwarf mistletoes, genus Arceuthobium, are parasitic flowering plants and forest pests. In western North America, Arceuthobium americanum (lodgepole pine dwarf mistletoe) is principally found on Pinus contorta var. latifolia (lodgepole pine). Dwarf mistletoes disperse their seeds by an explosive process that involves the buildup of hydrostatic pressure within a mucilaginous fruit tissue called the 'viscin'. Living viscin tissue envelops the discharged seeds. This study examined the possibility that aquaporins, critical in plant water relations, might be found in the dwarf mistletoe fruit, specifically the viscin cells. An antibody raised against a tobacco plasma membrane intrinsic 2 (PIP2) aquaporin was used with a gold-labeled secondary antibody to probe dwarf mistletoe fruit at various developmental stages. Viscin cell plasma membranes were successfully labeled with the anti-tobacco probe, and the validity of the immunolabeling was supported by Western blot analysis, showing a strong signal at about 30 kDa, which is at the expected size of a PIP2. A definitive immunolabeling pattern, supported by quantification of gold signal per membrane length, was observed: viscin cells sampled early in development had abundant gold label at their plasma membranes (1.93 +/- 0.13 to 2.13 +/- 0.33 gold particles per microm membrane), while other areas of the cells had no discernible label. Viscin cells sampled near the time of explosive discharge had significantly less label at the plasma membrane (0.21 gold particles +/- 0.11 per microm membrane, P < 0.05), and label was seen at vesicular membranes. Aquaporins likely have a role in directing water to the viscin mucilage early in development, but are retrieved via endocytosis to prevent excess water loss from viscin cells when discharge is imminent. PMID:20653906

  3. Feasibility of iodine-125 labeled anti-human hemoglobin antibody in the detection of bleeding sites from the large bowel-A preliminary study

    International Nuclear Information System (INIS)

    A monoclonal anti-human hemoglobin antibody that cross-reacts with mouse hemoglobin was labeled with Iodine-125 through the Chloramine-T method. The labeled antibody was used in an attempt to recognize bleeding sites from the large bowel in a mouse model, through a non-invasive enema-like study. In vitro experiments after double column chromatography of the labeled antibody and 10% trichloroacetic acid conjugation revealed that about 80% of the radioactivity was incorporated into protein. Inhibition assay containing could (non-radiolabeled) antibody showed that Iodine-125 radiolabeled antibody preserved its immunoreactivity. Autoradiographs exquisitely demonstrated accumulation of isotope in the corresponding intestinal bleeding areas. These findings suggest that this method can be useful for scintigraphic localization of bleeding sites in the large bowel. (author)

  4. Cell Wall Growth and Modulation Dynamics in a Model Unicellular Green Alga—Penium margaritaceum: Live Cell Labeling with Monoclonal Antibodies

    OpenAIRE

    Domozych, David S; Hannah Brechka; Alicia Britton; Marc Toso

    2011-01-01

    Penium margaritaceum is a unicellular charophycean green alga that possesses cell wall polymers similar to those of land plants. Several wall macromolecules of this alga are recognized by monoclonal antibodies specific for wall polymer epitopes of land plants. Immunofluorescence protocols using these antibodies may be employed to label specific cell wall constituents of live cells. Fluorescent labeling persists for several days, and this attribute allows for tracing of wall epitopes in both l...

  5. Antibody

    Science.gov (United States)

    An antibody is a protein produced by the body's immune system when it detects harmful substances, called antigens. Examples ... microorganisms (bacteria, fungi, parasites, and viruses) and chemicals. Antibodies may be produced when the immune system mistakenly ...

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

    International Nuclear Information System (INIS)

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

  7. Tumor necrosis treatment of ME-180 human cervical carcinoma model with 131I-labeled TNT-1 monoclonal antibody

    International Nuclear Information System (INIS)

    In contrast to normal tissues, many malignant tumors contain a high proportion of dead and dying cells. The loss of membrane integrity that accompanies cellular degeneration permits macromolecules, including antibodies, to freely enter the cell cytoplasm. Based upon these observations, it was hypothesized that monoclonal antibodies to intracellular antigens, which are integral structural components and are retained by degenerating cells, may be used to target a wide range of human malignancies. Previous studies by our laboratory utilizing these principles have demonstrated the feasibility of imaging four different histological types of human cancer in a nude mouse model, using monoclonal antibodies directed against insoluble intranuclear antigens. The present study describes the application of this approach, designated tumor necrosis treatment, for the radioimmunotherapy of transplantable ME-180 human cervical carcinomas in the nude mouse. Groups of tumor-bearing nude mice received three weekly treatments of 150 or 300 microCi of 131I-labeled experimental (TNT-1) or control (Lym-1) monoclonal antibodies. Detailed biodistribution data, dosimetric evaluations, and therapeutic results are presented to demonstrate the effective and preferential targeting of 131I-labeled TNT-1 monoclonal antibody within the tumor. In the experimental groups, the dose delivered to the tumor was sufficient to induce clinical regressions in 88% of treated animals, without evidence of toxicity to normal tissues. Complete regressions were obtained in 25% of the mice treated with high dose TNT-1. Microscopic examination of the implantation sites of these mice demonstrated the presence of acute radiation damage and residual keratin-positive tumor cells showing marked evidence of degeneration

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

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

  10. Pharmacokinetics of the monoclonal antibody B72.3 and its fragments labeled with either 125I or 111In

    International Nuclear Information System (INIS)

    A comparison of the pharmacokinetics of intact B72.3 (a murine monoclonal antibody specific for human breast and colon carcinoma) with F(ab')2 and Fab fragments labeled with 111In and 125I was done in athymic mice bearing target (LS174T) and non-target (HCT-15) tumors. IgG B72.3 labeled with either isotype imaged LS174T. Biodistributions of both labels were similar in all organs except liver. F(ab')2 also imaged the LS174T tumor, while Fab bearing either isotype did not. The blood clearance was Fab greater than F(ab')2 greater than immunoglobulin G B72.3 for both isotopes. 111In-labeled fragments yielded large accumulations in the kidneys which persisted for 2 days. The different patterns of biodistribution for the various forms of B72.3 labeled with the two isotopes suggest that the most desirable combination of fragment and isotope will depend on the intended use

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

    International Nuclear Information System (INIS)

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1991-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-03-18

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

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

    International Nuclear Information System (INIS)

    In the acute myocardium infarction, the myocytes cell membrane loses its integrity, allowing the influx of extracellular macromolecules such as circulating antibody into the damaged cell. The use of the specific antibodies against cardiac myosin labeled with 99mTc allows to determine the localization and extension of myocardial infarction. The purpose of this work was to study the viability of labeling of the antimyosin monoclonal antibody and its fragment F(ab')2 with 99mTc. Because of the high cost of antimyosin antibody, others antibodies were used to optimize the methodology and the best condition was used for antimyosin antibody. The intact antibody was cleaved by pepsin to produce F(ab')2 fragment. The F(ab')2 and the intact antibody were reduced by treatment with Dithiothreitol (DTT) and 2-Mercaptoethanol (2-ME) and labeled with 99mTc by direct method. Different concentrations of reductant, mixing conditions and incubation times were studied. In the standard condition, incubation at molar ratio 1:1000 (antibody:reducing agent) at room temperature for 30 minutes with continuous rotation (850 rpm), 13.28 - SH groups were formed per molecule. It was studied the influence of p H, of the concentration of stannous chloride (Sn2+) and incubation time in the labeling condition. The better radiochemical yield (90.06 +- 1.53%) was obtained using 2.5 μg of Sn2+ in p H 4.5 for 60 minutes. The labeling of the fragment F(ab')2 did not present satisfactory results because of the low yield of the digestion. After purification by PD-10, the biodistribution study was performed and showed that the intact antimyosin antibody labeled with 99mTc presented fast kinetic compatible with the biodistribution of an intact antibody labeled with 99mTc. Scintigraphy image of the animal with myocardial infarction was obtained and compared with the image of a normal animal. The studies allow to conclude that the use of fragment F(ab')2 are not viable, but the use of the labeled antimyosin

  15. Bismuth-212-labeled anti-Tac monoclonal antibody: alpha-particle-emitting radionuclides as modalities for radioimmunotherapy

    International Nuclear Information System (INIS)

    Anti-Tac, a monoclonal antibody directed to the human interleukin 2 (IL-2) receptor, has been successfully conjugated to the alpha-particle-emitting radionuclide bismuth-212 by use of a bifunctional ligand, the isobutylcarboxycarbonic anhydride of diethylenetriaminepentaacetic acid. The physical properties of 212Bi are appropriate for radioimmunotherapy in that it has a short half-life, deposits its high energy over a short distance, and can be obtained in large quantities from a radium generator. Antibody specific activities of 1-40 microCi/microgram (1 Ci = 37 GBq) were achieved. Specificity of the 212Bi-labeled anti-Tac was demonstrated for the IL-2 receptor-positive adult T-cell leukemia line HUT-102B2 by protein synthesis inhibition and clonogenic assays. Activity levels of 0.5 microCi or the equivalent of 12 rad/ml of alpha radiation targeted by anti-Tac eliminated greater than 98% the proliferative capabilities of HUT-102B2 cells with more modest effects on IL-2 receptor-negative cell lines. Specific cytotoxicity was blocked by excess unlabeled anti-Tac but not by human IgG. In addition, an irrelevant control monoclonal antibody of the same isotype labeled with 212Bi was unable to target alpha radiation to cell lines. Therefore, 212Bi-labeled anti-Tac is a potentially effective and specific immunocytotoxic reagent for the elimination of IL-2 receptor-positive cells. These experiments thus provide the scientific basis for use of alpha-particle-emitting radionuclides in immunotherapy

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

    International Nuclear Information System (INIS)

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

  17. Radioimmunoscintigraphy of human gastric carcinoma xenografts with 131I-labeled antigastric carcinoma monoclonal antibody, GL013

    International Nuclear Information System (INIS)

    Monoclonal antibody GL013 with specific binding reactivity in vitro to human tumors of the gastrointestinal tract was radioiodinated and injected intraperitoneally into nude mice bearing human gastric carcinoma xenografts SY86B (moderately differentiated glandular adenocarcinoma) and SY86D (signet ring cell carcinoma). Wholebody scintigraphy demonstrated tumor localization with 131I-labeled MAb GL013, but not with 131I-labeled normal mice immunoglobulin. Best tumor contrast was obtained between days 3 and 7 after injection. In confirmation of imaging results, 131I-GL013 preferentially localized in tumor tissue compared with normal tissue and 131I-GL013 gave higher tumor uptake ratio than did control 131I-NMIgG (at day 9 after injection), as determined by tissue counting of radioactivity. These results demonstrate that MAb GL013 does localize to the xenografts SY86D and SY86D and suggest the possible clinical application of MAb GL013 in radioimmunolocalization

  18. Analysis of the radiochemical purity of DTPA-coupled anti-CEA monoclonal antibody labelled with samarium-153

    International Nuclear Information System (INIS)

    Objective: To establish a paper chromatography method for analyzing radiochemical purity of cyclic DTPA anhydride coupled anti-CEA monoclonal antibody (McAb) labelled with 153Sm. Methods: The separation efficacy of free 153Sm3+ and 153Sm-CEA McAb was determined with a variety of paper chromatograph systems. The optimal separation conditions were studied, and the result determined with this paper chromatography compared with that of Sephadex G-50 chromatograph. Results: The optimal separation condition of the paper chromatograph system was as follows: Tributyl phosphate: 2-butanone: ethyl acetate (V/V/V = 4/10/3) as solvent and No. 1 Xinhua filter paper immerged with 30% ammonium nitrate for 30 min. and then dried as carrier. The percentage of labelling field determined with this paper chromatography was consistent with that of Sephadex G-50 chromatograph. Conclusion: It is showed this method proves to be simple, convenient and can be rapidly performed

  19. Positron Emission Tomography and Optical Imaging of Tumor CD105 Expression with a Dual-Labeled Monoclonal Antibody

    OpenAIRE

    Zhang, Yin; Hong, Hao; Engle, Jonathan W.; Yang, Yunan; Theuer, Charles P.; Barnhart, Todd E.; Cai, Weibo

    2012-01-01

    CD105 (endoglin) is an independent prognostic marker for poor prognosis in > 10 solid tumor types, including breast cancer. The goal of this study was to develop a CD105-specific agent for both positron emission tomography (PET) and near-infrared fluorescence (NIRF) imaging, which can have potential clinical applications in diagnosis and imaged-guided surgery of breast cancer. TRC105, a chimeric anti-CD105 monoclonal antibody, was labeled with both a NIRF dye (i.e. 800CW) and 64Cu to yield 64...

  20. Immunoradiometric assay of human proinsulin and partially processed proinsulin with use of monoclonal antibody and streptavidin-biotin labeling.

    OpenAIRE

    Kim, J Q; Cho, H. I.; Kim, S. I.; Lee, H. K.; Hales, C. N.

    1989-01-01

    The sensitive and specific immunoradiometric assay is described for human proinsulin and its intermediate peptides (65-66 split and 32-33 split proinsulin). We developed a monoclonal antibody-based two-site immunoradiometric assay with use of streptavidin-biotin labeling. The detection limits of the assays lie in the range of 0.5-2.0 pM. In the proinsulin assay proinsulin cross-reacted 66% with 65-66 split proinsulin but not with insulin or 32-33 split proinsulin. In the assay of 65-66 split ...

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

    Directory of Open Access Journals (Sweden)

    Minh-Chau Pham

    2013-01-01

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

  2. A Novel PET Imaging Using 64Cu-Labeled Monoclonal Antibody against Mesothelin Commonly Expressed on Cancer Cells

    Directory of Open Access Journals (Sweden)

    Kazuko Kobayashi

    2015-01-01

    Full Text Available Mesothelin (MSLN is a 40-kDa cell differentiation-associated glycoprotein appearing with carcinogenesis and is highly expressed in many human cancers, including the majority of pancreatic adenocarcinomas, ovarian cancers, and mesotheliomas, while its expression in normal tissue is limited to mesothelial cells lining the pleura, pericardium, and peritoneum. Clone 11-25 is a murine hybridoma secreting monoclonal antibody (mAb against human MSLN. In this study, we applied the 11-25 mAb to in vivo imaging to detect MSLN-expressing tumors. In in vitro and ex vivo immunochemical studies, we demonstrated specificity of 11-25 mAb to membranous MSLN expressed on several pancreatic cancer cells. We showed the accumulation of Alexa Fluor 750-labeled 11-25 mAb in MSLN-expressing tumor xenografts in athymic nude mice. Then, 11-25 mAb was labeled with 64Cu via a chelating agent DOTA and was used in both in vitro cell binding assay and in vivo positron emission tomography (PET imaging in the tumor-bearing mice. We confirmed that 64Cu-labeled 11-25 mAb highly accumulated in MSLN-expressing tumors as compared to MSLN-negative ones. The 64Cu-labeled 11-25 mAb is potentially useful as a PET probe capable of being used for wide range of tumors, rather than 18F-FDG that occasionally provides nonspecific accumulation into the inflammatory lesions.

  3. Radioimmunotherapy of fungal infection with 213-Bi- and 188-Re-labeled antibody

    International Nuclear Information System (INIS)

    Aim: Radioimmunotherapy (RIT) is a therapeutic modality that utilizes monoclonal antibodies (mAb) radiolabeled with therapeutic radioisotopes to selectively deliver lethal doses of radiation to cells. We hypothesized that 18B7 mAb (murine IgG1), specific for Cryptoccocus neoformans (CN) polysaccharide capsule, may be used to deliver fungicidal doses of radioisotopes to the sites of CN infection in vitro and in vivo. Materials and Methods: 18B7 mAb was radiolabeled with either the beta-emitter 188-Rhenium (188Re) or with the alpha-emitter 213-Bismuth (213Bi). The biodistribution of radiolabeled 18B7 was measured in BALB/c mice with and without intratracheal CN infection. For in vitro killing assays 105 CN cells/well were treated with 0-3.2 μCi 213Bi-18B7 (3 h incubation), 32 μCi 188Re-18B7 (48 h incubation) or with radiolabeled IgG1 MOPC21 as a control and minimal inhibitory concentrations (MIC) were determined. To compare the activity of radiolabeled mAb's against CN infection with an established antifungal drug, we evaluated the susceptibility of CN strain to Amphoterecin B. In vivo therapy of CN was conducted in groups of 10 A/JCr mice infected intravenously with 105 CN cells 24 h prior to treatment with 50-200 μCi 213Bi- or 188Re-18B7, 213Bi- or 188Re-MOPC21, unlabeled 18B7 or saline. Student's t test for unpaired data was used to analyze in vitro data, and log-rank test - for animal survival data. Results: MAb 18B7 preserved its immunoreactivity post-labeling and delivered 10% ID/g to the lungs of the CN-infected BALB/c mice in 24 h after injection. Two-log reduction in colony forming units (CFU) was achieved in treatment of CN with 213Bi-18B7 and 188Re-18B7, which compared favorably with Amphoterecin B. MIC's were determined to be 0.4 μCi/1.5 mg and 4 μCi/1.25 mg mAb for 213Bi-18B7 and 188Re-18B7, respectively. The fungicidal activity of irrelevant mAb 213Bi-or 188Re-MOPC21 was negligible (P213Bi-18B7 and of 100 μCi 188Re-18B7 significantly (P<0

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

    Directory of Open Access Journals (Sweden)

    Lei Zheng

    2012-12-01

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

  5. Biodistribution and radioimmunoimage of iodine-125 labeled anti-human ADAM15 polyclonal antibody in nude mice bearing human gastric carcinoma xenografts

    International Nuclear Information System (INIS)

    Objective: To investigate the biodistribution of Iodine-125 labeled anti-human ADAM15 polyclonal antibody in nude mice bearing human gastric carcinoma xenografts. Methods: The anti-human ADAM15 polyclonal antibody was labeled with I-125 using Chloramine-T method. The labeling efficiency and radiochemical purity of 125I-anti-ADAM15 antibody were measured. The SPECT planar imaging of nude mice bearing gastric carcinoma xenografts were performed at 1, 4, 8, 24, and 48 h post-injection and the biodistribution of 125I-anti-ADAM15 antibody was measured at 48 h after injection. Results: The labeling efficiency of 125I-anti-ADAM15 antibody was (75.16±9.43)% and its radiochemical purity was (99.44±0.21)% . Tumors could be cleanly visualized in SPECT planar images, and the radioactivity ratio of tumor to non-tumor tissue was 3.84±0.43 at 48 h post-injection. Conclusion: 125I-anti-ADAM15 antibody can target the gastric carcinoma in vivo, and provide good radioimmunoimages. (authors)

  6. Fluorescence aggregation assay for the protein biomarker mucin 1 using carbon dot-labeled antibodies and aptamers

    International Nuclear Information System (INIS)

    We have developed a sensitive fluorescence assay for the protein biomarker mucin 1 (MUC1). It is based on the aggregation of functionalized carbon dots (CDs) in the presence of MUC1. The CDs with a size of ∼2 nm display strong blue-green intrinsic fluorescence. Antibodies against MUC1 and the MUC1 aptamer were covalently conjugated to the CDs, and the immunoreaction between CD-labeled antibody to MUC1, and of the CD-labeled aptamer to MUC1 resulted in the formation of a sandwich structure that is accompanied by aggregation of CDs and quenching of fluorescence. The change in fluorescence is linearly related to the MUC1 concentration in the 5 to 100 nM range, with a detection limit at 2 nM. The assay was applied to the determination of MUC1 in (spiked) real serum samples, and good recoveries (ranging from 94.2 to 98.1 %) were obtained. This assay is cost-effective and convenient. It has a wide scope in that it, conceivably, can be extended to assays for other proteins and biomarkers of clinical interest. (author)

  7. In Vivo Molecular Imaging to Diagnose and Subtype Tumors through Receptor-Targeted Optically Labeled Monoclonal Antibodies

    Directory of Open Access Journals (Sweden)

    Yoshinori Koyama

    2007-12-01

    Full Text Available Molecular imaging of cell surface receptors can potentially diagnose tumors based on their distinct expression profiles. Using multifilter spectrally resolved optical imaging with three fluorescently labeled antibodies, we simultaneously imaged three different cell surface receptors to distinguish tumor types noninvasively. We selected tumors overexpressing different subtypes of EGFR receptor: HER-1 (A431 and HER-2 (NIH3T3/HER2+, or interleukin-2 receptor α-subunit receptor (IL-2Rα; SP2/Tac. After tumor establishment, a cocktail of three fluorescently labeled monoclonal antibodies was injected: cetuximab-Cy5 (targeting HER-1, trastuzumab-Cy7 (HER-2, daclizumab-AIexaFluor700 (IL-2Ra. Optical fluorescence imaging was performed after 24 hours with both a red filter set and three successive filter sets (yellow, red, deep red. Spectrally resolved imaging of 10 mice clearly distinguished A431, NIH3T3/HER2+, SP2-Tac tumors based on their distinct optical spectra. Three-filter sets significantly increased the signal-to-background ratio compared to a single-filter set by reducing the background signal, thus significantly improving the differentiation of each of the receptors targeted (P < .022. In conclusion, following multifilter spectrally resolved imaging, different tumor types can be simultaneously distinguished and diagnosed in vivo. Multiple filter sets increase the signal-to-noise ratio by substantially reducing the background signal, may allow more optical dyes to be resolved within the narrow limits of the near-infrared spectrum.

  8. Imaging cancer using PET - the effect of the bifunctional chelator on the biodistribution of a 64Cu-labeled antibody

    International Nuclear Information System (INIS)

    Introduction: Use of copper radioisotopes in antibody radiolabeling is challenged by reported loss of the radionuclide from the bifunctional chelator used to label the protein. The objective of this study was to investigate the relationship between the thermodynamic stability of the 64Cu-complexes of five commonly used bifunctional chelators (BFCs) and the biodistribution of an antibody labeled with 64Cu using these chelators in tumor-bearing mice. Methods: The chelators [S-2-(aminobenzyl)1,4,7-triazacyclononane-1,4,7-triacetic acid (p-NH2-Bn-NOTA): 6-[p-(bromoacetamido)benzyl]-1, 4, 8, 11-tetraazacyclotetradecane-N, N', N'', N'''-tetraacetic acid (BAT-6): S-2-(4-aminobenzyl)-1,4,7,10-tetraazacyclododocane tetraacetic acid (p-NH2-Bn-DOTA): 1,4,7,10-tetraazacyclododocane-N, N', N', N''-tetraacetic acid (DOTA): and 1-N-(4-aminobenzyl)-3,6,10,13,16,19-hexaazabicyclo[6.6.6]eicosane-1, 8-diamine (SarAr)] were conjugated to the anti-GD2 antibody ch14.18, and the modified antibody was labeled with 64Cu and injected into mice bearing subcutaneous human melanoma tumors (M21) (n = 3-5 for each study). Biodistribution data were obtained from positron emission tomography images acquired at 1, 24 and 48 hours post-injection, and at 48 hours post-injection a full ex vivo biodistribution study was carried out. Results: The biodistribution, including tumor targeting, was similar for all the radioimmunoconjugates. At 48 h post-injection, the only statistically significant differences in radionuclide uptake (p 64Cu]ch14.18-p-NH2-Bn-NOTA was 4.74 ± 0.77 per cent of the injected dose per gram of tissue (%ID/g), and for [64Cu]ch14.18-SarAr was 8.06 ± 0.77 %ID/g. Differences in tumor targeting correlated with variations in tumor size rather than which BFC was used. Conclusions: The results of this study indicate that differences in the thermodynamic stability of these chelator-Cu(II) complexes were not associated with significant differences in uptake of the tracer by the tumor

  9. Positron emission tomography and optical imaging of tumor CD105 expression with a dual-labeled monoclonal antibody.

    Science.gov (United States)

    Zhang, Yin; Hong, Hao; Engle, Jonathan W; Yang, Yunan; Theuer, Charles P; Barnhart, Todd E; Cai, Weibo

    2012-03-01

    CD105 (endoglin) is an independent prognostic marker for poor prognosis in >10 solid tumor types, including breast cancer. The goal of this study was to develop a CD105-specific agent for both positron emission tomography (PET) and near-infrared fluorescence (NIRF) imaging, which can have potential clinical applications in diagnosis and imaged-guided surgery of breast cancer. TRC105, a chimeric anti-CD105 monoclonal antibody, was labeled with both a NIRF dye (i.e., 800CW) and (64)Cu to yield (64)Cu-NOTA-TRC105-800CW. Flow cytometry analysis revealed no difference in CD105 binding affinity/specificity between TRC105 and NOTA-TRC105-800CW. Serial PET imaging revealed that the 4T1 murine breast tumor uptake of (64)Cu-NOTA-TRC105-800CW was 5.2 ± 2.7, 11.0 ± 1.4, and 13.0 ± 0.4% ID/g at 4, 24, and 48 h postinjection respectively. Tumor uptake as measured by ex vivo NIRF imaging exhibited a good linear correlation with the % ID/g values obtained from PET (R = 0.74). Biodistribution data were consistent with the PET/NIRF findings. Blocking experiments, control studies with dual-labeled cetuximab (an isotype-matched control antibody), and histology confirmed the CD105 specificity of (64)Cu-NOTA-TRC105-800CW. Successful PET/NIRF imaging of CD105 expression warrants further investigation and clinical translation of dual-labeled TRC105-based imaging agents. PMID:22292418

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

    International Nuclear Information System (INIS)

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

  11. An accurate radioimmunoassay of human growth hormone with separation on polyacrylamide gel electrophoresis of free antigen, antigen-antibody complex and damaged labelled antigen. Further study of damaged labelled antigen to obtain long-lasting labelled products

    International Nuclear Information System (INIS)

    The purpose of this work was to obtain a radioimmunoassay that would be sufficiently accurate and precise to provide a suitable means of determining human growth hormone (hGH) in both extracts and physiological fluids for specific research purposes rather than for routine clinical assays where the labelled products could be used as long as possible. The only technique found that could satisfy these requirements was polyacrylamide gel electrophoresis (PAGE), though in some respects it is more laborious than other techniques. By introducing some modifications to the original method of Davis it was possible, with 11-cm tubes, to separate the free, the antibody-bound, and the damaged labelled antigen on the same gel. The method, being able to detect separately and independently these three components and to give a better control of the analytically dangerous ''damaged'' antigens, furnished accurate and reproducible curves. An example of a determination is the one on KABI-Crescormon which compares the results obtained with the present technique with those presented by another laboratory. Thanks to this method, the labelled antigen could be used for up to one month, after which re-purification on Sephadex enabled the same labelled product to be used profitably for two more months. Parallel to this work, a study has been performed on the various components originating in this so-called process of ''damaging'', and particular importance has been given to a more precise knowledge of the amount of antigen, in terms of mass, present in an assay. (author)

  12. Preclinical evaluation of copper-67 labelled anti-MUC1 mucin antibody C595 for therapeutic use in bladder cancer

    International Nuclear Information System (INIS)

    Transitional cell carcinoma of the bladder is the fifth commonest cause of death from cancer in men in the United Kingdom. Most patients present early with superficial disease, though with current treatment up to 20% progress to invasive disease, which has a poor prognosis. Better local treatments are required to limit this tumour progression. The ease of access to the bladder via a catheter provides the ideal opportunity for antibody (Ab) targeted therapy. We have previously shown that indium-111 labelled anti-MUC1 mucin Ab C595 selectively localises to bladder tumours after intravesical administration. We have selected copper-67 as an alternative radiolabel with suitable physical characteristics for radioimmunotherapy. This communication demonstrates that C595 can be reproducibly labelled with 67Cu and that the radioimmunoconjugate is both stable and maintains high immunoreactivity. Pilot studies on cystectomy specimens in a novel ex vivo system and in one patient confirmed the ability of this conjugate to localise to tumour after intravesical administration. On the basis of these studies we are now in a position to study the intravesical administration of 67Cu-labelled C595 in patients with bladder cancer with a view to a therapeutic trial. (orig.). With 4 figs., 1 tab

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

    International Nuclear Information System (INIS)

    99Tcm-labelled monoclonal antibodies (MAbs) and human immunoglobulins (hIgG) have recently emerged as a new class of site specific radiopharmaceuticals. The role of 99Tcm-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 99Tcm-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

  14. Imaging of pharyngeal and laryngeal carcinomas with indium-111-labeled monoclonal anti-CEA antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Kairemo, K.J.; Hopsu, E.V. (Helsinki Univ. Central Hospital (Finland))

    1990-10-01

    Localization of primary tumors, metastases, or recurrences in 13 consecutive patients with histological verification of squamous cell or adenocarcinoma was made with radioimmunodetection using monoclonal radiolabeled anti-CEA antibody. All surgical specimens stained immunohistochemically, except one, were positive for CEA. Of the known 19 tumor sites 17 were visualized in antibody scans. There were two positive findings that did not prove to be positive during 12 month follow-up. The scintigram findings did not correlate with CEA serum concentrations that, with one exception, were normal in all patients.

  15. Labelled monoclonal antibodies used for the detection of inflammatory processes and bone marrow metastases

    International Nuclear Information System (INIS)

    This review gives a short history of the developments of immunoscintigraphy using radiolabelled monoclonal antibodies and will look at some clinical indications studied in close cooperation with international groups. Examples are presented of infected orthopaedic prostheses and the diagnosis of osteomyelitis in diabetic foot in which the method is considered diagnostically helpful. Furthermore, the accuracy of the bone marrow immunoscintigraphy is discussed in evaluating results of a multi-centre study, clearly demonstrating its diagnostic superiority over bone scanning in metastatic cancer. It is concluded that the future diagnostic trend is going towards more specific agents (antibodies, peptides) and a speedier availability of the diagnostic results in cases of supposed infection. (author)

  16. Imaging of pharyngeal and laryngeal carcinomas with indium-111-labeled monoclonal anti-CEA antibodies

    International Nuclear Information System (INIS)

    Localization of primary tumors, metastases, or recurrences in 13 consecutive patients with histological verification of squamous cell or adenocarcinoma was made with radioimmunodetection using monoclonal radiolabeled anti-CEA antibody. All surgical specimens stained immunohistochemically, except one, were positive for CEA. Of the known 19 tumor sites 17 were visualized in antibody scans. There were two positive findings that did not prove to be positive during 12 month follow-up. The scintigram findings did not correlate with CEA serum concentrations that, with one exception, were normal in all patients

  17. Targeting of renal carcinoma with 67/64Cu-labeled anti-L1-CAM antibody chCE7: selection of copper ligands and PET imaging

    International Nuclear Information System (INIS)

    In order to optimize radiocopper labeling of anti-L1-CAM antibody chCE7, five bifunctional copper chelators were synthesized and characterized (CPTA-N-hydoxysuccinimide, DO3A-L-p-isothiocyanato-phenylalanine, DOTA-PA-L-p-isocyanato-phenylalanine, DOTA-glycyl-L-p-isocyanato-phenylalanine and DOTA-triglycyl-L-p-isocyanato-phenylalanine). Substitution with more than 11 chelators per antibody molecule was found to influence immunoreactivity and biodistributions of 67Cu-MAb chCE7 significantly. CPTA-labeled antibody achieved the best tumor to normal tissue ratios when biodistributions of the different 67Cu-chCE7 conjugates were assessed in tumor-bearing mice. High resolution PET imaging with 64Cu-CPTA-labeled MAb chCE7 showed uptake in lymph nodes and heterogeneous distribution in tumor xenografts

  18. Localization of 131I-labelled monoclonal antibody ERIC1 in a subcutaneous xenograft model of neuroblastoma in SCID mice

    International Nuclear Information System (INIS)

    Our purpose was to evaluate a novel strategy of immunolocalization of human neuroblastoma by targeting the neural cell adhesion molecule (NCAM), which is over-expressed on neuroblastoma. Neuroblastoma is the most frequent solid extracranial childhood tumour and also the most common neoplasm in the first year of life. The most frequent metastatic sites are bone, bone marrow and liver. The neural cell adhesion molecule (NCAM) is constitutively expressed on nearly 100% of all neuroblastomas. NCAM has been successfully used as a target for immunotoxines and bi-specific antibodies in multiple myeloma, small cell lung cancer, glioma or neuroblastoma, in vitro and in vivo. NCAM expression was quantified on established neuroblastoma cells by real time PCR and NCAM expression on the cell surface shown by flow cytometry. A SCID mouse model using IMR5-75 neuroblastoma cells to induce subcutaneous tumour growth was established. 131I was used to label monoclonal NCAM specific ERIC1 antibodies generating the 131I-ERIC1 antibody, which shows a high affinity to NCAM also after labelling (KD= 9 x 10-8). Groups of five to six mice received intravenous injections of 3-9 MBq of 131I-ERIC1 on day 0 into the tail vein. At time points 2.5 h, 24 h, 48 h, 72 h and 96 h post injection mice were sacrificed by cervical dislocation. Blood, liver, spleen, kidneys, muscle, femur, thyroid, intestines, lung, tumour and urine were removed and weighed. Organ-specific radioactivity was measured in a well-counter as well as that of the tail and remnant cadavers. Data were calculated as dose per gram of tissue (%ID/g) and tumour to non-tumour ratios (T/NT ratio). For blocking experiments mice were pre-injected with 140μg of unlabelled ERIC1 into the tail vein 24 h prior 131I-ERIC1 application. Mice from these blocking experiments were measured after 72 h. Measurement of organ-specific radioactivity showed low organ-specific uptake (5.33 %ID/g after 72 h), which continuously decreased over the 96 hour

  19. Demonstration of dnp groups on the draining lymph node cells of guinea pigs following skin painting with DNCB by peroxidase labelled antibody method.

    Directory of Open Access Journals (Sweden)

    Tada,Hiroshi

    1981-06-01

    Full Text Available The distribution of 2,4-dinitrophenyl (DNP groups in the draining lymph nodes of guinea pigs 12 h after painting the skin with 2,4-dinitrochlorobenzene (DNCB was examined by a peroxidase labelled antibody method using antibody against DNP groups. DNP groups were detected on cells that were found mainly in the subcapsular sinus of the lymph nodes. Electron microscopic examination showed DNP groups distributed on the surface of lymphocytes. The significance of these findings is discussed.

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

    International Nuclear Information System (INIS)

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

  1. Surface Plasmon Resonance Label-Free Monitoring of Antibody Antigen Interactions in Real Time

    Science.gov (United States)

    Kausaite, Asta; van Dijk, Martijn; Castrop, Jan; Ramanaviciene, Almira; Baltrus, John P.; Acaite, Juzefa; Ramanavicius, Arunas

    2007-01-01

    Detection of biologically active compounds is one of the most important topics in molecular biology and biochemistry. One of the most promising detection methods is based on the application of surface plasmon resonance for label-free detection of biologically active compounds. This method allows one to monitor binding events in real time without…

  2. PET Imaging of CD105/Endoglin Expression with a 61/64Cu-Labeled Fab Antibody Fragment

    Science.gov (United States)

    Zhang, Yin; Hong, Hao; Orbay, Hakan; Valdovinos, Hector F.; Nayak, Tapas R.; Theuer, Charles P.; Barnhart, Todd E.; Cai, Weibo

    2013-01-01

    Purpose The goal of this study was to generate and characterize the Fab fragment of TRC105, a monoclonal antibody that binds with high affinity to human and murine CD105 (i.e. endoglin), and investigate its potential for positron emission tomography (PET) imaging of tumor angiogenesis in a small animal model after 61/64Cu-labeling. Methods TRC105-Fab was generated by enzymatic papain digestion. The integrity and CD105 binding affinity of TRC105-Fab was evaluated before NOTA (i.e., 1,4,7-triazacyclononane-1,4,7-triacetic acid) conjugation and 61/64Cu-labeling. Serial PET imaging and biodistribution studies were carried out in the syngeneic 4T1 murine breast cancer model to quantify tumor targeting efficacy and normal organ distribution of 61/64Cu-NOTA-TRC105-Fab. Blocking studies with unlabeled TRC105 were performed to confirm CD105 specificity of the tracer in vivo. Immunofluorescence staining was also conducted to correlate tracer uptake in the tumor and normal tissues with CD105 expression. Results TRC105-Fab was produced with high purity through papain digestion of TRC105, as confirmed by SDS-PAGE, HPLC analysis, and mass spectrometry. 61/64Cu-labeling of NOTA-TRC105-Fab was achieved with ~50% yield (specific activity: ~44 GBq/µmol). PET imaging revealed rapid uptake of 64Cu-NOTA-TRC105-Fab in the 4T1 tumor (3.6 ± 0.4, 4.2 ± 0.5, 4.9 ± 0.3, 4.4 ± 0.7, and 4.6 ± 0.8 %ID/g at 0.5, 2, 5, 16, and 24 h post-injection respectively; n = 4). Since tumor uptake peaked soon after tracer injection, 61Cu-labeled TRC105-Fab was also able to provide tumor contrast at 3 and 8 h post-injection. CD105 specificity of the tracer was confirmed with blocking studies and histological examination. Conclusion Herein we report PET imaging of CD105 expression with 61/64Cu-NOTA-TRC105-Fab, which exhibited prominent and target specific uptake in the 4T1 tumor. The use of a Fab fragment led to much faster tumor uptake (which peaked at a few hours after tracer injection) compared to

  3. Iodine 131 labeled GD2 monoclonal antibody in the diagnosis and therapy of human neuroblastoma

    International Nuclear Information System (INIS)

    High dose marrow ablative therapy followed by autologous bone marrow transplantation (ABMT) has prolonged survival in patients with neuroblastoma. Total body and focal irradiation play an integral role in the overall treatment of this disease. The biological basis for radiation is the radiosensitivity and the lack of sublethal repair in neuroblastoma cells. However, radiation therapy has not by itself been adequate because of the usual widespread nature of neuroblastoma and the inability to achieve selective tumor versus normal tissue delivery, especially at multiple tumor sites. Monoclonal antibodies are agents selected for their specificity for human tumors. In vivo they have the ability of targeting selectively to occult metastases. This paper discusses how the availability of radioisotopes and the development of conjugation chemistries have greatly expanded the potentials of these antibodies

  4. Comparative distribution study of /sup 111/In-labelled DTPA and TTHA monoclonal antibody conjugates in a choriocarcinoma xenograft model

    Energy Technology Data Exchange (ETDEWEB)

    Buckley, R.G.; Barnett, P.; Searle, F.; Pedley, R.; Boden, J.A.

    1986-11-01

    Conjugates of the chelating agents DTPA and TTHA with a monoclonal anti-HCG were prepared. The tissue distribution of the /sup 111/In-Labelled conjugates and also /sup 111/In-citrate was studied in mice bearing human choriocarcinoma xenografts. The antibody conjugates both gave high liver and spleen radionuclide accumulation. Elevated femur levels were observed for the TTHA conjugate and /sup 111/In-citrate. Generally the DTPA conjugate showed the highest tumor-tissue ratios, although its tumor/blood ratio was lower than the other two materials. The results infer that the DTPA conjugate has the greatest utility as an imaging agent but that it would require a background subtraction technique.

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

    Science.gov (United States)

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

    1995-12-01

    Radioimmunoscintigraphy (RIS) using human monoclonal antibodies offers the important clinical advantage of repeated imaging over murine monoclonal antibodies by eliminating the cross-species antibody response. This article reports a Phase I-II clinical trial with Tc-99m-labeled, totally human monoclonal antibody 88BV59H21-2 in patients with colorectal carcinoma. The study population consisted of 34 patients with colorectal cancer (20 men and 14 women; age range, 44-81 years). Patients were administered 5-10 mg antibody labeled with 21-41 mCi Tc-99m by the i.v. route and imaged at 3-10 and 16-24 h after infusion using planar and single-photon emission computed tomographic (CT) techniques. Pathological confirmation was obtained in 25 patients who underwent surgery. Human antihuman antibody (HAHA) titers were checked prior to and 1 and 3 months after the infusion. RIS with Tc-99m-labeled 88BV59H21-2 revealed a better detection rate in the abdomen-pelvis region compared with axial CT. The combined use of both modalities increased the sensitivity in both the liver and abdomen-pelvis regions. Ten patients developed mild adverse reactions (chills and fever). No HAHA response was detected in this series. Tc-99m-labeled human monoclonal antibody 88BV59H21-2 RIS shows promise as a useful diagnostic modality in patients with colorectal cancer. RIS alone or in combination with CT is more sensitive than CT in detecting tumor within the abdomen and pelvis. Repeated RIS studies may be possible, due to the lack of a HAHA response. PMID:7493345

  6. The labelling of antibody anti-PBP2a with 99mTc

    International Nuclear Information System (INIS)

    Staphylococcus aureus is a major cause of life-threatening infections such as bacteraemia and endocarditis. Unfortunately, many strains of this bacterial species have become resistant to certain antibiotics, including methicillin and amoxicillin. These strains are known as methicillin-resistant S. aureus (MRSA). The penicillin binding protein 2a (PBP2a) is the enzyme responsible for conferring resistance p-lactams antibiotics for MRSA, being one promising molecule for therapy with mAb. However, besides the therapy, the methods of diagnosis are also inefficient because the diagnosis currently takes several days to produce a reliable result. Taking into account, the objective of this research was radiolabeling one anti-PBP2a mAb developed by Bio-Manguinhos/FioCruz-RJ, utilizing 99mTc, for in situ diagnostic of the infectious caused by MRSA. First, anti-PBP2a mAb was reduced utilizing 2-mecaptoethanol (2-ME) for generate sulphydryl groups (-SH) and after to be labeled with 99mTc. In this work, were utilized two techniques of direct method: Method 1, using tartrate and gentisic acid reagents, acting like transchelant and stabilizer agents, respectively; and Method 2, using one commercial kit of MDP. Besides the radiolabeling, the mAb reduced and mAb labeled with 99mTc were submitted to immunoreactivity analysis, with SDS-PAGE non-reducing, Immunoblotting, ELISA and neutralization assay in vitro methods. The quantity produced of sulphydryl groups by mAb was satisfactory, approximately 5 per mAb, utilizing 6.500:1 of 2-ME:mAb molar ratio. The better labeling method was Method 2, with labeling yield of 73.5%, and showed a good stability after 2 hours (73.2%). The better formulation was: 0.5 mg of mAb anti- PBP2a, 10 μU of MDP kit, after resuspended with 5 mL of saline, and 75.48 MBq (2.04 mCi) of 99mTc, reacting by 15 minutes. The labeled mAb maintained the immunoreactivity, utilizing immunologic and in vitro experiments. (author)

  7. Detection of plasma α-granule membrane protein (GMP-140) using 125I labeled monoclonal antibodies and its clinic applications

    International Nuclear Information System (INIS)

    Radioimmunoassay with two monoclonal antibodies to different epitopes of granule membrane protein (GMP-140) was used to measure the plasma GMP-140 level in patients suffering from acute myocardial infarction (AMI) or cerebral thrombosis and in patients during cardiopulmonary bypass (CPB). Monoclonal antibody (McAb) SZ-51 was used as a solid phase and 125I-labeled McAb S12 as a fluid phase. The assay was so sensitive that it could detect as little as 1 μg/L of purified GMP-140. The intra- and inter-assay coefficients of variation were 4.2% and 7.1% respectively. The concentration of plasma GMP-140 was found to be 10 +- 4.5 μg/L in normal subjects (n = 20). Patients undergoing CPB (n = 10) and patients with AMI (n = 16) or with acute cerebral thrombosis (n = 22) were also studied. The results suggest that plasma GMP-140 can be reliable detected by radioimmunoassay with two McAbs and plasma GMP-140 may provide a useful marker for thrombotic diseases

  8. Immunoassay of 5-methyltetrahydrofolate: use of 125I-labeled protein A as the tracer molecule for specific antibody

    International Nuclear Information System (INIS)

    A sensitive and specific solid-phase radioimmunoassay for 5-methyltetrahydrofolate (5-MTHFA) has been developed. 125I-Labeled staphylococcal Protein A (125I-PA) was used as the tracer molecule for rabbit IgG antibodies bound to 5-MTHFA immobilized on polyacrylamide beads. The dose-dependent inhibition of antibody binding by fluid-phase drug was reflected in decreased binding of 125I-PA. This inhibition, determined in the presence of known amounts of 5-MTHFA, served as the basis for quantification of 5-MTHFA in test samples. An early bleeding was relatively specific; 4.5 ng 5-MTHFA inhibited immune binding by 50% compared to 7700 ng folinic acid or 1200 ng tetrahydrofolate. Other folic acid analogs, including methotrexate, failed to inhibit significantly. The assay using a later bleeding was more sensitive since 1.6 ng 5-MTHFA gave 50% inhibition (detection limit 0.2 ng), but folinic acid cross-reacted significantly. Absorption with immobilized folinic acid markedly enhanced the specificity of this antiserum and resulted in a 15 to 20% increase in maximum inhibition by 5-MTHFA. The assay could be carried out in the presence of 0.025 ml human serum or urine without affecting the standard curve, and was used to determine levels of 5-MTHFA in serum of drug-treated rabbits

  9. Radioimmunolocalization of human gastric carcinoma xenografts SY 86 B and SY 86 D with 131I-labeled monoclonal antibody

    International Nuclear Information System (INIS)

    The suitability of individual MAb for application in vivo should be carefully confirmed. The monoclonal antibody GL-013, with specific binding reactivity in vitro to human tumors of the gastrointenstinal tract, was radioiodinated and injected intraperitoneally into nude mice bearing human gastric carcinoma xenografts SY 86 B (moderately differentiated glandular adenocarcinoma) and SY 86 D (signet ring cell carcinoma). Whole body scintigraphy indicated tumor localization with 131I-labeled MAb GL-013, but not with 131I-labeled normal mice immunoglobulin. The best tumor contrast was obtained between days 3 and 7 after injection. As confirmation of the imaging results, 131I-GL-013 preferentially localized in tumor tissue compared with normal tissue and 131I-GL-013 gave a higher tumor uptake ratio than the control 131I-NMIgG (at day 9 after injection), as determined by tissue counting of radioactivity. These results demonstrate that MAb GL-013 localizes in xenografts SY 86 B and SY 86 D and the possible clinical application of MAb GL-013 to radioimmunolocalization. (author)

  10. Kinetics and dosimetry of iodine-131-labelled antibody fragments after local administration in patients with rectal cancer

    International Nuclear Information System (INIS)

    In 11 patients with rectal cancer, a mixture of F(ab')2 fragments of anti-carcinomembryonic antigen and anti-CA 19.9 labelled with a diagnostic dose of iodine-131 (3-10 MBq) was administered submucosally around the tumour. In this study, the local kinetics in and the dose to the rectal wall, the whole body kinetics and the effective dose equivalent are presented. Initially, about 50% of the plasma activity was due to free 131I. After 4 h, the plasma activity was almost completely protein bound (86%). Maximum plasma activity was observed after the 2nd day. In the first 24 h, 14% of the injected dose was excreted in the urine and within 4 days about half of the administered activity. The absorbed radiation dose to the rectal wall was estimated to be 0.2 Gy/MBq. The dose to the bone marrow was 0.2 mGy/MBq or 0.4 mGy/MBq, assuming a homogeneous tracer distribution or equal blood and bone marrow activity concentrations, respectively. The effective dose equivalent is 1.9 mSv/MBq. We conclude that the theoretical advantages of the local administration of 131I-labelled antibodies for diagnostic purposes in patients with rectal cancer are not limited by our dosimetric data. Nevertheless, we advocate the use of other radiolabels with more appropriate imaging qualities and probably a lower radiation burden. (orig./MG)

  11. Distribution and radioimmunoimaging of 131I labeled anti-NPC monoclonal antibody BAC5 in tumor bearing nude mice

    International Nuclear Information System (INIS)

    To provide an evidence for clinical applications, the distribution and radioimmunoimaging of 131I labeled anti nasopharyngeal carcinoma (NPC) monoclonal antibody BAC5 in tumor bearing nude mice were studied. McAb BAC5, against NPC, was labeled with 131I and injected into nude mice bearing NPC cell line CNE-2. The biodistribution of 131I-BAC5 and whole body ECT imaging were studied at various intervals after injection. The % ID/g were 6.38, 11.27 and 14.19 for tumor and 7.78, 3.48 and 2.59 for liver at 48, 96 and 144h postinjection respectively. The T/NT ratios were 0.82, 3.24 and 5.47 for liver at 48, 96 and 144h postinjection respectively. Tumor showed clearly at 3 days after injection. The quality of tumor images was relevant to the T/NT ratio. The results demonstrated that McAb BAC5 has specifically bind to NPC tissue and may also possess the capability of leading to human NPC

  12. Development of indirect competitive fluorescence immunoassay for 2,2',4,4'-tetrabromodiphenyl ether using DNA/dye conjugate as antibody multiple labels

    Science.gov (United States)

    An indirect competitive fluorescence immunoassay using DNA/dye conjugate as antibody multiple labels was developed on 96-well plates for the identification and quantification of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) in aqueous samples. A hapten, 2,4,2'-tribromodiphenyl ether-4’-aldehyde was sy...

  13. Substituent-specific antibody against glucuronoxylan reveals close association of glucuronic acid and acetyl substituents and distinct labeling patterns in tree species

    DEFF Research Database (Denmark)

    Koutaniemi, Sanna; Guillon, Fabienne; Tranquet, Olivier; Bouchet, Brigitte; Tuomainen, Päivi; Virkki, Liisa; Pedersen, Henriette Lodberg; Willats, William George Tycho; Saulnier, Luc; Tenkanen, Maija

    2012-01-01

    antibody binding. The treatment removed acetyl groups from xylan, indicating that the vicinity of glucuronic acid substituents is also acetylated. The novel labeling patterns observed in the xylem of tree species suggested that differences within the cell wall exist both in acetylation degree and in...

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

    International Nuclear Information System (INIS)

    An autoradiographic method for detecting soluble antigen (chicken serum albumin, CSA) and specific antibodies in the spleen of rabbits during a primary immune response is described. The method consists of incubating sections from the spleen with 125I-labelled IgG2 anti CSA (for demonstration of antigen) or with 125I-labelled antigen (for demonstration of specific antibodies). This treatment of histological sections combines the advantages and principles of the immunofluorescence technique with the possibility of evaluating the exact localization of the proteins by light microscopy in preparations stained with haematoxylin or methyl green-pyronin. The sensitivity of detection is very high: both antigen and antibodies could be demonstrated in the spleen follicles for as long as 42 days after the primary intravenous injection

  15. Radioimmunoimaging of ovarian cancer with 131I labelled CEA monoclonal antibody

    International Nuclear Information System (INIS)

    Objective: To investigate radioimmunoimaging with 131I labelled CEA McAb and its value in diagnosis and treatment of ovarian cancer. Methods: CEA McAb was labelled with 131I 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 131I-CEA McAb is valuable and helpful in early detection of ovarian cancer. It is also helpful for clinical staging, treatment programing and prognosticating

  16. Effect of chloramine-T labeling conditions on the stability of monoclonal antibodies and their fragments

    International Nuclear Information System (INIS)

    Rapid in vivo degradation of radioiodinated monoclonal antibodies (MAb) has been reported. Conditions for radioiodination have varied. The purposes of this study were to compare the stability of MAb and their fragments when iodinated with chloramine-T (CT) under different conditions, and to compare methods for quality assessment of the radioiodinated molecules. A B-cell lymphoma MAb (Lym-1, IgG2a) and its FAb fragment, and a mammary cancer MAb(B6.01, IgG1) and its F(Ab')/sub 2/ fragment were iodinated with I-125 at CT:AB and I:Ab ratios of 1:1 and 1:10. Molecular sieving (TSK-3000) high performance liquid chromatography (HPLC), cellulose acetate electrophoresis (CAE) at 11 and 45 minutes and solid phase immunoreactivity (IRA) were used to observe stability of the molecules when stored at 40C. Radiochemical yield was greater than 95% in all instances. Iodination at CT:Ab and I:Ab ratios of 1:1 induced progressive degradation in all species which was most marked for the fragments. Iodination at CT:Ab and I:Ab ratios of 1:10 resulted in no observable degradation over 21 days. There was no significant difference in degradation between the IgG2a and IgG1 antibody when iodinated under identical circumstances. HPLC, CAE for 11 minutes and IRA, but not CAE for 45 minutes, revealed comparable changes. The authors conclude that lesser amounts of chloramine-T can be used to iodinate MAb and their fragments without loss of radiochemical efficiency and with improved stability of the species. MAb fragments are more vulnerable to chloramine-T. These observations may explain, at least in part, rapid in vivo degradation of radioiodinated MAb

  17. Radiopharmaceutical management of 90Y/111In labeled antibodies. Shielding and quatification during preparation and administration

    International Nuclear Information System (INIS)

    The combined application of potent β-emitting isotopes for therapy with γ-emitting isotopes for scintigraphy requires a profound regimen concerning team member safety and radionuclide quantification. We have developed materials and methods for a proper and easy manipulation of 90Y during preparation and administration of 90Y/111In pharmaceuticals used for radioimmunotherapy. The efficacy of the shielding measures is documented. Protocols for the calibration of γ-dose calibrators with respect to 90Y are extended to the assessment of quench-corrected liquid scintillation counting of 90Y. The contribution of 90Y backscatter to 111In counting is quantified. Newly developed shielding equipment allows an adequate administration of relatively large volumes (100 ml) of 90Y/111In labeled pharmaceuticals to patients. The procedures described combine pharmaceutical (Good Manufacturing Practice) and radiation safety requirements with an accurate logging of relevant data. (author)

  18. Addendum to report of the research co-ordination meeting on labelling techniques of biomolecules for targeted radiotherapy. Country report: Hungary. Preparation, quality control and animal testing of 125I and 131I labelled monoclonal antibody for radiotherapy

    International Nuclear Information System (INIS)

    Radiolabelled monoclonal antibodies (MoAbs) against tumour-associated antigens have been used to detect tumour deposits. Since gamma camera imaging of patients injected with radiolabelled MoAbs has demonstrated, selective tumour uptake of MoAbs, antibody-directed radiotherapy has gained greater interest. Prior to employing antibodies for radioimmunotherapy, their tumour and normal tissue uptake and pharmacokinetics as well as therapeutic efficacy in the animal tumour model must be determined. The therapeutic radiopharmaceuticals consist of two components the radionuclide (beta, alpha, Anger and conversion electron emitters) and the biological carrier (from peptide- to antibody). In the first step of our research program anti CEA MoAb inj. labelled with iodine-125 and 131I isotopes were used to study therapeutic efficacy in nude mice bearing human gastric adenocarcinoma xenografts

  19. 90Nb: potential radionuclide for application in immuno-PET. Development of appropriate production strategy and first in vivo evaluation of 90Nb-labeled monoclonal antibody

    International Nuclear Information System (INIS)

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

  20. Comparison of 131I- and 90Y-labeled monoclonal antibody 17-1A for treatment of human colon cancer xenografts

    International Nuclear Information System (INIS)

    The choice of radionuclide remains an important question in clinical radioimmunotherapy. Therefore, a study was initiated, using an in vivo model system, to assess the relative merits of 131I- and 90Y-labeled 17-1A monoclonal antibody as therapeutic agents in the treatment of colon cancer. 131I- and 90Y-labeled 17-1A were assessed in animal therapy trials using athymic nude mice bearing LS174T human colon cancer xenografts. 131I-labeled 17-1A decreased tumor growth in a dose-dependent fashion without lethality. In contrast, the doses of 90Y-labeled 17-1A which were required to produce a significant increase in tumor doubling time also caused marked toxicity. Although similar tumor growth inhibition was produced by 250 μCi 90Y- and 150 μCi 131I-labeled 17-1A, Medical Internal Radiation Dose calculations based on biodistribution data estimated that the dose delivered by 90Y was greater than that delivered by 131I. To investigate this discrepancy, 3-dimensional dose distributions within LS174T tumors were assessed using autoradiography and 3-dimensional calculational techniques. It was found that a greater fraction of the dose was deposited in the tumor after treatment with 131I- compared to 90Y-labeled 17-1A. When the Medical Internal Radiation Dose calculations were adjusted using the 3-dimensional dose distributions, 250 μCi of 90Y- and 150 μCi of 131I-labeled 17-1A were found to deliver similar tumor doses. These studies suggest that 131I-labeled 17-1A is superior to 90Y-labeled 17-1A, since 131I-labeled antibody produced less hematological and animal toxicity and was more effective at inhibiting LS174T tumor growth than 90Y-labeled antibody across the range of radionuclide doses tested. Furthermore, they suggest that it will be necessary to perform 3-dimensional dose calculations. 33 refs., 7 figs., 4 tabs

  1. Label-free capture of breast cancer cells spiked in buffy coats using carbon nanotube antibody micro-arrays

    Science.gov (United States)

    Khosravi, Farhad; Trainor, Patrick; Rai, Shesh N.; Kloecker, Goetz; Wickstrom, Eric; Panchapakesan, Balaji

    2016-04-01

    We demonstrate the rapid and label-free capture of breast cancer cells spiked in buffy coats using nanotube-antibody micro-arrays. Single wall carbon nanotube arrays were manufactured using photo-lithography, metal deposition, and etching techniques. Anti-epithelial cell adhesion molecule (EpCAM) antibodies were functionalized to the surface of the nanotube devices using 1-pyrene-butanoic acid succinimidyl ester functionalization method. Following functionalization, plain buffy coat and MCF7 cell spiked buffy coats were adsorbed on to the nanotube device and electrical signatures were recorded for differences in interaction between samples. A statistical classifier for the ‘liquid biopsy’ was developed to create a predictive model based on dynamic time warping to classify device electrical signals that corresponded to plain (control) or spiked buffy coats (case). In training test, the device electrical signals originating from buffy versus spiked buffy samples were classified with ˜100% sensitivity, ˜91% specificity and ˜96% accuracy. In the blinded test, the signals were classified with ˜91% sensitivity, ˜82% specificity and ˜86% accuracy. A heatmap was generated to visually capture the relationship between electrical signatures and the sample condition. Confocal microscopic analysis of devices that were classified as spiked buffy coats based on their electrical signatures confirmed the presence of cancer cells, their attachment to the device and overexpression of EpCAM receptors. The cell numbers were counted to be ˜1-17 cells per 5 μl per device suggesting single cell sensitivity in spiked buffy coats that is scalable to higher volumes using the micro-arrays.

  2. Investigations into the use of radiolabeled monoclonal antibodies for selective cell labeling in whole blood: Progress report, January 1986-December 1986

    International Nuclear Information System (INIS)

    Techniques to effectively labeling blood cell specific monoclonal antibodies (MAbs), with In-111 using bifunctional chelating agents such as the cyclic or mixed anhydride of diethylenetriaminepentaacetic acid have been developed. Conditions for the optimal labeling of blood cells are reported. The specificity (Kd values) of In-111 labeled MAbs for the cell specific antigens are reported. In-111-MAb labeled canine platelets were used to image vascular thrombi. Under the best experimental conditions approximately 70% of the radiolabeled MAbs get incorporated into isolated blood cells. However, only about 35% of the added MAb-associated radioactivity would incorporate into the desired type of blood cells in whole blood. The chemical nature of the radioactivity that does not bind to the cells was investigated. 9 figs., 6 tabs

  3. Renal uptake of bismuth-213 and its contribution to kidney radiation dose following administration of actinium-225-labeled antibody

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, J; O' Donoghue, J A; Humm, J L [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); Jaggi, J S [Bristol-Myers Squibb, Plainsboro, NJ (United States); Ruan, S; Larson, S M [Nuclear Medicine Service Department of Radiology, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065 (United States); McDevitt, M; Scheinberg, D A, E-mail: schwarj1@mskcc.org [Molecular Pharmacology and Chemistry, Sloan-Kettering Institute, 1275 York Avenue, New York, NY 10065 (United States)

    2011-02-07

    Clinical therapeutic studies using {sup 225}Ac-labeled antibodies have begun. Of major concern is renal toxicity that may result from the three alpha-emitting progeny generated following the decay of {sup 225}Ac. The purpose of this study was to determine the amount of {sup 225}Ac and non-equilibrium progeny in the mouse kidney after the injection of {sup 225}Ac-huM195 antibody and examine the dosimetric consequences. Groups of mice were sacrificed at 24, 96 and 144 h after injection with {sup 225}Ac-huM195 antibody and kidneys excised. One kidney was used for gamma ray spectroscopic measurements by a high-purity germanium (HPGe) detector. The second kidney was used to generate frozen tissue sections which were examined by digital autoradiography (DAR). Two measurements were performed on each kidney specimen: (1) immediately post-resection and (2) after sufficient time for any non-equilibrium excess {sup 213}Bi to decay completely. Comparison of these measurements enabled estimation of the amount of excess {sup 213}Bi reaching the kidney ({gamma}-ray spectroscopy) and its sub-regional distribution (DAR). The average absorbed dose to whole kidney, determined by spectroscopy, was 0.77 (SD 0.21) Gy kBq{sup -1}, of which 0.46 (SD 0.16) Gy kBq{sup -1} (i.e. 60%) was due to non-equilibrium excess {sup 213}Bi. The relative contributions to renal cortex and medulla were determined by DAR. The estimated dose to the cortex from non-equilibrium excess {sup 213}Bi (0.31 (SD 0.11) Gy kBq{sup -1}) represented {approx}46% of the total. For the medulla the dose contribution from excess {sup 213}Bi (0.81 (SD 0.28) Gy kBq{sup -1}) was {approx}80% of the total. Based on these estimates, for human patients we project a kidney-absorbed dose of 0.28 Gy MBq{sup -1} following administration of {sup 225}Ac-huM195 with non-equilibrium excess {sup 213}Bi responsible for approximately 60% of the total. Methods to reduce renal accumulation of radioactive progeny appear to be necessary for the

  4. Diverse characteristics of 111In labelled anti-CEA monoclonal antibodies for tumour immunoscinitigraphy: Radiolabelling, biodistribution and imaging studies in mice with human tumour xenografts

    International Nuclear Information System (INIS)

    Three monoclonal anti-CEA antibodies, designated 161, 198 (both IgG1) and 228 (IgG2a) have been labelled with 111In via DTPA chelation and assessed for localization in human gastro-intestinal carcinomas as xenografts in athymic nude mice. Following reaction of the antibodies with DTPA anhydride, efficiency of chelation of 111In varied between the antibodies with mean values of 30%, 52% and 62% with 161, 198 and 228 respectively. Gel filtration chromatography with all three labelled antibodies showed radiolabel predominantly coincident with IgG with little radioactivity in either high molecular weight form or as free 111In. However, the efficiency of binding of radiolabelled antibodies to CEA producing tumour cells varied, with maxima of 42%, 65% and 20% for 161, 198 and 228. In vivo, in mice, 111In was excreted at virtually identical rates (half times approx. 12 days) with all three prepartions and this was similar to the clearance of indium injected as 111In-indium chloride, but 111In-DTPA was rapidly eliminated (half time approximately 5 h). (orig.)

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

    International Nuclear Information System (INIS)

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

  6. Combination of microwave ablation and 131I labeled tumor necrosis therapy chimeric antibody in the treatment of lung cancer

    International Nuclear Information System (INIS)

    Microwave ablation (MWA) has been considered as an advanced, minimally invasive technique in the treatment of lung cancer with a high local efficiency. MWA can inactivate tumor cells based on microwave heating mechanisms. It has a high local control rate of primary peripheral lung cancer and metastatic lung cancer result from percutaneous microwave antennas injection under ultrasound, CT and MRI guidance. However, for the lesions those are greater than 3.0 cm in diameter or abutting the hilars and the diffuse lesions there is less effective. 131I labeled tumor necrosis therapy chimeric antibody (131I-chTNT), a novel radioimmunotherapy which uses cell of degeneration or necrotic tumor cell nuclear antigen as target provides a new therapeutic approach for lung cancer, but the complete response is low. MWA can induce a mass tumor necrosis under the action of microwave thermal effect which greatly increases the targeting area for 131I-chTNT radioimmunotherapy. Therefore, combination of MWA and 131I-chTNT will enhance the treatment efficacy of lung cancer. (authors)

  7. Detection of pulmonary metastases in a patient with synovial cell sarcoma using In-111 labeled monoclonal antibody 19-24

    International Nuclear Information System (INIS)

    A 35-year-old man was diagnosed in 1984 as having a synovial cell sarcoma of his right wrist without evidence of metastatic spread. The patient underwent regional hyperthermic chemoperfusion, wide-field excision, post-operative radiation therapy and systemic adjuvant chemotherapy. In 1986 and in 1987, because of new lesions found on chest radiographs, the patient underwent bilateral staging thoracotomies with resection of pulmonary metastases, followed by chemotherapy and radiotherapy. Later in 1987, a chest radiograph showed a large left hilar mass and multiple bilateral pulmonary nodules. Computerized tomography of the chest demonstrated a left hilar mass and two nodules in the right lower lung, raising the possibility of recurrent pulmonary metastatic cancer. As a diagnostic procedure, In-111 labeled monoclonal antibody (Mab) 19-24, produced against a human malignant fibrous histiocytoma, was infused intravenously, and 48-hour images revealed focal areas of increased uptake corresponding to the lesions seen on CT. At surgery, the lesions were confirmed to be synovial cell sarcoma. Imaging with Mabs specific for sarcoma may be particularly useful in sarcoma patients in whom there is clinical uncertainty regarding the nature of pulmonary lesions. In this case, the Mab was useful in distinguishing tumor deposits from postsurgical scarring and helped to guide subsequent surgery and treatment

  8. Detection of pulmonary metastases in a patient with synovial cell sarcoma using In-111 labeled monoclonal antibody 19-24

    Energy Technology Data Exchange (ETDEWEB)

    Swift, J.E.; Blend, M.J.; Bekerman, C.; Das Gupta, T.K.; Greager, J.A. (Michael Reese Hospital and Medical Center, Chicago, IL (USA))

    1990-04-01

    A 35-year-old man was diagnosed in 1984 as having a synovial cell sarcoma of his right wrist without evidence of metastatic spread. The patient underwent regional hyperthermic chemoperfusion, wide-field excision, post-operative radiation therapy and systemic adjuvant chemotherapy. In 1986 and in 1987, because of new lesions found on chest radiographs, the patient underwent bilateral staging thoracotomies with resection of pulmonary metastases, followed by chemotherapy and radiotherapy. Later in 1987, a chest radiograph showed a large left hilar mass and multiple bilateral pulmonary nodules. Computerized tomography of the chest demonstrated a left hilar mass and two nodules in the right lower lung, raising the possibility of recurrent pulmonary metastatic cancer. As a diagnostic procedure, In-111 labeled monoclonal antibody (Mab) 19-24, produced against a human malignant fibrous histiocytoma, was infused intravenously, and 48-hour images revealed focal areas of increased uptake corresponding to the lesions seen on CT. At surgery, the lesions were confirmed to be synovial cell sarcoma. Imaging with Mabs specific for sarcoma may be particularly useful in sarcoma patients in whom there is clinical uncertainty regarding the nature of pulmonary lesions. In this case, the Mab was useful in distinguishing tumor deposits from postsurgical scarring and helped to guide subsequent surgery and treatment.

  9. Clinicopathological significance of KI-67 antibody labeling index for patients with squamous cell carcinoma of the esophagus

    International Nuclear Information System (INIS)

    Ki-67 antibody labeling index (MIB-1) is an indicator of cell proliferation, and has been investigated in carcinoma of the lung and breast. However, its correlation with clinicopathological significance and prognosis in squamous cell carcinoma (SCC) of the esophagus has not been determined. Twenty-five patients who underwent potentially curative resection for SCC of the esophagus in the hospital between 2006 and 2008 were enrolled in this study. Patients who had preoperative radio-and/or chemotherapy were excluded. Clinicopathological factors, prognosis of the patients and correlation between the MIB-1 of the primary tumors and the maximum standardized uptake values (max-SUV) in fluorodeoxyglucose positron emission tomography (FDG-PET) were investigated. The mean MIB-1 was 42.3% (range, 13.0-73.2%), and it was significantly correlated with lymph node metastasis (p=0.002) and pathological stage (p=0.007). Patients with high MIB-1 (more than 40%) showed a significantly poor disease-free survival compared with those with low MIB-1 (less than 40%) (p=0.035). Weak correlation was found between the MIB-1 and max-SUV (p=0.051). The MIB-1 has a significant correlation with lymphatic extension and pathological stage, and can be a prognostic parameter. MaxSUV might be a predictive factor of prognosis. (author)

  10. Development of a label-free SPR sensor for detection of matrixmetalloproteinase-9 by antibody immobilization on carboxymethyldextran chip.

    Science.gov (United States)

    Mohseni, Sara; Moghadam, Tahereh Tohidi; Dabirmanesh, Bahareh; Jabbari, Safoura; Khajeh, Khosro

    2016-07-15

    Surface plasmon resonance (SPR) immunosensor has been widely utilized for monitoring antigen-antibody interactions. The sensor measures changes of refractive index upon binding of analyte molecules to specific ligand immobilized on the sensor chip. This effort reports development of SPR immunosensor for real-time and label-free detection of recombinant human matrix metalloproteinases-9 (MMP-9), which has been associated with malignant tumor progression and metastasis by matrix degradation. MMP-9 was expressed in Escherichia coli BL21 and purified by Ni-NTA agarose column. CMD 50 D was activated by EDC/NHS for immobilization of monoclonal anti-MMP-9. Atomic force microscopy images showed uniform distribution of anti-MMP-9 over the sensor chip. Equilibrium constant (KD), maximum binding capacity (Rmax) and ∆Gb values for interaction of MMP-9 and anti-MMP-9 were 0.4nM, 680 µRIU and -53.51kJ/mol, respectively. Concentration of MMP-9 in saliva samples was determined, with linearity in the range of 10-200ng/mL. The limit of detection was found to be 8pg/mL, being lower than most of the previously reported techniques. PMID:27016912

  11. Preparation of {sup 105}Rh labeled monoclonal antibody (MAb B72.3) using aminobenzylpropyleneamineoxime as the bifunctional chelating agent; comparison to {sup 131}I labeled MAb B72.3

    Energy Technology Data Exchange (ETDEWEB)

    Venkatesh, M. [Bhabha Atomic Research Centre, Bombay (India). Isotope Div.; Schlemper, E.O.; Jurisson, S.S. [Missouri Univ., Columbia, MO (United States). Dept. of Chemistry; Ketring, A.R. [Missouri Univ. Research Reactor, Columbia, MO (United States); Volkert, W.A. [Missouri Univ., Columbia, MO (United States). Radiology Research; H.S. Truman Memorial VA Hospital, Columbia, MO (United States); Corlija, M. [H.S. Truman Memorial VA Hospital, Columbia, MO (United States)

    1999-07-01

    Monoclonal antibody(MAb) B72.3 was labeled with {sup 105}Rh using aminobenzylpropyleneamineoxime (PnAO-{phi}-NH{sub 2}) as the bifunctional chelating agent. {sup 105}Rh-PnAO-{phi}-NH{sub 2} was formed at {proportional{underscore}to} 80 C at pH 5-6 and purified by extraction into chloroform. The excess unreacted ligand was retained in the aqueous phase by addition of Cu{sup 2+} ions by forming a charged complex. The amine group on {sup 105}Rh complex was activated and conjugated with MAb at pH 8.5 {proportional{underscore}to}90% complexation and 40-60% conjugation were realised. Radiolabeled antibody was purified by gel filtration. B72.3 MAb was labeled with {sup 131}I and used for comparison of biodistribution in normal mice. (orig.)

  12. Tumor immunolocalization using {sup 124}I-iodine-labeled JAA-F11 antibody to Thomsen-Friedenreich alpha-linked antigen

    Energy Technology Data Exchange (ETDEWEB)

    Chaturvedi, Richa [Department of Biotechnical and Clinical Laboratory Sciences, University at Buffalo, StateUniversity of New York, Buffalo, NY 14214 (United States); Heimburg, Jamie [Department of Microbiology and Immunology, University at Buffalo, StateUniversity of New York, Buffalo, NY 14214 (United States); Yan, Jun; Koury, Stephen [Department of Biotechnical and Clinical Laboratory Sciences, University at Buffalo, StateUniversity of New York, Buffalo, NY 14214 (United States); Sajjad, Munawwar; Abdel-Nabi, Hani H. [Department of Nuclear Medicine, University at Buffalo, StateUniversity of New York, Buffalo, NY 14214 (United States); Rittenhouse-Olson, Kate [Department of Biotechnical and Clinical Laboratory Sciences, University at Buffalo, StateUniversity of New York, Buffalo, NY 14214 (United States); Department of Microbiology and Immunology, University at Buffalo, StateUniversity of New York, Buffalo, NY 14214 (United States)], E-mail: krolson@buffalo.edu

    2008-03-15

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

  13. Label-Free and Real-Time Detection of Antigen-Antibody Capture Processes Using the Oblique-Incidence Reflectivity Difference Technique

    International Nuclear Information System (INIS)

    We successfully label-free and real-time detect the capture processes of human immunoglobulin G (IgG)/goat anti-human IgG and mouse IgG/goat anti-mouse IgG antigen-antibody pairs with different concentrations using the oblique-incidence reflectivity difference (OIRD) method, and obtain the interaction kinetics curves and the interaction times. The experimental results prove that the OIRD method is a promising technique for label-free and real-time detection of the biomolecular interaction processes and achieving the quantitative information of interaction kinetics. (general)

  14. Label-Free and Real-Time Detection of Antigen-Antibody Capture Processes Using the Oblique-Incidence Reflectivity Difference Technique

    Science.gov (United States)

    He, Li-Ping; Dai, Jun; Sun, Yue; Wang, Jing-Yi; Lü, Hui-Bin; Wang, Shu-Fang; Jin, Kui-Juan; Zhou, Yue-Liang; Yang, Guo-Zhen

    2012-07-01

    We successfully label-free and real-time detect the capture processes of human immunoglobulin G (IgG)/goat anti-human IgG and mouse IgG/goat anti-mouse IgG antigen-antibody pairs with different concentrations using the oblique-incidence reflectivity difference (OIRD) method, and obtain the interaction kinetics curves and the interaction times. The experimental results prove that the OIRD method is a promising technique for label-free and real-time detection of the biomolecular interaction processes and achieving the quantitative information of interaction kinetics.

  15. Positively charged templates for labeling internalizing antibodies: comparison of N-succinimidyl 5-iodo-3-pyridinecarboxylate and the D-amino acid peptide KRYRR

    Energy Technology Data Exchange (ETDEWEB)

    Foulon, Catherine F.; Welsh, Philip C.; Bigner, Darell D.; Zalutsky, Michael R. E-mail: zalut001@mc.duke.edu

    2001-10-01

    Receptor-mediated internalization of monoclonal antibodies (mAbs), such as those specific for the epidermal growth factor receptor variant III (EGFRvIII), can lead to rapid loss of radioactivity from the target cell. In the current study, the anti-EGFRvIII mAb L8A4 was radioiodinated using two methods -N-succinimidyl 5-iodo-3-pyridinecarboxylate (SIPC) and via a D-amino acid peptide LysArgTyrArgArg (D-KRYRR). Paired-label internalization assays performed on EGFRvIII-expressing U87{delta}EGFR cells in vitro demonstrated that labeling L8A4 using D-KRYRR resulted in significantly higher retention of radioiodine in the intracellular compartment. In athymic mice with D256 human glioma xenografts, tumor uptake was similar for both labeling methods through 24 hr. However, an up to fourfold higher tumor retention was observed for mAb labeled with the D-amino acid peptide at later time points. Radiation absorbed dose calculations based on these biodistribution data indicated that L8A4 labeled using D-KRYRR exhibited better tumor-to-normal-organ radiation dose ratios, suggesting that this labeling method may be of particular value for labeling internalizing mAbs.

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

    DEFF Research Database (Denmark)

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

    2014-01-01

    UNLABELLED: Alpha-particle emitters, such as astatine-211 (211At), are generally considered suitable for the treatment of small cell clusters due to their short path length, while beta-particle emitters, for example, Lutetium-177 (177Lu), have a longer path length and are considered better for...... small, established tumors. A combination of such radionuclides may be successful in regimens of radioimmunotherapy. In this study, rats were treated by sequential administration of first a 177Lu-labeled antibody, followed by a 211At-labeled antibody 25 days later. METHODS: Rats bearing solid colon...... carcinoma tumors were treated with 400 MBq/kg body weight 177Lu-BR96. After 25 days, three groups of animals were given either 5 or 10 MBq/kg body weight of 211At-BR96 simultaneously with or without a blocking agent reducing halogen uptake in normal tissues. Control animals were not given any 211At-BR96...

  17. Enzyme-linked immunosorbent assay that uses labeled antigen for detection of immunoglobulin M and A antibodies in toxoplasmosis: comparison with indirect immunofluorescence and double-sandwich enzyme-linked immunosorbent assay.

    OpenAIRE

    van Loon, A M; Van der Logt, J. T.; Heessen, F W; van der Veen, J.

    1983-01-01

    A direct enzyme-linked immunosorbent assay (ELISA) is described that uses horseradish peroxidase-labeled antigen for detection of immunoglobulin M (IgM) and IgA antibodies to toxoplasma. In this assay, polystyrene microtiter plates were sensitized with anti-human IgM or IgA antibody to separate IgM or IgA from other classes of antibody. The presence of IgM or IgA antibodies to toxoplasma (Tox-IgM, Tox-IgA) was then detected by sequential addition of soluble horseradish peroxidase-labeled toxo...

  18. Radioimmunoimaging of non-small cell lung cancer with [sup 111]In- and [sup 99m]Tc-labeled monoclonal anti-CEA antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Kairemo, K.J.A. (Dept. of Clinical Chemistry, Helsinki Univ. Central Hospital (Finland)); Aronen, H.J. (Dept. of Radiology, Helsinki Univ. Central Hospital (Finland)); Liewendahl, K. (Dept. of Clinical Chemistry, Helsinki Univ. Central Hospital (Finland)); Paavonen, T. (Dept. of Pathology, Helsinki Univ. Central Hospital (Finland)); Heikkonen, J.J. (Dept. of Radiotherapy and Oncology, Helsinki Univ. Central Hospital (Finland)); Virkkunen, P. (Dept. of Radiotherapy and Oncology, Helsinki Univ. Central Hospital (Finland)); Maeki-Hokkonen, H. (Dept. of Radiotherapy and Oncology, Helsinki Univ. Central Hospital (Finland)); Karonen, S.L. (Dept. of Clinical Chemistry, Helsinki Univ. Central Hospital (Finland)); Brownell, A.L. (Dept. of Clinical Chemistry, Helsinki Univ. Central Hospital (Finland)); Maentylae, M.J. (Dept. of Radiotherapy and Oncology, Helsinki Univ. Central Hospital (Finland))

    1993-01-01

    Radiolabeled monoclonal anti-CEA antibodies were used for radioimmunolocalization (RIL) of non-small cell lung cancer; in 30 patients with [sup 111]In labeled anti CEA F(ab')[sub 2] fragment (BW 431/31) and in 16 with [sup 99m]Tc-labeled intact MoAb (BW 431/26). RIL results were compared with those of other imaging modalities. Paraffin sections from some patients were also studied immunohistochemically using anti-CEA antibody. Patients with [sup 111]In labeled MoAB were imaged twice 1-4 days after injection and for image enhancement pulmonary and liver/spleen subtraction were performed. Twenty-seven of 28 primary tumors were positive and metastases were detected in all patients. The total number of lesions was 78 of which 61 (78%) could be detected by RIL. For verification CT was applied to the study of 46 lesions detected by RIL. We found 6 unknown lesions subsequently verified histologically. Using subtraction techniques we detected 9 lesions in 4 patients, later verified as plumonary metastases, not detected in unprocessed images. Pleural, mediastinal and pericardial lesions were also better delineated in subtracted images than in unprocessed images. Imaging of non-small cell lung cancer with [sup 99m]Tc-labeled MoAB was performed twice 4-24 h after injection. RIL results were compared with other imaging methods; CT US, conventional radiography, and immunohistochemistry. Twelve out of 16 patients with suspected or known lung cancer had positive immunoscintigrams; 19 of 25 lesions could be detected by RIL. There were 5 false positive and 2 true negative findings. Immunoperoxidase (IP) stainings of paraffin sections of the tumours from 7 patients were performed using two different anti-CEA antibodies; BW 431/26 and ZCEA[sub 1]. None of the seven tumors examined by immunohistochemistry were negative when stained by BW 431/26, which was the antibody used for immunoscintigraphy. (orig.).

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

    International Nuclear Information System (INIS)

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

  20. p-carboxyethyl-phenylglyoxal bis(n-methylthiosemicarbazone) (CE-DTS), a bifunctional chelating agent for Tc-99m labeled monoclonal antibody

    International Nuclear Information System (INIS)

    In the search for bifunctional chelating agents (BCA) with better affinity, selectivity and stability as for Tc-99m, synthesis of a novel BCA containing di-thio-semicarbazone as for Tc-99m chelating site has offered interesting characteristics for the labeling of macromolecules. In the present paper, monoclonal IgG (MoAb) against human thyroglobulin was selected as a model and conditions for coupling, labeling reactions were tested along with immunological reactivity. CE-DTS was coupled to MoAb by the azido method and effect of conjugation on the MoAb immunoreactivity was followed by RIA. When CE-DTS was coupled to MoAb at the molar ratio of 1:1, no loss of its original immunoreactivity was observed. Tc-99m labeling, using the stannous ion reducing method, indicated the reaction pH as being a determinant parameter. The reducing agent prepared in tartrate buffer (pH 3) offered high yield and stable Tc-99m-CE-DTS-MoAb, as evidence by HPLC. In vivo studies in mice indicated percent of injected dose and blood clearance alike the I-131-MoAb. This good labeled state of Tc-99m-CE-DTS-MoAb was also demonstrated by using second antibody reaction in serum of mice. The newly synthesized CE-DTS offered good basis for the Tc-99m labeling of monclonal antibodies with preserved immunological properties, as desirable for the radioimmunodetection. Work with tumor related monoclonal antibodies is under progress

  1. Anti-CEA monoclonal antibody: technetium-99m labeling and the validation process of a scintigraphic animal model with a non-cellular antigenic implant.

    Science.gov (United States)

    Sapienza, Marcelo Tatit; Marques, Fabio Luiz Navarro; Okamoto, Miriam Roseli Yoshie; Hironaka, Fausto Haruki; Buchpiguel, Carlos Alberto

    2002-07-01

    Animal models are currently used to verify the biodistribution of different radiopharmaceuticals before its clinical application in Nuclear Medicine; however, there may be some limitations. The utilization of labelled anti-tumor monoclonal antibodies (MoAb) in experimental models often requires implant of human antigens (usually a cellular implant), which cannot be achieved in immunocompetent animals. Our purpose was to label an anti-CEA MoAb with technetium-99m (99Tc) and to validate a simplified animal model using a noncellular antigenic implant. MoAb was directly labelled with 99mTc, after reduction with 2-mercaptoethanol. Labeling efficiency was checked by ascending chromatography and immunoreactive fraction was measured in plastic wells sensitized with the antigen. Radiopharmaceutical biodistribution was evaluated by dissection and scintigraphy in 5 mice groups; following the subcutaneous administration of Al(OH)3, CEA adsorbed Al(OH)2 and a control group evaluation. Labeling efficiency was 94+/-3%, which showed to be stable for 24 hr, with immunoreactive fraction above 50%. Invasive biodistribution evaluation showed prolonged blood retention, hepatic and renal uptake. A significant increase in uptake was observed in scintigraphic studies of animals with CEA-adsorbed Al(OH)3 implants compared with the other groups (p<0.05). The non-cellular antigenic implant model simplifies the pre-clinical evaluation of labelled MoAb. PMID:12146705

  2. Chronic complicated osteomyelitis of the appendicular skeleton: diagnosis with technetium-99m labelled monoclonal antigranulocyte antibody-immunoscintigraphy

    International Nuclear Information System (INIS)

    Chronic post-traumatic osteomyelitis (OM) represents a particular challenge for nuclear medicine and radiology since clinical and biochemical parameters are frequently unreliable. The aim of this study was to investigate the value of combined bone scan (BS) and immunoscintigraphy (IS) with technetium-99m labelled monoclonal antigranulocyte antibody (MAB) in patients with suspected chronic OM of the appendicular skeleton. Twenty-four patients (17 females and 7 males) with suspected chronic post-traumatic OM were evaluated with three-phase BS/99mTc-MAB-IS. The final diagnosis was established by means of bone culture and histology in 19 cases and clinical follow-up in five cases. The studies were reviewed by two independent and experienced observers; the interobserver agreement was calculated by kappa statistics. The sensitivity, specificity and accuracy of BS alone were 92%, 18% and 58%, respectively. Combined BS/99mTc-MAB-IS had a sensitivity, specificity and accuracy of 84%, 72% and 79%, respectively. Of 24 studies, 11 were true-positive, two false-negative, eight true-negative and three false-positive. Two patients presented with unexpected ectopic haematopoietic bone marrow in the appendicular skeleton that caused false-positive results. A high degree of interobserver agreement was found (κ=0.85). It is concluded that combined BS/99mTc-MAB-IS represents a very sensitive and reproducible method with an acceptable specificity for the investigation of chronic OM. Problems may occur in the differentiation of low-grade OM from aseptic inflammation. Another problem is ectopic marrow that may occur in the appendicular skeleton due to a chronic inflammatory stimulus. A former intramedullary intervention in the femur with displacement of haematopoietic marrow may also lead to an ectopic location. (orig.). With 2 figs., 1 tab

  3. Internal radiation dosimetry, pharmacokinetics and biodistribution of the 99mTc labeled ior egf/r3 monoclonal antibody

    International Nuclear Information System (INIS)

    The aim of this work was to assess the internal radiation dosimetry, human pharmacokinetics and biodistribution of the 99mTc-labeled murine monoclonal antibody (MAb) ior egf/r3, used for diagnosis of epithelial tumors. Five patients were included in this study. Multiple blood and urine samples were collected and sequential anterior and posterior whole-body scintigraphies up to 24 hr post-injection were acquired from all patients. The internal radiation dosimetry was estimated using the methods developed by the Medical Internal Radiation Dosimetry (MIRD) committee. Raw data were computed from operations between scintigraphic images and regions of interest (ROI). The residence times of the activity on the source organs were computed to assess the absorbed dose by 24 target organs. The dosimetric results showed that liver, gallbladder and spleen received the higher absorbed dose. The computed mean values were 0.69 mGy/MBq, 0.19mGy/MBq and 0.37 mGy/MBq, respectively. The mean value of effective dose was 1,2E-01 mSv/MBq and the effective equivalent dose was 9,2E-02 mSv/MBq. The pharmacokinetics and biodistribution results showed that this compound has a biexponential plasmatic and blood clearance with a rapid biodistribution phase and a slower elimination phase. This compound was excreted by the urinary and hepatobiliary systems. Liver was the principal target organ of this product showing a great retention of the MAb. These dosimetric results have allowed to use the ior egf/r3 kit in a safe and controlled way. (author)

  4. Contribution of tryptophan residues to the combining site of a monoclonal anti dinitrophenyl spin-label antibody

    International Nuclear Information System (INIS)

    Two Fab fragments of the monoclonal anti dinitrophenyl (DNP) spin-label antibody AN02 were prepared by recombination of specifically deuterated heavy and light chains. In the recombinant H(I)L(II) all the tyrosines and phenylalanines were perdeuterated as were the tryptophan residues of the heavy chain. In the recombinant H(II)L(I) all the tyrosines and phenylalanines were perdeuterated as were the tryptophan residues of the light chain. Saturation of three resonances of H(I)L(II), assigned to tryptophan protons of the light chain, resulted in magnetization transfer to the aromatic proton at position 6 of the DNP ring and to the CH2 protons of the glycines linked to the DNP in a diamagnetic hapten (DNP-DG). Saturation of three resonances of H(II)L(I) assigned to tryptophan protons of the heavy chain resulted in magnetization transfer to the CH2 protons of the glycines in DNP-DG. From the dependence of the magnetization transfer on the irradiation time, the cross relaxation rates between the involved protons were estimated. The inferred distances between these protons of the hapten and certain tryptophan protons are 3-4 A. It is concluded that in the combining site of AN02 there is one tryptophan from the light chain and one tryptophan from the heavy chain that are very near the hapten. When all tyrosines and phenylalanines were perdeuterated and all tryptophan aromatic protons were deuterated except for the protons at positions 2 and 5, titration of the Fab fragments with variable amounts of paramagnetic hapten showed that one proton from the light chain tryptophan is near (less than 7 A) the unpaired electron and that three other protons are significantly closer than 15 A

  5. 166Ho and 90Y labeled 6D2 monoclonal antibody for targeted radiotherapy of melanoma: Comparison with 188Re radiolabel

    International Nuclear Information System (INIS)

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

  6. Highly sensitive enzyme-free immunosorbent assay for porcine circovirus type 2 antibody using Au-Pt/SiO2 nanocomposites as labels.

    Science.gov (United States)

    Wu, Long; Yin, Wenmin; Tang, Kun; Shao, Kang; Li, Qin; Wang, Pan; Zuo, Yunpeng; Lei, Xiaomin; Lu, Zhicheng; Han, Heyou

    2016-08-15

    Improving the performance of conventional enzyme-linked immunosorbent assay (ELISA) is of great importance to meet the demand of early clinical diagnosis of various diseases. Herein, we report a feasible enzyme-free immunosorbent assay (EFISA) system using antibody conjugated Au-Pt/SiO2 nanocomposites (APS NCs) as labels. In this system, Au-Pt/SiO2 nanospheres (APS NPs) were first synthesized by wet chemical method and exhibited intrinsic peroxidase and catalase-like activity with excellent water-solubility. Then APS NCs were utilized as labels to replace HRP conjugated antibody, and Fe3O4 magnetic beads (MBs) to entrap the analyte. To discuss the performance of EFISA system, Human IgG was served as a model analyte, and porcine circovirus type 2 (PCV2) serums as real samples. The system boosted the detection limit of HIgG to 75pgmL(-1) with a RSD below 5%, a 264-fold improvement as compared with conventional ELISA. This is the first time that APS NCs have been used and successfully optimized for the sensitive dilution detection of PCV2 antibody (5:10(7)) in ELISA. Besides, APS NCs have advantages related to low cost, easy preparation, good stability and tunable catalytic activity, which make them a potent enzyme mimetic candidate and may find potential applications in bioassays and clinical diagnostics. PMID:27085949

  7. Radioimmunoimaging of experimental thrombi in dogs using Tc-99m labeled monoclonal antibody fragments [MAPab-F(ab')/sub 2/] reactive with human platelets

    International Nuclear Information System (INIS)

    Radioimmunoimaging of thrombi could have great clinical value in the management of coronary artery and thromboembolic disease. In-111-oxine-labeled platelets currently used require platelet isolation, delayed imaging, background subtraction and there is also potential for damaging or contaminating platelets during labeling. Murine monoclonal antibody (IgG/sub 2/a) fragments directed against human platelet membrane components (cross-reactive with dog platelets) were labeled with Tc-99m and repurified from ''kits''. After radiolabeling, 91.5-93.3% of the Tc-99m was antibody-associated. The preparations retained immunoreactivity, as determined by the ratio of cell to plasma-associated radioactivity (ratios 54.7-63.8). Tc-99m-MAPAb-F(ab')/sub 2/ were injected i.v. into dogs with thrombi produced in peripheral and pulmonary veins and arteries. About 50% of the radioactivity was cleared from the blood in 3-6 min. and 18-24% was excreted in the urine within 3 hrs. The thrombi were consistently and easily visible within 1-3 hrs. with no need for blood pool subtraction. In some cases, intimal damage along the path of catheters was seen. No adverse side effects were observed. The advantages of this method are: short and simple preparation, no need for blood pool subtraction and early visualization of thrombi. Human studies are warranted to determine its clinical efficacy

  8. Development of a method to measure kinetics of radiolabelled monoclonal antibody in human tumour with applications to microdosimetry: positron emission tomography studies of iodine-124 labelled 3F8 monoclonal antibody in glioma

    International Nuclear Information System (INIS)

    We present a method to assess quantitatively the immuhological characteristics of tumours using radiolabelled monoclonal antibody and positron emission tomography (PET) to improve dosimetry for radioimmunotherapy. This method is illustrated with a glioma patient who injected with 96.2 MPq of iodine-124 labelled 3FB, a murine antibody (IgG3) specific against the ganglioside GD2. Serial PET scans and plasma samples were taken over 11 days. A three-compartment model was used to estimate the plasma to tumour transfer constant (K1), the tumour to plasma transfer constant k2, the association and dissociation constants (k3, k4) of antibody binding, and the binding potential. Tumour radioactivity peaked at 18 h at 0.0045% ID/g. The kinetic parameters were estimated to be: K1=0.048 ml h-1 g-1, k2=0.16 h-1, k3=0.03 h-1, k4=0.015 h-1 and BP=2.25. Based on these kinetic parameters, the amount of tumour-bound radiolabelled monoclonal antibody was calculated. This method permits estimates of both macrodosimetry and microdosimetry at the cellular level based on in vivo non-invasive measurement. (orig.)

  9. Application of the indirect enzyme-labeled antibody microtest to the detection and surveillance of animal diseases. [Brucellosis, cholera, and trichinosis in cattle and swine

    Energy Technology Data Exchange (ETDEWEB)

    Saunders, G.C. Clinard, E.H.; Bartlett, M.L.; Sanders, W.M.

    1976-01-01

    The rapid, indirect enzyme-labeled antibody (ELA) microplate test has been developed as a diagnostic and surveillance tool to aid in the control of animal disease. Data are presented, which illustrate the application of the test to viral (hog cholera), parasitic (trichinosis), and bacterial (brucellosis) diseases of animals. A greater than 95 percent correlation was observed between the hog cholera ELA test and the hog cholera serum neutralization test performed on over 2000 mixed hog cholera positive and negative field samples obtained during the 1976 New Jersey epizootic. Of 56 swine naturally infected with Trichinella spiralis at a level considered dangerous to man, all were ELA positive, while only one of 360 T. spiralis negative packing house sera was ELA positive. Preliminary experiments with bovine brucellosis (Brucella abortus) indicate that the ELA test is more sensitive than other test methods currently in use. ELA procedures should soon become tests of choice for the detection of antibodies to animal disease agents.

  10. Label-free and real-time detection of antigen-antibody interactions by Oblique-incidence Reflectivity Difference (OIRD) method

    Science.gov (United States)

    He, LiPing; Sun, Yue; Dai, Jun; Wang, JingYi; Lü, HuiBin; Wang, ShuFang; Jin, KuiJuan; Zhou, YueLiang; Yang, GuoZhen

    2012-09-01

    We label-free and real-time detected three interaction processes of antigen-antibodies, Human Immunoglobulin G (IgG), Rabbit IgG, and Mouse IgG as the targets, and Goat Anti-human IgG, Goat Anti-rabbit IgG, and Goat Anti-mouse IgG as the probe, by the Oblique-incidence Reflectivity Difference (OIRD) method. The interaction dynamic curves of the OIRD signal, corresponding to the interaction processes of antigen-antibodies, are generated. The reaction times from beginning to equilibrium state are about 1800, 900, and 1200 s for Human IgG, Rabbit IgG, and Mouse IgG, respectively. The experimental results demonstrate that the OIRD method not only can distinguish biomolecular interactions, but also can be used in real-time detection of interactions and dynamic processes of biomolecules.

  11. Development of indirect competitive fluorescence immunoassay for 2,2′,4,4′-tetrabromodiphenyl ether using DNA/dye conjugate as antibody multiple labels

    Institute of Scientific and Technical Information of China (English)

    Zi-Yan Fan; Young Soo Keum; Qing-Xiao Li; Weilin L. Shelver; Liang-Hong Guo

    2012-01-01

    An indirect competitive fluorescence immunoassay using a DNA/dye conjugate as antibody multiple labels was developed on 96-well plates for the identification and quantification of 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) in aqueous samples.A hapten,2,4,2′-tribromodiphenyl ether-4′-aldehyde,was synthesized,and was conjugated to bovine serum albumin to form a coating antigen,Specific recognition of the antigen by anti-PBDE antiserum was confirmed by a surface plasmon resonance measurement.In the immunoassay,the coating antigen was adsorbed on a 96-well plate first,and a sample,antiserum and biotinylated goat anti-rabbit secondary antibody were then added and reacted sequentially.A biotinylated,double-stranded DNA with 219 base pairs was attached to the secondary antibody by using streptavidin as a molecular bridge.In situ multiple labeling of the antibody was accomplished after addition of a DNA-binding fluorescent dye,SYBR Green I.The working range of the immunoassay for the BDE-47 standard was 3.1-390 μg/L,with an IC50 value of 15.6 μg/L.The calculated LOD of the immunoassay is 0.73 μg/L.The immunoassay demonstrated relatively high selectivity for BDE-47,showing very low cross-reactivity (< 3%) with BDE-15,BDE-153 and BDE-209.With a spiked river water sample containing 50 μg/L BDE-47,quantification by the immunoassay was 41.9 μg/L,which compared well with the standard GC-ECD method (45.7 μg/L).The developed immunoassay provides a rapid screening tool for polybrominated diphenyl ethers in environmental samples.

  12. Preliminary study on guiding therapy of subcutaneous human hetero graft in nude mice by 211-At labelled monoclonal antibody against gastric cancer

    International Nuclear Information System (INIS)

    In short time, 211At labelled monoclonal antibody 3H11 inhibited the growth of human gastric cancer grafted in nude mice effectively. The most evident inhibition was observed at the 9th day after treatment, and the tumor inhibition rates were 80%, 93%, 48% in the groups of intravenous injection, internal tumor injection (both 211At-3H11 5 μCi per animal), Na211 At (5 μCi per animal) treatment respectively. On the 20th day, when animals were killed, the tumor inhibition rates were 66%, 81%, 6%, respectively. Inhibition treated with Na211At showed obviously lower than those at the 9th day

  13. Positron Emission Tomography Imaging of Tumor Angiogenesis with a 61/64Cu-Labeled F(ab')2 Antibody Fragment

    OpenAIRE

    Hong, Hao; Zhang, Yin; Orbay, Hakan; Valdovinos, Hector F.; Nayak, Tapas R.; Bean, Jero; Theuer, Charles P.; Barnhart, Todd E.; Cai, Weibo

    2013-01-01

    The objective of this study was to characterize the in vitro and in vivo properties of the F(ab')2 fragment of TRC105, a human/murine chimeric IgG1 monoclonal antibody that binds with high avidity to human and murine CD105 (i.e. endoglin), and investigate its potential for positron emission tomography (PET) imaging of tumor angiogenesis after 61/64Cu-labeling. TRC105-F(ab')2 of high purity was produced by pepsin digestion of TRC105, which was confirmed by SDS-PAGE, HPLC analysis, and mass spe...

  14. Biodistribution and preparation of technetium-99m-labeled D-D3 monoclonal antibody against pro-gastrin-releasing peptide (31-98) in mice

    Institute of Scientific and Technical Information of China (English)

    HAO Li-jun; HONG Zhi-hui; SHI Yi-zhen; LIU Zeng-li; ZHOU Xiao-lin

    2013-01-01

    Background We previously reported that iodine-131(131I)-labeled anti-pro-gastrin-releasing peptide (ProGRP(31-98)) monoclonal antibody D-D3 could selectively accumulate in the tumor sites of nude mice bearing small cell lung cancer (SCLC) xenografts.However,131I-D-D3 was cleared slowly from the body,and the best radioimmunoimaging time for SCLC was 72-96 hours after injection.The aims of this study were to radiolabel anti-ProGRP(31-98) D-D3 monoclonal antibody with technetium-99m (99mTc) and to investigate the biodistribution of this antibody in healthy ICR mice.Methods D-D3 was labeled with 99mTc via the 2-mercaptoethanol reduction method.99mTc-D-D3 was purified by the gel column separation method.The labeling efficiency and radiochemical purity were measured by thin-layer chromatography.The immunological activity of 99mTc-D-D3 was determined with cell conjugation assays.99mTc-D-D3 was injected into healthy ICR mice via a tail vein,and all the healthy ICR mice were sacrificed by cervical dislocation at a designated time.Then,the blood and major organs were removed and weighed,and counted in a gamma scintillation counter to determine the percentage of the injected dose per gram (%ID/g).Results The labeling rate and the radiochemical purity of 99mTc-D-D3 were (73.87±2.89)% and (94.13±4.49)%,respectively.The immunobinding rates of 99mTc-D-D3 to the human small cell lung cancer NCl-H446 cell line and lung adenocarcinoma A549 cell line were (81.2±2.37)% and (24.3±1.46)%,respectively.The distribution data of normal ICR mice demonstrated that 99mTc-D-D3 was mainly distributed in the liver,kidney and lung,and less in the brain tissue and muscle.Conclusions 99mTc-D-D3 antibody not only had high radiochemical purity,but also had good stability both in vitro and in vivo,and maintained good immunological activity.99mTc-D-D3 was metabolized mainly in the kidney and liver,and the blood radioactivity decreased rapidly.Thus,99mTc-D-D3 is conducive to the

  15. Development of a simple and selective separation of 67Cu from irradiated zinc for use in antibody labelling: a comparison of methods

    International Nuclear Information System (INIS)

    A procedure for the production and separation of Cu isotopes from irradiated Zn was developed. Following a comparison of methods based on extraction, electrolysis and ion-exchange chromatography, a technique for the separation of Cu employing three ion-exchange matrices was developed which was simple, reproducible and hot cell-compatible. The specific activity of the final product was 37 MBq 67Cu/μg Cu at EOB. The level of impurities was so low that no interference with antibody labelling was observed. (author)

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

    Directory of Open Access Journals (Sweden)

    Ann-Marie eWaldron

    2016-03-01

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

  17. {sup 177}Lu-labeled-VG76e monoclonal antibody in tumor angiogenesis: a comparative study using DOTA and DTPA chelating systems

    Energy Technology Data Exchange (ETDEWEB)

    Fani, M.; Psimadas, D. [Inst. of Radioisotopes and Radiodiagnostic Products, National Centre for Scientific Research ' ' Demokritos' ' , Athens (Greece); Biomedica Life Sciences S.A., Athens (Greece); Bouziotis, P.; Gourni, E.; Varvarigou, A.D. [Inst. of Radioisotopes and Radiodiagnostic Products, National Centre for Scientific Research ' ' Demokritos' ' , Athens (Greece); Harris, A.L. [Weatherall Inst. of Molecular Medicine, Cancer Research U.K., Univ. of Oxford (United Kingdom); Loudos, G. [Biomedical Simulations and Imaging Lab., National Technical Univ. of Athens (Greece); Maecke, H.R. [Div. of Radiological Chemistry, Univ. Hospital Basel (Switzerland)

    2007-07-01

    Vascular endothelial growth factor (VEGF) is one of the molecules which regulate angiogenesis, a phenomenon observed in many diseases, including cancer. VG76e, an anti-VEGF monoclonal antibody, was labeled with {sup 177}Lu via p-SCN-Bz-DOTA and CHX-A''-DTPA chelating systems, in order to investigate its possible therapeutic use. Labeling was performed by a 30 min incubation of {sup 177}LuCl{sub 3} and each immunoconjugate, at 37 C. Radiochemical analysis showed the formation of a single radioactive species, at a yield higher than 98%, for both immunoconjugates. Kits have been formulated for both VG76e-DOTA and VG76e-DTPA. Stability studies, in the presence of a competitor excess, showed that both radiolabeled species remained sufficiently stable (95%) for at least 48 h. Biodistribution results in normal mice were similar for both radioimmunoconjugates, with no significant bone uptake. Gamma camera images of tumor-bearing mice showed satisfactory visualization of the tumor 24 h p.i., while a higher uptake was observed at 48 h p.i. Our findings indicate that both the bifunctional chelating agents p-SCN-Bz-DOTA and CHX-A''-DTPA can be used for the labeling of VG76e with {sup 177}Lu, with high labeling yield and stability. Their in vivo behaviour in normal and tumor-bearing mice looks promising and they can be successfully used for tumor imaging studies. (orig.)

  18. Behaviour of iodine-125 labelled monoclonal anti-TSH and cellulose linked (solid phase) antibodies in a supersensitive TSH IRMA

    International Nuclear Information System (INIS)

    The quality of reagents used in supersensitive immunoradiometric assay (IRMA) for thyroid stimulating hormone (TSH) is of great significance to determine low concentrations of TSH in human serum samples. A sandwich IRMA TSH in-house assay procedure was developed at the Institute of Nuclear Medicine and Oncology Lahore. Two specific antibodies were involved in this assay system; one antibody was (MAb) 125I radiolabelled, while the second antibody was covalently coupled to cellulose. Results presented in the paper describe the behaviour of these two reagents in this assay system and their importance in monitoring low detection levels of TSH. 12 refs, 3 figs, 3 tabs

  19. γδ T cell-mediated antibody-dependent cellular cytotoxicity with CD19 antibodies assessed by an impedance-based label-free real-time cytotoxicity assay

    Directory of Open Access Journals (Sweden)

    Ursula Jördis Eva Seidel

    2014-12-01

    Full Text Available γδ T cells are not MHC restricted, elicit cytotoxicity against various malignancies, are present in early post-transplant phases in novel stem cell transplantation (SCT strategies and have been shown to mediate antibody-dependent cellular cytotoxicity (ADCC with monoclonal antibodies (mAbs. These features make γδ T cells promising effector cells for antibody-based immunotherapy in pediatric patients with B-lineage acute lymphoblastic leukemia (ALL. To evaluate combination of human γδ T cells with CD19 antibodies for immunotherapy of B-lineage ALL, γδ T cells were expanded after a GMP-compliant protocol and ADCC of both primary and expanded γδ T cells with an Fc optimized CD19 antibody (4G7SDIE and a bispecific antibody with the specificities CD19 and CD16 (N19-C16 was evaluated in CD107a degranulation assays and intracellular cytokine staining (ICS. CD107a, TNF-α and IFN-γ expression of primary γδ T cells were significantly increased and correlated with CD16-expression of γδ T cells. γδ T cells highly expressed CD107a after expansion and no further increased expression by 4G7SDIE and N19-C16 was measured. Cytotoxicity of purified expanded γδ T cells targeting CD19-expressing cells was assessed in both europium-TDA release and in an impedance-based label-free method (using the xCELLigence system measuring γδ T cell lysis in real-time. Albeit in the 2 h end-point europium-TDA release assay no increased lysis was observed, in real-time xCELLigence assays both significant antibody-independent cytotoxicity and ADCC of γδ T cells were observed. The xCELLigence system outperformed the end-point europium-TDA release assay in sensitivity and allows drawing of conclusions to lysis kinetics of γδ T cells over prolonged periods of time periods. Combination of CD19 antibodies with primary as well as expanded γδ T cells exhibits an promising approach, which may enhance clinical outcome of patients with pediatric B-lineage ALL and

  20. γδ T Cell-Mediated Antibody-Dependent Cellular Cytotoxicity with CD19 Antibodies Assessed by an Impedance-Based Label-Free Real-Time Cytotoxicity Assay.

    Science.gov (United States)

    Seidel, Ursula Jördis Eva; Vogt, Fabian; Grosse-Hovest, Ludger; Jung, Gundram; Handgretinger, Rupert; Lang, Peter

    2014-01-01

    γδ T cells are not MHC restricted, elicit cytotoxicity against various malignancies, are present in early post-transplant phases in novel stem cell transplantation strategies and have been shown to mediate antibody-dependent cellular cytotoxicity (ADCC) with monoclonal antibodies (mAbs). These features make γδ T cells promising effector cells for antibody-based immunotherapy in pediatric patients with B-lineage acute lymphoblastic leukemia (ALL). To evaluate combination of human γδ T cells with CD19 antibodies for immunotherapy of B-lineage ALL, γδ T cells were expanded after a GMP-compliant protocol and ADCC of both primary and expanded γδ T cells with an Fc-optimized CD19 antibody (4G7SDIE) and a bi-specific antibody with the specificities CD19 and CD16 (N19-C16) was evaluated in CD107a-degranulation assays and intracellular cytokine staining. CD107a, TNFα, and IFNγ expression of primary γδ T cells were significantly increased and correlated with CD16-expression of γδ T cells. γδ T cells highly expressed CD107a after expansion and no further increased expression by 4G7SDIE and N19-C16 was measured. Cytotoxicity of purified expanded γδ T cells targeting CD19-expressing cells was assessed in both europium-TDA release and in an impedance-based label-free method (using the xCELLigence system) measuring γδ T cell lysis in real-time. Albeit in the 2 h end-point europium-TDA release assay no increased lysis was observed, in real-time xCELLigence assays both significant antibody-independent cytotoxicity and ADCC of γδ T cells were observed. The xCELLigence system outperformed the end-point europium-TDA release assay in sensitivity and allows drawing of conclusions to lysis kinetics of γδ T cells over prolonged periods of time periods. Combination of CD19 antibodies with primary as well as expanded γδ T cells exhibits a promising approach, which may enhance clinical outcome of patients with pediatric B-lineage ALL and requires clinical

  1. Pulse labeling of small nuclear ribonucleoproteins in vivo reveals distinct patterns of antigen recognition by human autoimmune antibodies.

    OpenAIRE

    Fisher, D E; Reeves, W H; Conner, G E; Blobel, G; Kunkel, H. G.

    1984-01-01

    Antibodies directed against small nuclear ribonucleoprotein ( snRNP ) particles are found in the Sm and RNP autoimmune sera from numerous patients with systemic lupus erythematosus (SLE) and mixed connective tissue disease (MCTD). These two reactivities differ in disease distribution as well as antigen specificity. Although sera from both of these autoimmune syndromes contain snRNP reactive antibodies, distinction in antigen binding specificity have been difficult to define because of the par...

  2. Labeling internalizing anti-epidermal growth factor receptor variant III monoclonal antibody with 177Lu: in vitro comparison of acyclic and macrocyclic ligands

    International Nuclear Information System (INIS)

    Introduction: The monoclonal antibody (mAb) L8A4, reactive with the epidermal growth factor receptor variant III (EGFRvIII), internalizes rapidly in glioma cells after receptor binding. Combining this tumor-specific mAb with the low-energy β-emitter 177Lu would be an attractive approach for brain tumor radioimmunotherapy, provided that trapping of the radionuclide in tumor cells after mAb intracellular processing could be maximized. Materials and Methods: L8A4 mAb was labeled with 177Lu using the acyclic ligands [(R)-2-amino-3-(4-isothiocyanatophenyl)propyl]-trans-(S,S) -cyclohexane-1,2-diamine-pentaacetic acid (CHX-A''-DTPA), 2-(4-isothiocyanatobenzyl)-diethylenetriaminepenta-acetic acid (pSCN-Bz-DTPA) and 2-(4-isothiocyanatobenzyl)-6-methyldiethylenetriaminepentaacetic acid (1B4M-DTPA), and the macrocyclic ligands S-2-(4-isothiocyanatobenzyl)-1,4,7,10-tetraazacyclododecane-tetraacetic acid (C-DOTA) and α-(5-isothiocyanato-2-methoxyphenyl)-1,4,7,10-tetraazacyclododecane-1,4,7, 10-tetraacetic acid (MeO-DOTA). Paired-label internalization and cellular processing assays were performed on EGFRvIII-expressing U87.ΔEGFR glioma cells over 24 h to directly compare 177Lu-labeled L8A4 to L8A4 labeled with 125I using either iodogen or N-succinimidyl 4-guanidinomethyl-3-[125I]iodobenzoate ([125I]SGMIB). In order to facilitate comparison of labeling methods, the primary parameter evaluated was the ratio of 177Lu to 125I activity retained in U87.ΔEGFR cells. Results: All chelates demonstrated higher retention of internalized activity compared with mAb labeled using iodogen, with 177Lu/125I ratios of >20 observed for the three DTPA chelates at 24 h. When compared to L8A4 labeled using SGMIB, except for MeO-DOTA, internalized activity for 125I was higher than 177Lu from 1-8 h with the opposite behavior observed thereafter. At 24 h, 177Lu/125I ratios were between 1.5 and 3, with higher values observed for the three DTPA chelates. Conclusions: The nature of the chelate used to

  3. Two newly developed methods for the radioactive labeling of tetanus toxins with substances emitting beta-rays and the usefulness of the compounds thus obtained in radioimmunoassays to determine tetanus antibodies

    International Nuclear Information System (INIS)

    Described are two methods to label tetanus toxins using either 14C-formaldehyde or succinimidyl-3H- propionate as radioactive tracers. The question as to whether the labeled compounds thus obtained can be introduced into RIAs for the detection of tetanus antibodies is also discussed. The immunoreactivity of 3H-toxin is not perceptibly changed by the labeling procedure. The compound can be compared to 125I-labeled toxin, although it suffers no adverse effects from long-term due to autoradiolysis. (TRV)

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

    International Nuclear Information System (INIS)

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

  5. Intraindividual comparison of {sup 99m}Tc-labelled anti-SSEA-1 antigranulocyte antibody and {sup 99m}Tc-HMPAO labelled white blood cells for the imaging of infection

    Energy Technology Data Exchange (ETDEWEB)

    Gratz, S.; Behr, T.; Herrmann, A.; Becker, W. [Goettingen Univ. (Germany). Abt. fuer Nuklearmedizin; Dresing, K.; Stuermer, K.M. [Department of Trauma, Plastic and Reconstructive Surgery, University of Goettingen (Germany); Tarditi, L.; Franceschini, R. [SORIN Biomedica, Saluggia (Italy); Rhodes, B. [RHOMED, Albuquerque, New Mexiko (United States)

    1998-04-01

    The aim of this study was to compare the diagnostic accuracy of the {sup 99m}Tc-anti-SSEA-1 Mab with that of {sup 99m}Tc-HMPAO labelled white blood cells (WBCs). To this end, 17 patients with 23 proven infectious foci were examined with 555 MBq {sup 99m}Tc-anti-SSEA-1 MAb and with 370 MBq {sup 99m}Tc-HMPAO labelled autologous leucocytes within a period of 7 days. All the infections were confirmed by culturd of 7 days. Whole-body images and planar spot views with the antibody were performed at 1-h, 4-h and 24-h post injection; the biodistribution of the antibody was quantified, absorbed radiation doses were calculated and the diagnostic results were compared with the {sup 99m}Tc-HMPAO WBC images. Human anti-mouse antibody (HAMA) evaluation was performed in all patients before and 3 months after antibody injection. Blood was drawn at different times after {sup 99m}Tc-anti-SSEA-1 MAb injection to determine the amount of granulocyte-associated radioactivity and to calculate recovery. {sup 99m}Tc-anti-SSEA-1 MAb scintigraphy detected all 23 lesions, while 21 were detected with {sup 99m}Tc-HMPAO WBC scan. In this small group of patients, the sensitivity and specificity of {sup 99m}Tc-anti-SSEA-1 MAb scintigraphy were 95% and 96% respectively, as compared with 91% and 82% respectively for {sup 99m}Tc-HMPAO WBC scan. An increasing uptake of the injected activity in the lesion at different time points was indicative of high affinity and of specific PMN binding.There was no HAMA formation. In four of five patients investigated, a transient mild leukopenia was found at 15 min p.i. There was increased uptake of the antibody in liver and spleen and normal uptake in kidneys and bone marrow.The estimated radiation doses for the whole body and the red bone marrow were 1.1 x 10{sup -2} cGy/37 MBq and 5.3 x 10{sup -2} cGy/37 MBq, respectively. The activity associated to the PMNs in vivo was 33.5%, 30.6%, 21.3% and 9% at 5, 15, 30 and 45 min. post-injection, respectively

  6. Imaging cancer using PET - the effect of the bifunctional chelator on the biodistribution of a {sup 64}Cu-labeled antibody

    Energy Technology Data Exchange (ETDEWEB)

    Dearling, Jason L.J., E-mail: jason.dearling@childrens.harvard.ed [Division of Nuclear Medicine and Department of Radiology, Children' s Hospital Boston, 300 Longwood Avenue, Boston, MA 02115 (United States); Harvard Medical School, Boston, MA 02115 (United States); Voss, Stephan D. [Division of Nuclear Medicine and Department of Radiology, Children' s Hospital Boston, 300 Longwood Avenue, Boston, MA 02115 (United States); Harvard Medical School, Boston, MA 02115 (United States); Dunning, Patricia; Snay, Erin [Division of Nuclear Medicine and Department of Radiology, Children' s Hospital Boston, 300 Longwood Avenue, Boston, MA 02115 (United States); Fahey, Frederic [Division of Nuclear Medicine and Department of Radiology, Children' s Hospital Boston, 300 Longwood Avenue, Boston, MA 02115 (United States); Harvard Medical School, Boston, MA 02115 (United States); Smith, Suzanne V. [Australian National Science and Technology Organisation (ANSTO), New Illawarra Road, PMB1, Menai, New South Wales 2234 (Australia); Huston, James S. [EMD Serono Research Center, 45A Middlesex Turnpike, Billerica, MA 01821-3936 (United States); Boston Biomedical Research Institute, Watertown, MA 02472-2899 (United States); Meares, Claude F. [Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616-5295 (United States); Treves, S. Ted; Packard, Alan B. [Division of Nuclear Medicine and Department of Radiology, Children' s Hospital Boston, 300 Longwood Avenue, Boston, MA 02115 (United States); Harvard Medical School, Boston, MA 02115 (United States)

    2011-01-15

    Introduction: Use of copper radioisotopes in antibody radiolabeling is challenged by reported loss of the radionuclide from the bifunctional chelator used to label the protein. The objective of this study was to investigate the relationship between the thermodynamic stability of the {sup 64}Cu-complexes of five commonly used bifunctional chelators (BFCs) and the biodistribution of an antibody labeled with {sup 64}Cu using these chelators in tumor-bearing mice. Methods: The chelators [S-2-(aminobenzyl)1,4,7-triazacyclononane-1,4,7-triacetic acid (p-NH{sub 2}-Bn-NOTA): 6-[p-(bromoacetamido)benzyl]-1, 4, 8, 11-tetraazacyclotetradecane-N, N', N'', N'''-tetraacetic acid (BAT-6): S-2-(4-aminobenzyl)-1,4,7,10-tetraazacyclododocane tetraacetic acid (p-NH{sub 2}-Bn-DOTA): 1,4,7,10-tetraazacyclododocane-N, N', N', N''-tetraacetic acid (DOTA): and 1-N-(4-aminobenzyl)-3,6,10,13,16,19-hexaazabicyclo[6.6.6]eicosane-1, 8-diamine (SarAr)] were conjugated to the anti-GD2 antibody ch14.18, and the modified antibody was labeled with {sup 64}Cu and injected into mice bearing subcutaneous human melanoma tumors (M21) (n = 3-5 for each study). Biodistribution data were obtained from positron emission tomography images acquired at 1, 24 and 48 hours post-injection, and at 48 hours post-injection a full ex vivo biodistribution study was carried out. Results: The biodistribution, including tumor targeting, was similar for all the radioimmunoconjugates. At 48 h post-injection, the only statistically significant differences in radionuclide uptake (p < 0.05) were between blood, liver, spleen and kidney. For example, liver uptake of [{sup 64}Cu]ch14.18-p-NH{sub 2}-Bn-NOTA was 4.74 {+-} 0.77 per cent of the injected dose per gram of tissue (%ID/g), and for [{sup 64}Cu]ch14.18-SarAr was 8.06 {+-} 0.77 %ID/g. Differences in tumor targeting correlated with variations in tumor size rather than which BFC was used. Conclusions: The results of this

  7. Comparative studies of antibody anti-CD20 labeled with {sup 188}Re; Estudo comparativo da marcacao do anticorpo anti-CD20 com {sup 188}Re

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Carla Roberta de Barros Rodrigues

    2010-07-01

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

  8. [3H]Azidodantrolene photoaffinity labeling, synthetic domain peptides and monoclonal antibody reactivity identify the dantrolene binding sequence on RyR1

    Energy Technology Data Exchange (ETDEWEB)

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

    2002-06-14

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

  9. Expression profile of vascular cell adhesion molecule-1 (CD106) in inflammatory foci using rhenium-188 labelled monoclonal antibody in mice.

    Science.gov (United States)

    Kairemo, K J; Strömberg, S; Nikula, T K; Karonen, S L

    1998-06-01

    Rhenium (Re)-188 is a generator (W-188/Re-188) produced high energy beta-emitter suitable for radionuclide therapy (T1/2 is 16.9 hrs and Emax 2.1 MeV (range 11 mm)). We have labelled monoclonal antibody (MAb) raised against vascular cell adhesion molecule-1 (VCAM-1) with Re-188 using glucoheptonate chelation technique and SnCl2 as reducing agent. The labelling efficiency, free perrhenate and reduced Re were controlled with thin layer chromatography and the purification of Re-188-MoAbs was performed using gel filtration. Our results indicate that Re-188-labelled antibodies remain in vitro stable and the labelling purity is > 90%. We also have applied these Re-188-MoAbs for detection of inflammatory disease in a mouse. The effective half-lives of organs of interest after an injection of Re-188-anti-VCAM1 were as follows: blood 5.2 hr, kidney 4.7 hr, and liver 9.6 hr. Re-188-anti-VCAM-1 was found to accumulate mainly in kidney and liver. One hour after the injection, the kidney contained in average as high as 12.5% and the liver 2.8 ID/g tissue. After 6 hr, the kidney contained 5.5% ID/g and the liver 2.6% ID/g. At 24 hr, the kidney uptake was 0.5% ID/g and the liver uptake 0.8% ID/g, respectively. The inflamed foci, subcutaneous lesions in the footpad skin, were visualized using gamma camera. From the distribution data the uptakes in the inflamed foci as follows: at 1 hr 2.18 (inflammation) and 1.72% ID/g (control), at 6 hr 1.42 (inflammation) and 0.85% ID/g (control), and at 24 hr 0.17 (inflammation) and 0.084% ID/g (control), respectively. Anti-VCAM-1 MAb showed better targeting as compared to control MoAbs in inflammation (caused by E.coli lipoplysaccaride). In conclusion, Re-188 is suitable for MAb labelling, and MAb against VCAM-1 may be used for detection of local inflammatory disease. PMID:9762472

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

    International Nuclear Information System (INIS)

    Objective: To study the in vitro immunoreactivity and in vivo tissue distribution, tumor targeting property of anti-human bladder tumor human-murine chimeric antibody (ch-BDI) labeled with 99Tcm and to investigate its possibility for being used in guiding diagnosis and guiding therapy of bladder cancer. Methods: The ch-BDI was labeled with 99Tcm by improved Schwarz method and the labeled antibody was purified by Sephadex G-50. Labeling yield and radiochemical purity were measured by paper chromatography. The immunoreactive fraction and association constant (Ka) were measured by Lindmo method and Scatchard analysis, respectively. 11.1 MBq (30 μg) 99Tcm-ch-BDI was intravenously injected into nude mice bearing human bladder cancer xenografts in the right thigh and radioimmunoimaging (RII) was performed 2, 6, 20 and 24 h postinjection. The images were processed by region of interest (ROI) method to acquire the counts of whole body and the tumor and the counts ratios of tumor to contralateral normal tissue or to tissues of other non-tumor bearing organs. The mice were killed after 24 h postinjection imaging and tissue distribution was measured. %ID/g and target to nontarget (T/NT) ratios were calculated. Results: The labeling yield and radiochemical purity of 99Tcm-ch-BDI were (66.5±7.3)% and >90%, respectively. The immunoreactive fraction was 76% and Ka was 3.56 x 109 L/mol. RII showed that the tumor was clearly visualized 6 h postinjection and becoming clearer along with time prolonging. The radioactivity of whole body decreased rapidly with time, whereas the radioactivity of the tumor decreased slowly. The T/NT ratios was increased with time. Biodistribution results showed that tumor uptake was 17.4%ID/g 24 h postinjection. T/NT ratios were very high except for the kidney. T/NT ratios for brain, muscle, intestinal wall, bone and heart wall were 136.0, 55.1, 39.3, 29.7 and 27.9, respectively. Conclusion: 99Tcm-ch-BDI exhibits excellent immunoreactivity and tumor

  11. Horseradish peroxidase and antibody labeled gold nanoparticle probe for amplified immunoassay of ciguatoxin in fish samples based on capillary electrophoresis with electrochemical detection.

    Science.gov (United States)

    Zhang, Zhaoxiang; Liu, Ying; Zhang, Chaoying; Luan, Wenxiu

    2015-03-01

    This paper describes a new amplified immunoassay with horseradish peroxidase (HRP) and antibody (Ab) labeled gold nanoparticles (AuNPs) probe hyphenated to capillary electrophoresis (CE) with electrochemical (EC) detection for ultrasensitive determination of ciguatoxin CTX1B. AuNPs were conjugated with HRP and Ab, and then incubated with limited amount of CTX1B to produce immunocomplex. The immunoreactive sample was injected into capillary for CE separation and EC detection. Enhanced sensitivity was obtained by adopting the AuNPs as carriers of HRP and Ab at high HRP/Ab molar ratio. The calibration curve of CTX1B was in the range of 0.06-90 ng/mL. The detection limit was 0.045 ng/mL, which is 38-fold lower than that of HPLC-MS method for CTX1B analysis. The proposed method was successfully applied for the quantification of CTX1B in contamined fish samples by simultaneously labeling Ab and HRP on AuNPs. The amplified IA with HRP and Ab labeled AuNPs probe hyphenated to CE and EC detection provides a sensitive analytical approach for the determination of trace ciguatoxin in complex samples. PMID:25637767

  12. Improved labelling of DTPA- and DOTA-conjugated peptides and antibodies with 111In in HEPES and MES buffer.

    OpenAIRE

    Brom, Maarten; Joosten, Lieke; Oyen, Wim JG; Gotthardt, Martin; Boerman, Otto C

    2012-01-01

    ABSTRACT: BACKGROUND: In single photon emission computed tomography [SPECT], high specific activity of 111In-labelled tracers will allow administration of low amounts of tracer to prevent receptor saturation and/or side effects. To increase the specific activity, we studied the effect of the buffer used during the labelling procedure: NaAc, NH4Ac, HEPES and MES buffer. The effect of the ageing of the 111InCl3 stock and cadmium contamination, the decay product of 111In, was also examined in th...

  13. Detection of magnetic-labeled antibody specific recognition events by combined atomic force and magnetic force microscopy

    Science.gov (United States)

    Hong, Xia; Liu, Yanmei; Li, Jun; Guo, Wei; Bai, Yubai

    2009-09-01

    Atomic force (AFM) and magnetic force microscopy (MFM) were developed to detect biomolecular specific interaction. Goat anti-mouse immunoglobulin (anti-IgG) was covalently attached onto gold substrate modified by a self-assembly monolayer of thioctic acid via 1-ethyl-3-[3-(dimethylamino) propyl] carbodiimide (EDC) activation. Magnetic-labeled IgG then specifically adsorbed onto anti-IgG surface. The morphological variation was identified by AFM. MFM was proved to be a fine assistant tool to distinguish the immunorecognized nanocomposites from the impurities by detection of the magnetic signal from magnetic-labeled IgG. It would enhance the understanding of biomolecular recognition process.

  14. Detection of magnetic-labeled antibody specific recognition events by combined atomic force and magnetic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Hong Xia [Center for Advanced Optoelectronic Functional Materials Research, Key Laboratory of UV Light-Emitting Materials and Technology, Ministry of Education, Northeast Normal University, Changchun 130024 (China); College of Chemistry, Jilin University, Changchun 130023 (China)], E-mail: xiahong@nenu.edu.cn; Liu Yanmei; Li Jun; Guo Wei; Bai Yubai [College of Chemistry, Jilin University, Changchun 130023 (China)

    2009-09-15

    Atomic force (AFM) and magnetic force microscopy (MFM) were developed to detect biomolecular specific interaction. Goat anti-mouse immunoglobulin (anti-IgG) was covalently attached onto gold substrate modified by a self-assembly monolayer of thioctic acid via 1-ethyl-3-[3-(dimethylamino) propyl] carbodiimide (EDC) activation. Magnetic-labeled IgG then specifically adsorbed onto anti-IgG surface. The morphological variation was identified by AFM. MFM was proved to be a fine assistant tool to distinguish the immunorecognized nanocomposites from the impurities by detection of the magnetic signal from magnetic-labeled IgG. It would enhance the understanding of biomolecular recognition process.

  15. Detection of magnetic-labeled antibody specific recognition events by combined atomic force and magnetic force microscopy

    International Nuclear Information System (INIS)

    Atomic force (AFM) and magnetic force microscopy (MFM) were developed to detect biomolecular specific interaction. Goat anti-mouse immunoglobulin (anti-IgG) was covalently attached onto gold substrate modified by a self-assembly monolayer of thioctic acid via 1-ethyl-3-[3-(dimethylamino) propyl] carbodiimide (EDC) activation. Magnetic-labeled IgG then specifically adsorbed onto anti-IgG surface. The morphological variation was identified by AFM. MFM was proved to be a fine assistant tool to distinguish the immunorecognized nanocomposites from the impurities by detection of the magnetic signal from magnetic-labeled IgG. It would enhance the understanding of biomolecular recognition process.

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

    Energy Technology Data Exchange (ETDEWEB)

    Patil, Vishwesh; Gada, Keyur; Panwar, Rajiv; Ferris, Craig; Khaw, Ban-An [Northeastern University, School of Pharmacy, Department of Pharmaceutical Sciences, Boston, MA (United States); Varvarigou, Alexandra [Institute of Radioisotopes and Radiodiagnostics, National Centre for Scientific Research ' ' Demokritos' ' , Athens (Greece); Majewski, Stan [West Virginia University, Department of Radiology, Nuclear Medicine Imaging Instrumentation Program, Center for Advanced Imaging, Morgantown, WV (United States); Weisenberger, Andrew [Jefferson LA, Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Tekabe, Yared [Columbia University Medical Center, New York, NY (United States)

    2012-05-15

    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 {sup 111}In- or {sup 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. {sup 111}In-Labeled DTPA-succinyl polylysine (DSPL) was injected intravenously at 24 h (7.03 {+-} 1.74 or 6.88 {+-} 1.89 MBq {sup 111}In-DSPL) after Bom-bsCx or 50 {+-} 5.34 MBq of {sup 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 {sup 111}In or {sup 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 {sup 111}In-DSPL injection. No lesions were visualized in Bom or anti-DTPA Ab pretargeted controls. {sup 111}In-DSPL activity in Bom-bsCx pretargeted tumors (1

  17. Immunoscintigraphy of human neuroblastoma xenografted in nude mice using a panel of 125I-labelled monoclonal antibodies

    International Nuclear Information System (INIS)

    Neuroblastoma is the most frequent tumour of the childhood under the age of 5. The staging and the follow up are achieved by MIBG scintigraphy, considered as the method of reference, but sometimes difficult to interpret. The availability of monoclonal antibodies against the ganglioside GD2, expressed on the cell membrane of neuroblastoma and neuro-endocrine cancers offers novel tools that deserve to be carefully explored. We investigated four mouse monoclonal antibodies (3 lgG3: BW704, 7A4, 60C3, and the lgG1 variant of BW704: MAK704), on nude mice xenografted with a human neuroblastoma (REM). Sixty one nude mice were included. The three former MAbs provided tumour imaging, the best results being obtained with BW704, followed by 7A4 and 60C3. MAK704 was disappointing. A control antiphosphorylcholine antibody (P51-1) did not give any tumour image in the three tested mice. Scintigraphy ratios tumour/liver and tumour/muscle reached 20 and 100 with BW704, respectively, on the 10th day. Good imaging quality was already obtained from the 24th h. The tumour uptake, calculated from radioactivity countings of resected samples, reached 22 ± 3% of injected dose per gram. These results let us hope that these antibodies could also provide highly contrasted images in humans and could open the way for therapeutic applications. (authors). 18 refs., 6 figs., 1 tab

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

    International Nuclear Information System (INIS)

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

  19. Improved labelling of DTPA- and DOTA-conjugated peptides and antibodies with 111In in HEPES and MES buffer.

    NARCIS (Netherlands)

    Brom, M.; Joosten, L.; Oyen, W.J.G.; Gotthardt, M.; Boerman, O.C.

    2012-01-01

    ABSTRACT: BACKGROUND: In single photon emission computed tomography [SPECT], high specific activity of 111In-labelled tracers will allow administration of low amounts of tracer to prevent receptor saturation and/or side effects. To increase the specific activity, we studied the effect of the buffer

  20. Specific tumor labeling enhanced by polyethylene glycol linkage of near infrared dyes conjugated to a chimeric anti-carcinoembryonic antigen antibody in a nude mouse model of human pancreatic cancer

    Science.gov (United States)

    Maawy, Ali A.; Hiroshima, Yukihiko; Zhang, Yong; Luiken, George A.; Hoffman, Robert M.; Bouvet, Michael

    2014-10-01

    Labeling of metastatic tumors can aid in their staging and resection of cancer. Near infrared (NIR) dyes have been used in the clinic for tumor labeling. However, there can be a nonspecific uptake of dye by the liver, lungs, and lymph nodes, which hinders detection of metastasis. In order to overcome these problems, we have used two NIR dyes (DyLight 650 and 750) conjugated to a chimeric anti-carcinoembryonic antigen antibody to evaluate how polyethylene glycol linkage (PEGylation) can improve specific tumor labeling in a nude mouse model of human pancreatic cancer. The conjugated PEGylated and non-PEGylated DyLight 650 and 750 dyes were injected intravenously into non-tumor-bearing nude mice. Serum samples were collected at various time points in order to determine serum concentrations and elimination kinetics. Conjugated PEGylated dyes had significantly higher serum dye concentrations than non-PEGylated dyes (p=0.005 for the 650 dyes and ppancreatic tumors subcutaneously implanted into nude mice were labeled with antibody-dye conjugates and serially imaged. Labeling with conjugated PEGylated dyes resulted in significantly brighter tumors compared to the non-PEGylated dyes (p<0.001 for the 650 dyes; p=0.01 for 750 dyes). PEGylation of the NIR dyes also decreased their accumulation in lymph nodes, liver, and lung. These results demonstrate enhanced selective tumor labeling by PEGylation of dyes conjugated to a tumor-specific antibody, suggesting their future clinical use in fluorescence-guided surgery.

  1. High contrast tumor imaging with radio-labeled antibody Fab fragments tailored for optimized pharmacokinetics via PASylation

    OpenAIRE

    Mendler, Claudia T; Friedrich, Lars; Laitinen, Iina; Schlapschy, Martin; Schwaiger, Markus; Wester, Hans-Jürgen; Skerra, Arne

    2014-01-01

    Although antigen-binding fragments (Fabs) of antibodies constitute established tracers for in vivo radiodiagnostics, their functionality is hampered by a very short circulation half-life. PASylation, the genetic fusion with a long, conformationally disordered amino acid chain comprising Pro, Ala and Ser, provides a convenient way to expand protein size and, consequently, retard renal filtration. Humanized αHER2 and αCD20 Fabs were systematically fused with 100 to 600 PAS residues and produced...

  2. Kinetics and immunocytochemical dyeing of monoclonal 99mTc-labelled anti-CEA-antibodies against granulocytes after intravenous administration

    International Nuclear Information System (INIS)

    Until now the clinical identification of the affinity of monoclonal 99mTc-anti-CEA antibodies (MAK BW 250/183) on granulocytes was made with tumor cells carrying the same epitope on NCA-95 and human granulocytes in vitro. As this antibody only binds human granulocytes in vitro. As this antibody only binds human granulocytes, animal experiments are impossible. 3 patients had their blood withdrawn within 6 h after injection, another patient had his left hip-joint biopsied after 24 h, the samples undergoing subsequent immunocytochemical dyeing. Dyeing of granulocytes all over the smears was evident whereas lymphocytes, monocytes and erythrocytes did not show any reaction. After 6 h there seemed to be a large difference between a relatively high quantity of 86% unlabelled 99mTc-MAb and 75% of immunocytochemically stainable granulocytes in the blood through an excess of binding epitopes. Six h after injection 27% of the activity were, on average, detectable in whole blood. At this time the activity in blood was reduced to an extent that scintigraphic imaging was feasible. (orig.)

  3. Radioimmunoimaging of human colon carcinoma grafted into nude mice using 131I-labeled monoclonal anti-CEA antibody (C50)

    International Nuclear Information System (INIS)

    131I-labeled monoclonal anti-CEA antibody C50 was injected intraperitoneally into nude mice bearing human colon carcinoma xenografts for tumor localization and radioimmunoimaging studies. Radioimmunoimaging and biodistribution was performed at the 1st, 2nd, 3th, 4th and 6th day after injection and transplanted tumors were visualized in 24 hr by SPECT. Satisfactory tumor imaging was obtained at 48 hr after injection and at the 6th day T/NT (tumor/colon) reached 10.40 +- 0.69. These in vivo studies demonstrate the specificity of McAb C50 and indicate that it may be used for clinical diagnosis and targeting treatment of human colon carcinoma

  4. Phospho-specific recognition by 14-3-3 proteins and antibodies monitored by a high throughput label-free optical biosensor.

    Science.gov (United States)

    Wu, Meng; Coblitz, Brian; Shikano, Sojin; Long, Shunyou; Spieker, Matt; Frutos, Anthony G; Mukhopadhyay, Sunil; Li, Min

    2006-10-16

    Label-free detection of molecular interactions has considerable potential in facilitating assay development. When combined with high throughput capability, it may be applied to small molecule screens for drug candidates. Phosphorylation is a key posttranslational process that confers diverse regulation in biological systems involving specific protein-protein interactions recognizing the phosphorylated motifs. Using a resonant waveguide grating biosensor, the Epic mark System, we have developed a generic assay to quantitatively measure phospho-specific interactions between a trafficking signal-phosphorylated SWTY peptide and 14-3-3 proteins or anti-phosphopeptide antibodies. Compared with a solution-based fluorescence anisotropy assay, our results support that the high throughput resonant waveguide grating biosensor system has favorable technical profiles in detecting protein-protein interactions that recognize phosphorylated motifs. Hence it provides a new generic HTS platform for phospho-detection. PMID:17011553

  5. Pharmacokinetics, biodistribution and dosimetry of 99mTc-labeled anti-human epidermal growth factor receptor humanized monoclonal antibody R3 in rats

    International Nuclear Information System (INIS)

    The pharmacokinetics, biodistribution and dosimetry of 99mTc-labeled anti-human epidermal growth factor receptor (anti-hEGF-r) humanized monoclonal antibody (MAb) R3 was investigated following intravenous injection in normal Wistar rats. Serum disappearance curves were best fit by a two-compartment model having a mean distribution half-life (t(1(2α))) of 0.250 h and a mean elimination (t(1(2β))) of 13.89 h. Among the various organs, a little accumulation of the radiolabeled antibody was found only in kidneys. Biodistribution and dosimetry studies in humans were performed by extrapolation of the animal data to humans. Absorbed dose to normal organs and the remainder of the whole body were estimated using the medical internal radiation dose formula, and dose contributions from radioactivity in transit through the gastrointestinal tract were estimated using a compartment model. Extrapolated values of radiation absorbed dose to normal organs in rads per millicurie administered were whole body, 0.0085; lower large intestine wall, 0.0898; small intestine, 0.0530; upper large intestine wall, 0.0731; and kidneys, 0.0455. The effective dose equivalent predicted was 0.0162 rem/mCi and the effective dose was found to be 0.015 rem/mCi. On the basis of the pharmacokinetics, biodistribution and internal radiation dosimetry information obtained in this study, a diagnostic phase I clinical trial with 99mTc-labeled humanized MAb R3 conjugate in patients should be supported

  6. In vivo photoacoustic imaging of cancer using indocyanine green-labeled monoclonal antibody targeting the epidermal growth factor receptor.

    Science.gov (United States)

    Sano, Kohei; Ohashi, Manami; Kanazaki, Kengo; Ding, Ning; Deguchi, Jun; Kanada, Yuko; Ono, Masahiro; Saji, Hideo

    2015-08-28

    Photoacoustic (PA) imaging is an attractive imaging modality for sensitive and depth imaging of biomolecules with high resolution in vivo. The aim of this study was to evaluate the effectiveness of an anti-epidermal growth factor receptor (EGFR) monoclonal antibody (panitumumab; Pan) labeled with indocyanine green derivative (ICG-EG4-Sulfo-OSu), Pan-EG4-ICG, as a PA imaging probe to target cancer-associated EGFR. In vitro PA imaging studies demonstrated that Pan-EG4-ICG yielded high EGFR-specific PA signals in EGFR-positive cells. To determine the optimal injection dose and scan timing, we investigated the biodistribution of radiolabeled Pan-EG4-ICG (200-400 μg) in A431 tumor (EGFR++)-bearing mice. The highest tumor accumulation (29.4% injected dose/g) and high tumor-to-blood ratio (2.1) was observed 7 days after injection of Pan-EG4-ICG (400 μg). In in vivo PA imaging studies using Pan-EG4-ICG (400 μg), the increase in PA signal (114%) was observed in A431 tumors inoculated in the mammary glands 7 days post-injection. Co-injection of excess Pan resulted in a 35% inhibition of this PA signal, indicating the EGFR-specific accumulation. In conclusion, the ICG-labeled monoclonal antibody (i.e., panitumumab) has the potential to enhance target-specific PA signal, leading to the discrimination of aggressiveness and metastatic potential of tumors and the selection of effective therapeutic strategies. PMID:26168727

  7. Electrogenerated chemiluminescence biosensing for the detection of prostate PC-3 cancer cells incorporating antibody as capture probe and ruthenium complex-labelled wheat germ agglutinin as signal probe

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Haiying [Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi’an 710062 (China); Department of Chemistry, Yuncheng University, Yuncheng 044300 (China); Li, Zhejian; Shan, Meng; Li, Congcong; Qi, Honglan; Gao, Qiang [Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi’an 710062 (China); Wang, Jinyi [College of Science and College of Veterinary Medicine, Northwest A& F University, Yangling 712100 (China); Zhang, Chengxiao, E-mail: cxzhang@snnu.edu.cn [Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi’an 710062 (China)

    2015-03-10

    Highlights: • A novel biosensor was developed for the detection of prostate cancer cells. • The selectivity of the biosensor was improved using antibody as capture probe. • The biosensor showed the low extremely detection limit of 2.6 × 10{sup 2} cells mL{sup −1}. • The ruthenium complex-labelled WGA can be transported in the cell vesicles. - Abstract: A highly selective and sensitive electrogenerated chemiluminescence (ECL) biosensor for the detection of prostate PC-3 cancer cells was designed using a prostate specific antibody as a capture probe and ruthenium complex-labelled wheat germ agglutinin as a signal probe. The ECL biosensor was fabricated by covalently immobilising the capture probe on a graphene oxide-coated glassy carbon electrode. Target PC-3 cells were selectively captured on the surface of the biosensor, and then, the signal probe was bound with the captured PC-3 cells to form a sandwich. In the presence of tripropylamine, the ECL intensity of the sandwich biosensor was logarithmically directly proportion to the concentration of PC-3 cells over a range from 7.0 × 10{sup 2} to 3.0 × 10{sup 4} cells mL{sup −1}, with a detection limit of 2.6 × 10{sup 2} cells mL{sup −1}. The ECL biosensor was also applied to detect prostate specific antigen with a detection limit of 0.1 ng mL{sup −1}. The high selectivity of the biosensor was demonstrated in comparison with that of a lectin-based biosensor. The strategy developed in this study may be a promising approach and could be extended to the design of ECL biosensors for highly sensitive and selective detection of other cancer-related cells or cancer biomarkers using different probes.

  8. Positron Emission Tomography Imaging of Tumor Angiogenesis with a 61/64Cu-Labeled F(ab')2 Antibody Fragment

    Science.gov (United States)

    Hong, Hao; Zhang, Yin; Orbay, Hakan; Valdovinos, Hector F.; Nayak, Tapas R.; Bean, Jero; Theuer, Charles P.; Barnhart, Todd E.; Cai, Weibo

    2013-01-01

    The objective of this study was to characterize the in vitro and in vivo properties of the F(ab')2 fragment of TRC105, a human/murine chimeric IgG1 monoclonal antibody that binds with high avidity to human and murine CD105 (i.e. endoglin), and investigate its potential for positron emission tomography (PET) imaging of tumor angiogenesis after 61/64Cu-labeling. TRC105-F(ab')2 of high purity was produced by pepsin digestion of TRC105, which was confirmed by SDS-PAGE, HPLC analysis, and mass spectrometry. 61/64Cu-labeling of NOTA-TRC105-F(ab')2 (NOTA denotes 1,4,7-triazacyclononane-1,4,7-triacetic acid) was achieved with yields of > 75% (specific activity: ~115 GBq/μmol). PET imaging revealed rapid tumor uptake of 64Cu-NOTA TRC105-F(ab')2 in the 4T1 murine breast cancer model (5.8 ± 0.8, 7.6 ± 0.6, 5.6 ± 0.4, 5.0 ± 0.6, and 3.8 ± 0.7 %ID/g at 0.5, 3, 16, 24, and 48 h post-injection respectively; n = 4). Since tumor uptake peaked at 3 h post-injection, 61Cu-NOTA-TRC105-F(ab')2 also gave good tumor contrast at 3 and 8 h post-injection. CD105 specificity of the tracers was confirmed by blocking studies and histopathology. In conclusion, the use of a F(ab')2 fragment led to more rapid tumor uptake (which peaked at 3 h post-injection) than radiolabeled intact antibody (which often peaked after 24 h post-injection), which may allow for same day immunoPET imaging in future clinical studies. PMID:23316869

  9. Positron emission tomography imaging of tumor angiogenesis with a (61/64)Cu-labeled F(ab')(2) antibody fragment.

    Science.gov (United States)

    Hong, Hao; Zhang, Yin; Orbay, Hakan; Valdovinos, Hector F; Nayak, Tapas R; Bean, Jero; Theuer, Charles P; Barnhart, Todd E; Cai, Weibo

    2013-02-01

    The objective of this study was to characterize the in vitro and in vivo properties of the F(ab')(2) fragment of TRC105, a human/murine chimeric IgG1 monoclonal antibody that binds with high avidity to human and murine CD105 (i.e., endoglin), and investigate its potential for positron emission tomography (PET) imaging of tumor angiogenesis after (61/64)Cu-labeling. TRC105-F(ab')(2) of high purity was produced by pepsin digestion of TRC105, which was confirmed by SDS-PAGE, HPLC analysis, and mass spectrometry. (61/64)Cu-labeling of NOTA-TRC105-F(ab')(2) (NOTA denotes 1,4,7-triazacyclononane-1,4,7-triacetic acid) was achieved with yields of >75% (specific activity: ∼115 GBq/μmol). PET imaging revealed rapid tumor uptake of (64)Cu-NOTA-TRC105-F(ab')(2) in the 4T1 murine breast cancer model (5.8 ± 0.8, 7.6 ± 0.6, 5.6 ± 0.4, 5.0 ± 0.6, and 3.8 ± 0.7% ID/g at 0.5, 3, 16, 24, and 48 h postinjection respectively; n = 4). Since tumor uptake peaked at 3 h postinjection, (61)Cu-NOTA-TRC105-F(ab')(2) also gave good tumor contrast at 3 and 8 h postinjection. CD105 specificity of the tracers was confirmed by blocking studies and histopathology. In conclusion, the use of a F(ab')(2) fragment led to more rapid tumor uptake (which peaked at 3 h postinjection) than radiolabeled intact antibody (which often peaked after 24 h postinjection), which may allow for same day immunoPET imaging in future clinical studies. PMID:23316869

  10. Electrogenerated chemiluminescence biosensing for the detection of prostate PC-3 cancer cells incorporating antibody as capture probe and ruthenium complex-labelled wheat germ agglutinin as signal probe

    International Nuclear Information System (INIS)

    Highlights: • A novel biosensor was developed for the detection of prostate cancer cells. • The selectivity of the biosensor was improved using antibody as capture probe. • The biosensor showed the low extremely detection limit of 2.6 × 102 cells mL−1. • The ruthenium complex-labelled WGA can be transported in the cell vesicles. - Abstract: A highly selective and sensitive electrogenerated chemiluminescence (ECL) biosensor for the detection of prostate PC-3 cancer cells was designed using a prostate specific antibody as a capture probe and ruthenium complex-labelled wheat germ agglutinin as a signal probe. The ECL biosensor was fabricated by covalently immobilising the capture probe on a graphene oxide-coated glassy carbon electrode. Target PC-3 cells were selectively captured on the surface of the biosensor, and then, the signal probe was bound with the captured PC-3 cells to form a sandwich. In the presence of tripropylamine, the ECL intensity of the sandwich biosensor was logarithmically directly proportion to the concentration of PC-3 cells over a range from 7.0 × 102 to 3.0 × 104 cells mL−1, with a detection limit of 2.6 × 102 cells mL−1. The ECL biosensor was also applied to detect prostate specific antigen with a detection limit of 0.1 ng mL−1. The high selectivity of the biosensor was demonstrated in comparison with that of a lectin-based biosensor. The strategy developed in this study may be a promising approach and could be extended to the design of ECL biosensors for highly sensitive and selective detection of other cancer-related cells or cancer biomarkers using different probes

  11. Determination of human IgG by solid substrate room temperature phosphorescence immunoassay based on an antibody labeled with nanoparticles containing dibromofluorescein luminescent molecules

    International Nuclear Information System (INIS)

    Luminescent silicon dioxide nano-particles with size of 20 nm, which containing dibromofluorescein (D) were synthesized by sol-gel method (symbolized by D-SiO2).The particles can emit intense and stable room temperature phosphorescence signal on polyamide membrane when Pb(Ac)2 was used as a heavy atom perturber. The λexmax/λemmax was 457/622 nm. Our research indicated that the specific immune reaction between goat-anti-human IgG antibody labeled with D-SiO2 and human IgG could be carried out on polyamide membrane quantitatively, and the phosphorescence intensity of the particle was enhanced after the immunoreactions. Thus a new method of solid substrate room temperature phosphorescence immunoassay (SS-RTP-IA) for the determination of human IgG was established basing on antibody labeled with the D-SiO2 nanoparticles. The linear range of this method was 0.0624-20.0 pg human IgG spot-1 (corresponding concentration: 0.156-50.0 ng ml-1, the sample volume: 0.40 μl spot-1) with a limit of detection (LD) as 0.018 pg spot-1, and the regression equation of working curve was ΔIp = 7.201 mIgG (pg spot-1) + 82.57. Samples containing 0.156 and 50.0 ng ml-1 of IgG were measured repeatedly for 11 times and R.S.D.s were 4.1 and 3.4%, respectively. Results showed that this method had the merits as sensitive, accurate and precise

  12. Determination of human IgG by solid substrate room temperature phosphorescence immunoassay based on an antibody labeled with nanoparticles containing Rhodamine 6G luminescent molecules

    Science.gov (United States)

    Jia-Ming, Liu; hui, Zhu Guo; Aihong, Wu; Pingping, Li; Huanhuan, Xu; Li, Long-Di; Liu, Zhen-bo

    2005-03-01

    Luminescent silicon dioxide nanoparticles (R-SiO 2) with size of 50 nm containing Rhodamine 6G (R) were synthesized by sol-gel method. In the presence of Pb(Ac) 2 as a heavy atom perturber, the particle can emit intense and stable room temperature phosphorescence signal of R, respectively, on polyamide membrane, with the λexmax/λemmax=470/635 nm for R. Our research indicates that the specific immune reaction between goat-anti-human IgG antibody labeled with R-SiO 2 and human IgG can be carried on polyamide membrane quantitatively, and the phosphorescence intensity was enhanced after the immunoreactions. Thus, a new method of solid substrate room temperature phosphorescence immunoassay (SS-RTP-IA) for the determination of human IgG was established basing on antibody labeled with the nanoparticles containing binary luminescent molecules. The linear range of this method is 0.0624-20.0 pg spot -1 of human IgG (corresponding concentration, 0.156-50.0 ng mL -1; sample volume, 0.40 μL spot -1). The regression equations of working curves are Δ Ip = 88.16. + 16.79m IgG (pg spot -1) (485/646 nm, r = 0.9997). Detection limits calculated by 3Sb/k are 0.017 pg spot -1. For samples containing 0.156 and 50.0 ng mL -1 of IgG, we measured repeatedly for 11 times, RSDs are 3.9 and 2.8%, respectively. This method is sensitive, accurate and of high precision.

  13. Pharmacokinetic properties of a 67Ga-labeled anti-TNF VHH single domain antibody containing a bacterial albumin-binding domain (Zag)

    International Nuclear Information System (INIS)

    Full text of publication follows. Small domain antibodies (SDA's) present high potential for both molecular in vivo imaging and therapy [Refs.1,2]. Owing to the low molecular weight they are rapidly cleared from circulation, and a strategy to extend their half-lives is needed for therapeutic applications. We have selected a bacterial albumin-binding domain (Zag) fused to an anti-TNF VHH SDA to delay blood clearance [Ref.3]. To assess whether the fusion of Zag to the SDA will increase its blood half-life, we have labeled the fusion protein (VHH-Zag) and the antibody alone (VHH) with 67Ga via a 1,4,7- triazacyclononane-1,4,7-triacetic acid (NOTA) derivative and performed biodistribution studies in CD-1 mice. The results have shown that the ZAG domain affected the pharmacokinetics of VHH, with impressive differences in blood clearance (0.028 ± 0.004 versus 1.7 ± 0.8 % ID/g) and total excretion (97.8 ± 0.6 versus 25.5 ± 2.1 % ID) for 67Ga-NOTA-VHH and 67Ga-NOTA-VHHZAG, respectively, at 24 h p.i. The immunoreactivity of the SDA is preserved upon conjugation to NOTA. References: [1] Kontermann, R. E., Biodrugs 2009, 23, 93; [2] Romer, T. et al., Curr. Opin. Immunol. 2011, 22, 882; [3] Jonsson, H. et al., Infect. Immun. 1995, 63, 2968. (authors)

  14. A Highly Selective and Sensitive Fluorescence Detection Method of Glyphosate Based on an Immune Reaction Strategy of Carbon Dot Labeled Antibody and Antigen Magnetic Beads.

    Science.gov (United States)

    Wang, Duo; Lin, Bixia; Cao, Yujuan; Guo, Manli; Yu, Ying

    2016-08-01

    A sensitive fluorescence detection method for glyphosate (GLY) was established based on immune reaction. First, carbon dot labeled antibodies (lgG-CDs) which were able to specifically identify glyphosate were prepared with the environmentally friendly carbon dots (CDs) and glyphosate antibody (lgG). lgG-CDs could be used to in situ visualize the distribution of glyphosate in plant tissues. In order to eliminate the effects of excess lgG-CDs on the determination of GLY, antigen magnetic beads Fe3O4-GLY based on magnetic nanoparticles Fe3O4 and glyphosate were constructed and utilized to couple with the excess lgG-CDs. After magnetic separation to remove antigen magnetic beads, there was a linear relationship between the fluorescence intensity of lgG-CDs and the logarithmic concentration of glyphosate in the range of 0.01-80 μg/mL with a detection limit of 8 ng/mL. The method was used for the detection of glyphosate in Pearl River water, tea, and soil samples with satisfactory recovery ratio between 87.4% and 103.7%. PMID:27403652

  15. Initial experience with locoregional radioimmunotherapy using 131I-labelled monoclonal antibodies against tenascin (BC-4) for treatment of glioma (WHO III and IV)

    International Nuclear Information System (INIS)

    Aim: None of the established treatments (surgery, radiotherapy, chemotherapy) for malignant glioma has improved its very poor prognosis. Adjuvant locoregional radioimmunotherapy (RIT) represents a new therapeutic approach. We present our initial experience with this therapeutic tool with respect to adverse effects, biokinetics and clinical follow-up. Methods: Following surgery and radiotherapy, 12 patients with glioma (4, WHO stage III; 8, WHO stage IV) underwent 1-5 RIT-cycles (average dose 1100 MBq 131labelled monoclonal BC-4 antibodies) at six week intervals. Follow-up included serial FDG-PET and MRI investigations. Evaluation of biokinetics included whole body scans, together with analysis of blood, urine and fluid from the tumor cavity. Results: Following RIT, four patients experienced temporary seizures, which, in one case, were associated with temporary aphasia. Eight patients developed HAMA (human anti-mouse anti-bodies) during follow-up. Mean biologic half-life of the radiopharmaceutical in the resection cavity was 3.9 d (range: 1.0-10.2 d) and remained stable intraindividually during further RIT-cycles. The antibody/radionuclide conjugate remain stable in the tumor cavity for at least 5 d. Median survival presently stands at 18.5 months compared to 9.7 months in a historical patient group (n=89) undergoing conventional therapeutic strategies. Five patients show no signs of recurrence. In three patients with post-surgical evidence of residual tumor, one patient showed partial remission, one stable disease, and one progressive disease during RIT. Four patients without evidence of residual tumor mass at the beginning of RIT developed recurrence during therapy. Conclusions: Initial experience demonstrates that locoregional RIT is a well tolerated treatment modality that may represent a promising new approach in the management of patients with malignant glioma. Advantages of local application include passage of the blood-brain barrier, high concentration of

  16. Detection of anthrax protective antigen (PA) using europium labeled anti-PA monoclonal antibody and time-resolved fluorescence.

    Science.gov (United States)

    Stoddard, Robyn A; Quinn, Conrad P; Schiffer, Jarad M; Boyer, Anne E; Goldstein, Jason; Bagarozzi, Dennis A; Soroka, Stephen D; Dauphin, Leslie A; Hoffmaster, Alex R

    2014-06-01

    Inhalation anthrax is a rare but acute infectious disease following adsorption of Bacillus anthracis spores through the lungs. The disease has a high fatality rate if untreated, but early and correct diagnosis has a significant impact on case patient recovery. The early symptoms of inhalation anthrax are, however, non-specific and current anthrax diagnostics are primarily dependent upon culture and confirmatory real-time PCR. Consequently, there may be a significant delay in diagnosis and targeted treatment. Rapid, culture-independent diagnostic tests are therefore needed, particularly in the context of a large scale emergency response. The aim of this study was to evaluate the ability of monoclonal antibodies to detect anthrax toxin proteins that are secreted early in the course of B. anthracis infection using a time-resolved fluorescence (TRF) immunoassay. We selected monoclonal antibodies that could detect protective antigen (PA), as PA83 and also PA63 and LF in the lethal toxin complex. The assay reliable detection limit (RDL) was 6.63×10(-6)μM (0.551ng/ml) for PA83 and 2.51×10(-5)μM (1.58ng/ml) for PA63. Despite variable precision and accuracy of the assay, PA was detected in 9 out of 10 sera samples from anthrax confirmed case patients with cutaneous (n=7), inhalation (n=2), and gastrointestinal (n=1) disease. Anthrax Immune Globulin (AIG), which has been used in treatment of clinical anthrax, interfered with detection of PA. This study demonstrates a culture-independent method of diagnosing anthrax through the use of monoclonal antibodies to detect PA and LF in the lethal toxin complex. PMID:24857756

  17. Improved flow cytometric identification of myelopoiesis by the simultaneous labelling with CD13, CD14 and CD66 monoclonal antibodies

    DEFF Research Database (Denmark)

    Bonde, J; Meyer, K; Broe, M K; Hokland, M; Turley, H; Hokland, P

    1996-01-01

    The aim of the present study was to increase our knowledge of myelopoiesis evaluated by flow cytometry. We therefore designed a triple-marker assay employing monoclonal antibodies against the CD13 (immature), the CD14 (monocytic), and the CD66 (mature myeloid) antigens using three......-colour immunofluorescence. In normal donor bone marrow the assay enables simultaneous identification of immature (CD13+, CD14-, CD66-), intermediate (CD13+, myelopoietic differentiation stages through the exclusion of CD14+ monocytic cells. In the diagnosis and longitudinal follow-up of AML patients the assay was of value...

  18. Radioimmunotherapy for pancreatic carcinoma using 131I-labeled monoclonal antibody Nd2 in xenografted nude mice

    International Nuclear Information System (INIS)

    We investigated the biodistribution, radiolocalization, and radioimmunotherapeutic potential of 131I-labeled Nd2 in athymic nude mice bearing human pancreatic carcinoma xenografts. 131I-Nd2 was accumulated at high levels in the tumor, in contrast to blood, liver, spleen, and other normal organs. The tumor was clearly delineated in scintigraphs. The volumes of tumors of mice injected with 7.4 MBq of 131I-Nd2 were 80% less than those of tumors before injection of radiolabeled Nd2. Fibrous or vacuolar degeneration was seen in histological sections of tumors of 7-week-treated mice. The growth of tumors in mice treated with misonidazole, a hypoxic cell radiosensitizer, and then injected twice with 3.7 MBq of 131I-Nd2 was suppressed over 7 weeks. Neither leucocytopenia nor thrombocytopenia was severe after injection of radiolabeled Nd2. Thus 131I-labeled Nd2 may have clinical application in the radioimmunotherapy of pancreatic cancer. (author)

  19. Second antibody clearance of /sup 131/I-labeled anti-carcinoembryonic antigen for improved tumor imaging

    International Nuclear Information System (INIS)

    The authors have investigated the use of a second antibody (SA) directed against the radiolabeled primary anti-tumor antibody (PA) to enhance the clearance rate of the PA from the circulation and nontarget tissues. Administration of 50 or 250 μg of anti-goat IgG (SA) hr after the administration of 10 μg of /sup 131/I-goat anti-carcinoembryonic antigen antibody (PA) to hamsters bearing human colonic tumor xenografts resulted in a 5-fold reduction in the level of circulating PA after 4 hr in comparison to the control group only given /sup 131/I-PA. The percentage of PA in the blood decreased rapidly over 72 hr in animals given 250 μg of the SA, but at 50 μg of SA the level of activity in the blood after 24 hr was similar to the control. Tumor accretion was identical after 4 hr, but after 24 hr the animals given 250 μg of SA had 2-3 fold less PA in the tumor than either the control group or the 50 μg dose of SA. Tumor/nontumor ratios for all major organs but the spleen improved 6-8 fold within 48 hr after injection of 250 μg of the SA with tumor/blood ratios as high as 40:1. A SA dose of 50 μg resulted in a significantly higher tumor/blood ratio after only 4 hr; tumor/nontumor ratios at later times were similar to the control group. Tumors located in the hind legs were visible in all groups by imaging 24 hr after injection of the SA, but only the 250 μg dose of SA showed a significant reduction in total body activity. These results suggest that the SA approach may be used to reduce the total background radioactivity while maintaining tumor accretion of /sup 131/I-PA to allow for selective tumor imaging

  20. High contrast tumor imaging with radio-labeled antibody Fab fragments tailored for optimized pharmacokinetics via PASylation

    Science.gov (United States)

    Mendler, Claudia T; Friedrich, Lars; Laitinen, Iina; Schlapschy, Martin; Schwaiger, Markus; Wester, Hans-Jürgen; Skerra, Arne

    2015-01-01

    Although antigen-binding fragments (Fabs) of antibodies constitute established tracers for in vivo radiodiagnostics, their functionality is hampered by a very short circulation half-life. PASylation, the genetic fusion with a long, conformationally disordered amino acid chain comprising Pro, Ala and Ser, provides a convenient way to expand protein size and, consequently, retard renal filtration. Humanized αHER2 and αCD20 Fabs were systematically fused with 100 to 600 PAS residues and produced in E. coli. Cytofluorimetric titration analysis on tumor cell lines confirmed that antigen-binding activities of the parental antibodies were retained. The radio-iodinated PASylated Fabs were studied by positron emission tomography (PET) imaging and biodistribution analysis in mouse tumor xenograft models. While the unmodified αHER2 and αCD20 Fabs showed weak tumor uptake (0.8% and 0.2% ID/g, respectively; 24 h p.i.) tumor-associated radioactivity was boosted with increasing PAS length (up to 9 and 26-fold, respectively), approaching an optimum for Fab-PAS400. Remarkably, 6- and 5-fold higher tumor-to-blood ratios compared with the unmodified Fabs were measured in the biodistribution analysis (48 h p.i.) for αHER2 Fab-PAS100 and Fab-PAS200, respectively. These findings were confirmed by PET studies, showing high imaging contrast in line with tumor-to-blood ratios of 12.2 and 5.7 (24 h p.i.) for αHER2 Fab-PAS100 and Fab-PAS200. Even stronger tumor signals were obtained with the corresponding αCD20 Fabs, both in PET imaging and biodistribution analysis, with an uptake of 2.8% ID/g for Fab-PAS100 vs. 0.24% ID/g for the unmodified Fab. Hence, by engineering Fabs via PASylation, plasma half-life can be tailored to significantly improve tracer uptake and tumor contrast, thus optimally matching reagent/target interactions. PMID:25484039

  1. Imaging and Selective Elimination of Glioblastoma Stem Cells with Theranostic Near-Infrared-Labeled CD133-Specific Antibodies

    Science.gov (United States)

    Jing, Hua; Weidensteiner, Claudia; Reichardt, Wilfried; Gaedicke, Simone; Zhu, Xuekai; Grosu, Anca-Ligia; Kobayashi, Hisataka; Niedermann, Gabriele

    2016-01-01

    Near-infrared photoimmunotherapy (NIR-PIT), which employs monoclonal antibody (mAb)-phototoxic phthalocyanine dye IR700 conjugates, permits the specific, image-guided and spatiotemporally controlled elimination of tumor cells. Here, we report the highly efficient NIR-PIT of human tumor xenografts initiated from patient-derived cancer stem cells (CSCs). Using glioblastoma stem cells (GBM-SCs) expressing the prototypic CSC marker AC133/CD133, we also demonstrate here for the first time that NIR-PIT is highly effective against brain tumors. The intravenously injected theranostic AC133 mAb conjugate enabled the non-invasive detection of orthotopic gliomas by NIR fluorescence imaging, and reached AC133+ GBM-SCs at the invasive tumor front. AC133-targeted NIR-PIT induced the rapid cell death of AC133+ GBM-SCs and thereby strong shrinkage of both subcutaneous and invasively growing brain tumors. A single round of NIR-PIT extended the overall survival of mice with established orthotopic gliomas by more than a factor of two, even though the harmless NIR light was applied through the intact skull. Humanised versions of this theranostic agent may facilitate intraoperative imaging and histopathological evaluation of tumor borders and enable the highly specific and efficient eradication of CSCs.

  2. Biotin radioligand assay with an 125I-labeled biotin derivative, avidin, and avidin double-antibody reagents

    International Nuclear Information System (INIS)

    We describe a new radioligand assay for determining biotin in biological fluids by using a mixture of N-[beta-(4-OH-3-125I-phenyl)ethyl]- and N-[beta-(4-OH-3,5-di-125I-phenyl)ethyl]biotinamides as radiotracer, avidin as a binding protein, and an avidin double-antibody as a separation reagent. The radiotracer is synthesized by coupling (at pH 8.5, 20-22 degrees C, 90 min) N-hydroxysuccinimidobiotin to radioiodinated tyramine. The assay curve is linear and the assay itself is sensitive (less than 10 ng/L), reproducible (intra- and interassay CVs 4.1% and 7.0%, respectively), and allows the simultaneous handling of more than 100 samples in less than 4 h. Serum samples from apparently normal subjects contained 100-840 ng of biotin per liter (mean 340 ng/L). Pregnant women had low concentrations of biotin (100-300 ng/L) in their serum. Patients undergoing chronic hemodialysis treatment showed high concentrations (0.5-3.0 micrograms/L), which may be ascribable to the inability of avidin, which was used as the assay binding protein, to distinguish biotin from biotinyl derivatives with an intact ureido ring

  3. An experimental study on labeling monoclonal antibody 4E5 with 131I and the lethal effects of 131I-4E5 against B cell lymphoma

    International Nuclear Information System (INIS)

    Objective: To label the monoclonal antibody 4E5 with 131I and to evaluate the lethal effects of 131I-4E5 against B cell lymphoma. Methods: 4E5 was radiolabeled with 131I using the Iodogen method at room temperature. The labeling efficiency and radiochemical purity was measured with trichloroacetic acid (TCA) precipitation, and the immune activity and stability of 131I-4E5 was analyzed. The lethal effects of 131I-4E5 and 4E5 against Raji cells were evaluated by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-dipheny-lte-trazolium bromide (MTT) assay. Analysis of variance and t-test were used for data analysis with SPSS 13.0. Results: The labeling rate of 131I-4E5 was (78.3±2.4)%, and the radiochemical purity was (95.7±1.8)%. Its specific activity and radioactive concentration were 0.58 MBq/μg and 3.90 × 1010 Bq/L, respectively. The radiochemical purity of 131I-4E5 mixed with serum and PBS was over 90% after three days. The maximum specific binding efficiency of 131I-4E5 with Raji cells was (36.06±2.63)%. 131I-4E5 exhibited a dose-dependent cytotoxicity against Raji cells. The lethal effect of the high dose group was significantly stronger than that of the low dose group. When the radioactive concentrations were 1.48 × 1010, 7.40 × 109, 3.70 × 109, 1.85 × 109 and 9.25 × 108 Bq/L, the cell inhibition ratios were (52.98±5.19)%, (46.29±2.80)%, (41.05±4.83)%, (33.68±3.79)% and (17.89±2.78)%, respectively (F=33.882, P<0.001). In the 4E5 group, when concentrations of 4E5 were 20.0, 10.0, 5.0, 2.5 and 1.25 mg/L, the cell inhibition ratios were (32.98±3.99)%,(30.88±3.98)%, (27.14±2.05)%, (20.35±4.38)% and (8.42±1.05)%, respectively. Accordingly,significantly higher growth inhibition rates for Raji cells than 4E5 at all antibody concentrations were tested (t=5.290, 5.489, 4.596, 3.986 and 5.515, all P<0.05). Conclusions: The labeling efficiency and radiochemical purity of 131I-4E5 using Iodogen method is high,and the in vitro stability of 131I-4E5 is optimal. 131I-4E5

  4. European multicenter study on melanoma immunoscintigraphy by means of 99mTc-labelled monoclonal antibody fragments

    International Nuclear Information System (INIS)

    A total of 493 melanoma patients were investigated by 20 European nuclear medicine departments by means of the same 99mTc-labelled immunoradiopharmaceutical and the same immunoscintigraphy (ISG) protocol. (i) No chemical or clinical toxicity was detected during or following the studies. (ii) Positive results were obtained in 287/363 (79%) patients (321 carrying known lesions and 42 carrying previously occult lesions): In 231 (80%) of them, 402/402 lesions were imaged; in the remaining 56 ISG-positive patients, 108/204 lesions were imaged; in 76 patients 0/122 lesions were imaged. (iii) The fraction of melanoma lesions visualized by ISG was 510/728 (70.1%); 605 of these lesions were already documented at the time of the study, and 123 were previously occult. (iv) A total of 218 documented melanoma lesions (30%) were not visualized by ISG in 132 patients: About 70% of the ISG-negative lesions were of small size (less than 2 cm diameter). (v) The melanoma nature of 69/123 previously occult lesions was confirmed by clinical criteria and/or additional investigations in follow-up studies. The results obtained in this study are similar to those obtained in the Italian Multicenter Study which had previously been carried out with 258 melanoma patients. (orig.)

  5. Synthesis and pre-clinical evaluation of an (18)F-labeled single-chain antibody fragment for PET imaging of epithelial ovarian cancer.

    Science.gov (United States)

    Sharma, Sai Kiran; Wuest, Melinda; Way, Jenilee D; Bouvet, Vincent R; Wang, Monica; Wuest, Frank R

    2016-01-01

    Anti-CA125 antibodies have been used in immunoassays to quantify levels of shed antigen in the serum of patients who are under surveillance for epithelial ovarian cancer (EOC). However, there is currently no molecular imaging probe in the clinic for the assessment of CA125 expression in vivo. The present study describes the development of an (18)F-labeled single-chain variable fragment (scFv) for PET imaging of CA125 in preclinical EOC models. Anti-CA125 scFv was derived from MAb-B43.13 by recombinant expression of the fragment in E.coli. Fragment scFv-B43.13 was purified via immobilized metal affinity chromatography and characterized for antigen binding via immuno-staining and flow cytometry. Prosthetic group N-succinimidyl 4-[(18)F]fluorobenzoate ([(18)F]SFB) was used for radiolabeling of scFv-B43.13. Preclinical ovarian cancer models were developed based on ovarian cancer cell lines OVCAR3 (CA125-positive) and SKOV3 (CA125-negative) in NIH-III mice. The radiopharmacological profile of (18)F-labeled scFv-B43.13 ([(18)F]FBz-scFv-B43.13) was studied with PET. [(18)F]FBz-scFv-B43.13 was prepared in radiochemical yields of 3.7 ± 1.8% (n = 5) at an effective specific activity of 3.88 ± 0.76 GBq/µmol (n = 5). The radiotracer demonstrated selective uptake in CA125-positive OVCAR3 cells and virtually no uptake in CA125-negative SKOV3 cells. Standardized uptake values (SUV) of radioactivity uptake in OVCAR3 tumors was 0.5 (n = 3) and 0.3 (n = 2) in SKOV3 tumors after 60 min post injection (p.i.). PMID:27508105

  6. Synthesis and pre-clinical evaluation of an 18F-labeled single-chain antibody fragment for PET imaging of epithelial ovarian cancer

    Science.gov (United States)

    Sharma, Sai Kiran; Wuest, Melinda; Way, Jenilee D; Bouvet, Vincent R; Wang, Monica; Wuest, Frank R

    2016-01-01

    Anti-CA125 antibodies have been used in immunoassays to quantify levels of shed antigen in the serum of patients who are under surveillance for epithelial ovarian cancer (EOC). However, there is currently no molecular imaging probe in the clinic for the assessment of CA125 expression in vivo. The present study describes the development of an 18F-labeled single-chain variable fragment (scFv) for PET imaging of CA125 in preclinical EOC models. Anti-CA125 scFv was derived from MAb-B43.13 by recombinant expression of the fragment in E.coli. Fragment scFv-B43.13 was purified via immobilized metal affinity chromatography and characterized for antigen binding via immuno-staining and flow cytometry. Prosthetic group N-succinimidyl 4-[18F]fluorobenzoate ([18F]SFB) was used for radiolabeling of scFv-B43.13. Preclinical ovarian cancer models were developed based on ovarian cancer cell lines OVCAR3 (CA125-positive) and SKOV3 (CA125-negative) in NIH-III mice. The radiopharmacological profile of 18F-labeled scFv-B43.13 ([18F]FBz-scFv-B43.13) was studied with PET. [18F]FBz-scFv-B43.13 was prepared in radiochemical yields of 3.7 ± 1.8% (n = 5) at an effective specific activity of 3.88 ± 0.76 GBq/µmol (n = 5). The radiotracer demonstrated selective uptake in CA125-positive OVCAR3 cells and virtually no uptake in CA125-negative SKOV3 cells. Standardized uptake values (SUV) of radioactivity uptake in OVCAR3 tumors was 0.5 (n = 3) and 0.3 (n = 2) in SKOV3 tumors after 60 min post injection (p.i.). PMID:27508105

  7. Detection of pulmonary embolism with 99mTc-Labeled F(ab)2 fragment of anti-P-selectin monoclonal antibody in dogs

    International Nuclear Information System (INIS)

    Pulmonary embolism is a common and potentially life-threatening condition, and its correct diagnosis is highly desirable before anticoagulant therapy is initiated. However, the safe and accurate diagnosis of acute pulmonary embolism remains a challenge. Single photon emission computed tomography (SPECT) is a highly sensitive scintigraphic imaging technique. Pulmonary embolism can be detected by SPECT with 99mTc-labeled imaging agents that bind to components present predominantly on thromboemboli. P-selectin is an adhesion glycoprotein that is expressed in platelets and endothelial cells. P-selectin on activated platelets is a suitable biomarker of the active thrombus process. The objective of this study was to evaluate 99mTc-labeled F(ab)2 fragment of anti-P-selectin monoclonal antibody SZ51, 99mTc-SZ51-F(ab)2, for imaging pulmonary embolism in beagle canines. SZ51 was digested to F(ab)2 fragment, named SZ51-F(ab)2, and its specific binding to P-selectin on either human or canine platelets was verified by flow cytometry assay. In each dog, an 18-gauge catheter was inserted into left or right pulmonary artery, and a two-stranded spiral stainless-steel coil (20 mm) was inserted through catheter. At 30 min after coil placement, X-ray angiography was performed to document the pulmonary embolism and the locations of the coil. After intravenous injection of 99mTc-SZ51-F(ab)2, experimental thrombi in dogs could be consistently visualized for 2-3 hours by SPECT. Pulmonary embolism showed higher uptake of 99mTc-SZ51-F(ab)2. The present study suggests that 99mTc-SZ51-F(ab)2 may be a promising agent for detecting pulmonary embolism. (author)

  8. Follow-up of relapsed B-cell lymphoma patients treated with iodine-131-labeled anti-CD20 antibody and autologous stem-cell rescue

    International Nuclear Information System (INIS)

    Radioimmunotherapy (RIT) is a promising treatment approach for B-cell lymphomas. This is our first opportunity to report long-term follow-up data and late toxicities in 29 patients treated with myeloablative doses of iodine-131-anti-CD20 antibody (anti-B1) and autologous stem-cell rescue. PATIENTS AND METHODS: Trace-labeled biodistribution studies first determined the ability to deliver higher absorbed radiation doses to tumor sites than to lung, liver, or kidney at varying amounts of anti-B1 protein (0.35, 1.7, or 7 mg/kg). Twenty- nine patients received therapeutic infusions of single-agent (131)I- anti-B1, given at the protein dose found optimal in the biodistribution study, labeled with amounts of (131)I (280 to 785 mCi[10.4 to 29.0 GBq]) calculated to deliver specific absorbed radiation doses to the normal organs, followed by autologous stem-cell support. RESULTS: Major responses occurred in 25 patients (86%), with 23 complete responses (CRs; 79%). The nonhematopoietic do se-limiting toxicity was reversible cardiopulmonary insufficiency, which occurred in two patients at RIT doses that delivered > or = 27 Gy to the lungs. With a median follow-up time of 42 months, the estimated overall and progression-free survival rates are 68% and 42%, respectively. Currently, 14 of 29 patients remain in unmaintained remissions that range from 27+ to 87+ months after RIT. Late toxicities have been uncommon except for elevated thyroid-stimulating hormone (TSH) levels found in approximately 60% of the subjects. Two patients developed second malignancies, but none have developed myelodysplasia (MDS). CONCLUSION: Myeloablative (131)I-anti- B1 RIT is relatively well tolerated when given with autologous stem- cell support and often results in prolonged remission durations with few late toxicities

  9. Quantitative PET of EGFR expression in xenograft-bearing mice using {sup 64}Cu-labeled cetuximab, a chimeric anti-EGFR monoclonal antibody

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Weibo; Chen, Kai; He, Lina; Cao, Qizhen; Chen, Xiaoyuan [Stanford University School of Medicine, The Molecular Imaging Program at Stanford (MIPS), Department of Radiology and Bio-X Program, Stanford, CA (United States); Koong, Albert [Stanford University School of Medicine, Department of Radiation Oncology, Stanford, CA (United States)

    2007-06-15

    Cetuximab, a chimeric monoclonal antibody targeting epidermal growth factor receptor (EGFR) on the surface of cancer cells, was approved by the FDA to treat patients with metastatic colorectal cancer. It is currently also in advanced-stage development for the treatment of several other solid tumors. Here we report for the first time the quantitative positron emission tomography (PET) imaging of EGFR expression in xenograft-bearing mice using {sup 64}Cu-labeled cetuximab. We conjugated cetuximab with macrocyclic chelating agent 1,4,7,10-tetraazadodecane-N,N',N'',N'''-tetraacetic acid (DOTA), labeled with {sup 64}Cu, and tested the resulting {sup 64}Cu-DOTA-cetuximab in seven xenograft tumor models. The tracer uptake measured by PET was correlated with the EGFR expression quantified by western blotting. The estimated human dosimetry based on the PET data in Sprague-Dawley rats was also calculated. MicroPET imaging showed that {sup 64}Cu-DOTA-cetuximab had increasing tumor activity accumulation over time in EGFR-positive tumors but relatively low uptake in EGFR-negative tumors at all times examined (<5%ID/g). There was a good correlation (R {sup 2} = 0.80) between the tracer uptake (measured by PET) and the EGFR expression level (measured by western blotting). Human dosimetry estimation indicated that the tracer may be safely administered to human patients for tumor diagnosis, with the dose-limiting organ being the liver. The success of EGFR-positive tumor imaging using {sup 64}Cu-DOTA-cetuximab can be translated into the clinic to characterize the pharmacokinetics, to select the right population of patients for EGFR-targeted therapy, to monitor the therapeutic efficacy of anti-EGFR treatment, and to optimize the dosage of either cetuximab alone or cetuximab in combination with other therapeutic agents. (orig.)

  10. Simultaneous radiotherapy and radioimmunotherapy of malignant gliomas with anti-EGFR antibody labelled with iodine 125. Preliminary results

    International Nuclear Information System (INIS)

    In this paper we present the preliminary results of a prospective trial of the efficacy of simultaneous radiotherapy and anti-EGFR 125I radioimmunotherapy of malignant gliomas with 2 years' total survival as the end-point, raising the question whether anti-EGFR 125I radioimmunotherapy influences the disease-free survival in these patients. Patients with anaplastic astrocytoma or primary glioblastoma were previously treated by a macroscopically radical neurosurgical approach and randomized either to radiotherapy + radioimmunotherapy arm or treated by radiotherapy alone. Seven patients were included in the group with radioimmunotherapy, among them five with GBM and two with AA, and five patients in the control arm. Patients were irradiated to 60 Gy using three-dimensional conformal noncoplanar techniques. Anti-EGFR 125I monoclonal antibody 425 radioimmunotherapy (50 mCi/course) was started during 4. week of radiotherapy and was repeated three times in one week intervals. Time of follow-up ranges between 2 and 10 months in the anti-EGFR 125I radioimmunotherapy arm and 4 and 9 months in the control arm. Recurrence was diagnosed in all patients in the EGFR 125I group with a lethal outcome in two of them and in 4 patients in the control group. Median time to recurrence was 2 and 5 months respectively. Taking into account early recurrences observed, we propose to continue the studies on the efficacy of adjuvant anti-EGFR 125I radioimmunotherapy in a selected group of patients in whom the greatest benefit may be expected on the basis of molecular studies, among them EGFR expression investigation. (author)

  11. Effect of chelator conjugation level and injection dose on tumor and organ uptake of 111In-labeled MORAb-009, an anti-mesothelin antibody

    International Nuclear Information System (INIS)

    Introduction: Radiolabeling of a monoclonal antibody (mAb) with a metallic radionuclide requires the conjugation of a bifunctional chelator to the mAb. The conjugation, however, can alter the physical and immunological properties of the mAb, consequently affecting its tumor-targeting pharmacokinetics. In this study, we investigated the effect of the amount of 2-(p-isothiocyanatobenzyl)-cyclohexyl-diethylenetriamine-pentaacetic acid (CHX-A″) conjugated to MORAb-009, a mAb directed against mesothelin, and the effect of MORAb dose on the biodistribution of 111In-labeled MORAb-009. Methods: We used nude mice bearing the A431/K5 tumor as a mesothelin-positive tumor model and the A431 tumor as a mesothelin-negative control. To find the optimal level of CHX-A″ conjugation, CHX-A″-MORAb-009 conjugates with 2.4, 3.5 and 5.5 CHX-A″ molecules were investigated. To investigate the effect of injected MORAb-009 dose on neutralizing the shed mesothelin in the circulation, biodistribution studies were performed after the intravenous co-injection of 111In-labeled MORAb-009 (2.4 CHX-A″/MORAb-009) with three different doses: 0.2, 2 and 30 μg of MORAb-009. Results: The tumor uptake in A431/K5 tumor was four times higher than that in A431 tumor, indicating that the tumor uptake in A431/K5 was mesothelin mediated. The conjugate with 5.5 CHX-A″ showed a lower isoelectric point (pI) and lower immunoreactivity (IR) than the 2.4 CHX-A″ conjugate. These differences were reflected in the biodistribution of the 111In label. The 111In-labeled MORAb-009 conjugated with 2.4 CHX-A″ produced higher tumor uptake and lower liver and spleen uptakes than the 5.5 CHX-A″ conjugate. The biodistribution studies also revealed that the tumor uptake was significantly affected by the injected MORAb-009 dose and tumor size. The 30-μg dose produced higher tumor uptake than the 0.2- and 2-μg doses, whereas the 30-μg dose produced lower liver and spleen uptakes than the 0.2-μg dose

  12. FG-3019 anti-connective tissue growth factor monoclonal antibody: results of an open-label clinical trial in idiopathic pulmonary fibrosis.

    Science.gov (United States)

    Raghu, Ganesh; Scholand, Mary Beth; de Andrade, João; Lancaster, Lisa; Mageto, Yolanda; Goldin, Jonathan; Brown, Kevin K; Flaherty, Kevin R; Wencel, Mark; Wanger, Jack; Neff, Thomas; Valone, Frank; Stauffer, John; Porter, Seth

    2016-05-01

    FG-3019 is a fully human monoclonal antibody that interferes with the action of connective tissue growth factor, a central mediator in the pathogenesis of fibrosis.This open-label phase 2 trial evaluated the safety and efficacy of two doses of FG-3019 administered by intravenous infusion every 3 weeks for 45 weeks in patients with idiopathic pulmonary fibrosis (IPF). Subjects had a diagnosis of IPF within the prior 5 years defined by either usual interstitial pneumonia (UIP) pattern on a recent high-resolution computed tomography (HRCT) scan, or a possible UIP pattern on HRCT scan and a recent surgical lung biopsy showing UIP pattern. Pulmonary function tests were performed every 12 weeks, and changes in the extent of pulmonary fibrosis were measured by quantitative HRCT scans performed at baseline and every 24 weeks.FG-3019 was safe and well-tolerated in IPF patients participating in the study. Changes in fibrosis were correlated with changes in pulmonary function.Further investigation of FG-3019 in IPF with a placebo-controlled clinical trial is warranted and is underway. PMID:26965296

  13. Radiation dosimetry of 90Y-labeled monoclonal antibody CO17-1A prepared by the site-specific NH2-Bz-DOTA-3A technique

    International Nuclear Information System (INIS)

    90Y-Labeled monoclonal antibody CO17-1A, with specificity for colorectal and pancreatic carcinomas, has shown excellent potential for radioimmunotherapy. A new bifunctional chelate technique, involving site-specific conjugation of 2-p-aminobenzyl-1,4,7,10-tetraazacyclododecanetriacetic acid (NH2-Bz-DOTA-3A) to the oligosaccharide portion of C017-1A, was recently shown to yield 90Y-CO17-1A with greater in vivo stability and tumor specificity than that produced using DTPA- based bifunctional chelate techniques. Radiation absorbed dose estimates for normal structures of reference man and for mouse tumors of various sizes were calculated for 90Y-CO17-1A prepared by the site-specific NH2-Bz-DOTA-3A technique, based on timed tissue distribution studies (6, 24, 48, 72, 120, or 168 hr) in female nude mice bearing SW 948 human colorectal carcinoma xenografts. Radiation absorbed dose estimates for tumor were 50% higher than those obtained in previously reported studies with 90Y-CO-17-1A produced by site-specific conjugation of any acyclic DTPA ligand, whereas radiation doses for normal tissues were similar for the two methods. The absorbed dose to the bone marrow, 2.7 mSv/MBq, will limit the dosage in MBq or mCi of 90Y-CO17-1A that can safely be administered

  14. In vitro and in vivo evaluation of direct rhenium-188-labeled anti-CD52 monoclonal antibody alemtuzumab for radioimmunotherapy of B-cell chronic lymphocytic leukemia

    Energy Technology Data Exchange (ETDEWEB)

    Decker, Mario de [Department of Radiopharmacy, Faculty of Pharmaceutical Sciences, Ghent University, Ghent (Belgium); Department of Nuclear Medicine and Molecular Imaging, University Medical Centre Groningen, Groningen (Netherlands)], E-mail: mario.dedecker@health.wa.gov.au; Bacher, Klaus; Thierens, Hubert [Department of Medical Physics and Radiation Protection, Ghent University, Ghent (Belgium); Slegers, Guido [Department of Medical Imaging of Domestic Animals, Ghent University, Ghent (Belgium); Dierckx, Rudi A. [Department of Nuclear Medicine and Molecular Imaging, University Medical Centre Groningen, Groningen (Netherlands); Vos, Filip de [Department of Radiopharmacy, Faculty of Pharmaceutical Sciences, Ghent University, Ghent (Belgium)

    2008-07-15

    Alemtuzumab (Campath, Berlex) is a humanized IgG1 rat monoclonal antibody directed against the cell surface CD52 antigen, found on lymphocytes and monocytes. It is being developed for the treatment of chronic lymphocytic leukemia (CLL), autoimmune disease and for the prevention of transplant rejection. This study focused on synthesis, quality control, in vitro evaluation and biodistrubution of {sup 188}Re-labeled alemtuzumab for radioimmunotherapy of B-cell CLL. {sup 188}Re-alemtuzumab was synthesized using a direct radiolabeling method. Reduction of the intramolecular disulfide bonds of the antibody was performed with tris-(carboxyethyl)-phosphine (Pierce), using a 1:60 molar excess. Reaction took place at room temperature for 20 min. A PD-10 desalting column was used to purify the reduced antibody from excess phospine. Complexation and transchelation of {sup 188}ReO{sub 4}{sup -} was achieved using sodium gluconate as weak chelator and SnCl{sub 2} as reducing agent. Quality control was done using instant thin-layer chromatography. Binding assays were performed on a CD52-positive cell line (HuT-78). Female NMRI mice were injected intravenously with 20 {mu}g radiolabeled alemtuzumab and killed at preset time intervals for biodistribution studies. Tissues were dissected, weighed and counted for determination of radioactivity. Data were expressed as percentage injected activity per gram of tissue (% IA/g tissue) or as percentage injected activity (% IA). {sup 188}Re-alemtuzumab was prepared achieving high radiochemical yields. Labeling efficiency of more than 95% can be obtained using optimal reaction conditions. {sup 188}Re-alemtuzumab showed good in vitro stability, remaining intact at 24 h after radiolabeling. In mice, {sup 188}Re-alemtuzumab showed high uptake in the blood (25.10{+-}1.36% IA at 1 h p.i.), followed by a biexponential clearance (t{sub 1/2{alpha}}=4.790 h and t{sub 1/2{beta}}=55.45 h). Increased uptake was observed in kidneys and heart (9

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

    Energy Technology Data Exchange (ETDEWEB)

    Akanji, Akinkunmi Ganiyu

    2012-07-01

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

  16. Biodistribution of a 67Ga-labeled anti-TNF VHH single-domain antibody containing a bacterial albumin-binding domain (Zag)

    International Nuclear Information System (INIS)

    Introduction: Small domain antibodies (sdAbs) present high potential for both molecular in vivo imaging and therapy. Owing to the low molecular weight they are rapidly cleared from blood circulation, and new strategies to extend their half-lifes are needed for therapeutic applications. We have selected a bacterial albumin-binding domain (ABD) from protein Zag to be fused to an anti-tumor necrosis factor (TNF) single variable-domain heavy-chain region antibody (VHH) to delay blood clearance, and evaluated the biodistribution profile of the fusion protein. Methods: The anti-TNF VHH and the fusion protein VHH-Zag were conjugated to S-2-(4-isothiocyanatobenzyl)-1,4,7-triazacyclononane-1,4,7-triacetic acid (p-SCN-Bn-NOTA). The anti-TNF and albumin-binding properties of the conjugates NOTA-VHH and NOTA-VHH-Zag were assessed by enzyme-linked immunosorbent assay (ELISA). The radioconjugates 67Ga-NOTA-VHH and 67Ga-NOTA-VHH-Zag were obtained by reaction of 67GaCl3 with the corresponding conjugates at room temperature. Biodistribution studies were performed in healthy female CD-1 mice. Results: The immunoreactivity of the VHH-based proteins is preserved upon conjugation to NOTA as well as after radiometallation. The radiochemical purity of the radioconjugates was higher than 95% as determined by ITLC-SG after purification by gel filtration. The biodistribution studies showed that the Zag domain affected the pharmacokinetic properties of VHH, with impressive differences in blood clearance (0.028 ± 0.004 vs 1.7 ± 0.8 % I.A./g) and total excretion (97.8 ± 0.6 vs 25.5 ± 2.1 % I.A.) for 67Ga-NOTA-VHH and 67Ga-NOTA-VHH-Zag, respectively, at 24 h p.i. Conclusion: The Zag domain prolonged the circulation time of VHH by reducing the blood clearance of the labeled fusion protein 67Ga-NOTA-VHH-Zag. In this way, the anti-TNF VHH in fusion with the Zag ABD presents a higher therapeutic potential than the unmodified VHH

  17. Optimization of biotin labeling of antibodies using mouse IgG and goat anti-mouse IgG-conjugated fluorescent beads and their application as capture probes on protein chip.

    Science.gov (United States)

    Lee, Jin Hyung; Choi, Hong Kyung; Chang, Jeong Ho

    2010-10-31

    This study shows the optimization of biotin labeling to antibodies using mouse IgG. Several parameters of the biotin labeling, including the molar ratio of biotin to antibody, the coupling time and the dialysis time, were studied to optimum conditions. The biotin-tagged mouse IgGs were immobilized on avidin-coated PMMA (Polymethyl Methacrylate) plates via a biotin-avidin linkage. The immobilization of the IgG to the chip was quantified using goat anti-mouse IgG bound fluorescent beads. It was found that the binding of the fluorescent beads saturated when a 10-fold or higher molar ratio of biotin to antibody was used. In biotin coupling time tests, sixty minutes was sufficient for the capture probes to bind to the surface. However, the results from the dialysis experiments showed no difference, indicating that 2 hours was sufficient to remove any unbound biotin. Finally, to prove the universality of this protocol using mouse antibodies, the optimum conditions were successfully applied in sandwich immunoassays designed to detect troponin I (TnI) and N-terminal probrain natriuretic peptide (NT-proBNP). PMID:20804762

  18. Targeting cancer stem cells with an 131I-labeled anti-AC133 monoclonal antibody in human colorectal cancer xenografts

    International Nuclear Information System (INIS)

    Introduction: Cancer stem cells (CSCs) are a subpopulation within a tumor, which possesses the characteristics of self-renewal, differentiation, tumorigenicity, and drug resistance. The aim of this study was to target the colorectal CSC marker CD133 with an131I-labeled specific monoclonal antibody (AC133 mAb) in a nude mouse xenograft model. Methods: Colorectal adenocarcinoma cells (LoVo cell line) were separated into CD133(+) and CD133(−) cells by magnetic activated cell sorting. CD133(+), CD133(−), and unsorted LoVo cells were cultured and then implanted subcutaneously into the lower limbs of nude mice (n = 5). AC133 mAb was labeled with 131I by the iodogen method. Results: The radiolabeled compound, 131I-AC133 mAb, showed high stability, specificity, and immunoactivity in vitro. Obvious accumulation of 131I-AC133 mAb was seen in nude mice bearing xenografts of CD133(+) and unsorted LoVo cells, but no uptake was found in mice bearing CD133(−) xenografts or specifically blocked xenografts. Biodistribution analysis showed that the tumor uptake of 131I-AC133 mAb was 6.97 ± 1.40, 1.35 ± 0.48, 6.12 ± 1.91, and 1.61 ± 0.44% ID/g (n = 4) at day 7 after injection of 131I-AC133 mAb in CD133(+), CD133(−), unsorted LoVo cell and specifically blocked xenografts, respectively. The results of immunofluorescence, autoradiography, and western blotting further verified the specific binding of 131I-AC133 mAb to CD133(+) tumors. Conclusions: This study demonstrates the possibility of targeting CSCs with a radiolabeled AC133 mAb in colorectal cancer xenografts based on in vitro, ex vivo, and in vivo experiments. Our findings suggest a new method for imaging CSCs non-invasively

  19. Evaluation of Efficacy of Radioimmunotherapy with 90Y-Labeled Fully Human Anti-Transferrin Receptor Monoclonal Antibody in Pancreatic Cancer Mouse Models.

    Directory of Open Access Journals (Sweden)

    Aya Sugyo

    Full Text Available Pancreatic cancer is an aggressive tumor and the prognosis remains poor. Therefore, development of more effective therapy is needed. We previously reported that 89Zr-labeled TSP-A01, an antibody against transferrin receptor (TfR, is highly accumulated in a pancreatic cancer xenograft, but not in major normal organs. In the present study, we evaluated the efficacy of radioimmunotherapy (RIT with 90Y-TSP-A01 in pancreatic cancer mouse models.TfR expression in pancreatic cancer cell lines (AsPC-1, BxPC-3, MIAPaCa-2 was evaluated by immunofluorescence staining. 111In-labeled anti-TfR antibodies (TSP-A01, TSP-A02 were evaluated in vitro by cell binding assay with the three cell lines and by competitive inhibition assay with MIAPaCa-2. In vivo biodistribution was evaluated in mice bearing BxPC-3 and MIAPaCa-2 xenografts. Tumor volumes of BxPC-3 and MIAPaCa-2 were sequentially measured after 90Y-TSP-A01 injection and histological analysis of tumors was conducted.MIAPaCa-2 cells showed the highest TfR expression, followed by AsPC-1 and BxPC-3 cells. 111In-TSP-A01 and 111In-TSP-A02 bound specifically to the three cell lines according to TfR expression. The dissociation constants for TSP-A01, DOTA-TSP-A01, TSP-A02, and DOTA-TSP-A02 were 0.22, 0.28, 0.17, and 0.22 nM, respectively. 111In-TSP-A01 was highly accumulated in tumors, especially in MIAPaCa-2, but this was not true of 111In-TSP-A02. The absorbed dose for 90Y-TSP-A01 was estimated to be 8.3 Gy/MBq to BxPC-3 and 12.4 Gy/MBq to MIAPaCa-2. MIAPaCa-2 tumors treated with 3.7 MBq of 90Y-TSP-A01 had almost completely disappeared around 3 weeks after injection and regrowth was not observed. Growth of BxPC-3 tumors was inhibited by 3.7 MBq of 90Y-TSP-A01, but the tumor size was not reduced.90Y-TSP-A01 treatment achieved an almost complete response in MIAPaCa-2 tumors, whereas it merely inhibited the growth of BxPC-3 tumors. 90Y-TSP-A01 is a promising RIT agent for pancreatic cancer, although further

  20. Radioimmunoimaging in malignant melanoma patients with the use of indium-111-labeled antimelanoma monoclonal antibody (ZME-018) to high-molecular-weight antigen

    International Nuclear Information System (INIS)

    Radioimmunolocalization of an 111In-labeled, mouse antimelanoma monoclonal antibody (MAb), ZME-018, was examined in 30 patients with metastatic malignant melanoma. Each patient received a single iv infusion of MAb at concentrations ranging from 0.6 to 40 mg, coupled to 5 mCi 111In by the chelating agent pentetic acid. No toxicity was observed in any patient. Total-body and region of interest scans performed at 4, 24, and 72 hours following MAb administration revealed uptake in 110 of 171 previously diagnosed metastases for a sensitivity of 64%. Nonspecific uptake of radioactivity was consistently observed in the liver and spleen, and less frequently in the bowel, testes, axillae, and bone. Sensitivity of detection increased significantly at doses of MAb above 2.5 mg, with 74% of the lesions imaging at 20 mg/5 mCi compared with 29% at 2.5 mg/5 mCi (P less than .005). Sensitivity actually decreased slightly at the 40-mg dose. There was a significant correlation between tumor uptake of MAb-111In-conjugate and increasing tumor size. Soft tissue lesions, such as skin and lymph node metastases, were imaged to a greater extent (77%) than were visceral metastases (40%). Mean plasma clearance of ZME-018 was prolonged with a half-life of 33.6 hours in patients receiving 40 mg, compared with 17.8 hours in patients given 2.5 mg (P less than .01). Urinary excretion of the isotope averaged 11.4% of the injected dose over 48 hours. Hence radioimmunolocalization of melanoma with 111In-ZME-018 appeared feasible. The sensitivity of the technique varies with MAb dose, specific activity of 111In-MAb conjugate, tumor size, and disease site

  1. Apoptosis and p53 are not involved in the anti-tumor efficacy of 125I-labeled monoclonal antibodies targeting the cell membrane

    International Nuclear Information System (INIS)

    Introduction: 125I-labeled monoclonal antibodies (125I-mAbs) can efficiently treat small solid tumors. Here, we investigated the role of apoptosis, autophagy and mitotic catastrophe in 125I-mAb toxicity in p53−/− and p53+/+ cancer cells. Methods: We exposed p53−/− and p53+/+ HCT116 cells to increasing activities of internalizing (cytoplasmic location) anti-HER1 125I-mAbs, or non-internalizing (cell surface location) anti-CEA 125I-mAbs. For each targeting model we established the relationship between survival and mean nucleus absorbed dose using the MIRD formalism. Results: In both p53−/− and p53+/+ HCT116 cells, anti-CEA 125I-mAbs were more cytotoxic per Gy than anti-HER1 125I-mAbs. Sensitivity to anti-CEA 125I-mAbs was p53-independent, while sensitivity to anti-HER1 125I-mAbs was higher in p53−/− HCT 116 cells, suggesting that they act through different signaling pathways. Apoptosis was only induced in p53+/+ HCT116 cells and could not explain cell membrane radiation sensitivity. Inhibition of autophagy did not modify the cell response to 125I-mAbs. By contrast, mitotic death was similarly induced in both p53−/− and p53+/+ HCT116 cells by the two types of 125I-mAbs. We also showed using medium transfer experiments that γ-H2AX foci were produced in bystander cells. Conclusion: Cell membrane sensitivity to 125I-mAbs is not mediated by apoptosis and is p53-independent. Bystander effects-mediated mitotic death could be involved in the efficacy of 125I-mAbs binding cell surface receptors

  2. Targeting CD45RB alters T cell migration and delays viral clearance.

    Science.gov (United States)

    Lim, Bock; Sutherland, Robyn M; Zhan, Yifan; Deliyannis, Georgia; Brown, Lorena E; Lew, Andrew M

    2006-02-01

    CD45 is a receptor tyrosine phosphatase essential for TCR signaling. One isoform, CD45RB, is down-regulated in memory cells and targeting CD45RB with a specific antibody has been shown to inhibit graft rejection. Its role in immunity to infection, however, has not been tested. Here, we report the effect of anti-CD45RB antibody treatment on the induction of anti-influenza CD8+ T cells and viral clearance. Anti-CD45RB-treated mice had delayed pulmonary viral clearance compared with untreated mice whose infection was completely cleared by day 8 post-infection. In anti-CD45RB-treated mice, the total CD4+ and CD8+ T cell numbers in both the lungs and mediastinal nodes were substantially reduced at days 5 and 8; this effect was less marked for the spleen. CD8+ T cells specific for influenza virus were also reduced compared with the control group in all three organs at day 8. By day 11, when both treated and control groups showed no virus remaining in the lungs, specific CD8+ T cell numbers were at similar low levels. Homing to lymph nodes and lung of dye-labeled T cells was greatly inhibited (by >80%) by anti-CD45RB treatment. This reduced homing corresponded with reduced CD62L and beta1-integrin expression in both uninfected and infected mice. Since CD62L plays a critical role in homing lymphocytes to lymph nodes, and high levels of CD62L and alpha4beta1-integrin are expressed by lymphocytes that home to bronchus-associated lymphoid tissue, we suggest that reduced expression of these molecules is a key explanation for the delay in immune responses. PMID:16361310

  3. The study of labeling with Iodine-131 of monoclonal antibody anti-CD20 used for the treatment of non-Hodgkin lymphoma; Estudo de marcacao com Iodo-131 de anticorpo monoclonal anti-CD20 na terapia de linfoma nao-Hodgkin

    Energy Technology Data Exchange (ETDEWEB)

    Akanji, Akinkunmi Ganiyu

    2006-07-01

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

  4. 抗犬瘟热病毒荧光标记单抗的制备和初步鉴定%Preparation and Preliminary Identification of Fluorescein Labeled Monoclonal Antibody against Canine Distemper Virus

    Institute of Scientific and Technical Information of China (English)

    苏建青; 褚秀玲; 杨松涛; 夏咸柱; 岳妙姝

    2009-01-01

    [Objective] The aim of the present study was to develop a direct immunofluorescence method for the diagnosis of canine distemper (CD) with FITC-conjugated monoclonal antibodies (FITC-McAb). [Method] The McAb against CDV, designated as CE3, was purified with protein G and labeled with FITC through agitation method. After purification and identification, the optimal working concentration of FITC-labeled CE3 was determined. Then 61 clinical samples of suspected canine distemper were detected by direct immunofluorescence assay. [Result] The absorption test, blocking test and specificity test showed that the labeled antibody had high specificity and sensitivity, but didnt have cross reaction with canine parvovirus (CPV), canine parainfluenza virus (CPIV), canine adenovirus (CAV) and rabies virus (RV). The optimal working concentration was 1∶80. The positive rate of clinical suspected samples was 48%. [Conclusion] The direct immunofluorescence assay developed in this study was rapid, specific and convenient, and had great significance for the early diagnosis of canine distemper.

  5. Biological distribution of 131I-labeled anti-nucleus antigen monoclonal antibody chTNT in patients with pulmonary metastases from differentiated thyroid carcinoma

    Institute of Scientific and Technical Information of China (English)

    MA Qingjie; GAO Shi; ZHAO Jie; WEN Qiang; BAI Lin; ZHANG Haoran; ZHAO Guoqing

    2008-01-01

    This work is to study the in vivo biological distribution of 131I-labeled mouse/human chimeric monoclonal antibody (131I-chTNT) in patients with pulmonary metastases from differentiated thyroid carcinoma.Ten patients with differentiated thyroid carcinoma were injected intravenously with a single dose of 131I-chTNT (5 MBq.kg-1 body weight).Radioactivity of blood and urine samples was measured at different time points.The in vivo stability and the metabolic status of 131I-chTNT were detected with supersaturated trichloroacetic acid.Continuous imaging was performed to outline the region of interest (ROD and estimate the intake level on the whole body,major organs and tumor lesions at different time points.The serum time-radioactivity curve of 131I-ehTNT accorded with the two-compartment model after a single intravenous injection:T1/2(h)=65.28±14.83,AUC0-t(MBq.h.mL-1)=8.93±1.32,AUC0-∞(MBq-h-mL-1)=10.58±2.19,and CL(mL.min-1.kg-1)=1635±359.The time-radioactivity percentage curve of 131I-chTNT urine excretion accorded with the one-compartment model after a single intravenous injection:T1/2(h)=99±10,and accumulative (31±9) % radioactivity of the injected dose was excreted in urine in one week.The percentages of serum 131I-ehTNT in radioactive components at 24,48 and 72 h were over 95% and it was still (88±7)% at 168 h.As for chemical composition of radioactive substances in urine,radioactivity in urine samples originated from free 131I by 100%.Radioactivity of 131I-chTNT after intravenous administration was mainly concentrated in the lung and liver,least in the brain.Radioactivity of tumor tissues reached the maximum at 24 h and the tumor/normal tissue (T/N) ratio reached the maximum (1.28~3.83) during 3~7 d.The characteristics of in vivo biological distribution of 131I-chTNT in patients with pulmonary metastases from differentiated thyroid carcinoma are favorable for its therapeutic application for the metastasis tumors.

  6. Synergy of Taxol and radioimmunotherapy with yttrium-90-labeled chimeric L6 antibody: Efficacy and toxicity in breast cancer xenografts

    Science.gov (United States)

    DeNardo, Sally J.; Kukis, David L.; Kroger, Linda A.; O’Donnell, Robert T.; Lamborn, Kathleen R.; Miers, Laird A.; DeNardo, David G.; Meares, Claude F.; DeNardo, Gerald L.

    1997-01-01

    Synergistic multimodality therapy is needed for breast cancer. Breast cancer frequently has p53 mutations that result in cells less likely to undergo apoptosis when exposed to DNA damaging therapies. Taxol (paclitaxel) is more effective in the presence of mutant p53. 90Y-labeled DOTA-peptide-ChL6 (90Y-ChL6, where ChL6 is chimeric L6 antibody and DOTA is 1,4,7,10-tetraazacyclododecane-N,N′,N",N‴-tetraacetic acid) is a novel radioimmunoconjugate for targeting radiation to cancer. It has a stable metal chelator and a peptide linker that can be catabolized by hepatic lysozymes. This study was designed to assess potential synergism between Taxol and 90Y-ChL6 in a highly anaplastic breast cancer model, HBT 3477. There was no tumor response in mice receiving ChL6 or Taxol alone. In mice receiving 90Y-ChL6 alone, 79% (15 of 19) of tumors responded although none were cured. If Taxol was administered 24–72 hours before 90Y-ChL6, again, 79% (23 of 29) of tumors responded but 21% were cured. When Taxol was administered 6 or 24 hours after 90Y-ChL6, 100% (46 of 46) of tumors responded and 48% were cured. Taxol given with 90Y-ChL6 did not substantially increase toxicity. Enhancement of the therapeutic effect when Taxol was added to 90Y-ChL6 therapy for HBT 3477 xenografts was striking. The synergistic therapeutic effect of Taxol with 90Y-ChL6 may relate to the p53 mutant status and BCL2 expression in HBT 3477 cells, observations that increase the likelihood that the results of this study are relevant to therapy for breast cancer in patients. In conclusion, Taxol seemed to be synergistic with 90Y-ChL6 in this human breast cancer model. Up to 50% of these anaplastic breast cancer xenografts were cured by combined modality therapy. PMID:9108094

  7. Biological distribution of 131I-labeled anti-nucleus antigen monoclonal antibody chTNT in patients with pulmonary metastases from differentiated thyroid carcinoma

    International Nuclear Information System (INIS)

    This work is to study the in vivo biological distribution of 131I-labeled mouse/human chimeric monoclonal antibody (131I-chTNT) in patients with pulmonary metastases from differentiated thyroid carcinoma. Ten patients with differentiated thyroid carcinoma were injected intravenously with a single dose of 131I-chTNT (5 MBq·kg-1 body weight). Radioactivity of blood and urine samples was measured at different time points. The in vivo stability and the metabolic status of 131I-chTNT were detected with supersaturated trichloroacetic acid. Continuous imaging was performed to outline the region of interest (ROI) and estimate the intake level on the whole body, major organs and tumor lesions at different time points. The serum time-radioactivity curve of 131I-chTNT accorded with the two-compartment model after a single intravenous injection: T1/2(h)=65.28±14.83, AUC0-t(MBq·h·mL-1)=8.93±1.32, AUC0-∞(MBq·h·mL-1)=10.58±2.19, and CL(mL·min-1·kg-1)=1635±359. The time-radioactivity percentage curve of 131I-chTNT urine excretion accorded with the one-compartment model after a single intravenous injection: T1/2(h)=99±10, and accumulative (31±9)% radioactivity of the injected dose was excreted in urine in one week. The percentages of serum 131I-chTNT in radioactive components at 24, 48 and 72 h were over 95% and it was still (88±7)% at 168 h. As for chemical composition of radioactive substances in urine, radioactivity in urine samples originated from free 131I by 100%. Radioactivity of 131I-chTNT after intravenous administration was mainly concentrated in the lung and liver, least in the brain. Radioactivity of tumor tissues reached the maximum at 24 h and the tumor/normal tissue (T/N) ratio reached the maximum (1.28-3.83) during 3-7 d. The characteristics of in vivo biological distribution of 131I-chTNT in patients with pulmonary metastases from differentiated thyroid carcinoma are favorable for its therapeutic application for the metastasis tumors. (authors)

  8. Study of the viability of technetium-{sup 99m} labeling of whole antimyosin antibody and its fragment: development of radiopharmaceutical for cardiac survey; Estudo da viabilidade da marcacao com tecnecio-99m do anticorpo antimiosina integro e seu fragmento: desenvolvimento de radiofarmaco para avaliacao cardiaca

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Guilherme Luiz de Castro

    2007-07-01

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

  9. Radiolabelled antibodies in imaging

    International Nuclear Information System (INIS)

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

  10. 99mTc direct labeling of a new anti-MUC1 monoclonal antibody, PR81, as a potential agent for imaging of human breast cancer in nuclear medicine

    International Nuclear Information System (INIS)

    Radioimmunoscintigraphy (RIS) is a technique which uses radiolabeled antibodies to visualize tumors, taking advantage of antigens preferentially expressed by malignant tissues. Human epithelial mucin, MUC1, is commonly over expressed in adenocarcinomas including 80% of breast cancers and represents a useful target for RIS. The PR81 is a new murine anti-MUC1 monoclonal antibody that was found to react with the membrane extracts of several human breast cancer tissues and the cell surface of MUC1 positive cell lines. In this study we have developed a direct method for labeling of this MAb with 99mTc which is simple, rapid, efficient and particularly suitable for development of a 'kit'. The quality control of new radiopharmaceutical and immunoscintigraphy studies in BALB/c mice bearing breast tumor xenografts were also performed. (author)

  11. Radiolabeled antibodies as imaging agents

    International Nuclear Information System (INIS)

    The author gives a survey of the progress made on radioimmunodetection. Antibodies may now be more readily used in scintigraphy as a result of the development of labeling methods that apply more suitable radionuclides without significant loss of the antigen-binding activity. Antibodies to tumor-specific or tumor-associated antigens can now be produced in large quantities by monoclonal antibody technology

  12. In vitro characterization of an iodine-125 labeled anti-epidermal growth factor receptor murine monoclonal antibody (MAB-425) in human high grade glioma cells: Binding, uptake, transport and localization

    International Nuclear Information System (INIS)

    The aim of this study was to determine intracellular accumulation and possible nuclear translocation of 125I-labeled murine monoclonal antibody (MAb) 425 in human high grade glioma cells following internalization of this antibody, a prerequisite for the induction of radiotoxic effects. Four human high grade glioma cell lines known to express epidermal growth factor receptor (EGF-R) and a colorectal carcinoma cell line with negligible EGF-R expression were incubated for various time periods with a saturating concentration of 125I-MAb 425. No measurable intranuclear uptake of radioactivity was detected within an incubation period of less than 6 hr. After an incubation of 24-28 hr, only 0.5-2% of the internalized radioactivity was detected in the nuclear fraction. It may be possible to inhibit 125I-MAb 425 degradation with the addition of chloroquine. Overall, the data indicate that the major portion of the 125I-MAb 425 is degraded following internalization. Inhibition of lysosomal activity results in a significant increase in intracellular, but more importantly, intranuclear accumulation of 125I-MAb 425. Since radioactivity is released from the glioma cells following 125I-MAb 425 internalization, discontinuous gel electrophoresis was performed to determine the nature of the released cell products. The cell supernatants were examined at 0, 24 and 48 hr post incubation to determine the nature of any cell-associated radioactivity released from the cell surface or interior. A protein band corresponding to a molecular weight of 167 kDa was detected in all cell supernatants. Parallel electrophoretic gels were processed for autoradiographic studies in order to indicate corresponding radioactive components. In addition, immunostaining by Western blot with peroxidase-labeled goat anti-mouse antibody was performed to confirm the antibody nature of the protein bands

  13. In vitro characterization of an iodine-125 labeled anti-epidermal growth factor receptor murine monoclonal antibody (MAB-425) in human high grade glioma cells: Binding, uptake, transport and localization

    Energy Technology Data Exchange (ETDEWEB)

    Emrich, J.G.

    1993-01-01

    The aim of this study was to determine intracellular accumulation and possible nuclear translocation of [sup 125]I-labeled murine monoclonal antibody (MAb) 425 in human high grade glioma cells following internalization of this antibody, a prerequisite for the induction of radiotoxic effects. Four human high grade glioma cell lines known to express epidermal growth factor receptor (EGF-R) and a colorectal carcinoma cell line with negligible EGF-R expression were incubated for various time periods with a saturating concentration of [sup 125]I-MAb 425. No measurable intranuclear uptake of radioactivity was detected within an incubation period of less than 6 hr. After an incubation of 24-28 hr, only 0.5-2% of the internalized radioactivity was detected in the nuclear fraction. It may be possible to inhibit [sup 125]I-MAb 425 degradation with the addition of chloroquine. Overall, the data indicate that the major portion of the [sup 125]I-MAb 425 is degraded following internalization. Inhibition of lysosomal activity results in a significant increase in intracellular, but more importantly, intranuclear accumulation of [sup 125]I-MAb 425. Since radioactivity is released from the glioma cells following [sup 125]I-MAb 425 internalization, discontinuous gel electrophoresis was performed to determine the nature of the released cell products. The cell supernatants were examined at 0, 24 and 48 hr post incubation to determine the nature of any cell-associated radioactivity released from the cell surface or interior. A protein band corresponding to a molecular weight of 167 kDa was detected in all cell supernatants. Parallel electrophoretic gels were processed for autoradiographic studies in order to indicate corresponding radioactive components. In addition, immunostaining by Western blot with peroxidase-labeled goat anti-mouse antibody was performed to confirm the antibody nature of the protein bands.

  14. γδ T cell-mediated antibody-dependent cellular cytotoxicity with CD19 antibodies assessed by an impedance-based label-free real-time cytotoxicity assay

    OpenAIRE

    Ursula Jördis Eva Seidel; Fabian eVogt; Ludger eGrosse-Hovest; Gundram eJung; Rupert eHandgretinger; Peter eLang

    2014-01-01

    γδ T cells are not MHC restricted, elicit cytotoxicity against various malignancies, are present in early post-transplant phases in novel stem cell transplantation (SCT) strategies and have been shown to mediate antibody-dependent cellular cytotoxicity (ADCC) with monoclonal antibodies (mAbs). These features make γδ T cells promising effector cells for antibody-based immunotherapy in pediatric patients with B-lineage acute lymphoblastic leukemia (ALL). To evaluate combination of human γδ T ce...

  15. γδ T Cell-Mediated Antibody-Dependent Cellular Cytotoxicity with CD19 Antibodies Assessed by an Impedance-Based Label-Free Real-Time Cytotoxicity Assay

    OpenAIRE

    Seidel, Ursula Jördis Eva; Vogt, Fabian; Grosse-Hovest, Ludger; Jung, Gundram; Handgretinger, Rupert; Lang, Peter

    2014-01-01

    γδ T cells are not MHC restricted, elicit cytotoxicity against various malignancies, are present in early post-transplant phases in novel stem cell transplantation strategies and have been shown to mediate antibody-dependent cellular cytotoxicity (ADCC) with monoclonal antibodies (mAbs). These features make γδ T cells promising effector cells for antibody-based immunotherapy in pediatric patients with B-lineage acute lymphoblastic leukemia (ALL). To evaluate combination of human γδ T cells wi...

  16. Experimental investigations with radiolabeled anti-collagen antibody

    International Nuclear Information System (INIS)

    Antibodies to collagen were prepared and labelled with indium 111. Kinetic studies were performed using labelled antibody for up to 48 hours following an injury. These results provide a method to detect injury by radioimmunographic techniques. 5 figs., 3 tabs

  17. Hepatitis A virus antibody

    International Nuclear Information System (INIS)

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

  18. Label-free Fab and Fc affinity/avidity profiling of the antibody complex half-life for polyclonal and monoclonal efficacy screening.

    Science.gov (United States)

    Read, Thomas; Olkhov, Rouslan V; Williamson, E Diane; Shaw, Andrew M

    2015-09-01

    A unified approach to affinity screening for Fab and Fc interactions of an antibody for its antigen and FcγR receptor has been developed. An antigen array is used for the Fab affinity and cross-reactivity screening and protein A/G proxy is the FcγR receptor. The affinities are derived using a simple 1:1 binding model with a consistent error analysis. The association and dissociation kinetics are measured over optimised times for accurate determination. The Fab/Fc affinities are derived for ten antibodies: mAb-actin (mouse), pAb-BSA (sheep), pAb-collagen V (rabbit), pAb-CRP (goat), mAb-F1 (mouse), mAbs (mouse) 7.3, 12.3, 29.3, 36.3 and 46.3 raised against LcrV in Yersinia pestis. The rate of the dissociation of antigen-antibody complexes relates directly to their immunological function as does the Fc-FcγR complex and a new half-life plot has been defined with a Fab/Fc half-life range of 17-470 min. The upper half-life value points to surface avidity. Two antibodies that are protective as an immunotherapy define a Fab half-life >250 min and an Fc half-life >50 min as characteristics of ideal interactions which can form the basis of an antibody screen for immunotherapy. PMID:26187320

  19. Evaluation of 177Lu-DOTA-labeled aglycosylated monoclonal anti-L1-CAM antibody chCE7: influence of the number of chelators on the in vitro and in vivo properties

    International Nuclear Information System (INIS)

    Introduction: In this study, we optimized the 1,4,7,10-tetraazacyclododecane-N-N'-N''-N''''-tetraacetic acid (DOTA) chelator-to-antibody (c/a) ratio for the aglycosylated variant of the anti-L1-CAM antibody chCE7 (chCE7agl), providing high specific activity and low liver uptake in 177Lu-labeled form. Methods: chCE7agl was substituted with increasing molar excess of DOTA-NCS. The number of chelators coupled to the antibody and the binding affinities to target tumor cells (IC5 values) of the resulting immunoconjugates were determined. The different immunoconjugates were labeled with 177Lu; specific activity was measured, and metabolic stability was analyzed in human plasma. The effect of different c/a ratios on blood clearance and liver uptake was tested in nude mice. Changes of the protein backbone structure were analyzed by circular dichroism spectroscopy. Results: chCE7agl was substituted with 7, 12 or 15 DOTA ligands. The IC5 concentrations displacing radioiodinated chCE7 antibody increased with the number of chelators (1.5-fold with 7 ligands, 2.5-fold with 12 ligands and a 5-fold increase with 15 ligands). The highest specific activity for 177Lu-DOTA-chCE7agl was obtained with a c/a ratio of 12 (106 MBq/mg). Radioimmunoconjugates were stable in human plasma for at least 24 h. Blood clearance and liver uptake were measured after 24 h (c/a ratios of 12 and 15) or 48 h (c/a ratio of 7). The liver-to-blood ratios were 0.35±0.14 (7 ligands), 0.77±0.19 (12 ligands) and 17.85±3.44 (15 ligands). Conclusions: DOTA-chCE7agl conjugates with a c/a ratio of 12 combined high specific activity with good in vitro and in vivo properties. The rapid elimination rate from the blood and the high uptake in the liver of chCE7agl substituted with 15 DOTA ligands were found not to be due to conformational changes of the antibody backbone structure

  20. Radioimmunodetection of lymph node invasion in prostatic cancer. The use of iodine-123 (123I)-labeled monoclonal anti-prostatic acid phosphatase (PAP) 227 A F(ab')2 antibody fragments in vivo

    International Nuclear Information System (INIS)

    The therapeutic indications in prostatic cancer depend on the regional and distant extension of the cancer and are difficult to assess before lymphadenectomy. Radioimmunodetection of lymph node involvement with monoclonal anti-prostatic acid phosphatase (PAP) antibodies can be proposed as a noninvasive alternative to lymphadenectomy. Fifteen patients with various stages of histologically proven prostatic cancer were examined by immunolymphoscintigraphy (ILS) before treatment to detect lymph node metastases. These patients had Stage A (n = 7), Stage B (n = 3), Stage C (n = 2), and Stage D (n = 3) tumors. They received between 100 and 400 micrograms of monoclonal antibody 227 A in the form of F(ab')2 fragments labeled with iodine-123 (123I). The antibody was injected directly into the periprostatic area. ILS images were obtained after 1, 3, 6, and 24 hours. Three days later, each patient underwent a lymphadenectomy for histologic examination. The results of the histologic examination and ILS were compared. In ten patients, the examination did not show any images capable of being interpreted as lymphadenopathy and histologic examination confirmed the integrity of the nodes examined. In five cases, scintigraphy suggested the presence of lymph node invasion by prostatic cancer and this was confirmed by histologic examination in three of the five cases. Overall, in terms of lymphadenopathy, this examination had a sensitivity of 100% and a specificity of 83%. Therefore, ILS appears to be capable of detecting lymph node metastases in prostatic cancer

  1. Effects of tumour mass and circulating antigen on the biodistribution of 111In-labelled F(ab')2 fragments of human prostatic acid phosphatase monoclonal antibody in nude mice bearing PC-82 human prostatic tumor xenografts

    International Nuclear Information System (INIS)

    We have evaluated the effects of tumour mass and circulating antigen (prostatic acid phosphatase, PAP) on the biodistribution and the incorporation of 111In-labelled F(ab')2 monoclonal antibody (MoAb) fragments directed against human PAP into human prostatic tumours (PC-82; 0.1-8.9 g) growing in nude mice. The radioactivities in the blood, liver, spleen, kidney and tumour were compared at 1, 3, 4 and 6 days after the intravenous administration of the antibody fragments. There was a significant correlation between the tumour size and the serum PAP concentration in the model employed. Even tissue of a small tumour (111In-labelled F(ab')2 fragments. This relationship had levelled off by 72 h and most likely reflected a better vascularisation of the smaller tumours. Our results show that the increase in tumour size and in the concentration of circulating antigen in the blood led to decreased tumour-to-blood ratios, since there was a tendency for higher blood activities in mice with larger tumours and higher serum PAP concentrations. There was no correlation between tumour size and label uptake by the liver during the follow-up over 144 h, although serum PAP concentrations ranged from 3.1 μg/l to 352 μg/l. On the other hand, when compared with our previous data obtained with non-tumour-bearing mice, there was a significant increase in the uptake by the liver and spleen. These results indicate that even a small concentration of circulating antigen was able to trigger an abnormal change in the biodistribution of MoAbs. (orig.)

  2. Barcoding of live human PBMC for multiplexed mass cytometry*

    OpenAIRE

    Mei, Henrik E; Leipold, Michael D.; Schulz, Axel Ronald; Chester, Cariad; Maecker, Holden T.

    2015-01-01

    Mass cytometry is developing as a means of multiparametric single cell analysis. Here, we present an approach to barcoding separate live human PBMC samples for combined preparation and acquisition on a CyTOF® instrument. Using six different anti-CD45 antibody (Ab) conjugates labeled with Pd104, Pd106, Pd108, Pd110, In113, and In115, respectively, we barcoded up to 20 samples with unique combinations of exactly three different CD45 Ab tags. Cell events carrying more than or less than three dif...

  3. 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

  4. Pharmacokinetics and biodistribution of 177Lu-labeled multivalent single-chain Fv construct of the pancarcinoma monoclonal antibody CC49

    International Nuclear Information System (INIS)

    Lutetium-177 (177Lu) is a radionuclide of interest for radioimmunoimaging (RII) and radioimmunotherapy (RIT) on account of its short half-life (161 h) and the ability to emit both β and γ radiation. Single-chain Fv (scFv) constructs have shown advancement in cancer diagnosis and therapy due to the pharmacokinetics advantage and seem to be intriguing tools in oncology. The objective of this study was to evaluate the pharmacokinetics and biodistribution characteristics of the 177Lu-labeled tetravalent scFv of CC49 MAb and intact CC49 IgG in vivo. Conjugation and labeling conditions of multivalent scFv with 177Lu were optimized without affecting integrity and immunoreactivity. For this purpose, multivalent scFv constructs dimer, sc(Fv)2; tetramer, [sc(Fv)2]2 of the MAb CC49 were expressed as secretory proteins in Pichia pastoris. The purified scFv constructs and IgG form of CC49 were conjugated with a bifunctional chelating agent, ITCB-DTPA, and labeled with 177Lu. The comparative biodistribution, blood clearance, and tumor-targeting characteristics of 177Lu-labeled tetravalent [sc(Fv)2 ]2 construct of CC49 MAb and intact CC49 IgG were investigated in the athymic mice bearing LS-174T xenografts. Approximately, 90% of 177Lu incorporation was achieved using ITCB-DTPA chelator, and the labeled immunoconjugates maintained integrity and immunoreactivity. Blood clearance studies demonstrated an alpha half-life (t1/2 α) of 177Lu-labeled [sc(Fv)2 ]2 and IgG of CC49 at 4.40 and 9.50 min and a beta half-life (t1/2 β) at 375 and 2,193 min, respectively. At 8 h post administration, the percent of the injected dose accumulated/gram (%ID/g) of the LS-174T tumor was 6.4 ±1.3 and 8.9 ±0.6 for 177Lu-labeled [sc(Fv)2 ]2 and IgG of CC49, respectively, in the absence of l-lysine. The corresponding values were 8.0 ±0.6 and 8.4 ±1.2 in the presence of l-lysine. Renal accumulation of [sc(Fv)2 ]2 was significantly (p <0.005) reduced in the presence of l-lysine. (orig.)

  5. Pharmacokinetics and biodistribution of {sup 177}Lu-labeled multivalent single-chain Fv construct of the pancarcinoma monoclonal antibody CC49

    Energy Technology Data Exchange (ETDEWEB)

    Chauhan, Subhash C.; Jain, Maneesh; Moore, Erik D.; Wittel, Uwe A.; Batra, Surinder K. [University of Nebraska Medical Center, Department of Biochemistry and Molecular Biology, Omaha, NE (United States); Li, Jing; Gwilt, Peter R. [University of Nebraska Medical Center, College of Pharmacy, Omaha, NE (United States); Colcher, David [Beckman Research Institute at City of Hope National Medical Center, Department of Radioimmunotherapy, Duarte, CA (United States)

    2005-03-01

    Lutetium-177 ({sup 177}Lu) is a radionuclide of interest for radioimmunoimaging (RII) and radioimmunotherapy (RIT) on account of its short half-life (161 h) and the ability to emit both {beta} and {gamma} radiation. Single-chain Fv (scFv) constructs have shown advancement in cancer diagnosis and therapy due to the pharmacokinetics advantage and seem to be intriguing tools in oncology. The objective of this study was to evaluate the pharmacokinetics and biodistribution characteristics of the {sup 177}Lu-labeled tetravalent scFv of CC49 MAb and intact CC49 IgG in vivo. Conjugation and labeling conditions of multivalent scFv with {sup 177}Lu were optimized without affecting integrity and immunoreactivity. For this purpose, multivalent scFv constructs dimer, sc(Fv){sub 2}; tetramer, [sc(Fv){sub 2}]{sub 2} of the MAb CC49 were expressed as secretory proteins in Pichia pastoris. The purified scFv constructs and IgG form of CC49 were conjugated with a bifunctional chelating agent, ITCB-DTPA, and labeled with {sup 177}Lu. The comparative biodistribution, blood clearance, and tumor-targeting characteristics of {sup 177}Lu-labeled tetravalent [sc(Fv){sub 2} ]{sub 2} construct of CC49 MAb and intact CC49 IgG were investigated in the athymic mice bearing LS-174T xenografts. Approximately, 90% of {sup 177}Lu incorporation was achieved using ITCB-DTPA chelator, and the labeled immunoconjugates maintained integrity and immunoreactivity. Blood clearance studies demonstrated an alpha half-life (t{sub 1/2} {alpha}) of {sup 177}Lu-labeled [sc(Fv){sub 2} ]{sub 2} and IgG of CC49 at 4.40 and 9.50 min and a beta half-life (t{sub 1/2} {beta}) at 375 and 2,193 min, respectively. At 8 h post administration, the percent of the injected dose accumulated/gram (%ID/g) of the LS-174T tumor was 6.4 {+-}1.3 and 8.9 {+-}0.6 for {sup 177}Lu-labeled [sc(Fv){sub 2} ]{sub 2} and IgG of CC49, respectively, in the absence of l-lysine. The corresponding values were 8.0 {+-}0.6 and 8.4 {+-}1.2 in the

  6. Supplemental treatment of rheumatoid arthritis with natural milk antibodies against enteromicrobes and their toxins: results of an open-labelled pilot study

    Directory of Open Access Journals (Sweden)

    Matsuno Takeo

    2011-01-01

    Full Text Available Abstract Background Environmental factors, particularly commensal bacteria in the gastrointestinal tract, may be involved in the pathogenesis of rheumatoid arthritis (RA. The aim of this study was to evaluate whether natural milk antibodies against a wide spectrum of pathogenic enteromicobes and their toxins modify the disease activity in RA. Methods Twenty patients with RA, whose disease activity was uncontrolled by authentic medications due to drug resistance, complications and/or risk factors were treated for 3 months with an oral administration of a whey protein concentrate (WPC containing high levels of natural milk antibodies. Eighteen background-matched RA patients, not supplemented with milk antibody adjunct, were used as controls. Results Statistically significant reduction of arthritis symptoms and improvement of intestinal disorders were observed only in the test group: effective in 8 (44%, possibly effective in 2 (12% and not effective in 8 (44% of 18 patients treated (2 patients withdrew based on an ad hoc "evaluation point", the sum of variables that are improved more than 20% among the 8 core variables used for the American College of Rheumatology (ACR response criteria. This disease modifying effect of the WPC disappeared upon cessation of treatment, but was reappeared upon reintroduction of it. Importantly, 7 of 8 non-responders carry DR15 haplotype (DRB1-1501 and 1502, whereas only 1 of 7 responders was DR15 positive (risk ratio: 6.1. Furthermore, the pre-clinical serum anti-LPS and anti-type II collagen antibody levels in the responders were higher or tended to be higher than those in the non-responders, suggesting that there are 2 sub-types of RA based on an interaction between gastrointestinal pathogens and MHC class II haplotypes. Conclusions The natural milk antibody preparation containing high levels antibodies against pathogenic enteromicrobes and their toxins seems to be effective in a certain RA subset, and deserves

  7. Preparation and near-quantitative Y-90 labelings of monoclonal antibody-macrocylic chelator (MAb-DOTA) conjugates for radioimmunotherapy (RAIT)

    Energy Technology Data Exchange (ETDEWEB)

    Govindan, S.V.; Griffiths, G.L.; Losman, M.J. [Immunomedics, Inc., Morris Plains, NJ (United States)] [and others

    1996-05-01

    The importance of kinetically inert Y-90-DOTA chelate for RAIT is well recognized. The aim of this study was to adapt a published procedure to overcome long-standing problems related to practical preparation of DOTA-MAb conjugates and poor Y-90 incorporation, and further improve upon labeling efficiencies. Using monoactivated DOTA, we have prepared conjugates of a CEA MAb (MN-14), a lymphoma MAb (LL2), their humanized versions (hMN-14 and hLL2), and the respective divalent fragments, and systematically examined the Y-90-labeling parameters. The DOTA/Mab ratios in conjugates were in the 3.0-6.8 range. In competitive CEA-binding assays, unmodified MN-14, MN-14-DOTA (6.8 chelators) and hMN-14-DOTA (4.4 chelators) exhibited very similar binding patterns. Y-90 labeling yields of >90% were obtained using a labeling time of 2 h at 40-45{degrees}C, pH {approximately}5.5, and DOTA/MAb ratio >3. Incorporations (specific activities):>99%for hMN-14-DOTA (103-170 MBa/mg), 94-97% for hLL2-DOTA (107-185 MBa/mg), 93-98%for hLL2F(ab`){sub 2}-DOTA (111 MBa/mg), and >90% for MN14-DOTA (37-185 MBq/mg). Aggregate content was usually less than 5%. Observed high incorporations are due both to the higher temperature used and DOTA/Y-90 molar ratios which readily exceeded a threshold requirement of three. Labeling efficiencies also depended upon the level of trace metal contaminants in the Y-90 shipment. Incubations of Y-90 labeled DOTA conjugates of hMN-14 and hLL2 in serum and in 1 mM DTPA at 37{degrees}C showed no detectable loss of metal over a 10-day period. These results should allow us to routinely use Y-90-DOTA-MAb conjugates in future preclinical and clinical RAIT studies.

  8. Determination of Al, Cd, Cu, Fe in 111InCl3 radiopharmaceuticals solutions by flameless atomic absorption spectrometry: results and effects on 111In labelling of monoclonal antibodies

    International Nuclear Information System (INIS)

    Determination of trace elements in 111InCl3 solution have been carried out by flameless atomic absorption spectrometry. Five successive batches from three European companies have been analysed. The means of measured values range from 4560 to 6930 μ g L-1 for aluminium, 131 to 874 for cadmium, 49 to 300 for copper, 387 to 698 for iron. Using two molar ratio indexes, trivalent metallic traces have been compared to theoretical 111In content. The trace elements largely exceed radioactive material. As Fe and In have similar chemical properties, it results in low specific activity of radioactive complex when labeling monoclonal antibodies by 111In. Using a mathematical model, a detrimental effect of Fe trace levels has been studied. (author)

  9. Imaging studies of breast cancer xenografts. Monoclonal anti-mucin antibodies BM-7 and 12H12 labeled with 99mTC

    International Nuclear Information System (INIS)

    The present study was undertaken to evaluate the correlation of the favourable in vitro characteristics of the anit-mucin Mabs 12H12 and BM-7 with high tumor accumulation in vivo. They were labeled with 99mTc; their biodistribution in nude mice bearing mammary tumor xenograft AR was examined and immunoscintigraphy was performed after 24 h. 99mTc-labeling of the Mabs 12H12 and BM-7 led to tumor uptakes of 20.7% and 8.8% ID/g, respectively, after 48 h. Tumor-to-muscle ratios were 31 (12H12) and 18 (BM-7). Tumor xenografts were clearly visualized in immunoscintigrams. Combination of Mab 12H12 and 99mTc provides high tumor-to-tissue ratios shortly after administration. (orig.)

  10. Thyroid Antibodies

    Science.gov (United States)

    ... be limited. Home Visit Global Sites Search Help? Thyroid Antibodies Share this page: Was this page helpful? Also known as: Thyroid Autoantibodies; Antithyroid Antibodies; Antimicrosomal Antibody; Thyroid Microsomal Antibody; ...

  11. Tumor-specific accumulation of 125I-labeled mouse-human chimeric anti-CEA antibody in a xenografted human cancer model demonstrated by whole-body autoradiography and immunostaining

    International Nuclear Information System (INIS)

    Whole-body autoradiography (WBAR) was used to study the biodistribution of 125I-labeled mouse-human chimeric antibody (Ch F11-39) to carcinoembryonic antigen (CEA) in athymic nude mice bearing the CEA-producing MKN-45 human gastric carcinoma xenografts. Significantly high uptake of 125I-Ch F11-39 in the tumors obtained by tissue-counting technique was confirmed by WBAR of mice of 12, 24, 48, and 96 h postinjection of 125I-Ch F11-39. When compared with histochemical or immunohistochemical staining results of the tumor tissue sections, imaging profiles of 125I-Ch F11-39 obtained by WBARs were topographically correlated with histopathological findings of tissues and immunohistochemical localization of CEA in the tumor tissues, indicating that the accumulation of 125I-Ch F11-39 at the tumor site is based on its specificity for CEA. These results demonstrate that this chimeric antibody may serve as a potential useful diagnostic and/or therapeutic reagent for human CEA-producing cancers

  12. Label-free electrochemical immunosensor for the carcinoembryonic antigen using a glassy carbon electrode modified with electrodeposited Prussian Blue, a graphene and carbon nanotube assembly and an antibody immobilized on gold nanoparticles

    International Nuclear Information System (INIS)

    We described a sensitive, label-free electrochemical immunosensor for the detection of carcinoembryonic antigen. It is based on the use of a glassy carbon electrode (GCE) modified with a multi-layer films made from Prussian Blue (PB), graphene and carbon nanotubes by electrodeposition and assembling techniques. Gold nanoparticles were electrostatically absorbed on the surface of the film and used for the immobilization of antibody, while PB acts as signaling molecule. The stepwise assembly process was investigated by differential pulse voltammetry and scanning electron microscopy. It is found that the formation of antibody-antigen complexes partially inhibits the electron transfer of PB and decreased its peak current. Under the optimal conditions, the decrease of intensity of the peak current of PB is linearly related to the concentration of carcinoembryonic antigen in two ranges (0.2–1.0, and 1.0–40.0 ng·mL−1), with a detection limit of 60 pg·mL−1 (S/N = 3). The immunosensor was applied to analyze five clinical samples, and the results obtained were in agreement with clinical data. In addition, the immunosensor exhibited good precision, acceptable stability and reproducibility. (author)

  13. An ultrasensitive electrochemiluminescent immunoassay for aflatoxin M1 in milk, based on extraction by magnetic graphene and detection by antibody-labeled CdTe quantumn dots-carbon nanotubes nanocomposite.

    Science.gov (United States)

    Gan, Ning; Zhou, Jing; Xiong, Ping; Hu, Futao; Cao, Yuting; Li, Tianhua; Jiang, Qianli

    2013-05-01

    An ultrasensitive electrochemiluminescent immunoassay (ECLIA) for aflatoxins M1 (ATM1) in milk using magnetic Fe3O4-graphene oxides (Fe-GO) as the absorbent and antibody-labeled cadmium telluride quantum dots (CdTe QDs) as the signal tag is presented. Firstly, Fe3O4 nanoparticles were immobilized on GO to fabricate the magnetic nanocomposites, which were used as absorbent to ATM1. Secondly, aflatoxin M1 antibody (primary antibody, ATM1 Ab1), was attached to the surface of the CdTe QDs-carbon nanotubes nanocomposite to form the signal tag (ATM1 Ab1/CdTe-CNT). The above materials were characterized. The optimal experimental conditions were obtained. Thirdly, Fe-GO was employed for extraction of ATM1 in milk. Results indicated that it can adsorb ATM1 efficiently and selectively within a large extent of pH from 3.0 to 8.0. Adsorption processes reached 95% of the equilibrium within 10 min. Lastly, the ATM1 with a serial of concentrations absorbed on Fe-GO was conjugated with ATM1 Ab1/CdTe-CNT signal tag based on sandwich immunoassay. The immunocomplex can emit a strong ECL signal whose intensity depended linearly on the logarithm of ATM1 concentration from 1.0 to 1.0 × 10(5) pg/mL, with the detection limit (LOD) of 0.3 pg/mL (S/N = 3). The method was more sensitive for ATM1 detection compared to the ELISA method. Finally, ten samples of milk were tested based on the immunoassay. The method is fast and requires very little sample preparation, which was suitable for high-throughput screening of mycotoxins in food. PMID:23628784

  14. An Ultrasensitive Electrochemiluminescent Immunoassay for Aflatoxin M1 in Milk, Based on Extraction by Magnetic Graphene and Detection by Antibody-Labeled CdTe Quantumn Dots-Carbon Nanotubes Nanocomposite

    Directory of Open Access Journals (Sweden)

    Ning Gan

    2013-04-01

    Full Text Available An ultrasensitive electrochemiluminescent immunoassay (ECLIA for aflatoxins M1 (ATM1 in milk using magnetic Fe3O4-graphene oxides (Fe-GO as the absorbent and antibody-labeled cadmium telluride quantum dots (CdTe QDs as the signal tag is presented. Firstly, Fe3O4 nanoparticles were immobilized on GO to fabricate the magnetic nanocomposites, which were used as absorbent to ATM1. Secondly, aflatoxin M1 antibody (primary antibody, ATM1 Ab1, was attached to the surface of the CdTe QDs-carbon nanotubes nanocomposite to form the signal tag (ATM1 Ab1/CdTe-CNT. The above materials were characterized. The optimal experimental conditions were obtained. Thirdly, Fe-GO was employed for extraction of ATM1 in milk. Results indicated that it can adsorb ATM1 efficiently and selectively within a large extent of pH from 3.0 to 8.0. Adsorption processes reached 95% of the equilibrium within 10 min. Lastly, the ATM1 with a serial of concentrations absorbed on Fe-GO was conjugated with ATM1 Ab1/CdTe-CNT signal tag based on sandwich immunoassay. The immunocomplex can emit a strong ECL signal whose intensity depended linearly on the logarithm of ATM1 concentration from 1.0 to 1.0 × 105 pg/mL, with the detection limit (LOD of 0.3 pg/mL (S/N = 3. The method was more sensitive for ATM1 detection compared to the ELISA method. Finally, ten samples of milk were tested based on the immunoassay. The method is fast and requires very little sample preparation, which was suitable for high-throughput screening of mycotoxins in food.

  15. Detection of activated platelets in a mouse model of carotid artery thrombosis with 18F-labeled single-chain antibodies

    International Nuclear Information System (INIS)

    Introduction: Activated platelets are key players in thrombosis and inflammation. We previously generated single-chain antibodies (scFv) against ligand-induced binding sites (LIBS) on the highly abundant platelet glycoprotein integrin receptor IIb/IIIa. The aim of this study was the construction and characterisation of a novel 18F PET radiotracer based on this antibody. Methods: ScFvanti-LIBS and control antibody mut-scFv were reacted with N-succinimidyl-4-[18F]fluorobenzoate (S[18F]FB). Radiolabeled scFv was incubated with in vitro formed platelet clots and injected into mice with FeCl3 induced thrombus in the left carotid artery. Clots were imaged in the PET scanner and amount of radioactivity measured using an ionization chamber and image analysis. Assessment of vessel injury as well as the biodistribution of the radiolabeled scFv was studied. Results: After incubation with increasing concentrations of 18F-scFvanti-LIBS clots had retained significantly higher amounts of radioactivity compared to clots incubated with radiolabeled 18F-mut-scFv (13.3 ± 3.8 vs. 3.6 ± 1 KBq, p < 0.05, n = 9, decay corrected). In the in vivo experiments we found an high uptake of the tracer in the injured vessel compared with the non-injured vessel, with 12.6 ± 4.7% injected dose per gram (ID/g) uptake in the injured vessel and 3.7 ± 0.9% ID/g in the non-injured vessel 5 minutes after injection (p < 0.05, n = 6). Conclusions: Our results show that the novel antibody radiotracer 18F-scFvanti-LIBS is useful for the sensitive detection of activated platelets and thrombosis. Advances in knowledge and implications for patient care: We describe the first 18F variant of a scFvanti-LIBS against activated platelets. This diagnostic agent could provide a powerful tool for the assessment of acute thrombosis and inflammation in patients in the future

  16. Radioimmunoscintigraphy of experimental internal carotid arterial thrombi in dogs with 99mTc-labelled monoclonal anti-activated platelet antibody SZ-51

    International Nuclear Information System (INIS)

    The capacity of McAbSZ-51, which is specific for an α-granule membrane protein (GMP-140) expressed on the surface of activated platelets, to bind to the grafted human thrombus in rabbits was studied. The feasibility of imaging thrombus with 99mTc-labelled McAbSZ-51 in the internal carotid artery of dog was also explored. The results showed that McAbSZ-51 could bind to the grafted human thrombus in rabbits. The thrombus in internal carotid artery was clearly discerned at 2 to 6 h after injection of 99mTc-SZ-51, with the optimal imaging time at 2 to 4 h after injection. The radioactivity ratio of thrombus to blood was 6.03 +- 1.09 at 6 to 8 h after injection. It is thus concluded that by using the 99mTc-labelled McAbSZ-51, the early and specific detection of thrombi formed in vivo was fairly possible and feasible. (3 figs., 1 tab.)

  17. Alkaline Phosphatase Tagged Antibodies on Gold Nanoparticles/TiO2 Nanotubes Electrode: A Plasmonic Strategy for Label-Free and Amplified Photoelectrochemical Immunoassay.

    Science.gov (United States)

    Zhu, Yuan-Cheng; Zhang, Nan; Ruan, Yi-Fan; Zhao, Wei-Wei; Xu, Jing-Juan; Chen, Hong-Yuan

    2016-06-01

    This work reports a plasmonic strategy capable of label-free yet amplified photoelectrochemical (PEC) immunoassay for the sensitive and specific detection of model protein p53, an important transcription factor that regulates the cell cycle and functions as a tumor suppressor. Specifically, on the basis of Au nanoparticles (NPs) deposited on hierarchically ordered TiO2 nanotubes (NTs), a protein G molecular membrane was used for immobilization of alkaline phosphatase (ALP) conjugated anti-p53 (ALP-a-p53). Due to the immunological recognition between the receptor and target, the plasmonic charge separation from Au NPs to the conduction band of TiO2 NTs could be influenced greatly that originated from multiple factors. The degree of signal suppression is directly associated with the target concentration, so by monitoring the changes of the plasmonic photocurrent responding after the specific binding, a new plasmonic PEC immunoassay could be tailored for label-free and amplified detection. The operating principle of this study could be extended as a general protocol for numerous other targets of interest. PMID:27150939

  18. Use of Radioactive Ion Beams for Biomedical Research 1. in vivo labelling of monoclonal antibodies with radio-lanthanides and $^{225}$Ac

    CERN Multimedia

    2002-01-01

    % IS330 \\\\ \\\\\\begin{enumerate} \\item The aim of this study was to contribute to developments of new radiopharmaceuticals for tumour diagnosis and therapy. CERN-ISOLDE is the leading facility in the world to provide radioactive ion beams with high selectivity, purity and intensity. Radioisotope production by spallation makes available a complete range of rare earth isotopes having as complete a diversity of types and energy of radiation, of half-life, and of ionic properties as one would wish. The availability of exotic nuclei, e.g. radionuclides of rare earth elements and $^{225}$Ac, opens new possibilities for the development of radiopharmaceuticals for diagnosis and therapy.\\\\ \\\\ \\item Two approaches were followed within the experimental program. The radioactive metal ions are bound either to bio-specific ligands (monoclonal antibodies or peptides) or to unspecific low molecular weight form. The aim of the experimental program is to evaluate relationships between physico-chemical parameters of the tracer m...

  19. Immunoassay of ergotamine and dihydroergotamine using a common /sup 3/H-labelled ligand as tracer for specific antibody and means to overcome experienced pitfalls

    Energy Technology Data Exchange (ETDEWEB)

    Rosenthaler, J.; Munzer, H.; Voges, R.; Andres, H.; Gull, P.; Bolliger, G.

    1984-01-01

    A highly sensitive radioimmunoassay for the determination of ergotamine and dihydroergotamine is described. The limit of detection is about 9 pg/mL blood plasma for both compounds. The specificity of the gamma-globulin, which was prepared from rabbit antiserum, was investigated in the presence of compounds synthesized as possible metabolites. It was found that the tricyclic peptide moiety common to both molecules is an essential structural feature for binding to the gamma-globulin. From dilution experiments with the radioactively labelled compound it followed that ergotamine and to a lesser extent also its dihydro derivative are adsorbed on various tube wall materials using known buffer solutions. A practically insuperable obstacle is rearrangement of ergotamine under the experimental conditions, forming a stereoisomer by inversion at the C-8 position. The equilibrium of ergotamine in equilibrium ergotaminine found in human plasma remains stable under the incubation conditions of the radioimmunoassay.

  20. Food Labels

    Science.gov (United States)

    ... How Can I Help a Friend Who Cuts? Food Labels KidsHealth > For Teens > Food Labels Print A ... have at least 95% organic ingredients. continue Making Food Labels Work for You The first step in ...

  1. A novel multivalent 99mTc-labeled EG2-C4bpα antibody for targeting the epidermal growth factor receptor in tumor xenografts

    International Nuclear Information System (INIS)

    Introduction: The C4b binding protein (C4bp) α/β-chain C-terminal effectively induces polymerization during protein synthesis. Using this fragment and the single-domain antibody EG2, which targets the epidermal growth factor receptor (EGFR), we generated the novel multimeric antibody EG2-C4bpα. We radiolabeled EG2-C4bpα with 99mTc and evaluated its targeting efficiency and pharmacokinetics in tumor xenografts. Methods: EGFR expression and EGFR-EG2-C4bpα binding was evaluated in A431 and OCM-1 cells by Western blotting and flow cytometry, respectively. EG2-C4bpα was radiolabeled with [99mTc(CO)3(OH2)3]+ using a tricarbonyl vial followed by purification on a PD-10 column. In vitro studies with 99mTc-EG2-C4bpα were performed in A431 and/or OCM-1 cells. Single photon emission computed tomography (SPECT) imaging and biodistribution studies were carried out in 99mTc-EG2-C4bpα-injected mice bearing A431- and OCM-1-derived tumors. EGFR immunofluorescent staining in A431 and OCM-1 tumors was performed. Results: A431 cells showed higher EGFR expression levels than OCM-1 cells, and flow cytometry confirmed EG2-C4bpα bound more A431 cells than OCM-1 cells. 99mTc-EG2-C4bpα was successfully prepared with radiochemical yields of 30.3–50.4%. The binding affinity of 99mTc-EG2-C4bpα to A431 cells was approximately 20 nM. 99mTc-EG2-C4bpα specifically bound A431 cells and this binding was blocked by 41% in the presence of 50 nM excess unlabeled EG2-C4bpα. In vivo radioactivity uptake in A431 tumors was detected 2 h after 99mTc-EG2-C4bpα administration and sustained up to 18 h. The highest ratio of A431 tumor-to-muscle and tumor-to-blood was 3.69 ± 0.48 at 10 h and 0.77 ± 0.14 at 20 h, respectively. Excess unlabeled EG2-C4bpα blocked radioactivity uptake in A431 tumors by 55% at 10 h. 99mTc-EG2-C4bpα was barely detectable in OCM-1 tumors, and biodistribution analysis confirmed that radioactivity uptake was significantly lower than in A431 tumors. Conclusions: 99m

  2. Phase I/II trial of 111In-labeled anti-CEA monoclonal antibody (111In-ZCE-025) in diagnosis of colorectal cancer

    International Nuclear Information System (INIS)

    A phase I/II study of imaging with radiolabeled anti-CEA monoclonal antibody, 111In-ZCE-025, was carried out in patients with colorectal cancers as a joint research project at 5 hospitals in Japan. There were 24 patients, 22 of whom were judged to be evaluable. Nineteen had primary lesions with or without metastatic lesions, two had local recurrences, and one had only metastatic lesions. On the patient basis, 21 of the 22 (95.5%) were judged to be positive. Of the 40 known lesions, planar imaging detected 24 (60.0%), whereas combined imaging (planar and single photon emission computed tomography, SPECT) detected 29 (72.5%). Surgery disclosed another 22 new lesions, two (9.1%) of which had been detected by the planar and four (18.2%) by the combined imagings. As for the newly visualized sites, on the other hand, planar imaging depicted 10, two of which were true positives (20.0%), whereas combined imaging depicted 20 and four of them were true positives (20.0%). These low positive predictive values for newly visualized sites were due to many false positive lymph nodes. In conclusion, this method will be useful for preoperative screening and diagnosis of local recurrence of colorectal cancers. But the formation of HAMA should be taken into consideration when this method is repeatedly used. At present, for metastatic foci in lymph nodes, this method possesses only a complementary role. (author)

  3. The labelling of adriamycin-loaded human serum albumin immuno-nanoparticles led by monoclonal antibodies with 131I and its anti-hepatoma effect in vivo

    International Nuclear Information System (INIS)

    The pharmaceutics character, targeting to hepatoma and anticancer activity in nude mice of adriamycin-loaded human serum albumin immuno-nanoparticles (ADR-HSA-NP) against hepatoma led by anti-human hepatoma monoclonal antibodies HAb18 are studied. The results show that effective loaded drug dose of HAb18-ADR-HSA-NP is 1.44%, which is lower than ADR-HSA-NP (1.69%); HAb18-ADR-HSA-NP slowly releases drug ADR and its maximum releasing drug dose (41%) is obviously lower than ADR-HSA-NP (65%) (P 131I-HAb18-ADR-HSA-NP mainly accumulates in liver and its liver-taxis and stability are better than 131I-ADR-HSA-NP in nude mice by intravenous injection; HAb18-ADR-HSA-NP mainly accumulates in tumor and its accumulation amount of tumor is higher than ADR-HSA-NP (P < 0.05), and has obvious inhibiting cancer action and its inhibitory rate of cancer is also higher than ADR-HSA-NP (P < 0.05) by tumor injection. So, HAb18-ADR-HSA-NP can bind and inhibit hepatoma cell from growing in vivo

  4. Biodistribution in normal mice of an 111In-labelled prostatic acid phosphatase-specific antibody and its F(ab')2 fragments derivatized site-specifically or via bicyclic diethylenetriaminepentaacetic acid anhydride

    International Nuclear Information System (INIS)

    We examined the optimization of derivatization of monoclonal antibodies and their fragments intended for use as radiopharmaceutical in radioimaging and/or radioimmunotherapy of prostatic cancer. Two different principles were used to conjugate (DTPA) to a monoclonal antibody (Mab, subclass IgG1) raised against human prostatic acid phosphatase (PAP). In addition, the F(ab')2 fragments of this Mab were also derivatized. The biodistribution of the 111In-labelled derivatives was investigated in normal mice. All the derivatives of IgG1 demonstrated a slower blood clearance than the corresponding derivatives of the F(ab')2 fragments. This property was particularly pronounced in the site-specifically conjugated derivatives of IgG1. All the derivatives studied accumulated in the liver, kidney, and spleen. The CA-DTPA derivatives of F(ab')2 fragments showed the highest kidney-to-blood ratios of radioactivity. The derivatives of IgG1 showed a higher percentage of the injected dose in liver and spleen tissues than the derivatives of the F(ab')2 fragments. The F(ab')2 fragments studied also gave rise to site-specific derivatives, which demonstrated that carbohydrates were also present in this part of the molecule. They behaved similarly to the CA-DTPA F(ab')2 derivative in other respects, but the kidney accumulation was lower at 72 and 120 h. The F(ab')2 fragments studied would be better suited for radioimaging than the derivatives of the IgG1 studied. In contrast, the derivatives of IgG1, especially the p-NH2-Bz-DTPA conjugate, might be more suitable candidates for the development of therapeutic agents. (orig.)

  5. Clinical application study of bone marrow immunoscintigraphy using 99mTc-labelled anti-granulocyte monoclonal antibody BW250/183

    International Nuclear Information System (INIS)

    Objective: To study: (1) The labelling method of 99mTc-BW250/183 and its organ distribution pattern after injection. (2) The clinical value of bone marrow immunoscintigraphy of evaluation of patients with aplastic anemia. (3) The clinical value of bone marrow immunoscintigraphy of determination of bone metastasis. Methods: (1) Whole body imaging was performed to one volunteer after injection of 555 MBq 99mTc-BW250/183, meanwhile, 2 ml blood samples was taken from a cubital vein. The percentage of radioactivity of different organs and the kinetic data of in-vivo 99mTc-BW250/183 was then calculated. In all the blood samples the peripheral leukocytes were counted by a standard procedure. (2) Bone marrow immunoscintigraphy were performed to 8 patients with aplastic anemia 4 h after injection of 99mTc-BW250/183, 6 of them also underwent bone marrow imaging with 99mTc-SC. (3) Bone marrow immunoscintigraphy and conventional bone scan were performed to 14 patients with suspected bone metastases to detect bone metastases. The results was compared with X-ray, X-CT or MRI. Results: 99mTc-BW250/183 is a safe and ideal bone marrow imaging agent. Bone marrow immunoscintigraphy plays an important role in evaluating patients with aplastic anemia and determining bone metastases

  6. Improved immunoscintigraphy by subcutaneous injection of sup(99m)Tc or 111In labelled F(ab')2 fragments of an anti-melanoma monoclonal antibody

    International Nuclear Information System (INIS)

    Technetium-99m and/or 111In labelled F(ab')2 fragments of a melanoma associated MoAb 225.28S were injected i.v. in 80 patients affected by stage I to IV malignant melanoma. 75% of metastatic lesions already documented by other methods were detected by immunoscintigraphy, which was also capable of detecting a certain number of unknown metastases. The authors observed a lower percentage of positive scans in liver, lung and skin because of the poor tumour to background ratio. In some patients, subcutaneous (s.c.) injection allowed visualization documented metastases undetected by i.v. administration. An equal amount on non-specific F(ab')2 fragments (MoAb 4C4) injected s.c. as a negative control showed no positive scans. Clinical studies and chromatographic patterns of patient serum samples suggest that the s.c. route of administration offers, with respect to the the i.v. route, the advantage of reducing vascular background and aspecific accumulation in liver, probably because of retention of possible contaminants by the lymphatic system. (author)

  7. Biodistribution and γ imaging of 125I-labeled goat anti-human IgG polyclonal antibody in nude mice bearing human colon cancer xenografts

    International Nuclear Information System (INIS)

    The possibility of IgG secreted from tumor cells as a target for radioimmunoimaging and targeted therapy of cancers were investigated. Goat anti-human IgG polyclonal anti- body (GAHG) was radioiodinated using Iodogen method, and the in vitro stability and pharmacokinetics were evaluated. The biodistribution and γ imaging of 125I-GAHG were performed in nude mice bearing HT-29 human colon cancer xenografts. 125I-GAHG showed good in vitro stability, and its blood clearance was defined as a two-compartment model, with T1/2α and T1/2β were 1.19 h and 43.99 h, respectively. The tumor uptake of 125I-GAHG was higher than that of 125I-labeled normal goat IgG control (125I-GIgG). 125I-GAHG showed good tumor retention when injecting via intra-tumor. In the biodistribution study, the highest tumor uptake of 125I-GAHG was 6.71±2.19%ID/g at 72 h postinjection and the T/NT increased along with the postinjection time. The results show that 125I-GAHG have good tumor-specific uptake which may provide a novel idea for radioimmunoimaging and targeted therapy of cancers. (authors)

  8. An Open Label Phase 1b Dose Escalation Study of TRC105 (Anti-Endoglin Antibody) with Bevacizumab in Patients with Advanced Cancer

    Science.gov (United States)

    Gordon, Michael S.; Robert, Francisco; Matei, Daniela; Mendelson, David S.; Goldman, Jonathan W.; Chiorean, E. Gabriela; Strother, Robert M.; Seon, Ben K.; Figg, William D.; Peer, Cody J.; Alvarez, Delia; Adams, Bonne J.; Theuer, Charles P.; Rosen, Lee S.

    2014-01-01

    Purpose Endoglin, an endothelial cell membrane receptor expressed on angiogenic tumor vessels, is essential for angiogenesis and upregulated in the setting of VEGF inhibition. TRC105 is an anti-endoglin IgG1 monoclonal antibody that potentiates VEGF inhibitors in preclinical models. This study assessed safety, pharmacokinetics, and anti-tumor activity of TRC105 in combination with bevacizumab. Patients and Methods Patients (n=38) with advanced solid tumors, Eastern Cooperative Group performance status 0–1, and normal organ function were treated with escalating doses of TRC105 plus bevacizumab until disease progression or unacceptable toxicity using a standard 3 + 3 phase 1 design. Results TRC105 and bevacizumab were well tolerated at their recommended single agent doses (10 mg/kg) when the initial dose of TRC105 was delayed by one week and divided over two days to limit the frequency of headache. The concurrent administration of bevacizumab and TRC105 did not otherwise potentiate known toxicities of TRC105 or bevacizumab. Hypertension and proteinuria were observed, though not at rates expected for single agent bevacizumab. Several patients who had previously progressed on bevacizumab or VEGF receptor tyrosine kinase inhibitor (VEGFR TKI) treatment experienced reductions in tumor volume, including two partial responses by RECIST, and six remained without progression for longer periods than during their prior VEGF inhibitor therapy. Conclusion TRC105 was well tolerated with bevacizumab and clinical activity was observed in a VEGF inhibitor refractory population. Ongoing clinical trials are testing TRC105 in combination with bevacizumab in glioblastoma, and with VEGFR TKIs in renal cell carcinoma, hepatocellular carcinoma, and soft tissue sarcoma. PMID:25261556

  9. Efficacy of Rituximab in Refractory Inflammatory Myopathies Associated with Anti- Synthetase Auto-Antibodies: An Open-Label, Phase II Trial.

    Directory of Open Access Journals (Sweden)

    Yves Allenbach

    Full Text Available Anti-synthetase syndrome (anti-SS is frequently associated with myositis and interstitial lung disease (ILD. We evaluated prospectively, in a multicenter, open-label, phase II study, the efficacy of rituximab on muscle and lung outcomes.Patients were enrolled if they were refractory to conventional treatments (prednisone and at least 2 immunosuppressants. They received 1 g of rituximab at D0, D15, and M6. The primary endpoint was muscular improvement based on manual muscular testing (MMT10, Kendall score in 10 muscles at M12. Secondary endpoints were normalization of creatine kinase (CK level, ILD improvement based on forced vital capacity and/or diffuse capacity for carbon monoxide, and number and/or doses of associated immunosuppressants.Twelve patients were enrolled, and 10 completed the study. Only 2 patients presented an improvement of at least 4 points on at least two muscle groups (primary end-point. Overall, seven patients had an increase of at least 4 points on MMT10. CK level decreased from 399 IU/L (range, 48-11,718 to 74.5 IU/L (range, 40-47,857. Corticosteroid doses decreased from 52.5 mg/d (range, 10-70 to 9 mg/d (range, 7-65 and six patients had a decrease in the burden of their associated immunosuppressants. At baseline, all 10 patients presented with ILD. At M12, improvement of ILD was observed in 5 out of the 10 patients, stabilization in 4, and worsening in 1.This pilot study of rituximab treatment in patients with refractory anti-SS provided data on evolution of muscular and pulmonary parameters. Rituximab should now be evaluated in a larger, controlled study for this homogenous group of patients.Clinicaltrials.gov NCT00774462.

  10. Human pharmacokinetics, biodistribution and dosimetry of the kit of monoclonal antibody IOR EGF/R3 labelled with {sup 99m} Tc

    Energy Technology Data Exchange (ETDEWEB)

    Torres, L.A.; Ramos, M.; Perera, A.; Hernandez, A.; Iznaga, M.E. N. [Solano, Ivette Alvarez, Jose L. Rodriguez. Centro de InvestigacionesClinicas. 34 no.4501 e/45 y 47 Kohly, Playa, C. Habana (Cuba)

    1998-12-31

    The aim of this work was to assess the human pharmacokinetics, biodistribution and dosimetry of the {sup 99m} Tc-labeled MAb ior egf/r3. Five patients were included in the biodistribution and dosimetric studies and three in the pharmacokinetic analysis. Multiple blood and urine samples we recollected and sequential anterior and posterior whole-body scintigraphies u pto 24 hr post-injection were performed to all patients . The internal radiation dosimetry was estimated from gamma camera imaging data using the methods developed by the Medical Internal radiation dosimetry (MIRD)committee. Raw data were computed from operations between gamma graphic images and regions of interest (ROI) using the Bio-Dose software and time-activity curves were calculated in order to determine the residence times of the source organs. The Pharmacokinetics and Biodistribution results showed that this compound have a bio exponential plasmatic and blood clearance with a rapid biodistribution phase of 9.1 {+-} 8.4 min and 12.2{+-}4.4 min, respectively, and a slower elimination phase of 6.6 {+-} 1.6 hr and 10.8 {+-} 6.8 hr. respectively. The urinary and hepatobiliary excretion showed 4.7 {+-} 0.4 % and 9.9 {+-} 1.8 % of the total administered dose,eliminated by these ways. Liver was the target organ of this product and had an uptake peak at 1 hr post-injection (61.2%) and a great retention of the MAb(T 1/2 eff = 5.3 hr, T 1/2 Biol. = 45.0 hr). The dosimetric results showed that liver, gallbladder and spleen received the higher absorbed. The effective dose and the effective equivalent dose were 1,2E-01 mSv/MBq and 9,2E-02 mSv/MBq respectively. These results allow to see the i or egf/r3 kit in a safe and controlled way. (Author)

  11. New Insights in Tissue Distribution, Metabolism, and Excretion of [3H]-Labeled Antibody Maytansinoid Conjugates in Female Tumor-Bearing Nude Rats.

    Science.gov (United States)

    Walles, Markus; Rudolph, Bettina; Wolf, Thierry; Bourgailh, Julien; Suetterlin, Martina; Moenius, Thomas; Peraus, Gisela; Heudi, Olivier; Elbast, Walid; Lanshoeft, Christian; Bilic, Sanela

    2016-07-01

    For antibody drug conjugates (ADCs), the fate of the cytotoxic payload in vivo needs to be well understood to mitigate toxicity risks and properly design the first in-patient studies. Therefore, a distribution, metabolism, and excretion (DME) study with a radiolabeled rat cross-reactive ADC ([(3)H]DM1-LNL897) targeting the P-cadherin receptor was conducted in female tumor-bearing nude rats. Although multiple components [total radioactivity, conjugated ADC, total ADC, emtansine (DM1) payload, and catabolites] needed to be monitored with different technologies (liquid scintillation counting, liquid chromatography/mass spectrometry, enzyme-linked immunosorbent assay, and size exclusion chromatography), the pharmacokinetic data were nearly superimposable with the various techniques. [(3)H]DM1-LNL897 was cleared with half-lives of 51-62 hours and LNL897-related radioactivity showed a minor extent of tissue distribution. The highest tissue concentrations of [(3)H]DM1-LNL897-related radioactivity were measured in tumor. Complimentary liquid extraction surface analysis coupled to micro-liquid chromatography-tandem mass spectrometry data proved that the lysine (LYS)-4(maleimidylmethyl) cyclohexane-1-carboxylate-DM1 (LYS-MCC-DM1) catabolite was the only detectable component distributed evenly in the tumor and liver tissue. The mass balance was complete with up to 13.8% ± 0.482% of the administered radioactivity remaining in carcass 168 hours postdose. LNL897-derived radioactivity was mainly excreted via feces (84.5% ± 3.12%) and through urine only to a minor extent (4.15% ± 0.462%). In serum, the major part of radioactivity could be attributed to ADC, while small molecule disposition products were the predominant species in excreta. We show that there is a difference in metabolite profiles depending on which derivatization methods for DM1 were applied. Besides previously published results on LYS-MCC-DM1 and MCC-DM1, maysine and a cysteine conjugate of DM1 could be

  12. Human pharmacokinetics, biodistribution and dosimetry of the kit of monoclonal antibody IOR EGF/R3 labelled with 99m Tc

    International Nuclear Information System (INIS)

    The aim of this work was to assess the human pharmacokinetics, biodistribution and dosimetry of the 99m Tc-labeled MAb ior egf/r3. Five patients were included in the biodistribution and dosimetric studies and three in the pharmacokinetic analysis. Multiple blood and urine samples we recollected and sequential anterior and posterior whole-body scintigraphies u pto 24 hr post-injection were performed to all patients . The internal radiation dosimetry was estimated from gamma camera imaging data using the methods developed by the Medical Internal radiation dosimetry (MIRD)committee. Raw data were computed from operations between gamma graphic images and regions of interest (ROI) using the Bio-Dose software and time-activity curves were calculated in order to determine the residence times of the source organs. The Pharmacokinetics and Biodistribution results showed that this compound have a bio exponential plasmatic and blood clearance with a rapid biodistribution phase of 9.1 ± 8.4 min and 12.2±4.4 min, respectively, and a slower elimination phase of 6.6 ± 1.6 hr and 10.8 ± 6.8 hr. respectively. The urinary and hepatobiliary excretion showed 4.7 ± 0.4 % and 9.9 ± 1.8 % of the total administered dose,eliminated by these ways. Liver was the target organ of this product and had an uptake peak at 1 hr post-injection (61.2%) and a great retention of the MAb(T 1/2 eff = 5.3 hr, T 1/2 Biol. = 45.0 hr). The dosimetric results showed that liver, gallbladder and spleen received the higher absorbed. The effective dose and the effective equivalent dose were 1,2E-01 mSv/MBq and 9,2E-02 mSv/MBq respectively. These results allow to see the i or egf/r3 kit in a safe and controlled way. (Author)

  13. The purification of affinity-labelled active-site peptides

    International Nuclear Information System (INIS)

    The isolation of the labelled peptide from the protein digest, following the affinity labelling of the active sites of enzymes or antibodies, is described. Single-step affinity chromatography utilises the affinity of the native enzymes or antibody for the ligand used to label the same protein. The labelled peptide is the only one in the digest that displays affinity for the immobilised protein and can be released with eluants that dissociate the protein-ligand complex. (Auth.)

  14. Pharmacological selection of antibodies for immunoscintigraphy

    International Nuclear Information System (INIS)

    The recent development of hybridoma technology has resulted in the production of monoclonal antibodies that recognize a variety of tumor antigens. Many antibodies have been developed and some of them are used with different success in clinical practice. A list of criteria is proposed for the selection of antibodies suitable for imaging studies illustrated with the example of two monoclonal antibodies anti-CEA and 19.9 used in colorectal carcinoma imaging. Monoclonal antibodies obtained today are not truly tumor-specific, they are tumor-associated; this suggests that some cross-reactions with normal tissues exist. For immunoscintigraphical use it is important to select antibodies which procedure high tumor cell staining with limited reactivity against normal tissues. Antibodies can be separated into F(ab')2 and Fab fragments which diffuse more easily into the tumor with a rapid clearance from the circulation giving higher tumor to normal tissues ratio at an early time. Antibodies with both high affinity and avidity towards tumor cell receptors produce better imaging results. Antibodies can be labelled directly with iodine or technetium and with indium using chelating agents. In vivo kinetics of radiolabelled antibodies are very different considering the nuclide and the labelling method used. Pharmacokinetics on nude mice grated with human tumors are very useful for selecting the most appropriate nuclide antibody fragment and the most efficient labelling technique for a given application. (author)

  15. Wasteful Labeling

    OpenAIRE

    Mahenc, Philippe

    2009-01-01

    The role of labeling is to solve the adverse selection problem caused by unsubstantiated claims from firms. The problem however is likely to remain unsolved if the labeling agency is not trustworthy.The agency can be suspected to divert the fees charged for labeling from their primary purpose of collecting information in order to raise excessive revenue. This paper addresses this issue and shows that labeling may be wasteful if the agency is likely to be untrustworthy. To award firms green la...

  16. Antithyroid microsomal antibody

    Science.gov (United States)

    Thyroid antimicrosomal antibody; Antimicrosomal antibody; Microsomal antibody; Thyroid peroxidase antibody; TPOAb ... Granulomatous thyroiditis Hashimoto thyroiditis High levels of these antibodies have also been linked to an increased risk ...

  17. Nutrition Labeling

    DEFF Research Database (Denmark)

    Grunert, Klaus G

    2013-01-01

    because consumers will avoid products that the label shows to be nutritionally deficient, but also because food producers will try to avoid marketing products that appear, according to the label, as nutritionally problematic, for example, because of a high content of saturated fat or salt. Nutrition......Nutrition labeling refers to the provision of information on a food product’s nutritional content on the package label. It can serve both public health and commercial purposes. From a public health perspective, the aim of nutrition labeling is to provide information that can enable consumers...... to make healthier choices when choosing food products. Nutrition labeling is thus closely linked to the notion of the informed consumer, that chooses products according to their aims, on the basis of the information at their disposal. Because many consumers are assumed to be interested in making healthy...

  18. Preparation of radiopharmaceuticals labeled with gallium and indium

    International Nuclear Information System (INIS)

    This project was designed to carry out routine production of Ga-68 labeled radiopharmaceuticals for use, particularly in pulmonary studies; to continue work on the development of Ga-68 labeled radiopharmaceuticals that could be used with positron emission tomography; to evaluate indium-111 and possibly gallium-68 labeled antibodies in animal models; to continue development of new chelates and bifunctional chelates for use as radiopharmaceuticals; and to develop new approaches to the delivery of radiopharmaceuticals to the brain. We have made major advances in all of these areas. In area one, we have shown that gallium-68 radiopharmaceuticals can be produced routinely under robotic control for patient studies. This has resulted in several publications by us and by our collaborators in the Pulmonary Division at Washington University. In the second area, we have continued to study gallium-68 labeled radiopharmaceuticals and have carried out the work to allow gallium-68 labeled macroaggregated albumin to be administered to patients. This was necessary due to the fact that our previous gallium-68 particulate tracer, gallium-68 labeled microspheres could not be prepared due to the fact that the microsphere kit from 3M was removed from the market. In the area of labeled antibodies we have studied indium-111 labeled antibodies in two animal models and compared gallium-68 labeled antibodies with indium and iodine antibodies in one of these models. It appears that gallium-68 labeled antibody fragments may have promise as radiopharmaceuticals

  19. Tumor imaging with monoclonal antibodies

    International Nuclear Information System (INIS)

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

  20. Photonic crystal fiber based antibody detection

    DEFF Research Database (Denmark)

    Duval, A; Lhoutellier, M; Jensen, J B; Hoiby, P E; Missier, V; Pedersen, L H; Hansen, Theis Peter; Bjarklev, Anders Overgaard; Bang, Ole

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

  1. Nutrition Labeling

    Science.gov (United States)

    Metzger, Lloyd E.

    Nutrition labeling regulations differ in countries around the world. The focus of this chapter is on nutrition labeling regulations in the USA, as specified by the Food and Drug Administration (FDA) and the Food Safety and Inspection Service (FSIS) of the United States Department of Agriculture (USDA). A major reason for analyzing the chemical components of foods in the USA is nutrition labeling regulations. Nutrition label information is not only legally required in many countries, but also is of increasing importance to consumers as they focus more on health and wellness.

  2. Imaging tumors with radiolabelled monoclonal antibodies

    International Nuclear Information System (INIS)

    Using a metallic radionuclide, either directly bound to a monoclonal antibody, or to a chelating agent (such as di-ethylenetriamine-pentaacetic acid (DTPA)) conjugated to the antibody, a tumor can be traced rapidly and with high specificity. The labelled antibody is injected into the host. In some cases, a localization of distant metastases is possible, giving an indication of tumor spreading. Detection occurs by photoscanning. (Auth.)

  3. Haptens, conjugates and antibodies for pyrimethanil fungicide

    OpenAIRE

    Mercader Badia, Josep Vicent; Abad Fuentes, Antonio; Abad Somovilla, Antonio; Agulló, Consuelo

    2012-01-01

    [EN] The invention relates to haptens, conjugates and antibodies for pyrimethanil fungicide. In addition, the invention relates to the use of pyrimethanil conjugates as assay antigens or immunogens in order to obtain antibodies of the aforementioned fungicide, and to the use of the labelled derivatives of pyrimethanil as assay antigens. The invention also relates to a pyrimethanil analysis method using the antibodies obtained, at times together with assay antigens which are conjugates or labe...

  4. Radioimmunotherapy with Tenarad, a {sup 131}I-labelled antibody fragment targeting the extra-domain A1 of tenascin-C, in patients with refractory Hodgkin's lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Aloj, Luigi [Istituto Nazionale Tumori ' ' Fondazione G. Pascale' ' - IRCCS, Struttura Complessa di Medicina Nucleare, Napoli (Italy); D' Ambrosio, Laura; Aurilio, Michela; Morisco, Anna; Caraco' , Corradina; Di Gennaro, Francesca; Lastoria, Secondo [Istituto Nazionale Tumori ' ' Fondazione G. Pascale' ' - IRCCS, Struttura Complessa Medicina Nucleare, Napoli (Italy); Frigeri, Ferdinando; Capobianco, Gaetana; Pinto, Antonio [Istituto Nazionale Tumori ' ' Fondazione G. Pascale' ' - IRCCS, Struttura Complessa di Ematologia Oncologica, Napoli (Italy); Giovannoni, Leonardo; Menssen, Hans D. [Philogen, SpA, Siena (Italy); Neri, Dario [Institute of Pharmaceutical Sciences, ETH, Zurich (Switzerland)

    2014-05-15

    The extra-domain A1 of tenascin-C (TC-A1) is highly expressed in the extracellular matrix of tumours and on newly formed blood vessels and is thus a valuable target for radionuclide therapy. Tenarad is a fully human miniantibody or small immunoprotein (SIP, molecular weight 80 kDa) labelled with {sup 131}I that is derived from a TC-A1-binding antibody. Previous phase I/II studies with a similar compound ({sup 131}I-L19SIP) used for radioimmunotherapy (RIT) have shown preliminary efficacy in a variety of cancer types. In this ongoing phase I/II trial, Tenarad was administered to patients with recurrent Hodgkin's lymphoma (HL) refractory to conventional treatments. Eight patients (four men, four women; age range 19 - 41) were enrolled between April 2010 and March 2011. All patients had received a median of three previous lines of chemotherapy (range three to six) and seven had also undergone autologous stem cell transplantation (ASCT) or bone marrow transplantation. In addition, seven patients received external beam radiation. All patients had nodal disease, constitutional B symptoms and some showed extranodal disease in skeletal bone (four patients), lung (three), liver (two) and spleen (one). Baseline assessments included whole-body FDG PET with contrast-enhanced CT and diagnostic Tenarad planar and SPECT studies. Patients were considered eligible to receive a therapeutic dose of Tenarad (2.05 GBq/m{sup 2}) if tumour uptake was more than four times higher than that of muscle. All patients were eligible and received the therapeutic dose of Tenarad. Only one patient developed grade 4 thrombocytopenia and leucocytopenia, requiring hospitalization and therapeutic intervention. All other patients had haematological toxicity of grade 3 or lower, which resolved spontaneously. At the first response assessment (4 - 6 weeks after therapy), one patient showed a complete response, one showed a partial response (PR) and five had disease stabilization (SD). Five patients

  5. Immunogold labels: cell-surface markers in atomic force microscopy

    OpenAIRE

    Putman, Constant A.J.; Grooth, de, B.G.; Hansma, Paul K.; Hulst, van der, R.W.M.; Greve, Jan

    1993-01-01

    The feasibility of using immunogold labels as cell-surface markers in atomic force microscopy is shown in this paper. The atomic force microscope (AFM) was used to image the surface of immunogold-labeled human lymphocytes. The lymphocytes were isolated from whole blood and labeled by an indirect immunolabeling method using the monoclonal antibody anti-CD3 and a secondary antibody (Goat-anti-Mouse) linked to 30 nm colloidal gold particles. Some of the samples were enhanced by silver deposition...

  6. Current state of the art of blood cell labeling

    International Nuclear Information System (INIS)

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

  7. Haptens, conjugates and antibodies for the fungicide cyprodinil

    OpenAIRE

    Mercader Badia, Josep Vicent; Abad Fuentes, Antonio; Abad Somovilla, Antonio; Agulló, Consuelo

    2011-01-01

    [EN] The invention relates to haptens, conjugates, labelled derivatives and antibodies for cyprodinil. Likewise, the present invention also relates to the use of cyprodinil conjugates as test antigens or immunogens for obtaining antibodies of said fungicide, and to the use of the labelled derivatives of cyprodinil as test antigens. Furthermore, the present invention also relates to a method for analysing cyprodinil using the thus obtained antibodies, at times together with the test antigens, ...

  8. Assay for the specificity of monoclonal antibodies in crossed immunoelectrophoresis

    DEFF Research Database (Denmark)

    Skjødt, K; Schou, C; Koch, C

    1984-01-01

    A method is described based on crossed immunoelectrophoresis of a complex antigen mixture in agarose gel followed by incubation of the gel with the monoclonal antibody. The bound monoclonal antibody is detected by the use of a secondary enzyme-labelled antibody. Using this technique we have been ...

  9. Recent developments in blood cell labeling research

    International Nuclear Information System (INIS)

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

  10. Dengue virus growth, purification, and fluorescent labeling.

    Science.gov (United States)

    Zhang, Summer; Chan, Kuan Rong; Tan, Hwee Cheng; Ooi, Eng Eong

    2014-01-01

    The early events of the dengue virus life cycle involve virus binding, internalization, trafficking, and fusion. Fluorescently labeled viruses can be used to visualize these early processes. As dengue virus has 180 identical copies of the envelope protein attached to the membrane surface and is surrounded by a lipid membrane, amine-reactive (Alexa Fluor) or lipophilic (DiD) dyes can be used for virus labeling. These dyes are highly photostable and are ideal for studies involving cellular uptake and endosomal transport. To improve virus labeling efficiency and minimize the nonspecific labeling of nonviral proteins, virus concentration and purification precede fluorescent labeling of dengue viruses. Besides using these viruses for single-particle tracking, DiD-labeled viruses can also be used to distinguish serotype-specific from cross-neutralizing antibodies. Here the details of virus concentration, purification, virus labeling, applications, and hints of troubleshooting are described. PMID:24696327

  11. Phase I clinical trial of the humanized anti-EGF-r antibody H-R3 labeled with 99mTc in patients with tumor of epithelial origin

    International Nuclear Information System (INIS)

    Aim: The aim of this study was to evaluate the biodistribution, internal radiation dosimetry, human anti-mouse antibody (HAMA) response and toxicity of the 99mTc labeled humanized H-R3 MAb using two dose levels. A preliminary analysis of the diagnostic efficacy was also performed. Material and methods: Twenty-five patients with suspicion of epithelial tumors were included on this study. They were divided in two groups. Group I (G-I): Ten patients received intravenous injection of 30mCi-3mg of 99mTc-H-R3; Group II (G-II): 15 patients received 60mCi-6mg of 99mTc-H-R3. Sequential Whole-Body, SPECT and planar images were acquired at different time intervals using a Sophy Camera DS7. Multiple blood and urine samples were collected up to 24 hours after injection. Hematological parameters and adverse effects were evaluated and classified using the WHO classification and HAMA response was also determined. Biodistribution was computed from the scintigraphic images using the Bio Dose software. The absorbed dose for 24 target organs and the equivalent and effective dose (EED, ED) were estimated using the Medical Internal Radiation Dosimetry (MIRD) Committee methodology. Data processing and statistic analyses were performed using the SPSS and microcal Origin v4.0 software packages. Results: Hepatic uptake showed the higher values: 50,7±6,4%ID (Teff = 2,9 hours) and 45.1±6, 25ID (Teff = 3.9 hours) in group I and II, respectively. Maximum uptakes in spleen and heart, for both group, were detected in the first image data-sets (1,6%ID and 2,5%ID respectively) and kidneys reaches the maximum value (1,9%ID) at 3 hours post-injection. The urinary bladder and large intestine had also a significant uptake due to the clearance pattern of this product. The mean urinary excretion was 22.2±7.6% up to 24 hours post-injection. The higher tumor uptake was estimated as 0.026%DI/g in a brain lesion. Liver received the higher absorbed doses (4,90E-02 mGy/MBq in G-I and 4,66E-02 mGy/MBq in G

  12. Studies on radiolabelling of monoclonal antibodies with 99Tcm and other radionuclides for scintigraphy

    International Nuclear Information System (INIS)

    This work performed on the development of radiolabelling of monoclonal antibodies for scintigraphy using direct 99Tcm labelling and other radiolabelling methods of monoclonal antibodies with In-111, Ga-67 or Ru-103

  13. 中性红、吖啶橙及PE标记的LAMP-2抗体在B16F10细胞溶酶体检测中的应用与比较%Application and comparison of neutral red, acridine orange, or PE labeled LAMP-2 antibodies in the detection of lysosomes in B16F10 cells

    Institute of Scientific and Technical Information of China (English)

    翟晓峰; 施文; 李国兴; 孙永强; 赵文静; 钱红燕; 李静; 陈橼; 何向锋

    2012-01-01

    We aimed to investigate the application and value of neutral red, acridine orange, or PE labeled anti-LAMP-2 antibodies in the detection of lysosomes in B16F10 cells. Firstly, we labeled the lysosomes of B16F10 cells with neutral red, acridine orange, and PE labeled anti-LAMP-2 antibodies respectively and detect the labeled lysosomes by optical and fluorescent microscopy. The results showed that the distribution and numbers of lysosomes in B16F10 cells could be clearly observed in optical microscope through the staining of neutral red, and the cytoplasm and lysosome could be stained in green and red respectively by acridine orange, but the quenching of red fluorescence in lysosome was so fast that the detection window was too narrow. The location and numbers of lysosomes in B16F10 cells could be clearly revealed with red fluorescence after the application of PE-labeled anti-LAMP-2 antibody, and the relative location of lysosomes and nucleus could be presented directly along with DAPI staining. In conclusion, the neutral red, acridine orange and PE labeled LAMP-2 antibody staining have their own advantage and characteristics in the detection of lysosomes. The choice of the effective lysosomes detection method should be based on the aim of study.%目的 探讨中性红、吖啶橙及PE标记的LAMP-2抗体在小鼠黑色素瘤B16F10细胞溶酶体检测中的应用与价值.方法 分别用中性红、吖啶橙和PE标记的LAMP-2抗体标记B16F10细胞溶酶体,通过光学和荧光显微镜进行检测.结果 中性红染色法能够在光镜下清晰显示溶酶体在细胞中的分布与数量,并能够反应溶酶体的功能;吖啶橙能够同时将细胞质和溶酶体分别用绿色和红色荧光标示出来,但溶酶体的红色荧光淬灭很快,观测窗口较窄;PE标记的LAMP-2抗体能够将溶酶体在细胞内的位置和数量清晰以红色荧光呈现出来,配合DAPI染色,可以直观显示溶酶体同细胞核

  14. Lectin immuno tests: quantitation and titration of antigens and antibodies using lectin-antibody conjugates

    International Nuclear Information System (INIS)

    The authors have investigated the possibility of using lectin-antibody conjugates as general reagents in immunological procedures requiring a labeled antigen or antibody. Using these conjugates, labeling is achieved through saccharide binding sites of lectins which operate as acceptors for glycoconjugate marker substances added secondarily. Marker substances used in this work were enzymes, radioactively labeled glycoconjugates and erythrocytes, but other markers can also be used. Using the first two markers, antigens and antibodies were determined with accuracy and sensitivity equal to those of conventional enzyme or radioimmunoassays. Using erythrocytes as a marker, a simple erythro-adsorption procedure, possibly followed by hemolysis, has been developed which allowed the titration of antigens and antibodies to be carried out with a sensitivity at least equal to enzyme or radioimmunoassays. (Auth.)

  15. Bispecific antibodies.

    Science.gov (United States)

    Kontermann, Roland E; Brinkmann, Ulrich

    2015-07-01

    Bispecific antibodies (bsAbs) combine specificities of two antibodies and simultaneously address different antigens or epitopes. BsAbs with 'two-target' functionality can interfere with multiple surface receptors or ligands associated, for example with cancer, proliferation or inflammatory processes. BsAbs can also place targets into close proximity, either to support protein complex formation on one cell, or to trigger contacts between cells. Examples of 'forced-connection' functionalities are bsAbs that support protein complexation in the clotting cascade, or tumor-targeted immune cell recruiters and/or activators. Following years of research and development (R&D), the first bsAb was approved in 2009. Another bsAb entered the market in December 2014 and several more are in clinical trials. Here, we describe the potentials of bsAbs to become the next wave of antibody-based therapies, focusing on molecules in clinical development. PMID:25728220

  16. Radiolabeled monoclonal antibodies: a review

    International Nuclear Information System (INIS)

    Since the description by Kohler and Milstein 1975 of their technique for producing monoclonal antibodies of predefined specificity, it has become a mainstay in most laboratories that utilize immunochemical techniques to study problems in basic, applied or clinical research. Paradoxically, the very success of monoclonal antibodies has generated a literature which is now so vast and scattered that it has become difficult to obtain a perspective. This brief review represents the distillation of many publications relating to the production and use of monoclonaal antibodies as radiopharmaceuticals. Significant advances were made possible in the last few years by combined developments in the fields of tumor-associated antigens and of monoclonal antibodies. In fact monoclonal antibodies against some well defined tumor-associated antigens, has led to significantly greater practical possibilities for producing highly specific radiolabeled antibodies as radiopharmaceuticals for diagnosis and therapy of human tumors. One of the main requirements of this methodology is the availability of stable radiopharmaceutical reagents which after labeling in vivo injection retain the capacity of specific interaction with the defined antigen and their molecular integrity. Since injection into human is the objetive of this kind of study all the specifications of radiopharmaceutical have to be fulfilled e.g. sterility, apirogenicity and absence of toxicity. (author)

  17. Radioimmunoguided surgery using monoclonal antibody

    International Nuclear Information System (INIS)

    The potential proficiency of radioimmunoguided surgery in the intraoperative detection of tumors was assessed using labeled monoclonal antibody B72.3 in 66 patients with tissue-proved tumor. Monoclonal antibody B72.3 was injected 5 to 42 days preoperatively, and the hand-held gamma-detecting probe was used intraoperatively to detect the presence of tumor. Intraoperative probe counts of less than 20 every 2 seconds, or tumor-to-adjacent normal tissue ratios less than 2:1 were considered negative (system failure). Positive probe counts were detected in 5 of 6 patients with primary colon cancer (83 percent), in 31 of 39 patients with recurrent colon cancer (79 percent), in 4 of 5 patients with gastric cancer (80 percent), in 3 of 8 patients with breast cancer (37.5 percent), and in 4 of 8 patients with ovarian cancer (50 percent) undergoing second-look procedures. Additional patients in each group were scored as borderline positive. Overall, radioimmunoguided surgery using B72.3 identified tumors in 47 patients (71.2 percent), bordered on positive in 6 patients (9.1 percent), and failed to identify tumor in 13 patients (19.7 percent). Improved selection of patients for antigen-positive tumors, the use of higher affinity second-generation antibodies, alternate routes of antibody administration, alternate radionuclides, and more sophisticatedly bioengineered antibodies and antibody combinations should all lead to improvements in radioimmunoguided surgery

  18. Immunoglobulin Classification Using the Colored Antibody Graph.

    Science.gov (United States)

    Bonissone, Stefano R; Pevzner, Pavel A

    2016-06-01

    The somatic recombination of V, D, and J gene segments in B-cells introduces a great deal of diversity, and divergence from reference segments. Many recent studies of antibodies focus on the population of antibody transcripts that show which V, D, and J gene segments have been favored for a particular antigen, a repertoire. To properly describe the antibody repertoire, each antibody must be labeled by its constituting V, D, and J gene segment, a task made difficult by somatic recombination and hypermutation events. While previous approaches to repertoire analysis were based on sequential alignments, we describe a new de Bruijn graph-based algorithm to perform VDJ labeling and benchmark its performance. PMID:27149636

  19. Radiolabelling of monoclonal antibodies for radiotherapy. Thailand

    International Nuclear Information System (INIS)

    Nuclear medicine is now playing a great role not only in diagnostic application but also in therapy of cancer patients. Under the concept of targeted radiotherapy, a number of radiopharmaceuticals based on radiolabelled biomolecules had been evaluated for treatment of cancer by many investigators. Of these, monoclonal antibodies and some small specific peptides labelled with beta emitting radiometals such as Sm-153, Re-186, Re-188 or Y-90, are being introduced into clinical trials. The objective of this project is to develop laboratory procedures to label monoclonal antibodies, peptide or other proteins with beta emitting radionuclides to prepare radiopharmaceuticals for therapeutic purpose

  20. Radiolabelling of monoclonal antibodies for radiotherapy

    International Nuclear Information System (INIS)

    Nuclear medicine is now playing a great role not only in diagnostic application but also in therapy of cancer patients. Under the concept of targeted radiotherapy, a number of radiopharmaceuticals based on radiolabelled biomolecules had been evaluated for treatment of cancer by many investigators. Of these, monoclonal antibodies and some small specific peptides labelled with beta emitting radiometals such as Sm-153, Re-186, Re-188 or Y-90, are being introduced into clinical trials. The objective of this project is to develop laboratory procedures to label monoclonal antibodies, peptide or other proteins with beta emitting radionuclides to prepare radiopharmaceuticals for therapeutic purpose

  1. Food labels

    DEFF Research Database (Denmark)

    Selsøe Sørensen, Henrik; Clement, Jesper; Gabrielsen, Gorm

    2012-01-01

    The food industry develops tasty and healthy food but fails to deliver the message to all consumers. The consumers’ background knowledge is essential for how they find and decode relevant elements in the cocktail of signs which fight for attention on food labels. In this exploratory study, we find...... evidence for dividing consumers into two profiles: one relying on general food knowledge and another using knowledge related to signpost labels. In a combined eyetracking and questionnaire survey we analyse the influence of background knowledge and identify different patterns of visual attention for the...... two consumer profiles. This underlines the complexity in choosing and designing the ‘right’ elements for a food package that consumers actually look at and are able to make rational use of. In spite of any regulation of food information provided by authorities, consumers will still be confronted with...

  2. Environmental Labeling

    OpenAIRE

    Andrea Podhorsky

    2009-01-01

    This paper studies how information disclosed by voluntary environmental labels creates incentives for firms to invest in environmentally-friendly production technologies. I develop a model with differentiated products and imperfectly-informed consumers. Consumers care about the environmental characteristics of goods (for example, how they were produced), but cannot directly observe these product characteristics. Firms differ in their abilities to develop "clean" technologies, but have no ince...

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

    Science.gov (United States)

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

    2015-01-01

    Antibodies against cell surface antigens may be internalized through their specific interactions with these proteins and in some cases may induce or perturb antigen internalization. The anti-cancer efficacy of antibody-drug conjugates is thought to rely on their uptake by cancer cells expressing the surface antigen. Numerous techniques, including microscopy and flow cytometry, have been used to identify antibodies with desired cellular uptake rates. To enable quantitative measurements of internalization of labeled antibodies, an assay based on internalized and quenched fluorescence was developed. For this approach, we generated novel anti-Alexa Fluor monoclonal antibodies (mAbs) that effectively and specifically quench cell surface-bound Alexa Fluor 488 or Alexa Fluor 594 fluorescence. Utilizing Alexa Fluor-labeled mAbs against the EphA2 receptor tyrosine kinase, we showed that the anti-Alexa Fluor reagents could be used to monitor internalization quantitatively over time. The anti-Alexa Fluor mAbs were also validated in a proof of concept dual-label internalization assay with simultaneous exposure of cells to two different mAbs. Importantly, the unique anti-Alexa Fluor mAbs described here may also enable other single- and dual-label experiments, including label detection and signal enhancement in macromolecules, trafficking of proteins and microorganisms, and cell migration and morphology. PMID:25894652

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

    Directory of Open Access Journals (Sweden)

    Sindy Liao-Chan

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

  5. Development of radiolabelling techniques of anti-CEA monoclonal antibody

    International Nuclear Information System (INIS)

    The purpose of this work was to label monoclonal and polyclonal antibodies with 99Tcm 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 99Tcm 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 99Tcm added as glucoheptonate complex. The properties of 99Tcm when labelled with monoclonal and polyclonal antibodies by different methods were assessed by in vitro and in vivo studies

  6. Clinical application of a new antimyosin antibody

    International Nuclear Information System (INIS)

    A mouse monoclonal antibody, 3-48 (Rougier Bio-Tech Ltd, Montreal) which recognizes the alpha and beta heavy chains of human atrial and ventricular myosin, and the beta heavy chain of human slow skeletal muscle, has recently been developed. In the rat isoproterenol-induced infarction model and the canine model of selective obstruction of a coronary artery, the antibody was shown to be specifically localized to the necrotic myocardium. A selected group of patients with known infarction was imaged with the 111indium labeled F(ab')2 protion of this antibody in a pre-clinical feasibility study, and the results therefrom are reported in this communication. (orig.)

  7. Measurement of tumour reactive antibody and antibody conjugate by competition, quantitated by flow cytofluorimetry.

    Science.gov (United States)

    Robins, R A; Laxton, R R; Garnett, M; Price, M R; Baldwin, R W

    1986-06-24

    Binding of unlabelled monoclonal antibody preparations has been assessed by competition at saturation with fluorochrome labelled homologous antibody for binding to antigen bearing target cells. The extent of competition was measured by quantitative flow cytofluorimetry, and simple mathematical procedures have been developed to allow the interpretation of competition data in terms of antibody binding activity. In the system studied, non-specific (non-competitive) fluorescence was minimal, but an iterative method to calculate its contribution to the measured signal is given. This approach has the advantage that the antibody preparation to be tested does not need to be labelled or modified; this is particularly important when evaluating the binding activity of therapeutic antibody conjugates. Comparison with a well characterized standard antibody preparation provides a rapid, sensitive and accurate quality control procedure. This test is also simple to perform, requiring only the mixing of labelled and unlabelled antibodies with target cells, a single incubation, followed by analysis without washing of the target cells. PMID:2424997

  8. The labelling of antibody anti-PBP2a with {sup 99m}Tc; Estudo de marcacao do anticorpo monoclonal anti-PBP2a com {sup 99m}Tc

    Energy Technology Data Exchange (ETDEWEB)

    Mororo, Janio da Silva

    2012-07-01

    Staphylococcus aureus is a major cause of life-threatening infections such as bacteraemia and endocarditis. Unfortunately, many strains of this bacterial species have become resistant to certain antibiotics, including methicillin and amoxicillin. These strains are known as methicillin-resistant S. aureus (MRSA). The penicillin binding protein 2a (PBP2a) is the enzyme responsible for conferring resistance p-lactams antibiotics for MRSA, being one promising molecule for therapy with mAb. However, besides the therapy, the methods of diagnosis are also inefficient because the diagnosis currently takes several days to produce a reliable result. Taking into account, the objective of this research was radiolabeling one anti-PBP2a mAb developed by Bio-Manguinhos/FioCruz-RJ, utilizing {sup 99m}Tc, for in situ diagnostic of the infectious caused by MRSA. First, anti-PBP2a mAb was reduced utilizing 2-mecaptoethanol (2-ME) for generate sulphydryl groups (-SH) and after to be labeled with {sup 99m}Tc. In this work, were utilized two techniques of direct method: Method 1, using tartrate and gentisic acid reagents, acting like transchelant and stabilizer agents, respectively; and Method 2, using one commercial kit of MDP. Besides the radiolabeling, the mAb reduced and mAb labeled with {sup 99m}Tc were submitted to immunoreactivity analysis, with SDS-PAGE non-reducing, Immunoblotting, ELISA and neutralization assay in vitro methods. The quantity produced of sulphydryl groups by mAb was satisfactory, approximately 5 per mAb, utilizing 6.500:1 of 2-ME:mAb molar ratio. The better labeling method was Method 2, with labeling yield of 73.5%, and showed a good stability after 2 hours (73.2%). The better formulation was: 0.5 mg of mAb anti- PBP2a, 10 {mu}U of MDP kit, after resuspended with 5 mL of saline, and 75.48 MBq (2.04 mCi) of {sup 99m}Tc, reacting by 15 minutes. The labeled mAb maintained the immunoreactivity, utilizing immunologic and in vitro experiments. (author)

  9. The haemolytic antibody isotope release (HAIR) assay; an efficient alternative technique to conventional plaque assays

    International Nuclear Information System (INIS)

    The haemolytic antibody isotope release (HAIR) assay quantitates antibody production by splenic antibody-producing cells by lysis of chromium-51-labelled sheep red blood cells. The amount of antibody quantitated by the HAIR assay directly correlates with the number of antibody-producing cells measured by a conventional plaque assay. The HAIR assay is an easy, sensitive, and reproducible technique that is especially useful when large numbers of animals are required for testing. (author)

  10. Biomolecule labelling by 186 Re

    International Nuclear Information System (INIS)

    The aim of this study is to develop and improve the existing radiolabelling techniques of peptides and monoclonal antibodies with 186 Re and 188 Re as potential agents for cancer targeted radiotherapy. We selected the following methods and techniques for direct labelling of peptides and monoclonal antibody: 1. Prereduction of -S-S- bridges of biomolecule to sulfhydryls using reducing agents: ascorbic acid, cysteine, active hydrogen, 2,3 dimercaptopropanol. The prereduction reactions are controlled by massic ratios of reduction agents/biomolecule, pH, temperature and time of incubation; 2. Reduction of 186 Re O4- stannous chloride in acid and alkaline pH; 3. Coupling reaction of 186 Re (red) with the biomolecule controlled by the time and temperature of incubation, the influence of pH regarding the binding of 186 Re to the biomolecules. The quality control was effected by chromatography techniques (paper and elution gel chromatography) on labeled biomolecule before and after purification. The elution gel chromatography was spectrophotometricaly monitored at 280 nm. In the same time the radioactivity of samples was measured using a gamma counter. All the results confirm in vitro stability of labeled biomolecule. The biological evaluation studies regarding accumulation and biological affinity will be controlled by scintigraphy method. Biodistribution studies will be effected to Walker tumor bearing animals at 4 and 24 hours after injections. (authors)

  11. Development of labelled biomolecules for targeted radiotherapy

    International Nuclear Information System (INIS)

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

  12. Preparation and use of radiolabelled specific helminth antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Movsesijan, M.; Jovanovic, B.; Borojevic, D.; Petrovic, M. (Institut za Primeni Nuklearne Energije u Poljoprivedri, Veterinarstvu i Sumarstvu, Zemun (Yugoslavia))

    1983-05-01

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

  13. The preparation and use of radiolabelled specific helminth antibodies

    International Nuclear Information System (INIS)

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

  14. Bone marrow dosimetry for monoclonal antibody therapy

    International Nuclear Information System (INIS)

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

  15. Monoclonal antibodies

    International Nuclear Information System (INIS)

    Monoclonal antibodies (MAbs) are antibodies having single specificity for a given antigen site (epitope). The development of hybridoma technology and the relative ease by which MAbs can be prepared has revolutionized many aspects of serological applications in diagnosis and differentiation of disease producing agents. The property of monospecificity offers advantages in diagnostic applications over polyclonal sera in that tests can be defined exactly with regard to the antigen detected and the affinity of reaction between the given antigenic site and the monoclonal reagent. In addition, MAbs offer better possibilities for test standardization, because the same reagent can be used in different laboratories. Such an MAb can be supplied by a central laboratory or 'grown' from hybridoma cells, ensuring that the resultant product is identical from laboratory to laboratory and that the part of the test involving the MAb reaction is the same. The methodologies for inoculation regimes, mice, cloning methods, selection of fusion partners, etc., have been validated extensively in developed country laboratories. The decision to establish a MAb production facility must be examined on a strict cost-benefit basis, since it is still expensive to produce a product. There are many MAbs available that should be sought to allow exploitation in developing tests. If a production facility is envisaged, it should produce reagents for national needs, i.e. there should be a clear problem oriented approach whereby exact needs are defined. In the field of veterinary applications, MAbs are the central reagent in many immunoassays based on the enzyme linked immunosorbent assay (ELISA). The development of specific tests for diagnosing diseases is dominated by MAbs and has been fuelled by a strong research base, mainly in developed countries allied to developing countries through the study of related diseases. Thus, there are very many assays dependent on MAbs, some of which form the basis of

  16. An Ultrasensitive Electrochemiluminescence Immunoassay for Carbohydrate Antigen 19-9 in Serum Based on Antibody Labeled Fe3O4 Nanoparticles as Capture Probes and Graphene/CdTe Quantum Dot Bionanoconjugates as Signal Amplifiers

    Directory of Open Access Journals (Sweden)

    Ning Gan

    2013-05-01

    Full Text Available The CdTe quantum dots (QDs, graphene nanocomposite (CdTe-G and dextran–Fe3O4 magnetic nanoparticles have been synthesized for developing an ultrasensitive electrochemiluminescence (ECL immunoassay for Carcinoembryonic antigen 19-9 (CA 19-9 in serums. Firstly, the capture probes (CA 19-9 Ab1/Fe3O4 for enriching CA 19-9 were synthesized by immobilizing the CA 19-9’s first antibody (CA 19-9 Ab1 on magnetic nanoparticles (dextran-Fe3O4. Secondly, the signal probes (CA 19-9 Ab2/CdTe-G, which can emit an ECL signal, were formed by attaching the secondary CA 19-9 antibody (CA 19-9 Ab2 to the surface of the CdTe-G. Thirdly, the above two probes were used for conjugating with a serial of CA 19-9 concentrations. Graphene can immobilize dozens of CdTe QDs on their surface, which can emit stronger ECL intensity than CdTe QDs. Based on the amplified signal, ultrasensitive antigen detection can be realized. Under the optimal conditions, the ECL signal depended linearly on the logarithm of CA 19-9 concentration from 0.005 to 100 pg/mL, and the detection limit was 0.002 pg/mL. Finally, five samples of human serum were tested, and the results were compared with a time-resolved fluorescence assay (TRFA. The novel immunoassay provides a stable, specific and highly sensitive immunoassay protocol for tumor marker detection at very low levels, which can be applied in early diagnosis of tumor.

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

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

  19. The study on the use of fragmented antibody for the development of therapeutic radiopharmaceutical

    International Nuclear Information System (INIS)

    This project was designed to develop the therapeutic radiopharmaceuticals for therapy and diagnosis of cancer using fragmented antibodies. The major activities to be carried out are as follows: - exploration of the key angiogenic factors involved in cancer, - development of radiolabeled-compounds using antibody fragments for minimal toxicity - In vitro/vivo investigation on the targeting ability of RI labeled antibody fragment

  20. Neuronal uptake of anti-Hu antibody, but not anti-Ri antibody, leads to cell death in brain slice cultures

    OpenAIRE

    Greenlee, John E.; Clawson, Susan A.; Kenneth E Hill; Wood, Blair; Clardy, Stacey L.; Tsunoda, Ikuo; Jaskowski, Troy D; Carlson, Noel G.

    2014-01-01

    Background Anti-Hu and anti-Ri antibodies are paraneoplastic immunoglobulin (Ig)G autoantibodies which recognize cytoplasmic and nuclear antigens present in all neurons. Although both antibodies produce similar immunohistological labeling, they recognize different neuronal proteins. Both antibodies are associated with syndromes of central nervous system dysfunction. However, the neurological deficits associated with anti-Hu antibody are associated with neuronal death and are usually irreversi...

  1. Monoclonal antibodies.

    Science.gov (United States)

    2009-01-01

    The ability to produce and exploit monoclonal antibodies (mAbs) has revolutionized many areas of biological sciences. The unique property of an mAb is that it is a single species of immunoglobulin (IG) molecule. This means that the specificity of the interaction of the paratopes on the IG, with the epitopes on an antigenic target, is the same on every molecule. This property can be used to great benefit in immunoassays to provide tests of defined specificity and sensitivity, which improve the possibilities of standardization. The performance of assays can often be determined relating the actual weight of antibody (hence the number of molecules) to the activity. Often the production of an mAb against a specific epitope is the only way that biological entities can be differentiated. This chapter outlines the areas involving the development of assays based on mAbs. The problems involved address include the physical aspects of mAbs and how they may affect assay design and also the implications of results based on monospecific reagents. Often these are not fully understood, leading to assays that are less than satisfactory, which does not justify the relatively high cost of preparing and screening of mAbs. There are many textbooks and reviews dealing with the preparation of mAbs, the principles involved, and various purification and manipulative methods for the preparation of fragments and conjugation. There has been little general information attempting to summarize the best approaches to assay design using mAbs. Much time can be wasted through bad planning, and this is particularly relevant to mAbs. A proper understanding of some basic principles is essential. It is beyond the scope of this chapter to discuss all aspects, but major areas are highlighted. PMID:19219589

  2. Radioimmunoimaging of 131I-anti human colon carcinoma monoclonal antibodies in nude mice with tumor xenografts

    International Nuclear Information System (INIS)

    The paired labeled antibodies, 131-labeled anti-human colon carcinoma monoclonal antibody 2C10 and 125I-labeled mice IgG, were used in the radioimmunolocalization study in nude mice with human colon carcinoma xenograft. The antibodies were radioiodinated with Iodogen method, and the incroporation efficiency and immune activity of the labeled antibodies were satisfactory. 96 hours after injection of the antibodies, good tumor localization was observed. Tumor/L. intestinal ratio was 7.08, tumor/S. intestinal 6.02, tumor/muscle 7.53, tumor/blood 1.10. Tumor imaging with camera was clear. The entrance of the antibodies into tumor tissues is a slow passive process and the accumulation of the antibodies in tumor is a combined result of specific immune reactivity and nonspecific deposition

  3. Quantitative localization microscopy: effects of photophysics and labeling stoichiometry.

    Directory of Open Access Journals (Sweden)

    Robert P J Nieuwenhuizen

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

  4. Monoclonal Antibodies Attached to Carbon Nanotube Transistors for Paclitaxel Detection

    Science.gov (United States)

    Lee, Wonbae; Lau, Calvin; Richardson, Mark; Rajapakse, Arith; Weiss, Gregory; Collins, Philip; UCI, Molecular Biology; Biochemistry Collaboration; UCI, Departments of Physics; Astronomy Collaboration

    Paclitaxel is a naturally-occurring pharmaceutical used in numerous cancer treatments, despite its toxic side effects. Partial inhibition of this toxicity has been demonstrated using weakly interacting monoclonal antibodies (3C6 and 8A10), but accurate monitoring of antibody and paclitaxel concentrations remains challenging. Here, single-molecule studies of the kinetics of antibody-paclitaxel interactions have been performed using single-walled carbon nanotube field-effect transistors. The devices were sensitized with single antibody attachments to record the single-molecule binding dynamics of paclitaxel. This label-free technique recorded a range of dynamic interactions between the antibody and paclitaxel, and it provided sensitive paclitaxel detection for pM to nM concentrations. Measurements with two different antibodies suggest ways of extending this working range and uncovering the mechanistic differences among different antibodies.

  5. Clinical experience in humans with radiolabeled antibody for tumor detection

    International Nuclear Information System (INIS)

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

  6. Biophysical characterization of a model antibody drug conjugate.

    Science.gov (United States)

    Arakawa, Tsutomu; Kurosawa, Yasunori; Storms, Michael; Maruyama, Toshiaki; Okumura, C J; Maluf, Nasib Karl

    2016-01-01

    Antibody drug conjugates (ADC) are important next-generation biopharmaceuticals and thus require stringent structure characterization as is the case for monoclonal antibodies. We have tested several biophysical techniques, i.e., circular dichroism, analytical ultracentrifugation, differential scanning calorimetry and fluorescence spectroscopy, to characterize a fluorescein-labeled monoclonal antibody as a model ADC. These techniques indicated possible small structure and stability changes by the conjugation, while largely retaining the tertiary structure of the antibody, consistent with unaltered biological activities. Thus, the above biophysical techniques are effective at detecting changes in the structural properties of ADC. PMID:27534450

  7. Comparative biodistribution of indium- and yttrium-labeled B3 monoclonal antibody conjugated to either 2-(p-SCN-Bz)-6-methyl-DTPA (1B4M-DTPA) or 2-(p-SCN-Bz)-1,4,7,10-tetraazacyclododecane tetraacetic acid (2B-DOTA)

    International Nuclear Information System (INIS)

    The biodistribution of indium-111/yttrium-88-labeled B3 monoclonal antibody, a murine IgGlk, was evaluated in non-tumor-bearing mice. B3 was conjugated to either 2-(p-SCN-Bz)-6-methyl-DTPA (1B4M) or 2-(p-SCN-Bz)-1,4,7,10 tetraazacyclododecane tetra-acetic acid (2B-DOTA) and labeled with 111In at 1.4-2.4 mCi/mg and 88Y at 0.1-0.3 mCi/mg. Non-tumor-bearing nude mice were co-injected i.v. with 5-10 μCi/4-10 μg of 111In/88Y-labeled B3 conjugates and sacrificed at 6 h and daily up to 168 h post-injection. Mice injected with 111In/88Y-(1B4M)-B3 showed a similar biodistribution of the two radiolabels in all tissues except the bones, where significantly higher accretion of 88Y than 111In was observed, with 2.8% ± 0.2% vs 1.3% ± 0.16% ID/g in the femur at 168 h, respectively (P111In/88Y-(DOTA)-B3 conjugate showed significantly higher accumulation of 111In than 88Y in most tissues, including the bones, with 2.0% ± 0.1% vs 1.2% ± 0.09% ID/g in the femur at 168 h, respectively (P111In/88Y-(1B4M)-B3 and 0.84, 1.23, 1.56, and 1.31 for 111In/88Y-(DOTA)-B3, respectively, ratios ∼ 1 were observed between 111In-(1B4M)-B3 and 88Y-(DOTA)-B3. In summary, while neither 1B4M nor DOTA was equally stable for 111In and 88Y, the fate of 88Y-(DOTA)-B3 could be closely traced by that of 111In-(1B4M)-B3. (orig.)

  8. Preparation of radiopharmaceuticals labeled with metal radionuclides

    International Nuclear Information System (INIS)

    We recently developed a useful zinc-62/copper-62 generator and are presently evaluating copper-62 radiopharmaceuticals for clinical studies. While developing these copper-62 radiopharmaceuticals, in collaboration with the University of Missouri Research Reactor, Columbia we have also explored copper-64 radiopharmaceuticals. The PET images we obtained with copper-64 tracers were of such high quality that we have developed and evaluated copper-64 labeled antibodies for PET imaging. The major research activities described herein include: the development and assessment of gallium-68 radiopharmaceuticals; the development and evaluation of a new zinc-62/copper-62 generator and the assessment of copper-62 radiopharmaceuticals; mechanistic studies on proteins labeled with metal radionuclides

  9. Preparation of radiopharmaceuticals labeled with metal radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Welch, M.J.

    1992-06-01

    We recently developed a useful zinc-62/copper-62 generator and are presently evaluating copper-62 radiopharmaceuticals for clinical studies. While developing these copper-62 radiopharmaceuticals, in collaboration with the University of Missouri Research Reactor, Columbia we have also explored copper-64 radiopharmaceuticals. The PET images we obtained with copper-64 tracers were of such high quality that we have developed and evaluated copper-64 labeled antibodies for PET imaging. The major research activities described herein include: the development and assessment of gallium-68 radiopharmaceuticals; the development and evaluation of a new zinc-62/copper-62 generator and the assessment of copper-62 radiopharmaceuticals; mechanistic studies on proteins labeled with metal radionuclides.

  10. Issues in Data Labelling

    NARCIS (Netherlands)

    Cowie, Roddy; Cox, Cate; Martin, Jeam-Claude; Batliner, Anton; Heylen, Dirk; Karpouzis, Kostas; Cowie, Roddy; Pelachaud, Catherine; Petta, Paolo

    2011-01-01

    Labelling emotion databases is not a purely technical matter. It is bound up with theoretical issues. Different issues affect labelling of emotional content, labelling of the signs that convey emotion, and labelling of the relevant context. Linked to these are representational issues, involving time

  11. Effect of chelating agents on the distribution of monoclonal antibodies in mice

    International Nuclear Information System (INIS)

    The potential for altering the biodistribution of radiolabel from gallium- and indium-labeled mouse monoclonal antibodies was investigated in mice using metal chelating agents. The chelating agents used were desferrioxamine (DFO), diethylenetriaminepentaacetic acid (DTPA), ethylenediamine-di (O-hydroxyphenylacetic acid) (EDHPA), and 2,2' dipyridyl (DIPY). The mouse monoclonal antibody LICR-LON-M8 was labeled with 111In after conjugation to DTPA, and with 67Ga after conjugation to DFO. All the chelating agents except DIPY altered the biodistribution of [67Ga]citrate and [111In]citrate but did not affect the 48-hr tissue uptake of label from [111In]DTPA-M8 or [67Ga]DFO-M8, confirming the in vivo stability of the antibody conjugates. Label fixed in the tissues was inaccessible to the chelating agents, indicating that they will not be suitable for reducing the high background liver radioactivity in patients undergoing scanning with indium-labeled antibodies

  12. Radiation safety issues related to radiolabeled antibodies

    International Nuclear Information System (INIS)

    Techniques related to the use of radiolabeled antibodies in humans are reviewed and evaluated in this report. It is intended as an informational resource for the US Nuclear Regulatory Commission (NRC) and NRC licensees. Descriptions of techniques and health and safety issues are provided. Principal methods for labeling antibodies are summarized to help identify related radiation safety problems in the preparation of dosages for administration to patients. The descriptions are derived from an extensive literature review and consultations with experts in the field. A glossary of terms and acronyms is also included. An assessment was made of the extent of the involvement of organizations (other than the NRC) with safety issues related to radiolabeled antibodies, in order to identify regulatory issues which require attention. Federal regulations and guides were also reviewed for their relevance. A few (but significant) differences between the use of common radiopharmaceuticals and radiolabeled antibodies were observed. The clearance rate of whole, radiolabeled immunoglobulin is somewhat slower than common radiopharmaceuticals, and new methods of administration are being used. New nuclides are being used or considered (e.g., Re-186 and At-211) for labeling antibodies. Some of these nuclides present new dosimetry, instrument calibration, and patient management problems. Subjects related to radiation safety that require additional research are identified. 149 refs., 3 figs., 20 tabs

  13. Radiometallating antibodies and biologically active peptides

    International Nuclear Information System (INIS)

    We have developed methods to radiolabel large molecules, using porphyrins as bifunctional chelating agents for radiometals. The porphyrins are substituted with an N-benzyl group to activate them for radiometallation under mild reaction conditions. Porphyrins that have on functional group for covalent attachment to other molecules cannot cause crosslinking. We have examined the labeling chemistry for antibodies, and we have also developed methods to label smaller biologically active molecules, such as autoantigenic peptides. The autoantigenic peptides, fragments of the acetylcholine receptor, are under investigation for myasthenia gravis research. The methods of covalent attachment of these bifunctional chelating agents to large molecules and the radiometallation chemistry will be discussed

  14. Development of 211At Chemistry for Labelling Biomolecules

    International Nuclear Information System (INIS)

    Our studies have demonstrated that high recovery of 211At can be obtained using a “wet chemistry” approach to isolation from the bismuth target. We have also demonstrated that direct labelling of antibody-B10 conjugates with 211At can be performed in high yields, and that the astatinated antibodies are stable to in vivo deastatination. While these results will allow us to enter clinical studies with 211At-labelled antibodies, the chemistry associated with 211At is not fully understood. Therefore, it is important that many more basic studies to be conducted with 211At, so the optimal labelling reagent for each type of disease-targeting agent becomes apparent

  15. Succesful labelling schemes

    DEFF Research Database (Denmark)

    Juhl, Hans Jørn; Stacey, Julia

    2001-01-01

    It is usual practice to evaluate the success of a labelling scheme by looking at the awareness percentage, but in many cases this is not sufficient. The awareness percentage gives no indication of which of the consumer segments that are aware of and use labelling schemes and which do not. In the...... spring of 2001 MAPP carried out an extensive consumer study with special emphasis on the Nordic environmentally friendly label 'the swan'. The purpose was to find out how much consumers actually know and use various labelling schemes. 869 households were contacted and asked to fill in a questionnaire....... 664 households returned a completed questionnaire. There were five answering categories for each label in the questionnaire: * have not seen the label before. * I have seen the label before but I do not know the precise contents of the labelling scheme. * I have seen the label before, I do not know...

  16. Antibodies and Selection of Monoclonal Antibodies.

    Science.gov (United States)

    Hanack, Katja; Messerschmidt, Katrin; Listek, Martin

    2016-01-01

    Monoclonal antibodies are universal binding molecules with a high specificity for their target and are indispensable tools in research, diagnostics and therapy. The biotechnological generation of monoclonal antibodies was enabled by the hybridoma technology published in 1975 by Köhler and Milstein. Today monoclonal antibodies are used in a variety of applications as flow cytometry, magnetic cell sorting, immunoassays or therapeutic approaches. First step of the generation process is the immunization of the organism with appropriate antigen. After a positive immune response the spleen cells are isolated and fused with myeloma cells in order to generate stable, long-living antibody-producing cell lines - hybridoma cells. In the subsequent identification step the culture supernatants of all hybridoma cells are screened weekly for the production of the antibody of interest. Hybridoma cells producing the antibody of interest are cloned by limited dilution till a monoclonal hybridoma is found. This is a very time-consuming and laborious process and therefore different selection strategies were developed since 1975 in order to facilitate the generation of monoclonal antibodies. Apart from common automation of pipetting processes and ELISA testing there are some promising approaches to select the right monoclonal antibody very early in the process to reduce time and effort of the generation. In this chapter different selection strategies for antibody-producing hybridoma cells are presented and analysed regarding to their benefits compared to conventional limited dilution technology. PMID:27236550

  17. Production and Characterization of Monoclonal Antibodies of Shrimp White Spot Syndrome Virus Envelope Protein VP28

    Institute of Scientific and Technical Information of China (English)

    Wan-gang GU; Jun-fa YUAN; Ge-lin XU; Li-juan LI; Ni LIU; Cong ZHANG; Jian-hong ZHANG; Zheng-li SHI

    2007-01-01

    BALB/c mice were immunized with purified White spot syndrome virus (WSSV).Six monoclonal antibody cell lines were selected by ELISA with VP28 protein expressed in E.coll in vitro neutralization experiments showed that 4 of them could inhibit the virus infection in crayfish.Westernblot suggested that all these monoclonal antibodies were against the conformational structure of VP28.The monoclonal antibody 7B4 was labeled with colloidal gold particles and used to locate the VP28 on virus envelope by immunogold labeling.These monoclonal antibodies could be used to develop immunological diagnosis methods for WSSV infection.

  18. Synthesizing labeled compounds

    International Nuclear Information System (INIS)

    A metabolic study is presented of the chemical reactions provided by isotopic labeling and NMR spectroscopy. Synthesis of 13C-labeled D-glucose, a 6-carbon sugar, involves adding a labeled nitrile group to the 5-carbon sugar D-arabinose by reaction with labeled hydrogen cyanide. The product of this reaction is then reduced and hydrolyzed to a mixture of the labeled sugars. The two sugars are separated by absorption chromotography. The synthesis of 13C-labeled L-tyrosine, an amino acid, is also presented

  19. Localization of melanoma with radiolabelled monoclonal antibody fragments and iodoamphetamine

    Energy Technology Data Exchange (ETDEWEB)

    Liewendahl, K.; Kairento, A.L.; Lindroth, L.; Pyroenen, S.; Franssila, K.; Virkkunen, P.; Asko-Seljavaara, S.; Launes, J.

    1986-10-01

    In two melanoma patients, metastases accumulated both /sup 99m/Tc-labelled monoclonal anti-tumor F(ab')/sub 2/ fragments and N-isopropyl-p-(/sup 123/I)-iodoamphetamine. Small metastatic deposits were localized only by labelled antibody, for which a higher target-to-nontarget ratio was observed than for radioiodoamphetamine, indicating that immunoscintigraphy may be the more sensitive method. In these two patients positive immunohistochemical staining for the antibody used was observed, whereas in a third patient, with no concentration of labelled antibody, the staining result was negative showing the specificity of the immunoscintigraphy findings. It is possible that the accumulation of radio-iodoamphetamine is due to binding to melanin but this is not certain as tissue samples from one of the two patients with positive scintigrams did not contain stainable melanin.

  20. Monoclonal antibodies to the human insulin receptor that activate glucose transport but not insulin receptor kinase activity.

    OpenAIRE

    Forsayeth, J R; Caro, J F; Sinha, M K; Maddux, B A; Goldfine, I D

    1987-01-01

    Three mouse monoclonal antibodies were produced that reacted with the alpha subunit of the human insulin receptor. All three both immunoprecipitated 125I-labeled insulin receptors from IM-9 lymphocytes and competitively inhibited 125I-labeled insulin binding to its receptor. Unlike insulin, the antibodies failed to stimulate receptor autophosphorylation in both intact IM-9 lymphocytes and purified human placental insulin receptors. Moreover, unlike insulin, the antibodies failed to stimulate ...

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

    International Nuclear Information System (INIS)

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

  2. Antibody Discovery via Multiplexed Single Cell Characterization

    OpenAIRE

    Harriman, William D.; Collarini, Ellen J.; Sperinde, Gizette V.; Strandh, Magnus; Fatholahi, Marjan M.; Dutta, April; Lee, Yunji; Mettler, Shelley E.; Keyt, Bruce A.; Ellsworth, Stote L.; Kauvar, Lawrence M.

    2008-01-01

    The secreted immunoglobulin footprint of single hybridoma cells, containing ~10 fg of antibody purified in situ, has been probed for 9 properties concurrently by use of detection labels comprising 280 nm combinatorially colored fluorescent latex beads functionalized with proteins. Specificity of each individual hybridoma cell’s product has thereby been assessed in a primary screen. Varying the density of antigen on beads to modulate the avidity of the interaction between bead and secreted ant...

  3. Mental Labels and Tattoos

    Science.gov (United States)

    Hyatt, I. Ralph

    1977-01-01

    Discusses the ease with which mental labels become imprinted in our system, six basic axioms for maintaining negative mental tattoos, and psychological processes for eliminating mental tattoos and labels. (RK)

  4. Pesticide Product Label System

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Pesticide Product Label System (PPLS) provides a collection of pesticide product labels (Adobe PDF format) that have been approved by EPA under Section 3 of the...

  5. A new sensitive immunosorbent radioassay for the detection of circulating antibodies to polypeptide hormones and proteins

    International Nuclear Information System (INIS)

    A solid-phase immunosorbent radioassay for the detection of circulating antibodies to protein hormones is described. The assay is based on the binding of the homologous 125I-labelled antigen to the antibodies which are then bound to anti-IgG antibodies covalently coupled to Sepharose. It can easily be applied as a complement to any radioimmunoassay for the detection of circulating antibodies to the ligand measured. The assay system avoids falsely elevated values due to interference of high serum concentrations of the antigen. The assay was applied to measure antibodies to FSH, LH, TSH, GH, prolactin, insulin and thyroglobulin (Tg). Among patients with chronic thyroiditis Tg antibodies were found in 100% of the sera. In diffuse toxic goitre 73% of the patients had detectable Tg antibodies. Insulin antibodies were present in 82% of the sera from patients with insulin treated diabetes. No antibodies were found against the other protein hormones tested. (author)

  6. Limitations in localising and killing tumours using radiolabelled antibodies

    International Nuclear Information System (INIS)

    Radiolabelled antibodies against tumours are being studied intensely for their use in tumour detection and tumour destruction. Although a host of different tumour types can be localised, results at present are no better than other scanning techniques. In addition no tumour has been eradicated using labelled antibodies. Dramatic improvements will depend upon a fuller understanding of tumour cell biology and optimising all the parameters involved. (orig.)

  7. Characterization of Multienzyme-Antibody-Carbon Nanotube Bioconjugates for Immunosensors

    OpenAIRE

    Jensen, Gary C.; Yu, Xin; Gong, Joseph D.; Munge, Bernard; Bhirde, Ashwin; Kim, Sang N.; Papadimitrakopoulos, Fotios; Rusling, James F.

    2009-01-01

    Characterization studies of a multi-enzyme-antibody-carbon nanotube bioconjugate designed for the amplification of electrochemical immunosensing are described. Secondary antibodies for prostate specific antigen (PSA) were covalently linked to highly carboxylated multi-walled carbon nanotube (CNT) along with multiple horseradish peroxidase (HRP) enzyme labels. These bioconjugates provide ultra-sensitive amperometric detection of PSA on a single-wall carbon nanotube forest sandwich immunosensor...

  8. Current research status of radioimmunotherapy monoclonal antibody drug

    International Nuclear Information System (INIS)

    Radioimmunotherapy (RIT) was one of the most important progresses in the field of cancer therapy over the past 20 years. It has been successfully applied in the treatment of blood system tumors such as NHL. For the utilization of RIT in therapy of solid tumors, however, development of more effective monoclonal antibodies, labeling methods and so on are needed. The current status of radionuclides, monoclonal antibodies and drugs commonly used in the RIT were briefly reviewed. (authors)

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

    DEFF Research Database (Denmark)

    Han, Anpan; Dufva, Martin; Belleville, Erik;

    2003-01-01

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

  10. New Antibody Conjugates in Cancer Therapy

    Directory of Open Access Journals (Sweden)

    Serengulam V. Govindan

    2010-01-01

    Full Text Available Targeting of radiation, drugs, and protein toxins to cancers selectively with monoclonal antibodies (MAbs has been a topic of considerable interest and an area of continued development. Radioimmunotherapy (RAIT of lymphoma using directly labeled MAbs is of current interest after approval of two radiolabeled anti-CD20 MAbs, as illustrated with the near 100% overall response rate obtained in a recent clinical trial using an investigational radiolabeled anti-CD22 MAb, 90Y-epratuzumab. The advantage of pretargeted RAIT over directly labeled MAbs is continuing to be validated in preclinical models of lymphoma and solid tumors. Importantly, the advantages of combining RAIT with radiation sensitizers, with immunotherapy, or a drug conjugate targeting a different antigen are being studied clinically and preclinically. The area of drug-conjugated antibodies is progressing with encouraging data published for the trastuzumab-DM1 conjugate in a phase I clinical trial in HER2-positive breast cancer. The Dock-and-Lock platform technology has contributed to the design and the evaluation of complex antibody-cytokine and antibody-toxin conjugates. This review describes the advances made in these areas, with illustrations taken from advances made in the authors' institutions.

  11. On Online Labeling with Polynomially Many Labels

    DEFF Research Database (Denmark)

    Babka, Martin; Bulánek, Jan; Cunat, Vladimír; Koucky, Michal; Saks, Michael

    2012-01-01

    In the online labeling problem with parameters n and m we are presented with a sequence of nkeys from a totally ordered universe U and must assign each arriving key a label from the label set {1,2,…,m} so that the order of labels (strictly) respects the ordering on U. As new keys arrive it may be...... necessary to change the labels of some items; such changes may be done at any time at unit cost for each change. The goal is to minimize the total cost. An alternative formulation of this problem is the file maintenance problem, in which the items, instead of being labeled, are maintained in sorted order in...... are known that use O(n logn) relabelings. A matching lower bound was claimed in [7]. That proof involved two distinct steps: a lower bound for a problem they call prefix bucketing and a reduction from prefix bucketing to online labeling. The reduction seems to be incorrect, leaving a (seemingly...

  12. Antiphospholipid Antibody Syndrome

    Science.gov (United States)

    ... page from the NHLBI on Twitter. What Is Antiphospholipid Antibody Syndrome? Antiphospholipid (AN-te-fos-fo-LIP-id) antibody ... weeks or months. This condition is called catastrophic antiphospholipid syndrome (CAPS). People who have APS also are at ...

  13. The antibody mining toolbox

    OpenAIRE

    D'Angelo, Sara; Glanville, Jacob; Ferrara, Fortunato; Naranjo, Leslie; Gleasner, Cheryl D.; Shen, Xiaohong; Bradbury, Andrew RM; Kiss, Csaba

    2013-01-01

    In vitro selection has been an essential tool in the development of recombinant antibodies against various antigen targets. Deep sequencing has recently been gaining ground as an alternative and valuable method to analyze such antibody selections. The analysis provides a novel and extremely detailed view of selected antibody populations, and allows the identification of specific antibodies using only sequencing data, potentially eliminating the need for expensive and laborious low-throughput ...

  14. Dual-Quantum-Dots-Labeled Lateral Flow Strip Rapidly Quantifies Procalcitonin and C-reactive Protein

    OpenAIRE

    Qi, Xiaoping; Huang, YunYe; Lin, ZhongShi; Xu, Liang; Yu, Hao

    2016-01-01

    In the article, a dual-quantum-dots-labeled (dual-QDs-labeled) lateral flow strip (LFS) method was developed for the simultaneous and rapid quantitative detection of procalcitonin (PCT) and C-reactive protein (CRP) in the blood. Two QD-antibody conjugates with different fluorescence emission spectra were produced and sprayed on the LFS to capture PCT and CRP in the blood. Furthermore, a double antibody sandwich method for PCT and, meanwhile, a competitive inhibition method for CRP were employ...

  15. Heavy chain only antibodies

    DEFF Research Database (Denmark)

    Moghimi, Seyed Moein; Rahbarizadeh, Fatemeh; Ahmadvand, Davoud;

    2013-01-01

    Unlike conventional antibodies, heavy chain only antibodies derived from camel contain a single variable domain (VHH) and two constant domains (CH2 and CH3). Cloned and isolated VHHs possess unique properties that enable them to excel conventional therapeutic antibodies and their smaller antigen...

  16. Computer Programmes for Multiple Labelling Techniques Involving Two or More Radioiodines

    International Nuclear Information System (INIS)

    The use of radioiodine to label proteins has proven to be a very important tool in both immunochemistry and protein chemistry. Its use and importance has been greatly enhanced by the development of multiple label techniques in which two or more proteins can be iodinated individually with different radioiodines and then mixed and run through various experimental conditions with the knowledge that the conditions to which the proteins are exposed are thus identical. This has been particularly useful in determining whether antibodies prepared against a tumor actually localize specifically in the tumor. Tumors have the property of picking up injected foreign proteins non-specifically and not in a uniform manner. Moreover tumors, even experimental tumors of the same type, vary from individual to individual so that it is not valid to determine whether or not an antibody preparation localizes in the tumor by injecting one individual with an antitumor antibody preparation and another with the control preparation. Excellent control has been obtained however by the Paired Label Technique in which a single individual is injected simultaneously with 131l labelled antibody and 125I labelled control globulin. Then the fixation of antibody can be compared with the fixation of control protein in any particular piece of the tumor as well as in the tumor as a whole. By the use of three iodines as in the Triad Label Technique, data of much greater significance can be obtained because antitumor antibodies, antinormal tissue antibodies and control globulin can all be assayed simultaneously in the same tumor. Up till now limited use has been made of the Triad Label Technique because of the short lives of the third isotope available and because of the amount of computation required. We have now devised programmes in Fortran IV for use on the IBM 7040, 7044 etc. computers which make the Triad Label Technique a practical method, not only for tumor studies but for protein structure studies

  17. 99mTc: Labeling Chemistry and Labeled Compounds

    Science.gov (United States)

    Alberto, R.; Abram, U.

    This chapter reviews the radiopharmaceutical chemistry of technetium related to the synthesis of perfusion agents and to the labeling of receptor-binding biomolecules. To understand the limitations of technetium chemistry imposed by future application of the complexes in nuclear medicine, an introductory section analyzes the compulsory requirements to be considered when facing the incentive of introducing a novel radiopharmaceutical into the market. Requirements from chemistry, routine application, and market are discussed. In a subsequent section, commercially available 99mTc-based radiopharmaceuticals are treated. It covers the complexes in use for imaging the most important target organs such as heart, brain, or kidney. The commercially available radiopharmaceuticals fulfill the requirements outlined earlier and are discussed with this background. In a following section, the properties and perspectives of the different generations of radiopharmaceuticals are described in a general way, covering characteristics for perfusion agents and for receptor-specific molecules. Technetium chemistry for the synthesis of perfusion agents and the different labeling approaches for target-specific biomolecules are summarized. The review comprises a general introduction to the common approaches currently in use, employing the N x S4-x , [3+1] and 2-hydrazino-nicotinicacid (HYNIC) method as well as more recent strategies such as the carbonyl and the TcN approach. Direct labeling without the need of a bifunctional chelator is briefly reviewed as well. More particularly, recent developments in the labeling of concrete targeting molecules, the second generation of radiopharmaceuticals, is then discussed and prominent examples with antibodies/peptides, neuroreceptor targeting small molecules, myocardial imaging agents, vitamins, thymidine, and complexes relevant to multidrug resistance are given. In addition, a new approach toward peptide drug development is described. The section

  18. Monoclonal antibodies and cancer

    International Nuclear Information System (INIS)

    The usefulness of radiolabeled monoclonal antibodies for imaging and treatment of human (ovarian) cancer was investigated. A review of tumor imaging with monoclonal antibodies is presented. Special attention is given to factors that influence the localization of the antibodies in tumors, isotope choice and methods of radiolabeling of the monoclonal antibodies. Two monoclonal antibodies, OC125 and OV-TL3, with high specificity for human epithelial ovarian cancer are characterized. A simple radio-iodination technique was developed for clinical application of the monoclonal antibodies. The behavior of monoclonal antibodies in human tumor xenograft systems and in man are described. Imaging of tumors is complicated because of high background levels of radioactivity in other sites than the tumor, especially in the bloodpool. A technique was developed to improve imaging of human tumor xenographs in nude mice, using subtraction of a specific and a non-specific antibody, radiolabeled with 111In, 67Ga and 131I. To investigate the capability of the two monoclonal antibodies, to specifically localize in human ovarian carcinomas, distribution studies in mice bearing human ovarian carcinoma xenografts were performed. One of the antibodies, OC125, was used for distribution studies in ovarian cancer patients. OC125 was used because of availability and approval to use this antibody in patients. The same antibody was used to investigate the usefulness of radioimmunoimaging in ovarian cancer patients. The interaction of injected radiolabeled antibody OC125 with circulating antigen and an assay to measure the antibody response in ovarian cancer patients after injection of the antibody is described. 265 refs.; 30 figs.; 19 tabs

  19. A monoclonal antibody toolkit for C. elegans.

    Directory of Open Access Journals (Sweden)

    Gayla Hadwiger

    Full Text Available BACKGROUND: Antibodies are critical tools in many avenues of biological research. Though antibodies can be produced in the research laboratory setting, most research labs working with vertebrates avail themselves of the wide array of commercially available reagents. By contrast, few such reagents are available for work with model organisms. METHODOLOGY/PRINCIPAL FINDINGS: We report the production of monoclonal antibodies directed against a wide range of proteins that label specific subcellular and cellular components, and macromolecular complexes. Antibodies were made to synaptobrevin (SNB-1, a component of synaptic vesicles; to Rim (UNC-10, a protein localized to synaptic active zones; to transforming acidic coiled-coil protein (TAC-1, a component of centrosomes; to CENP-C (HCP-4, which in worms labels the entire length of their holocentric chromosomes; to ORC2 (ORC-2, a subunit of the DNA origin replication complex; to the nucleolar phosphoprotein NOPP140 (DAO-5; to the nuclear envelope protein lamin (LMN-1; to EHD1 (RME-1 a marker for recycling endosomes; to caveolin (CAV-1, a marker for caveolae; to the cytochrome P450 (CYP-33E1, a resident of the endoplasmic reticulum; to beta-1,3-glucuronyltransferase (SQV-8 that labels the Golgi; to a chaperonin (HSP-60 targeted to mitochondria; to LAMP (LMP-1, a resident protein of lysosomes; to the alpha subunit of the 20S subcomplex (PAS-7 of the 26S proteasome; to dynamin (DYN-1 and to the alpha-subunit of the adaptor complex 2 (APA-2 as markers for sites of clathrin-mediated endocytosis; to the MAGUK, protein disks large (DLG-1 and cadherin (HMR-1, both of which label adherens junctions; to a cytoskeletal linker of the ezrin-radixin-moesin family (ERM-1, which localized to apical membranes; to an ERBIN family protein (LET-413 which localizes to the basolateral membrane of epithelial cells and to an adhesion molecule (SAX-7 which localizes to the plasma membrane at cell-cell contacts. In addition to

  20. Selective Serial Multi-Antibody Biosensing with TOPAS Microstructured Polymer Optical Fibers

    DEFF Research Database (Denmark)

    Emiliyanov, Grigoriy Andreev; Høiby, Poul E.; Pedersen, Lars H.; Bang, Ole

    2013-01-01

    We have developed a fluorescence-based fiber-optical biosensor, which can selectively detect different antibodies in serial at preselected positions inside a single piece of fiber. The fiber is a microstructured polymer optical fiber fabricated from TOPAS cyclic olefin copolymer, which allows for...... UV activation of localized sensor layers inside the holes of the fiber. Serial fluorescence-based selective sensing of Cy3-labelled α-streptavidin and Cy5-labelled α-CRP antibodies is demonstrated....

  1. Site-specific antibodies to human erythropoietin directed toward the NH2-terminal region.

    OpenAIRE

    Sue, J M; Sytkowski, A. J.

    1983-01-01

    Site-specific antibodies to human erythropoietin have been raised in rabbits immunized with a synthetic polypeptide composed of the putative 26 NH2-terminal amino acids of the hormone. The immunogenic peptide was coupled to bovine serum albumin. Antibodies specific for peptide were detected by enzyme-linked immunosorbent assay. They immunoprecipitated both highly purified 125I-labeled erythropoietin and biologically active erythropoietin. The immunoprecipitation of 125I-labeled erythropoietin...

  2. Measurement of anti-enzyme antibodies using an active-site directed radiolabel

    International Nuclear Information System (INIS)

    A new technique is described for measuring antibodies to an enzyme which is not available in pure form. The secretions of the rat parasitic nematode, Nippostrongylus brasiliensis, were treated with tritiated diisopropylfluorophosphate. Only one component, an acetylcholinesterase, was radiolabelled. Antibodies to this enzyme in rat antisera were estimated by the Farr technique using the labelled enzyme as antigen. The acetylcholinesterase secreted by Necator Americanus, the human hookworm, was similarly specifically labelled

  3. The effects of variations in the specificities of the antibody components on a two-site immunoradiometric assay for ferritin

    International Nuclear Information System (INIS)

    Variations in the sub-unit antigenic structure of ferritins derived from various human tissues are reflected in the differing specificities of antisera raised against these ferritin preparations. In this study it was shown that antibody specificity played an important role in determining the sensitivity and overall binding of labelled antibody in a two-site immunoradiometric assay for ferritin. Homologous assay systems, in which solid phase and radio-labelled antibodies were of similar specificities, were generally less sensitive and showed lower binding than heterologous assay systems, in which solid phase and labelled antibodies were of different specificities. The source of the ferritin which was used as assay standard also played an important part in determining the sensitivity and overall binding in homologous antibody systems, spleen ferritin standards yielding assays superior to those obtained with placenta or liver ferritin standards. However, these differences between standards were not seen in a heterologous system employing solid-phase antibodies directed against liver ferritin and labelled antibodies directed against placenta ferritin. The nature of the ferritin used to prepare immunoadsorbant for the purification of antibodies before radioiodination also affected the assay characteristics; antibodies prepared on spleen ferritin immunoadsorbant being more reactive than antibodies prepared on placenta ferritin immunoadsorbant, which in turn were more reactive than antibodies prepared on liver ferritin immunoadsorbant. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1988-01-01

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

  5. Selective detection of antibodies in microstructured polymer optical fibers

    DEFF Research Database (Denmark)

    Jensen, Jesper Bo Damm; Hoiby, P.E.; Emiliyanov, Grigoriy Andreev;

    2005-01-01

    We demonstrate selective detection of fluorophore labeled antibodies from minute samples probed by a sensor layer of complementary biomolecules immobilized inside the air holes of microstructured Polymer Optical Fiber (mPOF). The fiber core is defined by a ring of 6 air holes and a simple procedure...... was applied to selectively capture either α-streptavidin or α-CRP antibodies inside these air holes. A sensitive and easy-to-use fluorescence method was used for the optical detection. Our results show that mPOF based biosensors can provide reliable and selective antibody detection in ultra small...

  6. Dosimetry of radiolabeled monoclonal antibodies used for therapy

    International Nuclear Information System (INIS)

    The present state of radiotherapy using labeled antibodies is reviewed. From the point of view of dosimetry, antibody therapy does not seem to have reached a stable and practicable enough state to provide an input to any but rather tentative dosimetry models. These, therefore, should not be taken too far until the problems of antibody targeting have been more fully developed. Some of the instrumental techniques for acquiring dosimetric data under clinical conditions are discussed as are some of the techniques of therapy in use today. 8 references, 3 figures

  7. IgE antibody responses in schistosomiasis measured by a radioallergosorbent test

    International Nuclear Information System (INIS)

    Helminth infections are associated with the production of unusually high concentrations of circulating IgE antibody. Assays for IgE antibodies should provide useful approaches for the study of protective immunity and may also be of use in serodiagnosis of diseases induced by helminths. The radioallergosorbent test is carried out by attaching the antigen or allergen to an insoluble supportive material, allowing the IgE antibodies in the test serum to react with excess bound antigen, and then estimating the IgE antibody bound by its reaction with 125I-labelled goat anti-human IgE antibody

  8. No-labeled immunoassay by using surface plasmon resonance biosensor

    International Nuclear Information System (INIS)

    Surface plasmon resonance biosensor was used to develop fast no-labeled immunoassays for sulfamethazine and sulfadiazine. The immobilization conditions of the antigen were studied and the working concentration of antibody and the condition of regeneration were optimized. Standard curves were set up and the stability of the chip was studied. (authors)

  9. Chromium labeling of erythrocytes and their application in clearance and sequestration studies during malaria

    International Nuclear Information System (INIS)

    The erythrocyte labeling, clearance and sequestration procedures are outlined for the mouse model system. Significant hematologic and pathologic changes occur during malaria infection, among them anemia, hypocomplementemia, hepatomegaly and splenomegaly. The 51Cr-label studies have been performed to determine the effects of Plasmodium bergheii malaria infection upon the course of clearance and sequestration of antibody-sensitized erythrocytes

  10. Addressing challenges in preparation of 211At-labeled biomolecules for use in targeted alpha therapy

    International Nuclear Information System (INIS)

    There are significant challenges in the development of 211At-labeled biomolecules for application to targeted alpha therapy. Challenges that we have addressed include development of: (1) labeling methods to obtain high in vivo 211At-label stability, (2) approaches to consistently obtain high recovery yields of Na[211At]At from irradiated bismuth targets, (3) methods to optimize biomolecule labeling yields, (4) reagents for use of 211At in pretargeting approach to cancer therapy, and (5) 211At-labeled antibodies in conditioning for hematopoietic cell transplantation. (author)

  11. Antibody-radioisotope conjugates for tumor localization and treatment

    International Nuclear Information System (INIS)

    In principle, anti-tumor antibodies can be used to carry radioactivity to tumors for in-vivo diagnosis and treatment of cancer. First, for diagnostic purposes, an antibody that targets a specific antigen (for example, the p97 antigen of human melanoma tumor), is labeled with a tracer amount of radioactivity. When this antibody-radioisotope conjugate is injected into the blood stream, the antibody carries the radioactivity throughout the body and in time, percolates through all the tissues of the body. Because the tumor has specific antigens to which the antibody can bind, the antibody conjugate progressively accumulates in the tumor. Using conventional nuclear medicine imaging equipment, the body of the patient is scanned for radioactivity content, and a map of the distribution of the radioactivity is displayed on photographic film. The tumor shows up as a dense area of radio-activity. These same antibody-radioisotope conjugates may be used for therapy of tumors, except that in this case large amounts of radioactivity are loaded on the antibody. After localization of the conjugate there is sufficient radiation deposited in the tumor of radiotherapy. The success of this approach in the clinic is determined in large measure by the concentration gradient that can be achieved between tissue antibody conjugate in tumor versus normal tissue

  12. Method and cell lines for the production of monoclonal antibodies to human glycophorin A

    Science.gov (United States)

    Bigbee, W.L.; Fong, S.S.N.; Jensen, R.H.; Vanderlaan, M.

    Cloned mouse hybridoma cell lines have been established which continuously produce antibodies that differentiate between the M and N forms of human glycophorin A. These antibodies have potential application as human blood group reagents, as markers for terminally differentiated erythroid cells and as immunofluorescent labels of somatically variant human erythrocytes.

  13. Quantification of antibody production of individual hybridoma cells by Surface Plasmon Resonance imaging.

    NARCIS (Netherlands)

    Stojanovic, I.; Velden, van der T.J.G.; Mulder, H.W.; Schasfoort, R.B.M.; Terstappen, L.W.M.M.

    2015-01-01

    Surface plasmon resonance imaging (SPRi) is most frequently used for the label-free measurement of biomolecular interactions. Here we explore the potential of SPRi to measure antibody production of individual hybridoma cells. As a model system, cells from a hybridoma, producing monoclonal antibodies

  14. Monoclonal Antibody Analysis of Keratin Expression in the Central Nervous System

    Science.gov (United States)

    Franko, Maryellen C.; Gibbs, Clarence J.; Rhoades, Dorothy A.; Carleton Gajdusek, D.

    1987-05-01

    A monoclonal antibody directed against a 65-kDa brain protein demonstrates an epitope found in keratin from human epidermis. By indirect immunofluorescence, the antibody decorates intracytoplasmic filaments in a subclass of astrocytes and Purkinje cells of adult hamster brain. Double-label immunofluorescence study using antibody to glial fibrillary acidic protein and this antibody reveals the 65-kDa protein to be closely associated with glial filaments in astrocytes of fetal mouse brain cultures. Immunoblot analysis of purified human epidermal keratin and hamster brain homogenate confirms the reactivity of this antibody to epidermal keratin polypeptides. All the major epidermal keratins were recognized by this antibody. It did not bind to the remaining major intermediate filament proteins. These findings suggest that monoclonal antibody 34C9 recognizes a cytoskeletal structure connected with intermediate filaments. In addition, the monoclonal antibody demonstrates that epidermal keratins share an epitope not only among themselves but also with a ``neural keratin.''

  15. Radioiodine labelling of insulin using dimethylsulfoxide as a labelling-aid

    International Nuclear Information System (INIS)

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

  16. Deuterium labeled cannabinoids

    International Nuclear Information System (INIS)

    Complex reactions involving ring opening, ring closure and rearrangements hamper complete understanding of the fragmentation processes in the mass spectrometric fragmentation patterns of cannabinoids. Specifically labelled compounds are very powerful tools for obtaining more insight into fragmentation mechanisms and ion structures and therefore the synthesis of specifically deuterated cannabinoids was undertaken. For this, it was necessary to investigate the preparation of cannabinoids, appropriately functionalized for specific introduction of deuterium atom labels. The results of mass spectrometry with these labelled cannabinoids are described. (Auth.)

  17. Labelling Fashion Markets

    OpenAIRE

    Aspers, P.

    2008-01-01

    The present article discusses how an ethical and environmental labelling system can be implemented in fashion garment markets. Consumers act in markets that provide them with more information than their limited cognitive capacity allows them to handle. Ethical and environmental labelling in markets characterized by change, such as the fashion garment market, makes decision-making even more complicated. The ethical and environmental labelling system proposed here is designed to alleviate firms...

  18. Blood cell labelling

    International Nuclear Information System (INIS)

    The labelling of blood cells in vitro for subsequent in vivo studies was one of the earliest applications of radioactive tracers in clinical medicine and laid the foundations for many important contributions to the advancement of knowledge of human blood cell pathophysiology. The characteristics required for satisfactory clinical studies, the mechanisms of cell labelling, the problems of radiation or chemical damage to the labelled cells and some examples of modern clinical applications are described and discussed. (Author)

  19. Affitins as alternative to antibodies

    International Nuclear Information System (INIS)

    Full text of publication follows. We have developed the use of Sac7d archaeal polypeptide and its homologues as a non-antibody scaffold from which artificial affinity proteins (Affitins) can be derived with a number of favorable properties. Affitins show affinity (sub-nanomolar) and specificity that compare well with those of antibodies [Ref.1]. They are thermally (up to 90 C. degrees) and chemically stable (pH 0-12+, denaturants), well expressed in E. coli (up to 200 mg/L), lack disulfide bridge and have a size compatible with chemical synthesis (7 kDa). We have demonstrated their use as reagents for intra-cellular inhibition [Ref.1], affinity purification [Ref.2], immuno-localization [Ref.3], protein chip array [Ref.4] and biosensors [Ref.5]. We have also shown that Affitins are plastic enough to tolerate several mutagenesis schemes while their fold and their favorable properties are conserved [Ref.6]. Compared to Affitins, monoclonal antibodies are 20 times larger, less stable and more complex molecules. Furthermore, the remarkable stability properties of Affitins make them suited for demanding labeling protocols that are usually used for peptides. All together, these results show that Affitins should be well suited for biomedical applications where fine tuning of the affinity reagent properties is needed. References: [Ref.1] Mouratou, B. et al., (2007), Proc Natl Acad Sci U S A 104, 17983-17988; [Ref.2] Krehenbrink, M. et al. (2008), J Mol Biol 383, 1058-1068; [Ref.3] Buddelmeijer, N. et al. (2009), J Bacteriol 191, 161-168; [Ref.4] Cinier, M. et al. (2009), Bioconjug. Chem. 20, 2270-2277; [Ref.5] Miranda, F. F. et al. (2011), Biosens. Bioelectron. 26, 4184-4190; [Ref.6] Behar G.et al. (2013), Protein Eng Des Sel. 26(4):267-75. (authors)

  20. Purification of Mitochondrial Proteins HSP60 and ATP Synthase from Ascidian Eggs: Implications for Antibody Specificity

    OpenAIRE

    Chenevert, Janet; Pruliere, Gerard; Ishii, Hirokazu; Sardet, Christian; Nishikata, Takahito

    2013-01-01

    Use of antibodies is a cornerstone of biological studies and it is important to identify the recognized protein with certainty. Generally an antibody is considered specific if it labels a single band of the expected size in the tissue of interest, or has a strong affinity for the antigen produced in a heterologous system. The identity of the antibody target protein is rarely confirmed by purification and sequencing, however in many cases this may be necessary. In this study we sought to chara...

  1. The production of recombinant single chain antibody fragments for the detection of illicit drug residues

    OpenAIRE

    Brennan, Joanne

    2005-01-01

    Recombinant antibodies represent a more sensitive and specific detection tool for immunoanalysis. The research carried out for this thesis describes the production of genetically-derived single chain antibody fragments to detect illicit drugs. A variety of novel recombinant antibody fragments against morphine-3-glucuronide, a metabolite of heroin has been produced. A monomeric, dimeric and enzyme-labelled scFv were characterised with respect to their binding abilities and cross reactiviti...

  2. Effect of Fluorescently Labeling Protein Probes on Kinetics of Protein-Ligand Reactions

    OpenAIRE

    Sun, Y.S.; Landry, J. P.; Fei, Y.Y.; Zhu, X.D.; Luo, J. T.; Wang, X.B.; Lam, K. S.

    2008-01-01

    We studied the effect of fluorescently labeling proteins on protein-ligand reactions. Un-labeled ligands (streptavidin-binding peptides and rabbit immunoglobulin G (IgG) as antigen targets) are immobilized on epoxy-functionalized glass slides. Unlabeled and Cy3-labeled protein probes from the same batch (streptavidin and goat antibodies) subsequently react with the surface-immobilized targets. By monitoring in situ the surface mass density change using an oblique-incidence reflectivity differ...

  3. On labelled compounds nomenclature

    International Nuclear Information System (INIS)

    Different approaches of major labelled compounds producers to their nomenclature in technical and commercial documentation are discussed. Some draft options of a standard technical guide document for labelled compounds nomenclature rules are suggested. Such a document after due discussion by the experts will serve to unification of the labelled compounds nomenclature within the frame of the CMEA member-countries co-operation in this field. The suggested options are based on the general recommendations by the International Union of Pure and Applied Chemistry and incorporate some more accurate definitions originating from the labelled compounds production and application experience

  4. Development of Re-188 radiolabelling procedures of peptides and monoclonal antibodies

    International Nuclear Information System (INIS)

    The goal of this work was to study and select the parameters to label biomolecules directly with 188Re. The concrete objectives pursued were: (i) Labelling h-IgG with 188Re; (ii) Radiolabelling Lanreotide and anti-CEA monoclonal antibody with 188Re; investigation of chromatography based quality control techniques; (iii) Biodistribution studies in tumour bearing rats

  5. Development of labelled biomolecules for targeted radiotherapy. Mexico

    International Nuclear Information System (INIS)

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

  6. Engineering antibody therapeutics.

    Science.gov (United States)

    Chiu, Mark L; Gilliland, Gary L

    2016-06-01

    The successful introduction of antibody-based protein therapeutics into the arsenal of treatments for patients has within a few decades fostered intense innovation in the production and engineering of antibodies. Reviewed here are the methods currently used to produce antibodies along with how our knowledge of the structural and functional characterization of immunoglobulins has resulted in the engineering of antibodies to produce protein therapeutics with unique properties, both biological and biophysical, that are leading to novel therapeutic approaches. Antibody engineering includes the introduction of the antibody combining site (variable regions) into a host of architectures including bi and multi-specific formats that further impact the therapeutic properties leading to further advantages and successes in patient treatment. PMID:27525816

  7. Differentiation between monoclonal antibody - defined antigens on a human osteogenic sarcoma cell line (791-T) and Tumor-localizing properties of the anti-791T/36 antibody

    International Nuclear Information System (INIS)

    Two monoclonal antibodies (anti-791T/36 and anti-791T/48) prepared against an osteogenic sarcoma cell line (791T) following xenogeneic immunization, reacted against the immunizing tumor, but not against normal cells from the tumor-donor, using an indirect 125I-protein A binding assay. Both antibodies cross-reacted with a small number of other osteogenic sarcomas and a few unrelated cell lines from an extensive panel, but the specificity of these cross-reactions was different. Both antibodies were labelled with 125I to detect direct binding to target cells, and the specificity of their reactivity was essentially identical to that observed in the indirect assay. Direct binding of each labelled antibody was inhibited by pretreating target cells with its unlabelled counterpart, but the two antibodies could not inhibit each other. The binding of anti-791T/36 was also not inhibited by pretreating the target cells with sera from the 791-T-tumor donor, which were shown to contain antibody reacting with the autochthonous tumor. It is concluded that 791T has two distinct tumor-associated antigens recognized by the monoclonal antibodies, and furthermore that at least one of these antigens is independent of those recognized by the patient from which the tumor cell line was derived. The efficacy of anti-791T/36 antibody labelled with radioactive iodine was demonstrated for localizing tumor deposits growing in immunodeprived mice. (author)

  8. Estimation of antibodies to human cytomegalovirus by immunofluorescence and radioimmunoassay

    International Nuclear Information System (INIS)

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

  9. Preclinical evaluation of (111)In-DTPA-INCA-X anti-Ku70/Ku80 monoclonal antibody in prostate cancer.

    OpenAIRE

    Evans, Susan; Vilhelmsson Timmermand, Oskar; Welinder, Charlotte; Borrebaeck, Carl AK; Strand, Sven-Erik; Tran, Thuy; Jansson, Bo; Bjartell, Anders

    2014-01-01

    The aim of this investigation was to assess the Ku70/Ku80 complex as a potential target for antibody imaging of prostate cancer. We evaluated the in vivo and ex vivo tumor targeting and biodistribution of the (111)In-labeled human internalizing antibody, INCA-X ((111)In-DTPA-INCA-X antibody), in NMRI-nude mice bearing human PC-3, PC-3M-Lu2 or DU145 xenografts. DTPA-conjugated, non-labeled antibody was pre-administered at different time-points followed by a single intravenous injection of (111...

  10. Detection of antibodies to single-stranded DNA in naturally acquired and experimentally induced viral hepatitis

    International Nuclear Information System (INIS)

    A sensitive ''Farr'' assay, utilizing 125I-labelled DNA was developed for detecting antibody to single-stranded DNA (anti-ssDNA). The test was shown to be specific and as sensitive as assays using 14C-labelled DNA, for the detection of antibody in patients with connective tissue diseases. Groups of sera from patients with naturally acquired viral hepatitis and experimentally infected chimpanzees were tested for anti-ssDNA by the 125I assay and by counterimmunoelectrophoresis (CIEP). No consistent pattern was observed with either technique, indicating the elevated levels of this antibody are not as reliable markers of parenchymal liver damage as had been previously suggested

  11. Stable isotopes labelled compounds

    International Nuclear Information System (INIS)

    The catalogue on stable isotopes labelled compounds offers deuterium, nitrogen-15, and multiply labelled compounds. It includes: (1) conditions of sale and delivery, (2) the application of stable isotopes, (3) technical information, (4) product specifications, and (5) the complete delivery programme

  12. Labeling and Delinquency.

    Science.gov (United States)

    Adams, Mike S.; Robertson, Craig T.; Gray-Ray, Phyllis; Ray, Melvin C.

    2003-01-01

    Index comprised of six contrasting descriptive adjectives was used to measure incarcerated youths' perceived negative labeling from the perspective of parents, teachers, and peers. Results provided partial support for hypothesis that juveniles who choose a greater number of negative labels will report more frequent delinquent involvement. Labeling…

  13. Label Fusion Strategy Selection

    Directory of Open Access Journals (Sweden)

    Nicolas Robitaille

    2012-01-01

    Full Text Available Label fusion is used in medical image segmentation to combine several different labels of the same entity into a single discrete label, potentially more accurate, with respect to the exact, sought segmentation, than the best input element. Using simulated data, we compared three existing label fusion techniques—STAPLE, Voting, and Shape-Based Averaging (SBA—and observed that none could be considered superior depending on the dissimilarity between the input elements. We thus developed an empirical, hybrid technique called SVS, which selects the most appropriate technique to apply based on this dissimilarity. We evaluated the label fusion strategies on two- and three-dimensional simulated data and showed that SVS is superior to any of the three existing methods examined. On real data, we used SVS to perform fusions of 10 segmentations of the hippocampus and amygdala in 78 subjects from the ICBM dataset. SVS selected SBA in almost all cases, which was the most appropriate method overall.

  14. OR Specimen Labeling.

    Science.gov (United States)

    Zervakis Brent, Mary Ann

    2016-02-01

    Mislabeled surgical specimens jeopardize patient safety and quality care. The purpose of this project was to determine whether labeling surgical specimens with two patient identifiers would result in an 80% reduction in specimen labeling errors within six months and a 100% reduction in errors within 12 months. Our failure mode effects analysis found that the lack of two patient identifiers per label was the most unsafe step in our specimen handling process. We piloted and implemented a new process in the OR using the Plan-Do-Check-Act conceptual framework. The audit process included collecting data and making direct observations to determine the sustainability of the process change; however, the leadership team halted the direct observation audit after four months. The total number of surgical specimen labeling errors was reduced by only 60% within six months and 62% within 12 months; therefore, the goal of the project was not met. However, OR specimen labeling errors were reduced. PMID:26849982

  15. Radioiodine and its labelled compounds

    International Nuclear Information System (INIS)

    Chemical characteristics and their nuclear characteristics, types of labelled molecules,labelling procedures, direct labelling with various oxidizing agents, indirect labelling with various conjugates attached to protein molecules, purification and quality control. Iodination damage.Safe handling of labelling procedures with iodine radioisotopes.Bibliography

  16. Study on the Radioiodination of Sheep Anti-myeloma Polyclonal Antibodies for the Determination of in-vitro Cytotoxic Effect on Myeloma Cells

    International Nuclear Information System (INIS)

    The present work aims to study the effect of radiolabeled anti-myeloma polyclonal antibodies on the growth and viability of myeloma cells in-vitro. Two Sheep were immunized by myeloma cells (SP2/OR) as antigen. Productions of Sheep anti-myeloma polyclonal antibodies followed by radioiodination using different oxidizing agents were carried out. Labeled and unlabeled antibodies were incubated with myeloma cells. Growth and viability of myeloma cells were investigated before and after addition of antibodies. The results show significant reduction in growth and viability of myeloma cells by using labeled antibodies. This technique of treatment can be used in radio-immunotherapy of myeloma cell

  17. The effects of variations in the specificities of the antibody components on a two-site immunoradiometric assay for ferritin

    International Nuclear Information System (INIS)

    Variations in the sub-unit antigenic structure of ferritins derived from various human tissues are reflected in the differing specificities of antisera raised against these ferritin preparations. In this study it was shown that antibody specificity played an important role in determining the sensitivity and overall binding of labelled antibody in a two-site immunoradiometric assay for ferritin. Homologous assay systems, in which solid phase and radiolabelled antibodies were of similar specificities, were generally less sensitive and showed lower binding than heterologous assay systems, in which solid phase and labelled antibodies were of different specificities. The source of the ferritin which was used as assay standard also played an important part in determining the sensitivity and overall binding in homologous antibody systems, spleen ferritin standards yielding assays superior to those obtained with placenta or liver ferritin standards. However, these differences between standards were not seen in a heterologous system employing solid phase antibodies directed against liver ferritin and labelled antibodies directed against placenta ferritin. The nature of the ferritin used to prepare immunoadsorbant for the purification of antibodies prior to radioiodination also affected the assay characteristics; antibodies prepared on spleen ferritin immunoadsorbant being more reactive than antibodies prepared on placenta ferritin immunoadsorbant, which in turn were more reactive then antibodies prepared on liver ferritin immunoadsorbant. (orig.)

  18. Microfluidic Radiometal Labeling Systems for Biomolecules

    Energy Technology Data Exchange (ETDEWEB)

    Reichert, D E; Kenis, P J. A.

    2011-12-29

    In a typical labeling procedure with radiometals, such as Cu-64 and Ga-68; a very large (~ 100-fold) excess of the non-radioactive reactant (precursor) is used to promote rapid and efficient incorporation of the radioisotope into the PET imaging agent. In order to achieve high specific activities, careful control of reaction conditions and extensive chromatographic purifications are required in order to separate the labeled compounds from the cold precursors. Here we propose a microfluidic approach to overcome these problems, and achieve high specific activities in a more convenient, semi-automated fashion and faster time frame. Microfluidic reactors, consisting of a network of micron-sized channels (typical dimensions in the range 10 - 300¼m), filters, separation columns, electrodes and reaction loops/chambers etched onto a solid substrate, are now emerging as an extremely useful technology for the intensification and miniaturization of chemical processes. The ability to manipulate, process and analyze reagent concentrations and reaction interfaces in both space and time within the channel network of a microreactor provides the fine level of reaction control that is desirable in PET radiochemistry practice. These factors can bring radiometal labeling, specifically the preparation of radio-labeled biomolecules such as antibodies, much closer to their theoretical maximum specific activities.

  19. Affinity purification of antibodies

    Science.gov (United States)

    Antibodies are provided in a variety of formats that includes antiserum, hybridoma culture supernatant or ascites. They can all be used successfully in crude form for the detection of target antigens by immunoassay. However, it is advantageous to use purified antibody in defined quantity to facil...

  20. Therapeutic Recombinant Monoclonal Antibodies

    Science.gov (United States)

    Bakhtiar, Ray

    2012-01-01

    During the last two decades, the rapid growth of biotechnology-derived techniques has led to a myriad of therapeutic recombinant monoclonal antibodies with significant clinical benefits. Recombinant monoclonal antibodies can be obtained from a number of natural sources such as animal cell cultures using recombinant DNA engineering. In contrast to…

  1. Production Of Human Antibodies

    Science.gov (United States)

    Sammons, David W.; Neil, Garry A.

    1993-01-01

    Process for making human monoclonal antibodies based on combination of techniques. Antibodies made active against specific antigen. Process involves in vivo immunization of human B lymphocyte cells in mice. B cells of interest enriched in vitro before fusion. Method potentially applicable to any antigen. Does not rely on use of Epstein-Barr virus at any step. Human lymphocytes taken from any source.

  2. RBC Antibody Screen

    Science.gov (United States)

    ... the baby is Rh-positive and the mother's antibody status is negative for anti-D, the mother is given additional RhIG. This test also may be used to help diagnose autoimmune-related hemolytic anemia ... when a person produces antibodies against his or her own RBC antigens. This ...

  3. Antibody affinity maturation

    DEFF Research Database (Denmark)

    Skjødt, Mette Louise

    Yeast surface display is an effective tool for antibody affinity maturation because yeast can be used as an all-in-one workhorse to assemble, display and screen diversified antibody libraries. By employing the natural ability of yeast Saccharomyces cerevisiae to efficiently recombine multiple DNA...

  4. In vivo detection of prostatic carcinoma with antibodies against prostatic acid phosphatase

    International Nuclear Information System (INIS)

    Serum prostatic acid phosphates (PAP) immunoassay is used to evaluate patients with prostatic carcinoma; however, as with other tumor markers, the enzyme levels do not necessarily reflect the presence or extent of tumor. The authors investigated the use of radiolabeled PAP antibodies for the in vivo detection of prostatic carcinoma by external scintillation imaging. Nine patients with prostatic carcinoma were entered into the study. Each received from 2.0 to 2.5 mCi of I-131 labeled antibody to PAP, administered i.v. The immunogen (PAP) was purified from normal human seminal fluid. Antiserum was prepared in rabbits by injecting the purified PAP. The antibodies were labeled with I-131 by chloramine-T method (10 to 20 Ci/g of IgG). Total body images were obtained at 24 and 48 hrs following administration of the labeled antibody. Nontarget I-131 activity was diminished by computer processing. Tumor sites detected by I-131 antibodies were correlated with other diagnostic procedures. In 7 of 9 patients primary and metastatic sites of cancer were detected by antibody imaging, however, no bone lesions were detected (6 cases). In 3 patients with concomitant pulmonary tumors, one was identified as of prostate origin. The serum PAP was normal in 4 patients; however, the primary tumor was identified in 3 of these. These findings suggest that the localization of prostatic carcinoma by means of in-vivo imaging of labeled antibodies to PAP is feasible and offers diagnostic opportunities based upon the functional characteristics

  5. In vivo modulators of antibody kinetics

    International Nuclear Information System (INIS)

    The aim of the present study was to summarize the effect of in vivo modulation of antibody kinetics and to present new data on the in vivo effect of the cell membrane active detergent Tween 80 and the cytokine interleukin-2 (IL-2) on the accumulation and clearance of a radioactive antibody. Mice bearing Lewis lung carcinoma xenografts and rats bearing DMBA-induced mammary carcinomas were studied after injecting I-125 labeled IgG1 monoclonal antibody (3c4c7g6) raised against a tyrosine kinase receptor protein Tie. Expression of Tie is known to be abundant in vascular endothelia and possibly related to malignant angiogenesis. Tween 80 was administered intratumorally (0.04% of tumor volume), whereas IL-2 was administered intraperitoneally. In the Lewis lung tumor model, the absolute tumor uptake varied between 2 and 5% ID/g, and maximum uptake was achieved after 24 h with Tween, and after 48 h without Tween. Tween manipulation did not increase the uptake in any normal organ, but it enhanced antibody clearance form the blood. In the DMBA rat model, IL-2 had no effect on blood clearance, but enhanced the uptake of Tie antibody into the tumor from 2.5-0.9 to 4.5-0.4% ID/g at 48 h. These data indicate that antibody biodistribution and pharmacokinetics can be modulated by a surface detergent and a cytokine, giving decreased exposure to critical organs, and increased uptake into the tumor. This type of manipulation provides an opportunity to optimize radioimmunotherapy. (orig.)

  6. Imaging of soft-tissue sarcomas with indium-111-labeled monoclonal antimyosin Fab fragments

    Energy Technology Data Exchange (ETDEWEB)

    Kairemo, K.J.; Wiklund, T.A.; Liewendahl, K.; Miettinen, M.; Heikkonen, J.J.; Virkkunen, P.J.; Aronen, H.J.; Blomqvist, C.P. (Helsinki Univ. Central Hospital (Finland))

    1990-01-01

    Some soft-tissue sarcomas contain intracellular myosin. We therefore studied the possibility of localizing various soft-tissue sarcomas with {sup 111}In-labeled monoclonal antibody Fab fragments binding specifically to myosin, assuming that damage to the cell membrane could expose intracellular myosin. Nineteen patients with different types of soft-tissue sarcomas were studied. Eighteen patients were found to have abnormal antibody uptakes. Antibody uptake was not observed in an additional patient operated for a benign tumor (gastric leiomyoma). The immunoscintigraphy results were generally in good agreement with those of other radiologic findings (computed tomography, ultrasound, magnetic resonance imaging). Surprisingly, the immunohistochemistry results showed that tumors not stainable for myosin can also be imaged with antimyosin. Thus, the mechanism of antibody uptake does not seem to be related entirely to specific antigen recognition. Irrespective of the exact mechanism for the uptake of labeled antibody this method appears to be useful for localizing soft-tissue sarcomas.

  7. Recent developments in monoclonal antibody radiolabeling techniques

    International Nuclear Information System (INIS)

    Monoclonal antibodies (MAbs) have shown the potential to serve as selective carriers of radionuclides to specific in vivo antigens. Accordingly, there has been an intense surge of research activity in an effort to develop and evaluate MAb-based radiopharmaceuticals for tumor imaging (radioimmunoscintigraphy) and therapy (radioimmunotherapy), as well as for diagnosing nonmalignant diseases. A number of problems have recently been identified, related to the MAbs themselves and to radiolabeling techniques, that comprise both the selectivity and the specificity of the in vivo distribution of radiolabeled MAbs. This paper will address some of these issues and primarily discuss recent developments in the techniques for radiolabeling monoclonal antibodies that may help resolve problems related to the poor in vivo stability of the radiolabel and may thus produce improved biodistribution. Even though many issues are identical with therapeutic radionuclides, the discussion will focus mainly on radioimmunoscintigraphic labels. 78 refs., 6 tabs

  8. Nutrition Facts: Reading the Label

    Science.gov (United States)

    ... My Go4Life Get Free Stuff Be a Partner Nutrition Facts: Reading the Label Reading labels can help ... of information on their labels or packaging about nutrition and food safety. Product dates . You might see ...

  9. Conjugates of monoclonal antibodies and chelating polymers

    International Nuclear Information System (INIS)

    The primary purpose of protein modification with chelating polymers is to prepare monoclonal antibodies labeled with heavy metal isotopes (alpha-, beta-, and gamma-emitting metal and paramagnetic ions for NMR tomography). Conventional binding of metals to proteins via chelating agents directly coupled to proteins does not permit binding of a large number of metal atoms per protein molecule without causing alterations in the specific properties of the protein molecules. On the other hand, metal ion binding to proteins via intermediate chelating polymers should permit binding of several dozens of the metal atoms per protein molecule without affect the specific properties adversely. Moreover, the biodistribution and clearance rates can be regulated by varying the polymer properties. Modified antibodies may be used successfully in nuclear and NMR diagnostic applications and in radiotherapy. Possible applications of this approach shall be demonstrated with monoclonal antibody R11D10 for visualization of acute myocardial infarction. Use of this modification with other monoclonal antibodies is also discussed. The chemistry of protein modification with these polymers is presented

  10. Selection of Recombinant Human Antibodies.

    Science.gov (United States)

    Tomszak, Florian; Weber, Susanne; Zantow, Jonas; Schirrmann, Thomas; Hust, Michael; Frenzel, André

    2016-01-01

    Since the development of therapeutic antibodies the demand of recombinant human antibodies is steadily increasing. Traditionally, therapeutic antibodies were generated by immunization of rat or mice, the generation of hybridoma clones, cloning of the antibody genes and subsequent humanization and engineering of the lead candidates. In the last few years, techniques were developed that use transgenic animals with a human antibody gene repertoire. Here, modern recombinant DNA technologies can be combined with well established immunization and hybridoma technologies to generate already affinity maturated human antibodies. An alternative are in vitro technologies which enabled the generation of fully human antibodies from antibody gene libraries that even exceed the human antibody repertoire. Specific antibodies can be isolated from these libraries in a very short time and therefore reduce the development time of an antibody drug at a very early stage.In this review, we describe different technologies that are currently used for the in vitro and in vivo generation of human antibodies. PMID:27236551

  11. Preparation of monoclonal antibodies against cardiac myosin and some radiolabelling studies

    International Nuclear Information System (INIS)

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

  12. Radioactive labelled orgotein

    International Nuclear Information System (INIS)

    The preparation and use of radioactively labelled orgotein, i.e. water-soluble protein congeners in pure, injectable form, is described. This radiopharmaceutical is useful in scintigraphy, especially for visualization of the kidneys where the orgotein is rapidly concentrated. Details of the processes for labelling bovine orgotein with sup(99m)Tc, 60Co, 125I or 131I are specified. The pharmaceutical preparation of the labelled orgotein for intravenous and parenteral administration is also described. Examples using either sup(99m)TC or 125I-orgotein in scintiscanning dogs' kidneys are given. (UK)

  13. Radioimmunological demonstration of DNA specific antibodies

    International Nuclear Information System (INIS)

    Using 125I chemically labelled denatured (d) and native (n) DNA, specifically binding antibodies were demonstrated in the sera of Lupus erythemathodes patients by means of the Farr technique. (NH4)2SO4 was used to separate the immunologically bound 125I-d-DNA. For 125I-n-DNA the use of a secondary antiserum for the precipitation of the primary immune complex is advantageous. The influence of antigen concentration upon the binding rate was studied. Titre determinations can be made with the proposed method. (author)

  14. Kinetic study of antibody adhesion on a silicon wafer by laser reflectometry

    Science.gov (United States)

    Riquelme, Bibiana D.; Valverde, Juana R.; Rasia, Rodolfo J.

    2003-05-01

    Antibody adhesion kinetic in real time has been studied by laser reflectometry technique. An ellipsometer is used to measure the light intensity reflected by a silicon wafer. Light intensity reflected by the wafer presents a minimum at the pseudo-Brewster angle. Then, the reflectance increases as the antibodies (monoclonal anti- AB) adhere on interface. Mathematical analysis of reflectance curves versus time verifies that the antibody adhesion at the interface follows Langmuir kinetics (Prog. Biomed. Opt. Imaging 1(5) (2000) 19) for low antibody concentrations. Parameters obtained allow to carry out a detailed study of the antibody adsorption and the antigen-antibody interaction. This conduces to development of an optical immunosensor for detection and quantification of soluble antigens, and a novel method for commercial antiserum quality control. This technique does not require labeled antibodies, being also independent of cellular factors. Also, this technique is quicker and sensible than the conventional immunohematology methods.

  15. Substrate coated with receptor and labelled ligand for assays

    International Nuclear Information System (INIS)

    Improvements in the procedures for assaying ligands are described. The assay consists of a polystyrene tube on which receptors are present for both the ligand to be assayed and a radioactively labelled form of the ligand. The receptors on the bottom portion of the tube are also coated with labelled ligands, thus eliminating the necessity for separate addition of the labelled ligand and sample during an assay. Examples of ligands to which this method is applicable include polypeptides, nucleotides, nucleosides and proteins. Specific examples are given in which the ligand to be assayed is digoxin, the labelled form of the ligand is 3-0-succinyl digoxyigenin tyrosine (125I) and the receptor is digoxin antibody. (U.K.)

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

    Science.gov (United States)

    Jennewein, M.; Hermanne, A.; Mason, R. P.; Thorpe, P. E.; Rösch, F.

    2006-12-01

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

  17. Clinical applications of cells labelling

    International Nuclear Information System (INIS)

    Blood cells labelled with radionuclides are reviewed and main applications are described. Red blood cell labelling by both random and specific principle. A table with most important clinical uses, 99mTc labelling of RBC are described pre tinning and in vivo reduction of Tc, in vitro labelling and administration of labelled RBC and in vivo modified technique. Labelled leucocytes with several 99mTc-complex radiopharmaceuticals by in vitro technique and specific monoclonal s for white cells(neutrofiles). Labelled platelets for clinical use and research by in vitro technique and in vivo labelling

  18. Scintigraphic imaging of tumors by in vivo application of biotin-conjugated antibodies and radiolabelled streptavidin

    International Nuclear Information System (INIS)

    Scintigraphic tumor imaging by in vivo application of the streptavidin-biotin system was studied. Binding of anti-cytokeratin antibodies to HeLa carcinoma cells was demonstrated in vitro by immunohistochemical staining and in vivo by scintigraphic imaging using 125I labeled antibodies in nude rats bearing HeLa cell carcinomas. For imaging of tumors with radiolabeled streptavidin, 'cold' biotin-conjugated antiboties were preinjected i.v. In this case, the tumor could be localized after 15 to 60 min whereas it took at least 3 days with the directly labeled antibody. The application of radiolabeled streptavidin was limited by an antibody-independent radioactivity uptake in kidney, liver and spleen. Nevertheless, the short time needed for imaging gives the opportunity of using high energy/short half life isotopes in radioimmunodetection. Furthermore, one single tracer can be used for a wide spectrum of antibodies. (orig.)

  19. Monoclonal antibodies to cell surface antigens of human melanoma

    International Nuclear Information System (INIS)

    The authors have worked with three human melanoma antigens which have been defined by monoclonal mouse antibodies: p97, a glycoprotein that is structurally related to transferrin, a proteoglycan, and a GD3 ganglioside that is slightly different from the GD3 of normal brain. All three antigens can be detected in frozen sections of melanoma, using immunohistological techniques. Antibodies and Fab fragments, specific for either p97 or the proteoglycan antigen, have been radiolabelled with 131I and successfully used for tumor imaging, and Phase I therapeutic trails are underway, using 131I-labelled Fab fragments, specific for p97 or the proteoglycan antigen, to localize a potentially therapeutic dose of radiation into tumors. It may be feasible to use the same monoclonal antibodies, or antibody fragments, as carriers of neutron capturers, such as boron, for possible use in tumor therapy. The initial experiments on this are best carried out by using nude mice (or rats) carrying human melanoma xenografts

  20. Optimization of AFP-radioimmunoassay using Antibody Capture Technique

    International Nuclear Information System (INIS)

    Alpha-fetoprotein (AFP) is a substance produced by the unborn baby. When the neural tube is not properly formed large amounts of AFP pass into the amniotic fluid and reach the mother's blood. By measuring AFP in the mother's blood and amniotic fluid, it is possible to tell whether or not there is a chance that the unborn baby has a neural tube defect. AFP also used as a tumor marker for hepatocellular carcinoma. There are many different techniques for measuring AFP in blood, but the most accurate one is the immunoassay technique. The immunoassays can be classified on the basis of methodology into three classes; (1) the antibody capture assays, (2) the antigen capture assay, (3)the two-antibody sandwich assays. In this present study, the antibody capture assay in which the antigen is attached to a solid support, and labeled antibody is allowed to bind, will be optimized