Minimal contribution of cell-bound antibodies to the immunoscintigraphy of inflamed joints with 99mTc-anti-CD4 monoclonal antibodies

International Nuclear Information System (INIS)

Kinne, R.W.; Palombo-Kinne, E.; Wolski, A.; Wolf, F.; Emmrich, F.; Becker, W.

2002-01-01

Aim: The cellular joint infiltrate in rheumatoid arthritis patients is rich in CD4-positive T-helper lymphocytes and macrophages, rendering anti-CD4 monoclonal antibodies (mAbs) suitable for specific immunoscintigraphy of human/experimental arthritis. Following intravenous injection, however, mAbs are present both in the free form and bound to CD4-positive, circulating monocytes and T-cells. Thus, the present study aimed at analyzing the relative contribution of the free and the cell-bound component to the imaging of inflamed joints in experimental adjuvant arthritis (AA). Methods: AA rat pertioneal macrophages or lymph node T-cells were incubated in vitro with saturating amounts of 99mTc-anti-CD4 mAb (W3/25) and injected i.v. into rats with AA. Results: In vitro release of 99m Tc-anti-CD4 mAb from the cells was limited (on average 1.57%/h for macrophages and 0.84%/h for T-cells). Following i.v. injection, whole body/joints scans and tissue measurements showed only negligible accumulation of radioactivity in inflamed ankle joints (tissue: 0.22 and 0.34% of the injected activity, respectively), whereas the radioactivity was concentrated in liver (tissue: 79% and 71%, respectively), kidney, and urinary bladder. Unlike macrophages, however, anti-CD4 mAb-coated T-cells significantly accumulated in lymphoid organs, the inflamed synovial membrane of the ankle joints, as well as in elbow and knee joints. Conclusion: While the overall contribution of cell-bound mAbs to the imaging of arthritic joints with anti-CD4 mAbs is minimal, differential accumulation of macrophages and T-cells in lymphoid organs and the inflamed synovial membrane indicates preferential migration patterns of these 2 cell populations in arthritic rats. Although only validated for 99m Tc-anti-CD4 mAbs, extrapolation of the results to other anticellular mAbs with similar affinity for their antigen may be possible. (orig.) [de

Evaluation of dry blood spot technique for quantification of an Anti-CD20 monoclonal antibody drug in human blood samples.

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Lin, Yong-Qing; Zhang, Yilu; Li, Connie; Li, Louis; Zhang, Kelley; Li, Shawn

2012-01-01

To evaluate the dried blood spot (DBS) technique in ELISA quantification of larger biomolecular drugs, an anti-CD20 monoclonal antibody drug was used as an example. A method for the quantification of the anti-CD20 drug in human DBS was developed and validated. The drug standard and quality control samples prepared in fresh human blood were spotted on DBS cards and then extracted. A luminescent ELISA was used for quantification of the drug from DBS samples. The assay range of the anti-CD20 drug standards in DBS was 100-2500ng/mL. The intra-assay precision (%CV) ranged from 0.4% to 10.1%, and the accuracy (%Recovery) ranged from 77.9% to 113.9%. The inter assay precision (%CV) ranged from 5.9% to 17.4%, and the accuracy ranged from 81.5% to 110.5%. The DBS samples diluted 500 and 50-fold yielded recovery of 88.7% and 90.7%, respectively. The preparation of DBS in higher and lower hematocrit (53% and 35%) conditions did not affect the recovery of the drug. Furthermore, the storage stability of the anti-CD20 drug on DBS cards was tested at various conditions. It was found that the anti-CD20 drug was stable for one week in DBS stored at room temperature. However, it was determined that the stability was compro]mised in DBS stored at high humidity, high temperature (55°C), and exposed to direct daylight for a week, as well as for samples stored at room temperature and high humidity conditions for a month. Stability did not change significantly in samples that underwent 3 freeze/thaw cycles. Our results demonstrated a successful use of DBS technique in ELISA quantification of an anti-CD20 monoclonal antibody drug in human blood. The stability data provides information regarding sample storage and shipping for future clinical studies. It is, therefore, concluded that the DBS technique is applicable in the quantification of other large biomolecule drugs or biomarkers. Copyright © 2011 Elsevier Inc. All rights reserved.

The feasibility research of galactosyl-anti-mouse CD3 monoclonal antibody being used as carrier of immunotherapy after surgical operation of liver cancer

International Nuclear Information System (INIS)

Li Yunchun; Guan Changtian; Yang Xiaochuan; He Sheng; Jiang Ping; Yuan Lin

2000-01-01

Objective: To probe into the feasibility of galactosyl-anti-mouse CD 3 monoclonal antibody (Gal-Ant-CD 3 McAb) being used as carrier of immunotherapy after surgical operation of liver cancer. Methods: Gal-Ant-CD 3 McAb was prepared by the covalent coupling of anti-mouse CD 3 monoclonal antibody (Ant-CD 3 McAb) with a bifunctional reagent, 2-imino-2-methoxyethyl-1-thio-galactose. After Gal-Ant-CD 3 McAb and Ant-CD 3 McAb were labelled with 131 I or 125 I, the data of biodistribution in mice, and of imaging in rabbit were obtained. After tumour infiltrating lymphocytes (TIL) and Gal-Ant-CD 3 McAb were coupled into Gal-Ant-CD 3 McAb-TIL, its liver taxis and cytotoxic activity against autologous cancer cells were measured in vitro. Results: Gal-Ant-CD 3 McAb had remarkable livertaxis and its uptake in per gram liver was (59.0 +- 2.1)% that was more than two-fold higher than that of Ant-CD 3 McAb. Gal-Ant-CD 3 McAb-TIL had an obvious liver taxis and cytotoxic activity against autologous cancer cells in vitro. Conclusion: Gal-Ant-CD 3 McAb can be used as the carrier of immunotherapy after surgical operation of liver cancer

Evaluation of PLGA containing anti-CTLA4 inhibited endometriosis progression by regulating CD4+CD25+Treg cells in peritoneal fluid of mouse endometriosis model.

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Liu, Qi; Ma, Pingchuan; Liu, Lanxia; Ma, Guilei; Ma, Jingjing; Liu, Xiaoxuan; Liu, Yijin; Lin, Wanjun; Zhu, Yingjun

2017-01-01

Our study investigated poly(lactic-co-glycolic acid) (PLGA) as protein delivery vehicles encapsulate CTLA-4-antibody (anti-CTLA-4) which is essential for CD4+CD25+Treg cells suppressive function exposing superior potential for inhibiting endometriosis progress in mouse model than single anti-CTLA-4. Anti-CTLA-4 loaded PLGA combined to ligands CTLA-4 in surface of CD4+CD25+Treg cells which distributed in peritoneal fluid of mouse endometriosis model. The particle size, zeta potential of the anti-CTLA-4 loaded nanoparticles was detected by dynamic light scattering. Morphology of nanoparticles was evaluated by transmission electron microscopy (TEM). Confocal laser scanning microscopy (CLSM) indicated distribution of anti-CTLA-4 with PLGA or without in peritoneal fluid. Cumulative anti-CTLA-4 release from nanoparticles was evaluated by Micro BCA assay. The percentage of CD4+CD25+Treg cells in peritoneal fluid was demonstrated by flow cytometer. In vitro experiment we co-culture ectopic endometrial cells (EEC) with isolated CD4+CD25+Treg cells in peritoneal fluid (PF), proliferation and invasion of ectopic endometrial cells (EEC) was measured by BrdU ELISA assay and Matrigel invasion assay. In comparison with anti-CTLA-4 without nanoparticles, the bioconjugates PLGA/anti-CTLA-4 were tolerated in peritoneal fluid with a controlled release of anti-CTLA-4 in 3, 7, 14days. Moreover, PLGA/anti-CTLA-4 had superior protective regulation ability to reduce level of CD4+CD25+Treg cells in peritoneal fluid. Most strikingly, in vitro experiment, PLGA/anti-CTLA-4 exhibited better ability in inhibiting proliferation and invasion of ectopic endometrial cells in co-culture system compared with anti-CTLA-4. Progressively, PLGA/anti-CTLA-4 had better suppressive activity to inhibited IL-10 and TGF-beta secreted by CD4+CD25+Treg cells which indicating that PLGA/anti-CTLA-4 suppressed cells proliferation and invasion through reduced IL-10 and TGF-beta production. Thus, PLGA/anti-CTLA-4 may

Short-term azithromycin treatment promotes cornea allograft survival in the rat.

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Wacker, Katrin; Denker, Sophy; Hildebrand, Antonia; Eberwein, Philipp; Reinhard, Thomas; Schwartzkopff, Johannes

2013-01-01

Any inflammatory response following corneal transplantation may induce rejection and irreversible graft failure. The purpose of this study is to analyze the anti-inflammatory effect of azithromycin (AZM) following experimental keratoplasty in rats. Corneal transplants were performed between Fisher-donor and Lewis-recipient rats. Recipients were postoperatively treated three times daily with AZM, miglyol, ofloxacin or dexamethasone eye drops. As an additional control, AZM was applied following syngeneic keratoplasty. Furthermore, short-term treatments with AZM for seven days perioperatively or with AZM only three days prior to the transplantation were compared to appropriate controls. All transplants were monitored clinically for opacity, edema, and vascularization. Infiltrating CD45(+), CD4(+), CD8(+), CD25(+), CD161(+) and CD163(+) cells were quantified via immunohistochemistry. AZM significantly promoted corneal graft survival compared with miglyol or ofloxacin treatment. This effect was comparable to topical dexamethasone. No adverse AZM effect was observed. Histology confirmed a significant reduction of infiltrating leukocytes. The short-term application of AZM for three days prior to transplantation or for seven days perioperatively reduced corneal graft rejection significantly compared with the controls. Along with antibiotic properties, topical AZM has a strong anti-inflammatory effect. Following keratoplasty, this effect is comparable to topical dexamethasone without the risk of steroid-induced adverse effects. Short-term treatment with AZM three days prior to the transplantation was sufficient to promote graft survival in the rat keratoplasty model. We therefore suggest further assessing the anti-inflammatory function of topical AZM following keratoplasty in humans.

Short-term azithromycin treatment promotes cornea allograft survival in the rat.

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Katrin Wacker

Full Text Available Any inflammatory response following corneal transplantation may induce rejection and irreversible graft failure. The purpose of this study is to analyze the anti-inflammatory effect of azithromycin (AZM following experimental keratoplasty in rats.Corneal transplants were performed between Fisher-donor and Lewis-recipient rats. Recipients were postoperatively treated three times daily with AZM, miglyol, ofloxacin or dexamethasone eye drops. As an additional control, AZM was applied following syngeneic keratoplasty. Furthermore, short-term treatments with AZM for seven days perioperatively or with AZM only three days prior to the transplantation were compared to appropriate controls. All transplants were monitored clinically for opacity, edema, and vascularization. Infiltrating CD45(+, CD4(+, CD8(+, CD25(+, CD161(+ and CD163(+ cells were quantified via immunohistochemistry.AZM significantly promoted corneal graft survival compared with miglyol or ofloxacin treatment. This effect was comparable to topical dexamethasone. No adverse AZM effect was observed. Histology confirmed a significant reduction of infiltrating leukocytes. The short-term application of AZM for three days prior to transplantation or for seven days perioperatively reduced corneal graft rejection significantly compared with the controls.Along with antibiotic properties, topical AZM has a strong anti-inflammatory effect. Following keratoplasty, this effect is comparable to topical dexamethasone without the risk of steroid-induced adverse effects. Short-term treatment with AZM three days prior to the transplantation was sufficient to promote graft survival in the rat keratoplasty model. We therefore suggest further assessing the anti-inflammatory function of topical AZM following keratoplasty in humans.

Generation and Characterization of Anti-CD34 Monoclonal Antibodies that React with Hematopoietic Stem Cells

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Aghebati Maleki, Leili; Majidi, Jafar; Baradaran, Behzad; Movassaghpour, Aliakbar; Abdolalizadeh, Jalal

2014-01-01

CD34 is a type I membrane protein with a molecular mass of approximately 110 kDa. This antigen is associated with human hematopoietic progenitor cells and is a differentiation stage-specific leukocyte antigen. In this study we have generated and characterized monoclonal antibodies (mAbs) directed against a CD34 marker. Mice were immunized with two keyhole lympet hemocyanin (KLH)-conjugated CD34 peptides. Fused cells were grown in hypoxanthine, aminopterine and thymidine (HAT) selective medium and cloned by the limiting dilution (L.D) method. Several monoclones were isolated by three rounds of limited dilutions. From these, we chose stable clones that presented sustained antibody production for subsequent characterization. Antibodies were tested for their reactivity and specificity to recognize the CD34 peptides and further screened by enzyme-linked immunosorbent assay (ELISA) and Western blotting analyses. One of the mAbs (3D5) was strongly reactive against the CD34 peptide and with native CD34 from human umbilical cord blood cells (UCB) in ELISA and Western blotting analyses. The results have shown that this antibody is highly specific and functional in biomedical applications such as ELISA and Western blot assays. This monoclonal antibodies (mAb) can be a useful tool for isolation and purification of human hematopoietic stem cells (HSCs). PMID:24611141

Therapeutic effects of anti-CD115 monoclonal antibody in mouse cancer models through dual inhibition of tumor-associated macrophages and osteoclasts.

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Laetitia Fend

Full Text Available Tumor progression is promoted by Tumor-Associated Macrophages (TAMs and metastasis-induced bone destruction by osteoclasts. Both myeloid cell types depend on the CD115-CSF-1 pathway for their differentiation and function. We used 3 different mouse cancer models to study the effects of targeting cancer host myeloid cells with a monoclonal antibody (mAb capable of blocking CSF-1 binding to murine CD115. In mice bearing sub-cutaneous EL4 tumors, which are CD115-negative, the anti-CD115 mAb depleted F4/80(+ CD163(+ M2-type TAMs and reduced tumor growth, resulting in prolonged survival. In the MMTV-PyMT mouse model, the spontaneous appearance of palpable mammary tumors was delayed when the anti-CD115 mAb was administered before malignant transition and tumors became palpable only after termination of the immunotherapy. When administered to mice already bearing established PyMT tumors, anti-CD115 treatment prolonged their survival and potentiated the effect of chemotherapy with Paclitaxel. As shown by immunohistochemistry, this therapeutic effect correlated with the depletion of F4/80(+CD163(+ M2-polarized TAMs. In a breast cancer model of bone metastasis, the anti-CD115 mAb potently blocked the differentiation of osteoclasts and their bone destruction activity. This resulted in the inhibition of cancer-induced weight loss. CD115 thus represents a promising target for cancer immunotherapy, since a specific blocking antibody may not only inhibit the growth of a primary tumor through TAM depletion, but also metastasis-induced bone destruction through osteoclast inhibition.

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

DEFF Research Database (Denmark)

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

1988-01-01

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

Cloning and expression of canine CD25 for validation of an anti-human CD25 antibody to compare T regulatory lymphocytes in healthy dogs and dogs with osteosarcoma.

Science.gov (United States)

Rissetto, K C; Rindt, H; Selting, K A; Villamil, J A; Henry, C J; Reinero, C R

2010-05-15

T regulatory cells (Tregs) are a unique subset of T helper cells that serve to modify/inhibit effector cells of the immune system and thus are essential to prevent autoimmunity. Overzealous Treg activity may contribute to impaired immune responses to cancer. Tregs can be phenotypically identified by proteins expressed on the cell surface (CD4 and CD25) and inside the cell (forkhead box3 (FoxP3)), although in dogs, no anti-canine CD25 antibody exists. We hypothesized that a mouse anti-human CD25 antibody definitively recognizes the canine protein and can be used to identify Tregs in dogs. We describe cloning and transfection of the canine CD25 gene into human HeLa cells with subsequent expression of the canine protein on the cell surface detected using an anti-human CD25 antibody in a flow cytometric assay. Validation of this antibody was used to identify CD4+CD25+FoxP3+ Tregs in 39 healthy dogs and 16 dogs with osteosarcoma (OSA). Results were expressed in five different ways and showed significantly fewer %CD4+CD25+ T lymphocytes expressing FoxP3 in blood of older dogs (>/=7 years) compared with the other two age groups (<2 and 2-6 years) (p<0.001) and fewer %CD4+CD25+FoxP3+ Tregs in the tumor draining lymph nodes of OSA patients compared to the unrelated lymph node (p=0.049). However, there was no significant difference in % Tregs in the peripheral blood or lymph nodes between the control dogs and those with OSA. While the CD25 antibody can be successfully used in a flow cytometric assay to identify Tregs, this study does not support clinical utility of phenotypic recognition of Tregs in dogs with OSA. Copyright 2010 Elsevier B.V. All rights reserved.

Safety and efficacy of ofatumumab, a fully human monoclonal anti-CD20 antibody, in patients with relapsed or refractory B-cell chronic lymphocytic leukemia

DEFF Research Database (Denmark)

Coiffier, Bertrand; Lepretre, Stéphane; Pedersen, Lars Møller

2008-01-01

Safety and efficacy of the fully human anti-CD20 monoclonal antibody, ofatumumab, was analyzed in a multicenter dose-escalating study including 33 patients with relapsed or refractory chronic lymphocytic leukemia. Three cohorts of 3 (A), 3 (B), and 27 (C) patients received 4, once weekly, infusio...

Mass-Production and Characterization of Anti-CD20 Monoclonal Antibody in Peritoneum of Balb/c Mice

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Leili Aghebati

2013-02-01

Full Text Available Purpose: Monoclonal antibodies are important tools are used in basic research as well as, in diagnosis, imaging and treatment of immunodeficiency diseases, infections and cancers. The purpose of this study was to produce large scale of monoclonal antibody against CD20 in order to diagnostic application in leukemia and lymphomas disorders. Methods: Hybridoma cells that produce monoclonal antibody against human CD20 were administered into the peritoneum of the Balb/c mice which have previously been primed with 0.5 ml Pristane. After twelve days, approximately 7 ml ascetic fluid was harvested from the peritoneum of each mouse. Evaluation of mAb titration was assessed by ELISA method. In the present study, we describe a protocol for large scale production of MAbs. Results: We prepared monoclonal antibodies (mAbs with high specificity and sensitivity against human CD20 by hybridoma method and characterized them by ELISA. The subclass of antibody was IgG2a and its light chain was kappa. Ascetic fluid was purified by Protein-A Sepharose affinity chromatography and the purified monoclonal antibody was conjugated with FITC and Immunofluorescence was done for confirming the specific binding. Conclusion: The conjugated monoclonal antibody could have application in diagnosis B-cell lymphomas, hairy cell leukemia, B-cell chronic lymphocytic leukemia, and melanoma cancer stem cells.

Mass-Production and Characterization of Anti-CD20 Monoclonal Antibody in Peritoneum of Balb/c Mice

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Sineh sepehr, Koushan; Baradaran, Behzad; Majidi, Jafar; Abdolalizadeh, Jalal; Aghebati, leili; Zare Shahneh, Fatemeh

2013-01-01

Purpose: Monoclonal antibodies are important tools are used in basic research as well as, in diagnosis, imaging and treatment of immunodeficiency diseases, infections and cancers. The purpose of this study was to produce large scale of monoclonal antibody against CD20 in order to diagnostic application in leukemia and lymphomas disorders. Methods: Hybridoma cells that produce monoclonal antibody against human CD20 were administered into the peritoneum of the Balb/c mice which have previously been primed with 0.5 ml Pristane. After twelve days, approximately 7 ml ascetic fluid was harvested from the peritoneum of each mouse. Evaluation of mAb titration was assessed by ELISA method. In the present study, we describe a protocol for large scale production of MAbs. Results: We prepared monoclonal antibodies (mAbs) with high specificity and sensitivity against human CD20 by hybridoma method and characterized them by ELISA. The subclass of antibody was IgG2a and its light chain was kappa. Ascetic fluid was purified by Protein-A Sepharose affinity chromatography and the purified monoclonal antibody was conjugated with FITC and Immunofluorescence was done for confirming the specific binding. Conclusion: The conjugated monoclonal antibody could have application in diagnosis B-cell lymphomas, hairy cell leukemia, B-cell chronic lymphocytic leukemia, and melanoma cancer stem cells. PMID:24312821

Large Scale Generation and Characterization of Anti-Human CD34 Monoclonal Antibody in Ascetic Fluid of Balb/c Mice

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Aghebati Maleki, Leili; Majidi, Jafar; Baradaran, Behzad; Abdolalizadeh, Jalal; Kazemi, Tohid; Aghebati Maleki, Ali; Sineh sepehr, Koushan

2013-01-01

Purpose: Monoclonal antibodies or specific antibodies are now an essential tool of biomedical research and are of great commercial and medical value. The purpose of this study was to produce large scale of monoclonal antibody against CD34 in order to diagnostic application in leukemia and purification of human hematopoietic stem/progenitor cells. Methods: For large scale production of monoclonal antibody, hybridoma cells that produce monoclonal antibody against human CD34 were injected into t...

A novel monoclonal anti-CD81 antibody produced by genetic immunization efficiently inhibits Hepatitis C virus cell-cell transmission.

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Isabel Fofana

Full Text Available Hepatitis C virus (HCV infection is a challenge to prevent and treat because of the rapid development of drug resistance and escape. Viral entry is required for initiation, spread, and maintenance of infection, making it an attractive target for antiviral strategies.Using genetic immunization, we produced four monoclonal antibodies (mAbs against the HCV host entry factor CD81. The effects of antibodies on inhibition of HCV infection and dissemination were analyzed in HCV permissive human liver cell lines.The anti-CD81 mAbs efficiently inhibited infection by HCV of different genotypes as well as a HCV escape variant selected during liver transplantation and re-infecting the liver graft. Kinetic studies indicated that anti-CD81 mAbs target a post-binding step during HCV entry. In addition to inhibiting cell-free HCV infection, one antibody was also able to block neutralizing antibody-resistant HCV cell-cell transmission and viral dissemination without displaying any detectable toxicity.A novel anti-CD81 mAb generated by genetic immunization efficiently blocks HCV spread and dissemination. This antibody will be useful to further unravel the role of virus-host interactions during HCV entry and cell-cell transmission. Furthermore, this antibody may be of interest for the development of antivirals for prevention and treatment of HCV infection.

Comparison of the Number of Peripheral Blood CD4+CD25+ T Cells in Unexplained Recurrent Spontaneous Abortion Patients with Normal Pregnant Women

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M Eslami

2011-05-01

Full Text Available Introduction: Undoubtedly, reproduction is a necessity for survival and successful pregnancy is an immunological paradox. In the present study, we investigated the proportional changes of CD4+CD25bright T cells, CD4+CD25dim T cells in peripheral blood in unexplained recurrent spontaneous abortions (URSA and compared it with normal pregnant women by antibody monoclonal method. Methods: The study group comprised of women with miscarriages of unexplained etiology who had normal karyotypes, anticardiolipin antibodies, prolactin levels and normal spousal spermograms. They did not have polycystic ovaries and also did not receive any drugs at the time of the study. PBLs lymphocytes were isolated, then FITC-conjugated and anti-CD4 and PE-conjugated anti-CD25 antibody levels were measured. Then results of the study and control group were analyzed and compared. Results: The absolute number of CD25 bright cells in the CD4‏+T cells in peripheral blood was statistically significantly lower in the study group as compared to the control group(P=0.000. The absolute number of CD4+CD25dimT cells in peripheral blood was statistically significantly higher in the study group as compared to the control group (P=0.000. Conclusion: As decrease in the number of CD4+CD25+Tcells or their functional deficiency may be linked with miscarriage, CD4+CD25+‏ Tells could serve as a novel biomarker for monitoring in URSA patients, but more studies are needed in this field.

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

International Nuclear Information System (INIS)

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

2008-01-01

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

Down-regulation of FcεRI-mediated CD63 basophil response during short-term VIT determined venom-nonspecific desensitization.

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Nina Čelesnik Smodiš

Full Text Available BACKGROUND: We recently showed a desensitization of FcεRI-mediated basophil response after short-term VIT. Our aim was to evaluate the allergen specificity of this desensitization. METHODS: In 11 Hymenoptera-venom double positive subjects, basophil threshold sensitivity (CD-sens to anti-FcεRI, honeybee, and Vespula venom was assessed at the beginning and just before the first maintenance dose (MD of single ultra-rush VIT. In some patients we also monitored CD-sens to rApi m 1 and/or rVes v 5 or other co-sensitizations (i.e., grass pollen. In additional 7 patients, basophils were stripped and sensitized with house dust mite (HDM IgEs at the same time points. RESULTS: We demonstrated a marked reduction of CD-sens to anti-FcεRI and VIT-specific venom before the first MD in all 18 subjects included. Furthermore, in 10 out of 11 double positive subjects, a significant and comparable decrease before the first MD was also evident for non-VIT venom; this nonspecific decrease was further supported by the opposite recombinant species-specific major allergen. In one subject with additional grass pollen allergy, a decrease of CD-sens to grass allergen was also demonstrated. Similarly, in 7 cases of patients with passively HDM-sensitized basophils, a significant reduction of CD-sens was also evident to de novo sensitized HDM allergen. CONCLUSIONS: Short-term VIT induced basophil desensitization to VIT-specific as well as to VIT-nonspecific venom. As opposed to long-term VIT, which induces venom-specific changes, the effect of short-term VIT seems to be venom-nonspecific.

[{sup 177}Lu]DOTA-anti-CD20: Labeling and pre-clinical studies

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Audicio, Paola F., E-mail: paudicio@cin.edu.u [Departamento de Radiofarmacia, Centro de Investigaciones Nucleares, Facultad de Ciencias, Universidad de la Republica, Mataojo 2055, 11400 Montevideo (Uruguay); Castellano, Gustavo, E-mail: gcas@famaf.unc.edu.a [FaMAF, Universidad Nacional de Cordoba, Ciudad Universitaria, 5016 Cordoba (Argentina); Tassano, Marcos R.; Rezzano, Maria E.; Fernandez, Marcelo [Departamento de Radiofarmacia, Centro de Investigaciones Nucleares, Facultad de Ciencias, Universidad de la Republica, Mataojo 2055, 11400 Montevideo (Uruguay); Riva, Eloisa [Clinica Hematologica ' Prof. Dra. L. Diaz' , Hospital de Clinicas. Av. Italia. sn, Montevideo (Uruguay); Robles, Ana; Cabral, Pablo; Balter, Henia; Oliver, Patricia [Departamento de Radiofarmacia, Centro de Investigaciones Nucleares, Facultad de Ciencias, Universidad de la Republica, Mataojo 2055, 11400 Montevideo (Uruguay)

2011-07-15

Anti-CD20 (Rituximab), a specific chimeric monoclonal antibody used in CD20-positive Non-Hodgkin's Lymphoma, was conjugated to a bifunctional quelate (DOTA) and radiolabeled with {sup 177}Lu through a simple method. [{sup 177}Lu]-DOTA-anti-CD20 was obtained with a radiochemical purity higher than 97%, and showed good chemical and biological stability, maintaining its biospecificity to CD20 antigens. Monte Carlo simulation showed high doses deposited on a spheroid tumor mass model. This method seems to be an appropriate alternative for the production of [{sup 177}Lu]-DOTA-anti-CD20 as therapeutic radiopharmaceutical.

Large Scale Generation and Characterization of Anti-Human CD34 Monoclonal Antibody in Ascetic Fluid of Balb/c Mice

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Koushan Sineh sepehr

2013-02-01

Full Text Available Purpose: Monoclonal antibodies or specific antibodies are now an essential tool of biomedical research and are of great commercial and medical value. The purpose of this study was to produce large scale of monoclonal antibody against CD34 in order to diagnostic application in leukemia and purification of human hematopoietic stem/progenitor cells. Methods: For large scale production of monoclonal antibody, hybridoma cells that produce monoclonal antibody against human CD34 were injected into the peritoneum of the Balb/c mice which have previously been primed with 0.5 ml Pristane. 5 ml ascitic fluid was harvested from each mouse in two times. Evaluation of mAb titration was assessed by ELISA method. The ascitic fluid was examined for class and subclasses by ELISA mouse mAb isotyping Kit. mAb was purified from ascitic fluid by affinity chromatography on Protein A-Sepharose. Purity of monoclonal antibody was monitored by SDS -PAGE and the purified monoclonal antibody was conjugated with FITC. Results: Monoclonal antibodies with high specificity and sensitivity against human CD34 by hybridoma technology were prepared. The subclass of antibody was IgG1 and its light chain was kappa. Conclusion: The conjugated monoclonal antibody could be a useful tool for isolation, purification and characterization of human hematopoietic stem cells.

Large Scale Generation and Characterization of Anti-Human CD34 Monoclonal Antibody in Ascetic Fluid of Balb/c Mice

Science.gov (United States)

Aghebati Maleki, Leili; Majidi, Jafar; Baradaran, Behzad; Abdolalizadeh, Jalal; Kazemi, Tohid; Aghebati Maleki, Ali; Sineh sepehr, Koushan

2013-01-01

Purpose: Monoclonal antibodies or specific antibodies are now an essential tool of biomedical research and are of great commercial and medical value. The purpose of this study was to produce large scale of monoclonal antibody against CD34 in order to diagnostic application in leukemia and purification of human hematopoietic stem/progenitor cells. Methods: For large scale production of monoclonal antibody, hybridoma cells that produce monoclonal antibody against human CD34 were injected into the peritoneum of the Balb/c mice which have previously been primed with 0.5 ml Pristane. 5 ml ascitic fluid was harvested from each mouse in two times. Evaluation of mAb titration was assessed by ELISA method. The ascitic fluid was examined for class and subclasses by ELISA mouse mAb isotyping Kit. mAb was purified from ascitic fluid by affinity chromatography on Protein A-Sepharose. Purity of monoclonal antibody was monitored by SDS -PAGE and the purified monoclonal antibody was conjugated with FITC. Results: Monoclonal antibodies with high specificity and sensitivity against human CD34 by hybridoma technology were prepared. The subclass of antibody was IgG1 and its light chain was kappa. Conclusion: The conjugated monoclonal antibody could be a useful tool for isolation, purification and characterization of human hematopoietic stem cells. PMID:24312838

Standardization of methodology to derivatization and radiolabeling of the anti-CD20 monoclonal antibody from bifunctional chelator DOTA-NHS-Ester

International Nuclear Information System (INIS)

Massicano, Adriana V.F.; Akanji, Akinkunmi G.; Santos, Josefina S.; Pujatti, Priscilla B.; Couto, Renata M.; Massicano, Felipe; Araujo, Elaine Bortoleti de

2009-01-01

Lymphomas are cancers of the lymphatic system, being the most common the non-Hodgkin lymphoma (NHL). The Radioimmunotherapy (RIT), that increase the cytotoxic effect of monoclonal antibodies (mAb), therefore labeling these Mab with different radioisotopes. RIT combines the specificity of the antibody and the toxicity of the radionuclides. The mAb anti-CD20 is used for treatment of relapse or refractory NHL. The labeling of anti- CD20 with 177 Lu, requires a bifunctional chelating agent that is designed to make a 'connect bridge' between the mAb and the radionuclide. The incorporation of the chelating group in mAb structure is called derivatization. The aim of this work is to study the derivatization of anti-CD20 antibody with DOTA-NHS-ester chelating group and labeling parameters to produce 177 Lu-DOTA-Anti CD20. Five milligrams of anti-CD20 were purified by dialysis against phosphate buffer pH 8.0 and derivatized with DOTA-NHS-ester in 1:250, 1:500 and 1:1000 molar ratios. The reaction was conducted for 1 hour in gently mixing at room temperature and remained under refrigeration for 48 hours. The reaction mixture was purified in gel column Sephadex G-50 ; the aliquots that presented greater protein concentration, were mixed and concentrated. The purified antibody conjugated was added to 111-185MBq (3-5mCi) of 177 LuCl3 diluted in 0.4 M acetate buffer pH 5.5. Radiochemical purity was less than 95% in all the molar ratios, indicating necessity of the purification after the labeling. The mAb derivatized showed stable when stored for to 1 month to 4 deg C and 4 days at -20 deg C. (author)

The biological characteristics of anti-CD71 mouse/human chimeric antibody

International Nuclear Information System (INIS)

Wang Shuo; Jiang Lin; Lei Ping; Zhu Huifen; Shen Guanxin; Cui Wuren; Wang Yanggong

2002-01-01

Objective: To study the biological characteristics of an anti-CD71 mouse/human chimeric antibody (D2C). Methods: Analysis of the chimeric Ab production in culture supernatant was made by the standard concentration curve method with ELISA. The antibody was purified by DEAE-Sephredax-A50 ion-exchange chromatography and was confirmed by SDS-PAGE. The competition inhibition studies for binding to the same epitope on CD71 were performed between the chimeric Ab(D2C) in the culture supernatant was about 0.5-5 μg/ml in 5-day cultures when seeded at 1 x 10 5 cells/5ml compared with 12.5-25 μg/ml in the supernatant from their parental monoclonal Ab(7579). The purified chimeric Ab(D2C) from mouse ascetics was 1-2 mg/ml. The SDS-PAGE analysis of purified chimeric Ab(D2C) with discontinuous system confirmed two protein bands of 55 kDa and 25 kDa. It was clear that both chimeric Ab(D2C) and murine monoclonal Ab (7579) compete effectively to join the same epitope of CD71 each other. The chimeric antibody's affinity constant (Ka), quantitated by Scatchard analysis, is about 9.34-9.62 x 10 9 L/mol. Conclusion: The chimeric Ab(D2C) produced from the transfectomas is stable. The binding capacity of the chimeric Ab(D2C) to the antigen (CD71) was retained

Radiolabeling of anti-CD20 with Re0-188: liquid kit

International Nuclear Information System (INIS)

Dias, Carla Roberta; Osso Junior, Joao Alberto

2007-01-01

Radioimmunotherapy uses the targeting features of monoclonal antibody to deliver radiation from an attached radionuclide. The radionuclide 188 Re is currently produced from the father nuclide 188 W through a transportable generator system. Because of its easy availability and suitable nuclear properties (E βMAX =2.1 MeV, t 1/2 =16.9 h, E γ =155 keV), this radionuclide is considered an attractive candidate for application as therapeutic agents and could be conveniently utilized for imaging and dosimetric purposes. The objective of this work is the optimization of radiolabeling of anti-CD20 with 188 Re using a liquid formulation. Anti-CD20 was reduced by incubation with 2-ME and purified over a PD-10 column. The number of resulting free SH was assayed with Ellman's reagent. Optimization of radiolabeling was achieved by varying parameters: antibody mass, reducing agent, reaction time and 188 Re volume in the liquid kit. Radiochemical purity of 188 Re-anti-CD20 was evaluated. An average of 12 SH groups per mol in the reductions was found. The best labeling efficiency (> 93%) was achieved in the following conditions: 1 mg anti-CD20; 82.8 mg sodium tartrate; 1 mg SnCl 2 ; 0.25 mg gentisic acid, 1 mL 188 Re and reaction time of 1 hour at room temperature. (author)

Anti-Human Endoglin (hCD105) Immunotoxin-Containing Recombinant Single Chain Ribosome-Inactivating Protein Musarmin 1.

Science.gov (United States)

Barriuso, Begoña; Antolín, Pilar; Arias, F Javier; Girotti, Alessandra; Jiménez, Pilar; Cordoba-Diaz, Manuel; Cordoba-Diaz, Damián; Girbés, Tomás

2016-06-10

Endoglin (CD105) is an accessory component of the TGF-β receptor complex, which is expressed in a number of tissues and over-expressed in the endothelial cells of tumor neovasculature. Targeting endoglin with immunotoxins containing type 2 ribosome-inactivating proteins has proved an effective tool to reduce blood supply to B16 mice tumor xenografts. We prepared anti-endoglin immunotoxin (IT)-containing recombinant musarmin 1 (single chain ribosome-inactivating proteins) linked to the mouse anti-human CD105 44G4 mouse monoclonal antibody via N-succinimidyl 3-(2-pyridyldithio) propionate (SPDP). The immunotoxin specifically killed L929 fibroblast mouse cells transfected with the short form of human endoglin with IC50 values in the range of 5 × 10(-10) to 10(-9) M.

Radiolabeled Humanized Anti-CD3 Monoclonal Antibody Visilizumab for Imaging Human T-Lymphocytes

NARCIS (Netherlands)

Malviya, Gaurav; D'Alessandria, Calogero; Bonanno, Elena; Vexler, Vladimir; Massari, Roberto; Trotta, Carlo; Scopinaro, Francesco; Dierckx, Rudi; Signore, Alberto

2009-01-01

Visilizumab is an IgG(2) humanized monoclonal antibody (mAb) characterized by non-Fc gamma R binding and specific to the CD3 antigen, expressed on more than 95% of circulating resting T-lymphocytes and on activated T-lymphocytes homing in inflamed tissues. We hypothesized that the use of a

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

International Nuclear Information System (INIS)

Akanji, Akinkunmi Ganiyu

2006-01-01

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

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

International Nuclear Information System (INIS)

Akanji, Akinkunmi Ganiyu

2006-01-01

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

Short- and long-term effects of T-cell modulating agents in experimental autoimmunity

International Nuclear Information System (INIS)

Mellergaard, Johan; Havarinasab, Said; Hultman, Per

2004-01-01

Due to the easy and reliable induction of a disease condition with many of the features present in human autoimmunity, mercury-induced autoimmunity (mHgAI) in rodents is a favourable autoimmune model. Genetically susceptible (H-2 s ) mice develop in response to mercury (Hg) a systemic autoimmune condition with antinucleolar antibodies (ANoA) targeting the protein fibrillarin, transient polyclonal B-cell activation, hyperimmunoglobulinemia, and systemic immune-complex (IC) deposits. In order to study the short- and long-term effects of treatment with immunomodulating agents on the disease parameters in HgAI, groups of B10.S (H-2 s ) mice were given 6 mg HgCl 2 /l drinking water for 22 weeks. Three weeks initial treatment with cyclosporin A (CyA), a high dose of tacrolimus (HD tacrolimus), or anti-CD4 monoclonal antibody (a-CD4) inhibited induction of ANoA and IC deposit by Hg. This effect persisted for the subsequent 19 weeks when the mice were only treated with Hg. Initial treatment with anti-IL-4 monoclonal antibody (a-IL-4) for 3 weeks inhibited induction of IgE and IC deposits by Hg, but not ANoA. However, subsequent treatment with Hg without a-IL-4 for 19 weeks induced IC deposits. The T-cell modulating agents aggravated some of the HgAI disease parameters: a-CD4 stimulated the polyclonal B-cell activation, a-IL-4 increased the IgG antichromatin antibody response, and a low dose of tacrolimus (LD tacrolimus) enhanced the ANoA, the polyclonal B-cell activation, and the IC deposits. We conclude that a short initial treatment with a-CD4 or CyA efficiently protects against induction of systemic autoimmunity for an extended period of time. However, some of the T-cell modulating agents, especially a low dose of tacrolimus, aggravate autoimmune manifestations not only during ongoing treatment, but also after treatment with these agents has ceased

[Regulatory B cells activated by CpG-ODN combined with anti-CD40 monoclonal antibody inhibit CD4(+)T cell proliferation].

Science.gov (United States)

Wang, Keng; Tao, Lei; Su, Jianbing; Zhang, Yueyang; Zou, Binhua; Wang, Yiyuan; Li, Xiaojuan

2016-09-01

Objective To observe the immunosuppressive function of regulatory B cells (Bregs) in vitro after activated by CpG oligodeoxynucleotide (CpG-ODN) and anti-CD40 mAb. Methods Mice splenic CD5(+)CD1d(high)B cells and CD5(-)CD1d(low)B cells were sorted by flow cytometry. These B cells were first stimulated with CpG-ODN combined with anti-CD40 mAb for 24 hours, and then co-cultured with purified CD4(+)T cells. The interleukin 10 (IL-10) expression in the activated Bregs and other B cell subset, as well as the proliferation and interferon γ (IFN-γ) expression in the CD4(+) T cells activated by anti-CD3 mAb plus anti-CD28 mAb were determined by flow cytometry. Results CD5(+)CD1d(high) B cells activated by CpG-ODN plus anti-CD40 mAb blocked the up-regulated CD4(+)T proliferation and significantly reduced the IFN-γ level. At the same time, activated CD5(-)CD1d(low)B cells showed no inhibitory effect on CD4(+)T cells. Further study revealed that IL-10 expression in the CD5(+)CD1d(high) B cells were much higher than that in the CD5(-)CD1d(low)B cells after stimulated with CpG-ODN combined with anti-CD40 mAb for 24 hours. Conclusion CD5(+)CD1d(high) B cells activated by CpG-ODN combined with anti-CD40 mAb have immune inhibitory effects on CD4(+)T cell activation in vitro , which possibly due to IL-10 secretion.

Immunization of chickens with an agonistic monoclonal anti-chicken CD40 antibody-hapten complex: rapid and robust IgG response induced by a single subcutaneous injection.

Science.gov (United States)

Chen, Chang-Hsin; Abi-Ghanem, Daad; Waghela, Suryakant D; Chou, Wen-Ko; Farnell, Morgan B; Mwangi, Waithaka; Berghman, Luc R

2012-04-30

Producing diagnostic antibodies in chicken egg yolk represents an alternate animal system that offers many advantages including high productivity at low cost. Despite being an excellent counterpart to mammalian antibodies, chicken IgG from yolk still represents an underused resource. The potential of agonistic monoclonal anti-CD40 antibodies (mAb) as a powerful immunological adjuvant has been demonstrated in mammals, but not in chickens. We recently reported an agonistic anti-chicken CD40 mAb (designated mAb 2C5) and showed that it may have potential as an immunological adjuvant. In this study, we examined the efficacy of targeting a short peptide to chicken CD40 [expressed by the antigen-presenting cells (APCs)] in enhancing an effective IgG response in chickens. For this purpose, an immune complex consisting of one streptavidin molecule, two directionally biotinylated mAb 2C5 molecules, and two biotinylated peptide molecules was produced. Chickens were immunized subcutaneously with doses of this complex ranging from 10 to 90 μg per injection once, and relative quantification of the peptide-specific IgG response showed that the mAb 2C5-based complex was able to elicit a strong IgG response as early as four days post-immunization. This demonstrates that CD40-targeting antigen to chicken APCs can significantly enhance antibody responses and induce immunoglobulin isotype-switching. This immunization strategy holds promise for rapid production of hapten-specific IgG in chickens. Copyright © 2012 Elsevier B.V. All rights reserved.

Chimeric antigen receptor (CAR-specific monoclonal antibody to detect CD19-specific T cells in clinical trials.

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Bipulendu Jena

Full Text Available Clinical trials targeting CD19 on B-cell malignancies are underway with encouraging anti-tumor responses. Most infuse T cells genetically modified to express a chimeric antigen receptor (CAR with specificity derived from the scFv region of a CD19-specific mouse monoclonal antibody (mAb, clone FMC63. We describe a novel anti-idiotype monoclonal antibody (mAb to detect CD19-specific CAR(+ T cells before and after their adoptive transfer. This mouse mAb was generated by immunizing with a cellular vaccine expressing the antigen-recognition domain of FMC63. The specificity of the mAb (clone no. 136.20.1 was confined to the scFv region of the CAR as validated by inhibiting CAR-dependent lysis of CD19(+ tumor targets. This clone can be used to detect CD19-specific CAR(+ T cells in peripheral blood mononuclear cells at a sensitivity of 1∶1,000. In clinical settings the mAb is used to inform on the immunophenotype and persistence of administered CD19-specific T cells. Thus, our CD19-specific CAR mAb (clone no. 136.20.1 will be useful to investigators implementing CD19-specific CAR(+ T cells to treat B-lineage malignancies. The methodology described to develop a CAR-specific anti-idiotypic mAb could be extended to other gene therapy trials targeting different tumor associated antigens in the context of CAR-based adoptive T-cell therapy.

B cell-targeted therapy with anti-CD20 monoclonal antibody in a mouse model of Graves' hyperthyroidism.

Science.gov (United States)

Ueki, I; Abiru, N; Kobayashi, M; Nakahara, M; Ichikawa, T; Eguchi, K; Nagayama, Y

2011-03-01

Graves' disease is a B cell-mediated and T cell-dependent autoimmune disease of the thyroid which is characterized by overproduction of thyroid hormones and thyroid enlargement by agonistic anti-thyrotrophin receptor (TSHR) autoantibody. In addition to antibody secretion, B cells have recently been recognized to function as antigen-presenting/immune-modulatory cells. The present study was designed to evaluate the efficacy of B cell depletion by anti-mouse (m) CD20 monoclonal antibody (mAb) on Graves' hyperthyroidism in a mouse model involving repeated injection of adenovirus expressing TSHR A-subunit (Ad-TSHR289). We observe that a single injection of 250 µg/mouse anti-mCD20 mAb eliminated B cells efficiently from the periphery and spleen and to a lesser extent from the peritoneum for more than 3 weeks. B cell depletion before immunization suppressed an increase in serum immunoglobulin (Ig)G levels, TSHR-specific splenocyte secretion of interferon (IFN)-γ, anti-TSHR antibody production and development of hyperthyroidism. B cell depletion 2 weeks after the first immunization, a time-point at which T cells were primed but antibody production was not observed, was still effective at inhibiting antibody production and disease development without inhibiting splenocyte secretion of IFN-γ. By contrast, B cell depletion in hyperthyroid mice was therapeutically ineffective. Together, these data demonstrate that B cells are critical not only as antibody-producing cells but also as antigen-presenting/immune-modulatory cells in the early phase of the induction of experimental Graves' hyperthyroidism and, although therapeutically less effective, B cell depletion is highly efficient for preventing disease development. © 2011 The Authors. Clinical and Experimental Immunology © 2011 British Society for Immunology.

B cell-targeted therapy with anti-CD20 monoclonal antibody in a mouse model of Graves' hyperthyroidism

Science.gov (United States)

Ueki, I; Abiru, N; Kobayashi, M; Nakahara, M; Ichikawa, T; Eguchi, K; Nagayama, Y

2011-01-01

Graves' disease is a B cell-mediated and T cell-dependent autoimmune disease of the thyroid which is characterized by overproduction of thyroid hormones and thyroid enlargement by agonistic anti-thyrotrophin receptor (TSHR) autoantibody. In addition to antibody secretion, B cells have recently been recognized to function as antigen-presenting/immune-modulatory cells. The present study was designed to evaluate the efficacy of B cell depletion by anti-mouse (m) CD20 monoclonal antibody (mAb) on Graves' hyperthyroidism in a mouse model involving repeated injection of adenovirus expressing TSHR A-subunit (Ad-TSHR289). We observe that a single injection of 250 µg/mouse anti-mCD20 mAb eliminated B cells efficiently from the periphery and spleen and to a lesser extent from the peritoneum for more than 3 weeks. B cell depletion before immunization suppressed an increase in serum immunoglobulin (Ig)G levels, TSHR-specific splenocyte secretion of interferon (IFN)-γ, anti-TSHR antibody production and development of hyperthyroidism. B cell depletion 2 weeks after the first immunization, a time-point at which T cells were primed but antibody production was not observed, was still effective at inhibiting antibody production and disease development without inhibiting splenocyte secretion of IFN-γ. By contrast, B cell depletion in hyperthyroid mice was therapeutically ineffective. Together, these data demonstrate that B cells are critical not only as antibody-producing cells but also as antigen-presenting/immune-modulatory cells in the early phase of the induction of experimental Graves' hyperthyroidism and, although therapeutically less effective, B cell depletion is highly efficient for preventing disease development. PMID:21235532

Anti-Human Endoglin (hCD105 Immunotoxin—Containing Recombinant Single Chain Ribosome-Inactivating Protein Musarmin 1

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Begoña Barriuso

2016-06-01

Full Text Available Endoglin (CD105 is an accessory component of the TGF-β receptor complex, which is expressed in a number of tissues and over-expressed in the endothelial cells of tumor neovasculature. Targeting endoglin with immunotoxins containing type 2 ribosome-inactivating proteins has proved an effective tool to reduce blood supply to B16 mice tumor xenografts. We prepared anti-endoglin immunotoxin (IT—containing recombinant musarmin 1 (single chain ribosome-inactivating proteins linked to the mouse anti-human CD105 44G4 mouse monoclonal antibody via N-succinimidyl 3-(2-pyridyldithio propionate (SPDP. The immunotoxin specifically killed L929 fibroblast mouse cells transfected with the short form of human endoglin with IC50 values in the range of 5 × 10−10 to 10−9 M.

A phase I study of PRO131921, a novel anti-CD20 monoclonal antibody in patients with relapsed/refractory CD20+ indolent NHL: correlation between clinical responses and AUC pharmacokinetics.

Science.gov (United States)

Casulo, Carla; Vose, Julie M; Ho, William Y; Kahl, Brad; Brunvand, Mark; Goy, Andre; Kasamon, Yvette; Cheson, Bruce; Friedberg, Jonathan W

2014-09-01

PRO131921 is a third-generation, humanized anti-CD20 monoclonal antibody with increased antibody-dependent cytotoxicity and complement-dependent cytotoxicity compared to rituximab. In this phase I study, PRO131921 was administered as a single agent to patients with CD20+, relapsed or refractory, indolent non-Hodgkin lymphoma (NHL) who had been treated with a prior rituximab-containing regimen. The primary aim of this study was safety and tolerability of PRO131921. The secondary aim of the study, and focus of this report, was to determine the pharmacokinetics (PK) profile of PRO131921 and establish a correlation between drug exposure and clinical efficacy. Patients were treated with PRO131921 by intravenous infusion weekly for 4 weeks and the dose was escalated based on safety in a 3+3 design. Twenty-four patients were treated with PRO131921 at doses from 25mg/m(2) to 800 mg/m(2). Analysis of PK data demonstrated a correlation between higher normalized drug exposure (normalized AUC) and tumor shrinkage (p = .0035). Also, normalized AUC levels were higher among responders and subjects displaying tumor shrinkage versus subjects progressing or showing no regression (p = 0.030). In conclusion, PRO131921 demonstrated clinical activity in rituximab-relapsed and refractory indolent NHL patients. The observation that higher normalized AUC may be associated with improved clinical responses has potential implications in future trials of monoclonal antibody-based therapies, and emphasizes the importance of early PK studies to optimize antibody efficacy. Copyright © 2014 Elsevier Inc. All rights reserved.

Radiolabeling of anti-CD20 with Re0-188: liquid kit

Energy Technology Data Exchange (ETDEWEB)

Dias, Carla Roberta; Osso Junior, Joao Alberto [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: carlarobertab@yahoo.com.br; jaosso@ipen.br

2007-07-01

Radioimmunotherapy uses the targeting features of monoclonal antibody to deliver radiation from an attached radionuclide. The radionuclide {sup 188}Re is currently produced from the father nuclide {sup 188}W through a transportable generator system. Because of its easy availability and suitable nuclear properties (E{sub {beta}}{sub MAX} =2.1 MeV, t{sub 1/2}=16.9 h, E{sub {gamma}}=155 keV), this radionuclide is considered an attractive candidate for application as therapeutic agents and could be conveniently utilized for imaging and dosimetric purposes. The objective of this work is the optimization of radiolabeling of anti-CD20 with {sup 188}Re using a liquid formulation. Anti-CD20 was reduced by incubation with 2-ME and purified over a PD-10 column. The number of resulting free SH was assayed with Ellman's reagent. Optimization of radiolabeling was achieved by varying parameters: antibody mass, reducing agent, reaction time and {sup 188}Re volume in the liquid kit. Radiochemical purity of {sup 188}Re-anti-CD20 was evaluated. An average of 12 SH groups per mol in the reductions was found. The best labeling efficiency (> 93%) was achieved in the following conditions: 1 mg anti-CD20; 82.8 mg sodium tartrate; 1 mg SnCl{sub 2}; 0.25 mg gentisic acid, 1 mL {sup 188}Re and reaction time of 1 hour at room temperature. (author)

Efficacy and tolerability of gemtuzumab ozogamicin (anti-CD33 monoclonal antibody, CMA-676, Mylotarg® in children with relapsed/refractory myeloid leukemia

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Bertrand Yves

2006-06-01

Full Text Available Abstract Background Gemtuzumab ozogamicin (GO is a cytotoxic anti-CD33 monoclonal antibody that has given promising preliminary results in adult myeloid CD33+ AML. We conducted a retrospective multicenter study of 12 children treated with GO on a compassionate basis (median age 5.5 y. Three patients (2 MDS/AML, 1 JMML were refractory to first-line treatment, 8 patients with de novo AML were in refractory first relapse, and one patient with de novo AML was in 2nd relapse after stem cell transplantation (SCT. CD33 expression exceeded 20% in all cases. Methods GO was administered alone, at a unit dose of 3–9 mg/m2, once (3 patients, twice (3 patients, three (5 patients or five times (1 patient. Mean follow-up was 128 days (8–585 d. Results There were three complete responses (25% leading to further curative treatment (SCT. Treatment failed in the other nine patients, and only one patient was alive at the end of follow-up. NCI-CTC grade III/IV adverse events comprised hematological toxicity (n = 12, hypertransaminasemia (n = 2, allergy and hyperbilirubinemia (1 case each. There was only one major adverse event (grade IV allergy. No case of sinusoidal obstruction syndrome occurred. Conclusion These results warrant a prospective trial of GO in a larger population of children with AML.

Molecular mechanism for the action of the anti-CD44 monoclonal antibody MEM-85

Czech Academy of Sciences Publication Activity Database

Škerlová, Jana; Král, V.; Kachala, M.; Fábry, M.; Bumba, L.; Svergun, D. I.; Tošner, Z.; Veverka, Václav; Řezáčová, Pavlína

2015-01-01

Roč. 191, č. 2 (2015), s. 214-223 ISSN 1047-8477 R&D Projects: GA MŠk(CZ) LK11205; GA MŠk(CZ) LO1304 Institutional support: RVO:61388963 Keywords : CD44 * epitope mapping * monoclonal antibody * MEM-85 * NMR * SAXS Subject RIV: CE - Biochemistry Impact factor: 2.570, year: 2015

Prevention of diabetes: effect of mycophenolate mofetil and anti-CD25 on onset of diabetes in the DRBB rat.

Science.gov (United States)

Ugrasbul, Figen; Moore, Wayne V; Tong, Pei Ying; Kover, Karen L

2008-12-01

Anti-CD25 and mycophenolate mofetil (MMF) treatment of patients with new-onset diabetes is currently being tested as one of the trials in TrialNet. We tested the effectiveness of MMF and anti-CD25 in preventing autoimmune diabetes in the diabetes-resistant biobreeding (DRBB) rat. Autoimmune diabetes in the DRBB rat was induced with a Treg cell depletion regimen starting at 24-26 d of age. Treatment was started on the first day of the depletion regimen in the following groups: (i) control (vehicle); (ii) MMF 25 mg/kg/d intramuscularly daily for 8 wk; (iii) anti-CD25 0.8 mg/kg/d intraperitoneally 5 d/wk for 3 wk; and (iv) combination of MMF and anti-CD25. In a second set of experiments, treatments were started on day 5 of the depletion regimen (delayed treatment) with groups 1, 3, and 4. Rats that had diabetes-free survival for at least 30 d after the treatment was stopped underwent a second Treg depletion (redepletion). In each of the three treatment groups (n = 10/group), onset of diabetes was delayed or prevented in 20, 40 and 80% in groups 2, 3, and 4, respectively. After redepletion, diabetes-free survival was unchanged in group 2 and decreased to 10 and 30% in groups 3 and 4, respectively. With delayed treatment, groups 3 and 4 had 33 and 50% diabetes-free survival that decreased to 0 and 33% after redepletion. MMF and anti-CD25 alone or in combination are effective in delaying and preventing diabetes in the DRBB rat especially if treatment is started before stimulation and expansion of the autoreactive T cells.

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

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Haifeng Zhang

2013-09-01

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

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

International Nuclear Information System (INIS)

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

1987-01-01

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

Molecular mechanism for the action of the anti-CD44 monoclonal antibody MEM-85

Czech Academy of Sciences Publication Activity Database

Škerlová, Jana; Král, Vlastimil; Kachala, M.; Fábry, Milan; Bumba, Ladislav; Svergun, D.I.; Tosner, Z.; Veverka, V.; Řezáčová, Pavlína

2015-01-01

Roč. 191, č. 2 (2015), s. 214-223 ISSN 1047-8477 R&D Projects: GA ČR(CZ) GA15-11851S EU Projects: European Commission 264257 Institutional support: RVO:68378050 ; RVO:61388971 Keywords : CD44 * Epitope mapping * Monoclonal antibody * MEM-85 * SAXS * NMR Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.570, year: 2015

Método fosfatasa alcalina anti-fosfatasa alcalina para el diagnóstico de inmunodeficiencias celulares Alkaline phosphatase-anti-alkaline phosphatase method for the diagnosis of cell immunodeficiencies

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Berta B Socarrás Ferrer

2001-12-01

Full Text Available Para el estudio de 25 pacientes con infecciones recurrentes y un grupo control de 25 individuos supuestamente sanos, se aplicó, en nuestro laboratorio, el método inmunocitoquímico de fosfatasa alcalina anti-fosfatasa alcalina, para la cuantificación de las principales subpoblaciones de linfocitos T identificados con los anticuerpos monoclonales: anti-CD3, anti-CD4 y anti-CD8. Se obtuvieron diferencias significativas para las subpoblaciones TCD3 y CD4 positivos (p For the study of 25 patients with recurrent infections and a control group of 25 supposedly healthy individuals, our Laboratory applied the immunocytochemical method of alkaline phosphatase - anti-alkaline phosphatase for the quantitation of the main T-lymphocyte subgroups identified with monoclonal antibodies:antiCD3, anti-CD4 and anti-CD8. There were significant differences in positive TCD3 and CD4 subsets (p<0,05. Because this is a low cost and quick method, it may be applied by other immunodiagnosis labs throughout the country

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

Science.gov (United States)

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

2016-03-01

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

Generation of Affibody ligands binding interleukin-2 receptor alpha/CD25.

Science.gov (United States)

Grönwall, Caroline; Snelders, Eveline; Palm, Anna Jarelöv; Eriksson, Fredrik; Herne, Nina; Ståhl, Stefan

2008-06-01

Affibody molecules specific for human IL-2Ralpha, the IL-2 (interleukin-2) receptor alpha subunit, also known as CD25, were selected by phage-display technology from a combinatorial protein library based on the 58-residue Protein A-derived Z domain. The IL-2R system plays a major role in T-cell activation and the regulation of cellular immune responses. Moreover, CD25 has been found to be overexpressed in organ rejections, a number of autoimmune diseases and T-cell malignancies. The phage-display selection using Fc-fused target protein generated 16 unique Affibody molecules targeting CD25. The two most promising binders were characterized in more detail using biosensor analysis and demonstrated strong and selective binding to CD25. Kinetic biosensor analysis revealed that the two monomeric Affibody molecules bound to CD25 with apparent affinities of 130 and 240 nM respectively. The Affibody molecules were, on biosensor analysis, found to compete for the same binding site as the natural ligand IL-2 and the IL-2 blocking monoclonal antibody 2A3. Hence the Affibody molecules were assumed to have an overlapping binding site with IL-2 and antibodies targeting the IL-2 blocking Tac epitope (for example, the monoclonal antibodies Daclizumab and Basiliximab, both of which have been approved for therapeutic use). Furthermore, immunofluorescence microscopy and flow-cytometric analysis of CD25-expressing cells demonstrated that the selected Affibody molecules bound to CD4+ CD25+ PMBCs (peripheral-blood mononuclear cells), the IL-2-dependent cell line NK92 and phytohaemagglutinin-activated PMBCs. The potential use of the CD25-binding Affibody molecules as targeting agents for medical imaging and for therapeutic applications is discussed.

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

NARCIS (Netherlands)

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

1991-01-01

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

Anti-CD3 Antibody Ameliorates Transfusion-Associated Graft-Versus-Host Disease in a Chemotherapy-Based Mouse Model With Busulfan and Fludarabine

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Xiaofan Li

2017-05-01

Full Text Available ABSTRACT To establish a transfusion-associated graft-versus-host disease (TA-GVHD mouse model with busulfan and fludarabine for effective treatment evaluation. BALB/c (H-2d mice were injected with busulfan (15 mg/kg and fludarabine (30 mg/kg twice a day for 4 days. The mice were transfused with 106 T cell-depleted bone marrow (TCD-BM and cells in different groups 3 days after chemotherapy: syngeneic BALB/c, MHC minor mismatch DBA/2 (H-2d, or MHC major mismatch C57BL/6(H2-b. Recipient BALB/c mice were injected with either blood only or blood+splenocyte. TA-GVHD was monitored in terms of body weight loss, clinical scores, and survival. Dexamethasone (50 mg/kg, cyclophosphamide (50 mg/kg, cyclosporine A (30 mg/kg, and anti-CD3 (1 mg/kg were injected to each group to examine the treatments. Blood transfusion alone is insufficient to induce TA-GVHD in a chemotherapy-based mouse model. A MHC-mismatched TA-GVHD model can be induced by splenocyte and blood transfusion. This MHC-mismatched TA-GVHD model was resistant to dexamethasone treatment. Treatment based on anti-CD3 monoclonal antibody slightly ameliorated TA-GVHD. Treatment effectiveness was associated with T-cell depletion following activation by anti-CD3. Busulfan and fludarabine chemotherapy regimen can be used to establish a TA-GVHD mouse model. Anti-CD3 monoclonal antibody is a potential alternative to treat TA-GVHD.

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

International Nuclear Information System (INIS)

Morahan, G.

1983-01-01

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

Ofatumumab, a human anti-CD20 monoclonal antibody, for treatment of rheumatoid arthritis with an inadequate response to one or more disease-modifying antirheumatic drugs: results of a randomized, double-blind, placebo-controlled, phase I/II study

DEFF Research Database (Denmark)

Østergaard, Mikkel; Baslund, Bo; Rigby, William

2010-01-01

To investigate the safety and efficacy of ofatumumab, a novel human anti-CD20 monoclonal antibody (mAb), in patients with active rheumatoid arthritis (RA) whose disease did not respond to > or = 1 disease-modifying antirheumatic drug....

Biodistribution and pharmacokinetics of monoclonal antibody T1h and variant anti-CD6 murine 10D12 in healthy animals and in experimental arthritis model

International Nuclear Information System (INIS)

León, M; Hernández, I; Aldana, L; Ayra, F; Castro, Y; Leyva, R; García, L; Pérez, S.; Casaco, A.

2016-01-01

Biodistribution and pharmacokinetic of two radio labeled monoclonal antibodies was performed with the help of imaging techniques. Isotopic labeling was carried out by means of standardized methods. Pharmacokinetic evaluation was performed using the population approach and sparse data design. Introduction: Targeted therapy with monoclonal antibodies (MAb) is an efficient option for the treatment of rheumatoid arthritis. Th1 is a MAb anti human CD6 developed for the treatment of autoimmune disease and 10D12 is its counterpart anti murine CD6 developed as a pharmacological tool to get deep into the response mechanisms in animals models of rheumatoid arthritis.To investigate the behavior of both antibodies in the assay system, molecules were labeled with 125I to evaluate pharmacokinetic in healthy animals and with 99mTc to evaluate the antibody uptake in inflamed area of induced arthritis. Materials and methods: Antibodies were supplied by the Center of Molecular immunology. Iodination was performed by the iodogen method and technetium labeling was carried out directly by Schwarz method. Female C57BL6 from CENPALAB were used for experiments. Biodistribution and pharmacokinetic was performed by a sparse data design using the population approach. Uptake in region of inflammation was quantified by gammagraphy at the same time points of blood sampling. A compartmental model was build to quantify uptake kinetic. Pharmacokinetic profiles were analyzed using MONOLIX software version 4.2. Results: Minor pharmacokinetic differences were found between monoclonal antibodies labeled with 125I and 99mTc. As a humanized antibody, T1h shows a faster clearance than 10D12 and a biodistribution pattern reflecting preference for excretion mechanisms. The arthritis accumulation was not consistent with a targeted mediated uptake. On the other hand, radio labeled 10D12 shows an accumulation profile in arthritis with two peaks of maximum concentration representing an initial transit to

Ex vivo generation of human alloantigen-specific regulatory T cells from CD4(posCD25(high T cells for immunotherapy.

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Jorieke H Peters

Full Text Available BACKGROUND: Regulatory T cell (Treg based immunotherapy is a potential treatment for several immune disorders. By now, this approach proved successful in preclinical animal transplantation and auto-immunity models. In these models the success of Treg based immunotherapy crucially depends on the antigen-specificity of the infused Treg population. For the human setting, information is lacking on how to generate Treg with direct antigen-specificity ex vivo to be used for immunotherapy. METHODOLOGY/PRINCIPAL FINDINGS: Here, we demonstrate that in as little as two stimulation cycles with HLA mismatched allogeneic stimulator cells and T cell growth factors a very high degree of alloantigen-specificity was reached in magnetic bead isolated human CD4(posCD25(high Treg. Efficient increases in cell numbers were obtained. Primary allogeneic stimulation appeared a prerequisite in the generation of alloantigen-specific Treg, while secondary allogeneic or polyclonal stimulation with anti-CD3 plus anti-CD28 monoclonal antibodies enriched alloantigen-specificity and cell yield to a similar extent. CONCLUSIONS/SIGNIFICANCE: The ex vivo expansion protocol that we describe will very likely increase the success of clinical Treg-based immunotherapy, and will help to induce tolerance to selected antigens, while minimizing general immune suppression. This approach is of particular interest for recipients of HLA mismatched transplants.

Enhanced efficacy of gemcitabine in combination with anti-CD20 monoclonal antibody against CD20+ non-Hodgkin's lymphoma cell lines in vitro and in scid mice

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Jin Fang

2005-08-01

Full Text Available Abstract Background Despite exciting new targeted therapeutics against non-Hodgkin's lymphoma (NHL, chemotherapy remains a cornerstone of therapy. While purine nucleoside analogs have significant activity in low grade NHL, the pyrimidine nucleoside analog gemcitabine has been less extensively studied, but has important activity. Use of the anti-CD20 monoclonal antibody rituximab in combination with chemotherapy for B-NHL is becoming prevalent in clinical practice, but has not been extensively studied in pre-clinical models. Methods We have tested the activity of gemcitabine ± rituximab in vitro and in scid/human NHL xenograft models. We used two t(14;18+, CD20+ follicular B cell NHL cell lines, DoHH2 a transformed NHL line and WSU-FSCCL isolated from pleural fluid of a patient with indolent NHL. Results Gemcitabine is cytotoxic to DoHH2 and WSU-FSCCL cells in vitro, and the IC50 is 2–3 fold lower in the presence of rituximab. Apoptosis is also enhanced in the presence of rituximab. Clearance of NHL cells from ascites in scid mice is prolonged by the combination, as compared with either agent alone. Most importantly, survival of scid mice bearing human NHL cells is significantly prolonged by the combination of gemcitabine + rituximab. Conclusion Based on our pre-clinical data showing prolonged survival of mice bearing human lymphoma cell line xenografts after treatment with gemcitabine + anti-CD20 antibody, this combination, expected to have non-overlapping toxicity profiles, should be explored in clinical trials.

The challenge of treating hepatitis C virus-associated cryoglobulinemic vasculitis in the era of anti-CD20 monoclonal antibodies and direct antiviral agents.

Science.gov (United States)

Roccatello, Dario; Sciascia, Savino; Rossi, Daniela; Solfietti, Laura; Fenoglio, Roberta; Menegatti, Elisa; Baldovino, Simone

2017-06-20

Mixed cryoglobulinemia syndrome (MC) is a systemic vasculitis involving kidneys, joints, skin, and peripheral nerves. While many autoimmune, lymphoproliferative, and neoplastic disorders have been associated with this disorder, hepatitis C virus (HCV) is known to be the etiologic agent in the majority of patients. Therefore, clinical research has focused on anti-viral drugs and, more recently, on the new, highly potent Direct-acting Antiviral Agents (DAAs). These drugs assure sustained virologic response (SVR) rates >90%. Nevertheless, data on their efficacy in patients with HCV-associated cryoglobulinemic vasculitis are disappointing, possibly due to the inability of the drugs to suppress the immune-mediated process once it has been triggered.Despite the potential risk of exacerbation of the infection, immunosuppression has traditionally been regarded as the first-line intervention in cryoglobulinemic vasculitis, especially if renal involvement is severe. Biologic agents have raised hopes for more manageable therapeutic approaches, and Rituximab (RTX), an anti CD20 monoclonal antibody, is the most widely used biologic drug. It has proved to be safer than conventional immunosuppressants, thus substantially changing the natural history of HCV-associated cryoglobulinemic vasculitis by providing long-term remission, especially with intensive regimens.The present review focuses on the new therapeutic opportunities offered by the combination of biological drugs, mainly Rituximab, with DAAs.

In vitro characterization of 177Lu-radiolabelled chimeric anti-CD20 monoclonal antibody and a preliminary dosimetry study

International Nuclear Information System (INIS)

Forrer, Flavio; Mueller-Brand, Jan; Chen, Jianhua; Fani, Melpomeni; Powell, Pia; Maecke, Helmut R.; Lohri, Andreas; Moldenhauer, Gerhard

2009-01-01

131 I- and 90 Y-labelled anti-CD20 antibodies have been shown to be effective in the treatment of low-grade, B-cell non-Hodgkin's lymphoma (NHL). However, the most appropriate radionuclide in terms of high efficiency and low toxicity has not yet been established. In this study we evaluated an immunoconjugate formed by the anti-CD20 antibody rituximab and the chelator DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid). DOTA-rituximab was prepared as a kit formulation and can be labelled in a short time ( 177 Lu or 90 Y. Immunoconjugates with different numbers of DOTA molecules per rituximab were prepared using p-SCN-Bz-DOTA. In vitro immunoreactivity and stability were tested and preliminary dosimetric results were acquired in two patients. The immunological binding properties of DOTA-rituximab to the CD20 antigen were found to be retained after conjugation with up to four chelators. The labelled product was stable against a 10 5 times excess of diethylenetriaminepentaacetic acid (DTPA, 37 C, 7 days). Two patients with relapsed NHL were treated with 740 MBq/m 2 body surface 177 Lu-DOTA-rituximab. Scintigraphic images showed specific uptake at tumour sites and acceptable dosimetric results. The mean whole-body dose was found to be 314 mGy. The administration of 177 Lu-DOTA-rituximab was tolerated well. Our results show that DOTA-rituximab (4:1) can be labelled with 177 Lu with sufficient stability while the immunoconjugate retains its immunoreactivity. 177 Lu-DOTA-rituximab is an interesting, well-tolerated radiolabelled antibody with clinical activity in a low dose range, and provides an approach to the efficient treatment with few side effects for patients with relapsed NHL. (orig.)

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

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Qi Zhao

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

First clinical use of ofatumumab, a novel fully human anti-CD20 monoclonal antibody in relapsed or refractory follicular lymphoma

DEFF Research Database (Denmark)

Hagenbeek, Anton; Gadeberg, Ole Vestergaard; Johnson, Peter

2008-01-01

Ofatumumab is a unique monoclonal antibody that targets a distinct small loop epitope on the CD20 molecule. Preclinical data show that ofatumumab is active against B-cell lymphoma/chronic lymphocytic leukemia cells with low CD20-antigen density and high expression of complement inhibitory molecules...

Antigenic modulation limits the effector cell mechanisms employed by type I anti-CD20 monoclonal antibodies.

Science.gov (United States)

Tipton, Thomas R W; Roghanian, Ali; Oldham, Robert J; Carter, Matthew J; Cox, Kerry L; Mockridge, C Ian; French, Ruth R; Dahal, Lekh N; Duriez, Patrick J; Hargreaves, Philip G; Cragg, Mark S; Beers, Stephen A

2015-03-19

Following the success of rituximab, 2 other anti-CD20 monoclonal antibodies (mAbs), ofatumumab and obinutuzumab, have entered clinical use. Ofatumumab has enhanced capacity for complement-dependent cytotoxicity, whereas obinutuzumab, a type II mAb, lacks the ability to redistribute into lipid rafts and is glycoengineered for augmented antibody-dependent cellular cytotoxicity (ADCC). We previously showed that type I mAbs such as rituximab have a propensity to undergo enhanced antigenic modulation compared with type II. Here we assessed the key effector mechanisms affected, comparing type I and II antibodies of various isotypes in ADCC and antibody-dependent cellular-phagocytosis (ADCP) assays. Rituximab and ofatumumab depleted both normal and leukemic human CD20-expressing B cells in the mouse less effectively than glycoengineered and wild-type forms of obinutuzumab, particularly when human immunoglobulin G1 (hIgG1) mAbs were compared. In contrast to mouse IgG2a, hIgG1 mAbs were ineffective in ADCC assays with murine natural killer cells as effectors, whereas ADCP was equivalent for mouse IgG2a and hIgG1. However, rituximab's ability to elicit both ADCC and ADCP was reduced by antigenic modulation, whereas type II antibodies remained unaffected. These data demonstrate that ADCP and ADCC are impaired by antigenic modulation and that ADCP is the main effector function employed in vivo. © 2015 by The American Society of Hematology.

Preparation of anti-CD4 monoclonal antibody-conjugated magnetic poly(glycidyl methacrylate) particles and their application on CD4+ lymphocyte separation.

Science.gov (United States)

Pimpha, Nuttaporn; Chaleawlert-umpon, Saowaluk; Chruewkamlow, Nuttapol; Kasinrerk, Watchara

2011-03-15

Novel immunomagnetic particles have been prepared for separation of CD4(+) lymphocytes. The magnetic nanoparticles with a diameter of approximately 5-6 nm were first synthesized by co-precipitation from ferrous and ferric iron solutions and subsequently encapsulated with poly(glycidyl methacrylate) (PGMA) by precipitation polymerization. Monoclonal antibody specific to CD4 molecules expressed on CD4(+) lymphocytes was conjugated to the surface of magnetic PGMA particles through covalent bonding between epoxide functional groups on the particle surface and primary amine groups of the antibodies. The generated immunomagnetic particles have successfully separated CD4(+) lymphocytes from whole blood with over 95% purity. The results indicated that these particles can be employed for cell separation and provide a strong potential to be applied in various biomedical applications including diagnosis, and monitoring of human diseases. Copyright © 2010 Elsevier B.V. All rights reserved.

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

Science.gov (United States)

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

2017-01-01

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

Influence of radiotherapy on CD4+ CD25high regulatory cells in peripheral blood of NPC patients

International Nuclear Information System (INIS)

Liu Li; Ding Qian; Song Yingqiu; Cao Rubo; Yao Junxia; Huang Shiang

2006-01-01

Objective: The current study was designed to investigate the changes in peripheral CD4 + CD25 high regulatory T (CD4 + CD25 high Tr) cells in patients with nasopharyngeal carcinoma (NPC) and the influence of radiotherapy on immunity function. Methods: The peripheral blood was collected from 36 patients with NPC and 30 healthy controls. By using monoclonal antibodies, the blood samples were evaluated with flow cytometry for lymphocyte subsets and Tr cells. Results: The ratio of CD4 + /CD8 + in the NPC group was not significantly less than that in the healthy controls (P>0.05), but the prevalence of the CD4 + CD25 high Tr cells was significantly higher than that of the healthy group [(2.76 ± 1.06)% versus (2.06 ± 0.98)%, P + CD25 high Tr cells was higher than before it [(4.88 ± 1.02)%, P + CD25 high Tr cells in peripheral blood of NPC patients with or without radiotherapy was significantly higher than those in healthy controls, which may be related to immunosupression and tumor progression in such patients. This finding suggests that CD4 + CD25 high Tr cells in peripheral blood of NPC patients can be a useful index for monitoring the immunity function. (authors)

Cyclosporine inhibits long-term survival in cardiac allografts treated with monoclonal antibody against CD45RB

NARCIS (Netherlands)

Parry, N; Lazarovits, AI; Wang, JJ; Garcia, B; Luke, P; Poppema, S; Zhong, R

Background: We have previously reported that a monoclonal antibody to CD45RB is a novel immunosuppressive agent; however, the optimal regimen in cardiac allografts remains unknown. The present study was undertaken to determine the optimal protocol of this therapy and its interaction with

In vitro characterization of {sup 177}Lu-radiolabelled chimeric anti-CD20 monoclonal antibody and a preliminary dosimetry study

Energy Technology Data Exchange (ETDEWEB)

Forrer, Flavio; Mueller-Brand, Jan [University Hospital Basel, Institute of Nuclear Medicine, Basel (Switzerland); Chen, Jianhua; Fani, Melpomeni; Powell, Pia; Maecke, Helmut R. [University Hospital Basel, Division of Radiological Chemistry, Basel (Switzerland); Lohri, Andreas [Basel University Medical Clinic, Liestal (Switzerland); Moldenhauer, Gerhard [German Cancer Research Center, Division of Molecular Immunology, Heidelberg (Germany)

2009-09-15

{sup 131}I- and {sup 90}Y-labelled anti-CD20 antibodies have been shown to be effective in the treatment of low-grade, B-cell non-Hodgkin's lymphoma (NHL). However, the most appropriate radionuclide in terms of high efficiency and low toxicity has not yet been established. In this study we evaluated an immunoconjugate formed by the anti-CD20 antibody rituximab and the chelator DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid). DOTA-rituximab was prepared as a kit formulation and can be labelled in a short time (<20 min) with either {sup 177}Lu or {sup 90}Y. Immunoconjugates with different numbers of DOTA molecules per rituximab were prepared using p-SCN-Bz-DOTA. In vitro immunoreactivity and stability were tested and preliminary dosimetric results were acquired in two patients. The immunological binding properties of DOTA-rituximab to the CD20 antigen were found to be retained after conjugation with up to four chelators. The labelled product was stable against a 10{sup 5} times excess of diethylenetriaminepentaacetic acid (DTPA, 37 C, 7 days). Two patients with relapsed NHL were treated with 740 MBq/m{sup 2} body surface {sup 177}Lu-DOTA-rituximab. Scintigraphic images showed specific uptake at tumour sites and acceptable dosimetric results. The mean whole-body dose was found to be 314 mGy. The administration of {sup 177}Lu-DOTA-rituximab was tolerated well. Our results show that DOTA-rituximab (4:1) can be labelled with {sup 177}Lu with sufficient stability while the immunoconjugate retains its immunoreactivity. {sup 177}Lu-DOTA-rituximab is an interesting, well-tolerated radiolabelled antibody with clinical activity in a low dose range, and provides an approach to the efficient treatment with few side effects for patients with relapsed NHL. (orig.)

Development of a lyophilized formulation for preparing the radiopharmaceutical {sup 177}Lu-DOTA-Anti-CD20; Desarrollo de una formulacion liofilizada para la preparacion del radiofarmaco {sup 177}-DOTA-Anti-CD20

Energy Technology Data Exchange (ETDEWEB)

Serrano E, L. A.

2015-07-01

The radiolabeled proteins are molecules of interest in nuclear medicine for their diagnostic and therapeutic application in cancer. Antibodies, such as chimeric monoclonal antibody Anti-CD20 rituximab, have established themselves as suitable vectors of radionuclides (e.g. {sup 177}Lu) , introducing high affinity by the surface antigens over- expressed and widely distributed in cells involved in certain diseases. The aim of this work was to design, optimize and document the production process of radiopharmaceutical {sup 177}Lu-DOTA-Anti-CD20 for sanitary registration request to the Comision Federal para la Proteccion contra Riesgos Sanitarios (COFEPRIS). First, a raw material analysis using the Ft-Mir technique and gamma spectrometry was performed. Then, was carried out the development of the lyophilized formulation for the preparation of {sup 177}Lu-DOTA-Anti-CD20, in which an ANOVA was performed where the dependent variable was the radiochemical purity. The optimal pharmaceutical formulation was: 5 mg DOTA-CD20 and 80 mg Mannitol to be reconstituted with 1 m L of acetate buffer 0.25 M, ph 7, with an incubation time of 15 min at 37 degrees Celsius in a dry bath. Once completed the development of the lyophilized formulation, we proceeded to the optimization of the production process, development and validation of the analytical method. Three batches were prepared under protocols of Good Manufacturing Practice, which met pre-established specifications as sterile and endotoxin-free of bacterial formulations, with greater that 95% of radiochemical purity. Currently, is conducting the study of shelf stability. Upon completion of the stability studies, the legal record of {sup 177}Lu-DOTA-Anti-CD20 will be integrated with documented evidence of the quality and stability of the formulation of this radiopharmaceutical. (Author)

Increased T cell proliferative responses to islet antigens identify clinical responders to anti-CD20 monoclonal antibody (rituximab) therapy in type 1 diabetes.

Science.gov (United States)

Herold, Kevan C; Pescovitz, Mark D; McGee, Paula; Krause-Steinrauf, Heidi; Spain, Lisa M; Bourcier, Kasia; Asare, Adam; Liu, Zhugong; Lachin, John M; Dosch, H Michael

2011-08-15

Type 1 diabetes mellitus is believed to be due to the autoimmune destruction of β-cells by T lymphocytes, but a single course of rituximab, a monoclonal anti-CD20 B lymphocyte Ab, can attenuate C-peptide loss over the first year of disease. The effects of B cell depletion on disease-associated T cell responses have not been studied. We compare changes in lymphocyte subsets, T cell proliferative responses to disease-associated target Ags, and C-peptide levels of participants who did (responders) or did not (nonresponders) show signs of β-cell preservation 1 y after rituximab therapy in a placebo-controlled TrialNet trial. Rituximab decreased B lymphocyte levels after four weekly doses of mAb. T cell proliferative responses to diabetes-associated Ags were present at baseline in 75% of anti-CD20- and 82% of placebo-treated subjects and were not different over time. However, in rituximab-treated subjects with significant C-peptide preservation at 6 mo (58%), the proliferative responses to diabetes-associated total (p = 0.032), islet-specific (p = 0.048), and neuronal autoantigens (p = 0.005) increased over the 12-mo observation period. This relationship was not seen in placebo-treated patients. We conclude that in patients with type 1 diabetes mellitus, anti-B cell mAb causes increased proliferative responses to diabetes Ags and attenuated β-cell loss. The way in which these responses affect the disease course remains unknown.

Synergy of anti-CD40, CpG and MPL in activation of mouse macrophages.

Science.gov (United States)

Shi, Yongyu; Felder, Mildred A R; Sondel, Paul M; Rakhmilevich, Alexander L

2015-08-01

Activation of macrophages is a prerequisite for their antitumor effects. Several reagents, including agonistic anti-CD40 monoclonal antibody (anti-CD40), CpG oligodeoxynucleotides (CpG) and monophosphoryl lipid A (MPL), can stimulate activation of macrophages. Our previous studies showed synergy between anti-CD40 and CpG and between anti-CD40 and MPL in macrophage activation and antitumor efficacy in mice. In the present study, we asked whether there was synergy among these three reagents. The activation of adherent peritoneal exudate cells (PEC) obtained from mice injected with anti-CD40 and then treated with CpG and/or MPL in vitro was determined by their ability to suppress proliferation of tumor cells and to produce various cytokines and chemokines in vitro. Cell sorting and histology followed by functional testing showed that macrophages were the main cell population in PEC activated by CD40 ligation in vivo. A combination of anti-CD40, CpG or MPL activated PEC to suppress proliferation of B16 cells and produce nitric oxide far greater than the single reagents or any of the double combinations of these reagents. In addition, the combination of all three reagents activated PEC to secrete IL-12, IFN-γ and MCP-1 to a greater degree than any single reagent or any two combined reagents. These results demonstrate that macrophages can be synergistically activated by anti-CD40, CpG and MPL, suggesting that this novel combined approach might be further investigated as potential cancer therapy. Copyright © 2015 Elsevier Ltd. All rights reserved.

Synergy of anti-CD40, CpG and MPL in activation of mouse macrophages

Science.gov (United States)

Shi, Yongyu; Felder, Mildred A.R.; Sondel, Paul M.; Rakhmilevich, Alexander L.

2015-01-01

Activation of macrophages is a prerequisite for their antitumor effects. Several reagents, including agonistic anti-CD40 monoclonal antibody (anti-CD40), CpG oligodeoxynucleotides (CpG) and monophosphoryl lipid A (MPL), can stimulate activation of macrophages. Our previous studies showed synergy between anti-CD40 and CpG and between anti-CD40 and MPL in macrophage activation and antitumor efficacy in mice. In the present study, we asked whether there was synergy among these three reagents. The activation of adherent peritoneal exudate cells (PEC) obtained from mice injected with anti-CD40 and then treated with CpG and/or MPL in vitro was determined by their ability to suppress proliferation of tumor cells and to produce various cytokines and chemokines in vitro. Cell sorting and histology followed by functional testing showed that macrophages were the main cell population in PEC activated by CD40 ligation in vivo. A combination of anti-CD40, CpG or MPL activated PEC to suppress proliferation of B16 cells and produce nitric oxide far greater than the single reagents or any of the double combinations of these reagents. In addition, the combination of all three reagents activated PEC to secrete IL-12, IFN-γ and MCP-1 to a greater degree than any single reagent or any two combined reagents. These results demonstrate that macrophages can be synergistically activated by anti-CD40, CpG and MPL, suggesting that this novel combined approach might be further investigated as potential cancer therapy. PMID:25829245

Enhancement of retroviral infection in vitro by anti-Le(y) IgG: reversal by humanization of monoclonal mouse antibody

DEFF Research Database (Denmark)

Hansen, J E; Sørensen, A M; Arendrup, M

1993-01-01

Monoclonal mouse IgG3 antibody (ABL 364) against the carbohydrate Le(y) antigen enhanced infection in vitro with HTLV-1 and with HIV-1 when propagated in both transformed and normal lymphocytes. Enhancement was independent of complement, occurred with both lymphocytes and monocytes as target cells...... with no indication of any alternative pathway of infection, as evidenced by abrogation of enhancement by anti-CD4 MAb or soluble recombinant CD4, and also the inability of anti-Le(y) MAb to mediate HIV infection of HSB-2 cells in which HTLV-1/HIV pseudovirus infection was enhanced. While F(ab)2 fragments of ABL 364...

Protective Effect of CXCR3+CD4+CD25+Foxp3+ Regulatory T Cells in Renal Ischemia-Reperfusion Injury

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Cao Jun

2015-01-01

Full Text Available Regulatory T cells (Tregs suppress excessive immune responses and are potential therapeutic targets in autoimmune disease and organ transplantation rejection. However, their role in renal ischemia-reperfusion injury (IRI is unclear. Levels of Tregs and expression of CXCR3 in Tregs were analyzed to investigate their function in the early phase of renal IRI. Mice were randomly divided into Sham, IRI, and anti-CD25 (PC61 + IRI groups. The PC61 + IRI group was established by i.p. injection of PC61 monoclonal antibody (mAb to deplete Tregs before renal ischemia. CD4+CD25+Foxp3+ Tregs and CXCR3 on Tregs were analyzed by flow cytometry. Blood urea nitrogen (BUN, serum creatinine (Scr levels, and tubular necrosis scores, all measures of kidney injury, were greater in the IRI group than in the Sham group. Numbers of Tregs were increased at 72 h after reperfusion in kidney. PC61 mAb preconditioning decreased the numbers of Tregs and aggravated kidney injury. There was no expression of CXCR3 on Tregs in normal kidney, while it expanded at 72 h after reperfusion and inversely correlated with BUN, Scr, and kidney histology score. This indicated that recruitment of Tregs into the kidney was related to the recovery of renal function after IRI and CXCR3 might be involved in the migration of Tregs.

Apoptosis Signaling Is Altered in CD4⁺CD25⁺FoxP3⁺ T Regulatory Lymphocytes in Pre-Eclampsia

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Jan Oleszczuk

2012-05-01

Full Text Available The aim of our study was to estimate the surface expressions of CD95 (APO-1/Fas antigen and the intracellular expressions of anti-apoptotic protein Bcl-2 and pro-apoptotic protein Bax in CD4⁺CD25⁺FoxP3⁺ T regulatory lymphocytes (Tregs as well as the percentage of CD8⁺CD28⁺ T cytotoxic cells in peripheral blood of patients with pre-eclampsia in comparison with healthy pregnant women in the third trimester of physiological pregnancy. Twenty-four women with pre-eclampsia and 20 normal third trimester pregnant women were included in the study. The lymphocytes were isolated from peripheral blood samples and labeled with monoclonal antibodies. The expressions of surface antigens and intracellular proteins were estimated using flow cytometry. The population of CD4⁺CD25⁺FoxP3⁺ Treg cells was significantly lower in peripheral blood of patients with pre-eclampsia when compared to normal third trimester pregnant women. The percentages of CD4⁺CD25⁺FoxP3⁺ Treg cells that express Bcl-2 protein were significantly lower in peripheral blood of patients with pre-eclampsia when compared to healthy pregnant women, whereas the percentages of CD4⁺CD25⁺FoxP3⁺ Treg cells with the expressions of Bax protein did not differ in both groups. Moreover, the mean fluorescence intensity (MFI of Bcl-2 protein in CD4⁺CD25⁺FoxP3⁺ Treg cells was significantly lower and MFI of Bax protein significantly higher in pre-eclampsia when compared to the control group. The percentage of CD8⁺CD28⁺ T cells did not differ in both studied groups but MFI of CD28 antigen on T CD8⁺ cells was significantly higher in pre-eclampsia when compared to the control group. The obtained results suggest that the deficit of CD4⁺CD25⁺FoxP3⁺ Treg

Co-stimulation by anti-immunoglobulin is required for B cell activation by CD40Llow T cells

DEFF Research Database (Denmark)

Poudrier, J; Owens, T

1994-01-01

cell Ag specificity by using anti-CD3/T cell receptor (TcR) monoclonal antibodies (mAb) to activate T cells. To study the role of sIg engagement in the responsiveness of B cells to T help, we pre-treated small resting B cells with soluble anti-kappa mAb prior to contact with an activated Th1 clone...... strongly. Low buoyant density B cells also responded to CD40Llow Th cells. There was no B cell response to resting Th cells. mAb against CD54/intercellular adhesion molecule-1 or major histocompatibility complex (MHC) class II completely inhibited B cell responses to CD40Llow Th1 cells, equivalent...

Development of a lyophilized formulation for preparing the radiopharmaceutical 177Lu-DOTA-Anti-CD20

International Nuclear Information System (INIS)

Serrano E, L. A.

2015-01-01

The radiolabeled proteins are molecules of interest in nuclear medicine for their diagnostic and therapeutic application in cancer. Antibodies, such as chimeric monoclonal antibody Anti-CD20 rituximab, have established themselves as suitable vectors of radionuclides (e.g. 177 Lu) , introducing high affinity by the surface antigens over- expressed and widely distributed in cells involved in certain diseases. The aim of this work was to design, optimize and document the production process of radiopharmaceutical 177 Lu-DOTA-Anti-CD20 for sanitary registration request to the Comision Federal para la Proteccion contra Riesgos Sanitarios (COFEPRIS). First, a raw material analysis using the Ft-Mir technique and gamma spectrometry was performed. Then, was carried out the development of the lyophilized formulation for the preparation of 177 Lu-DOTA-Anti-CD20, in which an ANOVA was performed where the dependent variable was the radiochemical purity. The optimal pharmaceutical formulation was: 5 mg DOTA-CD20 and 80 mg Mannitol to be reconstituted with 1 m L of acetate buffer 0.25 M, ph 7, with an incubation time of 15 min at 37 degrees Celsius in a dry bath. Once completed the development of the lyophilized formulation, we proceeded to the optimization of the production process, development and validation of the analytical method. Three batches were prepared under protocols of Good Manufacturing Practice, which met pre-established specifications as sterile and endotoxin-free of bacterial formulations, with greater that 95% of radiochemical purity. Currently, is conducting the study of shelf stability. Upon completion of the stability studies, the legal record of 177 Lu-DOTA-Anti-CD20 will be integrated with documented evidence of the quality and stability of the formulation of this radiopharmaceutical. (Author)

Modulation of Cytokine Production by Drugs with Antiepileptic or Mood Stabilizer Properties in Anti-CD3- and Anti-CD40-Stimulated Blood In Vitro

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Hubertus Himmerich

2014-01-01

Full Text Available Increased cytokine production possibly due to oxidative stress has repeatedly been shown to play a pivotal role in the pathophysiology of epilepsy and bipolar disorder. Recent in vitro and animal studies of valproic acid (VPA report antioxidative and anti-inflammatory properties, and suppression of interleukin (IL-6 and tumor necrosis factor (TNF-α. We tested the effect of drugs with antiepileptic or mood stabilizer properties, namely, primidone (PRM, carbamazepine (CBZ, levetiracetam (LEV, lamotrigine (LTG, VPA, oxcarbazepine (OXC, topiramate (TPM, phenobarbital (PB, and lithium on the production of the following cytokines in vitro: interleukin (IL-1β, IL-2, IL-4, IL-6, IL-17, IL-22, and TNF-α. We performed a whole blood assay with stimulated blood of 14 healthy female subjects. Anti-human CD3 monoclonal antibody OKT3, combined with 5C3 antibody against CD40, was used as stimulant. We found a significant reduction of IL-1 and IL-2 levels with all tested drugs other than lithium in the CD3/5C3-stimulated blood; VPA led to a decrease in IL-1β, IL-2, IL-4, IL-6, IL-17, and TNF-α production, which substantiates and adds knowledge to current hypotheses on VPA’s anti-inflammatory properties.

Radiolabeling and Preclinical Evaluation of 131I-anti-CD20 for Non-Hodgkin's Lymphomas Therapy

International Nuclear Information System (INIS)

Kullaprawittaya, Usa; Khongpetch, Pranom; Ngamprayad, Tippanan; Nuanchuen, Suphatphong

2007-08-01

Full text: In this study, a monoclonal anti-CD20 was developed for radioimmunotherapy of non-Hodgkin's B-cell lymphoma by reacting anti-CD20 with iodine-131 using iodogen procedure. It was found that radiochemical yield was > 95 % independently of incubation time and the antibody could be conjugated with iodine-131 up to 10 mCi/mg. The radiolabeled antibody exhibited excellent retention of immunoreactivity with radio incorporations >95% for 6 hr at 4 o C. In vitro stability tests showed minimal loss of iodine-131 from the conjugate in the presence of cysteine and in human serum at 37 o C. Biodistribution study in normal ICR mice showed higher uptake by the liver, kidney and intestines but lower thyroid uptake compared to 131 I -MIBG. Biodistribution studies confirmed the in vitro stability of 131 I -anti-CD20. In particular, excellent in vivo retention of iodine-131 was demonstrated by lower thyroid accumulation over 48 hr. A favorable biological distribution of 131 I -anti-CD20 suggests this radiopharmaceutical may be effectively used in the therapy of non-Hodgkin's lymphoma

Evaluation of monoclonal anti-A and anti-B and affinity-purified Ulex europaeus lectin I for forensic blood grouping.

Science.gov (United States)

Gaensslen, R E; Lee, H C; Carroll, J E

1984-01-01

Two different monoclonal anti-A and anti-B and several different affinity purified Ulex europaeus lectin I reagents were evaluated and compared with conventional anti-A and anti-B sera and Ulex anti-H for serologic properties, in inhibition tests with secretor salivas, and in elution tests with bloodstains. The monoclonal and purified reagents were found to be comparable to conventional ones, and accordingly suitable for forensic inhibition and elution procedures.

Monoclonal antibody 1.6.1 against human MPL receptor allows HSC enrichment of CB and BM CD34(+)CD38(-) populations.

Science.gov (United States)

Petit Cocault, Laurence; Fleury, Maud; Clay, Denis; Larghero, Jérôme; Vanneaux, Valérie; Souyri, Michèle

2016-04-01

Thrombopoietin (TPO) and its receptor Mpl (CD110) play a crucial role in the regulation of hematopoietic stem cells (HSCs). Functional study of Mpl-expressing HSCs has, however, been hampered by the lack of efficient monoclonal antibodies, explaining the very few data available on Mpl(+) HSCs during human embryonic development and after birth. Investigating the main monoclonal antibodies used so far to sort CD110(+) cells from cord blood (CB) and adult bone marrow (BM), we found that only the recent monoclonal antibody 1.6.1 engineered by Immunex Corporation was specific. Using in vitro functional assays, we found that this antibody can be used to sort a CD34(+)CD38(-)CD110(+) population enriched in hematopoietic progenitor stem cells, both in CB and in adult BM. In vivo injection into NSG mice further indicated that the CB CD34(+)CD38(-)CD110(+) population is highly enriched in HSCs compared with both CD34(+)CD38(-)CD110(-) and CD34(+)CD38(-) populations. Together our results validate MAb1.6.1 as an important tool, which has so far been lacking, in the HSC field. Copyright © 2016 ISEH - International Society for Experimental Hematology. Published by Elsevier Inc. All rights reserved.

Interactions between ibrutinib and anti-CD20 antibodies; competing effects on the outcome of combination therapy

Science.gov (United States)

Skarzynski, Martin; Niemann, Carsten U; Lee, Yuh Shan; Martyr, Sabrina; Maric, Irina; Salem, Dalia; Stetler-Stevenson, Maryalice; Marti, Gerald E; Calvo, Katherine R; Yuan, Constance; Valdez, Janet; Soto, Susan; Farooqui, Mohammed Z.H.; Herman, Sarah E.M.; Wiestner, Adrian

2015-01-01

Purpose Clinical trials of ibrutinib combined with anti-CD20 monoclonal antibodies (mAbs) for chronic lymphocytic leukemia (CLL) report encouraging results. Paradoxically, in pre-clinical studies in vitro ibrutinib was reported to decrease CD20 expression and inhibits cellular effector mechanisms. We therefore set out to investigate effects of in vivo ibrutinib treatment that could explain this paradox. Experimental Design Patients received single agent ibrutinib (420mg daily) on an investigator-initiated phase 2 trial. Serial blood samples were collected pre-treatment and during treatment for ex vivo functional assays to examine the effects on CLL cell susceptibility to anti-CD20 mAbs. Results We demonstrate that CD20 expression on ibrutinib was rapidly and persistently down-regulated (median reduction 74%, day 28, Pibrutinib were less susceptible to anti-CD20 mAb-mediated complement-dependent cytotoxicity than pre-treatment cells (median reduction 75%, Pibrutinib, providing a likely mechanism for the preserved C3d opsonization. Additionally, ibrutinib significantly inhibited trogocytosis, a major contributor to antigen loss and tumor escape during mAb therapy. Conclusions Our data indicate that ibrutinib promotes both positive and negative interactions with anti-CD20 mAbs, suggesting that successfully harnessing maximal anti-tumor effects of such combinations requires further investigation. PMID:26283682

Evaluation of (89Zr-labeled human anti-CD147 monoclonal antibody as a positron emission tomography probe in a mouse model of pancreatic cancer.

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Aya Sugyo

Full Text Available INTRODUCTION: Pancreatic cancer is an aggressive cancer and its prognosis remains poor. Therefore, additional effective therapy is required to augment and/or complement current therapy. CD147, high expression in pancreatic cancer, is involved in the metastatic process and is considered a good candidate for targeted therapy. CD147-specfic imaging could be useful for selection of appropriate patients. Therefore, we evaluated the potential of a fully human anti-CD147 monoclonal antibody 059-053 as a new positron emission tomography (PET probe for pancreatic cancer. METHODS: CD147 expression was evaluated in four pancreatic cancer cell lines (MIA Paca-2, PANC-1, BxPC-3, and AsPC-1 and a mouse cell line A4 as a negative control. Cell binding, competitive inhibition and internalization assays were conducted with (125I-, (67Ga-, or (89Zr-labeled 059-053. In vivo biodistribution of (125I- or (89Zr-labeled 059-053 was conducted in mice bearing MIA Paca-2 and A4 tumors. PET imaging with [(89Zr]059-053 was conducted in subcutaneous and orthotopic tumor mouse models. RESULTS: Among four pancreatic cancer cell lines, MIA Paca-2 cells showed the highest expression of CD147, while A4 cells had no expression. Immunohistochemical staining showed that MIA Paca-2 xenografts also highly expressed CD147 in vivo. Radiolabeled 059-053 specifically bound to MIA Paca-2 cells with high affinity, but not to A4. [(89Zr]059-053 uptake in MIA Paca-2 tumors increased with time from 11.0±1.3% injected dose per gram (ID/g at day 1 to 16.9±3.2% ID/g at day 6, while [(125I]059-053 uptake was relatively low and decreased with time, suggesting that 059-053 was internalized into tumor cells in vivo and (125I was released from the cells. PET with [(89Zr]059-053 clearly visualized subcutaneous and orthotopic tumors. CONCLUSION: [(89Zr]059-053 is a promising PET probe for imaging CD147 expression in pancreatic cancer and has the potential to select appropriate patients with CD147

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

International Nuclear Information System (INIS)

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

1988-01-01

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

Comparison of anti-CD3 and anti-CD28-coated beads with soluble anti-CD3 for expanding human T cells: Differing impact on CD8 T cell phenotype and responsiveness to restimulation

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Kurlander Roger J

2010-10-01

Full Text Available Abstract Background The ability to expand virus- or tumor-specific T cells without damaging their functional capabilities is critical for success adoptive transfer immunotherapy of patients with opportunistic infection or tumor. Careful comparisons can help identify expansion methods better suited for particular clinical settings and identify recurrent deficiencies requiring new innovation. Methods We compared the efficacy of magnetic beads coated with anti-CD3 and anti-CD28 (anti-CD3/CD28 beads, and soluble anti-CD3 plus mixed mononuclear cells (designated a rapid expansion protocol or REP in expanding normal human T cells. Results Both anti-CD3/CD28 beads and soluble anti-CD3 promoted extensive expansion. Beads stimulated greater CD4 cell growth (geometric mean of 56- versus 27-fold (p Conclusions Anti-CD3/CD28 beads are highly effective for expanding CD4 cells, but soluble anti-CD3 has significant potential advantages for expanding CD8 T cells, particularly where preservation of phenotypically "young" CD8 cells would be desirable, or where the T cells of interest have been antigen-stimulated in vitro or in vivo in the recent past.

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

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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.

Isolation of highly suppressive CD25+FoxP3+ T regulatory cells from G-CSF-mobilized donors with retention of cytotoxic anti-viral CTLs: application for multi-functional immunotherapy post stem cell transplantation.

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Edward R Samuel

Full Text Available Previous studies have demonstrated the effective control of cytomegalovirus (CMV infections post haematopoietic stem cell transplant through the adoptive transfer of donor derived CMV-specific T cells (CMV-T. Strategies for manufacturing CMV immunotherapies has involved a second leukapheresis or blood draw from the donor, which in the unrelated donor setting is not always possible. We have investigated the feasibility of using an aliquot of the original G-CSF-mobilized graft as a starting material for manufacture of CMV-T and examined the activation marker CD25 as a targeted approach for identification and isolation following CMVpp65 peptide stimulation. CD25+ cells isolated from G-CSF-mobilized apheresis revealed a significant increase in the proportion of FoxP3 expression when compared with conventional non-mobilized CD25+ cells and showed a superior suppressive capacity in a T cell proliferation assay, demonstrating the emergence of a population of Tregs not present in non-mobilized apheresis collections. The expansion of CD25+ CMV-T in short-term culture resulted in a mixed population of CD4+ and CD8+ T cells with CMV-specificity that secreted cytotoxic effector molecules and lysed CMVpp65 peptide-loaded phytohaemagglutinin-stimulated blasts. Furthermore CD25 expanded cells retained their suppressive capacity but did not maintain FoxP3 expression or secrete IL-10. In summary our data indicates that CD25 enrichment post CMV stimulation in G-CSF-mobilized PBMCs results in the simultaneous generation of both a functional population of anti-viral T cells and Tregs thus illustrating a potential single therapeutic strategy for the treatment of both GvHD and CMV reactivation following allogeneic haematopoietic stem cell transplantation. The use of G-CSF-mobilized cells as a starting material for cell therapy manufacture represents a feasible approach to alleviating the many problems incurred with successive donations and procurement of cells from

Interactions between Ibrutinib and Anti-CD20 Antibodies: Competing Effects on the Outcome of Combination Therapy.

Science.gov (United States)

Skarzynski, Martin; Niemann, Carsten U; Lee, Yuh Shan; Martyr, Sabrina; Maric, Irina; Salem, Dalia; Stetler-Stevenson, Maryalice; Marti, Gerald E; Calvo, Katherine R; Yuan, Constance; Valdez, Janet; Soto, Susan; Farooqui, Mohammed Z H; Herman, Sarah E M; Wiestner, Adrian

2016-01-01

Clinical trials of ibrutinib combined with anti-CD20 monoclonal antibodies (mAb) for chronic lymphocytic leukemia (CLL) report encouraging results. Paradoxically, in preclinical studies, in vitro ibrutinib was reported to decrease CD20 expression and inhibit cellular effector mechanisms. We therefore set out to investigate effects of in vivo ibrutinib treatment that could explain this paradox. Patients received single-agent ibrutinib (420 mg daily) on an investigator-initiated phase II trial. Serial blood samples were collected pretreatment and during treatment for ex vivo functional assays to examine the effects on CLL cell susceptibility to anti-CD20 mAbs. We demonstrate that CD20 expression on ibrutinib was rapidly and persistently downregulated (median reduction 74%, day 28, P ibrutinib were less susceptible to anti-CD20 mAb-mediated complement-dependent cytotoxicity than pretreatment cells (median reduction 75%, P ibrutinib, providing a likely mechanism for the preserved C3d opsonization. In addition, ibrutinib significantly inhibited trogocytosis, a major contributor to antigen loss and tumor escape during mAb therapy. Our data indicate that ibrutinib promotes both positive and negative interactions with anti-CD20 mAbs, suggesting that successfully harnessing maximal antitumor effects of such combinations requires further investigation. ©2015 American Association for Cancer Research.

Development and Characterization of Mouse Monoclonal Antibodies Reactive with Chicken CD83

Science.gov (United States)

This study was carried out to develop and characterize mouse monoclonal antibodies (mAbs) against chicken CD83 (chCD83), a membrane-bound glycoprotein belonging to the immunoglobulin superfamily that is primarily expressed on mature dendritic cells (DCs). A recombinant chCD83/IgG4 fusion protein con...

Synergistic reversal of type 1 diabetes in NOD mice with anti-CD3 and interleukin-1 blockade

DEFF Research Database (Denmark)

Ablamunits, Vitaly; Henegariu, Octavian; Hansen, Jakob Bondo

2012-01-01

(ab')(2) fragments of anti-CD3 mAb with or without IL-1 receptor antagonist (IL-1RA), or anti-IL-1ß mAb. We studied the reversal of diabetes and effects of treatment on the immune system. Mice that received a combination of anti-CD3 mAb with IL-1RA showed a more rapid rate of remission of diabetes than......Inflammatory cytokines are involved in autoimmune diabetes: among the most prominent is interleukin (IL)-1ß. We postulated that blockade of IL-1ß would modulate the effects of anti-CD3 monoclonal antibody (mAb) in treating diabetes in NOD mice. To test this, we treated hyperglycemic NOD mice with F...... arginase expression in macrophages and dendritic cells, and had delayed adoptive transfer of diabetes. After 1 month, there were increased concentrations of IgG1 isotype antibodies and reduced intrapancreatic expression of IFN-¿, IL-6, and IL-17 despite normal splenocyte cytokine secretion. These studies...

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

Science.gov (United States)

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

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

Therapeutic Effect of CD4+CD25+ Regulatory T Cells Amplified In Vitro on Experimental Autoimmune Neuritis in Rats

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Feng-Jie Wang

2018-05-01

Full Text Available Background/Aims: This study aimed to explore whether the adoptive transfusion of autologous CD4+CD25+ regulatory T cells (CD4+CD25+ Tregs has a therapeutic effect on Experimental autoimmune neuritis (EAN model rats, and it provides new experimental and theoretical bases for the immunotherapy of Guillain-Barre syndrome (GBS. Methods: CD4+CD25+ Tregs were sorted from the spleens of rats using immunomagnetic bead separation techniques combined with flow cytometry. Their in vitro inhibitory function was determined using a lymphocyte proliferation inhibition test, and their purity was confirmed by flow cytometry. Cells were stimulated using CD3/CD28 monoclonal antibodies and were cultured in culture medium containing interleukin 2 (IL-2, transforming growth factor-β (TGF-β and rapamycin. After 15 days of amplification, CD4+CD25+ Tregs were collected and transfused into EAN model rats. Changes in the pathology and electron microscopical morphology of rat sciatic nerves in the normal group, untreated group, low-dose group (2 × 107 and high-dose group (4 × 107 were observed, and the expression of CD4+CD25+FOXP3 in peripheral blood in the four groups of rats was detected by flow cytometry. Results: Compared with rats in the untreated group, rats in the treatment groups had significantly reduced infiltration of inflammatory cells in the sciatic nerve, as well as myelin and axonal damage. Additionally, the CD4+CD25+ Tregs levels in peripheral blood were significantly higher than those in the untreated group (P< 0. 05. Moreover, the therapeutic effect became more significant with an increase in the dose of adoptive transfusion. Conclusion: Adoptive transfusion of CD4+CD25+ Tregs into EAN model rats has significant therapeutic effects.

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.

G-CSF/anti-G-CSF antibody complexes drive the potent recovery and expansion of CD11b+Gr-1+ myeloid cells without compromising CD8+ T cell immune responses

Science.gov (United States)

2013-01-01

Background Administration of recombinant G-CSF following cytoreductive therapy enhances the recovery of myeloid cells, minimizing the risk of opportunistic infection. Free G-CSF, however, is expensive, exhibits a short half-life, and has poor biological activity in vivo. Methods We evaluated whether the biological activity of G-CSF could be improved by pre-association with anti-G-CSF mAb prior to injection into mice. Results We find that the efficacy of G-CSF therapy can be enhanced more than 100-fold by pre-association of G-CSF with an anti-G-CSF monoclonal antibody (mAb). Compared with G-CSF alone, administration of G-CSF/anti-G-CSF mAb complexes induced the potent expansion of CD11b+Gr-1+ myeloid cells in mice with or without concomitant cytoreductive treatment including radiation or chemotherapy. Despite driving the dramatic expansion of myeloid cells, in vivo antigen-specific CD8+ T cell immune responses were not compromised. Furthermore, injection of G-CSF/anti-G-CSF mAb complexes heightened protective immunity to bacterial infection. As a measure of clinical value, we also found that antibody complexes improved G-CSF biological activity much more significantly than pegylation. Conclusions Our findings provide the first evidence that antibody cytokine complexes can effectively expand myeloid cells, and furthermore, that G-CSF/anti-G-CSF mAb complexes may provide an improved method for the administration of recombinant G-CSF. PMID:24279871

Different thresholds of T cell activation regulate FIV infection of CD4+CD25+ and CD4+CD25- cells

International Nuclear Information System (INIS)

Joshi, Anjali; Garg, Himanshu; Tompkins, Mary B.; Tompkins, Wayne A.

2005-01-01

Cellular activation plays an important role in retroviral replication. Previously, we have shown that CD4 + CD25 + T cells by the virtue of their partially activated phenotype represent ideal candidates for a productive feline immunodeficiency virus (FIV) infection. In the present study, we extended our previous observations with regard to FIV replication in CD4 + CD25 + and CD4 + CD25 - cells under different stimulation conditions. Both CD4 + CD25 + and CD4 + CD25 - cells remain latently infected in the absence of IL-2 or concanvalinA (ConA), respectively; harboring a replication competent provirus capable of reactivation several days post-infection. While CD4 + CD25 + cells require low levels of exogenous IL-2 and virus inputs for an efficient FIV replication, CD4 + CD25 - T cells can only be productively infected in the presence of either high concentrations of IL-2 or high virus titers, even in the absence of mitogenic stimulation. Interestingly, while high virus input activates CD4 + CD25 - cells to replicate FIV, it induces apoptosis in a high percentage of CD4 + CD25 + T cells. High IL-2 concentrations but not high virus inputs lead to surface upregulation of CD25 and significant cellular proliferation in CD4 + CD25 - cells. These results suggest that CD4 + CD25 + and CD4 + CD25 - T cells have different activation requirements which can be modulated by both viral and cytokine stimuli to reach threshold activation levels in order to harbor a productive FIV infection. This holds implications in vivo for CD4 + CD25 + and CD4 + CD25 - cells to serve as potential reservoirs of a productive and latent FIV infection

Durvalumab: an investigational anti-PD-L1 monoclonal antibody for the treatment of urothelial carcinoma

Directory of Open Access Journals (Sweden)

Faiena I

2018-01-01

Full Text Available Izak Faiena,1,2 Amy L Cummings,3 Anna M Crosetti,3 Allan J Pantuck,1,2 Karim Chamie,1,2 Alexandra Drakaki1–3 1Department of Urology, 2Institute of Urologic Oncology, 3Department of Medicine, Division of Hematology and Oncology, David Geffen School of Medicine at University of California, Los Angeles, CA, USA Abstract: Our expanding knowledge of immunotherapy for solid tumors has led to an explosion of clinical trials aimed at urothelial carcinoma. The primary strategy is centered on unleashing the immune system by releasing the inhibitory signals propagated by programmed cell death-1 (PD-1 and its ligand programmed cell death ligand-1 (PD-L1. Many antibody constructs have been developed to block these interactions and are used in clinical trials. The Food and Drug Administration has already approved a number of checkpoint inhibitors such as anti-cytotoxic T-lymphocyte-associated protein 4 (CTLA4 monoclonal antibodies including ipilimumab; anti-PD-1 monoclonal antibodies including nivolumab and pembrolizumab; anti-PD-L1 antibodies including atezolizumab, avelumab, and durvalumab. One of the latest inhibitors is durvalumab, which is a high-affinity human immunoglobulin G1 kappa monoclonal antibody and blocks the interaction of PD-L1 with PD-1 and CD80. Currently, there are a number of ongoing trials in advanced urothelial carcinoma both using durvalumab monotherapy and in combination with other targeted therapies. In addition, durvalumab is being investigated in the non-muscle-invasive urothelial carcinoma, which is centered around intravenous formulations. These exciting developments have added a significant number of therapies in a previously limited treatment landscape. Keywords: durvalumab, checkpoint inhibitors, metastatic urothelial carcinoma

HuMax-CD4

DEFF Research Database (Denmark)

Skov, Lone; Kragballe, Knud; Zachariae, Claus

2003-01-01

BACKGROUND: Psoriasis is characterized by infiltration with mononuclear cells. Especially activated memory CD4+ T cells are critical in the pathogenesis. Interaction between the CD4 receptor and the major histocompatibility complex class II molecule is important for T-cell activation. OBJECTIVE......: To test safety and efficacy of a fully human monoclonal anti-CD4 antibody (HuMax-CD4) in the treatment of psoriasis. DESIGN: Multicenter, double-blind, placebo-controlled, randomized clinical trial. Patients Eighty-five patients with moderate to severe psoriasis. INTERVENTIONS: Subcutaneous infusions...... dose level, 6 (38%) of 16 patients obtained more than 25% reduction of PASI and 3 (19%) obtained more than 50% reduction of PASI. A dose-dependent decrease in total lymphocyte count was seen and was parallel to a dose-dependent decrease in CD4+ T cells. This decrease was due to a decrease in the memory...

Long- and short-term exposure to PM2.5 and mortality: using novel exposure models.

Science.gov (United States)

Kloog, Itai; Ridgway, Bill; Koutrakis, Petros; Coull, Brent A; Schwartz, Joel D

2013-07-01

Many studies have reported associations between ambient particulate matter (PM) and adverse health effects, focused on either short-term (acute) or long-term (chronic) PM exposures. For chronic effects, the studied cohorts have rarely been representative of the population. We present a novel exposure model combining satellite aerosol optical depth and land-use data to investigate both the long- and short-term effects of PM2.5 exposures on population mortality in Massachusetts, United States, for the years 2000-2008. All deaths were geocoded. We performed two separate analyses: a time-series analysis (for short-term exposure) where counts in each geographic grid cell were regressed against cell-specific short-term PM2.5 exposure, temperature, socioeconomic data, lung cancer rates (as a surrogate for smoking), and a spline of time (to control for season and trends). In addition, for long-term exposure, we performed a relative incidence analysis using two long-term exposure metrics: regional 10 × 10 km PM2.5 predictions and local deviations from the cell average based on land use within 50 m of the residence. We tested whether these predicted the proportion of deaths from PM-related causes (cardiovascular and respiratory diseases). For short-term exposure, we found that for every 10-µg/m increase in PM 2.5 exposure there was a 2.8% increase in PM-related mortality (95% confidence interval [CI] = 2.0-3.5). For the long-term exposure at the grid cell level, we found an odds ratio (OR) for every 10-µg/m increase in long-term PM2.5 exposure of 1.6 (CI = 1.5-1.8) for particle-related diseases. Local PM2.5 had an OR of 1.4 (CI = 1.3-1.5), which was independent of and additive to the grid cell effect. We have developed a novel PM2.5 exposure model based on remote sensing data to assess both short- and long-term human exposures. Our approach allows us to gain spatial resolution in acute effects and an assessment of long-term effects in the entire population rather than a

Epidermal growth factor receptor inhibition by anti-CD147 therapy in cutaneous squamous cell carcinoma.

Science.gov (United States)

Frederick, John W; Sweeny, Larissa; Hartman, Yolanda; Zhou, Tong; Rosenthal, Eben L

2016-02-01

Advanced cutaneous squamous cell carcinoma (SCC) is an uncommon and aggressive malignancy. As a result, there is limited understanding of its biology and pathogenesis. CD147 and epidermal growth factor receptor (EGFR) have been identified as oncologically important targets, but their relationship remains undefined in cutaneous SCC. Multiple cutaneous SCC cell lines (Colo-16, SRB-1, and SRB-12), were treated in vitro with a range of chimeric anti-CD147 monoclonal antibody (mAb) (0, 50, 100, and 200 µg/mL) or transfected with a small interfering RNA against CD147 (SiCD147). Cell proliferation, migration (scratch wound healing assay), and protein expression was then assessed. In vivo, Colo-16 flank xenografts were treated anti-CD147 mAb (150 µg i.p. triweekly). After treatment with anti-CD147 (200 µg/mL), there was a significant decrease in proliferation for all cell lines relative to controls (p CD147 (200 µg/mL) resulted in decreased cell migration for all cell lines, with an average of 43% reduction in closure compared to controls (p CD147 antibody therapy and siRNA mediated reduction in CD147 expression were both found to decrease protein expression of EGFR, which correlated with a reduction in downstream total and phosphorylated protein kinase B (pAKT). Tumor growth in vivo was reduced for both the anti-CD147 treatment group and the SiCD147 group relative to controls. Inhibition and downregulation of CD147 in cutaneous SCC resulted in suppression of the malignant phenotype in vitro and in vivo, which may be mediated in part by an alteration in EGFR expression. As a result, CD147 may serve as a potential therapeutic target for advanced cutaneous SCC. © 2014 Wiley Periodicals, Inc.

Characterisation of CD4 T cells in healthy and diseased koalas (Phascolarctos cinereus) using cell-type-specific monoclonal antibodies.

Science.gov (United States)

Mangar, Chandan; Armitage, Charles W; Timms, Peter; Corcoran, Lynn M; Beagley, Kenneth W

2016-07-01

The koala (Phascolarctos cinereus) is an arboreal herbivorous marsupial that is an Australian icon. Koalas in many parts of Australia are under multiple threats including habitat destruction, dog attacks, vehicular accidents, and infectious diseases such as Chlamydia spp. and the koala retrovirus (KoRV), which may contribute to the incidence of lymphoma and leukaemia in this species. Due to a lack of koala-specific immune reagents and assays there is currently no way to adequately analyse the immune response in healthy, diseased or vaccinated animals. This paper reports the production and characterisation of the first anti-koala CD4 monoclonal antibody (mAb). The koala CD4 gene was identified and used to develop recombinant proteins for mAb production. Fluorochrome-conjugated anti-CD4 mAb was used to measure the levels of CD4(+) lymphocytes collected from koala spleens (41.1%, range 20-45.1%) lymph nodes (36.3%, range 19-55.9%) and peripheral blood (23.8%, range 17.3-35%) by flow cytometry. Biotin-conjugated anti-CD4 mAb was used for western blot to determine an approximate size of 52 kDa for the koala CD4 molecule and used in immunohistochemistry to identify CD4(+) cells in the paracortical region and germinal centres of spleen and lymph nodes. Using the anti-CD4 mab we showed that CD4 cells from vaccinated, but not control, koalas proliferated following in vitro stimulation with UV-inactivated Chlamydia pecorum and recombinant chlamydial antigens. Since CD4(+) T cells have been shown to play a pivotal role in clearing chlamydial infection in both human and mouse infections, using this novel antibody will help determine the role CD4(+) T cells play in protection against chlamydial infection in koalas and also enhance our knowledge of how KoRV affects the koala immune system. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

International Nuclear Information System (INIS)

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

2005-01-01

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

TNFR2 expression on CD25hiFOXP3+ T cells induced upon TCR stimulation of CD4 T cells identifies maximal cytokine-producing effectors.

Directory of Open Access Journals (Sweden)

Chindu eGovindaraj

2013-08-01

Full Text Available In this study, we show that CD25hiTNFR2+ cells can be rapidly generated in vitro from circulating CD4 lymphocytes by polyclonal stimuli anti-CD3 in the presence of anti-CD28. The in vitro induced CD25hiTNFR2+ T cells express a conventional Treg phenotype FOXP3+CTLA4+CD127lo/-, but produce effector and immunoregulatory cytokines including IL-2, IL-10 and IFN-g. These induced CD25hiTNFR2+ T cells do not suppress target cell proliferation, but enhance it instead. Thus the CD25hiTNFR2+ phenotype induced rapidly following CD3/28 cross linking of CD4 T cells identifies cells with maximal proliferative and effector cytokine producing capability. The in vivo counterpart of this cell population may play an important role in immune response initiation.

The role of Foxp3+ regulatory T cells in liver transplant tolerance.

Science.gov (United States)

Li, W; Carper, K; Zheng, X X; Kuhr, C S; Reyes, J D; Liang, Y; Perkins, D L; Thomson, A W; Perkins, J D

2006-12-01

The liver has long been considered a tolerogenic organ that favors the induction of peripheral tolerance. The mechanisms underlying liver tolerogenicity remain largely undefined. In this study, we characterized Foxp3-expressing CD4+ CD25+ regulatory T cells (Treg) in liver allograft recipients and examined the role of Treg in inherent liver tolerogenicity by employing the mouse spontaneous liver transplant tolerance model. Orthotopic liver transplantation was performed from C57BL/10 (H2b) to C3H/HeJ (H2k) mice. The percentage of CD4+ CD25+ Treg was expanded in the liver grafts and recipient spleens from day 5 up to day 100 posttransplantation, associated with high intracellular Foxp3 and CTLA4 expression. Immunohistochemistry further demonstrated significant numbers of Foxp3+ cells in the liver grafts and recipient spleens and increased transforming growth factor beta expression in the recipient spleens throughout the time courses. Adoptive transfer of spleen cells from the long-term liver allograft survivors significantly prolonged donor heart graft survival. Depletion of recipient CD4+ CD25+ Treg using anti-CD25 monoclonal antibody (250 microg/d) induced acute liver allograft rejection, associated with elevated anti-donor T-cell proliferative responses, CTL and natural killer activities, enhanced interleukin (IL)-2, interferon-gamma, IL-10, and decreased IL-4 production, and decreased T-cell apoptotic activity in anti-CD25-treated recipients. Moreover, CTLA4 blockade by anti-CTLA4 monoclonal antibody administration exacerbated liver graft rejection when combined with anti-CD25 monoclonal antibody. Thus, Foxp3+ CD4+ CD25+ Treg appear to underpin spontaneous acceptance of major histocompatability complex- mismatched liver allografts in mice. CTLA4, IL-4, and apoptosis of alloreactive T cells appear to contribute to the function of Treg and regulation of graft outcome.

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

International Nuclear Information System (INIS)

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

1990-01-01

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

Anti-human CD73 monoclonal antibody inhibits metastasis formation in human breast cancer by inducing clustering and internalization of CD73 expressed on the surface of cancer cells

DEFF Research Database (Denmark)

Terp, Mikkel G; Olesen, Kristina A; Christensen, Eva Arnspang

2013-01-01

-linking of CD73, because both whole IgG anti-CD73 AD2 mAb and Fab' fragments thereof exhibited this effect. Ex vivo treatment of different breast cancer cell lines with anti-CD73 AD2 mAb before i.v. injection into mice inhibited extravasation/colonization of circulating tumor cells and significantly reduced...

The different clinical effects of anti-BLyS, anti-APRIL and anti-CD20 antibodies point at a critical pathogenic role of γ-herpesvirus infected B cells in the marmoset EAE model.

Science.gov (United States)

Anwar Jagessar, S; Fagrouch, Zahra; Heijmans, Nicole; Bauer, Jan; Laman, Jon D; Oh, Luke; Migone, Thi; Verschoor, Ernst J; 't Hart, Bert A

2013-06-01

The robust and rapid clinical effect of depleting anti-CD20 monoclonal antibodies (mAb) in multiple sclerosis (MS) demonstrates a critical pathogenic contribution of B cells. The clinical effect of anti-CD20 mAb has been replicated in a relevant preclinical MS model, experimental autoimmune encephalomyelitis (EAE) in marmoset monkeys (Callithrix jacchus). By contrast, treatment with mAbs against two essential cytokines in B cell activation growth and survival, i.e. BlyS/BAFF and APRIL, was only partially effective. All three mAbs induced depletion of CD20+ B cells from the circulation, albeit with different kinetics and based on distinct mechanisms of action. In the current study we analyzed whether the different clinical effect of anti-CD20 mAb or the anti-BLyS and anti-APRIL mAbs is due to different depletion of B cells infected with the EBV of marmosets, CalHV3. Employing a novel PCR-based assay, half of the colony of group-housed marmosets was tested positive for CalHV3 DNA in secondary lymphoid organs. The same prevalence was observed in placebo-treated monkeys. In marmosets treated with anti-CD20 mAb the load of CalHV3 DNA in lymphoid organs was substantially reduced, while this was not observed in the monkeys treated with anti-BLyS or anti-APRIL mAbs. To examine the pathogenic role of virus-transformed B cells, we infused EBV-transformed B lymphoblastic cell (BLC) lines presenting the immunodominant MOG34-56 peptide. We observed in the recipients of MOG34-56 pulsed BLC, but not in their fraternal siblings infused with non-pulsed BLC, activation of anti-MOG34-56 T cells and meningeal inflammation. Collectively, the data show that among CD20+ B cells, the herpesvirus-transformed subset has a particularly important pathogenic role in the marmoset EAE model.

Early post-transplant immune monitoring can predict long-term kidney graft survival: soluble CD30 levels, anti-HLA antibodies and IgA-anti-Fab autoantibodies.

Science.gov (United States)

Amirzargar, Mohammad Ali; Amirzargar, Aliakbar; Basiri, Abbas; Hajilooi, Mehrdad; Roshanaei, Ghodratollah; Rajabi, Gholamreza; Mohammadiazar, Sina; Solgi, Ghasem

2014-01-01

This study aimed to investigate the predictive power of anti-HLA antibodies, sCD30 levels and IgA-anti-Fab autoantibody before and early after transplantation in relation to long-term kidney allograft survival. Pre- and post-transplant sera samples of 59 living-unrelated donor kidney recipients were tested for above risk factors by enzyme-linked immunoabsorbent assay. 15 out of 59 cases experienced rejection episodes (failure group). Pre- and post-transplant high sCD30 levels were significantly associated with graft failure (P=0.02 and P=0.004) and decreased 4 year graft survival (P = 0.009 and P = 0.001). Higher frequency of post-transplant HLA class-II antibody in the absence of class-I antibody was observed in failure group (P=0.007). Patients with post-transplant HLA class-I and class-II antibodies either alone or in combination showed significant lower 4 year graft survival. Recipients with high sCD30 levels in the presence of HLA class-I or class-II antibodies within 2 weeks post-transplant had poor graft survival (P = 0.004 and P = 0.002, respectively). High levels of post-transplant IgA-anti-Fab antibody was more frequent in functioning-graft patients (P = 0.00001), correlated with decreased serum creatinine levels (P = 0.01) and associated with improved graft survival (P = 0.008). Our findings indicate the deleterious effect of early post-transplant HLA antibodies and increased sCD30 levels dependently and protective effect of IgA-anti-Fab antibodies on long-term renal graft outcomes. Copyright © 2013 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

Effects of anti-CD40 mAb on inducing malignant B cells proliferation arrest and apoptosis and its mechanism

International Nuclear Information System (INIS)

Tang Lin; Zhuang Yumei; Zhou Zhaohua; Yu Gehua; Pan Jianzhong; Zhang Xueguang

2002-01-01

Objective: To study the expression of CD 40 molecule and the biological effects mediated by CD 40 molecules on malignant B cells. Methods: Agonistic anti-human CD 40 monoclonal antibody (clone 5C11) was added to cell culture system. Cell counting, PI staining, Annexin-V staining and flow cytometric analysis were used to study the behavior of malignant B cell lines after treatment with mAb clone 5C11. Results: 5C11 induced homotypic aggregation and proliferation arrest and mediated apoptosis in multiple myeloma cell line XG2 that expressed CD 40 strongly; 5C11 induced B lymphoma cell line Daudi homotypic aggregation and proliferation arrest and apoptosis, the apoptosis of XG2 and Daudi by CD40 activation was not mediated by TNF. Conclusion: Agonistic anti-CD 40 mAb 5C11 can inhibit the proliferation of malignant B cells by inducing them to die apoplectically

Use of radiolabeled monoclonal anti-B1 antibody for B lymphocyte imaging in Rhesus monkeys

International Nuclear Information System (INIS)

Letvin, N.L.; Zalutsky, M.R.; Chalifoux, L.V.; Atkins, H.L.

1987-01-01

Imaging tissues rich in B lymphocytes in man using a radiolabeled monoclonal anti-B cell antibody would be extremely useful in the clinical staging of non-Hodgkins lymphomas. Studies were done in rhesus monkeys using radiolabeled monoclonal anti-B1 antibody to determine the feasibility of such an approach. Immunohistologic studies demonstrated that infused monoclonal anti-B1 binds in vivo with specificity to B cells in lymph nodes and spleen. The kinetics of clearance of 131 I-labeled anti-B1 were determined. The B lymphocyte-rich spleen could be readily visualized by gamma camera scanning without significant background and without the need for image intensification or blood background subtraction techniques. These data support the feasibility of using anti-B1 for staging B cell lymphomas in man. (author)

Inhibition of VEGF-dependent angiogenesis by the anti-CD82 monoclonal antibody 4F9 through regulation of lipid raft microdomains

International Nuclear Information System (INIS)

Nomura, Sayaka; Iwata, Satoshi; Hatano, Ryo; Komiya, Eriko; Dang, Nam H.; Iwao, Noriaki; Ohnuma, Kei; Morimoto, Chikao

2016-01-01

CD82 (also known as KAI1) belongs to the tetraspanin superfamily of type III transmembrane proteins, and is involved in regulating cell adhesion, migration and proliferation. In contrast to these well-established roles of CD82 in tumor biology, its function in endothelial cell (EC) activity and tumor angiogenesis is yet to be determined. In this study, we show that suppression of CD82 negatively regulates vascular endothelial growth factor (VEGF)-induced angiogenesis. Moreover, we demonstrate that the anti-CD82 mAb 4F9 effectively inhibits phosphorylation of VEGF receptor 2 (VEGFR2), which is the principal mediator of the VEGF-induced angiogenic signaling process in tumor angiogenesis, by regulating the organization of the lipid raft microdomain signaling platform in human EC. Our present work therefore suggests that CD82 on EC is a potential target for anti-angiogenic therapy in VEGFR2-dependent tumor angiogenesis. -- Highlights: •Knockdown of CD82 decreases EC migration, proliferation and angiogenesis. •Anti-CD82 mAb 4F9 inhibits EC migration, proliferation and angiogenesis. •4F9 inhibits VEGFR2 phosphorylation via control of CD82 distribution in lipid rafts.

Inhibition of VEGF-dependent angiogenesis by the anti-CD82 monoclonal antibody 4F9 through regulation of lipid raft microdomains

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Nomura, Sayaka; Iwata, Satoshi; Hatano, Ryo [Division of Clinical Immunology, Advanced Clinical Research Center, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo, 108-8639 (Japan); Komiya, Eriko [Department of Therapy Development and Innovation for Immune Disorders and Cancers, Graduate School of Medicine, Juntendo University, 2-1-1, Hongo, Bunkyo-ku, Tokyo, 113-8421 (Japan); Dang, Nam H. [Division of Hematology/Oncology, University of Florida, 1600 SW Archer Road- Box 100278, Room MSB M410A, Gainesville, FL, 32610 (United States); Iwao, Noriaki [Department of Hematology, School of Medicine, Juntendo University, 2-1-1, Hongo, Bunkyo-ku, Tokyo, 113-8421 (Japan); Ohnuma, Kei, E-mail: kohnuma@juntendo.ac.jp [Department of Rheumatology and Allergy, IMSUT Hospital, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo, 108-8639 (Japan); Morimoto, Chikao [Division of Clinical Immunology, Advanced Clinical Research Center, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo, 108-8639 (Japan); Department of Rheumatology and Allergy, IMSUT Hospital, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo, 108-8639 (Japan)

2016-05-20

CD82 (also known as KAI1) belongs to the tetraspanin superfamily of type III transmembrane proteins, and is involved in regulating cell adhesion, migration and proliferation. In contrast to these well-established roles of CD82 in tumor biology, its function in endothelial cell (EC) activity and tumor angiogenesis is yet to be determined. In this study, we show that suppression of CD82 negatively regulates vascular endothelial growth factor (VEGF)-induced angiogenesis. Moreover, we demonstrate that the anti-CD82 mAb 4F9 effectively inhibits phosphorylation of VEGF receptor 2 (VEGFR2), which is the principal mediator of the VEGF-induced angiogenic signaling process in tumor angiogenesis, by regulating the organization of the lipid raft microdomain signaling platform in human EC. Our present work therefore suggests that CD82 on EC is a potential target for anti-angiogenic therapy in VEGFR2-dependent tumor angiogenesis. -- Highlights: •Knockdown of CD82 decreases EC migration, proliferation and angiogenesis. •Anti-CD82 mAb 4F9 inhibits EC migration, proliferation and angiogenesis. •4F9 inhibits VEGFR2 phosphorylation via control of CD82 distribution in lipid rafts.

Use of CD25 as an immunohistochemical marker for acquired ocular toxoplasmosis

Directory of Open Access Journals (Sweden)

Cristina Miyamoto

2010-10-01

Full Text Available PURPOSE: Toxoplasmosis is the most common cause of posterior infectious uveitis worldwide. It is often impossible to determine its congenital or acquired nature. Interleukin-2 (IL-2 in peripheral blood has been described as a possible marker for acquired toxoplasmosis. The purpose of this study is to evaluate the histopathological characteristics of ocular toxoplasmosis cases using CD25 as a marker for the expression of interleukin-2. METHODS: Ten formalin-fixed, paraffin-embedded enucleated globes from ten immunocompetent patients with clinical diagnosis of toxoplasmosis were evaluated. Four patients had the acquired form of ocular toxoplasmosis (positive IgM while six were IgM negative and IgG positive for toxoplasmosis. Histopathological slides were reviewed for the extension of the retinal necrosis, number of toxo cysts, the granulomatous inflammatory reaction, the presence of T and B cells within the choroid and the IL-2 expression. Immunohistochemistry using monoclonal antibodies was performed to observe the expression of CD4, CD8, CD20, CD25, and CD68. RESULTS: The histopathological evaluation disclosed no differences between acquired and the other ocular toxoplasmosis cases regarding the characteristics studied. However, CD25 showed a higher expression of IL-2 on the 4 acquired cases of ocular toxoplasmosis compared to the remainders. CONCLUSIONS: To the best of our knowledge, this is the first report showing that the use of CD25 as a marker for interleukin-2 could differentiate acquired ocular toxoplasmosis.

Critical assessment of the efficiency of CD34 and CD133 antibodies for enrichment of rabbit hematopoietic stem cells.

Science.gov (United States)

Vašíček, Jaromír; Shehata, Medhat; Schnabl, Susanne; Hilgarth, Martin; Hubmann, Rainer; Jäger, Ulrich; Bauer, Miroslav; Chrenek, Peter

2018-06-08

Rabbits have many hereditary diseases common to humans and are therefore a valuable model for regenerative disease and hematopoietic stem cell (HSC) therapies. Currently, there is no substantial data on the isolation and/or enrichment of rabbit HSCs. This study was initiated to evaluate the efficiency of the commercially available anti-CD34 and anti-CD133 antibodies for the detection and potential enrichment of rabbit HSCs from peripheral blood. PBMCs from rabbit and human blood were labelled with different clones of anti-human CD34 monoclonal antibodies (AC136, 581 and 8G12) and rabbit polyclonal CD34 antibody (pCD34) and anti-human CD133 monoclonal antibodies (AC133 and 293C3). Flow cytometry showed a higher percentage of rabbit CD34 + cells labelled by AC136 in comparison to the clone 581 and pCD34 (Penrichment of rabbit CD34 + cells using magnetic-activated cell sorting (MACS). The enrichment of the rabbit CD34 + cells after sorting was low in comparison to human samples (2.4% vs. 39.6%). PCR analyses confirmed the efficient enrichment of human CD34 + cells and the low expression of CD34 mRNA in rabbit positive fraction. In conclusion, the tested antibodies might be suitable for detection, but not for sorting the rabbit CD34 + HSCs and new specific anti-rabbit CD34 antibodies are needed for efficient enrichment of rabbit HSCs. This article is protected by copyright. All rights reserved. © 2018 American Institute of Chemical Engineers.

Dosimetric studies of anti-CD20 labeled with therapeutic radionuclides at IPEN/CNEN-SP

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Barrio, G.; Dias, C.R.B.R.; Osso Junior, J.A., E-mail: gracielabarrio@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2012-07-01

Radioimmunotherapy (RIT) makes use of monoclonal antibodies (MAb) labeled with alpha/beta radionuclides for therapeutical purposes, leading to tumor irradiation and destruction, preserving the normal organs on the radiation excess. The therapeutic activity to be injected in a specific patient is based on information obtained in dosimetric studies. Beta emitting radionuclides such as {sup 131}I, {sup 188}Re, {sup 90}Y, {sup 177}Lu and {sup 166}Ho are useful for the development of therapeutic radiopharmaceuticals. Anti-CD20 (Rituximab) is a chimeric MAb directed against antigen surface CD20 on B-lymphocytes, used in non-Hodgkin lymphoma treatment (NHL). The association with beta radionuclides have shown greater therapeutic efficacy. Currently, two radiopharmaceuticals with Anti-CD20 for radioimmunotherapy have FDA approval for NHL treatment: {sup 131}I-AntiCD20 (Bexar) and {sup 90}Y-AntiCD20 (Zevalin). Techniques for the radiolabeling of {sup 188}Re-antiCD20 have been recently developed by IPEN-CNEN/SP in order to evaluate the clinical use of this radionuclide in particular. The use of {sup 188}Re (T{sub 1/2} 17h) produced by the decay of {sup 188}W (T{sub 1/2} 69d), from an {sup 188}W/{sup 188}Re generator system, has represented an alternative to RIT. Beyond high energy beta emission for therapy, {sup 188}Re also emits gamma rays (155keV) suitable for image. The aim of this new project is to compare the labeling of anti-CD20 with {sup 188}Re with the same MAb labeled with {sup 131}I, {sup 177}Lu, {sup 90}Y and even {sup 99m}Tc. The first step in this project is the review of the published data available concerning the labeling of this MAb with different radionuclides, along with data obtained at IPEN, taking into account labeling procedures, labeling yields, reaction time, level and kind of impurities and biodistribution studies. The pharmacokinetic code will be developed in Visual Studio.NET platform through VB.NET and C{sup ++} for biodistribution and dosimetric

Anomalous expression of Thy1 (CD90) in B-cell lymphoma cells and proliferation inhibition by anti-Thy1 antibody treatment

International Nuclear Information System (INIS)

Ishiura, Yoshihito; Kotani, Norihiro; Yamashita, Ryusuke; Yamamoto, Harumi; Kozutsumi, Yasunori; Honke, Koichi

2010-01-01

The anti-CD20 monoclonal antibody (Ab) rituximab is accepted to be an effective therapeutic Ab for malignant B-cell lymphoma; however, discovery of other cell surface antigens is required for the option of antibody medicine. Considering that many tumor-associated antigens are glycans, we have searched glycoconjugates for the candidate antigens that therapeutic Abs target. To this end, we first focused on the difference in the glycogenes expression in terms of Epstein-Barr virus (EBV) infection of a Burkitt's lymphoma cell line, Akata. Using DNA array, flow cytometry and Western blotting, we found that Thy1 was highly expressed in EBV-positive Akata cells. Subsequently, Thy1 was found to be expressed in other B-cell lymphoma cell lines: BJAB, MutuI, and MutuIII, irrespective of EBV infection. Treatment of these cells with an anti-Thy1 monoclonal antibody inhibited proliferation more strongly than the therapeutic Ab rituximab. The B-cell lymphoma cell lines were classified based on the extent of the proliferation inhibition, which was not correlated with the expression level of Thy1. It is suggested that stable residence of receptor tyrosine kinases in lipid rafts sustains cell growth in B-cell lymphoma cells.

Preparation of the radiopharmaceutical {sup 131}I-Anti-CD20 for the treatment of lymphomas; Preparacion del radiofarmaco {sup 131}I-Anti-CD20 para el tratamiento de linfomas

Energy Technology Data Exchange (ETDEWEB)

Pantoja H, I E

2004-07-01

At the present time they are considered to the lymphomas like a problem of first magnitude since has happened it is necessary to be the fifth cancer cause in the world. Different treatments focused to the lymphoma like the chemotherapy and the radiotherapy, have been employees to counteract the No-Hodgkin lymphoma, without these they don't exclude the healthy tissue of the toxicity. It is for it that is taking a new direction with the employment of the directed radioimmunotherapy since this it allows to kill wicked cells selectively with radiation dose joined to the apoptosis and cytotoxicity induced by the own one bio molecule. The radioimmunotherapy with radiolabelled antibodies directed to the surface antigen CD20 represents a new modality for the treatment of No-Hodgkin lymphoma and potentially other illnesses. In this work the parameters of optimization are presented for the preparation, control of quality and evaluation of the stability in vitro and in vivo of the monoclonal antibody anti-CD20 labelled with {sup 131} I for the treatment of No-Hodgkin lymphoma. The anti-CD20 labelled by the chloramine-T method with high radiochemical purity (>98%), it is stable in solution for but of a half life of the radionuclide (8.04 days) The {sup 131} I-anti-CD20 doesn't present dehalogenation in vitro (human serum) during 24 h of incubation at 37 C. According to the tests carried out to establish the immunoreactivity, a percentage of union to cells was obtained (B lymphocytes) bigger to 30%. The biodistribution in mice balb/c one hour after their administration, it shows that there is not high reception in mucous neither kidneys, what indicates that the complex is stable in vivo. In conclusion, the radiopharmaceutical {sup 131} I-anti-CD20 was obtained in sterile injectable solution and free of pyrogens with a radiochemical purity bigger to 98% and a specific activity of 296 MBq. The radiolabelled molecule maintains its biological recognition for the receiving CD20

TLR5 signaling enhances the proliferation of human allogeneic CD40-activated B cell induced CD4hiCD25+ regulatory T cells.

Directory of Open Access Journals (Sweden)

Ping-Lung Chan

Full Text Available Although diverse functions of different toll-like receptors (TLR on human natural regulatory T cells have been demonstrated recently, the role of TLR-related signals on human induced regulatory T cells remain elusive. Previously our group developed an ex vivo high-efficient system in generating human alloantigen-specific CD4(hiCD25(+ regulatory T cells from naïve CD4(+CD25(- T cells using allogeneic CD40-activated B cells as stimulators. In this study, we investigated the role of TLR5-related signals on the generation and function of these novel CD4(hiCD25(+ regulatory T cells. It was found that induced CD4(hiCD25(+ regulatory T cells expressed an up-regulated level of TLR5 compared to their precursors. The blockade of TLR5 using anti-TLR5 antibodies during the co-culture decreased CD4(hiCD25(+ regulatory T cells proliferation by induction of S phase arrest. The S phase arrest was associated with reduced ERK1/2 phosphorylation. However, TLR5 blockade did not decrease the CTLA-4, GITR and FOXP3 expressions, and the suppressive function of CD4(hiCD25(+ regulatory T cells. In conclusion, we discovered a novel function of TLR5-related signaling in enhancing the proliferation of CD4(hiCD25(+ regulatory T cells by promoting S phase progress but not involved in the suppressive function of human CD40-activated B cell-induced CD4(hiCD25(+ regulatory T cells, suggesting a novel role of TLR5-related signals in the generation of induced regulatory T cells.

Verification of responses of Japanese medaka (Oryzias latipes) to anti-androgens, vinclozolin and flutamide, in short-term assays.

Science.gov (United States)

Nakamura, Ataru; Takanobu, Hitomi; Tamura, Ikumi; Yamamuro, Masumi; Iguchi, Taisen; Tatarazako, Norihisa

2014-05-01

Various testing methods for the detection of the endocrine disruptive activities of chemicals have been developed in freshwater fish species. However, a few relatively easier specific methods for detecting anti-androgenic activities are available for fish. The aim of this study was to verify the papillary process in Japanese medaka (Oryzias latipes) as an indicator of the anti-androgenic activity of chemicals. Japanese medaka were exposed to two types of anti-androgenic compounds, vinclozolin and flutamide, using two short-term assays; one was conformed to the existing short-term reproduction assay using adult fish (adult test) and the other was a test based on the same methods but using juvenile fish at the beginning of exposure (juvenile test). Significant decreases in male papillary processes were observed in the juvenile test treated with the highest concentration of both antiandrogens (640 µg l(-1) vinclozolin and 1000 µg l(-1) flutamide); however, no significant effects were observed in the adult test. Consequently, our results indicate that papillary processes in Japanese medaka can be used as the end-point for screening the anti-androgenic activity of chemicals using juvenile fish for a specific period based on the existing short-term reproduction assay. Copyright © 2013 John Wiley & Sons, Ltd.

Monoclonal anti-melanoma antibodies and their possible clinical use

International Nuclear Information System (INIS)

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

1985-01-01

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

Function and regulation of LAG3 on CD4+CD25- T cells in non-small cell lung cancer.

Science.gov (United States)

Ma, Qin-Yun; Huang, Da-Yu; Zhang, Hui-Jun; Wang, Shaohua; Chen, Xiao-Feng

2017-11-15

LAG3 is a surface molecule found on a subset of immune cells. The precise function of LAG3 appears to be context-dependent. In this study, we investigated the effect of LAG3 on CD4 + CD25 - T cells from non-small cell lung cancer (NSCLC) patients. We found that in the peripheral blood mononuclear cells of NSCLC patients, LAG3 was significantly increased in CD4 + T cells directly ex vivo and primarily in the CD4 + CD25 - fraction, which was regulated by prolonged TCR stimulation and the presence of IL-27. TCR stimulation also increased CD25 expression, but not Foxp3 expression, in LAG3-expressing CD4 + CD25 - cells Compared to LAG3-nonexpressing CD4 + CD25 - cells, LAG3-expressing CD4 + CD25 - cells presented significantly higher levels of PD1 and TIM3, two inhibitory receptors best described in exhausted CD8 + T effector cells. LAG3-expressing CD4 + CD25 - cells also presented impaired proliferation compared with LAG3-nonexpressing CD4 + CD25 - cells but could be partially rescued by inhibiting both PD1 and TIM3. Interestingly, CD8 + T cells co-incubated with LAG3-expressing CD4 + CD25 - cells at equal cell numbers demonstrated significantly lower proliferation than CD8 + T cells incubated alone. Co-culture with CD8 + T cell and LAG3-expressing CD4 + CD25 - T cell also upregulated soluble IL-10 level in the supernatant, of which the concentration was positively correlated with the number of LAG3-expressing CD4 + CD25 - T cells. In addition, we found that LAG3-expressing CD4 + CD25 - T cells infiltrated the resected tumors and were present at higher frequencies of in metastases than in primary tumors. Taken together, these data suggest that LAG3-expressing CD4 + CD25 - T cells represent another regulatory immune cell type with potential to interfere with anti-tumor immunity. Copyright © 2017 Elsevier Inc. All rights reserved.

Identification and Functional Characterization of Human Cd4+Cd25+ T Cells with Regulatory Properties Isolated from Peripheral Blood

Science.gov (United States)

Jonuleit, Helmut; Schmitt, Edgar; Stassen, Michael; Tuettenberg, Andrea; Knop, Jurgen; Enk, Alexander H.

2001-01-01

A subpopulation of peripheral human CD4+CD25+ T cells that expresses CD45RO, histocompatibility leukocyte antigen DR, and intracellular cytotoxic T lymphocyte–associated antigen (CTLA) 4 does not expand after stimulation and markedly suppresses the expansion of conventional T cells in a contact-dependent manner. After activation, CD4+CD25+ T cells express CTLA-4 on the surface detectable for several weeks. These cells show a G1/G0 cell cycle arrest and no production of interleukin (IL)-2, IL-4, or interferon (IFN)-γ on either protein or mRNA levels. The anergic state of CD4+CD25+ T cells is not reversible by the addition of anti-CD28, anti–CTLA-4, anti–transforming growth factor β, or anti–IL-10 antibody. However, the refractory state of CD4+CD25+ T cells was partially reversible by the addition of IL-2 or IL-4. These data demonstrate that human blood contains a resident T cell population with potent regulatory properties. PMID:11390435

Preparation and bioevaluation of {sup 177}Lu-labelled anti-CD44 for radioimmunotherapy of colon cancer

Energy Technology Data Exchange (ETDEWEB)

Lee, So Young; Hong, Young Don; Jung, Sung Hee; Choi, Sun Ju [Radioisotope Research Division, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2015-12-15

CD44 is a particular adhesion molecule and facilitates both cell-cell and cell-matrix interactions. In particular, splice variants of CD44 are particularly overexpressed in a large number of malignancies and carcinomas. In this study, the {sup 177}Lu-labelled CD44 targeting antibody was prepared and bioevaluated in vitro and in vivo. Anti-CD44 was immunoconjugated with the equivalent molar ratio of cysteine-based dtPA-ncS and radioimmunoconjugated with {sup 177}Lu at room temperature within 15 minutes. the stability was tested in human serum. An in vitro study was carried out in Ht-29 human colon cancer cell lines. For the biodistribution study {sup 177}Lu-labelled anti-CD44 was injected in xenograft mice. Anti-CD44 was immunoconjugated with cysteinebased dtPA-ncS and purified by a centricon filter system having a molecular cut-off of 50 kda. radioimmunoconjugation with {sup 177}Lu was reacted for 15 min at room temperature. the radiolabeling yield was >99%, and it was stable in human serum without any fragmentation or degradation. The radioimmunoconjugate showed a high binding affinity on HT-29 colon cancer cell surfaces. In a biodistribution study, the tumor-to-blood ratio of the radioimmunoconjugate was 43 : 1 at 1 day post injection (p.i) in human colon cancer bearing mice. the anti-CD44 monoclonal antibody for the targeting of colon cancer was effectively radioimmunoconjugated with {sup 177}Lu. the in vitro high immunoactivity of this radioimmunoconjugate was determined by a cell binding assay. In addition, the antibody's tumor targeting ability was demonstrated with very high uptake in tumors. this radioimmunoconjugate is applicable to therapy in human colon cancer with highly expressed CD44.

Changes in Reactivity In Vitro of CD4+CD25+ and CD4+CD25− T Cell Subsets in Transplant Tolerance

Science.gov (United States)

Hall, Bruce M.; Robinson, Catherine M.; Plain, Karren M.; Verma, Nirupama D.; Tran, Giang T.; Nomura, Masaru; Carter, Nicole; Boyd, Rochelle; Hodgkinson, Suzanne J.

2017-01-01

Transplant tolerance induced in adult animals is mediated by alloantigen-specific CD4+CD25+ T cells, yet in many models, proliferation of CD4+ T cells from hosts tolerant to specific-alloantigen in vitro is not impaired. To identify changes that may diagnose tolerance, changes in the patterns of proliferation of CD4+, CD4+CD25+, and CD4+CD25− T cells from DA rats tolerant to Piebald Virol Glaxo rat strain (PVG) cardiac allografts and from naïve DA rats were examined. Proliferation of CD4+ T cells from both naïve and tolerant hosts was similar to both PVG and Lewis stimulator cells. In mixed lymphocyte culture to PVG, proliferation of naïve CD4+CD25− T cells was greater than naïve CD4+ T cells. In contrast, proliferation of CD4+CD25− T cells from tolerant hosts to specific-donor PVG was not greater than CD4+ T cells, whereas their response to Lewis and self-DA was greater than CD4+ T cells. Paradoxically, CD4+CD25+ T cells from tolerant hosts did not proliferate to PVG, but did to Lewis, whereas naïve CD4+CD25+ T cells proliferate to both PVG and Lewis but not to self-DA. CD4+CD25+ T cells from tolerant, but not naïve hosts, expressed receptors for interferon (IFN)-γ and IL-5 and these cytokines promoted their proliferation to specific-alloantigen PVG but not to Lewis or self-DA. We identified several differences in the patterns of proliferation to specific-donor alloantigen between cells from tolerant and naïve hosts. Most relevant is that CD4+CD25+ T cells from tolerant hosts failed to proliferate or suppress to specific donor in the absence of either IFN-γ or IL-5. The proliferation to third-party and self of each cell population from tolerant and naïve hosts was similar and not affected by IFN-γ or IL-5. Our findings suggest CD4+CD25+ T cells that mediate transplant tolerance depend on IFN−γ or IL-5 from alloactivated Th1 and Th2 cells. PMID:28878770

Monoclonal anti-elastin antibody labelled with technetium-99m

International Nuclear Information System (INIS)

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

1999-01-01

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

Analysis of monoclonal antibodies reactive with molecules upregulated or expressed only on activated lymphocytes.

Science.gov (United States)

Davis, W C; Naessens, J; Brown, W C; Ellis, J A; Hamilton, M J; Cantor, G H; Barbosa, J I; Ferens, W; Bohach, G A

1996-08-01

Monoclonal antibodies potentially specific for antigens expressed or upregulated on activated leukocytes were selected for further analysis from the panel submitted to the third international workshop on ruminant leukocyte antigens. The kinetics of expression of these activation antigens on resting peripheral mononuclear cells (PBMC) and PBMC stimulated with concanavalin A or staphylococcal superantigen SECI for 4, 24 or 96 h were compared, as well as their appearance on various subsets of cells. For some of them, a molecular mass could be determined after immunoprecipitation from radio-labeled, lectin-stimulated cells. Based on the results from the clustering, kinetic studies and biochemical data, evidence was gathered for assigning two additional mAbs to cluster BoCD25 (IL-2 receptor) and two mAbs to cluster BoCD71 (transferrin receptor). Four mAbs recognized an early activation antigen predominantly expressed on gamma delta T cells in short-term cultures. A number of other activation antigens were further characterized.

In vitro experimental (211)At-anti-CD33 antibody therapy of leukaemia cells overcomes cellular resistance seen in vivo against gemtuzumab ozogamicin.

Science.gov (United States)

Petrich, Thorsten; Korkmaz, Zekiye; Krull, Doris; Frömke, Cornelia; Meyer, Geerd J; Knapp, Wolfram H

2010-05-01

Monoclonal anti-CD33 antibodies conjugated with toxic calicheamicin derivative (gemtuzumab ozogamicin, GO) are a novel therapy option for acute myeloid leukaemia (AML). Key prognostic factors for patients with AML are high CD33 expression on the leukaemic cells and the ability to overcome mechanisms of resistance to cytotoxic chemotherapies, including drug efflux or other mechanisms decreasing apoptosis. Alpha particle-emitting radionuclides overwhelm such anti-apoptotic mechanisms by producing numerous DNA double-stranded breaks (DSBs) accompanied by decreased DNA repair. We labelled anti-CD33 antibodies with the alpha-emitter (211)At and compared survival of leukaemic HL-60 and K-562 cells treated with the (211)At-labelled antibodies, GO or unlabelled antibodies as controls. We also measured caspase-3/7 activity, DNA fragmentation and necrosis in HL-60 cells after treatment with the different antibodies or with free (211)At. The mean labelling ratio of (211)At-labelled antibodies was 1:1,090 +/- 364 (range: 1:738-1:1,722) in comparison to 2-3:1 for GO. Tumour cell binding of (211)At-anti-CD33 was high in the presence of abundant CD33 expression and could be specifically blocked by unlabelled anti-CD33. (211)At-anti-CD33 decreased survival significantly more than did GO at comparable dilution (1:1,000). No significant differences in induction of apoptosis or necrosis or DNA DSB or in decreased survival were observed after (211)At-anti-CD33 (1:1,090) versus GO (1:1) treatment. Our results suggest that (211)At is a promising, highly cytotoxic radioimmunotherapy in CD33-positive leukaemia and kills tumour cells more efficiently than does calicheamicin-conjugated antibody. Labelling techniques leading to higher chemical yield and specific activities must be developed to increase (211)At-anti-CD33 therapeutic effects.

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

Science.gov (United States)

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

1992-02-01

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

Anomalous expression of Thy1 (CD90) in B-cell lymphoma cells and proliferation inhibition by anti-Thy1 antibody treatment

Energy Technology Data Exchange (ETDEWEB)

Ishiura, Yoshihito [Department of Biochemistry, Kochi University Medical School, Kohasu, Okocho, Nankoku, Kochi 783-8505 (Japan); CREST, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012 (Japan); Kotani, Norihiro, E-mail: kotani@kochi-u.ac.jp [CREST, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012 (Japan); Kochi System Glycobiology Center, Kochi University Medical School, Kohasu, Okocho, Nankoku, Kochi 783-8505 (Japan); Yamashita, Ryusuke [Department of Biochemistry, Kochi University Medical School, Kohasu, Okocho, Nankoku, Kochi 783-8505 (Japan); CREST, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012 (Japan); Yamamoto, Harumi [Laboratory of Membrane Biochemistry and Biophysics, Graduate School of Biostudies, Kyoto University, Yoshida Shimo-Adachi, Sakyo, Kyoto 606-8501 (Japan); Kozutsumi, Yasunori [CREST, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012 (Japan); Laboratory of Membrane Biochemistry and Biophysics, Graduate School of Biostudies, Kyoto University, Yoshida Shimo-Adachi, Sakyo, Kyoto 606-8501 (Japan); Honke, Koichi [Department of Biochemistry, Kochi University Medical School, Kohasu, Okocho, Nankoku, Kochi 783-8505 (Japan); CREST, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012 (Japan); Kochi System Glycobiology Center, Kochi University Medical School, Kohasu, Okocho, Nankoku, Kochi 783-8505 (Japan)

2010-05-28

The anti-CD20 monoclonal antibody (Ab) rituximab is accepted to be an effective therapeutic Ab for malignant B-cell lymphoma; however, discovery of other cell surface antigens is required for the option of antibody medicine. Considering that many tumor-associated antigens are glycans, we have searched glycoconjugates for the candidate antigens that therapeutic Abs target. To this end, we first focused on the difference in the glycogenes expression in terms of Epstein-Barr virus (EBV) infection of a Burkitt's lymphoma cell line, Akata. Using DNA array, flow cytometry and Western blotting, we found that Thy1 was highly expressed in EBV-positive Akata cells. Subsequently, Thy1 was found to be expressed in other B-cell lymphoma cell lines: BJAB, MutuI, and MutuIII, irrespective of EBV infection. Treatment of these cells with an anti-Thy1 monoclonal antibody inhibited proliferation more strongly than the therapeutic Ab rituximab. The B-cell lymphoma cell lines were classified based on the extent of the proliferation inhibition, which was not correlated with the expression level of Thy1. It is suggested that stable residence of receptor tyrosine kinases in lipid rafts sustains cell growth in B-cell lymphoma cells.

Preparation of the radiopharmaceutical {sup 131}I-Anti-CD20 for the treatment of lymphomas; Preparacion del radiofarmaco {sup 131}I-Anti-CD20 para el tratamiento de linfomas

Energy Technology Data Exchange (ETDEWEB)

Pantoja H, I.E

2004-07-01

At the present time they are considered to the lymphomas like a problem of first magnitude since has happened it is necessary to be the fifth cancer cause in the world. Different treatments focused to the lymphoma like the chemotherapy and the radiotherapy, have been employees to counteract the No-Hodgkin lymphoma, without these they don't exclude the healthy tissue of the toxicity. It is for it that is taking a new direction with the employment of the directed radioimmunotherapy since this it allows to kill wicked cells selectively with radiation dose joined to the apoptosis and cytotoxicity induced by the own one bio molecule. The radioimmunotherapy with radiolabelled antibodies directed to the surface antigen CD20 represents a new modality for the treatment of No-Hodgkin lymphoma and potentially other illnesses. In this work the parameters of optimization are presented for the preparation, control of quality and evaluation of the stability in vitro and in vivo of the monoclonal antibody anti-CD20 labelled with {sup 131} I for the treatment of No-Hodgkin lymphoma. The anti-CD20 labelled by the chloramine-T method with high radiochemical purity (>98%), it is stable in solution for but of a half life of the radionuclide (8.04 days) The {sup 131} I-anti-CD20 doesn't present dehalogenation in vitro (human serum) during 24 h of incubation at 37 C. According to the tests carried out to establish the immunoreactivity, a percentage of union to cells was obtained (B lymphocytes) bigger to 30%. The biodistribution in mice balb/c one hour after their administration, it shows that there is not high reception in mucous neither kidneys, what indicates that the complex is stable in vivo. In conclusion, the radiopharmaceutical {sup 131} I-anti-CD20 was obtained in sterile injectable solution and free of pyrogens with a radiochemical purity bigger to 98% and a specific activity of 296 MBq. The radiolabelled molecule maintains its biological recognition for the receiving

HPMA copolymer conjugates with reduced anti-CD20 antibody for cell-specific drug targeting. I. Synthesis and in vitro evaluation of binding efficacy and cytostatic activity

Czech Academy of Sciences Publication Activity Database

Etrych, Tomáš; Strohalm, Jiří; Kovář, Lubomír; Kabešová, Martina; Říhová, Blanka; Ulbrich, Karel

2009-01-01

Roč. 140, č. 1 (2009), s. 18-26 ISSN 0168-3659 R&D Projects: GA MŠk 1M0505; GA AV ČR IAAX00500803 Institutional research plan: CEZ:AV0Z40500505; CEZ:AV0Z50200510 Keywords : HPMA copolymers * drug delivery systems * doxorubicin * monoclonal anti-CD20 antibody * drug targeting Subject RIV: CD - Macromolecular Chemistry Impact factor: 5.949, year: 2009

Dosimetry and microdosimetry of 188 Re-anti-CD20 and 131 I-anti-CD20 for the treatment of No Hodgkin lymphomas

International Nuclear Information System (INIS)

Torres G, E.

2007-01-01

The purpose of this investigation was to prepare 131 I-anti-CD20 and 188 Re-anti-CD20 and to estimate the radiation absorbed dose at macro- and micro- level during a NHL treatment. The work was divided in 4 general objectives: 1) preparation of 131 I-anti-CD20 and 188 Re-anti-CD20, 2) application in patients to obtain biokinetic parameters and estimate the organ absorbed doses 3) estimation of the cellular dosimetry using the MIRD methodology and the MCNP4C2 code and 4) estimation of the cellular microdosimetry using the NOREC code. 188 Re-anti-CD20 was prepared by a direct labelling method using sodium tartrate as a weak ligand. To evaluate the biological recognition a comparative study of the in vitro binding of 188 Re-anti-CD20, 125 I-anti-CD20 (positive control) and 188 Re-anti-CEA (negative control) to normal B Iymphocytes was performed. Biodistribution studies in normal mice were accomplished to assess the in vivo Re-anti-CD20 complex stability. The binding of ' Re-anti-CD20 to cells was in the same range as '251-anti-CD20 (>80%) considered as the positive control. 188 Re-anti-CD20 and '3'1-anti-CD20 prepared were administered in patients diagnosed with B cell NHL at the Centro Medico Siglo XXI (IMSS). The protocol was approved by the hospital's Medical Ethics Committee. AJI patients signed a consent form after receiving detailed information on the aims of the study. N data were the input for the OLINDA/EXM software to calculate the radiation absorbed dose to organs and whole body. Dosimetric studies indicate that after administration of 6.4 GBq and 4.87 to 8.75 GBq of '3'1-anti-CD20 and 188 Re-anti-CD20 respectively, the absorbed dose to total body would be 0.75 Gy which corresponds to the recommended dose for NHL therapies. The calculated organ absorbed doses indicate that 188 Re-anti-CD20 may be used in radioimmunotherapy without the risk of toxicity to red marrow or healthy organs. The absorbed dose (D) into cellular nucleus was calculated by two

Dosimetry and microdosimetry of {sup 188} Re-anti-CD20 and {sup 131} I-anti-CD20 for the treatment of No Hodgkin lymphomas; Dosimetria y microdosimetria del {sup 188} Re-anti-CD20 y {sup 131} I-anti-CD20 para el tratamiento de linfomas No Hodgkin

Energy Technology Data Exchange (ETDEWEB)

Torres G, E

2007-07-01

The purpose of this investigation was to prepare {sup 131}I-anti-CD20 and {sup 188}Re-anti-CD20 and to estimate the radiation absorbed dose at macro- and micro- level during a NHL treatment. The work was divided in 4 general objectives: 1) preparation of {sup 131}I-anti-CD20 and {sup 188}Re-anti-CD20, 2) application in patients to obtain biokinetic parameters and estimate the organ absorbed doses 3) estimation of the cellular dosimetry using the MIRD methodology and the MCNP4C2 code and 4) estimation of the cellular microdosimetry using the NOREC code. {sup 188}Re-anti-CD20 was prepared by a direct labelling method using sodium tartrate as a weak ligand. To evaluate the biological recognition a comparative study of the in vitro binding of {sup 188}Re-anti-CD20, {sup 125}I-anti-CD20 (positive control) and {sup 188}Re-anti-CEA (negative control) to normal B Iymphocytes was performed. Biodistribution studies in normal mice were accomplished to assess the in vivo Re-anti-CD20 complex stability. The binding of ' Re-anti-CD20 to cells was in the same range as '251-anti-CD20 (>80%) considered as the positive control. {sup 188}Re-anti-CD20 and '3'1-anti-CD20 prepared were administered in patients diagnosed with B cell NHL at the Centro Medico Siglo XXI (IMSS). The protocol was approved by the hospital's Medical Ethics Committee. AJI patients signed a consent form after receiving detailed information on the aims of the study. N data were the input for the OLINDA/EXM software to calculate the radiation absorbed dose to organs and whole body. Dosimetric studies indicate that after administration of 6.4 GBq and 4.87 to 8.75 GBq of '3'1-anti-CD20 and {sup 188}Re-anti-CD20 respectively, the absorbed dose to total body would be 0.75 Gy which corresponds to the recommended dose for NHL therapies. The calculated organ absorbed doses indicate that {sup 188}Re-anti-CD20 may be used in radioimmunotherapy without the risk of toxicity to red marrow or

Dosimetry and microdosimetry of {sup 188} Re-anti-CD20 and {sup 131} I-anti-CD20 for the treatment of No Hodgkin lymphomas; Dosimetria y microdosimetria del {sup 188} Re-anti-CD20 y {sup 131} I-anti-CD20 para el tratamiento de linfomas No Hodgkin

Energy Technology Data Exchange (ETDEWEB)

Torres G, E

2007-07-01

The purpose of this investigation was to prepare {sup 131}I-anti-CD20 and {sup 188}Re-anti-CD20 and to estimate the radiation absorbed dose at macro- and micro- level during a NHL treatment. The work was divided in 4 general objectives: 1) preparation of {sup 131}I-anti-CD20 and {sup 188}Re-anti-CD20, 2) application in patients to obtain biokinetic parameters and estimate the organ absorbed doses 3) estimation of the cellular dosimetry using the MIRD methodology and the MCNP4C2 code and 4) estimation of the cellular microdosimetry using the NOREC code. {sup 188}Re-anti-CD20 was prepared by a direct labelling method using sodium tartrate as a weak ligand. To evaluate the biological recognition a comparative study of the in vitro binding of {sup 188}Re-anti-CD20, {sup 125}I-anti-CD20 (positive control) and {sup 188}Re-anti-CEA (negative control) to normal B Iymphocytes was performed. Biodistribution studies in normal mice were accomplished to assess the in vivo Re-anti-CD20 complex stability. The binding of ' Re-anti-CD20 to cells was in the same range as '251-anti-CD20 (>80%) considered as the positive control. {sup 188}Re-anti-CD20 and '3'1-anti-CD20 prepared were administered in patients diagnosed with B cell NHL at the Centro Medico Siglo XXI (IMSS). The protocol was approved by the hospital's Medical Ethics Committee. AJI patients signed a consent form after receiving detailed information on the aims of the study. N data were the input for the OLINDA/EXM software to calculate the radiation absorbed dose to organs and whole body. Dosimetric studies indicate that after administration of 6.4 GBq and 4.87 to 8.75 GBq of '3'1-anti-CD20 and {sup 188}Re-anti-CD20 respectively, the absorbed dose to total body would be 0.75 Gy which corresponds to the recommended dose for NHL therapies. The calculated organ absorbed doses indicate that {sup 188}Re-anti-CD20 may be used in radioimmunotherapy without the risk of toxicity to red marrow or healthy organs. The absorbed dose

In vitro experimental {sup 211}At-anti-CD33 antibody therapy of leukaemia cells overcomes cellular resistance seen in vivo against gemtuzumab ozogamicin

Energy Technology Data Exchange (ETDEWEB)

Petrich, Thorsten; Korkmaz, Zekiye; Krull, Doris; Meyer, Geerd J.; Knapp, Wolfram H. [Hanover University School of Medicine, Department of Nuclear Medicine, Hanover (Germany); Froemke, Cornelia [Hanover University School of Medicine, Department of Biometry, Hanover (Germany)

2010-05-15

Monoclonal anti-CD33 antibodies conjugated with toxic calicheamicin derivative (gemtuzumab ozogamicin, GO) are a novel therapy option for acute myeloid leukaemia (AML). Key prognostic factors for patients with AML are high CD33 expression on the leukaemic cells and the ability to overcome mechanisms of resistance to cytotoxic chemotherapies, including drug efflux or other mechanisms decreasing apoptosis. Alpha particle-emitting radionuclides overwhelm such anti-apoptotic mechanisms by producing numerous DNA double-stranded breaks (DSBs) accompanied by decreased DNA repair. We labelled anti-CD33 antibodies with the alpha-emitter {sup 211}At and compared survival of leukaemic HL-60 and K-562 cells treated with the {sup 211}At-labelled antibodies, GO or unlabelled antibodies as controls. We also measured caspase-3/7 activity, DNA fragmentation and necrosis in HL-60 cells after treatment with the different antibodies or with free {sup 211}At. The mean labelling ratio of {sup 211}At-labelled antibodies was 1:1,090 {+-} 364 (range: 1:738-1:1,722) in comparison to 2-3:1 for GO. Tumour cell binding of {sup 211}At-anti-CD33 was high in the presence of abundant CD33 expression and could be specifically blocked by unlabelled anti-CD33. {sup 211}At-anti-CD33 decreased survival significantly more than did GO at comparable dilution (1:1,000). No significant differences in induction of apoptosis or necrosis or DNA DSB or in decreased survival were observed after {sup 211}At-anti-CD33 (1:1,090) versus GO (1:1) treatment. Our results suggest that {sup 211}At is a promising, highly cytotoxic radioimmunotherapy in CD33-positive leukaemia and kills tumour cells more efficiently than does calicheamicin-conjugated antibody. Labelling techniques leading to higher chemical yield and specific activities must be developed to increase {sup 211}At-anti-CD33 therapeutic effects. (orig.)

Preparation of the radiopharmaceutical 131I-Anti-CD20 for the treatment of lymphomas

International Nuclear Information System (INIS)

Pantoja H, I.E.

2004-01-01

At the present time they are considered to the lymphomas like a problem of first magnitude since has happened it is necessary to be the fifth cancer cause in the world. Different treatments focused to the lymphoma like the chemotherapy and the radiotherapy, have been employees to counteract the No-Hodgkin lymphoma, without these they don't exclude the healthy tissue of the toxicity. It is for it that is taking a new direction with the employment of the directed radioimmunotherapy since this it allows to kill wicked cells selectively with radiation dose joined to the apoptosis and cytotoxicity induced by the own one bio molecule. The radioimmunotherapy with radiolabelled antibodies directed to the surface antigen CD20 represents a new modality for the treatment of No-Hodgkin lymphoma and potentially other illnesses. In this work the parameters of optimization are presented for the preparation, control of quality and evaluation of the stability in vitro and in vivo of the monoclonal antibody anti-CD20 labelled with 131 I for the treatment of No-Hodgkin lymphoma. The anti-CD20 labelled by the chloramine-T method with high radiochemical purity (>98%), it is stable in solution for but of a half life of the radionuclide (8.04 days) The 131 I-anti-CD20 doesn't present dehalogenation in vitro (human serum) during 24 h of incubation at 37 C. According to the tests carried out to establish the immunoreactivity, a percentage of union to cells was obtained (B lymphocytes) bigger to 30%. The biodistribution in mice balb/c one hour after their administration, it shows that there is not high reception in mucous neither kidneys, what indicates that the complex is stable in vivo. In conclusion, the radiopharmaceutical 131 I-anti-CD20 was obtained in sterile injectable solution and free of pyrogens with a radiochemical purity bigger to 98% and a specific activity of 296 MBq. The radiolabelled molecule maintains its biological recognition for the receiving CD20 highly expressed in

First-in-human phase 1 of YS110, a monoclonal antibody directed against CD26 in advanced CD26-expressing cancers.

Science.gov (United States)

Angevin, Eric; Isambert, Nicolas; Trillet-Lenoir, Véronique; You, Benoit; Alexandre, Jérôme; Zalcman, Gérard; Vielh, Philippe; Farace, Françoise; Valleix, Fanny; Podoll, Thomas; Kuramochi, Yu; Miyashita, Itaru; Hosono, Osamu; Dang, Nam H; Ohnuma, Kei; Yamada, Taketo; Kaneko, Yutaro; Morimoto, Chikao

2017-04-25

YS110 is a humanised IgG1 monoclonal antibody with high affinity to the CD26 antigen. YS110 demonstrated preclinical anti-tumour effects without significant side effects. This FIH study was designed to determine the maximal tolerated dose (MTD) and recommended phase 2 dose (RP2D) to assess the tolerance, pharmacokinetics (PK) and pharmacodynamics profiles of YS110 and preliminary efficacy. YS110 were initially administered intravenously once every 2 weeks (Q2W) for three doses and then, based on PK data, once every week (Q1W) for five doses in patients with CD26-expressing solid tumours. Thirty-three patients (22 mesothelioma) received a median of 3 (range 1-30) YS110 infusions across six dose levels (0.1-6 mg kg -1 ). MTD was not reached and two dose-limiting toxicities (infusion hypersensitivity reactions) led to the institution of a systemic premedication. Low-grade asthenia (30.3%), hypersensitivity (27.3%), nausea (15.2%), flushing (15.2%), chills (12.1%) and pyrexia (12.1%) were reported as ADRs. Pharmacokinetic parameters (AUC and C max ) increased in proportion with the dose. sCD26/DPPIV assays indicated CD26 modulation. Prolonged stable diseases were observed in 13 out of 26 evaluable patients. YS110 is well tolerated up to 6 mg kg -1 Q1W, which has been defined as the RP2D, with encouraging prolonged disease stabilisations observed in a number of patients with advanced/refractory mesothelioma.

Adenoviral vaccination combined with CD40 stimulation and CTLA-4 blockage can lead to complete tumor regression in a murine melanoma model

DEFF Research Database (Denmark)

Sørensen, Maria Rathmann; Holst, Peter J; Steffensen, Maria Abildgaard

2010-01-01

that the delay in tumor growth can be converted to complete regression and long-term survival in 30-40% of the mice by a booster vaccination plus combinational treatment with agonistic anti-CD40 monoclonal antibodies (mAb) and anti-CTLA-4 mAb. Regarding the mechanism underlying the improved clinical effect......, analysis of the tumor-specific response revealed a significantly prolonged tumor-specific CD8 T cell response in spleens of the mice receiving the combinational treatment compared with mice receiving either treatment individually. Matching this, CD8 T cell depletion completely prevented tumor control...

Tetravalent anti-CD20/CD3 bispecific antibody for the treatment of B cell lymphoma

Energy Technology Data Exchange (ETDEWEB)

Lu, Chia-Yen; Chen, Gregory J.; Tai, Pei-Han; Yang, Yu-Chen [Institute of Biologics, Development Center for Biotechnology, New Taipei City, Taiwan (China); Hsu, Yu-Shen, E-mail: yshsu@advagene.com.tw [Laboratory of Biopharmaceutical Research, Advagene Biopharma, Taipei, Taiwan (China); Chang, Mingi, E-mail: mingi.chang@advagene.com.tw [Laboratory of Biopharmaceutical Research, Advagene Biopharma, Taipei, Taiwan (China); Hsu, Chuan-Lung, E-mail: fabio@dcb.org.tw [Institute of Biologics, Development Center for Biotechnology, New Taipei City, Taiwan (China)

2016-05-13

Bispecific antibodies (bsAbs) are second generation antibodies for therapeutic application in immunotherapy. One of the major strategies of the bsAb platform is the recruitment of immune effector T cells by incorporating an anti-CD3 domain. A bispecific T-cell engager (BiTE), with one end having an affinity for CD3 and the other end with affinity for CD19, has been approved in the US and Europe for the treatment of acute lymphoblastic leukemia. However, due to their small size and lack of Fc region, these single-chain variable fragment (scFv) bsAbs have short half-lives in vivo. Additionally, poor solubility, structural instability, and low production yields have also become major challenges in the bulk production process. To overcome these challenges, we have engineered a tetravalent bsAb with bivalent binding specificity for the CD20 and CD3 antigen in an immunoglobulin G (IgG) format. The fusion of the anti-CD3 scFvs to the CD20 antibody via a linker-hinge domain (LHD) results in improved antibody stabilization and properties. Here we demonstrate this antibody's highly efficient cancer cell elimination in a dose-dependent manner in a CD20-expressing B lymphoblastoid cell line in vitro. Our data suggest the potential clinical application of this bsAb for the treatment of CD20-expressing B cell malignancies. - Highlights: • A bispecific antibody (bsAb) can increase immunotherapeutic efficacy. • A tetravalent bsAb with binding specificity for the CD20 and CD3 antigens is proposed. • A linker-hinge domain (LHD) within the bsAb results in improved antibody properties.

Purification of a polyclonal antibody against CD147 for ELISA using antigen-immunoaffinity chromatography

Science.gov (United States)

Liu, Shuangshuang; Li, Shasha; Zhang, Yang; Wang, Ye; Zhu, Yumeng; Wang, Bin; Chen, Zhi-Nan

2017-01-01

The immunoglobulin superfamily member CD147 is a widely expressed glycoprotein that occurs in both a membrane-spanning and soluble form. Sandwich ELISA is a powerful tool for analyzing soluble antigens. The aim of the present study was to obtain a highly specific polyclonal antibody against human CD147 that can be used for sandwich ELISA analysis. Expression of recombinant CD147 by a eukaryotic expression system was used to immunize rabbits to obtain antiserum. A highly specific polyclonal antibody that was able to detect soluble CD147 in sandwich ELISA was obtained by antigen-immunoaffinity chromatography purification. The purity of rabbit anti-CD147 polyclonal antibodies was ~99%, and ELISA analysis was able to determine the titer of the rabbit anti-CD147 polyclonal antibodies at 1:512,000. The lowest concentration of the standard CD147 antigen that the sandwich ELISA was able to detect was 31.25 pg/ml. The sandwich ELISA system was composed of anti-hepatoma HAb18 monoclonal antibodies and purified rabbit anti-CD147 polyclonal antibodies. The present study demonstrated that antigen-immunoaffinity chromatography may be a good technique for the purification of polyclonal antibodies, which may be used to detect antigen in sandwich ELISAs. PMID:28487989

Modulation of phenotype and function of human CD4+CD25+ T regulatory lymphocytes mediated by cAMP elevating agents

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Antonella Riccomi

2016-09-01

Full Text Available We have shown that Cholera Toxin (CT and other cyclic AMP (cAMP elevating agents induce up-regulation of the inhibitory molecule CTLA-4 in human resting CD4+ T lymphocytes, which following the treatment acquired suppressive functions. In this study, we evaluated the effect of cAMP elevating agents on human CD4+CD25+ T cells, which include the T regulatory (Treg cells that play a pivotal role in the maintenance of immunological tolerance. We found that cAMP elevating agents induce up-regulation of CTLA-4 in CD4+CD25- and further enhance its expression in CD4+CD25+ T cells. We observed an increase of two isoforms of mRNA coding for the membrane and the soluble CTLA-4 molecules, suggesting that the regulation of CTLA-4 expression by cAMP is at the transcriptional level. In addition, we found that the increase of cAMP in CD4+CD25+ T cells converts the CD4+CD25+Foxp3- T cells in CD4+CD25+Foxp3+ T cells, whereas the increase of cAMP in CD4+CD25- T cells did not up-regulate Foxp3 in the absence of activation stimuli. To investigate the function of these cells, we performed an in vitro suppression assay by culturing CD4+CD25+ T cells untreated or pre-treated with CT with anti-CD3 mAbs-stimulated autologous PBMC. We found that CT enhances the inhibitory function of CD4+CD25+ T cells, CD4+ and CD8+ T cell proliferation and IFNγ production are strongly inhibited by CD4+CD25+ T cells pre-treated with cAMP elevating agents. Furthermore, we found that CD4+CD25+ T lymphocytes pre-treated with cAMP elevating agents induce the up-regulation of CD80 and CD86 co-stimulatory molecules on immature dendritic cells (DCs in the absence of antigenic stimulation, however without leading to full DC maturation. These data show that the increase of intracellular cAMP modulates the phenotype and function of human CD4+CD25+ T cells.

Anti-interleukin-17 monoclonal antibody ixekizumab in chronic plaque psoriasis

DEFF Research Database (Denmark)

Leonardi, Craig; Matheson, Robert; Zachariae, Claus

2012-01-01

Type 17 helper T cells have been suggested to play a pathological role in psoriasis. They secrete several proinflammatory cytokines, including interleukin-17A (also known as interleukin-17). We evaluated the safety and efficacy of ixekizumab (LY2439821), a humanized anti-interleukin-17 monoclonal...... antibody, for psoriasis treatment....

Mouse CD23 regulates monocyte activation through an interaction with the adhesion molecule CD11b/CD18.

Science.gov (United States)

Lecoanet-Henchoz, S; Plater-Zyberk, C; Graber, P; Gretener, D; Aubry, J P; Conrad, D H; Bonnefoy, J Y

1997-09-01

CD23 is expressed on a variety of hemopoietic cells. Recently, we have reported that blocking CD23 interactions in a murine model of arthritis resulted in a marked improvement of disease severity. Here, we demonstrate that CD11b, the alpha chain of the beta 2 integrin adhesion molecule complex CD11b/CD18 expressed on monocytes interacts with CD23. Using a recombinant fusion protein (ZZ-CD23), murine CD23 was shown to bind to peritoneal macrophages and peripheral blood cells isolated from mice as well as the murine macrophage cell line, RAW. The interactions between mouse ZZ-CD23 and CD11b/CD18-expressing cells were significantly inhibited by anti-CD11b monoclonal antibodies. A functional consequence was then demonstrated by inducing an up-regulation of interleukin-6 (IL-6) production following ZZ-CD23 incubation with monocytes. The addition of Fab fragments generated from the monoclonal antibody CD11b impaired this cytokine production by 50%. Interestingly, a positive autocrine loop was identified as IL-6 was shown to increase CD23 binding to macrophages. These results demonstrate that similar to findings using human cells, murine CD23 binds to the surface adhesion molecule, CD11b, and these interactions regulate biological activities of murine myeloid cells.

Anti-CD20 Immunoglobulin G Radiolabeling with a 99mTc-Tricarbonyl Core: In Vitro and In Vivo Evaluations.

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Hélène Carpenet

Full Text Available In recent years, the diagnostic and therapeutic uses of radioisotopes have shown significant progress. Immunoglobulin (Ig appears to be a promising tracer, particularly due to its ability to target selected antigens. The main objective of this study is to optimize and assess an Ig radiolabeling method with Technetium 99m (99mTc, an attractive radioelement used widely for diagnostic imaging. Monoclonal anti-CD20 IgG was retained to study in vitro and in vivo radiolabeling impact. After IgG derivatization with 2-iminothiolane, IgG-SH was radiolabeled by an indirect method, using a 99mTc-tricarbonyl core. Radiolabeling stability was evaluated over 24h by thin-layer chromatography. IgG integrity was checked by sodium dodecyl sulfate-polyacrylamide gel electrophoresis coupled with Western blot and autoradiography. The radiolabeled Ig's immunoaffinity was assessed in vitro by a radioimmunoassay method and binding experiments with cells (EL4-hCD20 and EL4-WT. Biodistribution studies were performed in normal BALB/c mice. Tumor uptake was assessed in mice bearing EL4-hCD20 and EL4-WT subcutaneous xenografts. With optimized method, high radiolabeling yields were obtained (95.9 ± 3.5%. 99mTc-IgG-SH was stable in phosphate-buffered saline (4°C and 25°C and in serum (37°C, even if important sensitivity to transchelation was observed. IgG was not degraded by derivatization and radiolabeling, as shown by Western blot and autoradiography results. 99mTc-anti-CD20 IgG-SH immunoaffinity was estimated with Kd = 35 nM by both methods. In vivo biodistribution studies for 48h showed significant accumulation of radioactivity in plasma, liver, spleen, lungs and kidneys. Planar scintigraphy of mice bearing tumors showed a significant uptake of 99mTc-anti-CD20 IgG-SH in CD20+ tumor versus CD20- tumor. Radiolabeling of derivatized IgG with 99mTc-tricarbonyl was effective, stable and required few antibody amounts. This attractive radiolabeling method is "antibody safe

Molecular imaging of rheumatoid arthritis by radiolabelled monoclonal antibodies: new imaging strategies to guide molecular therapies

Energy Technology Data Exchange (ETDEWEB)

Malviya, G.; Dierckx, R.A. [Department of Nuclear Medicine and Molecular Imaging, University Medical Centre Groningen, University of Groningen (Netherlands); Conti, F. [Rheumatology Unit, I Faculty of Medicine and Surgery, Sapienza University of Rome (Italy); Chianelli, M. [Department of Nuclear Medicine and Molecular Imaging, University Medical Centre Groningen, University of Groningen (Netherlands); Unit of Nuclear Medicine, Regina apostolorum Hospital, Albano, Rome (Italy); Scopinaro, F. [Nuclear Medicine Department, Sapienza University of Rome, St. Andrea Hospital, Rome (Italy); Signore, A. [Department of Nuclear Medicine and Molecular Imaging, University Medical Centre Groningen, University of Groningen (Netherlands); Nuclear Medicine Department, Sapienza University of Rome, St. Andrea Hospital, Rome (Italy)

2010-02-15

The closing of the last century opened a wide variety of approaches for inflammation imaging and treatment of patients with rheumatoid arthritis (RA). The introduction of biological therapies for the management of RA started a revolution in the therapeutic armamentarium with the development of several novel monoclonal antibodies (mAbs), which can be murine, chimeric, humanised and fully human antibodies. Monoclonal antibodies specifically bind to their target, which could be adhesion molecules, activation markers, antigens or receptors, to interfere with specific inflammation pathways at the molecular level, leading to immune-modulation of the underlying pathogenic process. These new generation of mAbs can also be radiolabelled by using direct or indirect method, with a variety of nuclides, depending upon the specific diagnostic application. For studying rheumatoid arthritis patients, several monoclonal antibodies and their fragments, including anti-TNF-{alpha}, anti-CD20, anti-CD3, anti-CD4 and anti-E-selectin antibody, have been radiolabelled mainly with {sup 99m}Tc or {sup 111}In. Scintigraphy with these radiolabelled antibodies may offer an exciting possibility for the study of RA patients and holds two types of information: (1) it allows better staging of the disease and diagnosis of the state of activity by early detection of inflamed joints that might be difficult to assess; (2) it might provide a possibility to perform 'evidence-based biological therapy' of arthritis with a view to assessing whether an antibody will localise in an inflamed joint before using the same unlabelled antibody therapeutically. This might prove particularly important for the selection of patients to be treated since biological therapies can be associated with severe side-effects and are considerably expensive. This article reviews the use of radiolabelled mAbs in the study of RA with particular emphasis on the use of different radiolabelled monoclonal antibodies for

Molecular imaging of rheumatoid arthritis by radiolabelled monoclonal antibodies: new imaging strategies to guide molecular therapies

International Nuclear Information System (INIS)

Malviya, G.; Dierckx, R.A.; Conti, F.; Chianelli, M.; Scopinaro, F.; Signore, A.

2010-01-01

The closing of the last century opened a wide variety of approaches for inflammation imaging and treatment of patients with rheumatoid arthritis (RA). The introduction of biological therapies for the management of RA started a revolution in the therapeutic armamentarium with the development of several novel monoclonal antibodies (mAbs), which can be murine, chimeric, humanised and fully human antibodies. Monoclonal antibodies specifically bind to their target, which could be adhesion molecules, activation markers, antigens or receptors, to interfere with specific inflammation pathways at the molecular level, leading to immune-modulation of the underlying pathogenic process. These new generation of mAbs can also be radiolabelled by using direct or indirect method, with a variety of nuclides, depending upon the specific diagnostic application. For studying rheumatoid arthritis patients, several monoclonal antibodies and their fragments, including anti-TNF-α, anti-CD20, anti-CD3, anti-CD4 and anti-E-selectin antibody, have been radiolabelled mainly with 99m Tc or 111 In. Scintigraphy with these radiolabelled antibodies may offer an exciting possibility for the study of RA patients and holds two types of information: (1) it allows better staging of the disease and diagnosis of the state of activity by early detection of inflamed joints that might be difficult to assess; (2) it might provide a possibility to perform 'evidence-based biological therapy' of arthritis with a view to assessing whether an antibody will localise in an inflamed joint before using the same unlabelled antibody therapeutically. This might prove particularly important for the selection of patients to be treated since biological therapies can be associated with severe side-effects and are considerably expensive. This article reviews the use of radiolabelled mAbs in the study of RA with particular emphasis on the use of different radiolabelled monoclonal antibodies for therapy decision-making and

MHC class II ligation induces CD58 (LFA-3)-mediated adhesion in human T cells

DEFF Research Database (Denmark)

Nielsen, M; Gerwien, J; Geisler, C

1998-01-01

ligation induces homotypic adhesion in both beta2-integrin-positive and negative, CD4-positive T cell lines. Anti-CD18 monoclonal antibody (mAb) weakly inhibited the adhesion response in beta2-integrin-positive T cells and had no effect on beta2-integrin-negative T cells. In contrast, an anti-CD58 (LFA-3...

Enzyme-linked immunosorbent assay for total sennosides using anti-sennside A and anti-sennoside B monoclonal antibodies.

Science.gov (United States)

Morinaga, Osamu; Uto, Takuhiro; Sakamoto, Seiichi; Tanaka, Hiroyuki; Shoyama, Yukihiro

2009-01-01

Total sennosides concentration is a very important factor when rhubarb and senna will be used as crude drugs. However, one-step analytical technique for total sennosides has not been reported except HPLC. An enzyme-linked immunosorbent assay (ELISA) for total sennosides concentration by using the combination of anti-sennoside A (SA) and anti-sennoside B (SB) monoclonal antibodies (MAbs) in a single assay has been investigated. Total sennosides concentration in rhubarb and senna samples determined by newly developed assay system showed good agreement with those analyzed by ELISA using anti-SA MAb and anti-SB MAb, respectively.

Prevention of renal allograft rejection in primates by blocking the B7/CD28 pathway

NARCIS (Netherlands)

Ossevoort, MA; Ringers, J; Kuhn, EM; Boon, L; Lorre, K; van den Hout, Y; Bruijn, JA; de Boer, H; Jonker, Margreet; de Waele, P

1999-01-01

Background. There is accumulating evidence that blockade of the costimulatory pathways offers a valid approach for immune suppression after solid organ transplantation. In this study, the efficacy of anti-CD86 and anti-CD86 monoclonal antibodies (mAbs) in combination with cyclosporine (CsA) to

Short-term exercise training reduces anti-inflammatory action of interleukin-10 in adults with obesity.

Science.gov (United States)

Barry, Julianne C; Simtchouk, Svetlana; Durrer, Cody; Jung, Mary E; Mui, Alice L; Little, Jonathan P

2018-06-06

A key pathological component of obesity is chronic low-grade inflammation, which is propagated by infiltration of immune cells into tissues and overproduction of pro-inflammatory cytokines. Cytokines that possess anti-inflammatory properties, such as interleukin (IL)-10 and IL6, may also play an important role. This study was designed to determine the impact of short-term exercise on the anti-inflammatory action of IL10 and IL6. Thirty-three inactive obese adults were randomized to two weeks of high-intensity interval training (HIIT) or moderate-intensity continuous training (MICT). Fasting blood samples were collected before and after training. Lipopolysaccharide (LPS)-induced tumor necrosis factor (TNF)-α production was measured in whole blood cultures in the presence or absence of IL10 or IL6. IL10 and IL6 receptor expression were measured on circulating monocytes, neutrophils, and T cells. HIIT and MICT reduced the ability of IL10 to inhibit LPS-induced TNFα production, with a greater effect with HIIT (Group × Time and IL10 × Time interactions, p's  0.05). HIIT and MICT differentially affected IL6 function (Group × Time and IL6 × Time interactions, p's < 0.05) with evidence of reductions in the anti-inflammatory ability of IL6 with HIIT. Neither HIIT nor MICT altered levels of circulating IL10, IL6, or TNFα. The impact of short-term HIIT and MICT resulted in differential effects on anti-inflammatory cytokine function. The clinical implications remain to be determined but these novel findings indicate that measuring anti-inflammatory cytokine action could reveal important immunomodulatory effects of exercise. Copyright © 2018. Published by Elsevier Ltd.

Expresión fenotípica de las moléculas CD5 y CD6 en la leucemia linfoide crónica B-CD5+ The B-CD5+ chronic lymphoid leukemia related to the phenotype expression

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Bertha Beatriz Socarrás Ferrer

2009-04-01

Full Text Available Las moléculas CD5 y CD6 tienen función coestimuladora y muestran homología en su estructura. Se evaluó la expresión de la molécula CD6 mediante el uso del anticuerpo monoclonal anti-CD6 (T1 en el inmunofenotipaje celular de pacientes con leucemia linfoide crónica By se comparó con la expresión de la molécula CD5.Los resultados demuestranuna homología en la expresión fenotípica de ambas moléculas, CD5 y CD6, lo que asociado con que ambos receptores linfocitarios se encuentran físicamente vinculados, permite sugerir que la molécula CD6 constituye un marcador biológico de interés en la evaluación del pronóstico y la posibilidad de nuevas variantes terapéuticas en esta enfermedad.CD5 and CD6 molecules have a co-stimulant function and show homology in structure. We assessed CD6 molecule expression using anti-CD6 (T1 monoclonal antibody in the cellular immunophenotyping from patients presenting B chronic lymphoid leukemia, and it was compared to CD5 molecule expression. Results show a homology in phenotype expression of both molecules (CD5 and CD6, what associated with the fact that both lymphocyte receptors are physically linked, allow to suggest that CD6 molecule is a interesting biological marker in prognosis assessment, and the possibility of new therapeutic variants in this disease.

Production of human anti-HLA monoclonal antibodies

Energy Technology Data Exchange (ETDEWEB)

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

1986-03-01

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

CD47 is a Potential Target for the Treatment of Laryngeal Squamous Cell Carcinoma

Directory of Open Access Journals (Sweden)

ChunPing Yang

2016-11-01

Full Text Available Background/Aims: This study aims to investigate the effect of CD47 on the development of laryngeal squamous cell carcinoma (LSCC and the therapeutic potential of monoclonal antibody against CD47 and its ligand SIRPα in the treatment of LSCC. Methods: We firstly detected the expressions of CD47 mRNA and protein in LSCC and para-carcinoma tissues, introduced the most efficient CD47siRNA sequence into LSCC cells by lentiviral transfection and employed three monoclonal antibodies to evaluate their anti-LSCC effects in vitro and in vivo. Results: We observed that the mRNA and protein expressions of CD47 in LSCC tissue had significant increase in LSCC tissues compared with those in para-carcinoma tissue (p Conclusion: The results suggested a critical role of CD47 in LSCC development and the promising treatment of antiCD47/SIRPα and/or CD47siRNA in LSCC.

Radioimmunotherapy of indolent non-Hodgkin's lymphoma with Yttrium-90 labeled anti-CD20 monoclonal antibody therapy does not preclude subsequent chemotherapy or autologous hematologic stem cell transplantation therapy in most patients

International Nuclear Information System (INIS)

Wiseman, G.A.; Witzig, T.E.; Ansell, S.M.; Ristow, K.M.

2002-01-01

Introduction: Yttrium-90 (Y-90) labeled anti-CD20 monoclonal antibody (ibritumomab tiuxetan or Zevalin TM ) is a novel therapy for patients with relapsed CD20+ B-cell non-Hodgkin's lymphoma (NHL). Patients treated with Zevalin radioimmunotherapy (RIT) are limited from higher doses due to transient and reversible platelet and neutrophil suppression. Patients with indolent NHL who relapse or are refractory to chemotherapy have a 70-80% overall response rate and a 20-30% complete response rate when treated with Zevalin RIT. Therefore additional treatment is required in a minority of patients shortly after Zevalin therapy and in many others at relapse. Relapsed patients are generally treated with chemotherapy alone or high dose chemotherapy followed by autologous transplantation. We wanted to evaluate the ability of patients to tolerate subsequent therapy given at relapse following Zevalin RIT. Methods: We had 58 patients who relapsed after receiving Zevalin RIT and later received additional therapy. The clinical records and lab results were reviewed and compared with a matched control group of patients treated prior to Zevalin availability who received chemotherapy without prior Zevalin RIT. Results: The toxicity in 58 patients treated with Zevalin RIT and subsequent therapy was not significantly different from the control group who did not receive Zevalin RIT. Patients had a median of two subsequent therapies (range, 1-7) after Zevalin. Twenty eight percent required blood cell growth factor support with subsequent chemotherapy and 2 patients required reductions from the standard chemotherapy doses due to prolonged myelosuppression. Eight patients subsequently had successful autologous hematologic stem cell transplant with cells collected after Zevalin. Thirteen of the 58 patients (28%) treated with standard dose chemotherapy were hospitalized for neutropenic fever or thrombocytopenia. Conclusions: Chemotherapy or high dose chemotherapy with autologous transplantation

A short CD3/CD28 costimulation combined with IL-21 enhance the generation of human memory stem T cells for adoptive immunotherapy.

Science.gov (United States)

Alvarez-Fernández, C; Escribà-Garcia, L; Vidal, S; Sierra, J; Briones, J

2016-07-19

Immunotherapy based on the adoptive transfer of gene modified T cells is an emerging approach for the induction of tumor-specific immune responses. Memory stem T cells, due to their enhanced antitumor and self-renewal capacity, have become potential candidate for adoptive T cell therapy of cancer. Methods to generate memory stem T cells ex vivo rely on CD3/CD28 costimulation and the use of cytokines such as IL-7 and IL-15 during the entire culture period. However, a strong costimulation may induce differentiation of memory stem T cells to effector memory T cells. Here we show that manipulation of the length of the costimulation and addition of IL-21 enhance the ex vivo expansion of memory stem T cells. Purified naïve T cells from healthy donors were cultured in the presence of anti-CD3/CD28 coated beads, IL-7, IL-15 and/or IL-21 (25 ng/ml). T cells phenotype from the different memory and effector subpopulations were analyzed by multiparametric flow cytometry. A short anti-CD3/CD28 costimulation of naïve T cells, combined with IL-7 and IL-15 significantly increased the frequencies of CD4(+) and CD8(+) memory stem T cells ex vivo, compared to a prolonged costimulation (34.6 ± 4.4 % vs 15.6 ± 4.24 % in CD4(+); p = 0.008, and 20.5 ± 4.00 % vs 7.7 ± 2.53 % in CD8(+); p = 0.02). Moreover, the addition of IL-21 to this condition further enhanced the enrichment and expansion of CD4(+) and CD8(+) memory stem T cells with an increase in the absolute numbers (0.7 × 10(6) ± 0.1 vs 0.26 × 10(6) ± 0.1 cells for CD4(+); p = 0.002 and 1.1 × 10(6) ± 0.1 vs 0.27 × 10(6) ± 0.1 cells for CD8(+); p = 0.0002; short + IL-21 vs long). These new in vitro conditions increase the frequencies and expansion of memory stem T cells and may have relevant clinical implications for the generation of this memory T cell subset for adoptive cell therapy of patients with cancer.

Systemic agonistic anti-CD40 treatment of tumor bearing mice modulates hepatic myeloid suppressive cells and causes immune-mediated liver damage

Science.gov (United States)

Medina-Echeverz, José; Ma, Chi; Duffy, Austin; Eggert, Tobias; Hawk, Nga; Kleiner, David E.; Korangy, Firouzeh; Greten, Tim F.

2015-01-01

Immune stimulatory monoclonal antibodies are currently evaluated as anti tumor agents. Although overall toxicity appears to be moderate, liver toxicities have been reported and are not completely understood. We studied the effect of systemic CD40 antibody treatment on myeloid cells in spleen and liver. Naïve and tumor-bearing mice were treated systemically with agonistic anti-CD40 antibody. Immune cell subsets in liver and spleen, serum transaminases and liver histologies were analyzed after antibody administration. Nox2−/−, Cd40−/− as well as bone marrow chimeric mice were used to study the mechanism by which agonistic anti-CD40 mediates its effects in vivo. Suppressor function of murine and human tumor-induced myeloid derived suppressive cells was studied upon CD40 ligation. Agonistic CD40 antibody caused liver damage within 24 hours after injection in two unrelated tumor models and mice strains. Using bone marrow chimeras we demonstrated that CD40 antibody-induced hepatitis in tumor-bearing mice was dependent on the presence of CD40-expressing hematopoietic cells. Agonistic CD40 ligation-dependent liver damage was induced by the generation of reactive oxygen species. Furthermore, agonistic CD40 antibody resulted in increased CD80 and CD40 positive liver CD11b+Gr-1+ immature myeloid cells. CD40 ligation on tumor-induced murine and human CD14+HLA-DRlow PBMC from cancer patients reduced their immune suppressor function. Collectively, agonistic CD40 antibody treatment activated tumor-induced, myeloid cells, caused myeloid dependent hepatotoxicity and ameliorated the suppressor function of murine and human MDSC. Collectively, our data suggests that CD40 may mature immunosuppressive myeloid cells and thereby cause liver damage in mice with an accumulation of tumor-induced hepatic MDSC. PMID:25637366

Increased Numbers of CD4+CD25+ and CD8+CD25+ T-Cells in Peripheral Blood of Patients with Rheumatoid Arthritis with Parvovirus B19 Infection.

Science.gov (United States)

Naciute, Milda; Maciunaite, Gabriele; Mieliauskaite, Diana; Rugiene, Rita; Zinkeviciene, Aukse; Mauricas, Mykolas; Murovska, Modra; Girkontaite, Irute

2017-01-01

To investigate T-cell subpopulations in peripheral blood of human parvovirus B19 DNA-positive (B19 + ) and -negative (B19 - ) patients with rheumatoid arthritis (RA) and healthy persons. Blood samples were collected from 115 patients with RA and 47 healthy volunteers; 27 patients with RA and nine controls were B19 + Cluster of differentiation (CD) 4, 8, 25 and 45RA were analyzed on blood cells. CD25 expression on CD4 + CD45RA + , CD4 + CD45RA - , CD8 + CD45RA + , CD8 + CD45RA - subsets were analyzed by flow cytometry. The percentage of CD25 low and CD25 hi cells was increased on CD4 + CD45RA + , CD4 + CD45RA - T-cells and the percentage of CD25 + cells was increased on CD8 + CD45RA + , CD8 + CD45RA - T-cells of B19 + patients with RA in comparison with B19 - patients and controls. Raised levels of CD4 and CD8 regulatory T-cells in B19 + RA patients could cause down-regulation of antiviral clearance mechanisms and lead to activation of persistent human parvovirus B19 infection in patients with RA. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

1,25-dihydroxyvitamin D3 and dexamethasone increase interleukin-10 production in CD4+ T cells from patients with Crohn's disease

DEFF Research Database (Denmark)

Bartels, Lars Erik; Jørgensen, Søren Peter; Agnholt, Jørgen

2007-01-01

,25-dihydroxyvitamin D3 with and without DEX could induce IL-10 production, downregulate pro-inflammatory Interferon (IFN)-gamma and Tumor Necrosis Factor (TNF)-alpha production, and influence cell kinetics in peripheral CD4+ T cells from CD patients. METHODS: CD4+ T cells were separated from peripheral blood from CD......BACKGROUND AND AIM: In Crohn's disease (CD), epidemiological data and animal studies suggest that vitamin D (vitD) has protective immune-modulating properties. 1,25-dihydroxyvitamin D3 and dexamethasone (DEX) induce interleukin (IL)-10 productions in healthy controls (HC) T cells. We studied if 1...... patients and HC. Cells were activated by anti-CD3 and anti-CD28 in the presence of 1,25-dihydroxyvitamin D3 and/or DEX. Cytokine levels, proliferation, and apoptosis were measured following 7 days of culture. RESULTS: In T cells from CD patients, 1,25-dihydroxyvitamin D3 and DEX increased IL-10 production...

Sensitive Detection of the Natural Killer Cell-Mediated Cytotoxicity of Anti-CD20 Antibodies and Its Impairment by B-Cell Receptor Pathway Inhibitors

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Floyd Hassenrück

2018-01-01

Full Text Available The antibody-dependent cell-mediated cytotoxicity (ADCC of the anti-CD20 monoclonal antibodies (mAbs rituximab and obinutuzumab against the cell line Raji and isolated CLL cells and its potential impairment by kinase inhibitors (KI was determined via lactate dehydrogenase release or calcein retention, respectively, using genetically modified NK92 cells expressing CD16-176V as effector cells. Compared to peripheral blood mononuclear cells, recombinant effector cell lines showed substantial alloreactivity-related cytotoxicity without addition of mAbs but afforded determination of ADCC with reduced interassay variability. The cytotoxicity owing to alloreactivity was less susceptible to interference by KI than the ADCC of anti-CD20 mAbs, which was markedly diminished by ibrutinib, but not by idelalisib. Compared to rituximab, the ADCC of obinutuzumab against primary CLL cells showed approximately 30% higher efficacy and less interference with KI. Irreversible BTK inhibitors at a clinically relevant concentration of 1 μM only weakly impaired the ADCC of anti-CD20 mAbs, with less influence in combinations with obinutuzumab than with rituximab and by acalabrutinib than by ibrutinib or tirabrutinib. In summary, NK cell line-based assays permitted the sensitive detection of ADCC of therapeutic anti-CD20 mAbs against CLL cells and of the interference of KI with this important killing mechanism.

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

Science.gov (United States)

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

1991-09-01

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

Radioiodination of monoclonal antibody intact anti-CEA

International Nuclear Information System (INIS)

Okada, H.; Souza, I.T.T.; Silva, C.P.G.

1990-11-01

The purpose of this study is to examine a convenient system that can be used to iodinate monoclonal antibodies which is rapid, simple, efficient and reproducible, and which can be accomplished in radiopharmaceutical laboratories. It is important to remember that antibodies are sensitive biochemicals, subject to losses of the activity that is essential to their mode of action, namely the ability to bind specific antigen. The advent of solid phase iodination agents has greatly expanded the range of gentle iodination techniques available for iodinating sensitive biological materials. The agent most widely used is the Iodogen (1,3,4,6 tetrachloro-3a-6a diphenylglycoluril) method. Anti-CEA 4C sub(11) IgG sub(2a,k) (prepared in the Ludwig Institute-Sao Paulo-Brazil ) is used as model to evaluate the Iodogen methodology. The miniature chromatographic system, also rapid, accurate, simple, efficient was elaborated to determine the labelling efficiency incorporation of iodine into immunoglobulin, and the radiochemical purity of sup(131)I-anti-CEA. (author)

Compartmental and dosimetric studies of anti-CD20 labelled with {sup 188}Re; Estudo compartimental e dosimetrico do Anti-CD20 marcado com {sup 188}Re

Energy Technology Data Exchange (ETDEWEB)

Kuramoto, Graciela Barrio

2016-10-01

}Luanti- CD20, the γ emitter {sup 99m}Tc-Anti-CD20 and α emitter {sup 211}At-Anti-CD20 presented a elimination constant of approximately 0.05 hours{sup -1} in the animal's blood. The dosimetric evaluation of {sup 188}Re-Anti-CD20 was performed using two methodologies: the Monte Carlo method and the use of a point source β{sup -}by Formula Loevinger by Excel program. In the Formula Loevinger, there was a validation of the Monte Carlo method for dosimetry of {sup 188}Re-Anti-CD20 and other products. The doses and dose rates obtained by the two methods were evaluated in comparison with {sup 90}Y-Anti-CD20, {sup 131}I-Anti-CD20 and {sup 177}Lu-Anti-CD20 dosimetry, obtained by the same methodology. The dose study was conducted using mathematical models considering a nude mouse 25 g, simulating different tumor sizes and different forms of distribution of the product within the animal. According to the results, the energy emission β{sup -}, {sup 188}Re- Anti-CD20 has a higher energy deposition for large tumors when compared to other products evaluated. In a simulation with 100% of the product uptake by tumor, 89% of the total dose remained absorbed by the tumor, while preserving the integrity of critical ógãos as heart (2%), lung (5%), column (4%), liver (0.014%) and kidneys 9 (0.0007%). In a simulation where there is a biodistribution of the product in the animal organism, 38% of the total dose absorbed by the tumor and >3% is absorbed by the column. In this situation closer to reality, the extrapolation of the data for a 70kg human, showed that the absorbed dose to tumor corresponds to about 33%; In column 7% and the heart would receive a dose of 35% of the total. The compartmental analysis and dosimetric presented in this work, performed through use of an animal model for the {sup 188}Re-anti-CD20 shows that the product developed and presented in the literature is promising candidate for RIT. (author)

Circulating CD4+CD28null T Cells May Increase the Risk of an Atherosclerotic Vascular Event Shortly after Kidney Transplantation

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Michiel G. H. Betjes

2013-01-01

Full Text Available Proinflammatory CD4+ T cells without the costimulatory molecule CD28 (CD4+CD28null T cells are expanded in patients with end-stage renal disease (ESRD and associated with atherosclerotic vascular events (AVE. In a prospective study, the number of circulating CD4+CD28null T cells was established in 295 ESRD patients prior to receiving a kidney allograft. Within the first year after transplantation, an AVE occurred in 20 patients. Univariate analysis showed that besides a history of cardiovascular disease (CVDpos, HR 8.1, , age (HR 1.04, , dyslipidaemia (HR 8.8, , and the % of CD4+CD28null T cells (HR 1.04 per % increase, 95% CI 1.00–1.09, were significantly associated with the occurrence of a posttransplantation AVE. In a multivariate analysis, only CVDpos remained a significant risk factor with a significant and positive interaction between the terms CVDpos and the % of CD4+CD28null T cells (HR 1.05, 95% CI 1.03–1.11, . Within the CVDpos group, the incidence of an AVE was 13% in the lowest tertile compared to 25% in the highest tertile of % of CD4+CD28null T cells. In conclusion, the presence of circulating CD4+CD28null T cells is associated with an increased risk for a cardiovascular event shortly after kidney transplantation.

EFFECT OF LIPOSOMAL CLODRONATE-DEPENDENT DEPLETION OF PROFESSIONAL ANTIGEN PRESENTING CELLS ON NUMBERS AND PHENOTYPE OF CANINE CD4+CD25+FOXP3+ REGULATORY T CELLS

Science.gov (United States)

Weaver, Kriston F.; Stokes, John V.; Gunnoe, Sagen A.; Follows, Joyce S.; Shafer, Lydia; Ammari, Mais G.; Archer, Todd M.; Thomason, John M.; Mackin, Andrew J.; Pinchuk, Lesya M.

2015-01-01

Regulatory T cells (Tregs) are known to control autoreactivity during and subsequent to the development of the peripheral immune system. Professional antigen presenting cells (APCs), dendritic cells (DCs) and monocytes, have an important role in inducing Tregs. For the first time, this study evaluated proportions and phenotypes of Tregs in canine peripheral blood depleted of professional APCs, utilizing liposomal clodronate (LC) and multicolor flow cytometry analysis. Our results demonstrate that LC exposure promoted short term decreases followed by significant increases in the proportions or absolute numbers of CD4+CD25+FOXP3+ Tregs in dogs. In general, the LC-dependent Treg fluctuations were similar to the changes in the levels of CD14+ monocytes in Walker hounds. However, the proportions of monocytes showed more dramatic changes compared to the proportions of Tregs that were visually unchanged after LC treatment over the study period. At the same time, absolute Treg numbers showed, similarly to the levels of CD14+ monocytes, significant compensatory gains as well as the recovery during the normalization period. We confirm the previous data that CD4+ T cells with the highest CD25 expression were highly enriched for FOXP3. Furthermore, for the first time, we report that CD4+CD25lowFOXP3+ is the major regulatory T cell subset affected by LC exposure. The increases within the lowest CD25 expressers of CD4+FOXP3+ cells together with compensatory gains in the proportion of CD14+ monocytes during compensatory and normalization periods suggest the possible direct or indirect roles of monocytes in active recruitment and generation of Tregs from naïve CD4+ T cells. PMID:25950023

Effectiveness and side effects of anti-CD20 therapy for autoantibody-mediated blistering skin diseases: A comprehensive survey of 71 consecutive patients from the Initial use to 2007

Directory of Open Access Journals (Sweden)

Jennifer D Peterson

2008-11-01

Full Text Available Jennifer D Peterson1, Lawrence S Chan2,3,41Department of Dermatology, Texas Tech University Health Sciences Center at Lubbock, Lubbock, TX, USA; 2Department of Dermatology; 3Department of Microbiology/Immunology, University of Illinois at Chicago, Chicago, IL, USA; 4Medicine Service, Jesse Brown VA Medical Center, Chicago, IL, USAAbstract: In order to examine the efficacy and side effects of the monoclonal antibody anti-CD20 (rituximab on autoimmune blistering skin diseases, we performed a comprehensive survey of 71 consecutive patients from initial use up to 2007, using the PubMed database. A heterogeneous group of patients, including 51 patients with pemphigus vulgaris, one with pemphigus vegetans, nine with pemphigus foliaceus, five with paraneoplastic pemphigus, four with epidermolysis bullosa acquisita, and one with both bullous pemphigoid and graft vs host disease was included in this survey. Overall the monoclonal antibody seems to be effective in that 69% of patients showed complete response, 25% of patients showed partial response, whereas 6% of patients showed progressive disease. Six deaths occurred in association with the treatment, with four of these deaths in patients with paraneoplastic pemphigus, a disease characteristically resistant to conventional medication and with a high mortality rate. Of note, 11 patients who received combined rituximab and intravenous immune globulin treatments had the best outcome: complete response without any serious side effects. Therefore further investigation on rituximab with controlled clinical trial is a worthy pursuit.Keywords: blistering diseases, skin, anti-CD20, pemphigus, epidermolysis bullosa acquisita

Evaluación de los reactivos hemoclasificadores monoclonales cubanos HEMO CIM ANTI-A y HEMO CIM ANTI-B en pacientes VIH/SIDA Evaluation of the Cuban anti-A Hemo CIM and anti-B Hemo CIM monoclonal hemoclassifiers in HIV/AIDS patients

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Ananidia Rivero

2000-12-01

Full Text Available Se describe un estudio realizado con los hemoclasificadores monoclonales cubanos Hemo CIM anti-A y anti-B producidos por el Centro de Inmunología Molecular (CIM y comercializados por CIMAB S.A, para ser evaluados en pacientes VIH/SIDA. Se analizaron un total de 130 pacientes en el Servicio de Transfusiones del Instituto "Pedro Kourí". Se utilizaron en paralelo los antisueros policlonales de producción nacional (Laboratorios Betera y los reactivos monoclonales comerciales producidos y donados por International Blood Group Reference Laboratory; Bristol, UK. Se demostró que los reactivos Hemo CIM anti-A y Hemo CIM anti-B se comportaron de forma similar a sus homólogos comerciales y policlonales. Al comparar la efectividad de la aglutinación para los 3 reactivos pudimos comprobar que con el reactivo monoclonal, Hemo CIM anti-A y anti-B se obtuvieron los mejores resultados expresados en crucesA study conducted with the Cuban anti-A and anti-B Hemo CIM monoclonal hemoclassifiers produced by the Center of Molecular Immunology (CMI and commercialized by CIMAB S.A. to be evaluated in HIV/AIDS patients is described. 130 patients were analyzed at the Service of Transfusions of "Pedro Kouri" Institute. The polyclonal antisera of national production (Betera Laboratories and the commercial monoclonal reagents produced and donated by the International Blood Group Reference Laboratory; Bristol, UK, were used at the same time. It was proved that the anti-A Hemo CIM and anti-B Hemo CIM reagents behaved similarly to their commercial and polyclonal homologues. On comparing the effectiveness of the agglutination for the 3 reagents, we were able to verify that the best results expressed in crosses were obtained with the anti-A and anti-B Hemo CIM monoclonal reagents

CD25 shedding by human natural occurring CD4+CD25+ regulatory T cells does not inhibit the action of IL-2

DEFF Research Database (Denmark)

Pedersen, Anders Elm; Lauritsen, Jens Peter Holst

2009-01-01

Tregs are known to inhibit CD4+ T cell in a contact-dependent manner, but at the same time, various suppressive factors are secreted. We, here, demonstrate that human naturally occurring CD4+CD25+ Tregs are able to shed large amounts of soluble CD25 upon activation. Secretion of sCD25 could add......Regulatory T (Treg) cells are important for the maintenance of peripheral tolerance and inhibition of pathogenic T-cell responses. Therefore, they are important for the limitation of chronic inflammation but can also be deleterious by e.g. limiting antitumour immune responses. Natural occurring...... to the inhibitory effect of Tregs as such secretion in other settings has been proposed to act as a sink for local IL-2. However, we here demonstrate that supernatant from human Tregs containing high concentration of sCD25 does not inhibit proliferation of CD4+CD25(-) T cells or inhibit the action of IL-2...

Change of CD20 Expression in Diffuse Large B-Cell Lymphoma Treated with Rituximab, an Anti-CD20 Monoclonal Antibody: A Study of the Osaka Lymphoma Study Group

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Naoki Wada

2009-10-01

Full Text Available Change of CD20 expression was examined in cases of diffuse large B-cell lymphoma (DLBCL. CD20 expression after treatment with anti-CD20 antibody (rituximab, Rx for DLBCL was examined in 23 cases who received serial biopsy by immunohistochemistry (IHC and flow cytometry (FCM. CD20– by IHC and/or FCM was defined as CD20–. Four cases were CD20– at initial biopsy but became CD20+ after chemotherapy with Rx (CH-R (group A. Recurrent tumors in three group A cases became resistant to CH-R. Initial and recurrent tumors were CD20+ before and after CH-R in 17 cases (group B. Tumors before CH-R were CD20– in two cases (group C and continued to be CD20– in one and turned CD20+ in the other with survival time after the relapse of 8 and 23 months, respectively. Evaluation of CD20 expression with immunohistochemical and flow cytometric methods is used for the prediction of responsiveness of relapsed DLBCL for CH-R.

Effects of CD44 Ligation on Signaling and Metabolic Pathways in Acute Myeloid Leukemia

KAUST Repository

Madhoun, Nour Y.

2017-01-01

Acute myeloid leukemia (AML) is characterized by a blockage in the differentiation of myeloid cells at different stages. CD44-ligation using anti-CD44 monoclonal antibodies (mAbs) has been shown to reverse the blockage of differentiation

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

NARCIS (Netherlands)

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

1997-01-01

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

Prediction of Short- and Medium-term Efficacy of Biosimilar Infliximab Therapy. Do Trough Levels and Antidrug Antibody Levels or Clinical And Biochemical Markers Play the More Important Role?

Science.gov (United States)

Gonczi, Lorant; Vegh, Zsuzsanna; Golovics, Petra Anna; Rutka, Mariann; Gecse, Krisztina Barbara; Bor, Renata; Farkas, Klaudia; Szamosi, Tamás; Bene, László; Gasztonyi, Beáta; Kristóf, Tünde; Lakatos, László; Miheller, Pál; Palatka, Károly; Papp, Mária; Patai, Árpád; Salamon, Ágnes; Tóth, Gábor Tamás; Vincze, Áron; Biro, Edina; Lovasz, Barbara Dorottya; Kurti, Zsuzsanna; Szepes, Zoltan; Molnár, Tamás; Lakatos, Péter L

2017-06-01

Biosimilar infliximab CT-P13 received European Medicines Agency [EMA] approval in June 2013 for all indications of the originator product. In the present study, we aimed to evaluate the predictors of short- and medium-term clinical outcome in patients treated with the biosimilar infliximab at the participating inflammatory bowel disease [IBD] centres in Hungary. Demographic data were collected and a harmonised monitoring strategy was applied. Clinical and biochemical activities were evaluated at Weeks 14, 30, and 54. Trough level [TL] and anti-drug antibody [ADA] concentrations were measured by enzyme-linked immunosorbent assay [ELISA] [LT-005, Theradiag, France] at baseline at 14, 30 and 54 weeks and in two centres at Weeks 2 and 6. A total of 291 consecutive IBD patients (184 Crohn's disease [CD] and 107 ulcerative colitis [UC]) were included. In UC, TLs at Week 2 predicted both clinical response and remission at Weeks 14 and 30 (clinical response/remission at Week 14: area under the curve [AUC] = 0.81, p < 0.001, cut-off: 11.5 μg/ml/AUC = 0.79, p < 0.001, cut-off: 15.3μg/ml; clinical response/remission at Week 30: AUC = 0.79, p = 0.002, cut-off: 11.5 μg/ml/AUC = 0.74, p = 0.006, cut-off: 14.5 μg/ml), whereas ADA positivity at Week 14 was inversely associated with clinical response at Week 30 [58.3% vs 84.8% ,p = 0.04]. Previous anti-tumour necrosis factor [TNF] exposure was inversely associated with short-term clinical remission [Week 2: 18.8% vs 47.8%, p = 0.03, at Week 6: 38.9% vs 69.7%, p = 0.013, at Week 14: 37.5% vs 2.5%, p = 0.06]. In CD, TLs at Week 2 predicted short-term [Week 14 response/remission, AUCTLweek2 = 0.715-0.721, p = 0.05/0.005] but not medium-term clinical efficacy. In addition, early ADA status by Week 14 [p = 0.04-0.05 for Weeks 14 and 30], early clinical response [p < 0.001 for Weeks 30/54] and normal C-reactive protein [CRP] at Week 14 [p = 0.005-0.0001] and previous anti-TNF exposure [p = 0.03-0.0001 for Weeks 14, 30, and 54] were

Changes and clinical significance of CD4+CD25+CD127- regulatory T cells in Graves disease

International Nuclear Information System (INIS)

Zou Jintao; Yu Peiling; Dong Jingwei; Liao Qihong; Liu Dongliang; Zeng Hongyi

2012-01-01

Objective: To investigate the mechanism of Graves disease by observing the changes of CD4 + CD25 + CD127 - regulatory T cells (Treg) population in the patients. Methods: Flow cytometry was used to detect the proportion of CD4 + CD25 + CD127 - Treg of CD4 + T cells in 90 Graves disease patients (Graves disease group) and 50 healthy adults (control group). Thyroid function and autoantibody levels were determined simultaneously. The t test was adopted for comparison between groups. The relationship between CD4 + CD25 + CD127 - Treg and thyroid function was analyzed by linear correlation analysis. Results: The percentages of CD4 + CD25 + CD127 - Treg in Graves disease group and control group were 1.39%±1.09% and 4.59%±1.14% separately. There was significant difference between the two groups (t=16.4, P<0.01). There were negative correlation between CD4 + CD25 + CD127 - Treg percentages and total triiodothyronine, total thyroxine,free triiodothyronine, free thyroxine and thyrotropin receptor antibody,thyroglobulin antibody, thyroid microsomal antibody (r=-0.62, -0.65, -0.56, -0.71, -0.50, -0.15, all P<0.01). Conclusions: The reduction of CD4 + CD25 + CD127 - Treg percentages in Graves disease group and close relations of CD4 + CD25 + CD127 - Treg with thyroid function and thyroid autoantibody levels suggest that CD4 + CD25 + CD127 - Treg decrease in the number may be associated with the onset of Graves disease. CD4 + CD25 + CD127 - may be the specific marker of Treg. (authors)

Compartmental and dosimetric studies of anti-CD20 labelled with 188Re

International Nuclear Information System (INIS)

Kuramoto, Graciela Barrio

2016-01-01

-1 in the animal's blood. The dosimetric evaluation of 188 Re-Anti-CD20 was performed using two methodologies: the Monte Carlo method and the use of a point source β - by Formula Loevinger by Excel program. In the Formula Loevinger, there was a validation of the Monte Carlo method for dosimetry of 188 Re-Anti-CD20 and other products. The doses and dose rates obtained by the two methods were evaluated in comparison with 90 Y-Anti-CD20, 131 I-Anti-CD20 and 177 Lu-Anti-CD20 dosimetry, obtained by the same methodology. The dose study was conducted using mathematical models considering a nude mouse 25 g, simulating different tumor sizes and different forms of distribution of the product within the animal. According to the results, the energy emission β - , 188 Re- Anti-CD20 has a higher energy deposition for large tumors when compared to other products evaluated. In a simulation with 100% of the product uptake by tumor, 89% of the total dose remained absorbed by the tumor, while preserving the integrity of critical ógãos as heart (2%), lung (5%), column (4%), liver (0.014%) and kidneys 9 (0.0007%). In a simulation where there is a biodistribution of the product in the animal organism, 38% of the total dose absorbed by the tumor and >3% is absorbed by the column. In this situation closer to reality, the extrapolation of the data for a 70kg human, showed that the absorbed dose to tumor corresponds to about 33%; In column 7% and the heart would receive a dose of 35% of the total. The compartmental analysis and dosimetric presented in this work, performed through use of an animal model for the 188 Re-anti-CD20 shows that the product developed and presented in the literature is promising candidate for RIT. (author)

25 CFR 20.504 - What short-term homemaker services can Child Assistance pay for?

Science.gov (United States)

2010-04-01

... (protective) supervision; (b) A severely handicapped or special needs child whose care places undue stress on... 25 Indians 1 2010-04-01 2010-04-01 false What short-term homemaker services can Child Assistance... SERVICES FINANCIAL ASSISTANCE AND SOCIAL SERVICES PROGRAMS Child Assistance How Child Assistance Funds Can...

Short-term fasting protects mice against γ ray radiation

International Nuclear Information System (INIS)

Zhu Shengnan; Gu Xiuling; Song Lian; Tong Jian; Li Jianxiang

2012-01-01

Objective: To investigate the antagonistic effects of short-term fasting against 60 Co γ ray radiation. Methods: After fasting ICR mice were irradiated for 3 min at a dose rate of 2.5 Gy/min and then returned to normal diet. General situation, body weight changes, food consumption and toxic status were observed. WBC, organ index and anti-oxidative ability (ROS, SOD, MDA, T-AOC) were analyzed. Results: After 60 Co γ ray radiation, the mice exhibited severe toxic symptoms before death. The survival rates were 0 for control and 12 h group, 12.5% for 48 h group and 50% for 72 h group respectively. ROS production of 72 h group was reduced compared with 0 h group (P<0.05). Conclusion: Short-term fasting may attenuate radiation induced injuries, evidenced by a significant increase in mice survival rate. (authors)

CD117 expression on blast cells in acute myeloid leukemia

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Goryainova N.V.

2015-09-01

Full Text Available The aim of the present work was to analyze the frequency of CD117 (c-KIT antigen expression on the blast cells in acute myeloid leukemia (AML, evaluation of the presence of the relationship between the expression of the c-KIT and leukemia according to the FAB classification and definition of co-expression of the antigen CD117, antigens CD33 and CD34. The data of 47 patients with AML were diagnosed. M0 AML variant was established in 3 (6% patients, M1 – in 2 (4%, M2 – in 9 (20%, M4 – in 22 (47% and M5 – in 11 (23%. For immunophenotypic stu¬dies monoclonal antibodies (mAb that detect antigens of anti-CD34, anti-CD33 and anti-CD117 (Becton Dickinson, USA were used. The presence of the antigen CD117 was detected in 39 people, accounting for 83% of all surveyed. Antigen c-KIT was present in 48.117.0% cells on average: in all 3 cases – AML M0, in2 cases of AML M1, in 6 cases – AML M2, 20 of 22 cases – AML M4 and in 8 of 11 AML M5 cases. Average levels of CD117 in investigated leukemia cases statistically differed significantly (p=0.0067. Among 39 CD117- positive patients in 25 (53% co-expression of CD117+/CD34+ was revealed. Expression of CD117+/CD34- was observed in 14 cases (30%, CD117-/CD34+ – in 4 cases (8,5%, CD117-/CD34- – in 4 cases (8.5%. CD34 had of 64% of cells of myeloid origin. A high positive cor¬relation between expression of CD117 and CD34 (r=+0,5169 was determined, being statistically significant (p0,0067.

Broad-spectrum inhibition of HIV-1 by a monoclonal antibody directed against a gp120-induced epitope of CD4.

Science.gov (United States)

Burastero, Samuele E; Frigerio, Barbara; Lopalco, Lucia; Sironi, Francesca; Breda, Daniela; Longhi, Renato; Scarlatti, Gabriella; Canevari, Silvana; Figini, Mariangela; Lusso, Paolo

2011-01-01

To penetrate susceptible cells, HIV-1 sequentially interacts with two highly conserved cellular receptors, CD4 and a chemokine receptor like CCR5 or CXCR4. Monoclonal antibodies (MAbs) directed against such receptors are currently under clinical investigation as potential preventive or therapeutic agents. We immunized Balb/c mice with molecular complexes of the native, trimeric HIV-1 envelope (Env) bound to a soluble form of the human CD4 receptor. Sera from immunized mice were found to contain gp120-CD4 complex-enhanced antibodies and showed broad-spectrum HIV-1-inhibitory activity. A proportion of MAbs derived from these mice preferentially recognized complex-enhanced epitopes. In particular, a CD4-specific MAb designated DB81 (IgG1Κ) was found to preferentially bind to a complex-enhanced epitope on the D2 domain of human CD4. MAb DB81 also recognized chimpanzee CD4, but not baboon or macaque CD4, which exhibit sequence divergence in the D2 domain. Functionally, MAb DB81 displayed broad HIV-1-inhibitory activity, but it did not exert suppressive effects on T-cell activation in vitro. The variable regions of the heavy and light chains of MAb DB81 were sequenced. Due to its broad-spectrum anti-HIV-1 activity and lack of immunosuppressive effects, a humanized derivative of MAb DB81 could provide a useful complement to current preventive or therapeutic strategies against HIV-1.

Broad-spectrum inhibition of HIV-1 by a monoclonal antibody directed against a gp120-induced epitope of CD4.

Directory of Open Access Journals (Sweden)

Samuele E Burastero

Full Text Available To penetrate susceptible cells, HIV-1 sequentially interacts with two highly conserved cellular receptors, CD4 and a chemokine receptor like CCR5 or CXCR4. Monoclonal antibodies (MAbs directed against such receptors are currently under clinical investigation as potential preventive or therapeutic agents. We immunized Balb/c mice with molecular complexes of the native, trimeric HIV-1 envelope (Env bound to a soluble form of the human CD4 receptor. Sera from immunized mice were found to contain gp120-CD4 complex-enhanced antibodies and showed broad-spectrum HIV-1-inhibitory activity. A proportion of MAbs derived from these mice preferentially recognized complex-enhanced epitopes. In particular, a CD4-specific MAb designated DB81 (IgG1Κ was found to preferentially bind to a complex-enhanced epitope on the D2 domain of human CD4. MAb DB81 also recognized chimpanzee CD4, but not baboon or macaque CD4, which exhibit sequence divergence in the D2 domain. Functionally, MAb DB81 displayed broad HIV-1-inhibitory activity, but it did not exert suppressive effects on T-cell activation in vitro. The variable regions of the heavy and light chains of MAb DB81 were sequenced. Due to its broad-spectrum anti-HIV-1 activity and lack of immunosuppressive effects, a humanized derivative of MAb DB81 could provide a useful complement to current preventive or therapeutic strategies against HIV-1.

Clinical observation in nasopharyngeal carcinoma (NPC) treated with the anti-EGFR monoclonal antibody followed by helical tomotherapy

International Nuclear Information System (INIS)

Hou Jun; Feng Linchun; Cai Boning; Lu Na; Du Lei; Ma Lin; Xu Shouping; Xie Chuanbin

2011-01-01

Objective: To evaluate the clinical outcome and the acute toxicity in nasopharyngeal carcinoma (NPC) treated with tomotherapy followed by the anti-EGFR monoclonal antibody. Methods: Between March 2008 and November 2009, 34 newly diagnosed NPC patients were treated with helical tomotherapy combined with nimotuzumab or cetuximab. All the patients underwent tomotherapy at the dose of 70 Gy/33F for the gross tumor volume (pGTV ns ) and positive lymphnodes (GTV nd ), and 60 Gy/33F for the high risk clinical target volume (PTV 1 ), and 56 Gy/33 F for the low risk clinical target volume (PTV 2 ), respectively. 17 patients in group N were given weekly injection of 200 mg for 6-7 times and 17 patients in group C were given initial dosage 400 mg/m 2 followed by subsequent weekly dosage of 250 mg/m 2 for 6-7 times. Acute lesions were evaluated with the RTOG/EORTC criteria. Result: The median follow-up time was 22 months. The effective rates (CR + PR) in 3, 6 and 12 months were 14/17, 12/17, 12/17 in group N and 15/17, 14/17, 14/17 in group C. The 1 year survival rate was 15/17 in group Nand 17/17 in group C. Nimotuzumab had less acute mucositis reaction (u=2.25, P< 0.05), weight loss (t=2.56, P=0.02) and rash (u=4.36, P<0.01) compared with cetuximab. Conclusions: Helical tomotherapy combined with nimotuzumab or cetuximab was effective and made no difference in the short-term efficacy and 1 year survival rate for the patients with NPC. Nimotuzumab has less acute reaction than cetuximab. More studies should be done to prove long-term effects. (authors)

Therapeutic potential of an anti-high mobility group box-1 monoclonal antibody in epilepsy.

Science.gov (United States)

Zhao, Junli; Wang, Yi; Xu, Cenglin; Liu, Keyue; Wang, Ying; Chen, Liying; Wu, Xiaohua; Gao, Feng; Guo, Yi; Zhu, Junming; Wang, Shuang; Nishibori, Masahiro; Chen, Zhong

2017-08-01

Brain inflammation is a major factor in epilepsy, and the high mobility group box-1 (HMGB1) protein is known to contribute significantly to the generation of seizures. Here, we investigated the therapeutic potential of an anti-HMGB1 monoclonal antibody (mAb) in epilepsy. anti-HMGB1 mAb attenuated both acute seizure models (maximal electroshock seizure, pentylenetetrazole-induced and kindling-induced), and chronic epilepsy model (kainic acid-induced) in a dose-dependent manner. Meanwhile, the anti-HMGB1 mAb also attenuated seizure activities of human brain slices obtained from surgical resection from drug-resistant epilepsy patients. The mAb showed an anti-seizure effect with a long-term manner and appeared to be minimal side effects at even very high dose (no disrupted physical EEG rhythm and no impaired basic physical functions, such as body growth rate and thermoregulation). This anti-seizure effect of mAb results from its inhibition of translocated HMGB1 from nuclei following seizures, and the anti-seizure effect was absent in toll-like receptor 4 knockout (TLR4 -/- ) mice. Interestingly, the anti-HMGB1 mAb also showed a disease-modifying anti-epileptogenetic effect on epileptogenesis after status epileptics, which is indicated by reducing seizure frequency and improving the impaired cognitive function. These results indicate that the anti-HMGB1 mAb should be viewed as a very promising approach for the development of novel therapies to treat refractory epilepsy. Copyright © 2017 Elsevier Inc. All rights reserved.

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

Science.gov (United States)

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

2006-01-01

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

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

International Nuclear Information System (INIS)

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

1986-01-01

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

Epitope-dependent mechanisms of CD27 neutralization revealed by X-ray crystallography

Energy Technology Data Exchange (ETDEWEB)

Obmolova, Galina; Teplyakov, Alexey; Malia, Thomas J.; Wunderler, Nicole; Kwok, Deborah; Barone, Linda; Sweet, Raymond; Ort, Tatiana; Scully, Michael; Gilliland, Gary L. (Janssen)

2017-03-01

CD27 is a T and B cell co-stimulatory protein of the TNF receptor superfamily dependent on the availability of the TNF-like ligand CD70. Two anti-CD27 neutralizing monoclonal antibodies were obtained from mouse hybridoma and subsequently humanized and optimized for binding the target. The two antibodies are similar in terms of their CD27-binding affinity and ability to block NF-κB signaling, however their clearance rates in monkeys are very different. The pharmacokinetics profiles could be epitope dependent. To identify the epitopes, we determined the crystal structure of the ternary complex between CD27 and the Fab fragments of these non-competing antibodies. The structure reveals the binding modes of the antibodies suggesting that their mechanisms of action are distinctly different and provides a possible explanation of the in vivo data.

Dgroup: DG02651 [KEGG MEDICUS

Lifescience Database Archive (English)

Full Text Available ody Monoclonal antibody IL2RA (CD25) [HSA:3559] [KO:K05068] ... ... DG02651 Chemical ... DGroup Daclizumab ... D03639 ... Daclizumab (USAN/INN) ... Immunosuppressant, Anti-CD25 antib

Macrophage and NK-mediated killing of precursor-B acute lymphoblastic leukemia cells targeted with a-fucosylated anti-CD19 humanized antibodies.

Science.gov (United States)

Matlawska-Wasowska, K; Ward, E; Stevens, S; Wang, Y; Herbst, R; Winter, S S; Wilson, B S

2013-06-01

This work reports the tumoricidal effects of a novel investigational humanized anti-CD19 monoclonal antibody (Medi-551). An a-fucosylated antibody with increased affinity for human FcγRIIIA, Medi-551 is shown to mediate both antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP). Medi-551/CD19 complexes internalize slowly (>5 h) and thus remain accessible to effector cells for prolonged periods. We evaluated in vitro ADCC and ADCP activities of primary human natural killer (NK) cells and macrophages against precursor-B (pre-B) acute lymphoblastic leukemia (ALL) cell lines and pediatric patient blasts. Fluorescent imaging studies document immunological synapses formed between anti-CD19-bound target leukemia cells and effector cells and capture the kinetics of both NK-mediated killing and macrophage phagocytosis. Genetic polymorphisms in FcγRIIIA-158F/V modulate in vitro activities of effector cells, with FcγRIIIA-158V homozygotes or heterozygotes showing the strongest activity. Medi-551 treatment of severe combined immunodeficiency (SCID) mice engrafted with human pre-B cells led to prolonged animal survival and markedly reduced disease burden in blood, liver and bone marrow. These data show that anti-CD19 antibodies effectively recruit immune cells to pre-B ALL cells and support a move forward to early phase trials in this disease.

Short-term mechanisms influencing volumetric brain dynamics

Directory of Open Access Journals (Sweden)

Nikki Dieleman

2017-01-01

Full Text Available With the use of magnetic resonance imaging (MRI and brain analysis tools, it has become possible to measure brain volume changes up to around 0.5%. Besides long-term brain changes caused by atrophy in aging or neurodegenerative disease, short-term mechanisms that influence brain volume may exist. When we focus on short-term changes of the brain, changes may be either physiological or pathological. As such determining the cause of volumetric dynamics of the brain is essential. Additionally for an accurate interpretation of longitudinal brain volume measures by means of neurodegeneration, knowledge about the short-term changes is needed. Therefore, in this review, we discuss the possible mechanisms influencing brain volumes on a short-term basis and set-out a framework of MRI techniques to be used for volumetric changes as well as the used analysis tools. 3D T1-weighted images are the images of choice when it comes to MRI of brain volume. These images are excellent to determine brain volume and can be used together with an analysis tool to determine the degree of volume change. Mechanisms that decrease global brain volume are: fluid restriction, evening MRI measurements, corticosteroids, antipsychotics and short-term effects of pathological processes like Alzheimer's disease, hypertension and Diabetes mellitus type II. Mechanisms increasing the brain volume include fluid intake, morning MRI measurements, surgical revascularization and probably medications like anti-inflammatory drugs and anti-hypertensive medication. Exercise was found to have no effect on brain volume on a short-term basis, which may imply that dehydration caused by exercise differs from dehydration by fluid restriction. In the upcoming years, attention should be directed towards studies investigating physiological short-term changes within the light of long-term pathological changes. Ultimately this may lead to a better understanding of the physiological short-term effects of

Identification of bovine CD52-like molecule by monoclonal antibody IVA-543: distribution of CD52-like molecule in the bull genital tract

Czech Academy of Sciences Publication Activity Database

Michalková, K.; Simon, M.; Antalíková, J.; Klíma, Jiří; Horovská, L.; Jankovičová, J.; Hluchý, S.

2010-01-01

Roč. 74, č. 6 (2010), s. 1066-1074 ISSN 0093-691X Institutional research plan: CEZ:AV0Z50450515 Keywords : CD52 * monoclonal antibody * sperm * epididymis Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.045, year: 2010

Flow Cytometry Assessment of In Vitro Generated CD138+ Human Plasma Cells

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Rayelle Itoua Maïga

2014-01-01

Full Text Available The in vitro CD40-CD154 interaction promotes human B lymphocytes differentiation into plasma cells. Currently, CD138 is the hallmark marker enabling the detection of human plasma cells, both in vitro and in vivo; its presence can be monitored by flow cytometry using a specific antibody. We have developed a culture system allowing for the differentiation of memory B lymphocytes. In order to detect the newly formed plasma cells, we have compared their staining using five anti-CD138 monoclonal antibodies (mAbs. As a reference, we also tested human cell lines, peripheral blood mononuclear cells, and bone marrow samples. The five anti-CD138 mAbs stained RPMI-8226 cells (>98% with variable stain index (SI. The highest SI was obtained with B-A38 mAb while the lowest SI was obtained with DL-101 and 1D4 mAbs. However, the anti-CD138 mAbs were not showing equivalent CD138+ cells frequencies within the generated plasma cells. B-A38, B-B4, and MI-15 were similar (15–25% while DL-101 mAb stained a higher proportion of CD138-positive cells (38–42%. DL-101 and B-A38 mAbs stained similar populations in bone marrow samples but differed in their capacity to bind to CD138high and CD138lo cell lines. In conclusion, such cellular fluctuations suggest heterogeneity in human plasma cell populations and/or in CD138 molecules.

Daratumumab: a first-in-class CD38 monoclonal antibody for the treatment of multiple myeloma

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Larysa Sanchez

2016-06-01

Full Text Available Abstract Daratumumab is a human monoclonal antibody that targets CD38, a cell surface protein that is overexpressed on multiple myeloma (MM cells. Preclinical studies have shown that daratumumab induces MM cell death through several mechanisms, including complement-dependent cytotoxicity (CDC, antibody-dependent cell-mediated cytotoxicity (ADCC, antibody-dependent cellular phagocytosis (ADCP, and apoptosis. Given the encouraging efficacy and acceptable safety profile of daratumumab demonstrated in clinical trials, daratumumab has emerged as a novel treatment option for myeloma and became the first monoclonal antibody approved by the FDA for the treatment of MM.

Short-term stress enhances cellular immunity and increases early resistance to squamous cell carcinoma.

Science.gov (United States)

Dhabhar, Firdaus S; Saul, Alison N; Daugherty, Christine; Holmes, Tyson H; Bouley, Donna M; Oberyszyn, Tatiana M

2010-01-01

In contrast to chronic/long-term stress that suppresses/dysregulates immune function, an acute/short-term fight-or-flight stress response experienced during immune activation can enhance innate and adaptive immunity. Moderate ultraviolet-B (UV) exposure provides a non-invasive system for studying the naturalistic emergence, progression and regression of squamous cell carcinoma (SCC). Because SCC is an immunoresponsive cancer, we hypothesized that short-term stress experienced before UV exposure would enhance protective immunity and increase resistance to SCC. Control and short-term stress groups were treated identically except that the short-term stress group was restrained (2.5h) before each of nine UV-exposure sessions (minimum erythemal dose, 3-times/week) during weeks 4-6 of the 10-week UV exposure protocol. Tumors were measured weekly, and tissue collected at weeks 7, 20, and 32. Chemokine and cytokine gene expression was quantified by real-time PCR, and CD4+ and CD8+ T cells by flow cytometry and immunohistochemistry. Compared to controls, the short-term stress group showed greater cutaneous T-cell attracting chemokine (CTACK)/CCL27, RANTES, IL-12, and IFN-gamma gene expression at weeks 7, 20, and 32, higher skin infiltrating T cell numbers (weeks 7 and 20), lower tumor incidence (weeks 11-20) and fewer tumors (weeks 11-26). These results suggest that activation of short-term stress physiology increased chemokine expression and T cell trafficking and/or function during/following UV exposure, and enhanced Type 1 cytokine-driven cell-mediated immunity that is crucial for resistance to SCC. Therefore, the physiological fight-or-flight stress response and its adjuvant-like immuno-enhancing effects, may provide a novel and important mechanism for enhancing immune system mediated tumor-detection/elimination that merits further investigation.

Anti-CEA monoclonal antibody in the diagnosis of colorectal, lung and ovarian carcinoma

International Nuclear Information System (INIS)

Jiang, N.; Lu, B.; Lu, X.; Sha, X.; Yue, D.

2000-01-01

This study evaluated the diagnostic value of radioimmnoimaging (RII) with 99 Tc labeled monoclonal antibody C50, raised originally against carcinoembryonic antigen (anti-CEA) in various tumors. 152 pathologically confirmed patients with a tumor were imaged prior to surgery with an anti-CEA monoclonal antibody labeled with 99 Tc. There were 115 patients with ovarian carcinoma, 26 patients with colorectal carcinoma and 11 patients with lung carcinoma. Images were acquired at 3-6 h post injection and were analyzed by the double blind method. Images of patients with ovarian cancer were compared with B-ultrasound images. Immunohistochemical staining was performed on all cases of colorectal cancer. All RII images demonstrated excellent contrast, clear lesions, and no serious toxic or other side reactions occurred. Transient chills and fever were observed in 3 cases. This study showed a sensitivity=88.2%, specificity=83.2%, and an accuracy=4.0%. The smallest lesion size detected was 2 x 2 cm. The total combined lesion detection rate for primary, metastatic, and recurrence lesions was 84.4%. We conclude that 99 Tc labeled anti-CEA MoAb C50 can be used in the diagnosis of colorectal carcinoma, ovarian carcinoma, and lung carcinoma

The combination of anti-KIR monoclonal antibodies with anti-PD-1/PD-L1 monoclonal antibodies could be a critical breakthrough in overcoming tumor immune escape in NSCLC

Directory of Open Access Journals (Sweden)

He YY

2018-04-01

Full Text Available Yayi He,1,2,* Sangtian Liu,1,* Jane Mattei,3 Paul A Bunn Jr,2 Caicun Zhou,1 Daniel Chan2 1Department of Medical Oncology, Shanghai Pulmonary Hospital, Tongji University Medical School Cancer Institute, Tongji University School of Medicine, Shanghai, China; 2Division of Medical Oncology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, USA; 3Oncology Department, Moinhos de Vento Hospital, Porto Alegre, Brazil *These authors contributed equally to this work Background: The anti-programmed death-1 (PD-1/programmed death ligand-1 (PD-L1 monoclonal antibody has a good effect in the treatment of non-small cell lung cancer (NSCLC, but not all PD-1/PD-L1 positive patients can get benefit from it. Compensatory expression of other immune checkpoints may be correlated with the poor efficacy of anti-PD-1/PD-L1 monoclonal antibodies. The inhibitory human leukocyte antigen (HLA/killer cell Ig-like receptor (KIR can effectively block the killing effect of natural killer (NK cells on tumors. Our previous studies have confirmed that high expression of KIR was correlated with poor prognosis of NSCLC. Inhibitory KIR expression was positively correlated with the expression of PD-1. Methods: The expressions of KIR 2D (L1, L3, L4, S4 (BC032422/ADQ31987/NP_002246/NP_036446, Abcam and PD-1 (NAT 105, Cell marque proteins was assessed by immunohis­tochemistry. Results: The expression of inhibitory KIR in tumor cells or tumor infiltrating lymphocytes (TILs is associated with PD-1 expression. Among PD-1 positive patients, 76.3% were KIR 2D (L1, L3, L4, S4 positive on tumor cells, and 74.6% were KIR 2D (L1, L3, L4, S4 positive on TILs. We compared the expression of inhibitory KIR before and after treatment with nivolumab in 11 patients with NSCLC. We found that five (45.5% patients had positive expression of inhibitory KIR in tumor tissue after being treated with anti-PD-1 monoclonal antibodies, two of whom exhibited a significant

Demonstration of strong enterobacterial reactivity of CD4+CD25- T cells from conventional and germ-free mice which is counter-regulated by CD4+CD25+ T cells

DEFF Research Database (Denmark)

Gad, Monika; Pedersen, Anders Elm; Kristensen, Nanna N

2004-01-01

Unfractionated CD4+ T cells from the gut-associated lymphoid tissue (GALT) and peripheral lymph nodes are unresponsive when exposed to enterobacterial antigens in vitro. Under similar conditions, CD4+ T cells depleted in vivo or in vitro of CD4+CD25+ T cells proliferate extensively. The CD4+CD25- T...

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

Science.gov (United States)

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

2018-05-01

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

Radiolabeling of anti-CD20 with Re-188 for treatment of Non-Hodgkin's lymphoma: radiochemical control

International Nuclear Information System (INIS)

Dias, C.R.; Osso Junior, J.A.

2008-01-01

Radioimmunotherapy (RIT) uses target-specific monoclonal antibodies or fragments labeled with a radioactive isotope to combine humoral and radiolytic functions and has the advantage of targeting not only the cell to which the antibody is bound but also the surrounding tumor cells and microenvironment. The most successful clinical studies of RIT in patients with Non-Hodgkin's Lymphoma (NHL) have targeted CD20+ Bcell tumors. Antibody therapy directed against the CD20 antigen on the surface of B-cells is considered one of the first successful target-specific therapies in oncology. The radionuclide rhenium-188 ( 188 Re) is currently produced from the father nuclide 188 W through a transportable generator system. Because of its easy availability and suitable nuclear properties (E βMAX = 2.1 MeV, t1/2 = 16.9 h, E γ = 155 keV), this radionuclide is considered an attractive candidate for application as therapeutic agent and could be conveniently utilized for imaging and dosimetric purposes. The objective of this work is the optimization of direct radiolabeling method of anti-CD20 with 188 Re using a liquid formulation. Anti-CD20 was reduced by incubation with 2-mercaptoethanol at room temperature. The number of resulting free sulphydryl groups was assayed with Ellman's reagent. Optimization of radiolabeling was achieved by varying parameters: antibody mass, reducing agent mass, tartrate mass, stability and reaction time, 188 Re volume and activity. Radiochemical purity of 188 Re-anti-CD20 was evaluated using instant thin layer chromatography-silica gel (ITLC-SG). Quality control methods for evaluation of radiochemical purity showed good labeling yield of the antibody but further studies will be carried out in order to improve the labeling yields and consequently the specific activity of the product. (author)

Analyses of the peripheral immunome following multiple administrations of avelumab, a human IgG1 anti-PD-L1 monoclonal antibody.

Science.gov (United States)

Donahue, Renee N; Lepone, Lauren M; Grenga, Italia; Jochems, Caroline; Fantini, Massimo; Madan, Ravi A; Heery, Christopher R; Gulley, James L; Schlom, Jeffrey

2017-01-01

Multiple anti-PD-L1/PD-1 checkpoint monoclonal antibodies (MAb) have shown clear evidence of clinical benefit. All except one have been designed or engineered to omit the possibility to mediate antibody-dependent cell-mediated cytotoxicity (ADCC) as a second potential mode of anti-tumor activity; the reason for this is the concern of lysis of PD-L1 positive immune cells. Avelumab is a fully human IgG1 MAb which has been shown in prior in vitro studies to mediate ADCC versus a range of human tumor cells, and clinical studies have demonstrated anti-tumor activity versus a range of human cancers. This study was designed to investigate the effect on immune cell subsets in the peripheral blood of cancer patients prior to and following multiple administrations of avelumab. One hundred twenty-three distinct immune cell subsets in the peripheral blood of cancer patients ( n  = 28) in a phase I trial were analyzed by flow cytometry prior to and following one, three, and nine cycles of avelumab. Changes in soluble (s) CD27 and sCD40L in plasma were also evaluated. In vitro studies were also performed to determine if avelumab would mediate ADCC of PBMC. No statistically significant changes in any of the 123 immune cell subsets analyzed were observed at any dose level, or number of doses, of avelumab. Increases in the ratio of sCD27:sCD40L were observed, suggesting potential immune activation. Controlled in vitro studies also showed lysis of tumor cells by avelumab versus no lysis of PBMC from five donors. These studies demonstrate the lack of any significant effect on multiple immune cell subsets, even those expressing PD-L1, following multiple cycles of avelumab. These results complement prior studies showing anti-tumor effects of avelumab and comparable levels of adverse events with avelumab versus other anti-PD-1/PD-L1 MAbs. These studies provide the rationale to further exploit the potential ADCC mechanism of action of avelumab as well as other human IgG1 checkpoint

Cyclosporine therapy in inflammatory bowel disease: short-term and long-term results.

Science.gov (United States)

Gurudu, S R; Griffel, L H; Gialanella, R J; Das, K M

1999-09-01

Intravenous cyclosporine therapy followed by oral cyclosporine therapy reduce the need for urgent surgery in steroid-refractory inflammatory bowel disease (IBD). Our objective is to report short- and long-term results of cyclosporine therapy in IBD patients. Thirteen patients with steroid-refractory IBD, seven patients with ulcerative colitis (UC), and six patients with Crohn's disease (CD) were treated with intravenous cyclosporine (4 mg/kg/day) for a mean period of 11.4+/-2.8 days (range, 4-15 days). Subsequently the patients were started on oral cyclosporine (8 mg/kg/day) and followed for a mean of 10.3+/-10 months (range, 1-30 months). Twelve patients responded to intravenous cyclosporine therapy. One patient with UC developed sepsis on the fourth day of intravenous cyclosporine therapy and needed urgent colectomy. Nine of 12 initial responders (6 patients with UC and 3 patients with CD) relapsed during follow-up despite oral cyclosporine and underwent elective surgery. One patient with CD relapsed 3 months after discontinuation of oral cyclosporine. Only two patients with CD are in long-term remission. There were no long-term side effects in any of the 13 treated patients. In conclusion, intravenous cyclosporine was effective in inducing remission or significant improvement in 12 of 13 patients with steroid-refractory IBD. However, with subsequent oral cyclosporine the remission could be maintained only for a short while. Each of the six patients with UC needed colectomy and three of the five patients with CD had intestinal resection within 12 months despite oral cyclosporine therapy.

Clinical efficacy and management of monoclonal antibodies targeting CD38 and SLAMF7 in multiple myeloma

DEFF Research Database (Denmark)

van de Donk, Niels W C J; Moreau, Philippe; Plesner, Torben

2016-01-01

Immunotherapeutic strategies are emerging as promising therapeutic approaches in multiple myeloma (MM), with several monoclonal antibodies in advanced stages of clinical development. Of these agents, CD38-targeting antibodies have marked single agent activity in extensively pretreated MM...... of therapeutic antibodies with immunofixation and serum protein electrophoresis assays may lead to underestimation of complete response. Strategies to mitigate interference, based on shifting the therapeutic antibody band, are in development. Furthermore, daratumumab, and probably also other CD38-targeting...

Acute neurological worsening after Rituximab treatment in patients with anti-MAG neuropathy.

Science.gov (United States)

Sala, Emilie; Robert-Varvat, Florence; Paul, Stéphane; Camdessanché, Jean-Philippe; Antoine, Jean-Christophe

2014-10-15

Patients with peripheral neuropathy and anti-MAG monoclonal IgM may respond to Rituximab, a humanized monoclonal anti-CD20 antibody. We report on three patients with peripheral neuropathy and anti-MAG monoclonal IgM who deteriorated under Rituximab and reviewed seven previously published cases. Worsening was acute and severe, and occurred during the treatment period. All the patients improved after deterioration but at final evaluation only one was improved comparatively to baseline, five were worsened and four were stabilized. Deterioration was not clearly associated with an increase of the anti-MAG antibody titer. Two patients received Rituximab prior or after the course which induced worsening without adverse reaction. Although rare, acute worsening of the neuropathy can occur after Rituximab. The deterioration is however reversible within some weeks to several months. Copyright © 2014 Elsevier B.V. All rights reserved.

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

Energy Technology Data Exchange (ETDEWEB)

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

1995-10-01

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

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

International Nuclear Information System (INIS)

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

1995-01-01

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

An anti-CD3/anti-CLL-1 bispecific antibody for the treatment of acute myeloid leukemia.

Science.gov (United States)

Leong, Steven R; Sukumaran, Siddharth; Hristopoulos, Maria; Totpal, Klara; Stainton, Shannon; Lu, Elizabeth; Wong, Alfred; Tam, Lucinda; Newman, Robert; Vuillemenot, Brian R; Ellerman, Diego; Gu, Chen; Mathieu, Mary; Dennis, Mark S; Nguyen, Allen; Zheng, Bing; Zhang, Crystal; Lee, Genee; Chu, Yu-Waye; Prell, Rodney A; Lin, Kedan; Laing, Steven T; Polson, Andrew G

2017-02-02

Acute myeloid leukemia (AML) is a major unmet medical need. Most patients have poor long-term survival, and treatment has not significantly changed in 40 years. Recently, bispecific antibodies that redirect the cytotoxic activity of effector T cells by binding to CD3, the signaling component of the T-cell receptor, and a tumor target have shown clinical activity. Notably, blinatumomab is approved to treat relapsed/refractory acute lymphoid leukemia. Here we describe the design, discovery, pharmacologic activity, pharmacokinetics, and safety of a CD3 T cell-dependent bispecific (TDB) full-length human IgG1 therapeutic antibody targeting CLL-1 that could potentially be used in humans to treat AML. CLL-1 is prevalent in AML and, unlike other targets such as CD33 and CD123, is not expressed on hematopoietic stem cells providing potential hematopoietic recovery. We selected a high-affinity monkey cross-reactive anti-CLL-1 arm and tested several anti-CD3 arms that varied in affinity, and determined that the high-affinity CD3 arms were up to 100-fold more potent in vitro. However, in mouse models, the efficacy differences were less pronounced, probably because of prolonged exposure to TDB found with lower-affinity CD3 TDBs. In monkeys, assessment of safety and target cell depletion by the high- and low-affinity TDBs revealed that only the low-affinity CD3/CLL1 TDB was well tolerated and able to deplete target cells. Our data suggest that an appropriately engineered CLL-1 TDB could be effective in the treatment of AML. © 2017 by The American Society of Hematology.

Use of commercially available rabbit monoclonal antibodies for immunofluorescence double staining

DEFF Research Database (Denmark)

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

2008-01-01

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

Percentage and function of CD4+CD25+ regulatory T cells in patients with hyperthyroidism

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Jiang, Ting-Jun; Cao, Xue-Liang; Luan, Sha; Cui, Wan-Hui; Qiu, Si-Huang; Wang, Yi-Chao; Zhao, Chang-Jiu; Fu, Peng

2018-01-01

The current study observed the percentage of peripheral blood (PB) CD4+CD25+ regulatory T cells (Tregs) and the influence of CD4+CD25+ Tregs on the proliferation of naïve CD4 T cells in patients with hyperthyroidism. Furthermore, preliminary discussions are presented on the action mechanism of CD4+CD25+ Tregs on hyperthyroidism attacks. The present study identified that compared with the percentage of PB CD4+CD25+ Tregs in healthy control subjects, no significant changes were observed in the percentage of PB CD4+CD25+ Tregs in patients with hyperthyroidism (P>0.05). For patients with hyperthyroidism, CD4+CD25+ Tregs exhibited significantly reduced inhibition of the proliferation of naïve CD4 T cells and decreased secretion capacity on the cytokines of CD4 T cells, compared with those of healthy control subjects (Phyperthyroidism was significantly improved (Phyperthyroidism before treatment, no significant changes were observed in the percentage of PB CD4+CD25+ Tregs in hyperthyroidism patients following treatment (P>0.05). In the patients with hyperthyroidism, following treatment, CD4+CD25+ Tregs exhibited significantly increased inhibition of the proliferation of naïve CD4 T cells and increased secretion capacity of CD4 T cell cytokines, compared with those of the patients with hyperthyroidism prior to treatment (Phyperthyroidism, and its non-proportional decrease may be closely associated with the occurrence and progression of hyperthyroidism. PMID:29207121

Prevention of carrageenan-induced pleurisy in mice by anti-CD30 ligand monoclonal antibody

DEFF Research Database (Denmark)

Di Paola, Rosanna; Di Marco, Roberto; Mazzon, Emanuela

2004-01-01

CD30 ligand (CD30L) and its receptor CD30 are members of the tumor necrosis factor (TNF) and TNF receptor superfamilies that play a major role in inflammation and immune regulation. To gain insight into the in vivo role of CD30L/CD30 in inflammatory diseases, we have used carrageenan (CAR)-induce...

Effects of radiolabelled monoclonal antibody infusion on blood leukocytes in cancer patients

International Nuclear Information System (INIS)

Gridley, D.S.; Slater, J.M.; Stickney, D.R.

1990-01-01

This study was undertaken to investigate the effects of a single infusion of radiolabelled murine monoclonal antibody (MAb) on peripheral blood leukocytes in cancer patients. Eleven patients with disseminated colon cancer, malignant melanoma, or lung adenocarcinoma were infused with 111In-labelled anti-ZCE 025, anti-p97 type 96.5c, or LA 20207 MAb, respectively. Blood samples were obtained before infusion, immediately after infusion (1 hr), and at 4 and 7 days postinfusion. Flow cytometry analysis of CD3+, CD4+, CD8+, CD16+, and CD19+ lymphocytes showed increasing CD4:CD8 ratios in seven patients after infusion. This phenomenon was not restricted to antibody subclass or to type of cancer. Two of the remaining patients exhibited a marked post-infusion increase in CD8+ cells. In all three patients with malignant melanoma, decreasing levels of CD16+ lymphocytes were noted after infusion and natural killer cell cytotoxicity showed fluctuations which paralleled the changes in the CD16+ subpopulation. Oxygen radical production by phagocytic cells was markedly affected in three subjects. These results suggest that a single infusion of radiolabelled murine MAb may alter the balance of critical lymphocyte subpopulations and modulate other leukocyte responses in cancer patients

CD8{sup +}CD25{sup +} T cells reduce atherosclerosis in apoE(−/−) mice

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Zhou, Jianchang; Dimayuga, Paul C.; Zhao, Xiaoning; Yano, Juliana; Lio, Wai Man; Trinidad, Portia; Honjo, Tomoyuki; Cercek, Bojan; Shah, Prediman K.; Chyu, Kuang-Yuh, E-mail: Chyuk@cshs.org

2014-01-17

Highlights: •The role of a sub-population of CD8{sup +} T cells with suppressor functions was investigated in atherosclerosis. •CD8{sup +}CD25{sup +} T cells from adult apoE(−/−) mice had phenotype characteristics of T suppressor cells. •These CD8{sup +}CD25{sup +} T cells reduced CD4{sup +} T cell proliferation and CD8{sup +} cytotoxic activity in vitro. •Adoptive transfer of CD8{sup +}CD25{sup +} T cells significantly reduced atherosclerosis. •CD8{sup +}CD25{sup +} T cells have a suppressive function in atherosclerosis. -- Abstract: Background: It is increasingly evident that CD8{sup +} T cells are involved in atherosclerosis but the specific subtypes have yet to be defined. CD8{sup +}CD25{sup +} T cells exert suppressive effects on immune signaling and modulate experimental autoimmune disorders but their role in atherosclerosis remains to be determined. The phenotype and functional role of CD8{sup +}CD25{sup +} T cells in experimental atherosclerosis were investigated in this study. Methods and results: CD8{sup +}CD25{sup +} T cells were observed in atherosclerotic plaques of apoE(−/−) mice fed hypercholesterolemic diet. Characterization by flow cytometric analysis and functional evaluation using a CFSE-based proliferation assays revealed a suppressive phenotype and function of splenic CD8{sup +}CD25{sup +} T cells from apoE(−/−) mice. Depletion of CD8{sup +}CD25{sup +} from total CD8{sup +} T cells rendered higher cytolytic activity of the remaining CD8{sup +}CD25{sup −} T cells. Adoptive transfer of CD8{sup +}CD25{sup +} T cells into apoE(−/−) mice suppressed the proliferation of splenic CD4{sup +} T cells and significantly reduced atherosclerosis in recipient mice. Conclusions: Our study has identified an athero-protective role for CD8{sup +}CD25{sup +} T cells in experimental atherosclerosis.

CD4+ CD25+ CD127low Regulatory T Cells as Indicator of Rheumatoid Arthritis Disease Activity.

Science.gov (United States)

Khattab, Sahar S; El-Saied, Amany M; Mohammed, Rehab A; Mohamed, Eman E

2016-06-01

Rheumatoid arthritis (RA) is an autoimmune disease characterized by disturbed immune regulation, inducing a progressive cartilage and bone destruction. Despite enrichment of T regulatory cell (T-regs) in synovial fluid, conflicting results are reported concerning T-regs in peripheral blood (PB) of RA patients. To determine possible correlation between the frequency of PB CD4+ CD25+CD127low (T-regs) with RA disease activity. Forty females with RA, classified according to the Disease Activity Score 28 (DAS-28), as highly active, mild-moderate or low disease activity; and 20 age and sex matched healthy controls, were enrolled to study CD4+ CD25+ CD127low T- regs in PB by flow cytometry. Active RA patients had lower frequency of the CD4+ CD25+ CD127low T- regs compared to those with mild-moderate or low disease activity (P <0.001). The frequencies of the T- regs showed negative correlation with the DAS-28 (P<0.01). In conclusion, CD4+ CD25+ CD127low T-regs is significantly lower in highly active RA patients compared to patients with lower activity or controls. Copyright© by the Egyptian Association of Immunologists.

T CD3+CD8+ Lymphocytes Are More Susceptible for Apoptosis in the First Trimester of Normal Human Pregnancy

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Dorota Darmochwal-Kolarz

2014-01-01

Full Text Available Aims. Normal human pregnancy is a complex process of many immunoregulatory mechanisms which protect fetus from the activation of the maternal immune system. The aim of the study was to investigate the apoptosis of lymphocytes in peripheral blood of normal pregnant patients and healthy nonpregnant women. Methods. Sixty pregnant women and 17 nonpregnant women were included in the study. Lymphocytes were isolated and labeled with anti-CD3, anti-CD4, and anti-CD8 monoclonal antibodies. Apoptosis was detected by CMXRos staining and analyzed using the flow cytometric method. Results. We found significantly higher apoptosis of total lymphocytes in peripheral blood of pregnant patients when compared to healthy nonpregnant women. The percentage of apoptotic T CD3+CD8+ cells in the first trimester was significantly higher when compared to the third trimester of normal pregnancy. The ratio of T CD3+CD4+ : T CD3+CD8+ apoptotic lymphocytes was significantly lower in the first trimester when compared to other trimesters of pregnancy and to both of the phases of the menstrual cycle. Conclusions. The higher apoptosis of T CD3+CD8+ lymphocytes and the lower ratio of T CD3+CD4+ : T CD3+CD8+ apoptotic cells in the first trimester of normal pregnancy may suggest a higher susceptibility of T CD3+CD8+ cells for apoptosis as a protective mechanism at the early stage of pregnancy.

Preferential replication of FIV in activated CD4+CD25+T cells independent of cellular proliferation

International Nuclear Information System (INIS)

Joshi, Anjali; Vahlenkamp, Thomas W.; Garg, Himanshu; Tompkins, Wayne A.F.; Tompkins, Mary B.

2004-01-01

Studies attempting to identify reservoirs of HIV-1 latency have documented that the virus persists as both a latent and productive infection in subsets of CD4 + cells. Reports regarding establishment of a stable HIV-1 infection in quiescent T cells in vitro, however, are controversial. In the present study, we investigated the susceptibility of naive and activated CD4 + cell subsets (distinguished by differential expression of CD25) to feline immunodeficiency virus (FIV) infection, their ability to replicate the virus, and potentially act as a reservoir for virus persistence in infected animals. While both CD4 + CD25 + and CD4 + CD25 - cells are susceptible to FIV infection in vitro and in vivo, only CD4 + CD25 + cells produce infectious virions when cultured with interleukin-2 (IL-2). Latently infected CD4 + CD25 - cells produce infectious virions following ConcanvalinA (ConA) stimulation, which correlates with upregulated surface expression of CD25. In contrast to CD4 + CD25 - cells, CD4 + CD25 + cells remain unresponsive to mitogen stimulation and are relatively resistant to apoptosis whether or not infected with FIV. The ability of CD4 + CD25 + cells to replicate FIV efficiently in the presence of IL-2 but remain anergic and unresponsive to apoptotic signaling suggests that these cells may provide a reservoir of productive FIV infection. On the contrary, CD4 + CD25 - cells seem to establish as latent viral reservoirs capable of being reactivated after stimulation

A review of human anti-globulin antibody (HAGA, HAMA, HACA, HAHA) responses to monoclonal antibodies. Not four letter words.

Science.gov (United States)

Mirick, G R; Bradt, B M; Denardo, S J; Denardo, G L

2004-12-01

The United States Food and Drug Administration (FDA) has approved unconjugated monoclonal antibodies (MAbs) for immunotherapy (IT) of B-cell lymphoma, breast cancer and acute myeloid leukemia. More recently, approval has been given for conjugated ZevalinTM ((90)yttrium ibritumomab tiuxetan, IDEC-Y2B8, Biogen Idec, Cambridge, MA) and BexxarTM ((131)I-tositumomab, Corixa, Corp., Seattle, WA and GlaxoSmithKline, Philadelphia, PA) anti-CD20 MAbs for use in radioimmunotherapy (RIT) of non-Hodgkin's lymphoma (NHL), thus redefining the standard care of cancer patients. Because of, and despite a lack of basis for concern about allergic reactions due to human antibody responses to these foreign proteins, assays were developed to determine HAGA (human anti-globulin antibody) levels that developed in patient sera following treatment with MAbs. Strategies were also devised to ''humanize'' MAbs and to temporarily block patient immune function with drugs in order to decrease the seroconversion rates, with considerable success. On the other hand, a survival advantage has been observed in some patients who developed a HAGA following treatment. This correlates with development of an anti-idiotype antibody cascade directed toward the MAbs used to treat these patients. What follows is a selective review of HAGA and its effect on cancer treatment over the past 2 decades.

A review of human anti-globulin antibody (HAGA, HAMA, HACA, HAHA) responses to monoclonal antibodies. Not four letter words

International Nuclear Information System (INIS)

Mirick, G. R.; Bradt, B. M.; Denardo, S. J.; Denardo, G. L.

2004-01-01

The United States Food and Drugs Administration (FDA) has approved unconjugated monoclonal antibodies (MAbs) for immunotherapy (IT) of B-cell lymphoma, breast cancer and acute myeloid leukemia. More recently, approval has been given for conjugated ZevalinTM ( 9 0yttrium ibritumomab tiuxetan, IDEC-Y2B8, Biogen Idec, Cambridge, MA) and BexxarTM ( 1 31I-tositumomab, Corixa, Corp., Seattle, WA and GlaxoSmithKline, Philadelphia, PA) antiCD20 MAns for use in radioimmunotherapy (RIT) of non-Hodgikin's lymphoma (NHL), thus redefining the standard care of cancer patients. Because of, and despite a lack of basis for concern about allergic reactions due to human antibody responses to these foreign proteins, essays were developed to determine HAGE (human anti-globulin antibody) levels that developed in patient sera following treatment with MAbs. Strategies were also devised to humanize MAbs and to temporarily block patient immune function with drugs in order to decrease the seroconversion rates, with considerable success. On the other hand, a survival advantage has been observed in some patients who developed a HAGA following treatment. This correlates with development of an anti-idiotype antibody cascade directed toward the MAbs used to treat these patients. What follows is a selective review of HAGA and its effect on cancer treatment over the past 2 decades

Immunotherapy of Alzheimer's disease (AD): from murine models to anti-amyloid beta (Abeta) human monoclonal antibodies.

Science.gov (United States)

Geylis, Valeria; Steinitz, Michael

2006-01-01

The deposition of amyloid beta (Abeta) protein is a key pathological feature in Alzheimer's disease (AD). In murine models of AD, both active and passive immunization against Abeta induce a marked reduction in amyloid brain burden and an improvement in cognitive functions. Preliminary results of a prematurely terminated clinical trial where AD patients were actively vaccinated with aggregated Abeta bear resemblance to those documented in murine models. Passive immunization of AD patients with anti-Abeta antibodies, in particular human antibodies, is a strategy that provides a more cautious management and control of any undesired side effects. Sera of all healthy adults contain anti-Abeta IgG autoimmune antibodies. Hence antigen-committed human B-cells are easily immortalized by Epstein-Barr virus (EBV) into anti-Abeta secreting cell lines. Two anti-Abeta human monoclonal antibodies which we recently prepared bind to the N-terminus of Abeta peptide and were shown to stain amyloid plaques in non-fixed brain sections from an AD patient. It is anticipated that specifically selected anti-Abeta human monoclonal antibodies could reduce and inhibit deposits of amyloid in brain while avoiding the cognitive decline that characterizes AD. In the future, this type of antibody may prove to be a promising immune therapy for the disease.

CD4+CD25+ T regulatory cells from FIV+ cats induce a unique anergic profile in CD8+ lymphocyte targets

Directory of Open Access Journals (Sweden)

Tompkins Mary B

2010-11-01

Full Text Available Abstract Background Using the FIV model, we reported previously that CD4+CD25+ T regulatory (Treg cells from FIV+ cats are constitutively activated and suppress CD4+CD25- and CD8+ T cell immune responses. In an effort to further explore Treg-mediated suppression, we asked whether Treg cells induce anergy through the alteration of production of cyclins, cyclin-dependent kinases and their inhibitors. Results Lymphocytes were obtained from control or FIV+ cats and sorted by FACS into CD4+CD25+ and CD8+ populations. Following co-culture with CD4+CD25+ cells, CD8+ targets were examined by Western blot for changes in cyclins D3, E and A, retinoblastoma (Rb protein, as well as the cyclin dependent kinase inhibitor p21cip1. Following co-culture with CD4+CD25+cells, we observed up-regulation of p21cip1 and cyclin E, with down-regulation of cyclin D3, in CD8+ cells from FIV+ cats. As expected, CD8+ targets from control cats were quiescent with little up-regulation of p21cip1 and cyclin E. There was also a lack of Rb phosphorylation in CD8+ targets consistent with late G1 cell cycle arrest. Further, IL-2 mRNA was down regulated in CD8+ cells after co-culture with CD4+CD25+ Treg cells. Following CD4+CD25+ co-culture, CD8+ targets from FIV+ cats also had increased Foxp3 mRNA expression; however, these CD8+Foxp3+ cells did not exhibit suppressor function. Conclusions Collectively, these data suggest that CD4+CD25+ Treg cells from FIV+ cats induce CD8+ anergy by disruption of normal G1 to S cell cycle progression.

Nebulized Anti-IL-13 Monoclonal Antibody Fab' Fragment Reduces Allergen-Induced Asthma

OpenAIRE

Hacha, Jonathan; Tomlinson, K; Maertens, Ludovic; Paulissen, Geneviève; Rocks, Natacha; Foidart, Jean-Michel; Noël, Agnès; Palframan, R; Guéders, Maud; Cataldo, Didier

2012-01-01

Rationale: Interleukin-13 (IL-13) is a prototypic Th2 cytokine and a central mediator of the complex cascade of events leading to asthmatic phenotype. Indeed, IL-13 plays key roles in IgE synthesis, bronchial hyperresponsiveness, mucus hypersecretion, subepithelial fibrosis and eosinophil infiltration. Objectives: We assessed the potential efficacy of inhaled anti-IL-13 monoclonal antibody Fab' fragment on allergen-induced airway inflammation, hyperresponsiveness and remodeling in an experime...

A novel anti-GPC3 monoclonal antibody (YP7) | Center for Cancer Research

Science.gov (United States)

Glypican-3 (GPC3) is an emerging therapeutic target in hepatoma. A novel anti-GPC3 monoclonal antibody (YP7) has been generated through a combination of peptide immunization and high-throughput flow cytometry screening. YP7 binds cell-surface-associated GPC3 with high affinity and exhibits significant hepatoma xenograft growth inhibition in nude mice. The new antibody may have

Evaluation of a brief anti-stigma campaign in Cambridge: do short-term campaigns work?

Science.gov (United States)

Evans-Lacko, Sara; London, Jillian; Little, Kirsty; Henderson, Claire; Thornicroft, Graham

2010-06-14

In view of the high costs of mass-media campaigns, it is important to understand whether it is possible for a media campaign to have significant population effects over a short period of time. This paper explores this question specifically in reference to stigma and discrimination against people with mental health problems using the Time to Change Cambridge anti-stigma campaign as an example. 410 face-to-face interviews were performed pre, during and post campaign activity to assess campaign awareness and mental health-related knowledge, attitudes and behaviours. Although campaign awareness was not sustained following campaign activity, significant and sustained shifts occurred for mental health-related knowledge items. Specifically, there was a 24% (p mental health problem, I know what advice to give them to get professional help, following the campaign. Additionally, for the statement: Medication can be an effective treatment for people with mental health problems, there was a 10% rise (p = 0.05) in the proportion of interviewees responding 'agree' or 'strongly agree' following the campaign. These changes, however, were not evident for attitudinal or behaviour related questions. Although these results only reflect the impact of one small scale campaign, these preliminary findings suggest several considerations for mass-media campaign development and evaluation strategies such as: (1) Aiming to influence outcomes pertaining to knowledge in the short term; (2) Planning realistic and targeted outcomes over the short, medium and long term during sustained campaigns; and (3) Monitoring indirect campaign effects such as social discourse or other social networking/contact in the evaluation.

Detection of Signal Regulatory Protein α in Saimiri sciureus (Squirrel Monkey) by Anti-Human Monoclonal Antibody

Science.gov (United States)

de Souza, Hugo Amorim dos Santos; Costa-Correa, Edmar Henrique; Bianco-Junior, Cesare; Andrade, Márcia Cristina Ribeiro; Lima-Junior, Josué da Costa; Pratt-Riccio, Lilian Rose; Daniel-Ribeiro, Cláudio Tadeu; Totino, Paulo Renato Rivas

2017-01-01

Non-human primates (NHP) are suitable models for studying different aspects of the human system, including pathogenesis and protective immunity to many diseases. However, the lack of specific immunological reagents for neo-tropical monkeys, such as Saimiri sciureus, is still a major factor limiting studies in these models. An alternative strategy to circumvent this obstacle has been the selection of immunological reagents directed to humans, which present cross-reactivity with NHP molecules. In this context and considering the key role of inhibitory immunoreceptors—such as the signal regulatory protein α (SIRPα)—in the regulation of immune responses, in the present study, we attempted to evaluate the ability of anti-human SIRPα monoclonal antibodies to recognize SIRPα in antigen-presenting S. sciureus peripheral blood mononuclear cells (PBMC). As shown by flow cytometry analysis, the profile of anti-SIRPα staining as well as the levels of SIRPα-positive cells in PBMC from S. sciureus were similar to those observed in human PBMC. Furthermore, using anti-SIRPα monoclonal antibody, it was possible to detect a decrease of the SIRPα levels on surface of S. sciureus cells after in vitro stimulation with lipopolysaccharides. Finally, using computed-based analysis, we observed a high degree of conservation of SIRPα across six species of primates and the presence of shared epitopes in the extracellular domain between humans and Saimiri genus that could be targeted by antibodies. In conclusion, we have identified a commercially available anti-human monoclonal antibody that is able to detect SIRPα of S. sciureus monkeys and that, therefore, can facilitate the study of the immunomodulatory role of SIRPα when S. sciureus is used as a model. PMID:29312325

Detection of Signal Regulatory Protein α in Saimiri sciureus (Squirrel Monkey by Anti-Human Monoclonal Antibody

Directory of Open Access Journals (Sweden)

Hugo Amorim dos Santos de Souza

2017-12-01

Full Text Available Non-human primates (NHP are suitable models for studying different aspects of the human system, including pathogenesis and protective immunity to many diseases. However, the lack of specific immunological reagents for neo-tropical monkeys, such as Saimiri sciureus, is still a major factor limiting studies in these models. An alternative strategy to circumvent this obstacle has been the selection of immunological reagents directed to humans, which present cross-reactivity with NHP molecules. In this context and considering the key role of inhibitory immunoreceptors—such as the signal regulatory protein α (SIRPα—in the regulation of immune responses, in the present study, we attempted to evaluate the ability of anti-human SIRPα monoclonal antibodies to recognize SIRPα in antigen-presenting S. sciureus peripheral blood mononuclear cells (PBMC. As shown by flow cytometry analysis, the profile of anti-SIRPα staining as well as the levels of SIRPα-positive cells in PBMC from S. sciureus were similar to those observed in human PBMC. Furthermore, using anti-SIRPα monoclonal antibody, it was possible to detect a decrease of the SIRPα levels on surface of S. sciureus cells after in vitro stimulation with lipopolysaccharides. Finally, using computed-based analysis, we observed a high degree of conservation of SIRPα across six species of primates and the presence of shared epitopes in the extracellular domain between humans and Saimiri genus that could be targeted by antibodies. In conclusion, we have identified a commercially available anti-human monoclonal antibody that is able to detect SIRPα of S. sciureus monkeys and that, therefore, can facilitate the study of the immunomodulatory role of SIRPα when S. sciureus is used as a model.

CD99 at the crossroads of physiology and pathology.

Science.gov (United States)

Pasello, Michela; Manara, Maria Cristina; Scotlandi, Katia

2018-03-01

CD99 is a cell surface protein with unique features and only partly defined mechanisms of action. This molecule is involved in crucial biological processes, including cell adhesion, migration, death, differentiation and diapedesis, and it influences processes associated with inflammation, immune responses and cancer. CD99 is frequently overexpressed in many types of tumors, particularly pediatric tumors including Ewing sarcoma and specific subtypes of leukemia. Engagement of CD99 induces the death of malignant cells through non-conventional mechanisms. In Ewing sarcoma, triggering of CD99 by specific monoclonal antibodies activates hyperstimulation of micropinocytosis and leads to cancer cells killing through a caspase-independent, non-apoptotic pathway resembling methuosis. This process is characterized by extreme accumulation of vacuoles in the cytoplasmic space, which compromises cell viability, requires the activation of RAS-Rac1 downstream signaling and appears to be rather specific for tumor cells. In addition, anti-CD99 monoclonal antibodies exhibit antitumor activities in xenografts in the absence of immune effector cells or complement proteins. Overall, these data establish CD99 as a new opportunity to treat patients with high expression of CD99, particularly those that are resistant to canonical apoptosis-inducing agents.

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

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Ceran Ceyhan

2012-10-01

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

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

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Stefan Ryser

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

Correlation between CD105 expression and postoperative recurrence and metastasis of hepatocellular carcinoma

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Wang Wei

2006-05-01

Full Text Available Abstract Background Angiogenesis is one of the mechanisms most critical to the postoperative recurrence and metastasis of hepatocellular carcinoma (HCC. Thus, finding the molecular markers associated with angiogenesis may help identify patients at increased risk for recurrence and metastasis of HCC. This study was designed to investigate whether CD105 or CD34 could serve as a valid prognostic marker in patients with HCC by determining if there is a correlation between CD105 or CD34 expression and postoperative recurrence or metastasis. Methods Immunohistochemical staining for the CD105, CD34 and vascular endothelial growth factor (VEGF antibodies was performed in 113 HCC tissue specimens containing paracarcinomatous tissue and in 14 normal liver tissue specimens. The quantitation of microvessels identified by anti-CD105 and anti-CD34 monoclonal antibodies and the semiquantitation of VEGF expression identified by anti-VEGF monoclonal antibody were analyzed in conjunction with the clinicopathological characteristics of the HCC and any available follow-up information about the patients from whom the specimens were obtained. Results CD105 was not expressed in the vascular endothelial cells of any normal liver tissue or paracarcinomatous liver tissue but was expressed in the vascular endothelial cells of all HCC tissue. In contrast, CD34 was expressed in the vascular endothelial cells of normal liver tissue, paracarcinomatous tissue, and HCC tissue in the following proportions of specimens: 86.7%, 93.8%, and 100%, respectively. The microvascular densities (MVDs of HCC determined by using an anti-CD105 mAb (CD105-MVD and an anti-CD34 mAb (CD34-MVD, were 71.7 ± 8.3 (SD and 106.3 ± 10.4 (SD, respectively. There was a significant correlation between CD105-MVD and CD34-MVD (r = 0.248, P = 0.021. Although CD34-MVD was significantly correlated with VEGF expression (r = 0.243, P = 0.024, CD105-MVD was more closely correlated (r = 0.300, P= 0.005. The

Characterization of the Anti-Bovine Podoplanin Monoclonal Antibody PMab-44.

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Yamada, Shinji; Honma, Ryusuke; Kaneko, Mika K; Nakamura, Takuro; Yanaka, Miyuki; Saidoh, Noriko; Takagi, Michiaki; Konnai, Satoru; Kato, Yukinari

2017-06-01

A type I transmembrane sialoglycoprotein podoplanin (PDPN) is expressed in several normal cells, including podocytes of the kidney, type I alveolar cells of the lung, and lymphatic endothelial cells. We recently produced an anti-bovine PDPN (bovPDPN) monoclonal antibody (mAb), PMab-44, by immunizing mice with recombinant proteins of bovPDPN. In this study, we determined the critical epitope of PMab-44 for the recognition of bovPDPN using many deletion mutants and point mutants of bovPDPN. Flow cytometric analyses revealed that the epitope of PMab-44 was Glu46-Thr50, which corresponds to platelet aggregation-stimulating (PLAG) domain-3. The important amino acids in the PMab-44 epitope were determined to be Glu46, Tyr48, and Thr50. Western blot analysis also confirmed these results, indicating that the PLAG domain of bovPDPN is also important in immunogenicity for producing useful anti-PDPN mAbs.

Short-term Treatment of Daumone Improves Hepatic Inflammation in Aged Mice.

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Park, Jong Hee; Ha, Hunjoo

2015-05-01

Chronic inflammation has been proposed as one of the main molecular mechanisms of aging and age-related diseases. Although evidence in humans is limited, short-term calorie restriction (CR) has been shown to have anti-inflammatory effects in aged experimental animals. We reported on the long-term treatment of daumone, a synthetic pheromone secreted by Caenorhabditis elegans in an energy deficient environment, extends the life-span and attenuates liver injury in aged mice. The present study examined whether late onset short-term treatment of daumone exerts anti-inflammatory effects in the livers of aged mice. Daumone was administered orally at doses of 2 or 20 mg/kg/day for 5 weeks to 24-month-old male C57BL/6J mice. Increased liver macrophage infiltration and gene expression of proinflammatory cytokines in aged mice were significantly attenuated by daumone treatment, suggesting that short-term oral administration of daumone may have hepatoprotective effects. Daumone also dose-dependently suppressed tumor necrosis factor-α (TNF-α)-induced nuclear factor-κB (NF-κB) phosphorylation in HepG2 cells. The present data demonstrated that short-term treatment of daumone has anti-inflammatory effects in aged mouse livers possibly through suppression of NF-κB signaling and suggest that daumone may become a lead compound targeting aging and age-associated diseases.

Stability and electronic properties of Cd0.75Mn0.25S and Cd0.75Mn0.25Se in B3 phase

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Rani, Anita [Guru Nanak College for Girls, Sri Muktsar Sahib, Punjab (India); Kumar, Ranjan [Panjab University, Department of Physics, Chandigarh (India)

2015-08-15

We studied the structural, elastic, spin-polarized electronic band structures and magnetic properties of the diluted magnetic semiconductor Cd{sub 1-x}Mn{sub x}S and Cd{sub 1-x} Mn{sub x}Se in zinc blende phase (B3) for x = 0.25 using ab initio method. The calculations were performed by using density functional theory as implemented in the Spanish Initiative for Electronic Simulations with Thousands of Atoms code using local density approximation. Calculated electronic band structures and magnetic properties of Cd{sub 1-x}Mn{sub x}S are discussed in terms of contribution of Mn 3d{sup 5} 4s{sup 2}, Cd 4d{sup 10} 5s{sup 2}, S 3s{sup 2} 3p{sup 4} orbitals. The total magnetic moment is found to be 5.00 μ{sub b} for Cd{sub 1-x}Mn{sub x}S and Cd{sub 1-x}Mn{sub x}Se at x = 0.25. This value indicates that Mn atom adds no hole carrier to the perfect CdS crystal. We determine the spin-exchange splitting energies produced by Mn 3d states, s-d exchange constant N{sub 0}α, and p-d exchange constant N{sub 0}β. We found that Mn-doped systems are ferromagnetic. Calculated results are in good agreement with previous studies. (orig.)

Downregulation of IL-12 and a novel negative feedback system mediated by CD25+CD4+ T cells

International Nuclear Information System (INIS)

Sato, Kojiro; Tateishi, Shoko; Kubo, Kanae; Mimura, Toshihide; Yamamoto, Kazuhiko; Kanda, Hiroko

2005-01-01

CD25 + CD4 + regulatory T cells suppress immune responses and are believed to play roles in preventing autoimmune diseases. However, the mechanism(s) underlying the suppression and the regulation of their homeostasis remain to be elucidated. Here we show that these regulatory T cells downregulated CD25 - CD4 + T-cell-mediated production of IL-12 from antigen-presenting cells, which can act as a growth factor for CD25 - CD4 + T cells. We further found that CD25 + CD4 + T cells, despite their well-documented 'anergic' nature, proliferate significantly in vitro only when CD25 - CD4 + T cells are present. Notably, this proliferation was strongly dependent on IL-2 and relatively independent of IL-12. Thus, CD25 + CD4 + T cells suppress CD25 - CD4 + T-cell responses, at least in part, by inhibiting IL-12 production while they themselves can undergo proliferation with the mediation of CD25 - CD4 + T cells in vitro. These results offer a novel negative feedback system involving a tripartite interaction among CD25 + CD4 + and CD25 - CD4 + T cells, and APCs that may contribute to the termination of immune responses

Clinical Trials Using Anti-CD19/CD28/CD3zeta CAR Gammaretroviral Vector-transduced Autologous T Lymphocytes KTE-C19

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NCI supports clinical trials that test new and more effective ways to treat cancer. Find clinical trials studying anti-cd19/cd28/cd3zeta car gammaretroviral vector-transduced autologous t lymphocytes kte-c19.

A role for CD4+ but not CD8+ T cells in immunity to Schistosoma mansoni induced by 20 krad-irradiated and Ro 11-3128-terminated infections

International Nuclear Information System (INIS)

Vignali, D.A.A.; Bickle, Q.D.; Taylor, M.G.; Crocker, P.; Cobbold, S.; Waldmann, H

1989-01-01

The role of CD4 + (L3/T4 + ) and CD8 + (Lyt-2 + ) T cells in immunity to Schistosoma mansoni induced by 20 krad-irradiated and Ro 11-terminated infections in mice was investigated directly by in vivo depletion of these subsets with cytotoxic rat monoclonal antibodies (mAb). Effective physical depletion was demonstrated by flow cytometric analysis and immunohistochemical staining. Functional depletion of helper activity following anti-CD4 treatment was indicated by an abrogation of concanavalin A(Con A)-induced colony-stimulating factor (CSF) release, while anti-CD8 treatment had no effect in these assays. Pre-existing S. mansoni-specific antibody levels were unaffected by anti-CD4 and anti-CD8 treatment. In vivo depletion of CD4 + T cells resulted in a dramatic reduction in immunity induced by one (up to 100%) and two (up to 70%) vaccinations with 20 krad-irradiated cercariae and also of resistance induced by Ro 11-attenuated infections (up to 100%). Depletion of CD8 + T cells had no effect on resistance induced by any of the vaccination protocols investigated. A correlation was observed between resistance and T cell-induced, macrophage-mediated killing of schistosomula in vitro, both of which were abrogated following anti-CD4 treatment but were unaffected by CD8 + T-cell depletion. The possible role of CD4 + T cells in vivo and the implications for vaccine development are discussed. (author)

Evaluation of a brief anti-stigma campaign in Cambridge: do short-term campaigns work?

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Henderson Claire

2010-06-01

Full Text Available Abstract Background In view of the high costs of mass-media campaigns, it is important to understand whether it is possible for a media campaign to have significant population effects over a short period of time. This paper explores this question specifically in reference to stigma and discrimination against people with mental health problems using the Time to Change Cambridge anti-stigma campaign as an example. Methods 410 face-to-face interviews were performed pre, during and post campaign activity to assess campaign awareness and mental health-related knowledge, attitudes and behaviours. Results Although campaign awareness was not sustained following campaign activity, significant and sustained shifts occurred for mental health-related knowledge items. Specifically, there was a 24% (p If a friend had a mental health problem, I know what advice to give them to get professional help, following the campaign. Additionally, for the statement: Medication can be an effective treatment for people with mental health problems, there was a 10% rise (p = 0.05 in the proportion of interviewees responding 'agree' or 'strongly agree' following the campaign. These changes, however, were not evident for attitudinal or behaviour related questions. Conclusions Although these results only reflect the impact of one small scale campaign, these preliminary findings suggest several considerations for mass-media campaign development and evaluation strategies such as: (1 Aiming to influence outcomes pertaining to knowledge in the short term; (2 Planning realistic and targeted outcomes over the short, medium and long term during sustained campaigns; and (3 Monitoring indirect campaign effects such as social discourse or other social networking/contact in the evaluation.

A review of human anti-globulin antibody (HAGA, HAMA, HACA, HAHA) responses to monoclonal antibodies. Not four letter words

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Mirick, G. R.; Bradt, B. M.; Denardo, S. J.; Denardo, G. L. [Calfornia Univ., Sacramento (United States). Davis Medical Center

2004-12-01

The United States Food and Drugs Administration (FDA) has approved unconjugated monoclonal antibodies (MAbs) for immunotherapy (IT) of B-cell lymphoma, breast cancer and acute myeloid leukemia. More recently, approval has been given for conjugated ZevalinTM ({sup 9}0yttrium ibritumomab tiuxetan, IDEC-Y2B8, Biogen Idec, Cambridge, MA) and BexxarTM ({sup 1}31I-tositumomab, Corixa, Corp., Seattle, WA and GlaxoSmithKline, Philadelphia, PA) antiCD20 MAns for use in radioimmunotherapy (RIT) of non-Hodgikin's lymphoma (NHL), thus redefining the standard care of cancer patients. Because of, and despite a lack of basis for concern about allergic reactions due to human antibody responses to these foreign proteins, essays were developed to determine HAGE (human anti-globulin antibody) levels that developed in patient sera following treatment with MAbs. Strategies were also devised to humanize MAbs and to temporarily block patient immune function with drugs in order to decrease the seroconversion rates, with considerable success. On the other hand, a survival advantage has been observed in some patients who developed a HAGA following treatment. This correlates with development of an anti-idiotype antibody cascade directed toward the MAbs used to treat these patients. What follows is a selective review of HAGA and its effect on cancer treatment over the past 2 decades.

Immunoscintigraphy of human tumors transplanted in nude mice with radiolabeled anti-ras p21 monoclonal antibodies

International Nuclear Information System (INIS)

Katoh, Y.; Nakata, K.; Kohno, K.; Shima, M.; Satoh, A.; Kusumoto, Y.; Ishii, N.; Kohji, T.; Shiku, H.; Nagataki, S.

1990-01-01

Anti-ras p21 monoclonal antibody (RASK-3) was used for immunoscintigraphy of human cancer cell lines in nude mice. Iodine-125-labeled RASK-3 was injected into nude mice with either human colon cancers (FCC-1 or BM-314) or lung cancer (KNS-62). Clear images were obtained in all three cancers 7 days after the injection of antibody. No localization of 125 I-labeled control monoclonal antibody was observed. The ratio of tissue/blood radioactivity and % ID/g in the tumor were significantly higher than other organs by Day 8. The specific localization index examined by 131 I-RASK-3 and 125 I-control monoclonal antibody was also higher in the tumor than in other tissues. In the in vitro study, binding of RASK-3 to tumor cells increased significantly by treatment of cells with either lysolecithin or periodate-lysine-paraformaldehyde, which confirmed the intracellular localization of ras p21. The mechanism by which anti-ras p21 antibodies accumulate in tumor sites could be the necrotic changes in tumor cells or changes in membrane permeability of non-necrotic cells. These results provide a strong rationale for the utilization of ras p21 as a target antigen in the imaging of a variety of human cancers

Construction and characterization of an anti-CD20 mAb nanocomb with exceptionally excellent lymphoma-suppressing activity

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Li H

2015-07-01

Full Text Available Hua-Fei Li,1–3,* Cong Wu,4,* Ting Chen,5,* Ge Zhang,1 He Zhao,1 Chang-Hong Ke,1 Zheng Xu21International Joint Cancer Institute, Translation Medicine Institute, 2Planning Division, Scientific Research Department, 3Tumor Immunology and Gene Therapy Center, Eastern Hepatobiliary Surgery Hospital, 4Department of Laboratory Diagnosis, Changhai Hospital, 5Department of Cardiology, Changhai Hospital, the Second Military Medical University, Shanghai, People’s Republic of China *These authors contributed equally to this work Abstract: The CD20-directed monoclonal antibody rituximab (RTX established a new era in the treatment of non-Hodgkin lymphoma (NHL; however, suboptimal response and/or resistance to RTX still limit its clinical merits. Although four effector mechanisms are validated to participate in CD20-based immunotherapy, including complement-dependent cytotoxicity, antibody-dependent cell-mediated cytotoxicity, caspase-dependent apoptosis, and lysosome-mediated programmed cell death (PCD, they could hardly be synchronously activated by any anti-CD20 mAb or mAb derivative until now. Herein, a novel mAb nanocomb (polyethylenimine polymer–RTX–tositumomab [PPRT nanocomb] was firstly constructed through mass arming two different anti-CD20 mAbs (RTX and tositumomab to one polymer by nanotechnology. Comparing with free mAbs, PPRT nanocomb possesses a comparable binding ability and reduced “off-rate” to surface CD20 of NHL cells. When treated by PPRT nanocomb, the caspase-dependent apoptosis was remarkably enhanced except for concurrently eliciting complement-dependent cytotoxicity, antibody-dependent cell-mediated cytotoxicity, and lysosome-mediated PCD. Besides, “cross-cell link”-assisted homotypic adhesion by PPRT nanocomb further enhanced the susceptibility to PCD of lymphoma cells. Pharmacokinetic assays revealed that PPRT nanocomb experienced a relatively reduced clearance from peripheral blood compared with free antibodies. With

Phenotypic and Functional Characterization of Monoclonal Antibodies with Specificity for Rhesus Macaque CD200, CD200R and Mincle.

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Siddappa N Byrareddy

Full Text Available Lectin-like molecules and their receptors are cell surface molecules that have been shown to play a role in either facilitating infection or serving as transporters of HIV/SIV in vivo. The role of these lectin-like molecules in the pathogenesis of HIV/SIV infection continues to be defined. In efforts to gain further insight on the potential role of these lectin-like molecules, our laboratory generated monoclonal antibodies (mAb against the human analogs of rhesus macaque CD200, CD200R and Mincle, since the rhesus macaques are accepted as the most reliable animal model to study human HIV infection. The characterization of the cell lineages from the blood and various tissues of rhesus macaques that express these lectin-like molecules are described herein. Among the mononuclear cells, the cells of the myeloid lineage of rhesus macaques are the predominant cell lineages that express readily detectable levels of CD200, CD200R and Mincle that is similar to the expression of Siglec-1 and Siglec-3 reported by our laboratory earlier. Subset analysis revealed that a higher frequency of the CD14+/CD16- subset from normal rhesus macaques express CD200, CD200R and Mincle. Differences in the frequencies and density of expression of these molecules by the gated population of CD14+ cells from various tissues are noted with PBMC and bone marrow expressing the highest and the mononuclear cells isolated from the colon and ileum expressing the lowest levels. While a significant frequency of pDCs and mDCs express Siglec-1/Siglec-3, a much lower frequency expresses CD200, CD200R and Mincle in PBMCs from rhesus macaques. The mAb against CD200 and CD200R but not Mincle appear to inhibit the infection of macrophage tropic SIV/SHIV in vitro. We conclude that these mAbs may have potential to be used as adjunctive therapeutic agents to control/inhibit SIV/HIV infection.

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

NARCIS (Netherlands)

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

2004-01-01

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

25 CFR 26.30 - Does the Job Training Program provide part-time training or short-term training?

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2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false Does the Job Training Program provide part-time training or short-term training? 26.30 Section 26.30 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR HUMAN SERVICES JOB PLACEMENT AND TRAINING PROGRAM Training Services § 26.30 Does the Job Training...

Non-traditional CD4+CD25-CD69+ regulatory T cells are correlated to leukemia relapse after allogeneic hematopoietic stem cell transplantation.

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Zhao, Xiao-su; Wang, Xu-hua; Zhao, Xiang-yu; Chang, Ying-jun; Xu, Lan-ping; Zhang, Xiao-hui; Huang, Xiao-jun

2014-07-01

Non-traditional CD4+CD25-CD69+ T cells were found to be involved in disease progression in tumor-bearing mouse models and cancer patients recently. We attempted to define whether this subset of T cells were related to leukemia relapse after allogeneic hematopoietic cell transplantation (allo-HSCT). The frequency of CD4+CD25-CD69+ T cells among the CD4+ T cell population from the bone marrow of relapsed patients, patients with positive minimal residual disease (MRD+) and healthy donors was examined by flow cytometry. The CD4+CD25-CD69+ T cells were also stained with the intracellular markers to determine the cytokine (TGF-β, IL-2 and IL-10) secretion. The results showed that the frequency of CD4+CD25-CD69 + T cells was markedly increased in patients in the relapsed group and the MRD + group compared to the healthy donor group. The percentage of this subset of T cells was significantly decreased after effective intervention treatment. We also analyzed the reconstitution of CD4+CD25-CD69+ T cells at various time points after allo-HSCT, and the results showed that this subset of T cells reconstituted rapidly and reached a relatively higher level at +60 d in patients compared to controls. The incidence of either MRD+ or relapse in patients with a high frequency of CD4+CD25-CD69+ T cells (>7%) was significantly higher than that of patients with a low frequency of CD4+CD25-CD69+ T cells at +60 d, +90 d and +270 d after transplant. However, our preliminary data indicated that CD4+CD25-CD69+ T cells may not exert immunoregulatory function via cytokine secretion. This study provides the first clinical evidence of a correlation between non-traditional CD4+CD25-CD69+ Tregs and leukemia relapse after allo-HSCT and suggests that exploration of new methods of adoptive immunotherapy may be beneficial. Further research related to regulatory mechanism behind this phenomenon would be necessary.

Monoclonal Antibodies for Non-Hodgkin's Lymphoma: State of the Art and Perspectives

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Giulia Motta

2010-01-01

Full Text Available Monoclonal antibodies have been the most successful therapeutics ever brought to cancer treatment by immune technologies. The use of monoclonal antibodies in B-cell Non-Hodgkin's lymphomas (NHL represents the greatest example of these advances, as the introduction of the anti-CD20 antibody rituximab has had a dramatic impact on how we treat this group of diseases today. Despite this success, several questions about how to optimize the use of monoclonal antibodies in NHL remain open. The best administration schedules, as well as the optimal duration of rituximab treatment, have yet to be determined. A deeper knowledge of the mechanisms underlying resistance to rituximab is also necessary in order to improve the activity of this and of similar therapeutics. Finally, new antibodies and biological agents are entering the scene and their advantages over rituximab will have to be assessed. We will discuss these issues and present an overview of the most significant clinical studies with monoclonal antibodies for NHL treatment carried out to date.

Generation, characterization and in vivo biological activity of two distinct monoclonal anti-PEG IgMs

International Nuclear Information System (INIS)

Hashimoto, Yosuke; Shimizu, Taro; Mima, Yu; Abu Lila, Amr S.; Ishida, Tatsuhiro; Kiwada, Hiroshi

2014-01-01

PEGylation, the attachment of polyethylene glycol (PEG) to nanocarriers and proteins, is a widely accepted approach to improving the in vivo efficacy of the non-PEGylated products. However, both PEGylated liposomes and PEGylated proteins reportedly trigger the production of specific antibodies, mainly IgM, against the PEG moiety, which possibly leads to a reduction in safety and therapeutic efficacy of the PEGylated products. In the present study, two monoclonal anti-PEG IgMs — HIK-M09 via immunization with an intravenous injection of PEGylated liposomes (SLs) and HIK-M11 via immunization with a subcutaneous administration of PEGylated ovalbumin (PEG-OVA) were successfully generated. The generated IgMs showed efficient reactivity to mPEG 2000 conjugated to 1,2-distearoyl-sn-glycero-3-phospho-ethanolamine (DSPE), PEGylated liposome (SL) and PEG-OVA. It appears that HIK-M09 recognizes ethoxy (OCH 2 CH 2 ) repeat units along with a terminal motif of PEG, while HIK-M11 recognizes only ethoxy repeat units of PEG. Such unique properties allow HIK-M09 to bind with dense PEG. In addition, their impact on the in vivo clearance of the PEGylated products was investigated. It was found that the generated ant-PEG IgMs induced a clearance of SL as they were intravenously administered with SL. Interestingly, the HIK-M11, generated by PEG-OVA, induced the clearance of both SL and PEG-OVA, while the HIK-M09, generated by SL, induced the clearance of SL only. We here revealed that the presence of serum anti-PEG IgM and the subsequent binding of anti-PEG IgM to the PEGylated products are not necessarily related to the enhanced clearance of the products. It appears that subsequent complement activation following anti-PEG IgM binding is the most important step in dictating the in vivo fate of PEGylated products. This study may have implications for the design, development and clinical application of PEGylated products and therapeutics. - Highlights: • Two monoclonal anti-PEG Ig

Generation, characterization and in vivo biological activity of two distinct monoclonal anti-PEG IgMs

Energy Technology Data Exchange (ETDEWEB)

Hashimoto, Yosuke; Shimizu, Taro; Mima, Yu [Department of Pharmacokinetics and Biopharmaceutics, Subdivision of Biopharmaceutical Sciences, Institute of Health Biosciences, The University of Tokushima, 1-78-1, Sho-machi, Tokushima 770-8505 (Japan); Abu Lila, Amr S. [Department of Pharmacokinetics and Biopharmaceutics, Subdivision of Biopharmaceutical Sciences, Institute of Health Biosciences, The University of Tokushima, 1-78-1, Sho-machi, Tokushima 770-8505 (Japan); Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Zagazig University, Sharqia Governorate, Zagazig 44519 (Egypt); Ishida, Tatsuhiro, E-mail: ishida@tokushima-u.ac.jp [Department of Pharmacokinetics and Biopharmaceutics, Subdivision of Biopharmaceutical Sciences, Institute of Health Biosciences, The University of Tokushima, 1-78-1, Sho-machi, Tokushima 770-8505 (Japan); Kiwada, Hiroshi [Department of Pharmacokinetics and Biopharmaceutics, Subdivision of Biopharmaceutical Sciences, Institute of Health Biosciences, The University of Tokushima, 1-78-1, Sho-machi, Tokushima 770-8505 (Japan)

2014-05-15

PEGylation, the attachment of polyethylene glycol (PEG) to nanocarriers and proteins, is a widely accepted approach to improving the in vivo efficacy of the non-PEGylated products. However, both PEGylated liposomes and PEGylated proteins reportedly trigger the production of specific antibodies, mainly IgM, against the PEG moiety, which possibly leads to a reduction in safety and therapeutic efficacy of the PEGylated products. In the present study, two monoclonal anti-PEG IgMs — HIK-M09 via immunization with an intravenous injection of PEGylated liposomes (SLs) and HIK-M11 via immunization with a subcutaneous administration of PEGylated ovalbumin (PEG-OVA) were successfully generated. The generated IgMs showed efficient reactivity to mPEG{sub 2000} conjugated to 1,2-distearoyl-sn-glycero-3-phospho-ethanolamine (DSPE), PEGylated liposome (SL) and PEG-OVA. It appears that HIK-M09 recognizes ethoxy (OCH{sub 2}CH{sub 2}) repeat units along with a terminal motif of PEG, while HIK-M11 recognizes only ethoxy repeat units of PEG. Such unique properties allow HIK-M09 to bind with dense PEG. In addition, their impact on the in vivo clearance of the PEGylated products was investigated. It was found that the generated ant-PEG IgMs induced a clearance of SL as they were intravenously administered with SL. Interestingly, the HIK-M11, generated by PEG-OVA, induced the clearance of both SL and PEG-OVA, while the HIK-M09, generated by SL, induced the clearance of SL only. We here revealed that the presence of serum anti-PEG IgM and the subsequent binding of anti-PEG IgM to the PEGylated products are not necessarily related to the enhanced clearance of the products. It appears that subsequent complement activation following anti-PEG IgM binding is the most important step in dictating the in vivo fate of PEGylated products. This study may have implications for the design, development and clinical application of PEGylated products and therapeutics. - Highlights: • Two monoclonal

Phagocytosis of gram-negative bacteria by a unique CD14-dependent mechanism.

Science.gov (United States)

Schiff, D E; Kline, L; Soldau, K; Lee, J D; Pugin, J; Tobias, P S; Ulevitch, R J

1997-12-01

THP-1-derived cell lines were stably transfected with constructs encoding glycophosphatidylinositol (GPI)-anchored or transmembrane forms of human CD14. CD14 expression was associated with enhanced phagocytosis of serum (heat-inactivated)-opsonized Escherichia coli (opEc). Both the GPI-anchored and transmembrane forms of CD14 supported phagocytosis of opEc equally well. Lipopolysaccharide-binding protein (LBP) played a role in CD14-dependent phagocytosis as evidenced by inhibition of CD14-dependent phagocytosis of opEc with anti-LBP monoclonal antibody (mAb) and by enhanced phagocytosis of E. coli opsonized with purified LBP. CD14-dependent phagocytosis was inhibited by a phosphatidylinositol (PI) 3-kinase inhibitor (wortmannin) and a protein tyrosine kinase inhibitor (tyrphostin 23) but not a protein kinase C inhibitor (bisindolyl-maleimide) or a divalent cation chelator (ethylenediaminetetraacetate). Anti-LBP mAb 18G4 and anti-CD14 mAb 18E12 were used to differentiate between the pathways involved in CD14-dependent phagocytosis and CD14-dependent cell activation. F(ab')2 fragments of 18G4, a mAb to LBP that does not block cell activation, inhibited ingestion of opEc by THP1-wtCD14 cells. 18E12 (an anti-CD14 mAb that does not block LPS binding to CD14 but does inhibit CD14-dependent cell activation) did not inhibit phagocytosis of LBP-opEc by THP1-wtCD14 cells. Furthermore, CD14-dependent phagocytosis was not inhibited by anti-CD18 (CR3 and CR4 beta-chain) or anti-Fcgamma receptor mAb.

Sequence-specific interaction between the disintegrin domain of mouse ADAM 3 and murine eggs: role of beta1 integrin-associated proteins CD9, CD81, and CD98.

Science.gov (United States)

Takahashi, Y; Bigler, D; Ito, Y; White, J M

2001-04-01

ADAM 3 is a sperm surface glycoprotein that has been implicated in sperm-egg adhesion. Because little is known about the adhesive activity of ADAMs, we investigated the interaction of ADAM 3 disintegrin domains, made in bacteria and in insect cells, with murine eggs. Both recombinant proteins inhibited sperm-egg binding and fusion with potencies similar to that which we recently reported for the ADAM 2 disintegrin domain. Alanine scanning mutagenesis revealed a critical importance for the glutamine at position 7 of the disintegrin loop. Fluorescent beads coated with the ADAM 3 disintegrin domain bound to the egg surface. Bead binding was inhibited by an authentic, but not by a scrambled, peptide analog of the disintegrin loop. Bead binding was also inhibited by the function-blocking anti-alpha6 monoclonal antibody (mAb) GoH3, but not by a nonfunction blocking anti-alpha6 mAb, or by mAbs against either the alphav or beta3 integrin subunits. We also present evidence that in addition to the tetraspanin CD9, two other beta1-integrin-associated proteins, the tetraspanin CD81 as well as the single pass transmembrane protein CD98 are expressed on murine eggs. Antibodies to CD9 and CD98 inhibited in vitro fertilization and binding of the ADAM 3 disintegrin domain. Our findings are discussed in terms of the involvement of multiple sperm ADAMs and multiple egg beta1 integrin-associated proteins in sperm-egg binding and fusion. We propose that an egg surface "tetraspan web" facilitates fertilization and that it may do so by fostering ADAM-integrin interactions.

Sequence-Specific Interaction between the Disintegrin Domain of Mouse ADAM 3 and Murine Eggs: Role of β1 Integrin-associated Proteins CD9, CD81, and CD98

Science.gov (United States)

Takahashi, Yuji; Bigler, Dora; Ito, Yasuhiko; White, Judith M.

2001-01-01

ADAM 3 is a sperm surface glycoprotein that has been implicated in sperm-egg adhesion. Because little is known about the adhesive activity of ADAMs, we investigated the interaction of ADAM 3 disintegrin domains, made in bacteria and in insect cells, with murine eggs. Both recombinant proteins inhibited sperm-egg binding and fusion with potencies similar to that which we recently reported for the ADAM 2 disintegrin domain. Alanine scanning mutagenesis revealed a critical importance for the glutamine at position 7 of the disintegrin loop. Fluorescent beads coated with the ADAM 3 disintegrin domain bound to the egg surface. Bead binding was inhibited by an authentic, but not by a scrambled, peptide analog of the disintegrin loop. Bead binding was also inhibited by the function-blocking anti-α6 monoclonal antibody (mAb) GoH3, but not by a nonfunction blocking anti-α6 mAb, or by mAbs against either the αv or β3 integrin subunits. We also present evidence that in addition to the tetraspanin CD9, two other β1-integrin-associated proteins, the tetraspanin CD81 as well as the single pass transmembrane protein CD98 are expressed on murine eggs. Antibodies to CD9 and CD98 inhibited in vitro fertilization and binding of the ADAM 3 disintegrin domain. Our findings are discussed in terms of the involvement of multiple sperm ADAMs and multiple egg β1 integrin-associated proteins in sperm-egg binding and fusion. We propose that an egg surface “tetraspan web” facilitates fertilization and that it may do so by fostering ADAM–integrin interactions. PMID:11294888

Effects of estrogen on CD4+CD25+ regulatory T cell in peripheral blood during pregnancy

Institute of Scientific and Technical Information of China (English)

Yuan-Huan Xiong; Zhen Yuan; Li He

2013-01-01

Objective:To investigate the effects of estrogen (E2) level on regulatory T cells (Treg) in peripheral blood during pregnancy. Methods:A total of 30 healthy non-pregnant women were selected as control group, 90 pregnant women of early, middle and late pregnancy and 30 postpartum women at 1 month after parturition were selected as experimental groups including early pregnancy group, middle pregnancy group and late pregnancy group;the proportions of CD4+CD25+Treg and CD4+CD25+CD127-Treg among CD4+T cells were detected by flow cytometry;the serum estrogen content in peripheral blood was detected by electrochemical immune luminescence method. Results: E2 level was coincident with the change of Tregs number during pregnancy. The estrogen content in peripheral blood increased gradually from early pregnancy to late pregnancy, then decreased significantly after parturition, and the level at 1 month after parturition down to the level in non-pregnancy group (P>0.05);the level of E2 in pregnancy groups were significantly higher than those in non-pregnancy group (P0.05);the proportions in middle and late pregnancy groups were significantly higher than those in early pregnancy group (P0.05). There was correlation between Tregs number with estrogen level during pregnancy. The proportion of CD4+CD25+ Treg and CD4+CD25+CD127- Treg were positively correlated with estrogen level. Conclusions:High proportion of CD4+CD25+Treg and CD4+CD25+CD127-Treg is closely related to the high level of E2 during pregnancy. It suggested that high level of estrogen may induce an increase of CD4+CD25+Treg in peripheral blood, and then influence the immune function of pregnant women. The results of this experiment might play an important role of estrogen in immune-modulation during pregnancy.

Detecting fish parvalbumin with commercial mouse monoclonal anti-frog parvalbumin IgG.

Science.gov (United States)

Chen, Lingyun; Hefle, Sue L; Taylor, Steve L; Swoboda, Ines; Goodman, Richard E

2006-07-26

Parvalbumin is a calcium-binding muscle protein that is highly conserved across fish species and amphibians. It is the major cross-reactive allergen associated with both fish and frog allergy. We used two-dimensional electrophoretic and immunoblotting techniques to investigate the utility of a commercial monoclonal anti-frog parvalbumin IgG for detecting parvalbumin present in some commonly consumed fish species. The 2D electrophoresis and immunoblots revealed species-specific differences in proteins that appear to represent various numbers of isoforms of parvalbumin in carp (5), catfish (3), cod (1) and tilapia (2). No parvalbumin was detected in yellowfin tuna. Based on minor differences in relative intensities of protein staining and immunodetection, parvalbumin isoforms may have slight differences in the epitope region recognized by the anti-frog parvalbumin antibody. These results suggest that the frog anti-parvalbumin antibody can be used as a valuable tool to detect parvalbumins from the fish tested in this study, except yellowfin tuna.

CD38+ M-MDSC expansion characterizes a subset of advanced colorectal cancer patients.

Science.gov (United States)

Karakasheva, Tatiana A; Dominguez, George A; Hashimoto, Ayumi; Lin, Eric W; Chiu, Christopher; Sasser, Kate; Lee, Jae W; Beatty, Gregory L; Gabrilovich, Dmitry I; Rustgi, Anil K

2018-03-22

Myeloid-derived suppressor cells (MDSCs) are a population of immature immune cells with several protumorigenic functions. CD38 is a transmembrane receptor-ectoenzyme expressed by MDSCs in murine models of esophageal cancer. We hypothesized that CD38 could be expressed on MDSCs in human colorectal cancer (CRC), which might allow for a new perspective on therapeutic targeting of human MDSCs with anti-CD38 monoclonal antibodies in this cancer. Blood samples were collected from 41 CRC patients and 8 healthy donors, followed by peripheral blood mononuclear cell (PBMC) separation. Polymorphonuclear (PMN-) and monocytic (M-) MDSCs and CD38 expression levels were quantified by flow cytometry. The immunosuppressive capacity of M-MDSCs from 10 CRC patients was validated in a mixed lymphocyte reaction (MLR) assay. A significant expansion of CD38+ M-MDSCs and a trend of expansion of CD38+ PMN-MDSCs (accompanied by a trend of increased CD38 expression on both M- and PMN-MDSCs) were observed in PBMCs of CRC patients when compared with healthy donors. The CD38+ M-MDSCs from CRC patients were found to be immunosuppressive when compared with mature monocytes. CD38+ M- and PMN-MDSC frequencies were significantly higher in CRC patients who previously received treatment when compared with treatment-naive patients. This study provides a rationale for an attempt to target M-MDSCs with an anti-CD38 monoclonal antibody in metastatic CRC patients. NCI P01-CA14305603, the American Cancer Society, Scott and Suzi Lustgarten Family Colon Cancer Research Fund, Hansen Foundation, and Janssen Research and Development.

Monoclonal antibodies targeting CD38 in hematological malignancies and beyond

DEFF Research Database (Denmark)

van de Donk, Niels W C J; Janmaat, Maarten L.; Mutis, Tuna

2016-01-01

CD38 is a multifunctional cell surface protein that has receptor as well as enzyme functions. The protein is generally expressed at low levels on various hematological and solid tissues, while plasma cells express particularly high levels of CD38. The protein is also expressed in a subset of hema...... strong anti-tumor activity in preclinical models. The antibody engages diverse mechanisms of action, including complement-dependent cytotoxicity, antibody-dependent cellular cytotoxicity, antibody-dependent cellular phagocytosis, programmed cell death, modulation of enzymatic activity...... combination therapies with existing as well as emerging therapies, which are currently evaluated in the clinic. Finally, CD38 antibodies may have a role in the treatment of diseases beyond hematological malignancies, including solid tumors and antibody-mediated autoimmune diseases. © 2016 John Wiley & Sons A....../S. Published by John Wiley & Sons Ltd....

Detection and Significance of CD4+CD25+CD127dim Regulatory T Cells in Individuals with Severe Aplastic Anemia

Directory of Open Access Journals (Sweden)

Weiwei Qi

2015-09-01

Full Text Available Objective: To investigate the relationship between CD4+CD25+CD127dim regulatory T cells (Tregs and immune imbalance in acquired severe aplastic anemia (SAA. Materials and Methods: The quantity of CD4+CD25+CD127dim Tregs in 44 SAA patients and 23 normal controls was measured by flow cytometry. Correlations between Tregs and T cell subsets, dendritic cell (DC subsets, granulocyte counts, and percentage of reticulocytes (RET% were analyzed. Results: The percentage of CD4+CD25+CD127dim Tregs in peripheral blood lymphocytes (PBLs of untreated patients was lower than in recovery patients and normal controls (0.83±0.44% vs. 2.91±1.24% and 2.18±0.55%, respectively, p<0.05. The percentage of CD4+CD25+CD127dim Tregs in CD4+ T lymphocytes of recovery patients was higher than that of untreated patients and normal controls (9.39±3.51% vs. 7.61±5.3% and 6.83±1.4%, respectively, p<0.05. The percentage of CD4+ T lymphocytes in PBLs of untreated patients was lower than in recovery patients and normal controls (13.55±7.37% vs. 31.82±8.43% and 32.12±5.88%, respectively, p<0.05. T cell subset (CD4+/CD8+ ratio was 0.41±0.24 in untreated patients, which was lower than in recovery patients (1.2±0.4 and normal controls (1.11±0.23 (p<0.05. DC subset (myeloid DC/plasmacytoid DC ratio, DC1/DC2 ratio was 3.08±0.72 in untreated patients, which was higher than in recovery patients (1.61±0.49 and normal controls (1.39±0.36 (p<0.05. The percentage of CD4+CD25+CD127dim Tregs in PBLs was positively associated with T cell subset (r=0.955, p<0.01 and negatively associated with DC subset (r=-0.765, p<0.01. There were significant positive correlations between CD4+CD25+CD127dim Tregs/PBL and granulocyte counts and RET% (r=0.739 and r=0.749, respectively, p<0.01. Conclusion: The decrease of CD4+CD25+CD127dim Tregs in SAA patients may cause excessive functioning of T lymphocytes and thus lead to hematopoiesis failure in SAA.

Structure of Simian Immunodeficiency Virus Envelope Spikes Bound with CD4 and Monoclonal Antibody 36D5.

Science.gov (United States)

Hu, Guiqing; Liu, Jun; Roux, Kenneth H; Taylor, Kenneth A

2017-08-15

The human immunodeficiency virus type 1 (HIV-1)/simian immunodeficiency virus (SIV) envelope spike (Env) mediates viral entry into host cells. The V3 loop of the gp120 component of the Env trimer contributes to the coreceptor binding site and is a target for neutralizing antibodies. We used cryo-electron tomography to visualize the binding of CD4 and the V3 loop monoclonal antibody (MAb) 36D5 to gp120 of the SIV Env trimer. Our results show that 36D5 binds gp120 at the base of the V3 loop and suggest that the antibody exerts its neutralization effect by blocking the coreceptor binding site. The antibody does this without altering the dynamics of the spike motion between closed and open states when CD4 is bound. The interaction between 36D5 and SIV gp120 is similar to the interaction between some broadly neutralizing anti-V3 loop antibodies and HIV-1 gp120. Two conformations of gp120 bound with CD4 are revealed, suggesting an intrinsic dynamic nature of the liganded Env trimer. CD4 binding substantially increases the binding of 36D5 to gp120 in the intact Env trimer, consistent with CD4-induced changes in the conformation of gp120 and the antibody binding site. Binding by MAb 36D5 does not substantially alter the proportions of the two CD4-bound conformations. The position of MAb 36D5 at the V3 base changes little between conformations, indicating that the V3 base serves as a pivot point during the transition between these two states. IMPORTANCE Glycoprotein spikes on the surfaces of SIV and HIV are the sole targets available to the immune system for antibody neutralization. Spikes evade the immune system by a combination of a thick layer of polysaccharide on the surface (the glycan shield) and movement between spike domains that masks the epitope conformation. Using SIV virions whose spikes were "decorated" with the primary cellular receptor (CD4) and an antibody (36D5) at part of the coreceptor binding site, we visualized multiple conformations trapped by the

CD33 monoclonal antibody conjugated Au cluster nano-bioprobe for targeted flow-cytometric detection of acute myeloid leukaemia

Science.gov (United States)

Retnakumari, Archana; Jayasimhan, Jasusri; Chandran, Parwathy; Menon, Deepthy; Nair, Shantikumar; Mony, Ullas; Koyakutty, Manzoor

2011-07-01

Protein stabilized gold nanoclusters (Au-NCs) are biocompatible, near-infrared (NIR) emitting nanosystems having a wide range of biomedical applications. Here, we report the development of a Au-NC based targeted fluorescent nano-bioprobe for the flow-cytometric detection of acute myeloid leukaemia (AML) cells. Au-NCs with ~ 25-28 atoms showing bright red-NIR fluorescence (600-750 nm) and average size of ~ 0.8 nm were prepared by bovine serum albumin assisted reduction-cum-stabilization in aqueous phase. The protein protected clusters were conjugated with monoclonal antibody against CD33 myeloid antigen, which is overexpressed in ~ 99.2% of the primitive population of AML cells, as confirmed by immunophenotyping using flow cytometry. Au-NC-CD33 conjugates having average size of ~ 12 nm retained bright fluorescence over an extended duration of ~ a year, as the albumin protein protects Au-NCs against degradation. Nanotoxicity studies revealed excellent biocompatibility of Au-NC conjugates, as they showed no adverse effect on the cell viability and inflammatory response. Target specificity of the conjugates for detecting CD33 expressing AML cells (KG1a) in flow cytometry showed specific staining of ~ 95.4% of leukaemia cells within 1-2 h compared to a non-specific uptake of ~ 8.2% in human peripheral blood cells (PBMCs) which are CD33low. The confocal imaging also demonstrated the targeted uptake of CD33 conjugated Au-NCs by leukaemia cells, thus confirming the flow cytometry results. This study demonstrates that novel nano-bioprobes can be developed using protein protected fluorescent nanoclusters of Au for the molecular receptor targeted flow cytometry based detection and imaging of cancer cells.

CD33 monoclonal antibody conjugated Au cluster nano-bioprobe for targeted flow-cytometric detection of acute myeloid leukaemia

International Nuclear Information System (INIS)

Retnakumari, Archana; Jayasimhan, Jasusri; Chandran, Parwathy; Menon, Deepthy; Nair, Shantikumar; Mony, Ullas; Koyakutty, Manzoor

2011-01-01

Protein stabilized gold nanoclusters (Au-NCs) are biocompatible, near-infrared (NIR) emitting nanosystems having a wide range of biomedical applications. Here, we report the development of a Au-NC based targeted fluorescent nano-bioprobe for the flow-cytometric detection of acute myeloid leukaemia (AML) cells. Au-NCs with ∼ 25-28 atoms showing bright red-NIR fluorescence (600-750 nm) and average size of ∼ 0.8 nm were prepared by bovine serum albumin assisted reduction-cum-stabilization in aqueous phase. The protein protected clusters were conjugated with monoclonal antibody against CD33 myeloid antigen, which is overexpressed in ∼ 99.2% of the primitive population of AML cells, as confirmed by immunophenotyping using flow cytometry. Au-NC-CD33 conjugates having average size of ∼ 12 nm retained bright fluorescence over an extended duration of ∼ a year, as the albumin protein protects Au-NCs against degradation. Nanotoxicity studies revealed excellent biocompatibility of Au-NC conjugates, as they showed no adverse effect on the cell viability and inflammatory response. Target specificity of the conjugates for detecting CD33 expressing AML cells (KG1a) in flow cytometry showed specific staining of ∼ 95.4% of leukaemia cells within 1-2 h compared to a non-specific uptake of ∼ 8.2% in human peripheral blood cells (PBMCs) which are CD33 low . The confocal imaging also demonstrated the targeted uptake of CD33 conjugated Au-NCs by leukaemia cells, thus confirming the flow cytometry results. This study demonstrates that novel nano-bioprobes can be developed using protein protected fluorescent nanoclusters of Au for the molecular receptor targeted flow cytometry based detection and imaging of cancer cells.

CD33 monoclonal antibody conjugated Au cluster nano-bioprobe for targeted flow-cytometric detection of acute myeloid leukaemia

Energy Technology Data Exchange (ETDEWEB)

Retnakumari, Archana; Jayasimhan, Jasusri; Chandran, Parwathy; Menon, Deepthy; Nair, Shantikumar; Mony, Ullas; Koyakutty, Manzoor, E-mail: manzoork@aims.amrita.edu, E-mail: ullasmony@aims.amrita.edu [Amrita Centre for Nanoscience and Molecular Medicine, Amrita Institute of Medical Science, Cochin 682 041 (India)

2011-07-15

Protein stabilized gold nanoclusters (Au-NCs) are biocompatible, near-infrared (NIR) emitting nanosystems having a wide range of biomedical applications. Here, we report the development of a Au-NC based targeted fluorescent nano-bioprobe for the flow-cytometric detection of acute myeloid leukaemia (AML) cells. Au-NCs with {approx} 25-28 atoms showing bright red-NIR fluorescence (600-750 nm) and average size of {approx} 0.8 nm were prepared by bovine serum albumin assisted reduction-cum-stabilization in aqueous phase. The protein protected clusters were conjugated with monoclonal antibody against CD33 myeloid antigen, which is overexpressed in {approx} 99.2% of the primitive population of AML cells, as confirmed by immunophenotyping using flow cytometry. Au-NC-CD33 conjugates having average size of {approx} 12 nm retained bright fluorescence over an extended duration of {approx} a year, as the albumin protein protects Au-NCs against degradation. Nanotoxicity studies revealed excellent biocompatibility of Au-NC conjugates, as they showed no adverse effect on the cell viability and inflammatory response. Target specificity of the conjugates for detecting CD33 expressing AML cells (KG1a) in flow cytometry showed specific staining of {approx} 95.4% of leukaemia cells within 1-2 h compared to a non-specific uptake of {approx} 8.2% in human peripheral blood cells (PBMCs) which are CD33{sup low}. The confocal imaging also demonstrated the targeted uptake of CD33 conjugated Au-NCs by leukaemia cells, thus confirming the flow cytometry results. This study demonstrates that novel nano-bioprobes can be developed using protein protected fluorescent nanoclusters of Au for the molecular receptor targeted flow cytometry based detection and imaging of cancer cells.

Nanoscale Relationship Between CD4 and CD25 of T Cells Visualized with NSOM/QD-Based Dual-Color Imaging System

Science.gov (United States)

Fan, Jinping; Lu, Xiaoxu; Liu, Shengde; Zhong, Liyun

2015-10-01

In this study, by using of near-field scanning optical microscopy (NSOM)/immune-labeling quantum dot (QD)-based dual-color imaging system, we achieved the direct visualization of nanoscale profiles for distribution and organization of CD4 and CD25 molecules in T cells. A novel and interesting finding was that though CD25 clustering as nanodomains were observed on the surface of CD4+CD25high regulatory T cells, these CD25 nanodomains were not co-localized with CD4 nanodomains. This result presented that the formation of these CD25 nanodomains on the surface of CD4+CD25high T cells were not associated with the response of T cell receptor (TCR)/CD3-dependent signal transduction. In contrast, on the surface of CD4+CD25low T cells, CD25 molecules distributed randomly without forming nanodomains while CD4 clustering as nanodomains can be observed; on the surface of CD8+CD25+ T cells, CD25 clustering as nanodomains and co-localization with CD8 nanodomains were observed. Collectively, above these results exhibited that TCR/CD3-based microdomains were indeed required for TCR/CD3-mediated T cells activation and enhanced the immune activity of CD4+CD25low T cells or CD8+CD25+ T cells. In particular, it was found that the formation of CD25 nanodomains and their segregation from TCR/CD3 microdomains were the intrinsic capability of CD4+CD25high T cells, suggesting this specific imaging feature of CD25 should be greatly associated with the regulatory activity of CD4+CD25high T cells. Importantly, this novel NSOM/QD-based dual-color imaging system will provide a useful tool for the research of distribution-function relationship of cell-surface molecules.

Clinical application of antibody monoclonal humanized anti-EGFrnimotuzumab labeled

International Nuclear Information System (INIS)

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

2016-01-01

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

CD40-CD40 Ligand Pathway is a Major Component of Acute Neuroinflammation and Contributes to Long-term Cognitive Dysfunction after Sepsis.

Science.gov (United States)

Michels, Monique; Danieslki, Lucinéia Gainski; Vieira, Andriele; Florentino, Drielly; Dall'Igna, Dhébora; Galant, Letícia; Sonai, Beatriz; Vuolo, Francieli; Mina, Franciele; Pescador, Bruna; Dominguini, Diogo; Barichello, Tatiana; Quevedo, João; Dal-Pizzol, Felipe; Petronilho, Fabrícia

2015-03-26

Sepsis-associated encephalopathy (SAE) is associated with an increased rate of morbidity and mortality. It is not understood what the exact mechanism is for the brain dysfunction that occurs in septic patients, but brain inflammation and oxidative stress are a possible theory. Such events can occur through the alteration of molecules that perpetuate the inflammatory response. Thus, it is possible to postulate that CD40 may be involved in this process. The aim of this work is to evaluate the role of CD40-CD40L pathway activation in brain dysfunction associated with sepsis in an animal model. Microglia activation induces the upregulation of CD40-CD40L, both in vitro and in vivo. The inhibition of microglia activation decreases levels of CD40-CD40L in the brain and decreases brain inflammation, oxidative damage and blood brain barrier dysfunction. Despite this, anti-CD40 treatment does not improve mortality in this model. However, it is able to improve long-term cognitive impairment in sepsis survivors. In conclusion, there is a major involvement of the CD40-CD40L signaling pathway in long-term brain dysfunction in an animal model of sepsis.

Quantitative variations of CD4 + CD25 + cells in Peking duckwhite ...

African Journals Online (AJOL)

Quantitative variations of CD4 + CD25 + cells in Peking duckwhite leghorn chimeras based on bone marrow mesenchymal stem cells. ... Tropical Journal of Pharmaceutical Research. Journal Home · ABOUT THIS JOURNAL · Advanced ...

Estudio de las subpoblaciones linfocitarias T en pacientes pediátricos con anomalías tronco-conales cardiovasculares Study of the T-lymphocyte subpopulations in pediatric patients with conal-truncal cardiovascular abnormalities

Directory of Open Access Journals (Sweden)

Bertha Beatriz Socarrás Ferrer

2006-12-01

Full Text Available Se estudiaron en 20 pacientes pediátricos con anomalías tronco-conales cardiovasculares las subpoblaciones de linfocitos T mediante el método de la fosfatasa alcalina antifosfatasa alcalina con los anticuerpos monoclonales específicos anti-CD3, anti-CD4 y anti-CD8. Se tomó como grupo control a 25 individuos supuestamente sanos. Se obtuvieron diferencias significativas para las subpoblaciones T CD3 y CD4 positivas (p The T-lymphocyte subpopulations were studied in 20 pediatric patients with conal-truncal cardiovascular abnormalities by the alkaline phosphatase alkaline antiphosphatase method with the anti-CD3, anti-CD4, and anti-CD8 specific monoclonal antibodies. 25 apparently sound individuals were selected as the control group. Significant differences were obtained for the CD3- and CD4-positive T cell subpopulations (p< 0.05. The cellular immunological deficit found in these patients shows the need to include immunomodulators in their treatment to prevent septic complications

Role of polymorphic Fc receptor Fc gammaRIIa in cytokine release and adverse effects of murine IgG1 anti-CD3/T cell receptor antibody (WT31).

Science.gov (United States)

Tax, W J; Tamboer, W P; Jacobs, C W; Frenken, L A; Koene, R A

1997-01-15

Anti-CD3 monoclonal antibody (mAb) OKT3 is immunosuppressive, but causes severe adverse effects during the first administration ("first-dose reaction"). These adverse effects are presumably caused by cytokine release that results from T-cell activation. In vitro, T-cell activation by anti-CD3 mAb requires interaction with monocyte Fc receptors. The Fc receptor for murine IgG1, Fc gammaRIIa, is polymorphic. In some individuals, murine IgG1 anti-CD3 mAb causes T-cell proliferation and cytokine release in vitro (high responders [HR]), whereas in individuals with the low-responder (LR) phenotype it does not. We have now investigated the role of this Fc gammaRIIa polymorphism in the release of cytokines in vivo and the occurrence of adverse effects after the administration of WT31, a murine IgG1 anti-CD3/T cell receptor mAb. WT31 caused an increase of plasma tumor necrosis factor-alpha in all four HR patients and none of the five LR patients. In all HR patients except one, plasma gamma-interferon and interleukin 6 also increased, and a first-dose response was observed, whereas no cytokine release or adverse effects occurred in any of the LR patients. WT31 caused lymphopenia in all HR and none of the LR patients. FACS analysis demonstrated that in HR patients, after the initial disappearance of CD3+ cells from peripheral blood, modulation of CD3 occurred, whereas in LR patients a high degree of coating of the lymphocytes was observed. Surprisingly, WT31 also induced a marked granulocytopenia, as well as a decrease of thrombocytes, in three of the four HR patients (and in none of the LR patients). These data provide direct clinical evidence that Fc receptor interaction determines the release of cytokines and the occurrence of adverse effects after administration of anti-CD3/T cell receptor mAb. Furthermore, these data suggest that tumor necrosis factor-alpha by itself is not sufficient to induce the first-dose reaction.

Does pretransplant soluble CD30 serum concentration affect deceased-donor kidney graft function 3 years after transplantation?

Science.gov (United States)

Kovac, J; Arnol, M; Vidan-Jeras, B; Bren, A F; Kandus, A

2008-06-01

Elevated serum concentrations of soluble CD30 molecule (sCD30) have been related to acute cellular rejection and poor graft outcomes in kidney transplantation. This historical cohort study investigated the association of pretransplant sCD30 serum concentrations with kidney graft function expressed as estimated glomerular filtration rate (GFR) at 3 years after transplantation. Pretransplant sera from 176 adult deceased-donor kidney graft recipients were tested for sCD30 content using a commercially available automated enzyme-linked immunosorbent assay. The immunosuppression consisted of induction therapy with monoclonal anti-CD25 antibodies and a maintenance regimen of cyclosporine (CsA)-based therapy. GFR was estimated (eGFR) by the four-variable Modification of Diet in Renal Disease (MDRD) Study equation. According to the distribution of pretransplant sCD30 levels (median 66.7 U/mL; interquartile range, 46.6 to 98.6 U/mL), a concentration of 66 U/mL or higher was defined as high (n = 89) and below 66 U/mL as low (n = 87). Three years after transplantation, eGFR was not significantly different among recipients in high versus low sCD30 groups (69 +/- 23 mL/min/1.73m2 vs 66 +/- 21 mL/min/1.73m2; P = .327) and there was no correlation between eGFR and pretransplant sCD30 levels (r2 = 0.001; P = .73). Upon multivariate regression analysis, donor age, recipient body mass index at transplantation, and acute rejection episodes were independent variables affecting eGFR at 3 years after transplantation. This study showed that pretransplant sCD30 serum concentrations were not associated with deceased-donor kidney graft function at 3 years after transplantation. The immunosuppression with anti-CD25 antibodies and a triple CsA-based maintenance regimen could possibly be decisive for our findings.

Natural CD8+25+ regulatory T cell-secreted exosomes capable of suppressing cytotoxic T lymphocyte-mediated immunity against B16 melanoma

International Nuclear Information System (INIS)

Xie, Yufeng; Zhang, Xueshu; Zhao, Tuo; Li, Wei; Xiang, Jim

2013-01-01

Highlights: •CD8 + 25 + regulatory T cells secrete tolerogenic exosomes. •CD8 + 25 + regulatory T cell-derived exosomes exhibit immunosuppressive effect. •CD8 + 25 + regulatory T cell-derived exosomes inhibit antitumor immunity. -- Abstract: Natural CD4 + 25 + and CD8 + 25 + regulatory T (Tr) cells have been shown to inhibit autoimmune diseases. Immune cells secrete exosomes (EXOs), which are crucial for immune regulation. However, immunomodulatory effect of natural Tr cell-secreted EXOs is unknown. In this study, we purified natural CD8 + 25 + Tr cells from C57BL/6 mouse naive CD8 + T cells, and in vitro amplified them with CD3/CD28 beads. EXOs (EXO Tr ) were purified from Tr cell’s culture supernatants by differential ultracentrifugation and analyzed by electron microscopy, Western blot and flow cytometry. Our data showed that EXO Tr had a “saucer” or round shape with 50–100 nm in diameter, contained EXO-associated markers LAMP-1 and CD9, and expressed natural Tr cell markers CD25 and GITR. To assess immunomodulatory effect, we i.v. immunized C57BL/6 mice with ovalbumin (OVA)-pulsed DCs (DC OVA ) plus Tr cells or EXO Tr , and then assessed OVA-specific CD8 + T cell responses using PE-H-2K b /OVA tetramer and FITC-anti-CD8 antibody staining by flow cytometry and antitumor immunity in immunized mice with challenge of OVA-expressing BL6–10 OVA melanoma cells. We demonstrated that DC OVA -stimulated CD8 + T cell responses and protective antitumor immunity significantly dropped from 2.52% to 1.08% and 1.81% (p OVA (p Tr , respectively. Our results indicate that natural CD8 + 25 + Tr cell-released EXOs, alike CD8 + 25 + Tr cells, can inhibit CD8 + T cell responses and antitumor immunity. Therefore, EXOs derived from natural CD4 + 25 + and CD8 + 25 + Tr cells may become an alternative for immunotherapy of autoimmune diseases

Short-term effects of early-acting and multilineage hematopoietic growth factors on the repair and proliferation of irradiated pure cord blood (CB) CD34 hematopoietic progenitor cells

International Nuclear Information System (INIS)

Ziegler, Benedikt L.; Sandor, Peter S.; Plappert, Ulla; Thoma, Stefan; Mueller, Robert; Bock, Thomas; Thomas, Christian A.; Nothdurft, Wilhelm; Fliedner, Theodor M.

1998-01-01

Purpose: Hematopoietic growth factor(s) (GF) may exert positive effects in vitro or in vivo on the survival of hematopoietic stem and progenitor cells after accidental or therapeutic total body irradiation. Methods and Materials: We studied the clonogenic survival and DNA repair of irradiated (0.36, 0.73, and 1.46 Gy) CD34 + cord blood (CB) cells after short-term incubation (24 h) with GFs. CD34 + cells were stimulated with basic fibroblast growth factor (bFGF), stem cell factor/c-kit ligand (SCF), interleukin-3 (IL-3), IL-6, leukemia inhibitory factor (LIF), and granulocyte-monocyte colony stimulating factor (GM-CSF) alone or in combination in short-term serum-free liquid suspension cultures (LSC) immediately after irradiation and then assayed for clonogenic progenitors. DNA repair was evaluated by analysis of DNA strand breaks using the comet assay. Survival of CFU-GM, BFU-E, and CFU-Mix was determined and dose-response curves were fitted to the data. Results: The radiobiological parameters (D 0 and n) showed significant GF(s) effects. Combination of IL-3 with IL-6, SCF or GM-CSF resulted in best survival for CFU-GM BFU-E and CFU-Mix, respectively. Combinations of three or more GFs did not increase the survival of clonogenic CD34 + cells compared to optimal two-factor combinations. The D 0 values for CFU-GM, BFU-E, and CFU-Mix ranged between 0.56-1.15, 0.41-2.24, and 0.56-1.29 Gy, respectively. As for controls, the curves remained strictly exponential, i.e., all survival curves were strictly exponential without any shoulder (extrapolation numbers n = 1 for all tested GF(s). DNA repair capacity of CD34 + cells determined by comet assay, was measured before, immediately after irradiation, as well as 30 and 120 min after irradiation at 1 Gy. Notably, after irradiation the 2-h repair of cytokine-stimulated and unstimulated CD34 + cells was similar. Conclusion: Our data indicate that increased survival of irradiated CB CD34 + cells after short-term GF treatment is

Neuropilin-1highCD4+CD25+ Regulatory T Cells Exhibit Primary Negative Immunoregulation in Sepsis

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Yu-Lei Gao

2016-01-01

Full Text Available Regulatory T cells (Tregs appear to be involved in sepsis-induced immune dysfunction; neuropilin-1 (Nrp-1 was identified as a surface marker for CD4+CD25+Tregs. In the current study, we investigated the negative immunoregulation of Nrp-1highCD4+CD25+Tregs and the potential therapeutic value of Nrp-1 in sepsis. Splenic CD4+CD25+Tregs from cecal ligation and puncture (CLP mouse models were further segregated into Nrp-1highTregs and Nrp-1lowTregs; they were cocultured with CD4+CD25−  T cells. The expression of forkhead/winged helix transcription factor-3 (Foxp-3, cytotoxic T-lymphocyte associated antigen-4 (CTLA-4, membrane associated transforming growth factor-β (TGF-βm+, apoptotic rate, and secretive ability [including TGF-β and interleukin-10 (IL-10] for various types of Tregs, as well as the immunosuppressive ability of Tregs on CD4+CD25−  T cells, were determined. Meanwhile, the impact of recombinant Nrp-1 polyclonal antibody on the demethylation of Foxp-3-TSDR (Treg-specific demethylated region was measured in in vitro study. Sepsis per se markedly promoted the expression of Nrp-1 of CD4+CD25+Tregs. Foxp-3/CTLA-4/TGF-βm+ of Nrp-1highTregs were upregulated by septic challenge. Nrp-1highTregs showed strong resilience to apoptosis and secretive ability and the strongest immunosuppressive ability on CD4+CD25−  T cells. In the presence of lipopolysaccharide (LPS, the recombinant Nrp-1 polyclonal antibody reduced the demethylation of Foxp-3-TSDR. Nrp-1highTregs might reveal primary negative immunoregulation in sepsis; Nrp-1 could represent a new potential therapeutic target for the study of immune regulation in sepsis.

Identification of relevant drugable targets in diffuse large B-cell lymphoma using a genome-wide unbiased CD20 guilt-by association approach

NARCIS (Netherlands)

de Jong, Mathilde R. W.; Visser, Lydia; Huls, Gerwin; Diepstra, Arjan; van Vugt, Marcel; Ammatuna, Emanuele; van Rijn, Rozemarijn S.; Vellenga, Edo; van den Berg, Anke; Fehrmann, Rudolf S. N.; van Meerten, Tom

2018-01-01

Forty percent of patients with diffuse large B-cell lymphoma (DLBCL) show resistant disease to standard chemotherapy (CHOP) in combination with the anti-CD20 monoclonal antibody rituximab (R). Although many new anti-cancer drugs were developed in the last years, it is unclear which of these drugs

Neurotrophins play differential roles in short and long-term recognition memory.

Science.gov (United States)

Callaghan, Charlotte K; Kelly, Aine M

2013-09-01

The neurotrophin family of proteins are believed to mediate various forms of synaptic plasticity in the adult brain. Here we have assessed the roles of these proteins in object recognition memory in the rat, using icv infusions of function-blocking antibodies or the tyrosine kinase antagonist, tyrphostin AG879, to block Trk receptors. We report that tyrphostin AG879 impairs both short-term and long-term recognition memory, indicating a requirement for Trk receptor activation in both processes. The effect of inhibition of each of the neurotrophins with activity-blocking neutralising antibodies was also tested. Treatment with anti-BDNF, anti-NGF or anti-NT4 had no effect on short-term memory, but blocked long-term recognition memory. Treatment with anti-NT3 had no effect on either process. We also assessed changes in expression of neurotrophins and their respective receptors in the hippocampus, dentate gyrus and perirhinal cortex over a 24 h period following training in the object recognition task. We observed time-dependent changes in expression of the Trk receptors and their ligands in the dentate gyrus and perirhinal cortex. The data are consistent with a pivotal role for neurotrophic factors in the expression of recognition memory. Copyright © 2013 Elsevier Inc. All rights reserved.

Can Metabolic Factors be used Prognostically for Short.Term ...

African Journals Online (AJOL)

to be promising short.term mortality markers in HIV patients apart from established factors like low CD4 counts, co.morbid conditions, and opportunistic infections like M. tuberculosis infection. This study warrants further studies with a larger sample size to establish HDL and triglyceride as markers of disease progression and ...

A novel anti-EMMPRIN function-blocking antibody reduces T cell proliferation and neurotoxicity: relevance to multiple sclerosis.

Science.gov (United States)

Agrawal, Smriti M; Silva, Claudia; Wang, Janet; Tong, Jade Pui-Wai; Yong, V Wee

2012-04-05

Extracellular matrix metalloproteinase inducer (EMMPRIN; CD147, basigin) is an inducer of the expression of several matrix metalloproteinases (MMPs). We reported previously that blocking EMMPRIN activity reduced neuroinflammation and severity of disease in an animal model of multiple sclerosis (MS), experimental autoimmune encephalomyelitis (EAE). To improve upon EMMPRIN blockade, and to help unravel the biological functions of EMMPRIN in inflammatory disorders, we have developed several anti-EMMPRIN monoclonal antibodies. Of these monoclonal antibodies, a particular one, clone 10, was efficient in binding mouse and human cells using several methods of detection. The specificity of clone 10 was demonstrated by its lack of staining of EMMPRIN-null embryos compared to heterozygous and wild-type mouse samples. Functionally, human T cells activated with anti-CD3 and anti-CD28 elevated their expression of EMMPRIN and the treatment of these T cells with clone 10 resulted in decreased proliferation and matrix metalloproteinase- 9 (MMP-9) production. Activated human T cells were toxic to human neurons in culture and clone 10 pretreatment reduced T cell cytotoxicity correspondent with decrease of granzyme B levels within T cells. In vivo, EAE mice treated with clone 10 had a markedly reduced disease score compared to mice treated with IgM isotype control. We have produced a novel anti-EMMPRIN monoclonal antibody that blocks several aspects of T cell activity, thus highlighting the multiple roles of EMMPRIN in T cell biology. Moreover, clone 10 reduces EAE scores in mice compared to controls, and has activity on human cells, potentially allowing for the testing of anti-EMMPRIN treatment not only in EAE, but conceivably also in MS.

A novel anti-EMMPRIN function-blocking antibody reduces T cell proliferation and neurotoxicity: relevance to multiple sclerosis

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Agrawal Smriti M

2012-04-01

Full Text Available Abstract Background Extracellular matrix metalloproteinase inducer (EMMPRIN; CD147, basigin is an inducer of the expression of several matrix metalloproteinases (MMPs. We reported previously that blocking EMMPRIN activity reduced neuroinflammation and severity of disease in an animal model of multiple sclerosis (MS, experimental autoimmune encephalomyelitis (EAE. Methods To improve upon EMMPRIN blockade, and to help unravel the biological functions of EMMPRIN in inflammatory disorders, we have developed several anti-EMMPRIN monoclonal antibodies. Results Of these monoclonal antibodies, a particular one, clone 10, was efficient in binding mouse and human cells using several methods of detection. The specificity of clone 10 was demonstrated by its lack of staining of EMMPRIN-null embryos compared to heterozygous and wild-type mouse samples. Functionally, human T cells activated with anti-CD3 and anti-CD28 elevated their expression of EMMPRIN and the treatment of these T cells with clone 10 resulted in decreased proliferation and matrix metalloproteinase- 9 (MMP-9 production. Activated human T cells were toxic to human neurons in culture and clone 10 pretreatment reduced T cell cytotoxicity correspondent with decrease of granzyme B levels within T cells. In vivo, EAE mice treated with clone 10 had a markedly reduced disease score compared to mice treated with IgM isotype control. Conclusions We have produced a novel anti-EMMPRIN monoclonal antibody that blocks several aspects of T cell activity, thus highlighting the multiple roles of EMMPRIN in T cell biology. Moreover, clone 10 reduces EAE scores in mice compared to controls, and has activity on human cells, potentially allowing for the testing of anti-EMMPRIN treatment not only in EAE, but conceivably also in MS.

Telomere length analysis in monoclonal B-cell lymphocytosis and chronic lymphocytic leukemia Binet A

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F.M. Furtado

Full Text Available Monoclonal B-cell lymphocytosis (MBL is an asymptomatic clinical entity characterized by the proliferation of monoclonal B cells not meeting the diagnosis criteria for chronic lymphocytic leukemia (CLL. MBL may precede the development of CLL, but the molecular mechanisms responsible for disease progression and evolution are not completely known. Telomeres are usually short in CLL and their attrition may contribute to disease evolution. Here, we determined the telomere lengths of CD5+CD19+ cells in MBL, CLL, and healthy volunteers. Twenty-one CLL patients, 11 subjects with high-count MBL, and 6 with low-count MBL were enrolled. Two hundred and sixty-one healthy volunteers aged 0 to 88 years were studied as controls. After diagnosis confirmation, a flow cytometry CD19+CD5+-based cell sorting was performed for the study groups. Telomere length was determined by qPCR. Telomere length was similar in the 3 study groups but shorter in these groups compared to normal age-matched subjects that had been enrolled in a previous study from our group. These findings suggest that telomere shortening is an early event in CLL leukemogenesis.

Monoclonal anti-human factor VII antibodies. Detection in plasma of a second protein antigenically and genetically related to factor VII.

OpenAIRE

Broze, G J; Hickman, S; Miletich, J P

1985-01-01

Several murine monoclonal anti-human Factor VII antibodies were produced using hybridoma technology. Two noncompetitive monoclonal antibodies were used to examine by Western blotting the Factor VII cross-reactive material (CRM) in normal human plasma and three commercially available congenitally Factor VII-deficient plasmas, and to construct a facile "sandwich" immunoassay for plasma Factor VII. A second, previously undescribed, form of Factor VII CRM was detected in human plasma, which on We...

SHORT-TERM MEMORY IS INDEPENDENT OF BRAIN PROTEIN SYNTHESIS

Energy Technology Data Exchange (ETDEWEB)

Davis, Hasker P.; Rosenzweig, Mark R.; Jones, Oliver W.

1980-09-01

Male Swiss albino CD-1 mice given a single injection of a cerebral protein synthesis inhibitor, anisomycin (ANI) (1 mg/animal), 20 min prior to single trial passive avoidance training demonstrated impaired retention at tests given 3 hr, 6 hr, 1 day, and 7 days after training. Retention was not significantly different from saline controls when tests were given 0.5 or 1.5 hr after training. Prolonging inhibition of brain protein synthesis by giving either 1 or 2 additional injections of ANI 2 or 2 and 4 hr after training did not prolong short-term retention performance. The temporal development of impaired retention in ANI treated mice could not be accounted for by drug dosage, duration of protein synthesis inhibition, or nonspecific sickness at test. In contrast to the suggestion that protein synthesis inhibition prolongs short-term memory (Quinton, 1978), the results of this experiment indicate that short-term memory is not prolonged by antibiotic drugs that inhibit cerebral protein synthesis. All evidence seems consistent with the hypothesis that short-term memory is protein synthesis independent and that the establishment of long-term memory depends upon protein synthesis during or shortly after training. Evidence for a role of protein synthesis in memory maintenance is discussed.

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

International Nuclear Information System (INIS)

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

1985-01-01

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

[Standardization of the quantitative flow cytometric test with anti-D antibodies for fetomaternal hemorrhage in RhD negative women].

Science.gov (United States)

Spychalska, Justyna; Uhrynowska, Małgorzata; Pyl, Hanna; Klimczak-Jajor, Edyta; Kopeć, Izabella; Peciakowska, Małgorzata; Gutowska, Renata; Gawlak, Maciej; Słomska, Sylwia; Dąbkowska, Syiwia; Szczecina, Roman; Dębska, Marzena; Brojer, Ewa

2015-07-01

In order to determine the appropriate dose of anti-D immunoglobulin to be administered as a preventive measure against hemolytic disease of the fetus/newborn in the subsequent pregnancy it is necessary to assess the number of fetal red blood cells that infiltrate/penetrate into the maternal circulation as a result of fetomaternal hemorrhage (FMH). One of the quantitative methods of FMH analysis is based on flow cytometry (FACS) which makes use of monoclonal antibodies to RhD antigen (anti-D test). The aim of the study was to further develop the method, evaluate its sensitivity and reproducibility and to compare it with the test based on the detection of fetal hemoglobin (HbF). The FACS study involved 20 RhD negative pregnant women and 80 RhD negative women after delivery. The following monoclonal antibodies were used: BRAD 3 FITC (anti-RhD antigen), CD45 PerCP (anti leukocyte antigen CD45), and anti-HbF PE. The fluorescence intensity of cells incubated with BRAD 3 FITC was demonstrated to depend on the RhD antigen expression, though the anti-D test also detects the weak D variant. The CD45 PerCP antibodies increased the sensitivity of anti-D test since they eliminated the leukocytes which non-specifically bind anti-D from the analysis. The presence of anti-D antibodies in maternal plasma does not affect the quantitative assessment of the fetal RhD positive fetal cells with BRAD 3 FITC. In case of FMH, the results of the anti-D test were similar to those with anti-HbF antibodies. The flow cytometric test with anti-D and anti-CD45 is useful in the assessment of the fetomaternal hemorrhage in RhD negative women. The sensitivity of the test is estimated at 0.05%.

Regulation of cancer stem cell properties by CD9 in human B-acute lymphoblastic leukemia

Energy Technology Data Exchange (ETDEWEB)

Yamazaki, Hiroto [Division of Clinical Immunology, Advanced Clinical Research Center, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Wilson Xu, C. [Drug Development Program, Nevada Cancer Institute, Las Vegas, NV (United States); Naito, Motohiko [Division of Clinical Immunology, Advanced Clinical Research Center, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Nishida, Hiroko [Division of Hematology, Department of Internal Medicine, Keio University School of Medicine, Tokyo (Japan); Okamoto, Toshihiro; Ghani, Farhana Ishrat; Iwata, Satoshi [Division of Clinical Immunology, Advanced Clinical Research Center, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Inukai, Takeshi; Sugita, Kanji [Department of Pediatrics, School of Medicine, University of Yamanashi, Yamanashi (Japan); Morimoto, Chikao, E-mail: morimoto@ims.u-tokyo.ac.jp [Division of Clinical Immunology, Advanced Clinical Research Center, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Drug Development Program, Nevada Cancer Institute, Las Vegas, NV (United States)

2011-05-27

Highlights: {yields} We performed more detailed analysis of CD9 function for CSC properties in B-ALL. {yields} Leukemogenic fusion/Src family proteins were markedly regulated in the CD9{sup +} cells. {yields} Proliferation of B-ALL cells was inhibited by anti-CD9 monoclonal antibody. {yields} Knockdown of CD9 by RNAi remarkably reduced the leukemogenic potential. {yields} CD9-knockdown affected the expression and phosphorylation of Src family and USP22. -- Abstract: Although the prognosis of acute lymphoblastic leukemia (ALL) has improved considerably in recent years, some of the cases still exhibit therapy-resistant. We have previously reported that CD9 was expressed heterogeneously in B-ALL cell lines and CD9{sup +} cells exhibited an asymmetric cell division with greater tumorigenic potential than CD9{sup -} cells. CD9{sup +} cells were also serially transplantable in immunodeficient mice, indicating that CD9{sup +} cell possess self-renewal capacity. In the current study, we performed more detailed analysis of CD9 function for the cancer stem cell (CSC) properties. In patient sample, CD9 was expressed in the most cases of B-ALL cells with significant correlation of CD34-expression. Gene expression analysis revealed that leukemogenic fusion proteins and Src family proteins were significantly regulated in the CD9{sup +} population. Moreover, CD9{sup +} cells exhibited drug-resistance, but proliferation of bulk cells was inhibited by anti-CD9 monoclonal antibody. Knockdown of CD9 remarkably reduced the leukemogenic potential. Furthermore, gene ablation of CD9 affected the expression and tyrosine-phosphorylation of Src family proteins and reduced the expression of histone-deubiquitinase USP22. Taken together, our results suggest that CD9 links to several signaling pathways and epigenetic modification for regulating the CSC properties of B-ALL.

Relevance analysis and short-term prediction of PM2.5 concentrations in Beijing based on multi-source data

Science.gov (United States)

Ni, X. Y.; Huang, H.; Du, W. P.

2017-02-01

The PM2.5 problem is proving to be a major public crisis and is of great public-concern requiring an urgent response. Information about, and prediction of PM2.5 from the perspective of atmospheric dynamic theory is still limited due to the complexity of the formation and development of PM2.5. In this paper, we attempted to realize the relevance analysis and short-term prediction of PM2.5 concentrations in Beijing, China, using multi-source data mining. A correlation analysis model of PM2.5 to physical data (meteorological data, including regional average rainfall, daily mean temperature, average relative humidity, average wind speed, maximum wind speed, and other pollutant concentration data, including CO, NO2, SO2, PM10) and social media data (microblog data) was proposed, based on the Multivariate Statistical Analysis method. The study found that during these factors, the value of average wind speed, the concentrations of CO, NO2, PM10, and the daily number of microblog entries with key words 'Beijing; Air pollution' show high mathematical correlation with PM2.5 concentrations. The correlation analysis was further studied based on a big data's machine learning model- Back Propagation Neural Network (hereinafter referred to as BPNN) model. It was found that the BPNN method performs better in correlation mining. Finally, an Autoregressive Integrated Moving Average (hereinafter referred to as ARIMA) Time Series model was applied in this paper to explore the prediction of PM2.5 in the short-term time series. The predicted results were in good agreement with the observed data. This study is useful for helping realize real-time monitoring, analysis and pre-warning of PM2.5 and it also helps to broaden the application of big data and the multi-source data mining methods.

Monoclonal TCR-redirected tumor cell killing.

Science.gov (United States)

Liddy, Nathaniel; Bossi, Giovanna; Adams, Katherine J; Lissina, Anna; Mahon, Tara M; Hassan, Namir J; Gavarret, Jessie; Bianchi, Frayne C; Pumphrey, Nicholas J; Ladell, Kristin; Gostick, Emma; Sewell, Andrew K; Lissin, Nikolai M; Harwood, Naomi E; Molloy, Peter E; Li, Yi; Cameron, Brian J; Sami, Malkit; Baston, Emma E; Todorov, Penio T; Paston, Samantha J; Dennis, Rebecca E; Harper, Jane V; Dunn, Steve M; Ashfield, Rebecca; Johnson, Andy; McGrath, Yvonne; Plesa, Gabriela; June, Carl H; Kalos, Michael; Price, David A; Vuidepot, Annelise; Williams, Daniel D; Sutton, Deborah H; Jakobsen, Bent K

2012-06-01

T cell immunity can potentially eradicate malignant cells and lead to clinical remission in a minority of patients with cancer. In the majority of these individuals, however, there is a failure of the specific T cell receptor (TCR)–mediated immune recognition and activation process. Here we describe the engineering and characterization of new reagents termed immune-mobilizing monoclonal TCRs against cancer (ImmTACs). Four such ImmTACs, each comprising a distinct tumor-associated epitope-specific monoclonal TCR with picomolar affinity fused to a humanized cluster of differentiation 3 (CD3)-specific single-chain antibody fragment (scFv), effectively redirected T cells to kill cancer cells expressing extremely low surface epitope densities. Furthermore, these reagents potently suppressed tumor growth in vivo. Thus, ImmTACs overcome immune tolerance to cancer and represent a new approach to tumor immunotherapy.

Monoclonal Antibody Fragments for Targeting Therapeutics to Growth Plate Cartilage | NCI Technology Transfer Center | TTC

Science.gov (United States)

Researchers at The Eunice Kennedy Shriver National Institute on Child Health and Human Development (NICHD) have discovered monoclonal antibodies that bind to matrilin-3, a protein specifically expressed in cartilage tissue, that could be used for treating or inhibiting growth plate disorders, such as a skeletal dysplasia or short stature. The monoclonal antibodies can also be used to target therapeutic agents, such as anti-arthritis agents, to cartilage tissue. NICHD seeks statements of capability or interest from parties interested in collaborative research to co-develop, evaluate, or commercialize treatment of skeletal disorders using targeting antibodies.

Individual and combining effects of anti-RANKL monoclonal antibody and teriparatide in ovariectomized mice

Directory of Open Access Journals (Sweden)

Naoto Tokuyama

2015-06-01

Full Text Available We examined the individual and combined effects of teriparatide and anti-RANKL (receptor activator of nuclear factor κB ligand monoclonal antibody in ovariectomized mice. Three-month-old female C57BL/6 mice were ovariectomized (OVX or sham operated. Four weeks after OVX, they were assigned to 3 different groups to receive anti-RANKL monoclonal antibody (Ab alone (5 mg/kg single injection at 4 weeks after OVX, Ab group, teriparatide alone (80 μg/kg daily injection for 4 weeks from 4 weeks after OVX, PTH group, or mAb plus teriparatide (Ab + PTH group. Mice were sacrificed 8 weeks after OVX. Bone mineral density (BMD was measured at the femur and lumbar spine. Hind limbs were subjected to histological and histomorphometric analysis. Serum osteocalcin and CTX-I levels were measured to investigate the bone turnover. Compared with Ab group, Ab + PTH group showed a significant increase in BMD at distal femur and femoral shaft. Cortical bone volume was significantly increased in PTH and Ab + PTH groups compared with Ab group. Bone turnover in Ab + PTH group was suppressed to the same degree as in Ab group. The number of TRAP-positive multinucleated cells was markedly reduced in Ab and Ab + PTH groups. These results suggest that combined treatment of teriparatide with anti-RANKL antibody has additive effects on BMD in OVX mice compared with individual treatment.

Disseminated Infections with Talaromyces marneffei in Non-AIDS Patients Given Monoclonal Antibodies against CD20 and Kinase Inhibitors

OpenAIRE

Chan, Jasper F.W.; Chan, Thomas S.Y.; Gill, Harinder; Lam, Frank Y.F.; Trendell-Smith, Nigel J.; Sridhar, Siddharth; Tse, Herman; Lau, Susanna K.P.; Hung, Ivan F.N.; Yuen, Kwok-Yung; Woo, Patrick C.Y.

2015-01-01

Infections with the fungus Talaromyces (formerly Penicillium) marneffei are rare in patients who do not have AIDS. We report disseminated T. marneffei infection in 4 hematology patients without AIDS who received targeted therapy with monoclonal antibodies against CD20 or kinase inhibitors during the past 2 years. Clinicians should be aware of this emerging complication, especially in patients from disease-endemic regions.

A novel rabbit anti-hepatocyte growth factor monoclonal neutralizing antibody inhibits tumor growth in prostate cancer cells and mouse xenografts

International Nuclear Information System (INIS)

Yu, Yanlan; Chen, Yicheng; Ding, Guoqing; Wang, Mingchao; Wu, Haiyang; Xu, Liwei; Rui, Xuefang; Zhang, Zhigen

2015-01-01

The hepatocyte growth factor and its receptor c-Met are correlated with castration-resistance in prostate cancer. Although HGF has been considered as an attractive target for therapeutic antibodies, the lack of cross-reactivity of monoclonal antibodies with human/mouse HGFs is a major obstacle in preclinical developments. We generated a panel of anti-HGF RabMAbs either blocking HGF/c-Met interaction or inhibiting c-Met phosphorylation. We selected one RabMAb with mouse cross-reactivity and demonstrated that it blocked HGF-stimulated downstream activation in PC-3 and DU145 cells. Anti-HGF RabMAb inhibited not only the growth of PC-3 cells but also HGF-dependent proliferation in HUVECs. We further demonstrated the efficacy and potency of the anti-HGF RabMAb in tumor xenograft mice models. Through these in vitro and in vivo experiments, we explored a novel therapeutic antibody for advanced prostate cancer. - Highlights: • HGF is an attractive target for castration-refractory prostate cancer. • We generated and characterized a panel of anti-HGF rabbit monoclonal antibodies. • More than half of these anti-HGF RabMAbs was cross-reactive with mouse HGF. • Anti-HGF RabMAb blocks HGF-stimulated phosphorylation and cell growth in vitro. • Anti-HGF RabMAb inhibits tumor growth and angiogenesis in xenograft mice

A novel rabbit anti-hepatocyte growth factor monoclonal neutralizing antibody inhibits tumor growth in prostate cancer cells and mouse xenografts

Energy Technology Data Exchange (ETDEWEB)

Yu, Yanlan; Chen, Yicheng; Ding, Guoqing; Wang, Mingchao; Wu, Haiyang; Xu, Liwei; Rui, Xuefang; Zhang, Zhigen, E-mail: srrshurology@163.com

2015-08-14

The hepatocyte growth factor and its receptor c-Met are correlated with castration-resistance in prostate cancer. Although HGF has been considered as an attractive target for therapeutic antibodies, the lack of cross-reactivity of monoclonal antibodies with human/mouse HGFs is a major obstacle in preclinical developments. We generated a panel of anti-HGF RabMAbs either blocking HGF/c-Met interaction or inhibiting c-Met phosphorylation. We selected one RabMAb with mouse cross-reactivity and demonstrated that it blocked HGF-stimulated downstream activation in PC-3 and DU145 cells. Anti-HGF RabMAb inhibited not only the growth of PC-3 cells but also HGF-dependent proliferation in HUVECs. We further demonstrated the efficacy and potency of the anti-HGF RabMAb in tumor xenograft mice models. Through these in vitro and in vivo experiments, we explored a novel therapeutic antibody for advanced prostate cancer. - Highlights: • HGF is an attractive target for castration-refractory prostate cancer. • We generated and characterized a panel of anti-HGF rabbit monoclonal antibodies. • More than half of these anti-HGF RabMAbs was cross-reactive with mouse HGF. • Anti-HGF RabMAb blocks HGF-stimulated phosphorylation and cell growth in vitro. • Anti-HGF RabMAb inhibits tumor growth and angiogenesis in xenograft mice.

Regulatory function of cytomegalovirus-specific CD4+CD27-CD28- T cells

International Nuclear Information System (INIS)

Tovar-Salazar, Adriana; Patterson-Bartlett, Julie; Jesser, Renee; Weinberg, Adriana

2010-01-01

CMV infection is characterized by high of frequencies of CD27 - CD28 - T cells. Here we demonstrate that CMV-specific CD4 + CD27 - CD28 - cells are regulatory T cells (T R ). CD4 + CD27 - CD28 - cells sorted from CMV-stimulated PBMC of CMV-seropositive donors inhibited de novo CMV-specific proliferation of autologous PBMC in a dose-dependent fashion. Compared with the entire CMV-stimulated CD4 + T-cell population, higher proportions of CD4 + CD27 - CD28 - T R expressed FoxP3, TGFβ, granzyme B, perforin, GITR and PD-1, lower proportions expressed CD127 and PD1-L and similar proportions expressed CD25, CTLA4, Fas-L and GITR-L. CMV-CD4 + CD27 - CD28 - T R expanded in response to IL-2, but not to CMV antigenic restimulation. The anti-proliferative effect of CMV-CD4 + CD27 - CD28 - T R significantly decreased after granzyme B or TGFβ inhibition. The CMV-CD4 + CD27 - CD28 - T R of HIV-infected and uninfected donors had similar phenotypes and anti-proliferative potency, but HIV-infected individuals had higher proportions of CMV-CD4 + CD27 - CD28 - T R . The CMV-CD4 + CD27 - CD28 - T R may contribute to the downregulation of CMV-specific and nonspecific immune responses of CMV-infected individuals.

Anti-CD20 B-cell depletion enhances monocyte reactivity in neuroimmunological disorders

Directory of Open Access Journals (Sweden)

Hohlfeld Reinhard

2011-10-01

Full Text Available Abstract Background Clinical trials evaluating anti-CD20-mediated B-cell depletion in multiple sclerosis (MS and neuromyelitis optica (NMO generated encouraging results. Our recent studies in the MS model experimental autoimmune encephalomyelitis (EAE attributed clinical benefit to extinction of activated B-cells, but cautioned that depletion of naïve B-cells may be undesirable. We elucidated the regulatory role of un-activated B-cells in EAE and investigated whether anti-CD20 may collaterally diminish regulatory B-cell properties in treatment of neuroimmunological disorders. Methods Myelin oligodendrocyte glycoprotein (MOG peptide-immunized C57Bl/6 mice were depleted of B-cells. Functional consequences for regulatory T-cells (Treg and cytokine production of CD11b+ antigen presenting cells (APC were assessed. Peripheral blood mononuclear cells from 22 patients receiving anti-CD20 and 23 untreated neuroimmunological patients were evaluated for frequencies of B-cells, T-cells and monocytes; monocytic reactivity was determined by TNF-production and expression of signalling lymphocytic activation molecule (SLAM. Results We observed that EAE-exacerbation upon depletion of un-activated B-cells closely correlated with an enhanced production of pro-inflammatory TNF by CD11b+ APC. Paralleling this pre-clinical finding, anti-CD20 treatment of human neuroimmunological disorders increased the relative frequency of monocytes and accentuated pro-inflammatory monocyte function; when reactivated ex vivo, a higher frequency of monocytes from B-cell depleted patients produced TNF and expressed the activation marker SLAM. Conclusions These data suggest that in neuroimmunological disorders, pro-inflammatory APC activity is controlled by a subset of B-cells which is eliminated concomitantly upon anti-CD20 treatment. While this observation does not conflict with the general concept of B-cell depletion in human autoimmunity, it implies that its safety and

IL-5 promotes induction of antigen-specific CD4+CD25+ T regulatory cells that suppress autoimmunity.

Science.gov (United States)

Tran, Giang T; Hodgkinson, Suzanne J; Carter, Nicole M; Verma, Nirupama D; Plain, Karren M; Boyd, Rochelle; Robinson, Catherine M; Nomura, Masaru; Killingsworth, Murray; Hall, Bruce M

2012-05-10

Immune responses to foreign and self-Ags can be controlled by regulatory T cells (Tregs) expressing CD4 and IL-2Rα chain (CD25). Defects in Tregs lead to autoimmunity, whereas induction of Ag-specific CD4+CD25+ Tregs restores tolerance. Ag-specific CD4+CD25+ FOXP3+Tregs activated by the T helper type 2 (Th2) cytokine, IL-4, and specific alloantigen promote allograft tolerance. These Tregs expressed the specific IL-5Rα and in the presence of IL-5 proliferate to specific but not third-party Ag. These findings suggest that recombinant IL-5 (rIL-5) therapy may promote Ag-specific Tregs to mediate tolerance. This study showed normal CD4+CD25+ Tregs cultured with IL-4 and an autoantigen expressed Il-5rα. Treatment of experimental autoimmune neuritis with rIL-5 markedly reduced clinical paralysis, weight loss, demyelination, and infiltration of CD4+ (Th1 and Th17) CD8+ T cells and macrophages in nerves. Clinical improvement was associated with expansion of CD4+CD25+FOXP3+ Tregs that expressed Il-5rα and proliferated only to specific autoantigen that was enhanced by rIL-5. Depletion of CD25+ Tregs or blocking of IL-4 abolished the benefits of rIL-5. Thus, rIL-5 promoted Ag-specific Tregs, activated by autoantigen and IL-4, to control autoimmunity. These findings may explain how Th2 responses, especially to parasitic infestation, induce immune tolerance. rIL-5 therapy may be able to induce Ag-specific tolerance in autoimmunity.

Anti-hyperalgesic and anti-inflammatory effects of Achillea santolina and Stachys athorecalyx extracts on complete Freund's adjuvant–induced short- term inflammation in male wistar rats

Directory of Open Access Journals (Sweden)

Elaheh Tekieh

2011-04-01

Full Text Available Introduction: Immune system is involved in the etiology and path physiologic mechanisms of inflammation. Medicinal plants are an important source of substances which are claimed to induce non-specific immune modulator effects. Given the above information and the role of IL-6 in inflammation and pain induction, this study investigated the effects of Achillea santolina and Stachys athorecalyx methanolic and defatted extracts on cmplete Freund's adjuvant (CFA -induced short term inflammation in male Wistar rats Materials and Methods: Inflammation was induced on day zero by CFA injection in hind paw of rats. Methanolic and defatted extractions were prepared form aerial parts of both plants. 50, 100 and 200 mg/kg doses of extracts were selected for IP treatment during 6 days after CFA injection. Results: Results indicated dose related effects of A. santolina and S. athorecalyx extracts on edema, hyperalgesia and serum IL-6 level during inflammation. Although, both methanolic and defatted extracts of S. athorecalyx showed a significant reduction in the inflammatory symptoms, no significant differences was observed between these two kinds of extracts of S.athorecalyx with respect to their anti inflammatory effects. Only methanolic extract of A. santolina was effective during CFA-induced inflammation. Conclusion: These results could suggest that short-term administration of A. santolina and S. athorecalyx extracts possess potent anti-inflammatory effects and modulate paw edema, hyperalgesia and serum IL-6 level during CFA–induced inflammation. In addition, these dose-dependent effects may mediate via different extract supplements which need more investigations.

Virus-induced dysfunction of CD4+CD25+ T cells in patients with HTLV-I-associated neuroimmunological disease.

Science.gov (United States)

Yamano, Yoshihisa; Takenouchi, Norihiro; Li, Hong-Chuan; Tomaru, Utano; Yao, Karen; Grant, Christian W; Maric, Dragan A; Jacobson, Steven

2005-05-01

CD4(+)CD25(+) Tregs are important in the maintenance of immunological self tolerance and in the prevention of autoimmune diseases. As the CD4(+)CD25(+) T cell population in patients with human T cell lymphotropic virus type I-associated (HTLV-I-associated) myelopathy/tropical spastic paraparesis (HAM/TSP) has been shown to be a major reservoir for this virus, it was of interest to determine whether the frequency and function of CD4(+)CD25(+) Tregs in HAM/TSP patients might be affected. In these cells, both mRNA and protein expression of the forkhead transcription factor Foxp3, a specific marker of Tregs, were lower than those in CD4(+)CD25(+) T cells from healthy individuals. The virus-encoded transactivating HTLV-I tax gene was demonstrated to have a direct inhibitory effect on Foxp3 expression and function of CD4(+)CD25(+) T cells. This is the first report to our knowledge demonstrating the role of a specific viral gene product (HTLV-I Tax) on the expression of genes associated with Tregs (in particular, foxp3) resulting in inhibition of Treg function. These results suggest that direct human retroviral infection of CD4(+)CD25(+) T cells may be associated with the pathogenesis of HTLV-I-associated neurologic disease.

Clinical trials with rasagiline: evidence for short-term and long-term effects.

Science.gov (United States)

Siderowf, Andrew; Stern, Matthew

2006-05-23

Rasagiline (N-propargyl-1 (R)-aminoindan) is a selective, potent irreversible inhibitor of MAO-B that possesses neuroprotective and anti-apoptotic properties in a variety of in vitro and in vivo animal models relevant to Parkinson's disease (PD). Several randomized controlled clinical trials have demonstrated the safety and efficacy of rasagiline as monotherapy in PD and as adjunctive therapy for patients receiving levodopa. In addition, the 1-year randomized, delayed-start analysis of the TEMPO study suggests that rasagiline may slow the rate of progression of PD. The randomized delayed-start paradigm has potential to differentiate short-term symptomatic effects from long-term effects of anti-parkinsonian agents. In the future, long-term trials to examine the potential disease-modifying effects of rasagiline, which incorporate biological markers as well as clinical endpoints, may further elucidate the role of rasagiline in the treatment of both early and advanced PD.

{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)

Effect of producer cell line on functional activity of anti-D monoclonal antibodies destined for prevention of rhesus sensitization.

Science.gov (United States)

Olovnikova, N I; Ershler, M A; Belkina, E V; Nikolaeva, T L; Miterev, G Yu

2009-04-01

The ability of anti-D antibodies to cause antigen-specific immunosuppression depends on their interaction with low-affinity Fcgamma-receptors. Human monoclonal antibodies to D antigen of the rhesus system were investigated by antibody-dependent cytotoxicity assay in order to estimate their ability to induce hemolysis mediated by low-affinity Fcgamma receptors. We demonstrate that affinity of monoclonal antibodies to receptors of this type does not depend on primary structure of Fc-fragment, but depends on the producer cell line which expresses the antibodies. Monoclonal IgG1 antibodies interacting with FcgammaRIIa and FcgammaRIII lost this property, if they were secreted by human-mouse heterohybridoma, but not by human B-cell line. On the opposite, monoclonal antibodies that could not activate low-affinity Fcgamma receptors were highly active after human cells fusion with rat myeloma YB2/0. Hemolytic activity of IgG3 remained unchanged after fusion of human cells with rodent cells.

CD40–CD40 Ligand Pathway Is a Major Component of Acute Neuroinflammation and Contributes to Long-term Cognitive Dysfunction after Sepsis

Science.gov (United States)

Michels, Monique; Danieslki, Lucinéia Gainski; Vieira, Andriele; Florentino, Drielly; Dall’Igna, Dhébora; Galant, Letícia; Sonai, Beatriz; Vuolo, Francieli; Mina, Franciele; Pescador, Bruna; Dominguini, Diogo; Barichello, Tatiana; Quevedo, João; Dal-Pizzol, Felipe; Petronilho, Fabrícia

2015-01-01

Sepsis-associated encephalopathy (SAE) is associated with an increased rate of morbidity and mortality. It is not understood what the exact mechanism is for the brain dysfunction that occurs in septic patients, but brain inflammation and oxidative stress are a possible theory. Such events can occur through the alteration of molecules that perpetuate the inflammatory response. Thus, it is possible to postulate that CD40 may be involved in this process. The aim of this work is to evaluate the role of CD40–CD40L pathway activation in brain dysfunction associated with sepsis in an animal model. Microglia activation induces the upregulation of CD40–CD40L, both in vitro and in vivo. The inhibition of microglia activation decreases levels of CD40–CD40L in the brain and decreases brain inflammation, oxidative damage and blood brain barrier dysfunction. Despite this, anti-CD40 treatment does not improve mortality in this model. However, it is able to improve long-term cognitive impairment in sepsis survivors. In conclusion, there is a major involvement of the CD40–CD40L signaling pathway in long-term brain dysfunction in an animal model of sepsis. PMID:25822797

The in vivo mechanism of action of CD20 monoclonal antibodies depends on local tumor burden

Science.gov (United States)

Boross, Peter; Jansen, J.H. Marco; de Haij, Simone; Beurskens, Frank J.; van der Poel, Cees E.; Bevaart, Lisette; Nederend, Maaike; Golay, Josée; van de Winkel, Jan G.J.; Parren, Paul W.H.I.; Leusen, Jeanette H.W.

2011-01-01

Background CD20 monoclonal antibodies are widely used in clinical practice. Antibody-dependent cellular cytotoxicity, complement-dependent cytotoxicity and direct cell death have been suggested to be important effector functions for CD20 antibodies. However, their specific contributions to the in vivo mechanism of action of CD20 immunotherapy have not been well defined. Design and Methods Here we studied the in vivo mechanism of action of type I (rituximab and ofatumumab) and type II (HuMab-11B8) CD20 antibodies in a peritoneal, syngeneic, mouse model with EL4-CD20 cells using low and high tumor burden. Results Interestingly, we observed striking differences in the in vivo mechanism of action of CD20 antibodies dependent on tumor load. In conditions of low tumor burden, complement was sufficient for tumor killing both for type I and type II CD20 antibodies. In contrast, in conditions of high tumor burden, activating FcγR (specifically FcγRIII), active complement and complement receptor 3 were all essential for tumor killing. Our data suggest that complement-enhanced antibody-dependent cellular cytotoxicity may critically affect tumor killing by CD20 antibodies in vivo. The type II CD20 antibody 11B8, which is a poor inducer of complement activation, was ineffective against high tumor burden. Conclusions Tumor burden affects the in vivo mechanism of action of CD20 antibodies. Low tumor load can be eliminated by complement alone, whereas elimination of high tumor load requires multiple effector mechanisms. PMID:21880632

Pretransplant soluble CD30 serum concentration does not affect kidney graft outcomes 3 years after transplantation.

Science.gov (United States)

Kovač, J; Arnol, M; Vidan Jeras, B; Bren, A F; Kandus, A

2010-12-01

An elevated serum concentration of soluble the form of CD30 (sCD30), an activation marker of mainly T(H)2-type cytokines producing T lymphocytes, has been reported as a predictive factor for acute cellular rejection episodes and poor graft outcomes in kidney transplantation. This historic cohort study investigated the association of a pretransplant sCD30 serum concentrations with kidney graft function and graft survival 3 years posttransplantation in adult recipients of deceased donor kidney grafts, treated with monoclonal anti-CD25 antibodies as an induction treatment combined with a cyclosporine (CsA)-based maintenance triple therapy. The pretransplant sera of 296 recipients were tested for sCD30 content using a microsphere flow-cytometry assay. The estimated glomerular filtration rate (eGFR) was determined by the 4-variable Modification of Diet in Renal Disease equation. The incidences of graft loss were calculated with the use of Kaplan-Meier survival analysis and compared using the log-rank test. According to the distribution of the pretransplant sCD30 levels concentration ≥2700 pg/mL was defined as high (n = 146) and concentration sCD30 groups (65 ± 24 vs 67 ± 21 mL/min/1.73 m(2); P = .43); there was no association between the eGFR 3 years after transplantation and the pretransplant sCD30 levels (r(2) = 0.002; P = .49). Graft survival 3 years after transplantation was also not different in the recipients in high and low sCD30 groups (P = .52). In our adult deceased-donor kidney graft recipients, the pretransplant sCD30 serum concentration was not a predictive factor of immunologic risk associated with the kidney graft function 3 years posttransplantation; neither did it affect graft survival 3 years after transplantation. The immunosuppression with anti-CD25 antibodies as an induction treatment combined with the CsA-based maintenance triple therapy could possibly be decisive for our findings. Copyright © 2010 Elsevier Inc. All rights reserved.

Characterization of a lipopolysaccharide mutant of Leptospira derived by growth in the presence of an anti-lipopolysaccharide monoclonal antibody

NARCIS (Netherlands)

Zapata, Sonia; Trueba, Gabriel; Bulach, Dieter M.; Boucher, David; Adler, Ben; Hartskeerl, Rudy

2010-01-01

A lipopolysaccharide mutant of Leptospira interrogans (LaiMut) was obtained by growth in the presence of an agglutinating monoclonal antibody (mAb) against lipopolysaccharide. Agglutination reactions with anti-lipopolysaccharide mAbs and polyclonal antibodies showed that LaiMut had lost some

CD4+CD25+ regulatory T cells control CD8+ T-cell effector differentiation by modulating IL-2 homeostasis

Science.gov (United States)

McNally, Alice; Hill, Geoffrey R.; Sparwasser, Tim; Thomas, Ranjeny; Steptoe, Raymond J.

2011-01-01

CD4+CD25+ regulatory T cells (Treg) play a crucial role in the regulation of immune responses. Although many mechanisms of Treg suppression in vitro have been described, the mechanisms by which Treg modulate CD8+ T cell differentiation and effector function in vivo are more poorly defined. It has been proposed, in many instances, that modulation of cytokine homeostasis could be an important mechanism by which Treg regulate adaptive immunity; however, direct experimental evidence is sparse. Here we demonstrate that CD4+CD25+ Treg, by critically regulating IL-2 homeostasis, modulate CD8+ T-cell effector differentiation. Expansion and effector differentiation of CD8+ T cells is promoted by autocrine IL-2 but, by competing for IL-2, Treg limit CD8+ effector differentiation. Furthermore, a regulatory loop exists between Treg and CD8+ effector T cells, where IL-2 produced during CD8+ T-cell effector differentiation promotes Treg expansion. PMID:21502514

Differences between primed allogeneic T-cell responses and the primary mixed leucocyte reaction. Primed T cells become independent of the blocking effects of monoclonal antibodies against IL-1 beta and the CD5, CD11a (LFA-1), and CD11c (p 150,95) molecules

DEFF Research Database (Denmark)

Ødum, Niels; Hofmann, B; Morling, N

1988-01-01

.01) and the purified protein derivative (PPD) induced lymphocyte transformation response (42%, P less than or equal to 0.01) of peripheral blood mononuclear cells (PBMC), whereas primed allogeneic responses to PBMC and Epstein-Barr virus (EBV) cell lines were unaffected by this MoAb. In addition, preliminary data...... monoclonal antibodies (MoAb) directed against (i) adhesion molecules belonging to the CD11 cluster of leucocyte antigens (CD11a, LFA-1; CD11b, MAC1 = CR3; and CD11c, p 150,95); (ii) various T cell-related antigens (CD2, CD4, CD5 and CD8); and (iii) recombinant IL-1 beta. The CD5-, CD11a- and CD11c...

Structuring spot, short and long term gas contracts; CD-ROM ed.

Energy Technology Data Exchange (ETDEWEB)

Gretener, N.M.

1996-05-01

A review of the core clauses of the modern natural gas purchase and sales contracts, was presented. There exists a wide variety of terms which can be used by a seller and a buyer to customize such a contract to suit particular circumstances. On the basis of length of term, gas contracts may classified as spot contracts having a term of 30 days or less, short term contracts having a term of 30 days to one to two years, and long term contracts having terms greater than two years. The three key elements which are applicable to all gas sales contracts are the contract price, the seller`s obligation to deliver, and the buyer`s obligation to accept. Other provisions that may be included in any gas sales contract in addition to the basic three were reviewed, including market pricing, load factor incentive pricing, seasonal pricing, pipeline demand charges, market shares, and the seller`s right to decontract.

High soluble CD30, CD25 and IL-6 may identify patients with worse survival in CD30+ cutaneous lymphomas and early mycosis fungoides

Science.gov (United States)

Kadin, Marshall E.; Pavlov, Igor; Delgado, Julio C.; Vonderheid, Eric C.

2011-01-01

Histopathology alone cannot predict outcome of patients with CD30+ primary cutaneous lymphoproliferative disorders (CD30CLPD) and early mycosis fungoides (MF). To test the hypothesis that serum cytokines/cytokine receptors provide prognostic information in these disorders, we measured soluble CD30 (sCD30), sCD25, and selected cytokines in cell cultures and sera of 116 patients with CD30CLPD and 96 patients with early MF followed up to 20 years. Significant positive correlation was found between sCD30 levels and sCD25, CD40L, IL-6, and IL-8, suggesting CD30+ neoplastic cells secrete these cytokines, but not Th2 cytokines. In vitro studies confirmed sCD30, sCD25, IL-6 and IL-8 are secreted by CD30CLPD-derived cell lines. CD30CLPD patients with above normal sCD30 and sCD25 had worse overall and disease-related survivals, but only sCD30 retained significance in Cox models that included advanced age. High sCD30 also identified patients with worse survival in early MF. Increased IL-6 and IL-8 correlated with poor disease-related survival in CD30CLPD patients, We conclude that: (1) neoplastic cells of some CD30CLPD patients do not resemble Th2 cells, (2) high serum sCD30, sCD25, IL-6, and perhaps IL-8 levels may provide prognostic information useful for patient management. PMID:22071475

PENGARUH KEDALAMAN AIR TERHADAP SHORT TERM MEMORY DAN KONSUMSI ENERGI PADA PENYELAM

Directory of Open Access Journals (Sweden)

Rini Dharmastiti

2012-02-01

Full Text Available Penelitian ini akan melihat pengaruh kedalaman air terhadap short term memory dan konsumsi energi penyelam. Penelitian ini mengambil sampel 10 mahasiswa pria dan 5 wanita. Pengukuran performansi short term memory dilakukan dengan cara setiap obyek diperlihatkan deretan 7 angka acak yang diberikan selama 5 detik dan setelah 15 detik kemudian dilakukan pemanggilan kembali informasi yang baru saja diberikan. Setiap obyek diuji sebangak 30 kali untuk setiap kedalaman (1 m; 2,5 m; dan 4 m. Pengukuran konsumsi energi dilakukan dengan menghitung denyut jantung menggunakan metode palpasi. Hasil penelitian menunjukkan bahwa semakin meningkat kedalaman air, maka performasi short term memory penyelam tersebut semakin menurun.  Penurunan ini berlaku untuk pria dan wanita. Penambahan kedalaman ini juga meningkatkan konsumsi energi baik pada pria maupun wanita. Perbedaan jenis kelamin mempengaruhi performansi short term memory secara signifikan. Pria memiliki performansi rata-rata short term memory sebesar 91,67% pada kedalaman 1 m, 90,67% pada kedalaman 2,5 m, dan 86,33% pada kedalaman 4 m. Sedangkan wanita memiliki performansi rata-rata sebesar 86% pada kedalaman 1 m, 84% pada kedalaman 2,5 m, dan 80,67% pada kedalaman 4 m. Rata-rata konsumsi energi pria adalah 3,19 kkal, 3,34 kkal, dan 3,65 kkal pada kedalaman 1 m; 2,5 m; dan 4 m berturut-turut. Sedangkan rata-rata konsumsi energi wanita adalah 3,81 kkal, 4,07 kkal, dan 4,54 kkal pada kedalaman yang sama dengan pria.     Kata kunci : tekanan, kedalaman air, performansi short term memory, konsumsi energi.       This research is to observe water depth effects on short term memory and energy expenditure of diver. This research objects are 10 male and 5 female students. Short term memory performance measurement held by every object has been shown 7 random numerics (as information for 5 seconds and after 15 seconds later they write down the information on a paper. Every object got 30 tests for every

CD25, CD28 and CD38 expression in peripheral blood lymphocytes as a tool to predict acute rejection after liver transplantation.

Science.gov (United States)

Boleslawski, Emmanuel; BenOthman, Samia; Grabar, Sophie; Correia, Leonor; Podevin, Philippe; Chouzenoux, Sandrine; Soubrane, Olivier; Calmus, Yvon; Conti, Filomena

2008-01-01

The aim of this study was to determine whether the expression of CD25, CD28 and CD38 (which reflects the degree of T-cell activation) by peripheral blood mononuclear cells constitutes a useful means of measuring the immune status of liver transplant recipients. Fifty-two patients enrolled in a prospective randomized study comparing cyclosporine and tacrolimus as the principal immunosuppressive drugs were monitored prospectively. The expression of CD25, CD28 and CD38 was analyzed on CD3-, CD4- and CD8-positive cells from whole blood using flow cytometry. The prognostic value of baseline and day 14 measurements regarding acute rejection was examined using Kaplan-Meier estimates for univariate analyses and the Cox model for multivariate analyses. The mean frequencies of CD28 and CD38-expressing T cells were significantly higher in patients with acute rejection (p = 0.01 and p = 0.001, respectively), whereas the frequency CD25-expressing T cells did not differ significantly. Under univariate analysis, baseline CD25 levels, the type of calcineurin inhibitor, as well as the CD28 and CD38 frequencies obtained at day 14 were associated with the subsequent development of acute rejection. Under multivariate analysis, only CD28 and CD38 frequencies obtained at day 14 were independently associated with acute rejection. The evaluation of CD28 and CD38 expression in peripheral blood lymphocytes is a simple marker that could be used routinely in clinical practice to assess the level of immunosuppression.

Slow desensitization of imatinib-induced nonimmediate reactions and dynamic changes of drug-specific CD4+CD25+CD134+ lymphocytes.

Science.gov (United States)

Klaewsongkram, Jettanong; Thantiworasit, Pattarawat; Sodsai, Pimpayao; Buranapraditkun, Supranee; Mongkolpathumrat, Pungjai

2016-11-01

Imatinib is a tyrosine kinase inhibitor indicated for the treatment of gastrointestinal stromal tumors (GISTs) and certain neoplastic diseases; however, nonimmediate adverse reactions are common. To describe the process of imatinib slow desensitization in patients who experienced nonimmediate reactions to imatinib and the dynamic change in drug-specific CD4 + CD25 + CD134 + T-lymphocyte percentages. Five patients diagnosed as having GISTs and with a recent history of imatinib-induced nonimmediate reactions (maculopapular exanthema with eosinophilia, exfoliative dermatitis, palmar-plantar erythrodysesthesia, and drug rash with eosinophilia and systemic symptoms) were desensitized using a slow desensitization protocol. The reintroduced imatinib dosage was stepped up every week starting from 10 mg/d and increasing to 25, 50, 75, 100, 150, 200, and 300 mg/d until the target dose of 400 mg/d was achieved. Prednisolone of up to 30 mg/d was allowed if allergic reactions recurred. The percentages of CD4 + CD25 + CD134 + T cells present after incubating peripheral blood mononuclear cells with imatinib, at baseline and after successful desensitization, were analyzed using flow cytometric analysis. By using a slow desensitization technique, all patients were able to receive 400 mg/d of imatinib, and prednisolone was gradually tapered off. The percentages of imatinib-induced CD4 + CD25 + CD134 + T cells decreased from a mean (SD) of 11.3% (6.5%) and 13.4% (7.3%) at baseline to 3.2% (0.7%) and 3.0% (1.1%) after successful desensitization, when stimulating peripheral blood mononuclear cells with 1 and 2 μM of imatinib, respectively. Slow desensitization is a helpful procedure in treating patients with imatinib-induced nonimmediate reactions other than simple maculopapular exanthema. The reduced percentages of imatinib-induced CD4 + CD25 + CD134 + T cells in these patients may be associated with immune tolerance. Copyright © 2016 American College of Allergy, Asthma & Immunology

Micrometastatic cancer cells in bone marrow: in vitro detection with anti-cytokeratin and in vivo labeling with anti-17-1A monoclonal antibodies

International Nuclear Information System (INIS)

Schlimok, G.; Funke, I.; Holzmann, B.

1987-01-01

The detection of early micrometastasis or disseminated single tumor cells poses a problem for conventional diagnosis procedures. Using a panel of monoclonal antibodies against cytokeratin and the 17-1A epithelial antigen the authors identified immunocytochemically tumor cells in bone marrow of patients with breast cancer and colorectal cancer at the time of surgery of the primary tumor. Monoclonal antibody CK2, recognizing the human cytokeratin component 18 in simple epithelia, appeared to be the most suitable reagent because of its negative reaction with bone marrow samples of the noncarcinoma patients. Its specificity was further demonstrated in a double-marker staining procedure using an anti-leukocyte common antigen monoclonal antibody (T200) as counterstain. A comparative analysis showed that immunocytology was clearly superior to conventional cytology and histology. In 9.5-20.5% of patients without distant metastasis, tumor cells could be detected in bone marrow. They found a significant correlation between tumor cells in bone marrow and conventional risk factors, such as distant metastasis or lymph node involvement. In a first approach toward immunotherapy they demonstrated in 3 patients that infused monoclonal antibody 17-1A can label single tumor cells in bone marrow in vivo. They then used this single approach to follow up on 7 patients undergoing 17-1A therapy in an adjuvant clinical trial

Therapeutic effect of anti-feline TNF-alpha monoclonal antibody for feline infectious peritonitis.

Science.gov (United States)

Doki, Tomoyoshi; Takano, Tomomi; Kawagoe, Kohei; Kito, Akihiko; Hohdatsu, Tsutomu

2016-02-01

Feline infectious peritonitis virus (FIPV) replication in macrophages/monocytes induced tumor necrosis factor (TNF)-alpha production, and that the TNF-alpha produced was involved in aggravating the pathology of FIP. We previously reported the preparation of a feline TNF-alpha (fTNF-alpha)-neutralizing mouse monoclonal antibody (anti-fTNF-alpha mAb). This anti-fTNF-alpha mAb 2-4 was confirmed to inhibit the following fTNF-alpha-induced conditions in vitro. In the present study, we investigated whether mAb 2-4 improved the FIP symptoms and survival rate of experimentally FIPV-inoculated SPF cats. Progression to FIP was prevented in 2 out of 3 cats treated with mAb 2-4, whereas all 3 cats developed FIP in the placebo control group. Plasma alpha1-glycoprotein and vascular endothelial growth factor levels were improved by the administration of mAb 2-4, and the peripheral lymphocyte count also recovered. These results strongly suggested that the anti-fTNF-alpha antibody is effective for the treatment of FIP. Copyright © 2015 Elsevier Ltd. All rights reserved.

Radioimmunodetection of colorectal cancer, using anti-CEA monoclonal antibodies

International Nuclear Information System (INIS)

Murayama, Hiroki; Watanabe, Tadashi; Tadokoro, Masanori; Takagi, Hiroshi; Sakuma, Sadayuki; Sakamoto, Junichi.

1989-01-01

Aiming at radioimmunodetection of colorectal cancer, anti-CEA monoclonal antibodies (CEA102) were produced by immunization with purified CEA. CEA102 showed high specificity with clorectal cancer by mixed hemadsorption assay and immunoperoxidase technique. The antigen detected by CEA102 was confirmed to be carcinoembryonic antigen (CEA) and its molecular weight was estimated to be ca. 180,000 by biochemical analysis. The in vivo study using nude mice grafted a human colorectal cancer or a human malignant melanoma showed greater accumulation of 125 I-labeled CEA102 in CEA-positive colorectal cancer than in nude mouse tissues and CEA-negative malignant melanoma. Moreover we successfully obtained scans with good localization of the grafted colorectal cancer on FCR (Fuji Computed Radiography). Using 131 I-labeled CEA102 liver metastasis in the patient with colorectal cancer was successfully detected by external scanning with γ-camera. These results suggest that radiolabeled CEA102 is useful for the detection of colorectal cancer. (author)

CD 4 + CD 25 + T cells maintain homeostasis by promoting TER - 119 cell development and inhibiting T cell activation

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Muhaimin Rifa’i

2014-05-01

Full Text Available CD4+ CD25+ regulatory T cells involved in the regulation of self- tolerance and normality of homeostasis. CD122 deficient mice are model animals that have an abnormal immune system characteristically have a high number of activated T cells and TER-119 cell decreased. Here we showed evidence that the transfer of CD4+ CD25+ regulatory T cells derived from normal mice to CD122- defficient neonates prevent the development of activated memory T cells and elicit TER-119 differentiation. Bone marrow reconstitution derived from CD122-/- mice to normal mice resulting tolerance to individual that genetically different. Importantly, CD4+ CD25+ regulatory T cells derived from normal mice can replace CD4+ CD25+ cells derived from CD122-/- mice. The results of this experiment suggest that regulatory T cells from normal mice exert a critical role in maintaining peripheral tolerance and controlling hematopoietic disorder.

Memory B cells and CD8⁺ lymphocytes do not control seasonal influenza A virus replication after homologous re-challenge of rhesus macaques.

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Timothy D Carroll

Full Text Available This study sought to define the role of memory lymphocytes in the protection from homologous influenza A virus re-challenge in rhesus macaques. Depleting monoclonal antibodies (mAb were administered to the animals prior to their second experimental inoculation with a human seasonal influenza A virus strain. Treatment with either anti-CD8α or anti-CD20 mAbs prior to re-challenge had minimal effect on influenza A virus replication. Thus, in non-human primates with pre-existing anti-influenza A antibodies, memory B cells and CD8α⁺ T cells do not contribute to the control of virus replication after re-challenge with a homologous strain of influenza A virus.

Broad, Intense Anti-Human Immunodeficiency Virus (HIV) Ex Vivo CD8+ Responses in HIV Type 1-Infected Patients: Comparison with Anti-Epstein-Barr Virus Responses and Changes during Antiretroviral Therapy

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Dalod, Marc; Dupuis, Marion; Deschemin, Jean-Christophe; Sicard, Didier; Salmon, Dominique; Delfraissy, Jean-Francois; Venet, Alain; Sinet, Martine; Guillet, Jean-Gerard

1999-01-01

The ex vivo antiviral CD8+ repertoires of 34 human immunodeficiency virus (HIV)-seropositive patients with various CD4+ T-cell counts and virus loads were analyzed by gamma interferon enzyme-linked immunospot assay, using peptides derived from HIV type 1 and Epstein-Barr virus (EBV). Most patients recognized many HIV peptides, with markedly high frequencies, in association with all the HLA class I molecules tested. We found no correlation between the intensity of anti-HIV CD8+ responses and the CD4+ counts or virus load. In contrast, the polyclonality of anti-HIV CD8+ responses was positively correlated with the CD4+ counts. The anti-EBV responses were significantly less intense than the anti-HIV responses and were positively correlated with the CD4+ counts. Longitudinal follow-up of several patients revealed the remarkable stability of the anti-HIV and anti-EBV CD8+ responses in two patients with stable CD4+ counts, while both antiviral responses decreased in two patients with obvious progression toward disease. Last, highly active antiretroviral therapy induced marked decreases in the number of anti-HIV CD8+ T cells, while the anti-EBV responses increased. These findings emphasize the magnitude of the ex vivo HIV-specific CD8+ responses at all stages of HIV infection and suggest that the CD8+ hyperlymphocytosis commonly observed in HIV infection is driven mainly by virus replication, through intense, continuous activation of HIV-specific CD8+ T cells until ultimate progression toward disease. Nevertheless, highly polyclonal anti-HIV CD8+ responses may be associated with a better clinical status. Our data also suggest that a decrease of anti-EBV CD8+ responses may occur with depletion of CD4+ T cells, but this could be restored by highly active antiretroviral treatment. PMID:10438796

Clinical significance of BRAF non-V600E mutations on the therapeutic effects of anti-EGFR monoclonal antibody treatment in patients with pretreated metastatic colorectal cancer: the Biomarker Research for anti-EGFR monoclonal Antibodies by Comprehensive Cancer genomics (BREAC) study.

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Shinozaki, Eiji; Yoshino, Takayuki; Yamazaki, Kentaro; Muro, Kei; Yamaguchi, Kensei; Nishina, Tomohiro; Yuki, Satoshi; Shitara, Kohei; Bando, Hideaki; Mimaki, Sachiyo; Nakai, Chikako; Matsushima, Koutatsu; Suzuki, Yutaka; Akagi, Kiwamu; Yamanaka, Takeharu; Nomura, Shogo; Fujii, Satoshi; Esumi, Hiroyasu; Sugiyama, Masaya; Nishida, Nao; Mizokami, Masashi; Koh, Yasuhiro; Abe, Yukiko; Ohtsu, Atsushi; Tsuchihara, Katsuya

2017-11-07

Patients with BRAF V600E -mutated metastatic colorectal cancer (mCRC) have a poorer prognosis as well as resistance to anti-EGFR antibodies. However, it is unclear whether BRAF mutations other than BRAF V600E (BRAF non-V600E mutations) contribute to anti-EGFR antibody resistance. This study was composed of exploratory and inference cohorts. Candidate biomarkers identified by whole exome sequencing from super-responders and nonresponders in the exploratory cohort were validated by targeted resequencing for patients who received anti-EGFR antibody in the inference cohort. In the exploratory cohort, 31 candidate biomarkers, including KRAS/NRAS/BRAF mutations, were identified. Targeted resequencing of 150 patients in the inference cohort revealed 40 patients with RAS (26.7%), 9 patients with BRAF V600E (6.0%), and 7 patients with BRAF non-V600E mutations (4.7%), respectively. The response rates in RAS, BRAF V600E , and BRAF non-V600E were lower than those in RAS/BRAF wild-type (2.5%, 0%, and 0% vs 31.9%). The median PFS in BRAF non-V600E mutations was 2.4 months, similar to that in RAS or BRAF V600E mutations (2.1 and 1.6 months) but significantly worse than that in wild-type RAS/BRAF (5.9 months). Although BRAF non-V600E mutations identified were a rare and unestablished molecular subtype, certain BRAF non-V600E mutations might contribute to a lesser benefit of anti-EGFR monoclonal antibody treatment.

The effectiveness of the anti-CD11d treatment is reduced in rat models of spinal cord injury that produce significant levels of intraspinal hemorrhage.

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Geremia, N M; Hryciw, T; Bao, F; Streijger, F; Okon, E; Lee, J H T; Weaver, L C; Dekaban, G A; Kwon, B K; Brown, A

2017-09-01

We have previously reported that administration of a CD11d monoclonal antibody (mAb) improves recovery in a clip-compression model of SCI. In this model the CD11d mAb reduces the infiltration of activated leukocytes into the injured spinal cord (as indicated by reduced intraspinal MPO). However not all anti-inflammatory strategies have reported beneficial results, suggesting that success of the CD11d mAb treatment may depend on the type or severity of the injury. We therefore tested the CD11d mAb treatment in a rat hemi-contusion model of cervical SCI. In contrast to its effects in the clip-compression model, the CD11d mAb treatment did not improve forelimb function nor did it significantly reduce MPO levels in the hemi-contused cord. To determine if the disparate results using the CD11d mAb were due to the biomechanical nature of the cord injury (compression SCI versus contusion SCI) or to the spinal level of the injury (12th thoracic level versus cervical) we further evaluated the CD11d mAb treatment after a T12 contusion SCI. In contrast to the T12 clip compression SCI, the CD11d mAb treatment did not improve locomotor recovery or significantly reduce MPO levels after T12 contusion SCI. Lesion analyses revealed increased levels of hemorrhage after contusion SCI compared to clip-compression SCI. SCI that is accompanied by increased intraspinal hemorrhage would be predicted to be refractory to the CD11d mAb therapy as this approach targets leukocyte diapedesis through the intact vasculature. These results suggest that the disparate results of the anti-CD11d treatment in contusion and clip-compression models of SCI are due to the different pathophysiological mechanisms that dominate these two types of spinal cord injuries. Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.

Relationship of the Content of Systemic and Endobronchial Soluble Molecules of CD25, CD38, CD8, and HLA-I-CD8 and Lung Function Parameters in COPD Patients

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Nailya Kubysheva

2017-01-01

Full Text Available The definition of new markers of local and systemic inflammation of chronic obstructive pulmonary disease (COPD is one of the priority directions in the study of pathogenesis and diagnostic methods improvement for this disease. We investigated 91 patients with COPD and 21 healthy nonsmokers. The levels of soluble CD25, CD38, CD8, and HLA-I-CD8 molecules in the blood serum and exhaled breath condensate (EBC in moderate-to-severe COPD patients during exacerbation and stable phase were studied. An unidirectional change in the content of sCD25, sCD38, and sCD8 molecules with increasing severity of COPD was detected. The correlations between the parameters of lung function and sCD8, sCD25, and sHLA-I-CD8 levels in the blood serum and EBC were discovered in patients with severe COPD. The findings suggest a pathogenetic role of the investigated soluble molecules of the COPD development and allow considering the content of sCD8, sCD25, and sHLA-I-CD8 molecules as additional novel systemic and endobronchial markers of the progression of chronic inflammation of this disease.

Anti-PD-1 Blockade and Stereotactic Radiation Produce Long-Term Survival in Mice With Intracranial Gliomas

International Nuclear Information System (INIS)

Zeng, Jing; See, Alfred P.; Phallen, Jillian; Jackson, Christopher M.; Belcaid, Zineb; Ruzevick, Jacob; Durham, Nicholas; Meyer, Christian; Harris, Timothy J.; Albesiano, Emilia; Pradilla, Gustavo; Ford, Eric; Wong, John; Hammers, Hans-Joerg; Mathios, Dimitris; Tyler, Betty; Brem, Henry; Tran, Phuoc T.; Pardoll, Drew; Drake, Charles G.

2013-01-01

Purpose: Glioblastoma multiforme (GBM) is the most common primary brain tumor in adults, and radiation is one of the main treatment modalities. However, cure rates remain low despite best available therapies. Immunotherapy is a promising modality that could work synergistically with radiation, which has been shown to increase antigen presentation and promote a proinflammatory tumor microenvironment. Programmed-death-1 (PD-1) is a surface receptor expressed on activated and exhausted T cells, which mediate T cell inhibition upon binding with its ligand PD-L1, expressed on many tumor types including human GBMs. We tested the combination of anti-PD-1 immunotherapy with stereotactic radiosurgery in a mouse orthotopic GBM model. Methods and Materials: We performed intracranial implantation of mouse glioma cell line GL261 transfected with luciferase into C57BL/6 mice. Mice were stratified into 4 treatment groups: (1) control; (2) radiation only; (3) anti-PD-1 antibody only; and (4) radiation plus anti-PD-1 antibody. Overall survival was quantified. The mice were killed on day 21 after implantation to assess immunologic parameters in the brain/tumor, cervical lymph nodes, and spleen. Results: Improved survival was demonstrated with combination anti-PD-1 therapy plus radiation compared with either modality alone: median survival was 25 days in the control arm, 27 days in the anti-PD-1 antibody arm, 28 days in the radiation arm, and 53 days in the radiation plus anti-PD-1 therapy arm (P<.05 by log-rank Mantle-Cox). Long-term survival was seen only in the combined treatment arm, with a fraction (15%-40%) of animals alive at day 180+ after treatment. Immunologic data on day 21 after implantation showed increased tumor infiltration by cytotoxic T cells (CD8+/interferon-γ+/tumor necrosis factor-α+) and decreased regulatory T cells (CD4+/FOXP3) in the combined treatment group compared with the single modality arms. Conclusions: The combination of PD-1 blockade and localized

Anti-PD-1 Blockade and Stereotactic Radiation Produce Long-Term Survival in Mice With Intracranial Gliomas

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Zeng, Jing [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins Medical Institutes, Baltimore, Maryland (United States); See, Alfred P.; Phallen, Jillian; Jackson, Christopher M.; Belcaid, Zineb; Ruzevick, Jacob [Department of Neurosurgery, Johns Hopkins Medical Institutes, Baltimore, Maryland (United States); Durham, Nicholas [Department of Immunology, Johns Hopkins Medical Institutes, Baltimore, Maryland (United States); Meyer, Christian [Department of Oncology, Johns Hopkins Medical Institutes, Baltimore, Maryland (United States); Harris, Timothy J. [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins Medical Institutes, Baltimore, Maryland (United States); Albesiano, Emilia; Pradilla, Gustavo [Department of Neurosurgery, Johns Hopkins Medical Institutes, Baltimore, Maryland (United States); Ford, Eric; Wong, John [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins Medical Institutes, Baltimore, Maryland (United States); Hammers, Hans-Joerg [Department of Immunology, Johns Hopkins Medical Institutes, Baltimore, Maryland (United States); Mathios, Dimitris; Tyler, Betty; Brem, Henry [Department of Neurosurgery, Johns Hopkins Medical Institutes, Baltimore, Maryland (United States); Tran, Phuoc T. [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins Medical Institutes, Baltimore, Maryland (United States); Pardoll, Drew; Drake, Charles G. [Department of Immunology, Johns Hopkins Medical Institutes, Baltimore, Maryland (United States); and others

2013-06-01

Purpose: Glioblastoma multiforme (GBM) is the most common primary brain tumor in adults, and radiation is one of the main treatment modalities. However, cure rates remain low despite best available therapies. Immunotherapy is a promising modality that could work synergistically with radiation, which has been shown to increase antigen presentation and promote a proinflammatory tumor microenvironment. Programmed-death-1 (PD-1) is a surface receptor expressed on activated and exhausted T cells, which mediate T cell inhibition upon binding with its ligand PD-L1, expressed on many tumor types including human GBMs. We tested the combination of anti-PD-1 immunotherapy with stereotactic radiosurgery in a mouse orthotopic GBM model. Methods and Materials: We performed intracranial implantation of mouse glioma cell line GL261 transfected with luciferase into C57BL/6 mice. Mice were stratified into 4 treatment groups: (1) control; (2) radiation only; (3) anti-PD-1 antibody only; and (4) radiation plus anti-PD-1 antibody. Overall survival was quantified. The mice were killed on day 21 after implantation to assess immunologic parameters in the brain/tumor, cervical lymph nodes, and spleen. Results: Improved survival was demonstrated with combination anti-PD-1 therapy plus radiation compared with either modality alone: median survival was 25 days in the control arm, 27 days in the anti-PD-1 antibody arm, 28 days in the radiation arm, and 53 days in the radiation plus anti-PD-1 therapy arm (P<.05 by log-rank Mantle-Cox). Long-term survival was seen only in the combined treatment arm, with a fraction (15%-40%) of animals alive at day 180+ after treatment. Immunologic data on day 21 after implantation showed increased tumor infiltration by cytotoxic T cells (CD8+/interferon-γ+/tumor necrosis factor-α+) and decreased regulatory T cells (CD4+/FOXP3) in the combined treatment group compared with the single modality arms. Conclusions: The combination of PD-1 blockade and localized

CD4~+Foxp3~+ regulatory T cells converted by rapamycin from peripheral CD4~+ CD25~-naive T cells display more potent regulatory ability in vitro

Institute of Scientific and Technical Information of China (English)

CHEN Jian-fei; GAO Jie; ZHANG Dong; WANG Zi-han; ZHU Ji-ye

2010-01-01

Background Rapamycin (RAPA) is a relatively new immunosuppressant drug that functions as a serine/threonine kinase inhibitor to prevent rejection in organ transplantation. RAPA blocks activation of T-effector (Teff) cells by inhibiting the response to interleukin-2. Recently, RAPA was also shown to selectively expand the T-regulator (Treg) cell population. To date, no studies have examined the mechanism by which RAPA converts Teff cells to Treg cells. Methods Peripheral CD4~+CD25~- naive T cells were cultivated with RAPA and B cells as antigen-presenting cells (APCs) in vitro. CD4~+CD25~- T cells were harvested after 6 days and analyzed for expression of forkhead box protein 3 (Foxp3) using flow cytometry. CD4~+CD25~+CD127~- subsets as the converted Tregs were isolated from the mixed lymphocyte reactions (MLR) with CD127 negative selection, followed by CD4 and CD25 positive selection using microbeads and magnetic separation column (MSC). Moreover, mRNA was extracted from converted Tregs and C57BL/6 naive CD4~+CD25~+ T cells and Foxp3 levels were examined by quantitative real-time polymerase chain reaction (rt-PCR). A total of 1×10~5 carboxyfluorescein succinimidyl ester (CFSE)-labeled naive CD4~+CD25~- T cells/well from C57BL/6 mice were cocultured with DBA/2 or C3H maturation of dendritic cells (mDCs) (0.25×10~5/well) in 96-well round-bottom plates for 6 days. Then 1×10~5 or 0.25×10~5 converted Treg cells were added to every well as regulatory cells. Cells were harvested after 6 days of culture and analyzed for proliferation of CFSE-labeled naive CD4~+CD25~- T cells using flow cytometry. Data were analyzed using CellQuest software.Results We found that RAPA can convert peripheral CD4~+CD25~- naive T Cells to CD4~+Foxp3~+ Treg cells using B cells as APCs, and this subtype of Treg can potently suppress Teff proliferation and maintain antigenic specificity. Conclusion Our findings provide evidence that RAPA induces Treg cell conversion from Teff cells and

[Increased expressions of peripheral PD-1+ lymphocytes and CD4+CD25+FOXP3+ T cells in gastric adenocarcinoma patients].

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Li, Hao; Li, Songyan; Hu, Shidong; Zou, Guijun; Hu, Zilong; Wei, Huahua; Wang, Yufeng; Du, Xiaohui

2017-01-01

Objective To detect the frequencies of peripheral programmed death-1 + (PD-1 + ) lymphocytes and CD4 + CD25 + FOXP3 + regulatory T cells in patients with gastric adenocarcinoma. Methods The study enrolled 29 patients with gastric adenocarcinoma and 29 age- and sex-matched healthy controls. Frequencies of PD-1 + lymphocytes and CD4 + CD25 + FOXP3 + regulatory T cells were detected using flow cytometry. Results The number of PD-1 + lymphocytes and CD4 + CD25 + FOXP3 + regulatory T cells in peripheral blood was higher in patients with gastric adenocarcinoma than that in the control group. Moreover, linear correlation analysis indicated a positive correlation between PD-1 expression and frequency of CD4 + CD25 + FOXP3 + regulatory T cells in peripheral blood of the patients. Conclusion Gastric adenocarcinoma patients present with increased PD-1 + lymphocytes and CD4 + CD25 + FOXP3 + regulatory T cells in the peripheral blood.

Anti-respiratory syncytial virus (RSV) G monoclonal antibodies reduce lung inflammation and viral lung titers when delivered therapeutically in a BALB/c mouse model.

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Caidi, Hayat; Miao, Congrong; Thornburg, Natalie J; Tripp, Ralph A; Anderson, Larry J; Haynes, Lia M

2018-06-01

RSV continues to be a high priority for vaccine and antiviral drug development. Unfortunately, no safe and effective RSV vaccine is available and treatment options are limited. Over the past decade, several studies have focused on the role of RSV G protein on viral entry, viral neutralization, and RSV-mediated pathology. Anti-G murine monoclonal antibody (mAb) 131-2G treatment has been previously shown to reduce weight loss, bronchoalveolar lavage (BAL) cell number, airway reactivity, and Th2-type cytokine production in RSV-infected mice more rapidly than a commercial humanized monoclonal antibody (mAb) against RSV F protein (Palivizumab). In this study, we have tested two human anti-RSV G mAbs, 2B11 and 3D3, by both prophylactic and therapeutic treatment for RSV in the BALB/c mouse model. Both anti-G mAbs reduced viral load, leukocyte infiltration and IFN-γ and IL-4 expression in cell-free BAL supernatants emphasizing the potential of anti-G mAbs as anti-inflammatory and antiviral strategies. Published by Elsevier B.V.

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

International Nuclear Information System (INIS)

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

1988-01-01

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

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

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

2015-01-01

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

Polyfunctional response by ImmTAC (IMCgp100) redirected CD8+ and CD4+ T cells.

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Boudousquie, Caroline; Bossi, Giovanna; Hurst, Jacob M; Rygiel, Karolina A; Jakobsen, Bent K; Hassan, Namir J

2017-11-01

The success of immune system-based cancer therapies depends on a broad immune response engaging a range of effector cells and mechanisms. Immune mobilizing monoclonal T cell receptors (TCRs) against cancer (ImmTAC™ molecules: fusion proteins consisting of a soluble, affinity enhanced TCR and an anti-CD3 scFv antibody) were previously shown to redirect CD8 + and CD4 + T cells against tumours. Here we present evidence that IMCgp100 (ImmTAC recognizing a peptide derived from the melanoma-specific protein, gp100, presented by HLA-A*0201) efficiently redirects and activates effector and memory cells from both CD8 + and CD4 + repertoires. Using isolated subpopulations of T cells, we find that both terminally differentiated and effector memory CD8 + T cells redirected by IMCgp100 are potent killers of melanoma cells. Furthermore, CD4 + effector memory T cells elicit potent cytotoxic activity leading to melanoma cell killing upon redirection by IMCgp100. The majority of T cell subsets belonging to both the CD8 + and CD4 + repertoires secrete key pro-inflammatory cytokines (tumour necrosis factor-α, interferon-γ, interleukin-6) and chemokines (macrophage inflammatory protein-1α-β, interferon-γ-inducible protein-10, monocyte chemoattractant protein-1). At an individual cell level, IMCgp100-redirected T cells display a polyfunctional phenotype, which is a hallmark of a potent anti-cancer response. This study demonstrates that IMCgp100 induces broad immune responses that extend beyond the induction of CD8 + T cell-mediated cytotoxicity. These findings are of particular importance because IMCgp100 is currently undergoing clinical trials as a single agent or in combination with check point inhibitors for patients with malignant melanoma. © 2017 The Authors. Immunology Published by John Wiley & Sons Ltd.

Cycling G1 CD34+/CD38+ cells potentiate the motility and engraftment of quiescent G0 CD34+/CD38-/low severe combined immunodeficiency repopulating cells.

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Byk, Tamara; Kahn, Joy; Kollet, Orit; Petit, Isabelle; Samira, Sarit; Shivtiel, Shoham; Ben-Hur, Herzl; Peled, Amnon; Piacibello, Wanda; Lapidot, Tsvee

2005-04-01

The mechanism of human stem cell expansion ex vivo is not fully understood. Furthermore, little is known about the mechanisms of human stem cell homing/repopulation and the role that differentiating progenitor cells may play in these processes. We report that 2- to 3-day in vitro cytokine stimulation of human cord blood CD34(+)-enriched cells induces the production of short-term repopulating, cycling G1 CD34(+)/CD38(+) cells with increased matrix metalloproteinase (MMP)-9 secretion as well as increased migration capacity to the chemokine stromal cell-derived factor-1 (SDF-1) and homing to the bone marrow of irradiated nonobese diabetic severe/combined immunodeficiency (NOD/SCID) mice. These cycling G1 cells enhance SDF-1-mediated in vitro migration and in vivo homing of quiescent G0 CD34(+) cells, which is partially abrogated after inhibition of MMP-2/-9 activity. Moreover, the engraftment potential of quiescent G0 SCID repopulating cells (SRCs) is also increased by the cycling G1 CD34(+)/CD38(+) cells. This effect is significantly abrogated after incubation of cycling G1 cells with a neutralizing anti-CXCR4 antibody. Our data suggest synergistic interactions between accessory cycling G1 CD34(+)/CD38(+) committed progenitor cells and quiescent, primitive G0 CD34(+)/CD38(-/low) SRC/stem cells, the former increasing the motility and engraftment potential of the latter, partly via secretion of MMP-9.

Immunohistochemical, lectin histochemical and ultrastructural studies of canine transmissible venereal tumor in Brazil

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Mariana B. Mascarenhas