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Nayak TR, Wang H, Pant A, Zheng M, Junginger H, Goh WJ, Lee CK, Zou S, Alonso S, Czarny B, Storm G, Sow CH, Lee C, Pastorin G. ZnO Nano-Rod Devices for Intradermal Delivery and Immunization. Nanomaterials (Basel) 2017; 7:nano7060147. [PMID: 28617335 PMCID: PMC5485794 DOI: 10.3390/nano7060147] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 06/09/2017] [Accepted: 06/09/2017] [Indexed: 11/23/2022]
Abstract
Intradermal delivery of antigens for vaccination is a very attractive approach since the skin provides a rich network of antigen presenting cells, which aid in stimulating an immune response. Numerous intradermal techniques have been developed to enhance penetration across the skin. However, these methods are invasive and/or affect the skin integrity. Hence, our group has devised zinc oxide (ZnO) nano-rods for non-destructive drug delivery. Chemical vapour deposition was used to fabricate aligned nano-rods on ZnO pre-coated silicon chips. The nano-rods’ length and diameter were found to depend on the temperature, time, quality of sputtered silicon chips, etc. Vertically aligned ZnO nano-rods with lengths of 30–35 µm and diameters of 200–300 nm were selected for in vitro human skin permeation studies using Franz cells with Albumin-fluorescein isothiocyanate (FITC) absorbed on the nano-rods. Fluorescence and confocal studies on the skin samples showed FITC penetration through the skin along the channels formed by the nano-rods. Bradford protein assay on the collected fluid samples indicated a significant quantity of Albumin-FITC in the first 12 h. Low antibody titres were observed with immunisation on Balb/c mice with ovalbumin (OVA) antigen coated on the nano-rod chips. Nonetheless, due to the reduced dimensions of the nano-rods, our device offers the additional advantage of excluding the simultaneous entrance of microbial pathogens. Taken together, these results showed that ZnO nano-rods hold the potential for a safe, non-invasive, and painless intradermal drug delivery.
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Affiliation(s)
- Tapas R Nayak
- Department of Pharmacy, National University of Singapore, Singapore 117583, Singapore.
| | - Hao Wang
- Department of Electrical Engineering, National University of Singapore, Singapore 117583, Singapore.
| | - Aakansha Pant
- Department of Pharmacy, National University of Singapore, Singapore 117583, Singapore.
| | - Minrui Zheng
- Department of Physics, National University of Singapore, Singapore 117551, Singapore.
| | - Hans Junginger
- Department of Pharmacy, National University of Singapore, Singapore 117583, Singapore.
| | - Wei Jiang Goh
- Department of Pharmacy, National University of Singapore, Singapore 117583, Singapore.
- NUS Graduate School for Integrative Sciences and Engineering, Centre for Life Sciences (CeLS), Singapore 117456, Singapore.
| | - Choon Keong Lee
- Department of Pharmacy, National University of Singapore, Singapore 117583, Singapore.
| | - Shui Zou
- Department of Pharmacy, National University of Singapore, Singapore 117583, Singapore.
| | - Sylvie Alonso
- Department of Microbiology, National University of Singapore, Singapore 117545, Singapore.
| | - Bertrand Czarny
- School of Materials Science and Engineering (MSE) & Lee Kong Chian School of medicine (LKCmedicine), Nanyang Technological University, Singapore 636921, Singapore.
| | - Gert Storm
- Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands.
| | - Chorng Haur Sow
- Department of Physics, National University of Singapore, Singapore 117551, Singapore.
| | - Chengkuo Lee
- Department of Electrical Engineering, National University of Singapore, Singapore 117583, Singapore.
| | - Giorgia Pastorin
- Department of Pharmacy, National University of Singapore, Singapore 117583, Singapore.
- Department of Physics, National University of Singapore, Singapore 117551, Singapore.
- NUSNNI-NanoCore, National University of Singapore, T-Lab, Blk E3-05-29, 2 Engineering Drive 3, Singapore 117581, Singapore.
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Nayak TR, Andreou C, Oseledchyk A, Marcus WD, Wong HC, Massagué J, Kircher MF. Tissue factor-specific ultra-bright SERRS nanostars for Raman detection of pulmonary micrometastases. Nanoscale 2017; 9:1110-1119. [PMID: 27991632 PMCID: PMC5438878 DOI: 10.1039/c6nr08217c] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Here we demonstrate a novel application of 'surface enhanced resonance Raman scattering nanoparticles' (SERRS NPs) for imaging breast cancer lung metastases with much higher precision than currently feasible. A breast cancer lung metastasis mouse model was established by intravenous injection of LM2 cells. These mice were intravenously administered SERRS NPs conjugated with ALT-836, an anti-tissue factor (TF) monoclonal antibody, and subjected to Raman imaging to visualize the expression of TF both in vivo and ex vivo. Raman imaging indicated marked uptake of αTF-SERRS-NPs by the lung metastases compared to isotype and blocking controls. Conversely, little uptake of αTF-SERRS-NPs was observed in the lungs of healthy mice. Successful detection and delineation of pulmonary micrometastatic lesions as small as 200 μm, corroborated by histology, immunohistochemistry, and bioluminescence imaging confirmed the suitability of both TF as a target and αTF-SERRS-NPs as an effective contrast agent for imaging breast cancer lung metastases. Further advancements of this technique in the form of Raman endoscopes coupled with ultrabright SERRS NPs developed in this work could lead to minimally invasive detection and resection of lung metastases.
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Affiliation(s)
- Tapas R Nayak
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.
| | - Chrysafis Andreou
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.
| | - Anton Oseledchyk
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.
| | | | - Hing C Wong
- Altor BioScience Corporation, Miramar, FL 33025, USA
| | - Joan Massagué
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Moritz F Kircher
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA. and Center for Molecular Imaging and Nanotechnology (CMINT), Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA and Department of Radiology, Weill Cornell Medical College, New York, New York 10065, USA
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Shi S, Orbay H, Yang Y, Graves SA, Nayak TR, Hong H, Hernandez R, Luo H, Goel S, Theuer CP, Nickles RJ, Cai W. PET Imaging of Abdominal Aortic Aneurysm with 64Cu-Labeled Anti-CD105 Antibody Fab Fragment. J Nucl Med 2015; 56:927-32. [PMID: 25883125 DOI: 10.2967/jnumed.114.153098] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Accepted: 03/31/2015] [Indexed: 01/11/2023] Open
Abstract
UNLABELLED The critical challenge in abdominal aortic aneurysm (AAA) research is the accurate diagnosis and assessment of AAA progression. Angiogenesis is a pathologic hallmark of AAA, and CD105 is highly expressed on newly formed vessels. Our goal was to use (64)Cu-labeled anti-CD105 antibody Fab fragment for noninvasive assessment of angiogenesis in the aortic wall in a murine model of AAA. METHODS Fab fragment of TRC105, a mAb that specifically binds to CD105, was generated by enzymatic papain digestion and conjugated to NOTA (1,4,7-triazacyclononane-1,4,7-triacetic acid) for (64)Cu labeling. The binding affinity/specificity of NOTA-TRC105-Fab was evaluated by flow cytometry and various ex vivo studies. BALB/c mice were anesthetized and treated with calcium phosphate to induce AAA and underwent weekly PET scans using (64)Cu-NOTA-TRC105-Fab. Biodistribution and autoradiography studies were also performed to confirm the accuracy of PET results. RESULTS NOTA-TRC105-Fab exhibited high purity and specifically bound to CD105 in vitro. Uptake of (64)Cu-NOTA-TRC105-Fab increased from a control level of 3.4 ± 0.1 to 9.5 ± 0.4 percentage injected dose per gram (%ID/g) at 6 h after injection on day 5 and decreased to 7.2 ± 1.4 %ID/g on day 12, which correlated well with biodistribution and autoradiography studies (i.e., much higher tracer uptake in AAA than normal aorta). Of note, enhanced AAA contrast was achieved, due to the minimal background in the abdominal area of mice. Degradation of elastic fibers and highly expressed CD105 were observed in ex vivo studies. CONCLUSION (64)Cu-NOTA-TRC105-Fab cleared rapidly through the kidneys, which enabled noninvasive PET imaging of the aorta with enhanced contrast and showed increased angiogenesis (CD105 expression) during AAA. (64)Cu-NOTA-TRC105-Fab PET may potentially be used for future diagnosis and prognosis of AAA.
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Affiliation(s)
- Sixiang Shi
- Materials Science Program, University of Wisconsin-Madison, Madison, Wisconsin
| | - Hakan Orbay
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Yunan Yang
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Stephen A Graves
- Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin
| | - Tapas R Nayak
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Hao Hong
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Reinier Hernandez
- Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin
| | - Haiming Luo
- Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin
| | - Shreya Goel
- Materials Science Program, University of Wisconsin-Madison, Madison, Wisconsin
| | | | - Robert J Nickles
- Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin
| | - Weibo Cai
- Materials Science Program, University of Wisconsin-Madison, Madison, Wisconsin Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin University of Wisconsin Carbone Cancer Center, Madison, Wisconsin
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Hong H, Nayak TR, Shi S, Graves SA, Fliss BC, Barnhart TE, Cai W. Generation and screening of monoclonal antibodies for immunoPET imaging of IGF1R in prostate cancer. Mol Pharm 2014; 11:3624-30. [PMID: 25157758 PMCID: PMC4186682 DOI: 10.1021/mp5003637] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Insulin-like growth factor 1 receptor (IGF1R) plays an important role in proliferation, apoptosis, angiogenesis, and tumor invasion. The expression level of IGF1R is related to resistance to several targeted therapies. The goal of this study was to develop an immunoPET tracer for imaging of IGF1R in prostate cancer. Murine antibodies against human IGF1R were generated in BALB/c mice, which were screened in IGF1R-positive MCF-7 cells using flow cytometry as well as biodistribution studies with multiple (64)Cu-labeled antibody clones. The antibody production method we adopted could readily produce milligram quantities of anti-IGF1R antibodies for in vivo studies. One antibody clone (1A2G11) with the highest affinity for IGF1R was selected and conjugated to NOTA for (64)Cu-labeling. NOTA-1A2G11 maintained IGF1R specificity/avidity based on flow cytometry. (64)Cu-labeling was achieved with good yield (>50%) and high specific activity (>1 Ci/μmol). Serial PET imaging revealed that uptake of (64)Cu-NOTA-1A2G11 was 2.8 ± 0.7, 10.2 ± 2.6, and 9.6 ± 1.7 %ID/g in IGF1R-positive DU-145 tumors at 4, 24, and 48 h postinjection, respectively (n = 3), significantly higher than that in IGF1R-negative LNCaP tumors (<3 %ID/g at each time point) except at 4 h postinjection. Histology studies showed strong correlations between IGF1R expression level in the prostate cancer tumor tissues and tumor uptake of (64)Cu-NOTA-1A2G11. Prominent, persistent, and IGF1R-specific uptake of (64)Cu-NOTA-1A2G11 in IGF1R-positive prostate tumors holds strong potential for future cancer diagnosis, prognosis, and therapy using this antibody.
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Affiliation(s)
- Hao Hong
- Department of Radiology, ‡Materials Science Program, §Department of Medical Physics, and ∥Department of Biochemistry, University of Wisconsin-Madison , Madison, Wisconsin 53705-2275, United States
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Nayak TR, Hong H, Zhang Y, Cai W. Multimodality imaging of CXCR4 in cancer: current status towards clinical translation. Curr Mol Med 2014; 13:1538-48. [PMID: 24206137 DOI: 10.2174/1566524013666131111121325] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2012] [Revised: 04/02/2012] [Accepted: 09/10/2013] [Indexed: 12/17/2022]
Abstract
CXCR4 has gained tremendous attention over the last decade, since it was found to be up-regulated in a wide variety of cancer types, in addition to its role in human immunodeficiency virus infection. Molecular imaging of CXCR4 with small molecules, peptides, and antibodies has been a vibrant research area over the last several years. In this review article, we will summarize the current status of imaging CXCR4 with fluorescence, bioluminescence, positron emission tomography, and single-photon emission computed tomography techniques. Since each molecular imaging modality has its own strengths and weaknesses, dualmodality probes that can be detected by more than one imaging techniques have also been investigated. Noninvasive visualization of CXCR4 expression has potential clinical applications in multiple facets of patient management. While big strides have been made over the last several years in the development of CXCR4- targeted imaging probes, clinical translation and investigation of these agents in cancer patients are eagerly awaited. Since CXCR4 is also involved in many other diseases beyond cancer, these clinically translatable probes can also play multiple roles in other pathological disorders such as myocardial infarction and several immunodeficiency disorders.
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Affiliation(s)
- T R Nayak
- Departments of Radiology and Medical Physics, University of Wisconsin - Madison, Room 7137, 1111 Highland Avenue, Madison, WI 53705-2275, USA.
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Chen F, Nayak TR, Goel S, Valdovinos HF, Hong H, Theuer CP, Barnhart TE, Cai W. In vivo tumor vasculature targeted PET/NIRF imaging with TRC105(Fab)-conjugated, dual-labeled mesoporous silica nanoparticles. Mol Pharm 2014; 11:4007-14. [PMID: 24937108 PMCID: PMC4218929 DOI: 10.1021/mp500306k] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
![]()
Multifunctional
mesoporous silica nanoparticles (MSN) with well-integrated
multimodality imaging properties have generated increasing research
interest in the past decade. However, limited progress has been made
in developing MSN-based multimodality imaging agents to image tumors.
We describe the successful conjugation of, copper-64 (64Cu, t1/2 = 12.7 h), 800CW (a near-infrared
fluorescence [NIRF] dye), and TRC105 (a human/murine chimeric IgG1
monoclonal antibody) to the surface of MSN via well-developed surface
engineering procedures, resulting in a dual-labeled MSN for in vivo
targeted positron emission tomography (PET) imaging/NIRF imaging of
the tumor vasculature. Pharmacokinetics and tumor targeting efficacy/specificity
in 4T1 murine breast tumor-bearing mice were thoroughly investigated
through various in vitro, in vivo, and ex vivo experiments. Dual-labeled
MSN is an attractive candidate for future cancer theranostics.
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Affiliation(s)
- Feng Chen
- Department of Radiology, University of Wisconsin-Madison , Madison, Wisconsin 53792, United States
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Nayak TR, Krasteva LK, Cai W. Multimodality imaging of RNA interference. Curr Med Chem 2014; 20:3664-75. [PMID: 23745567 DOI: 10.2174/0929867311320290012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Revised: 03/13/2013] [Accepted: 03/13/2013] [Indexed: 12/16/2022]
Abstract
The discovery of small interfering RNAs (siRNAs) and their potential to knock down virtually any gene of interest has ushered in a new era of RNA interference (RNAi). Clinical use of RNAi faces severe limitations due to inefficiency delivery of siRNA or short hairpin RNA (shRNA). Many molecular imaging techniques have been adopted in RNAi-related research for evaluation of siRNA/shRNA delivery, biodistribution, pharmacokinetics, and the therapeutic effect. In this review article, we summarize the current status of in vivo imaging of RNAi. The molecular imaging techniques that have been employed include bioluminescence/fluorescence imaging, magnetic resonance imaging/ spectroscopy, positron emission tomography, single-photon emission computed tomography, and various combinations of these techniques. Further development of non-invasive imaging strategies for RNAi, not only focusing on the delivery of siRNA/shRNA but also the therapeutic efficacy, is critical for future clinical translation. Rigorous validation will be needed to confirm that biodistribution of the carrier is correlated with that of siRNA/shRNA, since imaging only detects the label (e.g. radioisotopes) but not the gene or carrier themselves. It is also essential to develop multimodality imaging approaches for realizing the full potential of therapeutic RNAi, as no single imaging modality may be sufficient to simultaneously monitor both the gene delivery and silencing effect of RNAi.
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Affiliation(s)
- T R Nayak
- Department of Radiology, University of Wisconsin - Madison, Madison, WI 53705-2275, USA
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Li J, Pant A, Chin CF, Ang WH, Ménard-Moyon C, Nayak TR, Gibson D, Ramaprabhu S, Panczyk T, Bianco A, Pastorin G. In vivo biodistribution of platinum-based drugs encapsulated into multi-walled carbon nanotubes. Nanomedicine 2014; 10:1465-75. [PMID: 24486857 DOI: 10.1016/j.nano.2014.01.004] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Revised: 01/08/2014] [Accepted: 01/17/2014] [Indexed: 02/04/2023]
Abstract
Carbon nanotubes (CNTs) are promising drug delivery systems due to their external functionalizable surface and their hollowed cavity that can encapsulate several bioactive molecules. In this study, the chemotherapeutic drug cisplatin or an inert platinum(IV) complex were entrapped inside functionalized-multi-walled-CNTs and intravenously injected into mice to investigate the influence of CNTs on the biodistribution of Pt-based molecules. The platinum levels in vital organs suggested that functionalized-CNTs did not affect cisplatin distribution, while they significantly enhanced the accumulation of Pt(IV) sample in some tissues (e.g. in the lungs, suggesting their potential application in lung cancer therapy) and reduced both kidney and liver accumulation (thus decreasing eventual nephrotoxicity, a typical side effect of cisplatin). Concurrently, CNTs did not induce any intrinsic abnormal immune response or inflammation, as confirmed by normal cytokine levels and histological evaluations. Therefore, functionalized nanotubes represent an efficient nano-carrier to improve accumulation of Pt species in targeted tissues/organs. From the clinical editor: In this preclinical study functionalized carbon nanotubes are reported to be safe and efficient for targeted delivery of platinum-containing compounds in rodents. Approaches like this may improve the treatment of specific cancers, since platinum based chemotherapies are commonly used, yet limited by toxicity and relatively poor target tissue concentration.
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Affiliation(s)
- Jian Li
- Department of Pharmacy, National University of Singapore, Science Drive 2, Singapore
| | - Aakansha Pant
- Department of Pharmacy, National University of Singapore, Science Drive 2, Singapore
| | - Chee Fei Chin
- Department of Chemistry, National University of Singapore, Singapore
| | - Wee Han Ang
- Department of Chemistry, National University of Singapore, Singapore.
| | - Cécilia Ménard-Moyon
- CNRS, Institut de Biologie Moléculaire et Cellulaire, Laboratoire d'Immunopathologie et Chimie Thérapeutique, Strasbourg, France
| | - Tapas R Nayak
- Department of Pharmacy, National University of Singapore, Science Drive 2, Singapore
| | - Dan Gibson
- School of Pharmacy, The Hebrew University of Jerusalem, Israel
| | - Sundara Ramaprabhu
- Department of Physics, Indian Institute of Technology Madras, Chennai 600 036, India
| | - Tomasz Panczyk
- Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences ul. Niezapominajek 8, 30239 Cracow, Poland
| | - Alberto Bianco
- CNRS, Institut de Biologie Moléculaire et Cellulaire, Laboratoire d'Immunopathologie et Chimie Thérapeutique, Strasbourg, France.
| | - Giorgia Pastorin
- Department of Pharmacy, National University of Singapore, Science Drive 2, Singapore; NUS Graduate School for Integrative Sciences and Engineering, Centre for Life Sciences (CeLS), 28 Medical Drive, Singapore; NUSNNI-NanoCore, National University of Singapore, T-Lab Level 11, 5A Engineering Drive 1, Singapore.
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Zhang Y, Hong H, Nayak TR, Valdovinos HF, Myklejord DV, Theuer CP, Barnhart TE, Cai W. Erratum to: Imaging tumor angiogenesis in breast cancer experimental lung metastasis with positron emission tomography, near-infrared fluorescence, and bioluminescence. Angiogenesis 2013. [DOI: 10.1007/s10456-013-9351-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Shi S, Yang K, Hong H, Valdovinos HF, Nayak TR, Zhang Y, Theuer CP, Barnhart TE, Liu Z, Cai W. Tumor vasculature targeting and imaging in living mice with reduced graphene oxide. Biomaterials 2013; 34:3002-9. [PMID: 23374706 DOI: 10.1016/j.biomaterials.2013.01.047] [Citation(s) in RCA: 126] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2012] [Accepted: 01/07/2013] [Indexed: 01/16/2023]
Abstract
Graphene-based nanomaterials have attracted tremendous attention in the field of biomedicine due to their intriguing properties. Herein, we report tumor vasculature targeting and imaging in living mice using reduced graphene oxide (RGO), which was conjugated to the anti-CD105 antibody TRC105. The RGO conjugate, (64)Cu-NOTA-RGO-TRC105, exhibited excellent stability in vitro and in vivo. Serial positron emission tomography (PET) imaging studies non-invasively assessed the pharmacokinetics and demonstrated specific targeting of (64)Cu-NOTA-RGO-TRC105 to 4T1 murine breast tumors in vivo, compared to non-targeted RGO conjugate ((64)Cu-NOTA-RGO). In vivo (e.g., blocking 4T1 tumor uptake with excess TRC105), in vitro (e.g., flow cytometry), and ex vivo (e.g., histology) experiments confirmed the specificity of (64)Cu-NOTA-RGO-TRC105 for tumor vascular CD105. Since RGO exhibits desirable properties for photothermal therapy, the tumor-specific RGO conjugate developed in this work may serve as a promising theranostic agent that integrates imaging and therapeutic components.
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Affiliation(s)
- Sixiang Shi
- Materials Science Program, University of Wisconsin-Madison, Madison, WI 53705-2275, USA
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Zhang Y, Hong H, Orbay H, Valdovinos HF, Nayak TR, Theuer CP, Barnhart TE, Cai W. PET imaging of CD105/endoglin expression with a ⁶¹/⁶⁴Cu-labeled Fab antibody fragment. Eur J Nucl Med Mol Imaging 2013; 40:759-67. [PMID: 23344138 DOI: 10.1007/s00259-012-2334-2] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Accepted: 12/25/2012] [Indexed: 10/27/2022]
Abstract
PURPOSE The goal of this study was to generate and characterize the Fab fragment of TRC105, a monoclonal antibody that binds with high affinity to human and murine CD105 (i.e., endoglin), and investigate its potential for PET imaging of tumor angiogenesis in a small-animal model after (61/64)Cu labeling. METHODS TRC105-Fab was generated by enzymatic papain digestion. The integrity and CD105 binding affinity of TRC105-Fab was evaluated before NOTA (1,4,7-triazacyclononane-1,4,7-triacetic acid) conjugation and (61/64)Cu labeling. Serial PET imaging and biodistribution studies were carried out in the syngeneic 4T1 murine breast cancer model to quantify tumor targeting efficiency and normal organ distribution of (61/64)Cu-NOTA-TRC105-Fab. Blocking studies with unlabeled TRC105 were performed to confirm CD105 specificity of the tracer in vivo. Immunofluorescence staining was also conducted to correlate tracer uptake in the tumor and normal tissues with CD105 expression. RESULTS TRC105-Fab was produced with high purity through papain digestion of TRC105, as confirmed by SDS-PAGE, HPLC analysis, and mass spectrometry. (61/64)Cu labeling of NOTA-TRC105-Fab was achieved with about 50 % yield (specific activity about 44 GBq/μmol). PET imaging revealed rapid uptake of (64)Cu-NOTA-TRC105-Fab in the 4T1 tumor (3.6 ± 0.4, 4.2 ± 0.5, 4.9 ± 0.3, 4.4 ± 0.7, and 4.6 ± 0.8 %ID/g at 0.5, 2, 5, 16, and 24 h after injection, respectively; n = 4). Since tumor uptake peaked soon after tracer injection, (61)Cu-labeled TRC105-Fab was also able to provide tumor contrast at 3 and 8 h after injection. CD105 specificity of the tracer was confirmed with blocking studies and histological examination. CONCLUSION We report PET imaging of CD105 expression using (61/64)Cu-NOTA-TRC105-Fab, which exhibited prominent and target-specific uptake in the 4T1 tumor. The use of a Fab fragment led to much faster tumor uptake (which peaked at a few hours after tracer injection) compared to radiolabeled intact antibody, which may be translated into same-day immunoPET imaging for clinical investigation.
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Affiliation(s)
- Yin Zhang
- Department of Medical Physics, University of Wisconsin - Madison, 1111 Highland Avenue, Madison, WI 53705-2275, USA
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Hong H, Zhang Y, Orbay H, Valdovinos HF, Nayak TR, Bean J, Theuer CP, Barnhart TE, Cai W. Positron emission tomography imaging of tumor angiogenesis with a (61/64)Cu-labeled F(ab')(2) antibody fragment. Mol Pharm 2013; 10:709-16. [PMID: 23316869 DOI: 10.1021/mp300507r] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The objective of this study was to characterize the in vitro and in vivo properties of the F(ab')(2) fragment of TRC105, a human/murine chimeric IgG1 monoclonal antibody that binds with high avidity to human and murine CD105 (i.e., endoglin), and investigate its potential for positron emission tomography (PET) imaging of tumor angiogenesis after (61/64)Cu-labeling. TRC105-F(ab')(2) of high purity was produced by pepsin digestion of TRC105, which was confirmed by SDS-PAGE, HPLC analysis, and mass spectrometry. (61/64)Cu-labeling of NOTA-TRC105-F(ab')(2) (NOTA denotes 1,4,7-triazacyclononane-1,4,7-triacetic acid) was achieved with yields of >75% (specific activity: ∼115 GBq/μmol). PET imaging revealed rapid tumor uptake of (64)Cu-NOTA-TRC105-F(ab')(2) in the 4T1 murine breast cancer model (5.8 ± 0.8, 7.6 ± 0.6, 5.6 ± 0.4, 5.0 ± 0.6, and 3.8 ± 0.7% ID/g at 0.5, 3, 16, 24, and 48 h postinjection respectively; n = 4). Since tumor uptake peaked at 3 h postinjection, (61)Cu-NOTA-TRC105-F(ab')(2) also gave good tumor contrast at 3 and 8 h postinjection. CD105 specificity of the tracers was confirmed by blocking studies and histopathology. In conclusion, the use of a F(ab')(2) fragment led to more rapid tumor uptake (which peaked at 3 h postinjection) than radiolabeled intact antibody (which often peaked after 24 h postinjection), which may allow for same day immunoPET imaging in future clinical studies.
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Affiliation(s)
- Hao Hong
- Department of Radiology, University of Wisconsin-Madison, Madison, WI 53705-2275, United States
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Zhang Y, Hong H, Niu G, Valdovinos HF, Orbay H, Nayak TR, Chen X, Barnhart TE, Cai W. Positron emission tomography imaging of vascular endothelial growth factor receptor expression with (61)Cu-labeled lysine-tagged VEGF121. Mol Pharm 2012; 9:3586-94. [PMID: 23137334 DOI: 10.1021/mp3005269] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Overexpression of vascular endothelial growth factor (VEGF) and VEGF receptors (VEGFRs) indicates poor prognosis for cancer patients in a variety of clinical studies. Our goal is to develop a tracer for positron emission tomography (PET) imaging of VEGFR expression using recombinant human VEGF121 with three lysine residues fused to the N-terminus (denoted as K3-VEGF121), which can facilitate radiolabeling without affecting its VEGFR binding affinity. K3-VEGF121 was conjugated with 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA) and labeled with (61)Cu (t1/2: 3.3 h; 62% β(+)). The IC50 value of NOTA-K3-VEGF121 for VEGFR-2 was comparable to that of K3-VEGF121 (1.50 and 0.65 nM, respectively) based on a cell binding assay. (61)Cu labeling was achieved with good yield (55 ± 10%) and specific activity (4.2 GBq/mg). Serial PET imaging showed that the 4T1 tumor uptake of (61)Cu-NOTA-K3-VEGF121 was 3.4 ± 0.5, 4.9 ± 1.0, 5.2 ± 1.0, and 4.8 ± 0.8%ID/g (n = 4) at 0.5, 2, 4, and 8 h postinjection, respectively, which was consistent with biodistribution data measured by γ counting. Blocking experiments and ex vivo histology confirmed the VEGFR specificity of (61)Cu-NOTA-K3-VEGF121. Extrapolated human dosimetry calculation showed that liver was the organ with the highest radiation dose. The use of (61)Cu as the radiolabel is desirable for small proteins such as K3-VEGF121, which has a much higher β(+) branching ratio than the commonly used (64)Cu (62% vs 17%), thereby offering stronger signal intensity and lower tracer dose for PET imaging.
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Affiliation(s)
- Yin Zhang
- Department of Medical Physics, University of Wisconsin-Madison , Wisconsin, United States
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14
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Abstract
UNLABELLED Upregulation of tissue factor (TF) expression leads to increased patient morbidity and mortality in many solid tumor types. The goal of this study was to develop a PET tracer for imaging of TF expression in pancreatic cancer. METHODS ALT-836, a chimeric antihuman TF monoclonal antibody, was conjugated to 2-S-(4-isothiocyanatobenzyl)-1,4,7-triazacyclononane-1,4,7-triacetic acid (p-SCN-Bn-NOTA) and labeled with (64)Cu. To compare the TF binding affinity of ALT-836 and NOTA-ALT-836, flow cytometry analysis was performed in 3 pancreatic cancer cell lines with different expression levels of TF (from low to high: PANC-1, ASPC-1, and BXPC-3). PET, biodistribution, blocking, and histology studies were performed on pancreatic tumor-bearing mice to evaluate the ability and specificity of (64)Cu-NOTA-ALT-836 to target TF in vivo. RESULTS There was no difference in TF binding affinity between ALT-836 and NOTA-ALT-836. (64)Cu-labeling was achieved with high yield and specific activity. Serial PET revealed that the uptake of (64)Cu-NOTA-ALT-836 in BXPC-3 tumors (high TF expression) was 5.7 ± 1.8, 10.4 ± 0.8, and 16.5 ± 2.6 percentage injected dose per gram at 4, 24, and 48 h after injection, respectively (n = 4), significantly higher than that in the PANC-1 and ASPC-1 tumors. Biodistribution data as measured by γ-counting were consistent with the PET findings. Blocking experiments and histology further confirmed the TF specificity of (64)Cu-NOTA-ALT-836. CONCLUSION Herein we report the first successful PET imaging of TF expression. Persistent and TF-specific uptake of (64)Cu-NOTA-ALT-836 was observed in pancreatic cancer models.
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Affiliation(s)
- Hao Hong
- Department of Radiology, University of Wisconsin, Madison, WI, USA
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Abstract
Graphene, with its excellent physical, chemical, and mechanical properties, holds tremendous potential for a wide variety of biomedical applications. As research on graphene-based nanomaterials is still at a nascent stage due to the short time span since its initial report in 2004, a focused review on this topic is timely and necessary. In this feature review, we first summarize the results from toxicity studies of graphene and its derivatives. Although literature reports have mixed findings, we emphasize that the key question is not how toxic graphene itself is, but how to modify and functionalize it and its derivatives so that they do not exhibit acute/chronic toxicity, can be cleared from the body over time, and thereby can be best used for biomedical applications. We then discuss in detail the exploration of graphene-based nanomaterials for tissue engineering, molecular imaging, and drug/gene delivery applications. The future of graphene-based nanomaterials in biomedicine looks brighter than ever, and it is expected that they will find a wide range of biomedical applications with future research effort and interdisciplinary collaboration.
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Affiliation(s)
- Yin Zhang
- Department of Medical Physics, University of Wisconsin - Madison, WI , USA
| | - Tapas R. Nayak
- Department of Radiology, University of Wisconsin - Madison, WI, USA
| | - Hao Hong
- Department of Radiology, University of Wisconsin - Madison, WI, USA
| | - Weibo Cai
- Department of Medical Physics, University of Wisconsin - Madison, WI , USA
- Department of Radiology, University of Wisconsin - Madison, WI, USA
- University of Wisconsin Carbone Cancer Center, Madison, WI, USA
- Requests for reprints: Weibo Cai, PhD, Departments of Radiology and Medical Physics, School of Medicine and Public Health, University of Wisconsin - Madison, 1111 Highland Ave, Room 7137, Madison, WI 53705-2275, USA. Fax: 1-608-265-0614; Tel: 1-608-262-1749;
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Hong H, Yang K, Zhang Y, Engle JW, Feng L, Yang Y, Nayak TR, Goel S, Bean J, Theuer CP, Barnhart TE, Liu Z, Cai W. In vivo targeting and imaging of tumor vasculature with radiolabeled, antibody-conjugated nanographene. ACS Nano 2012; 6:2361-70. [PMID: 22339280 PMCID: PMC3314116 DOI: 10.1021/nn204625e] [Citation(s) in RCA: 159] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Herein we demonstrate that nanographene can be specifically directed to the tumor neovasculature in vivo through targeting of CD105 (i.e., endoglin), a vascular marker for tumor angiogenesis. The covalently functionalized nanographene oxide (GO) exhibited excellent stability and target specificity. Pharmacokinetics and tumor targeting efficacy of the GO conjugates were investigated with serial noninvasive positron emission tomography imaging and biodistribution studies, which were validated by in vitro, in vivo, and ex vivo experiments. The incorporation of an active targeting ligand (TRC105, a monoclonal antibody that binds to CD105) led to significantly improved tumor uptake of functionalized GO, which was specific for the neovasculature with little extravasation, warranting future investigation of these GO conjugates for cancer-targeted drug delivery and/or photothermal therapy to enhance therapeutic efficacy. Since poor extravasation is a major hurdle for nanomaterial-based tumor targeting in vivo, this study also establishes CD105 as a promising vascular target for future cancer nanomedicine.
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MESH Headings
- Animals
- Antibodies, Monoclonal/chemistry
- Antibodies, Monoclonal/immunology
- Antigens, CD/immunology
- Cell Line, Tumor
- Copper Radioisotopes
- Endoglin
- Graphite/chemistry
- Heterocyclic Compounds/chemistry
- Heterocyclic Compounds, 1-Ring
- Human Umbilical Vein Endothelial Cells/metabolism
- Humans
- Immunoconjugates/chemistry
- Immunoconjugates/metabolism
- Immunoconjugates/pharmacokinetics
- Isotope Labeling
- Mammary Neoplasms, Experimental/blood supply
- Mammary Neoplasms, Experimental/diagnosis
- Mammary Neoplasms, Experimental/metabolism
- Mammary Neoplasms, Experimental/therapy
- Mice
- Molecular Imaging/methods
- Nanoconjugates/chemistry
- Neovascularization, Pathologic/diagnostic imaging
- Neovascularization, Pathologic/metabolism
- Oxides/chemistry
- Positron-Emission Tomography
- Receptors, Cell Surface/immunology
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Affiliation(s)
- Hao Hong
- Department of Radiology, University of Wisconsin - Madison, Madison, WI, USA
| | - Kai Yang
- Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Institute of Functional Nano and Soft Materials Laboratory (FUNSOM), Soochow University, Suzhou, Jiangsu, China
| | - Yin Zhang
- Department of Medical Physics, University of Wisconsin - Madison, Madison, WI, USA
| | - Jonathan W. Engle
- Department of Medical Physics, University of Wisconsin - Madison, Madison, WI, USA
| | - Liangzhu Feng
- Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Institute of Functional Nano and Soft Materials Laboratory (FUNSOM), Soochow University, Suzhou, Jiangsu, China
| | - Yunan Yang
- Department of Radiology, University of Wisconsin - Madison, Madison, WI, USA
| | - Tapas R. Nayak
- Department of Radiology, University of Wisconsin - Madison, Madison, WI, USA
| | - Shreya Goel
- Centre of Nanotechnology, Indian Institute of Technology, Roorkee, India
| | - Jero Bean
- Department of Radiology, University of Wisconsin - Madison, Madison, WI, USA
| | | | - Todd E. Barnhart
- Department of Medical Physics, University of Wisconsin - Madison, Madison, WI, USA
| | - Zhuang Liu
- Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Institute of Functional Nano and Soft Materials Laboratory (FUNSOM), Soochow University, Suzhou, Jiangsu, China
- Corresponding Author: OR
| | - Weibo Cai
- Department of Radiology, University of Wisconsin - Madison, Madison, WI, USA
- Department of Medical Physics, University of Wisconsin - Madison, Madison, WI, USA
- University of Wisconsin Carbone Cancer Center, Madison, WI, USA
- Corresponding Author: OR
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Hong H, Zhang Y, Engle JW, Nayak TR, Theuer CP, Nickles RJ, Barnhart TE, Cai W. In vivo targeting and positron emission tomography imaging of tumor vasculature with (66)Ga-labeled nano-graphene. Biomaterials 2012; 33:4147-56. [PMID: 22386918 DOI: 10.1016/j.biomaterials.2012.02.031] [Citation(s) in RCA: 133] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Accepted: 02/14/2012] [Indexed: 02/07/2023]
Abstract
The goal of this study was to employ nano-graphene for tumor targeting in an animal tumor model, and quantitatively evaluate the pharmacokinetics and tumor targeting efficacy through positron emission tomography (PET) imaging using (66)Ga as the radiolabel. Nano-graphene oxide (GO) sheets with covalently linked, amino group-terminated six-arm branched polyethylene glycol (PEG; 10 kDa) chains were conjugated to NOTA (1,4,7-triazacyclononane-1,4,7-triacetic acid, for (66)Ga-labeling) and TRC105 (an antibody that binds to CD105). Flow cytometry analyses, size measurements, and serum stability studies were performed to characterize the GO conjugates before in vivo investigations in 4T1 murine breast tumor-bearing mice, which were further validated by histology. TRC105-conjugated GO was specific for CD105 in cell culture. (66)Ga-NOTA-GO-TRC105 and (66)Ga-NOTA-GO exhibited excellent stability in complete mouse serum. In 4T1 tumor-bearing mice, these GO conjugates were primarily cleared through the hepatobiliary pathway. (66)Ga-NOTA-GO-TRC105 accumulated quickly in the 4T1 tumors and tumor uptake remained stable over time (3.8 ± 0.4, 4.5 ± 0.4, 5.8 ± 0.3, and 4.5 ± 0.4 %ID/g at 0.5, 3, 7, and 24 h post-injection respectively; n = 4). Blocking studies with unconjugated TRC105 confirmed CD105 specificity of (66)Ga-NOTA-GO-TRC105, which was corroborated by biodistribution and histology studies. Furthermore, histological examination revealed that targeting of NOTA-GO-TRC105 is tumor vasculature CD105 specific with little extravasation. Successful demonstration of in vivo tumor targeting with GO, along with the versatile chemistry of graphene-based nanomaterials, makes them suitable nanoplatforms for future biomedical research such as cancer theranostics.
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Affiliation(s)
- Hao Hong
- Department of Radiology, University of Wisconsin-Madison, Madison, WI 53705-2275, USA
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Nayak TR, Andersen H, Makam VS, Khaw C, Bae S, Xu X, Ee PLR, Ahn JH, Hong BH, Pastorin G, Özyilmaz B. Graphene for controlled and accelerated osteogenic differentiation of human mesenchymal stem cells. ACS Nano 2011; 5:4670-8. [PMID: 21528849 DOI: 10.1021/nn200500h] [Citation(s) in RCA: 557] [Impact Index Per Article: 42.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Current tissue engineering approaches combine different scaffold materials with living cells to provide biological substitutes that can repair and eventually improve tissue functions. Both natural and synthetic materials have been fabricated for transplantation of stem cells and their specific differentiation into muscles, bones, and cartilages. One of the key objectives for bone regeneration therapy to be successful is to direct stem cells' proliferation and to accelerate their differentiation in a controlled manner through the use of growth factors and osteogenic inducers. Here we show that graphene provides a promising biocompatible scaffold that does not hamper the proliferation of human mesenchymal stem cells (hMSCs) and accelerates their specific differentiation into bone cells. The differentiation rate is comparable to the one achieved with common growth factors, demonstrating graphene's potential for stem cell research.
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Affiliation(s)
- Tapas R Nayak
- Department of Pharmacy, National University of Singapore, 3 Science Drive 2, Singapore 117543
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Nayak TR, Jian L, Phua LC, Ho HK, Ren Y, Pastorin G. Thin films of functionalized multiwalled carbon nanotubes as suitable scaffold materials for stem cells proliferation and bone formation. ACS Nano 2010; 4:7717-7725. [PMID: 21117641 DOI: 10.1021/nn102738c] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
In the field of regenerative medicine, human mesenchymal stem cells envisage extremely promising applications, due to their ability to differentiate into a wide range of connective tissue species on the basis of the substrate on which they grow. For the first time ever reported, we investigated the effects of a thin film of pegylated multiwalled carbon nanotubes spray dried onto preheated coverslips in terms of their ability to influence human mesenchymal stem cells' proliferation, morphology, and final differentiation into osteoblasts. Results clearly indicated that the homogeneous layer of functionalized nanotubes did not show any cytotoxicity and accelerated cell differentiation to a higher extent than carboxylated nanotubes or uncoated coverslips, by creating a more viable microenvironment for stem cells. Interestingly, cell differentiation occurred even in the absence of additional biochemical inducing agents, as evidenced by multiple independent criteria at the transcriptional, protein expression, and functional levels. Taken together, these findings suggest that functionalized carbon nanotubes represent a suitable scaffold toward a very selective differentiation into bone.
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Affiliation(s)
- Tapas R Nayak
- Department of Pharmacy, National University of Singapore, Block S15#05-PI-03, Singapore 117543
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Chowdhury C, Nayak TR, Young KD, Ghosh AS. A weak DD-carboxypeptidase activity explains the inability of PBP 6 to substitute for PBP 5 in maintaining normal cell shape in Escherichia coli. FEMS Microbiol Lett 2009; 303:76-83. [PMID: 20015336 DOI: 10.1111/j.1574-6968.2009.01863.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Penicillin-binding protein (PBP) 5 plays a critical role in maintaining normal cellular morphology in mutants of Escherichia coli lacking multiple PBPs. The most closely related homologue, PBP 6, is 65% identical to PBP 5, but is unable to substitute for PBP 5 in returning these mutants to their wild-type shape. The relevant differences between PBPs 5 and 6 are localized in a 20-amino acid stretch of domain I in these proteins, which includes the canonical KTG motif at the active site. We determined how these differences affected the enzymatic properties of PBPs 5 and 6 toward beta-lactam binding and the binding and hydrolysis of two peptide substrates. We also investigated the enzymatic properties of recombinant fusion proteins in which active site segments were swapped between PBPs 5 and 6. The results suggest that the in vivo physiological role of PBP 5 is distinguished from PBP 6 by the higher degree of DD-carboxypeptidase activity of the former.
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Affiliation(s)
- Chiranjit Chowdhury
- Department of Biotechnology, Indian Institute of Technology, Kharagpur, West Bengal, India
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