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Galvez NMS, Sheehan ML, Lin AZ, Cao Y, Lam EC, Jackson AM, Balazs AB. QuickFit: A High-Throughput RT-qPCR-Based Assay to Quantify Viral Growth and Fitness In Vitro. Viruses 2024; 16:1320. [PMID: 39205294 PMCID: PMC11360610 DOI: 10.3390/v16081320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2024] [Revised: 08/14/2024] [Accepted: 08/15/2024] [Indexed: 09/04/2024] Open
Abstract
Quantifying viral growth rates is key to understanding evolutionary dynamics and the potential for mutants to escape antiviral drugs. Defining evolutionary escape paths and their impact on viral fitness allows for the development of drugs that are resistant to escape. In the case of HIV, combination antiretroviral therapy can successfully prevent or treat infection, but it relies on strict adherence to prevent escape. Here, we present a method termed QuickFit that enables the quantification of viral fitness by employing large numbers of parallel viral cultures to measure growth rates accurately. QuickFit consistently recapitulated HIV growth measurements obtained by traditional approaches, but with significantly higher throughput and lower rates of error. This method represents a promising tool for rapid and consistent evaluation of viral fitness.
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Affiliation(s)
| | | | | | | | | | | | - Alejandro B. Balazs
- Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology, Harvard University, Cambridge, MA 02139, USA
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Safenkova IV, Burkin KM, Bodulev OL, Razo SC, Ivanov AV, Zherdev AV, Dzantiev BB, Sakharov IY. Comparative study of magnetic beads and microplates as supports in heterogeneous amplified assay of miRNA-141 by using mismatched catalytic hairpin assembly reaction. Talanta 2022; 247:123535. [DOI: 10.1016/j.talanta.2022.123535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 04/08/2022] [Accepted: 05/06/2022] [Indexed: 11/16/2022]
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Maeno H, Wong PF, AbuBakar S, Yang M, Sam SS, Jamil-Abd J, Shunmugarajoo A, Mustafa M, Said RM, Mageswaren E, Azmel A, Mat Jelani A. A 3D Microfluidic ELISA for the Detection of Severe Dengue: Sensitivity Improvement and Vroman Effect Amelioration by EDC-NHS Surface Modification. MICROMACHINES 2021; 12:mi12121503. [PMID: 34945351 PMCID: PMC8715748 DOI: 10.3390/mi12121503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 11/20/2021] [Accepted: 11/29/2021] [Indexed: 11/16/2022]
Abstract
Serum is commonly used as a specimen in immunoassays but the presence of heterophilic antibodies can potentially interfere with the test results. Previously, we have developed a microfluidic device called: 3D Stack for enzyme-linked immunosorbent assay (ELISA). However, its evaluation was limited to detection from a single protein solution. Here, we investigated the sensitivity of the 3D Stack in detecting a severe dengue biomarker—soluble CD163 (sCD163)—within the serum matrix. To determine potential interactions with serum matrix, a spike-and-recovery assay was performed, using 3D Stacks with and without surface modification by an EDC–NHS (N-ethyl-N′-(3-(dimethylamino)propyl)carbodiimide/N-hydroxysuccinimide) coupling. Without surface modification, a reduced analyte recovery in proportion to serum concentration was observed because of the Vroman effect, which resulted in competitive displacement of coated capture antibodies by serum proteins with stronger binding affinities. However, EDC–NHS coupling prevented antibody desorption and improved the sensitivity. Subsequent comparison of sCD163 detection using a 3D Stack with EDC–NHS coupling and conventional ELISA in dengue patients’ sera revealed a high correlation (R = 0.9298, p < 0.0001) between the two detection platforms. Bland–Altman analysis further revealed insignificant systematic error between the mean differences of the two methods. These data suggest the potentials of the 3D Stack for further development as a detection platform.
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Affiliation(s)
- Hinata Maeno
- Department of System Design, Tokyo Metropolitan University, Tokyo 191-0065, Japan;
| | - Pooi-Fong Wong
- Department of Pharmacology, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia;
| | - Sazaly AbuBakar
- Tropical Infectious Diseases Research and Educational Centre (TIDREC), University of Malaya, Kuala Lumpur 50603, Malaysia; (S.A.); (S.-S.S.); (J.J.-A.)
- WHO Collaborating Centre for Arbovirus Reference and Research (Dengue and Severe Dengue) MAA-12, University of Malaya, Kuala Lumpur 50603, Malaysia
- Medical Department, Tengku Ampuan Rahimah Hospital, Klang 41200, Malaysia; (A.S.); (E.M.); (A.A.)
| | - Ming Yang
- Department of System Design, Tokyo Metropolitan University, Tokyo 191-0065, Japan;
- Correspondence:
| | - Sing-Sin Sam
- Tropical Infectious Diseases Research and Educational Centre (TIDREC), University of Malaya, Kuala Lumpur 50603, Malaysia; (S.A.); (S.-S.S.); (J.J.-A.)
- WHO Collaborating Centre for Arbovirus Reference and Research (Dengue and Severe Dengue) MAA-12, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Juraina Jamil-Abd
- Tropical Infectious Diseases Research and Educational Centre (TIDREC), University of Malaya, Kuala Lumpur 50603, Malaysia; (S.A.); (S.-S.S.); (J.J.-A.)
- WHO Collaborating Centre for Arbovirus Reference and Research (Dengue and Severe Dengue) MAA-12, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Anusha Shunmugarajoo
- Medical Department, Tengku Ampuan Rahimah Hospital, Klang 41200, Malaysia; (A.S.); (E.M.); (A.A.)
| | - Mahiran Mustafa
- Medical Department, Raja Perempuan Zainab II Hospital, Kota Bharu 15200, Malaysia; (M.M.); (A.M.J.)
| | - Rosaida Md Said
- Medical Department, Ampang Hospital, Ampang 68000, Malaysia;
| | - Eashwary Mageswaren
- Medical Department, Tengku Ampuan Rahimah Hospital, Klang 41200, Malaysia; (A.S.); (E.M.); (A.A.)
| | - Azureen Azmel
- Medical Department, Tengku Ampuan Rahimah Hospital, Klang 41200, Malaysia; (A.S.); (E.M.); (A.A.)
| | - Anilawati Mat Jelani
- Medical Department, Raja Perempuan Zainab II Hospital, Kota Bharu 15200, Malaysia; (M.M.); (A.M.J.)
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Sutcliffe AC, Irish SR, Rogier E, Finney M, Zohdy S, Dotson EM. Adaptation of ELISA detection of Plasmodium falciparum and Plasmodium vivax circumsporozoite proteins in mosquitoes to a multiplex bead-based immunoassay. Malar J 2021; 20:377. [PMID: 34556130 PMCID: PMC8461957 DOI: 10.1186/s12936-021-03910-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 09/09/2021] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Plasmodium spp. sporozoite rates in mosquitoes are used to better understand malaria transmission intensity, the relative importance of vector species and the impact of interventions. These rates are typically estimated using an enzyme-linked immunosorbent assay (ELISA) utilizing antibodies against the circumsporozoite protein of Plasmodium falciparum, Plasmodium vivax VK210 (P. vivax210) or P. vivax VK247 (P. vivax247), employing assays that were developed over three decades ago. The ELISA method requires a separate assay plate for each analyte tested and can be time consuming as well as requiring sample volumes not always available. The bead-based multiplex platform allows simultaneous measurement of multiple analytes and may improve the lower limit of detection for sporozoites. METHODS Recombinant positive controls for P. falciparum, P. vivax210 and P. vivax247 and previously developed circumsporozoite (cs) ELISA antibodies were used to optimize conditions for the circumsporozoite multiplex bead assay (csMBA) and to determine the detection range of the csMBA. After optimizing assay conditions, known amounts of sporozoites were used to determine the lower limit of detection for the csELISA and csMBA and alternate cut-off measures were applied to demonstrate how cut-off criteria can impact lower limits of detection. Sporozoite rates from 1275 mosquitoes collected in Madagascar and 255 mosquitoes collected in Guinea were estimated and compared using the established csELISA and newly optimized csMBA. All mosquitoes were tested (initial test), and those that were positive were retested (retest). When sufficient sample volume remained, an aliquot of homogenate was boiled and retested (boiled retest), to denature any heat-unstable cross-reactive proteins. RESULTS Following optimization of the csMBA, the lower limit of detection was 25 sporozoites per mosquito equivalent for P. falciparum, P. vivax210 and P. vivax247 whereas the lower limits of detection for csELISA were found to be 1400 sporozoites for P. falciparum, 425 for P. vivax210 and 1650 for P. vivax247. Combined sporozoite rates after re-testing of samples that initially tested positive for Madagascar mosquitoes by csELISA and csMBA were 1.4 and 10.3%, respectively, and for Guinea mosquitoes 2% by both assays. Boiling of samples followed by csMBA resulted in a decrease in the Madagascar sporozoite rate to 2.8-4.4% while the Guinea csMBA sporozoite rate remained at 2.0%. Using an alternative csMBA cut-off value of median fluorescence intensity (MFI) of 100 yielded a sporozoite rate after confirmational testing of 3.7% for Madagascar samples and 2.0% for Guinea samples. Whether using csMBA or csELISA, the following steps may help minimize false positives: specimens are appropriately stored and bisected anterior to the thorax-abdomen junction, aliquots of homogenate are boiled and retested following initial testing, and an appropriate cut-off value is determined. CONCLUSIONS The csMBA is a cost-comparable and time saving alternative to the csELISA and may help eliminate false negatives due to a lower limit of detection, thus increasing sensitivity over the csELISA. The csMBA expands the potential analyses that can be done with a small volume of sample by allowing multiplex testing where analytes in addition to P. falciparum, P. vivax210 and P. vivax247 can be added following optimization.
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Affiliation(s)
- Alice C Sutcliffe
- The Centers for Disease Control and Prevention, Division of Parasitic Diseases and Malaria, Entomology Branch, Atlanta, GA, USA.
| | - Seth R Irish
- The Centers for Disease Control and Prevention, Division of Parasitic Diseases and Malaria, Entomology Branch, Atlanta, GA, USA
- President's Malaria Initiative, Atlanta, GA, USA
| | - Eric Rogier
- The Centers for Disease Control and Prevention, Division of Parasitic Diseases and Malaria, Malaria Branch, Atlanta, GA, USA
| | - Micaela Finney
- College of Science and Mathematics, Auburn University, Auburn, AL, USA
- Entomology Department, College of Agriculture, Texas A&M University, College Station, TX, USA
| | - Sarah Zohdy
- The Centers for Disease Control and Prevention, Division of Parasitic Diseases and Malaria, Malaria Branch, Atlanta, GA, USA
- School of Forestry and Wildlife Sciences, Auburn University, Auburn, AL, USA
- College of Veterinary Medicine, Auburn University, Auburn, AL, USA
| | - Ellen M Dotson
- The Centers for Disease Control and Prevention, Division of Parasitic Diseases and Malaria, Entomology Branch, Atlanta, GA, USA
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Consequences of the Edge Effect in a Commercial Enzyme-Linked Immunosorbent Assay for the Diagnosis of Lyme Neuroborreliosis. J Clin Microbiol 2021; 59:e0328020. [PMID: 33980651 PMCID: PMC8288263 DOI: 10.1128/jcm.03280-20] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The diagnosis of Lyme neuroborreliosis (LNB) is based on neurological symptoms, cerebrospinal fluid (CSF) pleocytosis, and intrathecally produced Borrelia-specific antibodies. In most cases, the presence of intrathecally produced Borrelia-specific antibodies is determined by using an enzyme-linked immunosorbent assay (ELISA). The edge effect is a known phenomenon in ELISAs and can negatively influence the assay reproducibility and repeatability, as well as index calculations of sample pairs which are tested in the same run. For LNB diagnostics, an index calculation is used for which the relative amounts of Borrelia-specific antibodies in CSF and serum are measured to calculate a CSF/serum quotient, which is needed to calculate the Borrelia-specific antibody index (AI). The presence of an edge effect in an ELISA used for LNB diagnostics may thus have implications. In this study, we investigated the intra-assay variation of the commercial Enzygnost Lyme link VlsE/IgG ELISA used for LNB diagnostics and showed the presence of an edge effect. Minor adaptations in the ELISA protocol decreased this effect. The adapted protocol was subsequently used to test 149 CSF-serum pairs of consecutive patients received in a routine diagnostic laboratory. By simulation, we showed that, if the standard protocol would have been used, then the edge effect for this study population could have resulted in 15 (10.1%) false-pathological and two (1.3%) false-normal Borrelia-specific IgG AIs. Thus, the observed edge effect can lead to inaccurate LNB diagnoses. Our study underlines that the edge effect should be investigated when ELISAs are implemented in routine diagnostics, as this phenomenon can occur in any ELISA.
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Epitope-directed monoclonal antibody production using a mixed antigen cocktail facilitates antibody characterization and validation. Commun Biol 2021; 4:441. [PMID: 33824395 PMCID: PMC8024308 DOI: 10.1038/s42003-021-01965-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 03/08/2021] [Indexed: 02/01/2023] Open
Abstract
High quality, well-validated antibodies are needed to mitigate irreproducibility and clarify conflicting data in science. We describe an epitope-directed monoclonal antibody (mAb) production method that addresses issues of antibody quality, validation and utility. The workflow is illustrated by generating mAbs against multiple in silico-predicted epitopes on human ankyrin repeat domain 1 (hANKRD1) in a single hybridoma production cycle. Antigenic peptides (13-24 residues long) presented as three-copy inserts on the surface exposed loop of a thioredoxin carrier produced high affinity mAbs that are reactive to native and denatured hANKRD1. ELISA assay miniaturization afforded by novel DEXT microplates allowed rapid hybridoma screening with concomitant epitope identification. Antibodies against spatially distant sites on hANKRD1 facilitated validation schemes applicable to two-site ELISA, western blotting and immunocytochemistry. The use of short antigenic peptides of known sequence facilitated direct epitope mapping crucial for antibody characterization. This robust method motivates its ready adoption for other protein targets.
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Dauer K, Pfeiffer-Marek S, Kamm W, Wagner KG. Microwell Plate-Based Dynamic Light Scattering as a High-Throughput Characterization Tool in Biopharmaceutical Development. Pharmaceutics 2021; 13:pharmaceutics13020172. [PMID: 33514069 PMCID: PMC7911513 DOI: 10.3390/pharmaceutics13020172] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 01/12/2021] [Accepted: 01/22/2021] [Indexed: 01/03/2023] Open
Abstract
High-throughput light scattering instruments are widely used in screening of biopharmaceutical formulations and can be easily incorporated into processes by utilizing multi-well plate formats. High-throughput plate readers are helpful tools to assess the aggregation tendency and colloidal stability of biological drug candidates based on the diffusion self-interaction parameter (kD). However, plate readers evoke issues about the precision and variability of determined data. In this article, we report about the statistical evaluation of intra- and inter-plate variability (384-well plates) for the kD analysis of protein and peptide solutions. ANOVA revealed no significant differences between the runs. In conclusion, the reliability and precision of kD was dependent on the plate position of the sample replicates and kD value. Positive kD values (57.0 mL/g, coefficients of variation (CV) 8.9%) showed a lower variability compared to negative kD values (−14.8 mL/g, CV 13.4%). The variability of kD was not reduced using more data points (120 vs. 30). A kD analysis exclusively based on center wells showed a lower CV (<2%) compared to edge wells (5–12%) or a combination of edge and center wells (2–5%). We present plate designs for kD analysis within the early formulation development, screening up to 20 formulations consuming less than 50 mg of active pharmaceutical ingredient (API).
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Affiliation(s)
- Katharina Dauer
- Department of Pharmaceutical Technology and Biopharmaceutics, University of Bonn, 53121 Bonn, Germany;
- Tides Drug Product Pre-Development Sciences, Sanofi-Aventis Deutschland GmbH, Industrial Park Hoechst, 65926 Frankfurt am Main, Germany; (S.P.-M.); (W.K.)
| | - Stefania Pfeiffer-Marek
- Tides Drug Product Pre-Development Sciences, Sanofi-Aventis Deutschland GmbH, Industrial Park Hoechst, 65926 Frankfurt am Main, Germany; (S.P.-M.); (W.K.)
| | - Walter Kamm
- Tides Drug Product Pre-Development Sciences, Sanofi-Aventis Deutschland GmbH, Industrial Park Hoechst, 65926 Frankfurt am Main, Germany; (S.P.-M.); (W.K.)
| | - Karl G. Wagner
- Department of Pharmaceutical Technology and Biopharmaceutics, University of Bonn, 53121 Bonn, Germany;
- Correspondence:
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Essex A, Pineda J, Acharya G, Xin H, Evans J. Replication Study: Wnt activity defines colon cancer stem cells and is regulated by the microenvironment. eLife 2019; 8:e45426. [PMID: 31215867 PMCID: PMC6584130 DOI: 10.7554/elife.45426] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 06/07/2019] [Indexed: 01/05/2023] Open
Abstract
As part of the Reproducibility Project: Cancer Biology we published a Registered Report (Evans et al., 2015), that described how we intended to replicate selected experiments from the paper 'Wnt activity defines colon cancer stem cells and is regulated by the microenvironment' (Vermeulen et al., 2010). Here, we report the results. Using three independent primary spheroidal colon cancer cultures that expressed a Wnt reporter construct we observed high Wnt activity was associated with the cell surface markers CD133, CD166, and CD29, but not CD24 and CD44, while the original study found all five markers were correlated with high Wnt activity (Figure 2F; Vermeulen et al., 2010). Clonogenicity was highest in cells with high Wnt activity and clonogenic potential of cells with low Wnt activity were increased by myofibroblast-secreted factors, including HGF. While the effects were in the same direction as the original study (Figure 6D; Vermeulen et al., 2010) whether statistical significance was reached among the different conditions varied. When tested in vivo, we did not find a difference in tumorigenicity between high and low Wnt activity, while the original study found cells with high Wnt activity were more effective in inducing tumors (Figure 7E; Vermeulen et al., 2010). Tumorigenicity, however, was increased with myofibroblast-secreted factors, which was in the same direction as the original study (Figure 7E; Vermeulen et al., 2010), but not statistically significant. Finally, we report meta-analyses for each results where possible.
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Affiliation(s)
| | | | | | - Hong Xin
- Explora BioLabs Inc, San Diego, United States
| | - James Evans
- PhenoVista Biosciences, San Diego, United States
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Bordeleau E, Mazinani SA, Nguyen D, Betancourt F, Yan H. Abrasive treatment of microtiter plates improves the reproducibility of bacterial biofilm assays. RSC Adv 2018; 8:32434-32439. [PMID: 35547717 PMCID: PMC9086168 DOI: 10.1039/c8ra06352d] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 09/12/2018] [Indexed: 11/30/2022] Open
Abstract
Microtiter plate-based bacterial biofilm assay is frequently used to study bacterial biofilm development and growth. While this assay is simple and relatively high-throughput, it frequently shows difficulty in establishing robust biofilm attachment in the wells. We report that the consistency of bacterial biofilm assays carried out in microtiter plates subjected to abrasive treatment, by sandblasting or drill press grinding, is significantly improved in a Pseudomonas fluorescens Pf0-1 model. Scanning electron microscopy imaging suggests that the treated surfaces could provide points of attachment to facilitate the recruitment of bacteria in the initial phase of biofilm colony establishment. The sandblast treated polypropylene, but not polystyrene, plates were found suitable in studying the impact of flavonoid quercetin on the biofilm formation in Bacillus subtilis FB17. Further investigation revealed that due to the hydrophobicity of the polystyrene surfaces, a greater amount of quercetin was adsorbed on the plate surface, effectively lowering the concentration of the flavonoid in solution. The reproducibility of bacterial biofilm assays is improved using abrasively-treated microtiter plates.![]()
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Affiliation(s)
- Emily Bordeleau
- Department of Chemistry and Centre for Biotechnology, Brock University 1812 Sir Isaac Brock Way St. Catharines Ontario Canada L2S 3A1
| | - Sina Atrin Mazinani
- Department of Chemistry and Centre for Biotechnology, Brock University 1812 Sir Isaac Brock Way St. Catharines Ontario Canada L2S 3A1
| | - David Nguyen
- Department of Chemistry and Centre for Biotechnology, Brock University 1812 Sir Isaac Brock Way St. Catharines Ontario Canada L2S 3A1
| | - Frank Betancourt
- Department of Chemistry and Centre for Biotechnology, Brock University 1812 Sir Isaac Brock Way St. Catharines Ontario Canada L2S 3A1
| | - Hongbin Yan
- Department of Chemistry and Centre for Biotechnology, Brock University 1812 Sir Isaac Brock Way St. Catharines Ontario Canada L2S 3A1
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Giannos SA, Kraft ER, Zhao ZY, Merkley KH, Cai J. Photokinetic Drug Delivery: Near infrared (NIR) Induced Permeation Enhancement of Bevacizumab, Ranibizumab and Aflibercept through Human Sclera. Pharm Res 2018; 35:110. [PMID: 29600470 PMCID: PMC5876416 DOI: 10.1007/s11095-018-2392-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Accepted: 03/19/2018] [Indexed: 01/04/2023]
Abstract
PURPOSE Permeation studies, with near infrared (NIR) light and anti-aggregation antibody formulation, were used to investigate the in vitro permeation of bevacizumab, ranibizumab and aflibercept through human sclera. METHODS A vertical, spherical Franz cell diffusion apparatus was used for this scleral tissue permeation model. A photokinetic ocular drug delivery (PODD) testing device accommodated the placement of NIR LEDs above the donor chambers. An adjustable LED driver/square wave generator provided electrical energy with a variable pulse rate and pulse width modulation (duty cycle). RESULTS Exposure to non-thermal NIR light had no effect on mAbs with regard to monomer concentration or antibody binding potential, as determined by SE-HPLC and ELISA. The optimal LED wavelength was found to be 950 nm. Duty cycle power of 5% vs 20% showed no difference in permeation. When compared to controls, the combination of non-aggregating antibody formulation and NIR illumination provided an average transscleral drug flux enhancement factor of 3X. CONCLUSION Narrow wavelength incoherent (non-laser) light from an NIR LED source is not harmful to mAbs and can be used to enhance drug permeation through scleral tissue. The topical formulation, combined with pulsed NIR light irradiation, significantly improved scleral permeation of three anti-VEGF antibody drugs.
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Affiliation(s)
- Steven A Giannos
- Department of Ophthalmology and Visual Sciences, University of Texas Medical Branch, 301 University Blvd, Galveston, Texas, 77555, USA.
| | - Edward R Kraft
- Department of Ophthalmology and Visual Sciences, University of Texas Medical Branch, 301 University Blvd, Galveston, Texas, 77555, USA
| | - Zhen-Yang Zhao
- Department of Ophthalmology and Visual Sciences, University of Texas Medical Branch, 301 University Blvd, Galveston, Texas, 77555, USA
| | - Kevin H Merkley
- Department of Ophthalmology and Visual Sciences, University of Texas Medical Branch, 301 University Blvd, Galveston, Texas, 77555, USA
| | - Jiyang Cai
- Department of Ophthalmology and Visual Sciences, University of Texas Medical Branch, 301 University Blvd, Galveston, Texas, 77555, USA
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Katariya M, Chung DCK, Minife T, Gupta H, Zahidi AAA, Liew OW, Ng TW. Drone inflight mixing of biochemical samples. Anal Biochem 2018; 545:1-3. [DOI: 10.1016/j.ab.2018.01.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 12/29/2017] [Accepted: 01/02/2018] [Indexed: 01/17/2023]
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