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Design and production of vaccines against COVID-19 using established vaccine platforms
Published in Amine Kamen, Laura Cervera, Bioprocessing of Viral Vaccines, 2023
Ryan Kligman, Jesús Lavado-García, Amine Kamen
The OA vaccine was originally designed as a single dose vaccine, but due to lower protection than expected (43% and 80% reduction in risk of emergent hospitalization and severe infection, respectively), a booster dose was suggested within 4–12 weeks of the initial dose. This booster dose resulted in an efficacy of 70.4% [49]. Clinical trials also demonstrated good safety results [50]. However, vaccine rollout was notably temporarily ceased in March 2021 after reports of thromboembolic events including several unexpected deaths. Among the 5 million vaccine recipients at the time, there were 30 cases of thrombotic events, mostly venous thromboembolisms that were believed to have occurred due to the generation of antibodies against platelet factor 4 resulting in a vaccine induced thrombotic thrombocytopenia similar to a heparin induced thrombocytopenia [51].
3D-Printed Nanodevices of Pharmaceutical and Biomedical Relevance
Published in Suvardhan Kanchi, Rajasekhar Chokkareddy, Mashallah Rezakazemi, Smart Nanodevices for Point-of-Care Applications, 2022
A microfluidic immunosensor was 3D printed to detect the biomarkers involved in prostate cancer. FDM was used in this study. RuBPY-silica nanoparticles were prepared and these nanoparticles were coated with poly(diallyldimethylammoniumchloride) and poly(acrylic acid). Three antigens, namely prostate-specific membrane antigen (PSMA), prostate-specific antigen (PSA) and platelet factor-4 (PF-4), are biomarkers in the detection of prostate cancer, hence their respective antibodies, namely anti-PSMA, anti-PSA and anti-PF-4asAb2, were used as detection antibodies. These antibodies were covalently tagged to a COOH group of poly(acrylic acid). These antibodies were coated on (RuBPY)-doped silica nanoparticles with the electro-chemiluminescent which generates light by the supercapacitor that is detected by the CCD camera. These antibodies were detected in the limit of 0.3–0.5 pgmL–1. Thus, 3D printing aids in the generation of biosensors, however, a number of steps were involved in its synthesis [101]. In a similar study to detect cancer, microfluidics was incorporated by 3D printing the microfluidic device. The device consists of three parts which include a reagent reservoir, a mixing aid and a detection chamber for evaluating the chemiluminescence output with a CCD camera. PSA and platelet factor 4 were used as antibodies for the study. Detection of cancer biomarkers requires 30 min with minimal operation. This study showed the scope for further improving the device as a point-of-care diagnostic tool for cancer [105].
Carbon Nanotubes as Chemical Sensors and Biosensors: A Review
Published in Alexander V. Vakhrushev, Suresh C. Ameta, Heru Susanto, A. K. Haghi, Advances in Nanotechnology and the Environmental Sciences, 2019
Rakshit Ameta, Kanchan Kumari Jat, Jayesh Bhatt, Avinash Rai, Tarachand Nargawe, Dipti Soni, Suresh C. Ameta
A prototype 4-unit electrochemical immunoarray based on SWCNT forests has been reported by Chikkaveeraiah et al. [82] for the simultaneous detection of multiple protein biomarkers for prostate cancer. They designed immunoarray procedures to measure prostate-specific antigen (PSA), prostate specific membrane antigen (PSMA), platelet factor–4 (PF–4), and interleukin–6 (IL–6) simultaneously in a single serum sample. All of these proteins are known to be elevated in serum of patients having prostate cancer. Horseradish peroxidase (HRP) was used as label on detection (secondary) antibodies in a sandwich immunoassay scheme. Biotinylated secondary antibodies (Ab2) binding specifically to streptavidin-HRP conjugates provided 14-16 labels per antibody, which gave the necessary higher sensitivity required for PF–4 and IL–6 detection at physiological levels. Conventional singly labeled Ab2-HRP conjugates were enough for PSA and PSMA detection. Immunoarrays were used to measure four biomarkers in human serum samples of prostate cancer patients controls and showed excellent correlation to referee enzyme-linked immunosorbent (ELISA) assays.
Immobilizing argatroban and mPEG-NH2 on a polyethersulfone membrane surface to prepare an effective nonthrombogenic biointerface
Published in Journal of Biomaterials Science, Polymer Edition, 2019
Yanling Dai, Siyuan Dai, Xiaohui Xie, Jianping Ning
Heparin has been extensively researched as a coating of biomaterial surfaces to inhibit thrombosis [3, 8, 18, 21, 22]. HeprAN, the membrane of the commercial Evodial dialyzer, uses improved AN69ST technology in which heparin is grafted to the membrane. Several studies show that the Evodial dialyzer can be used without the systemic administration of heparin for hemodialysis in patients with bleeding tendencies [23–27]. Although the HeprAN membrane has been proven to be non-inferior to saline infusion, the superiority of its treatment, has not been demonstrated [23, 28, 29]. Additionally, the anticoagulation effectiveness of heparin is dependent upon the patient plasma concentration of antithrombin (AT). Therefore, heparin cannot be used in patients with an AT deficiency and can only indirectly inhibit free plasma thrombin but cannot inhibit fibrin-bound thrombin [30–31]. Moreover, nonspecific binding to other molecules [32], including plasma proteins and platelet factor 4 (PF4), not only reduces the availability of heparin to bind AT but can also induce side effects [31, 33], such as heparin-induced thrombocytopenia (HIT, an adverse immune-mediated drug reaction by an anti-heparin/PF4 complex antibody), which may further increase the risk of bleeding in patients with hemorrhage complications.