Open Access Pub publishes peer-reviewed, free-to-read open-access articles. Showing
articles matching ELISA. — open any to read the full text,
or download the PDF or XML.
Aug 2021 DOI 10.14302/issn.2326-0793.jpgr-21-3917
Tarassishin LeonidCorresponding author
Department of Pathology, Albert Einstein College of Medicine, United States.
50 years ago the Enzyme Immunoassay Enzyme-Linked Immunosorbent Assay, mostly known as ELISA was developed. This is a powerful but simple method that is very widely used in the diagnostic practice, as well as in biomedical research. During this time a number of ELISA modification were developed that significantly increased its properties, especially the senstivity, such as avidin-biotin assay, immuno-PCR, nano-ELISA and finally, the digital ELISA. This short review describes the principles of ELISA and the evolution from a conventional assay to the modern ultra-sensitive method. Most of the immunological methods have two components: antigen and antibody. The high specificity of their interaction gives a possibility to detect one of them if other one is included in the reaction as a specific partner. The simplest method for antigen detection in the presence of the antibody is immune diffusion (radial immune diffusion in that case), which practically the formation of precipitate of the “antigen-antibody” complex, when the target antigen diffuses from well into agarose containing the specific antibody. Unfortunately, this assay, as well as other traditional methods, like hemagglutination or complement fixation, have a low sensitivity and are unwieldy.
Jul 2021 DOI 10.14302/issn.2766-8681.jcsr-21-3885
Jana SnehasisCorresponding author
Trivedi Science Research Laboratory Pvt. Ltd., Thane (W), Maharashtra, India.
Sepsis is a systemic inflammatory response to a confirmed or suspected infection. The transition from sepsis to septic shock causes high rate of mortality. The aim of this experiment was to evaluate the anti-inflammatory potential of the Biofield Energy Treated (Blessed) Proprietary Test Formulation and Biofield Energy Healing (Blessing) Treatment per se to Sprague Dawley rats on Cecal Slurry, LPS, and E. coli-induced systemic inflammatory response syndrome (SIRS) model. In this experiment, various proinflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, IL-10, IL-12, 1L-17, and interferon-γ (IFN-γ) were analysed using ELISA. A test formulation was formulated including minerals (magnesium, zinc, calcium, selenium, and iron), vitamins (ascorbic acid, pyridoxine HCl, vitamin E, cyanocobalamin, and cholecalciferol), Panax ginseng extract, β-carotene, and cannabidiol isolate. The constituents of the test formulation were divided into two parts; one section was defined as the untreated test formulation, while the other portion of the test formulation and three group of animals received Biofield Energy Healing Treatment remotely for about 3 minutes by a renowned Biofield Energy Healer Mr. Mahendra Kumar Trivedi. The level of TNF-α was significantly reduced by 40.50%, 85.36% (p≤0.01), 50.66% (p≤0.01), 87.38% (p≤0.01), and 58.63% (p≤0.01) in G5 (Cecal Slurry, LPS, and E. coli + Biofield Energy Treated test formulation), G6 (Cecal Slurry, LPS, and E. coli + Biofield Energy Treatment per se to animals from day -15), G7 (Cecal Slurry, LPS, and E. coli + Biofield Energy Treated test formulation from day -15), G8 (Cecal Slurry, LPS, and E. coli + Biofield Energy Treatment per se + Biofield Energy Treated test formulation from day -15), and G9 (Cecal Slurry, LPS, and E. coli + Biofield Energy Treatment per se animals + untreated test formulation) groups, respectively as compared to the disease control (G2) group. Additionally, the level of IL-1β was decreased by 17.04%, 15.56%, and 12.59% in G6, G8, and G9 groups, respectively as compared to the untreated test formulation (G4) group. The level of IL-6 was significantly (p≤0.001) reduced by 36.18%, 50.24%, 43.25%, 52.69%, and 38.23% in the G5, G6, G7, G8, and G9 groups, respectively as compared to the G2 group. The level of IL-10 was altered by 70.53%, 49.25%, 60.18%, 41.54%, and 58.89% in G5, G6, G7, G8, and G9 groups, respectively as compared to the G2 group. Moreover, the level of IL-12 was decreased by 30.24%, 31.67%, 29.82%, 45.77%, and 50.54% in the G5, G6, G7, G8, and G9 groups, respectively as compared to the G2. The level of IL-17 was reduced by 48.75%, 59.61%, 59.28%, 62.49%, and 58.65% in the G5, G6, G7, G8, and G9 groups, respectively as compared to the G2. IFN-γ expression was reduced by 49.56%, 24.09%, 23.7%, 56.98%, and 44.94% in G5, G6, G7, G8, and G9 groups, respectively than G2. Overall, the data suggested anti-inflammatory potentials of the Biofield Energy Treated test formulation and Biofield Energy Treatment per se along with preventive measure on the animal with respect to various inflammatory conditions that might be beneficial various types of systemic inflammatory disorders specially sepsis, trauma, septic shock or any types of injuries. Therefore, the results showed the significant slowdown the inflammation-related disease progression and its complications in preventive treatment groups viz. G6, G7, G8, and G9.
Apr 2020 DOI 10.14302/issn.2372-6601.jhor-20-3189
Mamadou Sekongo YassonguiCorresponding author
Department of Training and Research, National Blood Transfusion Center; Abidjan; Côte D’Ivoire
This article has been retracted on 29 January 2021. VIEW THE RETRACTION NOTICE (https://doi.org/10.14302/issn.2372-6601.jhor-25-5854) In Côte d'Ivoire, sickle cell disease affects 14% of the population. It is responsible for significant morbidity and mortality. Transfusion is a significant element in the management of major sickle cell anemia, which exposes them to post-transfusion hemochromatosis. The biological diagnosis is based on the determination of serum iron and the transferrin saturation coefficient (CST). As the determination of the CST was not available in our exercise context in Côte d'Ivoire, we determined only the ferritinemia. The interest of this work lies in the therapeutic implication linked to the identification of patients at risk of hemochromatosis because chelators are difficult to access for most patients. This was a prospective, descriptive and analytical study, on polytransfused sickle cell patients, followed at the transfusion therapy unit (UTT) of the CNTS of Abidjan, from 2010 to 2018. We included 78 sickle cell patients, all ages and genders who have received at least ten transfusions. The ferritinemia assay was carried out by ELISA. Transfusion exchange, with 59% of cases, was the most used mode of transfusion. The mean ferritinemia was 1719.19 ng / ml. Hyperferritinemia was found in 63% of patients. Most of the patients were on a long-term transfusion program with an average of 27.5 bags of red blood cell concentrates. Thirty-two patients had received at least 20 bags of red blood cell concentrates. We noted 21 patients treated, including 3 with deferoxamine and 18 treated with oral deferasirox. We have identified 33 sickle cell anemia patients at risk for hemochromatosis. The determinants of the risk of hemochromatosis were the high number of blood bags and the method of transfusion.
Dec 2018 DOI 10.14302/issn.2377-2549.jndc-18-2430
P. Richie Jr JohnCorresponding author
Department of Public Health Sciences, Penn State College of Medicine, Hershey, PA 17033
Introduction: Analysis of 8-oxodG is usually conducted by either chromatography-based methods or by immunochemical methods commonly used based upon their low cost and high-throughput. However, concern regarding the accuracy of ELISA methods has complicated their use. We directly compare the levels of urinary 8-oxodG obtained by HPLC-MS/MS with three commercially available ELISA kits in this report. Methods: In the current study, a total of 9 human urine samples were analyzed by LC-MS/MS and three commonly used commercial available ELISA kits. Results: We found that urinary 8-oxodG levels analyzed by HPLC-MS/MS [1.4 ± 0.3 nmol/mmol creatinine) were 7.6- to 23.5-fold lower than those detected by ELISA. Overall, the correlations between ELISA and HPLC-MS/MS were poor but were improved after SPE purification for kits from ENZO (P = 0.2817 without SPE; P = 0.0086 with SPE) and Abcam (P = 0.0596 without SPE; P = 0.0473 with SPE). Discussion and Conclusion: While we confirmed that SPE purification can improve the correlation between the selected ELISA kits and HPLC-MS/MS, HPLC-MS/MS is still the method of choice to accurately assess the levels of 8-oxodG in human urine.
Dec 2018 DOI 10.14302/issn.2575-1212.jvhc-18-2487
Fernando Díaz-OteroCorresponding author
Centro Nacional de Investigaciones Disciplinarias en Microbiología Animal, Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias. Carretera México-Toluca, Km. 15.5, C.P. 05110, México D.F.
Parasitic infection by the Fasciola hepatica (F. hepatica) promotes susceptibility towards other infections, such as Mycobacterium bovis. As consequence, could affect diagnostic tests for this disease. Hence, the objective of this study was to assess the impact of F. hepatica coinfection on the most commonly used immunodiagnostic bovine tuberculosis (bTB) tests in field conditions in an enzootic area for both diseases. Thus, from a dairy herd located in Hidalgo State, México, displaying a 59.2% and 28% prevalence of fascioliasis and bTB, respectively. Sixty-one cows were analyzed based on their response towards bTB immunodiagnostic tests, such as Single Intradermal Comparative Tuberculin Test (SICTT), gamma-interferon test (BOVIGAM) and enzyme-linked immunosorbent assay (ELISA), along with the assessment of the F. hepatica parasite load and serodiagnosis by ELISA. Three study groups were formed according to test results. Group 1: coinfected (n=22). Group 2: non-parasitized cows, and positive for bTB tests (n=13) and Group 3: parasitized cows without tuberculosis (n=26). In addition, a group of cows kept in fascioliasis - and tuberculosis-free zones were included (Group 4, n=10). A non-parametric Kruskal-Wallis test and a Dunn test were applied to analyze the results. In Group 1, significant differences were observed regarding IFN-γ production, but not for antibody levels to M. bovis or reactivity towards bovine PPD in relation Group 2. While, Groups 1 and 3 did not display difference in antibody levels against F. hepatica. Differences were observed regarding tuberculosis and Fasciola diagnostic tests when both coinfected and infected groups were compared to controls. It is concluded that F. hepatica coinfection in tuberculous animals studied, depressed the production of IFN-γ towards bovine PPD under in vitro conditions, but its reactivity to the SICTT not show to be altered.
Aug 2017 DOI 10.14302/issn.2575-1212.jvhc-17-1661
Parreño VivianaCorresponding author
National Council of Scientific and Technical Research - CONICET, Buenos Aires, Argentina.
Serum samples from wild and domestic South American Camelids (SAC) from Argentina, collected before (2008), during (2009) and after (2010) the 2009 H1N1 influenza pandemic were tested by hemagglutination-inhibition assay (HIA) to evaluate the seroprevalence of antibodies (Ab) against different subtypes of influenza A viruses: A(H1N1)pdm09, A/sw/Argentina/SIV/2009(H3N2) and A/eq/Argentina/97(H3N8). For A(H1N1), an ELISA using a recombinant H1-hemmaglutinin from a reference strain (HA0 PuertoRico/8/1934) was also conducted. Serum samples from Guanacos (126), vicugnas (21) and llamas (100) from Jujuy, Mendoza and Río Negro provinces were analyzed; no clinical signs of respiratory disease were detected, reason for which no nasal swabs were obtained. No seropositive reactors to H3N2 nor H3N8 variants were detected, nevertheless high incidence of Ab reactive to A(H1N1)pdm09 were found by HIA; results which were confirmed by ELISA. The Ab seropositive animals to H1-like IAV found in llamas from Jujuy, and Mendoza (2009) were 78% and 86% by HIA and ELISA, respectively. Thirty-seven samples taken over the three years from guanacos kept in captivity in Rio Negro showed 62% of seropositive animals, while wild guanacos from Mendoza sampled in 2010 showed 36% seropositive animals to H1-like IAV, by both techniques. Finally, wild vicugnas from Jujuy, sampled in 2008 showed 38% and 52% seropositive animals to H1-like IAV by HIA and ELISA, respectively. Our results could indicate the potential role of these species as a reservoir of this zoonotic viral agent of high impact in Public Health, and may suggest that SAC populations might have been infected with an influenza strain antigenically related to H1 IAV. . Surprisingly, for llama and guanaco populations sampled over time in Jujuy and Río Negro, respectively, the HIA and ELISA geometric mean Ab titers (GMT) for 2008 were significantly higher than the ones of 2010. In addition, HIA and ELISA Ab titers found in domestic llamas were significantly higher than those detected in wild vicugnas sampled during that year (2008) in Jujuy. New field campaigns are in progress to collect serum samples and nasal swabs in order to isolate and characterize the virus responsible for triggering H1 reactive Abs. These findings remark the need to better understand the dynamics and ecology of influenza A virus within Sacs populations.
Aug 2017 DOI 10.14302/issn.2638-4469.japb-17-1563
Wanke DierkCorresponding author
Universität des Saarlandes, Molekulare Pflanzenbiologie, Campus A2.4, 66123 Saarbrücken, Germany
GAGA-binding proteins in plants are encoded by the BARLEY B-RECOMBINANT / BASIC PENTACYSTEINE (BBR/BPC) family, which can be spilt into several groups on the basis of sequence divergence. The proteins of the different groups share an evolutionary conserved BASIC PENTACYSTEINE (BPC) domain at their very C-terminus that is important for DNA binding. Hallmark of this domain are five Cysteines at defined positions and spacing, which are considered to form a zinc-finger like structure that is involved in GAGA-motif recognition. Here, we report the formation of stabile homodimers between Arabidopsis thaliana group I member BPC1 or between group II member BPC6 in SDS-PAGE. Serial mutations of the highly conserved five Cysteines in the BPC domain of Arabidopsis thaliana BPC1 were tested for their capacity to bind to GAGA-motifs by DPI-ELISA. Our results do not support the idea of a direct involvement of these residues in making physical contact with the DNA, e.g. by formation of a zinc-finger structure. Instead, the data implies an indispensable function for the five Cysteines in homodimerization and stabilization of the protein structure by disulfide bonds. Accordingly, protein folding and structure prediction suggests the formation of a scaffold for dimerization that is supported by three intermolecular and one intramolecular S-S bond. The high degree of conservation between the BPC domains from the different groups and from different species denotes that this role for the five Cysteines might be evolutionary retained.