Establishment of a Flexible Platform for an Automated Brain-Derived Neurotrophic Factor—ELISA

2007 ◽  
Vol 12 (4) ◽  
pp. 219-229
Author(s):  
Ilka Schneider ◽  
Paul Stoll ◽  
Daniel Haller ◽  
Kerstin Thurow

Enzyme-linked immunosorbent assay (ELISA) is a standard immunoassay to estimate protein concentrations in a variety of samples. An automated ELISA procedure was established that allows the measurement of the concentration of numerous proteins in a small sample volume. The automated ELISA procedure was tested by measuring the concentration of brain-derived neurotrophic factor in serum samples from humans. It was shown that the reproducibility of protein concentrations in three assay plates within one automated run was greater than 92%, within independent automated experiments greater than 96%. Automated processing with a maximum capacity of six plates and 240 serum samples per run showed an average interassay precision of 91 %. Serial dilutions of randomly chosen sera displayed significant linearity of recovered concentration. In conclusion it can be stated that the automated assay provides high flexibility with highly reproducible results and has several advantages compared to the manual method, including less operator dependence and faster sample throughput. The investigated ELISA test system seems to exhibit analytical characteristics indicating further clinical application. (JALA 2007;12:219–29)

2021 ◽  
Vol 8 ◽  
Author(s):  
Amin Riat ◽  
Abdulhadi Suwandi ◽  
Samaneh Khoshandam Ghashang ◽  
Manuela Buettner ◽  
Luqman Eljurnazi ◽  
...  

Ramadan fasting (RF) is a type of diurnal intermittent fasting. Previous studies reported the benefits of RF in healthy subjects on mood and health related to quality of life (QoL). Cortisol and brain-derived neurotrophic factor (BDNF) have been shown to play a role in mood, body composition parameters, and health-related QoL. This study aimed at elucidating the mechanism of the benefit of RF, particularly cortisol and BNDF and their association with mood and QoL. Insulin growth factor-1 (IGF-1), interleukin (IL)-8, matrix metalloproteinase (MMP)-9, and myoglobin were determined. Thirty-four healthy men and women were recruited. Serum from peripheral venous blood samples was collected at five time points: 1 week before RF (T1); mid of RF (T2), last days of RF (T3), 1 week after RF (T4), and 1 month after RF (T5). The amounts of biological mediators in the serum samples were determined by enzyme-linked immunosorbent assay (ELISA) and Luminex assays. BDNF and cortisol significantly decreased at T3 (p < 0.05) and T4 (p < 0.001) compared to T1, respectively. It seems the benefits of RF for mood-related symptoms are mediated by different biological mediators, particularly cortisol and BDNF.


2020 ◽  
Vol 10 ◽  
pp. 204512532097379
Author(s):  
Wei Zheng ◽  
Yan-Ling Zhou ◽  
Cheng-Yu Wang ◽  
Xiao-Feng Lan ◽  
Bin Zhang ◽  
...  

Background: This study is the first to examine the association between plasma levels of brain-derived neurotrophic factor (BDNF) and the antisuicidal effects of repeated ketamine infusions in depressed patients with suicidal ideation. Methods: Fifty-seven depressed patients with suicidal ideation received six ketamine infusions (0.5 mg/kg) during a 12 days period. Suicidality was measured with the Scale for Suicidal Ideations (SSI-part 1), item 10 of the Montgomery–Åsberg Depression Rating Scale (MADRS), and item 3 of the Hamilton Depression Rating Scale (HAMD) at baseline, 1 day after the first infusion (1 day), 1 day after the sixth infusion (13 days), and at 2 weeks after the last infusion (26 days). Plasma levels of BDNF were measured by enzyme-linked immunosorbent assay at baseline, 13 days, and 26 days. Results: Overall, 46 (80.7%) depressed patients with suicidal ideation had an antisuicidal response at 13 days. Despite a significant reduction in suicidal symptoms over time, no changes in plasma levels of BDNF were found after ketamine treatment when compared with baseline. Correlation analysis showed that no significant association was observed between the plasma levels of BDNF and the changes in the severity of suicidal symptoms as measured by SSI-part 1, item 10 of the MADRS, or item 3 of the HAMD at 1 day, 13 days, and 26 days (all p < 0.05). Conclusion: Our results indicated that plasma levels of BDNF may not serve as a biomarker for determining the antisuicidal effects of six ketamine infusions in depressed patients with suicidal ideation.


2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Ahmed M. Abu El-Asrar ◽  
Mohd Imtiaz Nawaz ◽  
Mohammad Mairaj Siddiquei ◽  
Abdullah S. Al-Kharashi ◽  
Dustan Kangave ◽  
...  

To test the hypothesis that brain-derived neurotrophic factor-(BDNF-) mediated neuroprotection is reduced by high-mobility group box-1 (HMGB1) in diabetic retina, paired vitreous and serum samples from 46 proliferative diabetic retinopathy and 34 nondiabetic patients were assayed for BDNF, HMGB1, soluble receptor for advanced glycation end products (sRAGE), soluble intercellular adhesion molecule-1 (sICAM-1), monocyte chemoattractant protein-1 (MCP-1), and TBARS. We also examined retinas of diabetic and HMGB1 intravitreally injected rats. The effect of the HMGB1 inhibitor glycyrrhizin on diabetes-induced changes in retinal BDNF expressions was studied. Western blot, ELISA, and TBARS assays were used. BDNF was not detected in vitreous samples. BDNF levels were significantly lower in serum samples from diabetic patients compared with nondiabetics, whereas HMGB1, sRAGE, sICAM-1, and TBARS levels were significantly higher in diabetic serum samples. MCP-1 levels did not differ significantly. There was significant inverse correlation between serum levels of BDNF and HMGB1. Diabetes and intravitreal administration of HMGB1 induced significant upregulation of the expression of HMGB1, TBARS, and cleaved caspase-3, whereas the expression of BDNF and synaptophysin was significantly downregulated in rat retinas. Glycyrrhizin significantly attenuated diabetes-induced downregulation of BDNF. Our results suggest that HMGB1-induced downregulation of BDNF might be involved in pathogenesis of diabetic retinal neurodegeneration.


2021 ◽  
Vol 83 (3) ◽  
pp. 66-71
Author(s):  
А.Y. Horlov ◽  
◽  
V.H. Serdiuk ◽  
О.K. Kiselova ◽  
A.O. Shevchuk ◽  
...  

A novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease (COVID)-19, that emerged as a major pandemic. SARS-CoV-2 was identified as a betacoronavirus. Nucleocapsid protein (NP) is evolutionary high protein homologies and solid structure protein for SARS-CoV-2 detection as opposed to other proteins, that aren`t reliable as a single viral antigen during diagnostics methods. The viral RNA can be detected from nasal and pharyngeal swabs and bronchoalveolar lavage samples by PCR assay. However, the wrong collection of samples can lead to false-negative diagnosis and have dangerous consequences at this stage of pandemic. One of efficient and accurate methodological approaches for the screening of pathogens are serological assays. Aim. Evaluation and comparison of the sensitivity of invented DIA®-SARS-CoV-2-Ag-R enzyme-linked immunosorbent assay (ELISA)-based test system and commercial rapid tests, which detect the viral antigen of SARS-CoV-2. Methods. We carried out a comparison of DIA®-SARS-CoV-2-Ag-R and existed commercial test systems, which are used to detect the antigen of SARS-CoV-2 virus. Rapid tests are intended for nasopharyngeal swabs, but we proposed a protein of our own manufacture – recombinant NP as a calibrator. The detection limit was calibrated by standard CFAR #100982 NIBSC, UK. We had determined levels of NP (1400, 900, 750, 640 and 280 pg/mL) that we used as a sample for the rapid tests. The COVID-19 Ag Rapid Tests were performed according to the manufactures instructions at room temperature. Results. DIA®-SARS-CoV-2-Ag-R detected 10 pg/mL of in-house standard of recombinant SARS-CoV-2 NP. The positive results were observed using 1400, 900, 750 pg/mL, while 640 and 280 pg/mL samples were performed as negative in ABBOTT-PanBio test. The rapid tests manufactured by МBU, BIOTIME, Core Technology, SD BIOSENSOR and Turklab showed positive results only in 1400 pg/mL concentration. NP of lower levels was detected as a negative sample. The LEPU MEDICAL test was evaluated as positive sample using 900 pg/mL. The rapid test manufactured by Green Cross Medical Science Corp. showed negative results for all levels of NP. It can mean that the sensitivity of test is lower and demands higher level of antigen to detect the presence of SARS-CoV-2. Conclusions. The study presented an excellent analytical sensitivity of DIA®-SARS-CoV-2-Ag-R against commercial Antigen rapid tests. Thus, invented ELISA test system can be recommended for widespread usage for detection and confirmation of acute stage of SARS-CoV-2 infection.


BJPsych Open ◽  
2021 ◽  
Vol 7 (2) ◽  
Author(s):  
Nanna Aagaard Petersen ◽  
Marc Østergaard Nielsen ◽  
Klara Coello ◽  
Sharleny Stanislaus ◽  
Sigurd Melbye ◽  
...  

Background Brain-derived neurotrophic factor (BDNF), which facilitates neuroplasticity and synaptogenesis, may be decreased in bipolar disorder, but has not been systematically investigated in people with newly diagnosed bipolar disorder and unaffected first-degree relatives. Aims To compare BDNF levels in patients with newly diagnosed bipolar disorder, their unaffected first-degree relatives and healthy controls. Method The study investigated plasma BDNF levels in patients (n = 371) with newly diagnosed bipolar disorder, their unaffected first-degree relatives (n = 98) and healthy controls (n = 200) using enzyme-linked immunosorbent assay. We further investigated associations between BDNF levels and illness-related variables and medication status. Results BDNF levels were found to be 22.0% (95% CI 1.107–1.343) higher in patients with bipolar disorder compared with healthy controls (P < 0.001) and 15.6% higher in unaffected first-degree relatives compared with healthy controls (95% CI 1.007–1.327, P = 0.04), when adjusting for age and gender. Further, BDNF levels were positively associated with duration of illness at a trend level (P = 0.05), age (P = 0.001) and use of anti-epileptic medication (P = 0.05). Conclusions These findings suggest that BDNF levels are not decreased in the early stages of bipolar disorder and in unaffected first-degree relatives contrasting with prior findings during later stages of the illness.


Author(s):  
Daniel Muasya ◽  
George Karuoya Gitau ◽  
Thaiyah Gitau Andrew ◽  
Daniel Waweru Gakuya ◽  
John Vanleeuwen ◽  
...  

Bovine tuberculosis (BTB) is an important zoonotic disease which has remained persistent in many areas of the World. Control and eradication has proved problematic due to the challenges in effective screening and diagnosis. Limited information on the status of BTB in Kenya presents a need to investigate its occurrence in cattle population. The study was carried out using an indirect antibody Enzyme Linked Immunosorbent Assay (ELISA-IDEXX-USA) to assess the agreement with Comparative Intradermal Tuberculin Test (CITT) test results between August and December 2013 in Laikipia County. The study also determined the apparent prevalence of cattle BTB antibodies in Laikipia County. A total of 276 bovine serum samples were tested using MPB70 and MPB83 recombinant proteins as capture antigens in the ELISA kit. Data were recorded in Microsoft Excel and exported to SPSS 16.0 for analysis. Apparent prevalence was calculated as a proportion at 95% CI, Kappa statistics computed, and test of significance assessed by Chi-square and Fisher exact test.  The results showed an individual animal apparent prevalence of 3.9% (11/276) and a herd prevalence of 58.3% (7/12). There was no significant association between BTB infection and both animal level factors, breed and sex. Kappa agreement test between ELISA test and TST showed a good agreement at K= 0.65. This study reported the prevalence of BTB in cattle for the first time in Laikipia County Kenya using the IDEXX ELISA. The ELISA test was comparable to the tuberculin test which is used as the gold standard for screening TB on live animals. The two tests can be used alongside for series or parallel interpretation to achieve desirable diagnostic sensitivity and specificity in disease control programs.


Author(s):  
Flywell Kawonga ◽  
Gerald Misinzo ◽  
Dylo Pemba ◽  
Leonard Mboera ◽  
Isaac Thom Shawa

Chikungunya is a mosquito-borne viral disease caused by Chikungunya virus (CHIKV. We conducted this study determine the seroprevalence and clinical presentation of Chikungunya infection among outpatients seeking healthcare in Mzuzu City, Malawi. Blood samples were collected from malaria negative and non-septic febrile outpatients with fevers &ge;38 &deg;C, for not more than 5 days. The enzyme- linked immunosorbent assay (ELISA) test was used to detect anti-CHIKV IgM antibodies and its results were used to determine seroprevalence of Chikungunya. A total of 119 serum samples were tested, of these, 73 (61.3%) tested positive for anti-CHIKV IgM antibodies by ELISA. Laboratory requisition forms were used to capture demographic information such as age, sex, clinical signs and symptoms presented by the enrolled patients. Age groups of 1-9, 10- 19, 20- 29, 30- 39, 40- 49, and &ge;50 years had 17.8% (n= 13), 12.3 %,( n=9), 15.1%) (n=11), 19.2%; (n=14), 17.8% (n=13) and 17.8% (n=13) proportion of seroprevalence respectively. Most of the CHIKV infected individuals presented with fever (52.05%), joint pain (45.21%) and abdominal pain (42.67%). The presence of anti- CHIKV IgM antibodies suggest the presence of recent CHIKV infection and therefore accurate laboratory assays are highly recommended for CHIKV diagnosis and appropriate management of febrile patients.


2022 ◽  
Vol 20 (6) ◽  
pp. 72-80
Author(s):  
L. N. Lukhverchyk ◽  
G. L. Alatortseva ◽  
L. N. Nesterenko ◽  
V. Y. Kabargina ◽  
V. V. Dotsenko ◽  
...  

Relevance. The introduction of Varicella vaccine prophylaxis explains the need to develop a methodology for monitoring the vaccination effectiveness and the intensity of population immunity. This problem can be solved using quantitative immunoassay methods. Aim. Development of an enzyme-linked immunosorbent assay for the concentration of class G immunoglobulins (AB) to Varicella zoster virus (VZV) determining and assessing its functional characteristics and diagnostic efficiency. Materials and methods. Recombinant antigen GE VZV. WHO International Standard for Antibodies to VZV W1044. Blood serum samples from healthy people and patients with Chickenpox and Herpes zoster, blood serum samples containing IgG antibodies to herpes simplex viruses of the first and second types, cytomegalovirus, Epstein-Barr virus. Anti-VZV ELISA (IgG) reagent kit (Euroimmun, Germany). Indirect enzyme-linked immunosorbent assay. Immunization of animals with recombinant antigen GE, isolation, and purification of specific antibodies. Conjugation of monoclonal antibodies to human IgG with antibodies to antigen GE and with horseradish peroxidase. Results. An enzyme-linked immunosorbent assay in «an indirect» format has been developed to determine the specific antibodies to VZV concentration (IU/ml) in human serum/plasma. An artificial calibrator for determining the concentration of AB-VZV had been synthesized and standardized according to the International WHO-standard W1044. The main functional characteristics of the developed enzyme-linked immunosorbent assay are determined in accordance with GOST 51352-2013. The diagnostic kit was tested on blood serum samples from children with chickenpox (n = 43), adults with Herpes zoster (n = 158), healthy individuals (n = 781). The diagnostic sensitivity of the test system was 85%, the diagnostic specificity was 87% according to the ROC analysis. The absence of cross-reactivity of the test system was shown on samples with serological markers of other herpesvirus infections (n = 94). Comparative trials of the developed test system and its commercial analog, the Anti-VZV ELISA (IgG) reagent kit, did not reveal statistically significant differences between their functional characteristics. Conclusions. The developed test system for determining of the AB-VZV concentration in human serum/plasma in terms of its functional characteristics meets the GOST requirements, is characterized by high diagnostic efficiency, can be used to monitor the effectiveness of vaccine prophylaxis and strength of population immunity, as well as to assess the immune response in chickenpox and Herpes zoster.


2020 ◽  
Vol 5 (2) ◽  
pp. 161-174
Author(s):  
Nicholas Massa ◽  
Alaaeddin Alrohaibani ◽  
Kevin Mammino ◽  
Medina Bello ◽  
Nicholas Taylor ◽  
...  

Background: Schizophrenia (SCZ) is a severe, chronic illness characterized by psychotic symptoms and impairments in many cognitive domains. Dysregulation of brain derived neurotrophic factor (BDNF) is associated with the cognitive impairments seen in patients with SCZ. Given the growing literature supporting a positive effect of aerobic exercise on cognition in other populations, we hypothesized that a structured aerobic exercise program would improve cognitive and functional outcomes in subjects with SCZ, potentially mediated by increases in BDNF. Methods: The study was a small randomized parallel group clinical trial of subjects with SCZ comparing 12 weeks of aerobic exercise (AE) against control (CON) stretching and balance training. At Baseline, Week 12, and Week 20 we collected serum samples for analysis of brain derived neurotrophic factor (BDNF), and assessed functional, physical, and cognitive outcomes. Linear regression models were used to compare change scores between timepoints. Results: We randomized 21 subjects to AE and 17 to CON; however, only 9 AE and 6 CON completed their programs. Subjects in both groups were slower at the 400 m walk in Week 12 compared to Baseline, but the AE group had significantly less slowing than the CON group (B = –28.32, p = 0.011). Between Week 12 and Week 20, the AE group had a significantly greater change score on the Composite and Visual Learning Domain of the MATRICS Consensus Cognitive Battery (B = 5.11, p = 0.03; B = 13.96, p = 0.006). Conclusion: These results indicate that participation in a structured aerobic exercise paradigm may modestly blunt physical function decline and enhance cognitive function in individuals with SCZ.


Author(s):  
Naser Nazari ◽  
Tooran Nayeri ◽  
Farkhondeh Hazrati

Background and Aims: Echinococcus granulosus (E. granulosus) is a cestode parasite that causes cystic hydatid disease in humans worldwide. Iran is one of the endemic regions for infection that indicate the importance and presence of infection in this country. Therefore, the current research aimed to characterize the seroprevalence of human cystic echinococcosis in Sanandaj city, Kurdistan province, western Iran. Materials and methods: Totally, 500 serum samples were collected from patients referred to different health centers in Sanandaj city using cluster sampling in 2018-2019. All the sera were examined using the enzyme-linked immunosorbent assay test. Results: The seroprevalence of human hydatidosis was reported at 2.2% by ELISA test in Sanandaj city. This rate was 9 (1.9%) in women and 2 (0.4) in men. The age group of 20-30 years old had the highest positivity rate (1.0%). Also, the subjects that consumed home slaughtered meat had the highest infection rate at 4 (0.8%). There was no significant difference regarding factors studied such as sex, education, residence, consumed water, keeping a dog, and the seropositivity. Conclusions: Seroprevalence of human cystic echinococcosis in Sanandaj city is lower than the general prevalence in Iran. Our research team hopes to provide accurate data on the prevalence of hydatidosis in Sanandaj encourage more extensive research to help prevent this parasite in Iran and worldwide.


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