Standardization and Evaluation of an Anti-ZIKV IgM ELISA Assay for the Serological Diagnosis of Zika Virus Infection
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Here, we describe the development of the in-house anti-Zika virus (ZIKV) IgM antibody capture ELISA (in-house ZIKV IgM ELISA) for the detection and diagnosis of acute ZIKV infections. We compared the in-house ZIKV IgM ELISA assay performance against two commercial kits, Euroimmun ZIKV IgM and InBios 2.0 ZIKV IgM ELISA. We tested the assays’ ability to detect anti-ZIKV IgM using a well-defined serum sample panel.
This panel included 80 ZIKV negative samples (20 negative, 20 found to be primary dengue virus [DENV][ infections, 20 secondary DENV infections, and 20 Japanese encephalitis virus [JEV] infections) and 67 ZIKV reverse transcriptase-polymerase chain reaction-positive acute serum samples.
The OD values were calculated to US Energy Information Administration units by comparing them to weak positive controls. The results demonstrated the high sensitivity (88.06%) and specificity (90.00%) of our in-house ZIKV IgM ELISA and its 89.12% overall percentage agreement.
The kappa values were deemed to be within excellent range and comparable to the InBios ZIKV IgM ELISA. Some cross-reactivity was observed among secondary DENV and JEV samples, and to a much lower extent, among primary DENV samples. These data indicate that our in-house ZIKV IgM ELISA is a reliable assay for the detection of anti-ZIKV IgM antibodies in serum.
This is the first study on the prevalence of vector-borne zoonotic pathogens found in Rattus norvegicus (R. norvegicus) in urban areas of Tehran, Iran. Serological tests were used to detect IgG antibodies against Coxiella burnetii (C. burnetii) and Rickettsia spp. using a commercial qualitative rat ELISA kit. The frequency of Streptobacillus moniliformis (S. moniliformis) and Bartonella spp. was determined using a conventional PCR method.
Molecular detection and characterization of Leptospira spp. were conducted using TaqMan real-time PCR based on lipL32 gene and SecY typing methods. A total of 100 R. norvegicus rats were collected from five regions in Tehran, Iran, and investigated to determine their zoonotic pathogens. S. moniliformis and Bartonella spp. were detected in 23 of 100 (23%) and 17 of 100 (17%) R. norvegicus populations, respectively.
The highest prevalence of S. moniliformis and Bartonella spp. with similar frequency rates (n = 6/20; 30%) was seen among the R. norvegicus rats captured from the northern and southern parts of Tehran, respectively. Seroreactivity against C. burnetii and Rickettsia spp. was detected in 4% and 1% of R. norvegicus, respectively. C. burnetii. was identified only in one rat captured from the eastern part of Tehran.
Results showed that Leptospira spp. was detected only in two rats, collected from the southern part (n = 2/20; 10%) of Tehran. The secY typing method identified two different Leptospira species including L. interrogans and L. kirschneri. The results showed that urban rats might play an important role in transmission of zoonotic pathogens to humans.
The pandemic of COVID-19 has caused enormous fatalities worldwide. Serological assays are important for detection of asymptomatic or mild cases of COVID-19, and sero-prevalence and vaccine efficacy studies. Here, we evaluated and compared the performance of seven commercially available enzyme-linked immunosorbent assay (ELISA)s for detection of anti-severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) immunoglobulin G (IgG).
The ELISAs were evaluated with a characterized panel of 100 serum samples from qRT-PCR confirmed COVID-19 patients, collected 14 days post onset disease, 100 SARS-CoV-2 negative samples and compared the results with that of neutralization assay.
Results were analysed by creating the receiver operating characteristic curve of all the assays in reference to the neutralization assay. All kits, were found to be suitable for detection of IgG against SARS-CoV-2 with high accuracy. The DiaPro COVID-19 IgG ELISA showed the highest sensitivity (98%) among the kits.
The assays demonstrated high sensitivity and specificity in detecting the IgG antibodies against SARS-CoV-2. However, the presence of IgG antibodies does not always correspond to neutralizing antibodies. Due to their good accuracy indices, these assays can also aid in tracing mild infections, in cohort studies and in pre-vaccine evaluations.
This study assessed the levels of tumor necrosis factor-α (TNF-α), prostaglandin E2 (PGE2), receptor activator of nuclear factor kappa B (RANK), RANK ligand (RANKL), osteoprotegerin (OPG), and levels of Fusobacterium nucleatum, Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, Prevotella intermedia, and Streptococcus oralis in areas where airborne particle-abraded, large-grit, acid-etched (SLA), fluorine-modified, and anodized implant surfaces are used.
A total of 71 implants from 37 patients were assessed, grouped according to the surface characteristics of the implants: SLA surface (Group 1), fluorine-modified surface (Group 2), and anodized surface (Group 3). The following clinical indices were measured: Gingival Index (GI), probing depth (PD), bleeding on probing (BOP), clinical attachment level (CAL), and keratinized tissue width (KTW). Peri-implant sulcus fluid and subgingival plaque samples were also collected.
Commercial enzyme-linked immunosorbent assay (ELISA) kits were purchased for measuring TNF-α, PGE2, RANKL, RANK, and OPG. Real-time quantitative polymerase chain reaction (PCR) was used to detect P intermedia, T forsythia, T denticola, F nucleatum, P gingivalis, and S oralis levels in the subgingival biofilms. The groups showed no statistically significant differences in GI, PD, BOP, CAL, KTW, or peri-implant status.
The total amounts of PGE2, TNF-α, RANKL, RANK, and OPG and the RANKL/OPG ratio were not significantly different between groups. F nucleatum, T forsythia, P intermedia, P gingivalis, and T denticola were significantly higher in Group 3 implants. DNA concentrations of S oralis were higher in Group 2. Within the limitations of this study, SLA and fluorine-modified implant surfaces may be more clinically successful than anodized-surface implants.
Fumonisin B (FB) and other fumonisins, deoxynivalenol (DON), and zearalenone (ZEN) are mycotoxins (secondary metabolites of fungi) present at high levels of contamination in poultry diets and threatening the sustainability of the poultry industry and egg safety for consumers.
However, residual mycotoxins in breeder eggs and their effects on chicken progeny and gizzard ulcerations remain unclear. To unveil mycotoxin contaminations from daily diets to breeder eggs, 293 poultry feed samples were collected from three large-scale poultry provinces across Northern China to Southern China.
Average levels of 1,628 ± 4.36 μg/kg of FB1, 593 ± 11.16 μg/kg of DON, 69 ± 9.21 μg/kg of ZEN, 52 ± 7.33 μg/kg of OTA, and 24 ± 5.85 μg/kg of AFB1 were found in feedstuffs and poultry diets using commercial ELISA kits. In terms of residual mycotoxins in breeder eggs, FB1 and DON contaminations dominated residues in egg albumen and yolk samples.
Out of 221 breeder eggs, the average residual of FB1 in albumen were 320.6 ± 10.12 μg/kg (Hebei), 420.2 ± 10.98 μg/kg (Guangdong), and 549.4 ± 10.27 (Guangxi). Moreover, higher residual of DONs were determined in Guangdong and Guangxi provinces compared to Hebei province. ZEN, ochratoxins A (OTA), and aflatoxin B1 (AFB1) contamination at low levels were found in the above samples collected from afronmentioned three provinces.
Based on residual mycotoxins in breeder eggs, SPF embryonated eggs aged 11 days were inoculated into albumen with different doses of FB1, FB2 or DON, or a combination of FB1 and DON, or a combination of FB1 with FB2 and FB3. A lower hatching rate was observed in the chicken progenies with the combination of 24 μg of FB1 and 0.1 μg of DON compared to other treatments.
Moreover, typical gizzard ulcerations with hemorrhagic lungs were observed in the progeny of breeder eggs post-inoculation of 24 μg of FB1 and synergetic inoculation of FB1 and DON. Finally, residual FB mycotoxins were detected in the gizzards and in the lungs of the progenies.
Based on the above evidence, feed-borne FB1 and DON are dominant mycotoxins in breeder eggs and threatening food security using breeder eggs as a Trojan horse. More importantly, the residual of FB1 alone and in combination with of DON contamination are associated with low hatching rate and gizzard ulcerations in chicken progenies, hampering sustainable development perspectives of the poultry industry.