scholarly journals Serological diagnostic kit of SARS-CoV-2 antibodies using CHO-expressed full-length SARS-CoV-2 S1 proteins

2020 ◽  
Author(s):  
Rongqing Zhao ◽  
Maohua Li ◽  
Hao Song ◽  
Jianxin Chen ◽  
Wenlin Ren ◽  
...  
Keyword(s):  
Elisa Test ◽  
Full Length ◽  
Elisa Kit ◽  
His Tag ◽  
Test Kit ◽  
Human Sera ◽  
Normal Human ◽  
Development And Validation ◽  
Acid Test

WHO has declared COVID-19 a pandemic with more than 300,000 confirmed cases and more than 14,000 deaths. There is urgent need for accurate and rapid diagnostic kits. Here we report the development and validation of a COVID-19/SARS-CoV-2 S1 serology ELISA kit for the detection of total anti-virus antibody (IgG+IgM) titers in sera from either the general population or patients suspected to be infected. For indirect ELISA, CHO-expressed recombinant full length SARS-CoV-2-S1 protein with 6* His tag was used as the coating antigen to capture the SARS-CoV-2-S1 antibodies specifically. The specificity of the ELISA kit was determined to be 97.5%, as examined against total 412 normal human sera including 257 samples collected prior to the outbreak and 155 collected during the outbreak. The sensitivity of the ELISA kit was determined to be 97.5% by testing against 69 samples from hospitalized and/or recovered COVID-19 patients. The overall accuracy rate reached 97.3%. Most importantly, in one case study, the ELISA test kit was able to identify an infected person who had previously been quarantined for 14 days after coming into contact with a confirmed COVID-19 patient, and discharged after testing negative twice by nucleic acid test. With the assays developed here, we can screen millions of medical staffs in the hospitals and people in residential complex, schools, public transportations, and business parks in the epidemic centers of the outbreaks to fish out the “innocent viral spreaders”, and help to stop the further spreading of the virus.

Evaluation of a saliva test kit for feline leukemia virus antigen

1996 ◽  
Vol 32 (5) ◽  
pp. 397-400
Author(s):  
SD Babyak ◽  
MG Groves ◽  
DS Dimski ◽  
J Taboada
Keyword(s):  
Leukemia Virus ◽  
Virus Antigen ◽  
Elisa Test ◽  
Feline Leukemia Virus ◽  
Enzyme Linked Immunosorbent Assay ◽  
Elisa Kit ◽  
Test Kit ◽  
Blood Smears ◽  
Indirect Immunofluorescent ◽  
Saliva Test

An enzyme-linked immunosorbent assay (ELISA) test kit for the detection of feline leukemia virus (FeLV) antigen in saliva was evaluated in 150 cats. Saliva and blood samples from all cats were tested for FeLV using the saliva ELISA kit and a plasma ELISA kit, respectively. These results were compared with indirect immunofluorescent antibody (IFA) testing of blood smears also obtained from each cat. The proportion of cats that tested positive were 10%, 7%, and 8% for each test, respectively. Using the IFA test as the gold standard, the saliva FeLV test had a sensitivity of 91.7% and specificity of 97.1%, while the plasma ELISA test had a sensitivity of 91.7% and specificity of 100%.

scholarly journals The rapid detection of E. coli 0157 Antigen in meat products by using ELISA Test Kit

2011 ◽  
Vol 35 (2) ◽  
pp. 61-65
Author(s):  
Maithem Ihsan Abdulrasool
Keyword(s):  
Rapid Detection ◽  
Meat Products ◽  
Storage Conditions ◽  
Elisa Test ◽  
E Coli ◽  
Elisa Kit ◽  
Beef Meat ◽  
Consumer Safety ◽  
Test Kit ◽  
Beef Burger

This study was conducted for rapid detection of contamination of meat products with E. coli 0157 by usage of ELISA test kit as one of the most rapid and newest test. The study showed the efficiency of ELISA test kit used in this study in detection of bacteria antigen in meat products samples of raw beef meat , kabab and beef burger which subjected to improper storage conditions or undercooked and hence when some peoples uptake some of these products they suffered from clinical intoxication signs like diarrhea ,vomiting and hyperthermia. The kit showed the presence of (9) samples positive among (90) samples ; (2) positive out of (30) kabab samples,(3) positive out of (30) beef burger and (4) positive out of (30) raw beef meat after 16 hrs of enrichment of all samples in EC Modified broth including Novobiocin supplement as inhibitor of other bacteria and then the liquid supernatants from all prepared samples got tested by ELISA kit used in this study and the data recovered in less than 1 hr.The study indicated the ability of using ELISA kit for detection of E. coli 0157 antigens in food stuffs and reduce the time for releasing the results in less than 24 hrs when compared with conventional culturing procedure which reuiqred more than 3 days and launch the food products for consumption with focusing on the main point here which is the protection of our consumer safety.

scholarly journals Pregnancy Diagnosis with Progesterone ELISA Kit in Farm Animals, Its Accuracy and Application

2019 ◽  
Vol 36 ◽  
pp. 111-117
Author(s):  
Sambriddhi Nepal ◽  
Deepak Subedi ◽  
Krishna Kaphle
Keyword(s):  
Corpus Luteum ◽  
First Trimester ◽  
Elisa Test ◽  
Farm Animals ◽  
Subsistence Farming ◽  
Elisa Kit ◽  
Qualitative And Quantitative ◽  
Pregnancy Diagnosis ◽  
Test Kit ◽  
Qualitative And Quantitative Study

 Pregnancy is a special condition where a female lodges one or more young ones within her uterus. It is maintained by various endocrine physiology and metabolic changes between maternal and fetal circumstances. Space dine secreted by corpus luteum increases extraordinarily throughout the pregnancy, estrogen increases rapidly during first trimester and prolonged lifespan of corpus luteum and small quantity of estrogen prevents prostaglandins pulsatic secretion. We reviewed available literature to evaluate the accuracy of progesterone ELISA test kit in pregnancy diagnosis in farm animals. We found varying accuracy in global and Nepalese context but found that this is an important tool for early pregnancy diagnosis and infertility monitoringwith high accuracy which contributes to increase economic efficiency of a farm. This kit has been used for qualitative and quantitative study of progesterone to understand the reproductive status of animals. Therefore, its use is increasing in globally and in Nepal. This kit has been used at various breeding centers, and livestock service centers of Nepal. However, wider level use is still difficult due to lack of infrastructuresand subsistence farming.

IMMUNOLOGICAL REACTIVITY OF INSULIN IN HUMAN SERUM

1966 ◽  
Vol 53 (4) ◽  
pp. 673-680 ◽  
Author(s):  
Torsten Deckert ◽  
Kai R. Jorgensen
Keyword(s):  
Normal Subjects ◽  
The Other ◽  
Human Pancreas ◽  
Porcine Pancreas ◽  
Crystalline Insulin ◽  
Endogenous Insulin ◽  
Significant Difference ◽  
Human Sera ◽  
Normal Human ◽  
The One

ABSTRACT The purpose of this study was to investigate whether a difference could be demonstrated between crystalline insulin extracted from normal human pancreas, and crystalline insulin extracted from bovine and porcine pancreas. Using Hales & Randle's (1963) immunoassay no immunological differences could be demonstrated between human and pig insulin. On the other hand, a significant difference was found, between pig and ox insulin. An attempt was also made to determine whether an immunological difference could be demonstrated between crystalline pig insulin and crystalline human insulin from non diabetic subjects on the one hand and endogenous, circulating insulin from normal subjects, obese subjects and diabetic subjects on the other. No such difference was found. From these experiments it is concluded that endogenous insulin in normal, obese and diabetic human sera is immunologically identical with human, crystalline insulin from non diabetic subjects and crystalline pig insulin.

scholarly journals A Case Study Supporting Lack of SARS-CoV-2 Spread to a 3-Month Old Infant Through Exclusive Breastfeeding

2021 ◽  
pp. 089033442199107 ◽  
Author(s):  
Wei Liu ◽  
Yujie Liu ◽  
Zhenjun Liu ◽  
Changxin Hong ◽  
Jian Liu ◽  
...  
Keyword(s):  
Male Infant ◽  
Computed Tomography Imaging ◽  
Full Data ◽  
Laboratory Findings ◽  
Global Pandemic ◽  
Breast Pump ◽  
Acid Test ◽  
Maternal And Newborn

Introduction During the Coronavirus Disease 2019 global pandemic, maternal and newborn wellbeing has received much attention. Detailed reports of infected women breastfeeding their infants are uncommon. Due to incomplete information available, full data about those infants’ outcomes are lacking, and evidence of infectivity through breastfeeding has not been documented. Main Issue Here, we report about a mother who breastfed her infant until she was confirmed with the SARS-Cov-2 infection. After follow-up, we have confirmed that the infant, who was breastfed by the infected mother, was not infected. Methods A 33-year-old woman gave birth to a full-term male infant on November 8, 2019. Since birth, she had been exclusively breastfeeding the baby until she was confirmed with the SARS-Cov-2 infection on February 8, 2020. She was hospitalized, isolated from her baby, and stopped breastfeeding. Even though she remained asymptomatic, her milk was expressed using a breast pump and discarded. The mother’s milk sample was collected on February 9, 2020, and the result of the nucleic acid test for COVID-19 was negative. Her infant was asymptomatic and remained virus negative. Her laboratory findings and chest Computed Tomography imaging was normal. She was treated according to the national protocol with aerosolized interferon α2β, lopinavir/ritonavir and ribavirin. Her serum SARS-CoV-2 specific antibodies(IgG and IgM) tested positive when discharged. She returned to breastfeeding after discharge. Conclusion Our findings suggest that breastfeeding may be less of a risk than anticipated. Additional research is needed to explore this possibility.

scholarly journals Heat Inactivation of Different Types of SARS-CoV-2 Samples: What Protocols for Biosafety, Molecular Detection and Serological Diagnostics?

Viruses ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 735 ◽  
Author(s):  
Boris Pastorino ◽  
Franck Touret ◽  
Magali Gilles ◽  
Xavier de Lamballerie ◽  
Remi N. Charrel
Keyword(s):  
Infected Cell ◽  
Limit Of Detection ◽  
Elisa Test ◽  
Cell Culture Supernatant ◽  
Heat Inactivation ◽  
Standard Precautions ◽  
Viral Loads ◽  
Human Sera ◽  
European Norm ◽  
C 30

Standard precautions to minimize the risk of SARS-CoV-2 transmission implies that infected cell cultures and clinical specimens may undergo some sort of inactivation to reduce or abolish infectivity. We evaluated three heat inactivation protocols (56 °C-30 min, 60 °C-60 min and 92 °C-15 min) on SARS-CoV-2 using (i) infected cell culture supernatant, (ii) virus-spiked human sera (iii) and nasopharyngeal samples according to the recommendations of the European norm NF EN 14476-A2. Regardless of the protocol and the type of samples, a 4 Log10 TCID50 reduction was observed. However, samples containing viral loads > 6 Log10 TCID50 were still infectious after 56 °C-30 min and 60 °C-60 min, although infectivity was < 10 TCID50. The protocols 56 °C-30 min and 60 °C-60 min had little influence on the RNA copies detection, whereas 92 °C-15 min drastically reduced the limit of detection, which suggests that this protocol should be avoided for inactivation ahead of molecular diagnostics. Lastly, 56 °C-30 min treatment of serum specimens had a negligible influence on the results of IgG detection using a commercial ELISA test, whereas a drastic decrease in neutralizing titers was observed.

scholarly journals HIV and Hepatitis B seroprevalence among the nepalese blood donors

2013 ◽  
Vol 3 (5) ◽  
pp. 390-393 ◽  
Author(s):  
SR Kandel ◽  
P Ghimire ◽  
BR Tiwari ◽  
M Rajkarnikar
Keyword(s):  
Hepatitis B ◽  
Blood Donors ◽  
Hepatitis B Surface Antigen ◽  
Elisa Test ◽  
Age Group ◽  
Male And Female ◽  
Test Kit ◽  
The Difference ◽  
Donated Blood ◽  
Donor Recruitment

Background: HIV and Hepatitis B infections are public health problems in Nepal. This study was conducted based at NRCS/CBTS, with the objective of determining the HIV and HBsAg sero-prevalence in non-remunerated volunteer blood donors. Materials and Methods: A total of 66,904 units of blood collected, following donor recruitment criteriaduring March 2009-Sept. 2010 was included for analysis. All donated blood samples were subjected to screening for Transfusion transmitted infections including HIV and Hepatitis B surface antigen using standard ELISA test kits (Dade Behring, Germany). Initial reactive sera were re-tested for reconfi rmation with same test kits plus another test kit (Detect-HIV, Adaltis Inc, and Qualisa). Results: Out of 66,904 units of blood collected, 56,973 units were from male and 9,931 were from female donors. Among the total screened samples, 73 (0.10%) were found to be positive for HIV, {0.11% (64/56973) in male and 0.09% (9/9931) in female}; the difference between male and female donors (?2<3.841) was statistically signifi cant. The seroprevalence of HIV was highest in age group of 30- 39 both in male and female (p<0.001). Similarly, for HBsAg, overall seroprevalence was found to be 0.47% (316/66904 {0.42% (242/56973) in male and 0.74% (74/9931) in female}. The difference was statistically signifi cant (?2<3.841). The highest HBsAg sero-prevalence(0.65%) was also observed in same age group i.e. 30-39 (p<0.001) in male but highest seroprevalence (2.63%) was observed inage group of ?50 in female. Conclusion: Both HIV and HBV sero-prevalence is high in adult voluntary blood donors. Journal of Pathology of Nepal (2013) Vol. 3, No.1, Issue 5, 390-393 DOI: http://dx.doi.org/10.3126/jpn.v3i5.7864

Antibody-like Activity to the 2,4-Dinitrophenyl Group in Normal Human Sera

Nature ◽  
1969 ◽  
Vol 221 (5184) ◽  
pp. 960-962 ◽  
Author(s):  
MICHAEL W. BRANDRISS
Keyword(s):  
Human Sera ◽  
Normal Human

scholarly journals Recombinant MAG1 Protein of Toxoplasma gondii as a Diagnostic Antigen

2015 ◽  
Vol 64 (1) ◽  
pp. 55-59 ◽  
Author(s):  
JUSTYNA M. GATKOWSKA ◽  
BOŻENA DZIADEK ◽  
JAROSŁAW DZIADEK ◽  
KATARZYNA DZITKO ◽  
HENRYKA DŁUGOŃSKA
Keyword(s):  
Toxoplasma Gondii ◽  
Full Length ◽  
Specific Marker ◽  
Igg Antibodies ◽  
Diagnostic Antigen ◽  
Human Sera ◽  
Diagnostic Usefulness ◽  
Native Antigen

The aim of this study was to evaluate the potential diagnostic usefulness of the full-length recombinant Toxoplasma gondii MAG1 protein by determining the levels of specific IgM and IgG antibodies in mouse and human sera obtained from individuals with acute and chronic toxoplasmosis. The obtained results revealed that IgG antibodies against MAG1 are a sensitive and specific marker of T. gondii infection since the protein was recognized by both mouse and human sera, 100% and 94.3%, respectively, rendering the full-length rMAG1 a prospective alternative for the polyvalent native antigen (TLA).

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