scholarly journals Serovar prevalence of Leptospira in semirural India and the development of an IgM-based indirect ELISA

2017 ◽  
Vol 11 (03) ◽  
pp. 234-241 ◽  
Author(s):  
Sara Chandy ◽  
Lokeshwaran Kirubanandhan ◽  
Priya Hemavathy ◽  
Anees Mohammad Khadeeja ◽  
Siby Jacob Kurian ◽  
...  
Keyword(s):  
Tamil Nadu ◽  
Polymerase Chain Reaction Amplification ◽  
Public Health Problem ◽  
Cloning And Expression ◽  
Enzyme Linked Immunosorbent Assay ◽  
Major Public Health Problem ◽  
Diagnostic Systems ◽  
Serum Samples ◽  
Specificity And Sensitivity ◽  
Leptospira Serovars

Introduction: Leptospirosis is a major public health problem in India. However, it has been underreported and under-diagnosed due to a lack of awareness of the disease, a functional surveillance system, and appropriate laboratory diagnostic facilities. Methodology: This multicenter study aimed to understand the Leptospira serovars causing leptospirosis in seven secondary-level hospitals in six states in India. Since early and accurate diagnosis of leptospirosis is one of the challenges faced by clinicians in India due to the poor specificity and sensitivity of commercially available diagnostic systems, an in-house indirect enzyme-linked immunosorbent assay (ELISA) was developed. Genomic DNA from L. interrogans serovar Canicola was used for polymerase chain reaction amplification, cloning, and expression of the lipL32 gene in E. coli to amplify, clone, and express the lipL32 gene. Results: Australis was the common serovar seen at all the study centers. Serovar Icterohaemorrhagiae was seen in samples from Tamil Nadu and Assam. In-house ELISA was standardized using the purified recombinant LipL32 polypeptide and was used to evaluate serum. Subsequently, acute serum samples from leptospirosis patients (n = 60) were screened. Compared to the gold standard, the microscopic agglutination test, sensitivity and specificity of the in-house ELISA was 95% and 90%, respectively. Conclusions: Understanding Leptospira serovars circulating in leptospirosis-endemic areas will help to formulate better vaccines. LipL32-based ELISA may serve as a valuable tool for early diagnosis of leptospirosis.

scholarly journals Comparative Study of the Accuracy of Different Techniques for the Laboratory Diagnosis of Schistosomiasis Mansoni in Areas of Low Endemicity in Barra Mansa City, Rio de Janeiro State, Brazil

2015 ◽  
Vol 2015 ◽  
pp. 1-16 ◽  
Author(s):  
Maria Cristina Carvalho Espírito-Santo ◽  
Mónica Viviana Alvarado-Mora ◽  
Pedro Luiz Silva Pinto ◽  
Maria Carmen Arroyo Sanchez ◽  
Emmanuel Dias-Neto ◽  
...  
Keyword(s):  
Public Health Problem ◽  
Laboratory Diagnosis ◽  
Epidemiological Survey ◽  
Enzyme Linked Immunosorbent Assay ◽  
Major Public Health Problem ◽  
Serum Samples ◽  
Current Standard ◽  
Helminth Infections ◽  
Indirect Immunofluorescence Technique ◽  
Precipitin Test

Schistosomiasis constitutes a major public health problem, with an estimated 200 million people infected worldwide. Many areas of Brazil show low endemicity of schistosomiasis, and the current standard parasitological techniques are not sufficiently sensitive to detect the low-level helminth infections common in areas of low endemicity (ALEs). This study compared the Kato-Katz (KK); Hoffman, Pons, and Janer (HH); enzyme-linked immunosorbent assay- (ELISA-) IgG and ELISA-IgM; indirect immunofluorescence technique (IFT-IgM); and qPCR techniques for schistosomiasis detection in serum and fecal samples, using the circumoval precipitin test (COPT) as reference. An epidemiological survey was conducted in a randomized sample of residents from five neighborhoods of Barra Mansa, RJ, with 610 fecal and 612 serum samples. ELISA-IgM (21.4%) showed the highest positivity and HH and KK techniques were the least sensitive (0.8%). All techniques except qPCR-serum showed high accuracy (82–95.5%), differed significantly from COPT in positivityP<0.05, and showed poor agreement with COPT. Medium agreement was seen with ELISA-IgG (Kappa = 0.377) and IFA (Kappa = 0.347). Parasitological techniques showed much lower positivity rates than those by other techniques. We suggest the possibility of using a combination of laboratory tools for the diagnosis of schistosomiasis in ALEs.

scholarly journals Development of Recombinant Nucleoprotein-Based Diagnostic Systems for Lassa Fever

2007 ◽  
Vol 14 (9) ◽  
pp. 1182-1189 ◽  
Author(s):  
Masayuki Saijo ◽  
Marie-Claude Georges-Courbot ◽  
Philippe Marianneau ◽  
Victor Romanowski ◽  
Shuetsu Fukushi ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Hela Cells ◽  
Recombinant Baculovirus ◽  
Lassa Fever ◽  
Rabbit Serum ◽  
Enzyme Linked Immunosorbent Assay ◽  
Lassa Virus ◽  
Diagnostic Systems ◽  
Serum Samples ◽  
Capture Elisa

ABSTRACT Diagnostic systems for Lassa fever (LF), a viral hemorrhagic fever caused by Lassa virus (LASV), such as enzyme immunoassays for the detection of LASV antibodies and LASV antigens, were developed using the recombinant nucleoprotein (rNP) of LASV (LASV-rNP). The LASV-rNP was expressed in a recombinant baculovirus system. LASV-rNP was used as an antigen in the detection of LASV-antibodies and as an immunogen for the production of monoclonal antibodies. The LASV-rNP was also expressed in HeLa cells by transfection with the expression vector encoding cDNA of the LASV-NP gene. An immunoglobulin G enzyme-linked immunosorbent assay (ELISA) using LASV-rNP and an indirect immunofluorescence assay using LASV-rNP-expressing HeLa cells were confirmed to have high sensitivity and specificity in the detection of LASV-antibodies. A novel monoclonal antibody to LASV-rNP, monoclonal antibody 4A5, was established. A sandwich antigen capture (Ag-capture) ELISA using the monoclonal antibody and an anti-LASV-rNP rabbit serum as capture and detection antibodies, respectively, was then developed. Authentic LASV nucleoprotein in serum samples collected from hamsters experimentally infected with LASV was detected by the Ag-capture ELISA. The Ag-capture ELISA specifically detected LASV-rNP but not the rNPs of lymphocytic choriomeningitis virus or Junin virus. The sensitivity of the Ag-capture ELISA in detecting LASV antigens was comparable to that of reverse transcription-PCR in detecting LASV RNA. These LASV rNP-based diagnostics were confirmed to be useful in the diagnosis of LF even in institutes without a high containment laboratory, since the antigens can be prepared without manipulation of the infectious viruses.

scholarly journals An enzyme-linked immunosorbent assay for the detection of IgG antibodies against Babesia equi in horses

2004 ◽  
Vol 34 (5) ◽  
pp. 1525-1529 ◽  
Author(s):  
Cristiane Divan Baldani ◽  
Rosangela Zacarias Machado ◽  
Paulo de Tarso Landgraf Botteon ◽  
Felipe Santoro Takakura ◽  
Carlos Luiz Massard
Keyword(s):  
Immunosorbent Assay ◽  
Serological Test ◽  
Epidemiological Studies ◽  
Sao Paulo ◽  
Enzyme Linked Immunosorbent Assay ◽  
São Paulo ◽  
Igg Antibodies ◽  
Serum Samples ◽  
Babesia Equi ◽  
Specificity And Sensitivity

A crude antigenic preparation of Babesia equi was used to develop and establish the suitability of an enzyme-linked immunosorbent assay (ELISA) for the detection of parasite carriers. Optimal dilutions of the antigen, using positive and negative reference sera, were determined by checkboard titrations. The specificity and sensitivity of the ELISA were 100 %. A total of 90 serum samples were taken from horses from the Northeast region of São Paulo State and examined for diagnosis of equine B. equi infection by ELISA. Approximately 75% (n=67) of all the horses tested were found serologically positive for B. equi. These results suggest that the ELISA described may prove to be an appropriate serological test for epidemiological studies on B. equi infections in the field and that equine piroplasmosis is a cause for serious concern in the State of São Paulo, Brazil.

Correlation of serostatus and viraemia levels among Indian dengue patients at the time of first diagnosis

2020 ◽  
Vol 114 (7) ◽  
pp. 513-520
Author(s):  
Ruta Kulkarni ◽  
Shubham Shrivastava ◽  
Harshad P Patil ◽  
Divya Tiraki ◽  
Akhilesh Chandra Mishra ◽  
...  
Keyword(s):  
Public Health Problem ◽  
Vero Cells ◽  
Immunoglobulin M ◽  
Enzyme Linked Immunosorbent Assay ◽  
Serological Markers ◽  
Serum Samples ◽  
Infectious Dose ◽  
Therapeutic Monoclonal Antibodies ◽  
Tissue Culture Infectious Dose ◽  
First Diagnosis

Abstract Background Dengue is a public health problem worldwide. Therapeutic monoclonal antibodies (MAbs) against dengue virus (DENV) are likely to be available soon. In view of the feasibility issues pertaining to pretreatment viraemia quantitation for therapy decisions, we conducted this study for investigation of a correlation between patient serostatus (NS1/immunoglobulin M [IgM]/IgG) and viraemia levels among Indian dengue patients at the time of first diagnosis. Methods The study included 297 serum samples from dengue patients in Pune, India. The samples were tested for NS1, IgM and IgG (capture enzyme-linked immunosorbent assay [ELISA] for identifying secondary dengue) using Panbio ELISAs. Quantitation of viraemia was conducted using an NS1 ELISA-based 50% tissue culture infectious dose (TCID50) test in Vero cells. Results Viraemia was detectable only among NS1-positive patients (n = 229, range 0.5–8.3 logTCID50/ml) with a mean titre of 1.9 logTCID50/ml. Among the NS1-positive patients, DENV titres were higher in IgM-negative than IgM-positive patients (p &lt; 0.0001) and in primary (IgG &lt; 18 Panbio units) versus secondary (IgG &gt; 22 Panbio units) dengue patients (p = 0.002). Virus titres were higher during the first 3 days of illness and decreased later (p = 0.005). Conclusions The study provides a range of infectious DENV titres in relation to serologic status among dengue patients in India. The data suggest the possibility of using serological markers (NS1/IgM) as a basis for treatment decisions.

scholarly journals Plasmodium ovale: Parasite and Disease

2005 ◽  
Vol 18 (3) ◽  
pp. 570-581 ◽  
Author(s):  
William E. Collins ◽  
Geoffrey M. Jeffery
Keyword(s):  
Public Health Problem ◽  
Molecular Techniques ◽  
Sub Saharan Africa ◽  
Enzyme Linked Immunosorbent Assay ◽  
Developmental Cycle ◽  
Major Public Health Problem ◽  
Plasmodium Ovale ◽  
Malaria Parasites ◽  
Sub Saharan

SUMMARY Humans are infected by four recognized species of malaria parasites. The last of these to be recognized and described is Plasmodium ovale. Like the other malaria parasites of primates, this parasite is only transmitted via the bites of infected Anopheles mosquitoes. The prepatent period in the human ranges from 12 to 20 days. Some forms in the liver have delayed development, and relapse may occur after periods of up to 4 years after infection. The developmental cycle in the blood lasts approximately 49 h. An examination of records from induced infections indicated that there were an average of 10.3 fever episodes of ≥101°F and 4.5 fever episodes of ≥104°F. Mean maximum parasite levels were 6,944/μl for sporozoite-induced infections and 7,310/μl for trophozoite-induced infections. Exoerythrocytic stages have been demonstrated in the liver of humans, chimpanzees, and Saimiri monkeys following injection of sporozoites. Many different Anopheles species have been shown to be susceptible to infection with P. ovale, including A. gambiae, A. atroparvus, A. dirus, A. freeborni, A. albimanus, A. quadrimaculatus, A. stephensi, A. maculatus, A. subpictus, and A. farauti. An enzyme-linked immunosorbent assay has been developed to detect mosquitoes infected with P. ovale using a monoclonal antibody directed against the circumsporozoite protein. Plasmodium ovale is primarily distributed throughout sub-Saharan Africa. It has also been reported from numerous islands in the western Pacific. In more recent years, there have been reports of its distribution on the Asian mainland. Whether or not it will become a major public health problem there remains to be seen. The diagnosis of P. ovale is based primarily on the characteristics of the blood stages and its differentiation from P. vivax. The sometimes elliptical shape of the infected erythrocyte is often diagnostic when combined with other, subtler differences in morphology. The advent of molecular techniques, primarily PCR, has made diagnostic confirmation possible. The development of techniques for the long-term frozen preservation of malaria parasites has allowed the development diagnostic reference standards for P. ovale. Infections in chimpanzees are used to provide reference and diagnostic material for serologic and molecular studies because this parasite has not been shown to develop in other nonhuman primates, nor has it adapted to in vitro culture. There is no evidence to suggest that P. ovale is closely related phylogenetically to any other of the primate malaria parasites that have been examined.

scholarly journals Serological and Molecular Study of Dengue Viruses in Different Hospitals of Nepal

2013 ◽  
Vol 2 (1) ◽  
pp. 20-25 ◽  
Author(s):  
GP Gupta ◽  
Y Shah ◽  
A Poudel ◽  
R Pun ◽  
KP Pant ◽  
...  
Keyword(s):  
Dengue Virus ◽  
Public Health Problem ◽  
Enzyme Linked Immunosorbent Assay ◽  
Age Group ◽  
Serum Samples ◽  
Important Public Health Problem ◽  
Monsoon Period ◽  
Occupation Group ◽  
Hilly Region ◽  
Acute Patients

Background: Dengue Virus (DV) is an emerging mosquito borne viral disease and important public health problem in low land of Terai region which is also expanding to hilly region. Methods: This study was designed to estimate sero-prevalence of dengue virus infection in the post monsoon period (Jun-Dec) of 2010 in Nepalese patients with fever visiting hospitals of Birganj, Damouli, Biratnagar and Dhading Besi. Serum samples were collected from 280 patients visiting hospitals with history of fever & clinically suspected dengue fever. The sero-prevalence of dengue virus specific IgM was determined by enzyme linked immunosorbent assay (ELISA) kit (SD, Korea) Results: The anti-dengue IgM positivity was found to be 8.2%. The positive dengue cases were higher in male (10.5%) as compared to female (6.5%). Among different age groups, the highest positive cases (11.5 %) were from age group below 15 years followed by above 50 years age group with 8.5%. Out of 4 hospitals, the highest positive cases were in Tanahu District Hospital, Damouli (23.8%) followed by Koshi Zonal Hospital, Biratnagar (12.5%). Age and gender were found to be independent predictors. The highest numbers of dengue positive cases were in occupation group business (13.3%) followed by agriculture (11.5%). Conclusion: The dengue positivity was estimated in acute patients from different hospitals of Nepal by enzyme immunoassay and reverse transcriptase polymerase chain reaction. Therefore, the serological marker can be used to diagnose the acute patients of dengue during outbreaks. Nepal Journal of Medical Sciences | Volume 02 | Number 01 | Jan-Jun 2013 | Page 20-25 DOI: http://dx.doi.org/10.3126/njms.v2i1.7646

scholarly journals Cysticercus antibodies and antigens in serum from blood donors from Pondicherry, India

2005 ◽  
Vol 47 (4) ◽  
pp. 227-230 ◽  
Author(s):  
Subhash Chandra Parija ◽  
N. Balamurungan ◽  
Priyadarshi Soumyaranjan Sahu ◽  
S.P. Subbaiah
Keyword(s):  
Immunosorbent Assay ◽  
Tamil Nadu ◽  
Blood Donors ◽  
Enzyme Linked Immunosorbent Assay ◽  
Antibody Testing ◽  
Specific Detection ◽  
Serum Samples ◽  
Blood Samples ◽  
Tamil Nadu State ◽  
Apparently Healthy

The aim of the present study was to screen the serum of blood donors, which are apparently healthy and residing in Pondicherry or its neighboring districts of Tamil Nadu State, for specific detection of Cysticercus antigens and antibodies. A total of 216 blood samples were collected from blood donors at the Central Blood Bank, JIPMER Hospital, Pondicherry, India during January and February 2004. Enzyme-linked immunosorbent assay (ELISA) was used to demonstrate anti-Cysticercus antibodies and the Co-agglutination (CoA) was used to detect antigen in sera. 14 (6.48 %) males were positive for either anti-Cysticercus antibodies or antigens. Of these eight sera were positive for anti-Cysticercus antibodies and six were positive for antigens. Results of the present study show that serum Cysticercus antigen detection may be a useful adjunct to antibody testing for seroprevalence studies of cysticercosis in the community. The present study is the first kind of study, carried out to determine both cysticercal antibodies as well as antigens in the serum samples collected from the healthy blood donors.

Development and preliminary application of gE enzyme-linked immunosorbent assay for detection of the antibody to gE protein ofPseudorabies virusin pigs

2005 ◽  
Vol 2 (2) ◽  
pp. 79-83 ◽  
Author(s):  
Tang Yong ◽  
Chen Huan-Chun ◽  
Qin Ya-Li ◽  
He Qi-Gai ◽  
Jin Mei-Lli ◽  
...  
Keyword(s):  
Immunosorbent Assay ◽  
Pseudorabies Virus ◽  
Enzyme Linked Immunosorbent Assay ◽  
Diagnostic Specificity ◽  
Serum Samples ◽  
Agreement Rate ◽  
Glycoprotein E ◽  
Recombinant Glycoprotein ◽  
Specificity And Sensitivity ◽  
Preliminary Application

AbstractTo differentiate pigs infected withPseudorabies virus(PrV) from pigs vaccinated with gE-PrV, a glycoprotein E enzyme-linked immunosorbent assay (gE-ELISA) based on recombinant glycoprotein E (gE) (which was expressed byEscherichia coli, purified, denatured and renatured) was developed. By testing 115 serum samples, the diagnostic specificity and sensitivity of the developed gE-ELISA were evaluated to be 94.5% and 96.7%, respectively. Five serum samples were tested with plates from five lots, and the results had a coefficient of variation of less than 10%, showing good reproducibility of gE-ELISA. This gE-ELISA was compared with a commercial blocking ELISA by testing 356 serum samples. The agreement rate of the two assays was 92.13% (328/356). These results suggested that the gE-ELISA developed in our laboratory could be used in differentiating PrV-infected and gE-PrV-vaccinated pigs.

scholarly journals A Valuable Antigen Detection Method for Diagnosis of Acute Hepatitis E

2014 ◽  
Vol 53 (3) ◽  
pp. 782-788 ◽  
Author(s):  
Gui-Ping Wen ◽  
Zi-Min Tang ◽  
Fan Yang ◽  
Ke Zhang ◽  
Wen-Fang Ji ◽  
...  
Keyword(s):  
Acute Hepatitis ◽  
Detection Method ◽  
Public Health Problem ◽  
Hepatitis E ◽  
Antigen Detection ◽  
Enzyme Linked Immunosorbent Assay ◽  
Serum Samples ◽  
Detection Rates ◽  
Acute Hepatitis E ◽  
Capture Antibody

Hepatitis E virus (HEV) is a serious public health problem. The commonly used tests that are specific for current HEV infection diagnosis include the detection of anti-HEV IgM and HEV RNA. Here, we report an improved enzyme-linked immunosorbent assay (ELISA) method for HEV antigen detection with a linear range equivalent to 6.3 × 103to 9.2 × 105RNA copies per ml. The monoclonal antibody (MAb) 12F12, a high-ability MAb that binds HEV virus, was selected as the capture antibody from a panel of 95 MAbs. The positive period of HEV antigenemia in infected monkeys using this test was, on average, 3 weeks longer than previously reported and covered the majority of the acute phase. The positive detection rates of IgM, RNA, and new antigen from the first serum samples collected from 16 confirmed acute hepatitis E patients were 81% (13/16), 81% (13/16), and 100% (16/16), respectively. In three patients, the initial serum specimens that tested negative for IgM, despite the presence of symptoms of acute hepatitis and elevated alanine aminotransferase (ALT) levels, were positive for HEV antigen and HEV RNA. In contrast, the serum samples of the three RNA-negative patients were antigen positive (and IgM positive), possibly due to the degradation of HEV nucleic acids. Our results suggest that this new antigen detection method has acceptable concordance with RNA detection and could serve as an important tool for diagnosing acute hepatitis E.

Infrared analysis of lipoproteins in the detection of alcohol biomarkers

2017 ◽  
Vol 55 (6) ◽  
pp. 876-881 ◽  
Author(s):  
Sander De Bruyne ◽  
Tinne Monteyne ◽  
Marijn M. Speeckaert ◽  
Joris R. Delanghe
Keyword(s):  
Area Under The Curve ◽  
Public Health Problem ◽  
Ethyl Esters ◽  
High Density Lipoproteins ◽  
Infrared Analysis ◽  
Major Public Health Problem ◽  
Serum Samples ◽  
Driver's License ◽  
Carbohydrate Deficient Transferrin ◽  
Ftir Spectrometer

Abstract Background: Alcoholism is a major public health problem. Alcohol causes modifications in the composition and concentration of lipoproteins and influences the enzymes and transfer proteins that transform lipoproteins in plasma. Alcohol is associated with the presence of alcohol biomarkers (fatty acid ethyl esters [FAEEs] and phosphatidylethanol [PEth]) in lipoproteins. We explore the possibilities of detecting alcohol biomarkers in non-high-density-lipoproteins (non-HDLs) precipitated from serum using attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR). Methods: Analyzes were carried out on stored serum samples, with known % carbohydrate-deficient transferrin (CDT) values, included in a driver’s license regranting program under the control of the Belgian Institute of Road Safety. The study consisted of 127 control samples (CDT≤1.3%) and 114 alcoholic samples (CDT>1.3%). Liver enzymes, CRP, triglycerides, total, HDL- and LDL-cholesterol values were determined. Non-HDLs were precipitated with sodium phosphotungstate and MgCl2 and analyzed using ATR-FTIR in the range from 4500 cm−1 to 450 cm−1 using a Perkin Elmer ATR-FTIR Spectrometer Two. Results: The area under the curve of the 1130–990 cm−1 region (AUC1130−990 cm−1) was able to discriminate controls from alcoholics (p<0.0001) due to the presence of FAEEs in lipoproteins. Multiple regression analysis significantly predicted the AUC1130−990 cm−1 (adj. r2=0.13, p<0.0001). Significant correlations were found between AUC1130−990 cm−1 and CDT values (r=0.32, p<0.0001), AST/ALT ratio (r=0.21, p=0.001). GGT showed no significant correlation. Conclusions: Infrared analysis of lipoproteins is a potential tool in the detection of alcohol biomarkers.

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