MyMedR

Displaying publications 21 - 40 of 106 in total

Abstract:

Sort:

Detection of Mycoplasma gallisepticum antibodiesin the sera of village chickens by the enzyme-linked immunosorbent assay

Shah-Majid M

Trop Anim Health Prod, 1996 May;28(2):181-2.
PMID: 8809982
Matched MeSH terms: Enzyme-Linked Immunosorbent Assay/methods*
Fulltext The use of an in-house modified double antibody sandwich ELISA to detect Aspergillus antigens in sera of immunosuppressed patients

Samad SA, Rahman HA

Singapore Med J, 1999 Aug;40(8):513-8.
PMID: 10572490

The purpose of this study was to retrospectively detect Aspergillus antigens in sera obtained from immunocompromised host using an in-house modified double antibody sandwich ELISA.

Matched MeSH terms: Enzyme-Linked Immunosorbent Assay/methods*
Fulltext Seroprevalence of toxocariasis among Orang Asli (Indigenous people) in Malaysia using two immunoassays

Romano N, Nor Azah MO, Rahmah N, Lim Y AL, Rohela M

Trop Biomed, 2010 Dec;27(3):585-94.
PMID: 21399601 MyJurnal

Toxocariasis is a zoonotic helminthic infection of humans caused by the dog roundworm (Toxocara canis) or cat roundworm (Toxocara cati). There are two main human syndromes: visceral larva migrans (VLM), which are characterized by symptoms associated with major organs and ocular larva migrans (OLM), in which pathological effects on the host are restricted to the eye and the optic nerve. The present study evaluated the seroprevalence of toxocariasis among the Orang Asli with an IgG4-ELISA using recombinant antigens (rTES-26, rTES-30 and rTES-120) and an IgG-ELISA commercial kit (Cypress Diagnostic, Belgium). A total of 188 serum samples were analyzed using IgG4-ELISA recombinant antigens while 83 were tested using IgG-ELISA. Overall, 9 out of 188 (4.8%) samples were positive with the former assay: rTES-26 (2.7%) and rTES-30 (2.1%); and 63 out of 83 (75.9%) were positive with the IgG-ELISA. In general, the seroprevalence of toxocariasis among males (9.5%) was higher compared to females (1%). Children below 12 years (6.3%) have higher seroprevalence rate compared to adults (1.2%). Out of 59 IgG positive samples, 56 (94.9%) were also positive with soil-transmitted helminth (STH) infections which may indicate high false positivity. None of the IgG4- ELISA positive samples were positive with STH infections. Of 9 positive samples with IgG4-ELISA, 7 were also positive with IgG-ELISA giving the probability of true cases. The present finding indicated that exposure to Toxocara infection is not unusual among Malaysian aborigines, and it affects both sexes and all age groups. As a prevention strategy, more effective public health programmes to promote better understanding on the consequences of toxocariasis among the Orang Asli communities are deemed necessary.

Matched MeSH terms: Enzyme-Linked Immunosorbent Assay/methods
Development of an ELISA for detection of parathion, carbofuran, and 2,4-dichlorophenoxyacetic acid in water, soil, vegetables, and fruits

Razak CN, Salam F, Ampon K, Basri M, Salleh AB

Ann N Y Acad Sci, 1998 Dec 13;864:479-84.
PMID: 9928128
Matched MeSH terms: Enzyme-Linked Immunosorbent Assay/methods
Pathotyping of Newcastle disease virus with a filamentous bacteriophage

Ramanujam P, Tan WS, Nathan S, Yusoff K

Biotechniques, 2004 Feb;36(2):296-300, 302.
PMID: 14989094

A filamentous phage bearing the peptide sequence TLTTKLY was isolated from a heptapeptide phage display library against a velogenic Newcastle disease virus (NDV). In order to investigate the potential of this specific phage as an immunological reagent in virus pathotyping, an enzyme-linked immunosorbent assay (ELISA)-based method was developed. This method can differentiate the velogenic strains from the mesogenic and lentogenic strains. An equilibrium-binding assay in solution showed that the interactions between the phage and all the NDV strains gave rise to two widely differing dissociation constants (Kdrel). Based upon the first Kdrel values, NDV strains can be classified into two groups; the first comprises the velogenic strains, and the second consists of the mesogenic and lentogenic strains. These results indicate a high degree of correlation between the binding affinities and pathotyping of NDV strains using the TLTTKLY phage.

Matched MeSH terms: Enzyme-Linked Immunosorbent Assay/methods
Development of an Antigen Detection ELISA for Bancroftian Filariasis Using BmSXP-Specific Recombinant Monoclonal Antibody

Rahumatullah A, Lim TS, Yunus MH, Noordin R

Am J Trop Med Hyg, 2019 08;101(2):436-440.
PMID: 31162018 DOI: 10.4269/ajtmh.19-0034

Lymphatic filariasis is a mosquito-borne parasitic disease responsible for morbidity and disability that affects 1.2 billion people worldwide, mainly the poor communities. Currently, filarial antigen testing is the method of choice for the detection of bancroftian filariasis, and to date, there are two commonly used tests. In the present study, a recently reported recombinant monoclonal antibody (5B) specific to BmSXP filarial antigen was used in developing an ELISA for the detection of circulating filarial antigen in sera of patients with bancroftian filariasis. The performance of the ELISA was evaluated using 124 serum samples. The ELISA was positive with all sera from microfilaremic bancroftian filariasis patients (n = 34). It also showed 100% diagnostic specificity when tested with sera from 50 healthy individuals and 40 patients with other parasitic diseases. The developed assay using the novel 5B recombinant monoclonal antibody could potentially be a promising alternative antigen detection test for bancroftian filariasis.

Matched MeSH terms: Enzyme-Linked Immunosorbent Assay/methods*
Fulltext Comparative seroprevalences of bovine trypanosomiasis and anaplasmosis in five states of Malaysia

Rahman WA, Fong S, Chandrawathani P, Nurulaini R, Zaini CM, Premalaatha B

Trop Biomed, 2012 Mar;29(1):65-70.
PMID: 22543604 MyJurnal

A comparative seroprevalence study on bovine trypanosomiasis and anaplasmosis was conducted. Sera of adult cattle and buffaloes of different breeds from farms from five different states in Malaysia were collected and tested for the presence of Trypanosoma evansi antibodies by CATT and Anaplasma marginale antibodies by c-ELISA. Of the 116 samples, 14.7% tested positive for bovine trypanosomiasis and 77.6% for bovine anaplasmosis.

Matched MeSH terms: Enzyme-Linked Immunosorbent Assay/methods
A recombinant antigen-based IgG4 ELISA for the specific and sensitive detection of Brugia malayi infection

Rahmah N, Lim BH, Khairul Anuar A, Shenoy RK, Kumaraswami V, Lokman Hakim S, et al.

Trans R Soc Trop Med Hyg, 2001 8 9;95(3):280-4.
PMID: 11490997

An IgG4 ELISA based on a novel recombinant antigen was evaluated for detection of Brugia malayi infection, using 2487 sera from various institutions: 2031 samples from Universiti Sains Malaysia, 276 blinded sera from 2 other institutions in Malaysia, 140 blinded sera from India and 40 blinded sera from Thailand. These sera were from various groups of individuals, i.e., microfilaraemics, chronic patients, endemic normals, non-endemic normals and individuals with other parasitic and bacterial infections. Based on a cut-off optical density reading of 0.300, the IgG4 ELISA demonstrated specificity rates of 95.6-100%, sensitivity rates of 96-100%, positive predictive values of 75-100% and negative predictive values of 98.9-100%. These evaluation studies demonstrated the high specificity and sensitivity of this test for the detection of active B. malayi infection. Thus, the IgG4 ELISA would be very useful as a tool in diagnosis and in elimination programmes for brugian filariasis.

Matched MeSH terms: Enzyme-Linked Immunosorbent Assay/methods*
PCR-ELISA for the detection of Brugia malayi infection using finger-prick blood

Rahmah N, Ashikin AN, Anuar AK, Ariff RH, Abdullah B, Chan GT, et al.

Trans R Soc Trop Med Hyg, 1998 12 16;92(4):404-6.
PMID: 9850392

A polymerase chain reaction assay based on the enzyme-linked immunosorbent assay (PCR-ELISA) has been developed to detect Brugia malayi infection in an area of low endemicity in Malaysia. Blood samples from 239 subjects were tested: 192 amicrofilaraemic individuals, 14 microfilaraemic persons and 3 chronic elephantiasis cases from endemic areas and 30 city-dwellers (non-endemic controls). PCR products were examined by ELISA and Southern hybridization. In the PCR-ELISA, digoxigenin-labelled PCR products were hybridized to a biotin-labelled probe. This was followed by incubation in streptavidin-coated microtitre wells and detection using anti-digoxigenin-peroxidase and ABTS [2,2'-azinobis(3-ethylbenzthiazoline-6-sulphonic acid)]. All microfilaraemic samples were positive by PCR-ELISA and Southern hybridization and all samples from non-endemic subjects and chronic elephantiasis patients were negative. The PCR-ELISA detected 12 times as many B. malayi infections as did thick blood film examination. Nineteen of the 194 samples from the endemic area gave positive results by both PCR-ELISA and Southern hybridization, and an additional 5 samples were positive by PCR-ELISA only. The PCR-ELISA was specific and sensitive, detected more infections, and was more reproducible than Southern hybridization.

Matched MeSH terms: Enzyme-Linked Immunosorbent Assay/methods
Potential use of IgG2-ELISA in the diagnosis of chronic elephantiasis and IgG4-ELISA in the follow-up of microfilaraemic patients infected with Brugia malayi

Rahmah N, Anuar AK, Karim R, Mehdi R, Sinniah B, Omar AW

Biochem Biophys Res Commun, 1994 Nov 30;205(1):202-7.
PMID: 7999024

Sera from fifty subjects with different presentations of Brugian filariasis and from common soil-transmitted helminth infections were tested for specific anti-filarial IgG and its subclasses. Anti-filarial IgG, IgG1 and IgG3 showed cross-reactivities with soil-transmitted helminthic infections and no significant differences in optical densities among the various groups of filarial patients. In comparison with other groups of subjects, IgG4-ELISA of sera from microfilaraemic patients and some previously microfilaraemic patients showed a significant increase in optical density readings, while IgG2-ELISA showed elevated optical density readings in sera of patients with chronic elephantiasis. Therefore IgG2-ELISA is potentially useful in the diagnosis of brugian chronic elephantiasis while IgG4-ELISA may be beneficial for follow-up diagnosis of treated microfilaraemic patients.

Matched MeSH terms: Enzyme-Linked Immunosorbent Assay/methods*
Short communication: use of a recombinant antigen-based ELISA to determine prevalence of brugian filariasis among Malaysian schoolchildren near Pasir Mas, Kelantan-Thailand border

Rahmah N, Lim BH, Azian H, Ramelah TS, Rohana AR

Trop Med Int Health, 2003 Feb;8(2):158-63.
PMID: 12581442

Brugian filariasis infects 13 million people in Asia. The routine prevalence survey method using night thick blood smear is not sensitive enough to reflect the actual infection prevalence. In 1997-2001, only three microfilaraemic cases (of 5601 individuals screened; 0.05%) were reported in Pasir Mas, a district in Kelantan (Malaysia), which shares a border with Thailand. We therefore investigated the infection prevalence in this district by employing a sensitive and specific serological assay (Brugia-Elisa). This test is based on detection of specific IgG4 antibody against a Brugia malayi recombinant antigen. A total of 5138 children, aged 7-12 years, from 16 primary schools, were tested. Eighteen pupils in eight schools, located in five subdistricts, tested positive, giving an overall prevalence rate of 0.35%. Infection in these children is significant as they represent more recent cases. These subdistricts should be included in the national filariasis elimination programme.

Matched MeSH terms: Enzyme-Linked Immunosorbent Assay/methods
Use of antifilarial IgG4-ELISA to detect Brugia malayi infection in an endemic area of Malaysia

Rahmah N, Anuar AK, Ariff RH, Zurainee MN, A'shikin AN, Fadzillah A, et al.

Trop Med Int Health, 1998 Mar;3(3):184-8.
PMID: 9593356

OBJECTIVE: To evaluate the usefulness of antifilarial IgG4 antibody assay in detecting B. malayi infection in a filaria endemic area in Malaysia.
METHODS: A sandwich ELISA using B. malayi soluble antigen was employed to detect antifilarial IgG4 antibodies in serum samples of 330 individuals who comprised 88 healthy individuals from nonendemic areas, 15 B. malayi microfilaraemic cases, 22 individuals with soil-transmitted helminthiases, 9 elephantiasis cases and 196 residents from a B. malayi-endemic area. An O.D. value of > 0.420 at serum dilution of 1:400 was used as the cut-off point. This cut-off point was obtained by taking the mean optical density (0.252 + 4 S.E.) of 36 negative sera which had O.D. values greater than 0.1 at serum dilution of 1:400.
RESULTS: All 15 microfilaraemic persons were positive for antifilarial IgG4 antibody. Non-endemic normals, soil-transmitted helminth infected persons and chronic elephantiasis cases were negative for antifilarial IgG4 antibody. Of the 196 individuals from the filaria endemic area, 37 (18.8%) demonstrated presence of antifilarial IgG4 antibodies; and only eight individuals (4.1%) were positive for microfilariae. All eight microfilaraemic individuals were also positive for antifilarial IgG4 antibodies.
CONCLUSION: Antifilarial IgG4-ELISA could detect 4.6 times more positive cases than the microfilaria detection method. With appropriate cut-off values that eliminate cross-reactivities, this serological tool is very useful for Brugia malayi prevalence surveys and diagnosis.

Matched MeSH terms: Enzyme-Linked Immunosorbent Assay/methods
Fulltext Daily supplementation of tocotrienol-rich fraction or alpha-tocopherol did not induce immunomodulatory changes in healthy human volunteers

Radhakrishnan AK, Lee AL, Wong PF, Kaur J, Aung H, Nesaretnam K

Br J Nutr, 2009 Mar;101(6):810-5.
PMID: 18702848 DOI: 10.1017/S0007114508039998

Vitamin E is divided into two subgroups; tocopherols and tocotrienols. Both have protective roles in biological systems. The present study was conducted to compare the effect of short-term supplementation at 200 mg/d of either alpha-tocopherol or a tocotrienol-rich fraction (TRF) from palm oil on immune modulation and plasma vitamin E levels in normal healthy Asian volunteers. In a randomised, double-blind placebo-controlled trial conducted, fifty-three healthy volunteers aged 20-50 years were recruited based on the study's inclusion and exclusion criteria. They were randomly assigned into three groups, i.e. two experimental groups that received daily supplementation at 200 mg of either alpha-tocopherol or the TRF, and the control group that received a placebo. Blood was drawn on days 0, 28 and 56 for several laboratory analyses. Differences in the production of IL-4 or interferon-gamma by concanavalin A-stimulated lymphocytes isolated from these volunteers were not significant (P>0.05). There were no significant differences observed in immune parameters between the healthy volunteers who received daily supplementation with either alpha-tocopherol or the TRF. As these observations were made in the absence of any immunogenic challenge, we feel it would be of benefit to study if there would be any differences observed when an immunogenic challenge such as vaccination were introduced.

Matched MeSH terms: Enzyme-Linked Immunosorbent Assay/methods
Fulltext Cloning, expression, and immunocharacterization of surface protein containing an altered thrombospondin repeat domain (SPATR) from Plasmodium knowlesi

Palaeya V, Lau YL, Mahmud R, Chen Y, Fong MY

Malar J, 2013;12:182.
PMID: 23734702 DOI: 10.1186/1475-2875-12-182

Plasmodium knowlesi is the fifth species identified to cause malaria in humans and is often misdiagnosed as Plasmodium malariae due to morphological similarities. The development of an inexpensive, serological detection method utilizing antibodies specific to P. knowlesi would be a valuable tool for diagnosis. However, the identification of specific antigens for these parasites remains a major challenge for generating such assays. In this study, surface protein containing an altered thrombospondin repeat domain (SPATR) was selected as a potentially specific antigen from P. knowlesi. Its multistage expression by sporozoites, asexual erythrocytic forms and gametocytes, along with its possible role in liver cell invasion, suggests that SPATR could be used as a biomarker for diagnosis of P. knowlesi.

Matched MeSH terms: Enzyme-Linked Immunosorbent Assay/methods
A preliminary study of dengue infection in Brunei

Osman O, Fong MY, Devi S

Jpn J Infect Dis, 2007 Jul;60(4):205-8.
PMID: 17642533

The purpose of this study was to examine the extent of dengue infection in Brunei and to determine the predominant serotype circulating in the country. The study generated useful epidemiological data on dengue infection in Brunei. A total of 271 samples from patients suspected of having dengue infections were selected and analyzed. All patients were seen in clinics and hospitals in Brunei. The samples were collected from April 2005 to April 2006 and transported to the WHO Collaborating Centre for Arbovirus Reference and Research, University of Malaya, Malaysia. The following tests were used to achieve the objectives: in-house IgM-capture enzyme-linked immunosorbent assay, virus isolation in mosquito albopictus cell line (C6/36), and viral RNA detection and serotyping by reverse transcriptase-polymerase chain reaction (RT-PCR). The results show that 45 people were positive for dengue-specific IgM (27 males and 18 females), while RT-PCR detected dengue viral RNA in 12 patients, 3 identified as DEN-1 and 9 as DEN-2. Dengue virus was isolated from 6 patients using the C6/36 cell line; 3 were DEN-2 isolates and 3 were DEN-1 isolates. These data show that dengue virus is circulating in Brunei and the predominant infecting serotype for that period was DEN-2 followed by DEN-1. This study is the first to report the detection and isolation of dengue virus from Brunei using RT-PCR and culture in the C6/36 albopictus mosquito cell line.

Matched MeSH terms: Enzyme-Linked Immunosorbent Assay/methods
Development and application of dot-enzyme-linked immunosorbent (dot-ELISA) assay for detection of Brucella melitensis and evaluation of the shedding pattern in infected goats

Onilude OM, Mohd Yusoff S, Emikpe BO, Tanko P, Shahrom SM, Effendy M

J Immunoassay Immunochem, 2017;38(1):82-99.
PMID: 27494045 DOI: 10.1080/15321819.2016.1220395

Early and accurate diagnosis of Brucella melitensis is essential for the treatment and control of brucellosis both in animals and humans. The thrust for the development of a rapid diagnostic technique to overcome the limitations of conventional microbiological and serological tests brought about this investigation on the development and application of dot-ELISA for antigen and antibody detection in infected goats. Fifteen apparently healthy Boer aged 2-3 years which tested negative for brucellosis using PCR and ELISA, were grouped into A (10 goats infected intraocularly with 10(7) CFU of B. melitensis) and B (5 goats) as control. Discharges (ocular, nasal, and vaginal) and blood were collected at days 3, 7, 10, 14, weekly until 42 post-infection (pi) for dot-ELISA, PCR, and RBPT. Dot-ELISA detected B. melitensis antigen and antibody in group A at day 3 and 7 pi, respectively with adequate sensitivity and specificity relative to PCR and RBPT. The bacteria shedding detected from discharges at day 3 pi in the nasal and ocular route with dot-ELISA. Group B were consistently negative. Values such as speed, simplicity, field adaptability, high sensitivity, and specificity make dot-ELISA a rapid and adequate technique for diagnosis of brucellosis in B. melitensis infected goats within few hours.

Matched MeSH terms: Enzyme-Linked Immunosorbent Assay/methods*
Fulltext Multi-isotype antibody responses against the multimeric Salmonella Typhi recombinant hemolysin E antigen

Ong EB, Ignatius J, Anthony AA, Aziah I, Ismail A, Lim TS

Microbiol. Immunol., 2015 Jan;59(1):43-7.
PMID: 25399538 DOI: 10.1111/1348-0421.12211

The detection and measurement of different antibody isotypes in the serum provide valuable indicators of the different stages of typhoid infection. Here, the ability of S. Typhi recombinant hemolysin E (HlyE) to detect multi-isotype antibody responses in sera of patients with typhoid and paratyphoid A was investigated using an indirect antibody immunoassay. Nanogram amounts of HlyE were found to be sufficient for detection of IgG and IgA isotypes and, in a study of individuals' sera (n = 100), the immunoassay was able to distinguish between typhoid and non-typhoid sera. The overall sensitivity, specificity and efficiency of the ELISA were 70% (39/56), 100% (44/44) and 83% respectively.

Matched MeSH terms: Enzyme-Linked Immunosorbent Assay/methods
Cloning, expression, and purification of the hemolysin/cytolysin (HlyE antigen) from Salmonella enterica serovar Typhi: potential application for immunoassay development

Ong EB, Anthony AA, Ismail A, Ismail A, Lim TS

Diagn Microbiol Infect Dis, 2013 Sep;77(1):87-9.
PMID: 23790417 DOI: 10.1016/j.diagmicrobio.2013.05.010

The hemolysin (HlyE) protein of Salmonella enterica serovar Typhi was reported to be antigenic. This work describes the cloning, expression, and purification of a hexahistidine-tagged HlyE protein under native conditions. Immunoblot analysis and a competitive enzyme-linked immunosorbent assay using sera from typhoid patients showed the presence of HlyE-specific antibodies in circulation.

Matched MeSH terms: Enzyme-Linked Immunosorbent Assay/methods
rTES-30USM: cloning via assembly PCR, expression, and evaluation of usefulness in the detection of toxocariasis

Norhaida A, Suharni M, Liza Sharmini AT, Tuda J, Rahmah N

Ann Trop Med Parasitol, 2008 Mar;102(2):151-60.
PMID: 18318937 DOI: 10.1179/136485908X252250

Currently, the laboratory diagnosis of toxocariasis, caused by Toxocara canis or T. cati, mainly relies on serological tests. Unfortunately, however, the specificities of most of the commercial tests that are available for the serodiagnosis of this disease are not very high and this may cause problems, especially in tropical countries where co-infections with other helminths are common. In an effort to develop a serological assay with improved specificity for the detection of Toxocara infection, an IgG(4)-ELISA based on a recombinant version (rTES-30USM) of the 30-kDa Toxocara excretory-secretory antigen (TES-30) has recently been developed. To produce the antigen, the TES-30 gene was cloned via assembly PCR, subcloned into a His-tagged prokaryotic expression vector, and purified by affinity chromatography using Ni(2+)-nitrilotriacetic-acid (Ni-NTA) resin. The performance of the ELISA based on the recombinant antigen was then compared with that of commercial kit, based on an IgG-ELISA, for the serodiagnosis of toxocariasis (Toxocara IgG-ELISA; Cypress Diagnostics, Langdorp, Belgium). Both assays were used to test 338 serum samples, including 26 samples from probable cases of toxocariasis. Assuming that all the probable cases were true cases, the assay based on rTES-30USM demonstrated a sensitivity of 92.3% (24/26) and a specificity of 89.6% (103/115) whereas the commercial kit exhibited a sensitivity of 100% (26/26) but a specificity of only 55.7% (64/115). The high sensitivity and specificity exhibited by the new IgG(4)-ELISA should make the assay a good choice for use in tropical countries and any other area where potentially cross-reactive helminthic infections are common.

Matched MeSH terms: Enzyme-Linked Immunosorbent Assay/methods*
Comparison of IgG-ELISA and IgG4-ELISA for Toxocara serodiagnosis

Noordin R, Smith HV, Mohamad S, Maizels RM, Fong MY

Acta Trop, 2005 Jan;93(1):57-62.
PMID: 15589798

Diagnosis of human toxocariasis, caused by Toxocara canis or Toxocara cati, normally relies on a combination of the presence of clinical signs and symptoms backed by positive serology. The use of Toxocara excretory-secretory antigen (TES) in ELISA assays increases the test specificity. However, in tropical countries where soil-transmitted helminths are endemic, cross-reactivity from antibodies to these intestinal parasites poses a significant limitation for Toxocara serodiagnosis. To increase the specificity of serodiagnosis, we compared the use of IgG-ELISA to the use of IgG4-ELISA using commercially manufactured TES-coated plates. The sensitivity of the IgG-ELISA was 97.1%, while that of the IgG4-ELISA was 45.7%; the specificities were 36.0 and 78.6%, respectively. The study shows that employing both assays can improve the serodiagnosis of toxocariasis. An IgG4 immunoassay would also be useful in the secondary screening of antigen clones in the effort to develop improved serological tests for toxocariasis.

Matched MeSH terms: Enzyme-Linked Immunosorbent Assay/methods*

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links