Displaying publications 81 - 100 of 109 in total

  1. Arifin N, Yunus MH, Nolan TJ, Lok JB, Noordin R
    Am J Trop Med Hyg, 2018 04;98(4):1165-1170.
    PMID: 29436335 DOI: 10.4269/ajtmh.17-0697
    Strongyloides stercoralis is a human parasite that can cause a long-term infection. In immunosuppressed patients, strongyloidiasis may be fatal when there is overwhelming autoinfection resulting in the migration of large numbers of larvae through many organs. Definitive diagnosis is still a challenge, and a combination of symptoms, microscopic identification, and serology test results are often used to arrive at a clinical decision. However, intermittent larval excretion, low parasite burden, and occult infections are challenges with parasitological diagnosis of infection with S. stercoralis. Meanwhile, serologic tests using immunoglobulin G and parasite antigen extract have problems of cross-reactivity with other helminthic infections. Recombinant antigen-based serodiagnosis is a good alternative to overcome the laboratory diagnostic issues. Herein, we report on the isolation of cDNA clone encoding an antigen of potential diagnostic value identified from immunoscreening of a S. stercoralis cDNA library. The translated protein had highest similarity to Strongyloides ratti immunoglobulin-binding protein 1. The recombinant antigen produced, rSs1a, was assessed using western blot and enzyme-linked immunosorbent assay. The latter showed 96% diagnostic sensitivity and 93% specificity; thus, rSs1a has good potential for use in serodiagnosis of human strongyloidiasis.
  2. Arifin N, Basuni M, Lan CA, Yahya AR, Noordin R
    Protein J, 2010 Oct;29(7):509-15.
    PMID: 20845068 DOI: 10.1007/s10930-010-9281-1
    This paper describes a refinement in the purification step that facilitated the downstream recovery of high purity BmR1 recombinant protein, which is a protein used as a test reagent in the commercialized rapid tests for detection of lymphac filariasis i.e. Brugia Rapid™ and panLF rapid™. Purification was performed by immobilized metal affinity chromatography (IMAC), followed by ion exchange chromatography (IEX). Results showed that a total of 10.27 mg of BmR1 was obtained when IMAC was performed using 20 mM of imidazole and 5 column volume of wash buffer containing 500 mM of NaCl. Purity of the target protein was enhanced when buffer at pH 5.8 was used during the IEX. Two proteins that recurrently appeared below the BmR1 recombinant protein were identified by mass-spectrometry analysis as the same protein, thus they were probably degradation products of BmR1. These strategies improve purity of the target protein to be used in applications such as production of aptamers and monoclonal antibodies.
  3. Noordin R, Khanbabaie S, Hafiznur Yunus M, Marti H, Nickel B, Fasihi Harandi M, et al.
    Iran J Parasitol, 2020 10 22;15(3):290-298.
    PMID: 33082792 DOI: 10.18502/ijpa.v15i3.4191
    Background: Human echinococcosis is a neglected zoonotic disease distributed worldwide. It comprises cystic and alveolar forms, the former being the more prevalent disease. Imaging techniques are the first choice for diagnosis of cystic echinococcosis and serology is used as an additional diagnostic technique in doubtful cases or as the sole test in low-resource settings. Rapid diagnostic tests are useful and convenient for immunodiagnosis of cystic echinococcosis in endemic areas, where medical facilities often struggle with limited resources.

    Methods: Recently, we have developed Hyd Rapid™, an IgG4 lateral flow dipstick test using recombinant antigen B1 for detection of cystic echinococcosis. This study was performed between 2016 until 2018 at the Institute for Research in Molecular Medicine, Universiti Sains Malaysia. The diagnostic performance of Hyd Rapid™ was tested in-house and at two international laboratories in Switzerland and Iran.

    Results: The overall diagnostic sensitivity for detection of cystic and alveolar echinococcosis was 95% (56/59). Meanwhile, the diagnostic specificity, with and without exclusion of cysticercosis and fascioliasis, was 100% (n=48) and 88% (63/72), respectively.

    Conclusion: Hyd Rapid™ detected cystic echinococcosis as well as probable cases of alveolar echinococcosis. Therefore, Hyd Rapid™ showed good potential as a serological tool for echinococcosis, and merits further evaluation.

  4. Abdo AIK, Ngoh YY, Lew MH, Dass SA, Rahumatullah A, Noordin R, et al.
    PMID: 33258152 DOI: 10.1002/bab.2082
    Lymphatic filariasis is a neglected parasitic disease that affects millions in tropical and subtropical countries and is caused by Wuchereria and Brugia species. Specific and sensitive detection methods are essential in mapping infected areas where rapid tests are needed to cover underdeveloped and remote regions, which facilitates eliminating the disease as a public health problem. A few commercialized rapid tests based on antigen or antibody detection are available, but the former only detects infection by Wuchereria species and cross-reacts with nonlymphatic filaria, whereas antibody detection might provide positive results of previous infection. Here, we report the production of three different recombinant immunoglobulin gamma (IgG)1 antibodies based on scFvs previously generated via human antibody phage display technology, that is, anti-BmR1 clone 4, anti-BmXSP clone 5B, and anti-BmXSP clone 2H2. The scFv sequences were cloned into a pCMV-IgG1 vector, then transfected into a HEK293F cell line. The generated antibodies were found to be able to bind to their respective targets even at relatively low concentration. Conjugation of Fc to scFv induces binder stability and provides multiple labeling sites for probes and signaling molecules that can be used in rapid tests.
  5. Rahumatullah A, Ahmad A, Noordin R, Lai JY, Baharudeen Z, Lim TS
    Exp Parasitol, 2020 Dec;219:108029.
    PMID: 33096112 DOI: 10.1016/j.exppara.2020.108029
    Echinococcus granulosus is a worldwide zoonotic infection that causes human cystic echinococcosis (CE) or hydatid disease. The present study describes the isolation and production of a monoclonal antibody against recombinant AgB protein using the developed Human AntibodY Disease ENhanced (HAYDEN)-Filariasis library. The DNA sequences of the isolated clones were analyzed, followed by gene analysis and binding assays. Clone E1 showed a full-length sequence and represents the IgHV5-LV3 antibody gene family. The antibody protein yield was satisfactory, and it reacted specifically against rAgB. The novel E1 protein is potentially useful for the development of an antigen detection assay for CE. The ability of the Brugia malayi immune antibody library to isolate antibodies against Echinococcus granulosus antigens highlights the broad coverage of immune antibody libraries.
  6. Khan AH, Khanbabaie S, Yunus MH, Mohd Zain SN, Mohd Baharudeen Z, Sahimin N, et al.
    J Immigr Minor Health, 2020 Oct;22(5):1105-1108.
    PMID: 32445161 DOI: 10.1007/s10903-020-01029-y
    Hydatid disease is not endemic in Malaysia; however, its migrant workers originate from neighboring countries where the disease is prevalent. Thus, this study was aimed at investigating the seroprevalence of hydatid disease among the workers. A total of 479 migrant workers were screened for hydatid disease. The sociodemographic information was collected, and serum samples were tested with a rapid dipstick test for hydatid disease called Hyd Rapid™. The present study showed that 13.6% of the migrant workers were found to be seropositive for hydatid disease. The highest seroprevalence was seen among Indian workers (29.41%), followed by Myanmarese (21.43%), Bangladeshis (14.92%), Nepalese (10.68%), and Indonesian (10.66%). This is the first study that highlights the likely presence of hydatid disease among the migrant workers in Malaysia, which may be of interest to the health authorities.
  7. Tan ZN, Wong WK, Noordin R, Zeehaida M, Olivos GA, Lim BH
    Trop Biomed, 2013 Jun;30(2):250-6.
    PMID: 23959490 MyJurnal
    Entamoeba histolytica causes amoebic diarrhoea, colitis and liver abscess (ALA). Diagnosis of ALA is difficult, as most patients do not have simultaneous intestinal amoebic infection. At Hospital Universiti Sains Malaysia (HUSM), diagnosis of ALA relies on a combination of clinical findings, ultrasound examination of the liver and serodiagnosis using a commercial kit. In this study, two in-house indirect ELISAs were developed and evaluated. One of the in-house assays utilises E. histolytica crude soluble antigen (CSA) to detect serum IgG specific to the parasite whereas the other uses E. histolytica ether extract antigen (EEA). Preparation of CSA requires a sonicator to lyse the amoeba whereas EEA was prepared by chemically solubilizing the trophozoites. Based on the cut-off value of mean optical density + 3SD, CSA-ELISA showed 100% (24/24) sensitivity and 93.33% (210/225) specificity; while EEA-ELISA showed 91.67% (22/24) sensitivity and 95.11% (214/225) specificity. In conclusion, both the in-house indirect ELISAs were found to be efficacious for diagnosis of ALA; and the EEA is easier to prepare than the commonly used CSA.
  8. Tan AA, Azman SN, Abdul Rani NR, Kua BC, Sasidharan S, Kiew LV, et al.
    Trop Biomed, 2011 Dec;28(3):620-9.
    PMID: 22433892 MyJurnal
    There is a great diversity of protein samples types and origins, therefore the optimal procedure for each sample type must be determined empirically. In order to obtain a reproducible and complete sample presentation which view as many proteins as possible on the desired 2DE gel, it is critical to perform additional sample preparation steps to improve the quality of the final results, yet without selectively losing the proteins. To address this, we developed a general method that is suitable for diverse sample types based on phenolchloroform extraction method (represented by TRI reagent). This method was found to yield good results when used to analyze human breast cancer cell line (MCF-7), Vibrio cholerae, Cryptocaryon irritans cyst and liver abscess fat tissue. These types represent cell line, bacteria, parasite cyst and pus respectively. For each type of samples, several attempts were made to methodically compare protein isolation methods using TRI-reagent Kit, EasyBlue Kit, PRO-PREP™ Protein Extraction Solution and lysis buffer. The most useful protocol allows the extraction and separation of a wide diversity of protein samples that is reproducible among repeated experiments. Our results demonstrated that the modified TRI-reagent Kit had the highest protein yield as well as the greatest number of total proteins spots count for all type of samples. Distinctive differences in spot patterns were also observed in the 2DE gel of different extraction methods used for each type of sample.
  9. Rahumatullah A, Balachandra D, Noordin R, Baharudeen Z, Lim YY, Choong YS, et al.
    Sci Rep, 2021 01 28;11(1):2502.
    PMID: 33510342 DOI: 10.1038/s41598-021-82125-3
    Antibodies have different chemical properties capable of targeting a diverse nature of antigens. Traditionally, immune antibody libraries are perceived to be disease-specific with a skewed repertoire. The complexity during the generation of a combinatorial antibody library allows for a skewed but diverse repertoire to be generated. Strongyloides stercoralis is a parasite that causes strongyloidiasis, a potentially life-threatening disease with a complex diagnosis that impedes effective control and treatment of the disease. This study describes the isolation of monoclonal antibodies against S. stercoralis NIE recombinant protein using an immune antibody phage display library derived from lymphatic filaria-infected individuals. The isolated antibody clones showed both lambda and kappa light chains gene usage, with diverse amino acid distributions. Structural analysis showed that electropositivity and the interface area could determine the binding affinity of the clones with NIE. The successful identification of S. stercoralis antibodies from the filarial immune library highlights the breadth of antibody gene diversification in an immune antibody library that can be applied for closely related infections.
  10. Kumarasamy G, Abdus Sani AA, Olivos-García A, Noordin R, Othman N
    Pathog Glob Health, 2020 09;114(6):333-342.
    PMID: 32536281 DOI: 10.1080/20477724.2020.1780402
    Amoebiasis, caused by Entamoeba histolytica, is one of the leading parasitic infections in the world. This study was aimed at profiling antigenic membrane proteins of a virulent variant of E. histolytica HM-1:IMSS. The membrane proteins were extracted using ProteoExtract® kit (Merck, Darmstadt, Germany) or conventional method, separated using OFFGEL 3100 fractionator (Agilent Technologies, Santa Clara, California), followed by SDS-PAGE and Western blot analysis. Selected antigenic membrane proteins were identified using LC-ESI-MS/MS. Subsequently, the proteins were classified according to their biological processes and predictions were made on membrane and membrane-associated proteins. When the proteins were probed with pooled sera from amoebic liver abscess (ALA) patients, 10 and 15 antigenic proteins with molecular weights 25 to 200 kDa were identified using the ProteoExtract® kit and conventional method, respectively. LC-ESI-MS/MS identified 13 antigenic proteins, and both extraction methods predicted six of them as membrane and membrane-associated proteins. The topmost biological processes which comprised of six proteins were involved in cellular processes.. These antigenic membrane proteins merit further investigations as potential candidates for vaccine studies.
  11. Noordin R, Osman E, Anuar NS, Juri NM, Rahumatullah A, Hilmi NAA
    Am J Trop Med Hyg, 2021 Aug 30.
    PMID: 34460427 DOI: 10.4269/ajtmh.21-0674
    A lateral flow rapid test for strongyloidiasis will greatly facilitate the control and elimination of the disease. Previously SsRapid™ prototype rapid test showed high diagnostic specificity to detect Strongyloides infection, determined using non-Strongyloides sera negative by IgG-ELISAs. Since high specificity is crucial before a test is used for public health control activities, further validation of its specificity is needed. Also, it needs to be ascertained whether non-Strongyloides sera positive by IgG-ELISAs and SsRapid are truly positive for Strongyloides or are cases of cross-reactivity. We performed 84 rapid tests (two types of dipsticks and cassettes) using 34 serum samples. They were divided into four groups based on Strongyloides infection and coinfection with other parasites and the availability of recombinant proteins and rapid tests for the latter. Sera was adsorbed using polystyrene microspheres beads separately coated with four recombinant parasite proteins. The small sample size is a limitation of this study; however, the overall results showed that the sera adsorption procedure was successful, and the SsRapid test is specific.
  12. Balachandra D, Rahumatullah A, Lim TS, Mustafa FH, Ahmad H, Anuar NS, et al.
    Acta Trop, 2021 Sep;221:105986.
    PMID: 34058161 DOI: 10.1016/j.actatropica.2021.105986
    Serodiagnosis is an essential component of the laboratory diagnosis of Strongyloides infection and is usually performed using an indirect IgG antibody test. A direct antigen detection method can complement the IgG assay, particularly for detecting early infection and post-treatment follow-up. In the present study, a recombinant scFv monoclonal antibody against NIE recombinant protein (rMAb23) that we had previously produced was used to develop a Strongyloides antigen detection ELISA (SsAg-ELISA). The assay is based on detecting immune complexes of circulating NIE antigens bound to Strongyloides-specific IgG antibodies. The optimized ELISA parameters were 10 µg/mL of rMAb23 coated on microtitre plate wells, 2% skim milk as blocking reagent, 1:100 serum dilution, and 1:1000 goat anti-human IgG F(ab')2 conjugated to horseradish peroxidase. Four groups of serum samples were used, i.e., Strongyloides-positive serum samples categorized into Groups IA and IB; the former were from probable chronic infections and the latter from probable early/acute infections. Strongyloides-negative samples comprising Groups II (healthy samples) and III (other infections); the latter were from eleven different types of other parasitic infections. The receiver operating characteristic (ROC) curve showed an area under the curve (AUC) of 1.00, cut-off optical density (OD405) of 0.5002, and 100% diagnostic sensitivity and specificity. The results of the commercial IgG-ELISA and SsAg-ELISA from Group IA were found to be moderately correlated (r = 0.416; p 
  13. Sahimin N, Yunus MH, Douadi B, Yvonne Lim AL, Noordin R, Behnke JM, et al.
    Trop Biomed, 2019 Dec 01;36(4):1014-1026.
    PMID: 33597471
    The influx of low skilled migrant workers to Malaysia from low socio-economic countries where gastrointestinal parasitic infections are prevalent has raised concerns about transmission to the local population. Three methods for detection (serology, microscopy and molecular techniques) were utilized to identify Entamoeba infections amongst the targeted cohort and determine risk factors associated with infection. Serological screening of 484 migrant workers from five working sectors in Peninsular Malaysia using IgG4 ELISA based on the rPPDK antigen showed an overall seroprevalence of 7.4% (n = 36; CL95 = 5.3-10.1%) with only one factor statistically associated with seropositivity of anti-amoebic antibodies, i.e. years of residence in Malaysia (χ2 1 = 4.007, p = 0.045). Microscopic examination of 388 faecal samples for protozoan cysts and trophozoites showed a slightly higher prevalence (11.6%; n=45; CL95: 8.4-14.8%). Meanwhile, amplification of the 16S rDNA gene detected two species i.e. Entamoeba dispar (23/388; 5.9%; CL95: 3.6-8.3%) and E. histolytica (11/388; 2.8%; CL95: 1.2-4.5%) and mixed infections with both parasites in only three samples (3/388; 0.8%; CL95: 0.2-2.2%). Entamoeba dispar infection was significantly associated with those employed in food and domestic services (χ2 4 = 12.879, p = 0.012). However, none of the factors affected the prevalence of E. histolytica infection. Despite the low prevalence of E. histolytica in faecal samples of the study cohort, the presence of this pathogenic parasite still poses potential public health risks and calls for tighter control strategies based on better availability of chemotherapeutic treatment and accessibility to appropriate health education.
  14. Amerizadeh A, Khoo BY, Teh AY, Golkar M, Abdul Karim IZ, Osman S, et al.
    BMC Infect Dis, 2013;13:287.
    PMID: 23800344 DOI: 10.1186/1471-2334-13-287
    Toxoplasma gondii is an obligate intracellular zoonotic parasite of the phylum Apicomplexa which infects a wide range of warm-blooded animals, including humans. In this study in-vivo induced antigens of this parasite was investigated using in-vivo induced antigen technology (IVIAT) and pooled sera from patients with serological evidence of acute infection.
  15. Ning TZ, Kin WW, Noordin R, Cun ST, Chong FP, Mohamed Z, et al.
    BMC Infect Dis, 2013;13:144.
    PMID: 23514636 DOI: 10.1186/1471-2334-13-144
    Amoebic liver abscess (ALA) is the most frequent clinical presentation of extra-intestinal amoebiasis. The diagnosis of ALA is typically based on the developing clinical symptoms, characteristic changes on radiological imaging and serology. Numerous serological tests have been introduced for the diagnosis of ALA, either detecting circulating amoebic antigens or antibodies. However those tests show some pitfalls in their efficacy and/or the preparation of the tests are costly and tedious. The commercial IHA kit that used crude antigen was reported to be useful in diagnosis of ALA, however high antibody background in endemic areas may cause problems in its interpretation. Thus, discovery of well-defined antigen(s) is urgently needed to improve the weaknesses of current serodiagnostic tests.
  16. Amerizadeh A, Idris ZM, Khoo BY, Kotresha D, Yunus MH, Karim IZ, et al.
    Microb Pathog, 2013 Jan;54:60-6.
    PMID: 23044055 DOI: 10.1016/j.micpath.2012.09.006
    Toxoplasmosis is an infection caused by the parasite Toxoplasma gondii. Chronically-infected individuals with a compromised immune system are at risk for reactivation of the disease. In-vivo induced antigen technology (IVIAT) is a promising method for the identification of antigens expressed in-vivo. The aim of the present study was to apply IVIAT to identify antigens which are expressed in-vivo during T. gondii infection using sera from individuals with chronic toxoplasmosis. Forty serum samples were pooled, pre-adsorped against three different preparations of antigens, from each in-vitro grown T. gondii and Escherichia coli XLBlue MRF', and then used to screen a T. gondii cDNA expression library. Sequencing of DNA inserts from positive clones showed eight open reading frames with high homology to T. gondii genes. Expression analysis using quantitative real-time PCR showed that SAG1-related sequence 3 (SRS3) and two hypothetical genes were up-regulated in-vivo relative to their expression levels in-vitro. These three proteins also showed high sensitivity and specificity when tested with individual serum samples. Five other proteins namely M16 domain peptidase, microneme protein, elongation factor 1-alpha, pre-mRNA-splicing factor and small nuclear ribonucleoprotein F had lower RNA expression in-vivo as compared to in-vitro. SRS3 and the two hypothetical proteins warrant further investigation into their roles in the pathogenesis of toxoplasmosis.
  17. Ning TZ, Kin WW, Mustafa S, Ahmed A, Noordin R, Cheong TG, et al.
    Asian Pac J Trop Biomed, 2012 Jan;2(1):61-5.
    PMID: 23569836 DOI: 10.1016/S2221-1691(11)60191-3
    To compare the efficacy of three different tissue stains, namely haematoxylin and eosin (H&E), periodic-acid Schiff (PAS) and immunohistochemical (IHC) stains for detection of Entamoeba histolytica (E. histolytica) trophozoites in abscessed liver tissues of hamster.
  18. Basuni M, Muhi J, Othman N, Verweij JJ, Ahmad M, Miswan N, et al.
    Am J Trop Med Hyg, 2011 Feb;84(2):338-43.
    PMID: 21292911 DOI: 10.4269/ajtmh.2011.10-0499
    Soil-transmitted helminth infections remain a major public health burden in low- and middle-income countries. The traditional diagnosis by microscopic examination of fecal samples is insensitive and time-consuming. In this study, a pentaplex real-time polymerase chain reaction (PCR) was evaluated for the simultaneous detection of Ancylostoma, Necator americanus, Ascaris lumbricoides, and Strongyloides stercoralis. The results were compared with those obtained by conventional parasitological diagnostic methods. Real-time PCR was positive in 48 of 77 samples (62.3%) and microscopic examination was positive in six samples (7.8%) only (P < 0.05). In conclusion, the real-time PCR assay described in this study provides a specific and sensitive diagnostic tool for the detection of these four helminth species in epidemiological studies and monitoring of treatment programs.
  19. Wong WK, Foo PC, Olivos-Garcia A, Noordin R, Mohamed Z, Othman N, et al.
    Acta Trop, 2017 Aug;172:208-212.
    PMID: 28506795 DOI: 10.1016/j.actatropica.2017.05.017
    Crude soluble antigen (CSA) produced from Entamoeba histolytica trophozoite is conventionally used for serodiagnosis of invasive amoebiasis. However, high background seropositivities by CSA-assay in endemic areas complicate the interpretation of positive result in clinical settings. Instead, incorporating a second assay which indicates active or recent infection into the routine amoebic serology could possibly complement the limitations of CSA-assay. Hence, the present study aimed to evaluate the diagnostic efficacies of indirect ELISAs using CSA and excretory-secretory antigen (ESA) for serodiagnosis of amoebic liver abscess (ALA). Reference standard for diagnosis of ALA at Hospital Universiti Sains Malaysia is based on clinical presentation, radiological imaging and positive indirect haemagglutination assay (titer ≥256). Five groups of human serum samples collected from the hospital included Group I - ALA diagnosed by the reference standard and pus aspirate analysis using real-time PCR (n=10), Group II - ALA diagnosed by the reference standard only (n=41), Group III - healthy control (n=45), Group IV - other diseases control (n=51) and Group V - other infectious diseases control (n=31). For serodiagnosis of ALA serum samples (Group I and II), CSA-ELISA showed sensitivities of 100% for both groups, while ESA-ELISA showed sensitivities of 100% and 88%, respectively. For serodiagnosis of non-ALA serum samples (Group III, IV and V), CSA-ELISA showed specificities of 91%, 75% and 100%, respectively; while ESA-ELISA showed specificities of 96%, 98% and 100%, respectively. Indirect ELISAs using CSA and ESA have shown distinct strength for serodiagnosis of ALA, in terms of sensitivity and specificity, respectively. In conclusion, parallel analysis by both assays improved the overall efficacies of amoebic serology as compared to either single assay.
  20. Noordin R, Yunus MH, Saidin S, Mohamed Z, Fuentes Corripio I, Rubio JM, et al.
    Am J Trop Med Hyg, 2020 12;103(6):2233-2238.
    PMID: 32996457 DOI: 10.4269/ajtmh.20-0348
    Independent evaluations of XEh Rapid®, an IgG4-based rapid dipstick test, were performed to assess its diagnostic performance to detect amebic liver abscess (ALA) using 405 samples at seven laboratories in four countries. The test showed high diagnostic specificity (97-100%) when tested with samples from healthy individuals (n = 100) and patients with other diseases (n = 151). The diagnostic sensitivity was tested with a total of 154 samples, and the results were variable. It was high in three laboratories (89-94%), and moderate (72%) and low (38%) in two other laboratories. Challenges and issues faced in the evaluation process are discussed. Nevertheless, XEh Rapid is promising to be developed into a point-of-care test in particular for resource-limited settings, and thus merits further confirmation of its diagnostic sensitivity.
Contact Us

Please provide feedback to Administrator (tengcl@gmail.com)

External Links