Displaying publications 1 - 20 of 36 in total

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  1. Amini P, Abdullah M, Seng LS, Karunakaran T, Hani N, Bakar SA, et al.
    Int Forum Allergy Rhinol, 2016 Jun;6(6):624-30.
    PMID: 26919193 DOI: 10.1002/alr.21442
    BACKGROUND: The number of available reports regarding the influence of ethnicity on clinical features of allergic rhinitis (AR), especially disease severity in tropical climates, is limited. We aimed to compare clinical parameters and disease severity in AR patients of different ethnicities.

    METHODS: Malay, Chinese, and Indian AR patients (n = 138) with confirmed sensitivity to Dermatophagoides pteronyssinus, Dematophagoides farinae, and Blomia tropicalis were tested for mite-specific immunoglobulin E (sIgE) levels. A detailed questionnaire was used to collect data on nasal symptom score (NSS), ocular symptom score (OSS), sum of symptoms score (SSS), quality of life score (QLS), symptomatic control score (SCS), and total sum of scores (TSS) and correlate the derived data with patients' demography, mite-polysensitivity, and sIgE levels.

    RESULTS: AR-related symptoms were most severe in Malays and least in Chinese (p < 0.01). Age (r = 0.516 to 0.673, p < 0.05) and duration of AR (r = 0.635 to 0.726, p < 0.01) correlated positively with severity domains (NSS, SSS, QLS, and TSS) in Chinese. Duration of concurrent allergies was highest in Malays (p < 0.05). Polysensitivity predicted increased sIgE levels in Malays (r = 0.464 to 0.551, p < 0.01) and Indians (r = 0.541 to 0.645, p < 0.05) but affected NSS, SSS, and TSS only in Indians (r = 0.216 to 0.376, p < 0.05). sIgE levels were lowest among Chinese but correlated strongly with NSS, OSS, SSS, and TSS (r = 0408 to 0.898, p < 0.05).

    CONCLUSION: Clinical parameters in AR may be influenced by race. Symptoms were most severe among Malays but did not correlate with other variables examined. Although Indian ethnicity did not impact disease severity, duration of concurrent allergies and mite-polysensitivity was associated with more severe disease. Age, duration of disease, and sIgE levels may be useful indicators of disease severity in Chinese.

    Matched MeSH terms: Immunoglobulin E/immunology
  2. Sunderasan E, Bahari A, Arif SA, Zainal Z, Hamilton RG, Yeang HY
    Clin Exp Allergy, 2005 Nov;35(11):1490-5.
    PMID: 16297147 DOI: 10.1111/j.1365-2222.2005.02371.x
    BACKGROUND:
    Hev b 4 is an allergenic natural rubber latex (NRL) protein complex that is reactive in skin prick tests and in vitro immunoassays. On SDS-polyacrylamide gel electrophoresis (SDS-PAGE), Hev b 4 is discerned predominantly at 53-55 kDa together with a 57 kDa minor component previously identified as a cyanogenic glucosidase. Of the 13 NRL allergens recognized by the International Union of Immunological Societies, the 53-55 kDa Hev b 4 major protein is the only candidate that lacks complete cDNA and protein sequence information.

    OBJECTIVE:
    We sought to clone the transcript encoding the Hev b 4 major protein, and characterize the native protein and its recombinant form in relation to IgE binding.

    METHODS:
    The 5'/3' rapid amplification of cDNA ends method was employed to obtain the complete cDNA of the Hev b 4 major protein. A recombinant form of the protein was over-expressed in Escherichia coli. The native Hev b 4 major protein was deglycosylated by trifluoromethane sulphonic acid. Western immunoblots of the native, deglycosylated and recombinant proteins were performed using both polyclonal antibodies and sera from latex-allergic patients.

    RESULTS:
    The cDNA encoding the Hev b 4 major protein was cloned. Its open reading frame matched lecithinases in the conserved domain database and contained 10 predicted glycosylation sites. Detection of glycans on the Hev b 4 lecithinase homologue confirmed it to be a glycoprotein. The deglycosylated lecithinase homologue was discerned at 40 kDa on SDS-PAGE, this being comparable to the 38.53 kDa mass predicted by its cDNA. Deglycosylation of the lecithinase homologue resulted in the loss of IgE recognition, although reactivity to polyclonal rabbit anti-Hev b 4 was retained. IgE from latex-allergic patients also failed to recognize the non-glycosylated E. coli recombinant lecithinase homologue.

    CONCLUSION:
    The IgE epitopes of the Hev b 4 lecithinase homologue reside mainly in its carbohydrate moiety, which also account for the discrepancy between the observed molecular weight of the protein and the value calculated from its cDNA.
    Matched MeSH terms: Immunoglobulin E/immunology*
  3. Tan JW, Wan Zahidi NF, Kow ASF, Soo KM, Shaari K, Israf DA, et al.
    Biosci Rep, 2019 06 28;39(6).
    PMID: 31110077 DOI: 10.1042/BSR20181273
    Mast cells (MCs), a type of immune effector cell, have recently become recognized for their ability to cause vascular leakage during dengue virus (DENV) infection. Although MC stabilizers have been reported to attenuate DENV induced infection in animal studies, there are limited in vitro studies on the use of MC stabilizers against DENV induced MC degranulation. 2,4,6-trihydroxy-3-geranyl acetophenone (tHGA) has been reported to be a potential MC stabilizer by inhibiting IgE-mediated MC activation in both cellular and animal models. The present study aims to establish an in vitro model of DENV3-induced RBL-2H3 cells using ketotifen fumarate as a control drug, as well as to determine the effect of tHGA on the release of MC mediators upon DENV infection. Our results demonstrated that the optimal multiplicities of infection (MOI) were 0.4 × 10-2 and 0.8 × 10-2 focus forming units (FFU)/cell. Ketotifen fumarate was proven to attenuate DENV3-induced RBL-2H3 cells degranulation in this in vitro model. In contrast, tHGA was unable to attenuate the release of both β-hexosaminidase and tumor necrosis factor (TNF)-α. Nonetheless, our study has successfully established an in vitro model of DENV3-induced RBL-2H3 cells, which might be useful for the screening of potential MC stabilizers for anti-dengue therapies.
    Matched MeSH terms: Immunoglobulin E/immunology
  4. Kow ASF, Chik A, Soo KM, Khoo LW, Abas F, Tham CL
    Front Immunol, 2019;10:190.
    PMID: 30809224 DOI: 10.3389/fimmu.2019.00190
    Background: Anaphylaxis is an acute and life-threatening allergic response. Classically and most commonly, it can be mediated by the crosslinking of allergens to immunoglobulin E (IgE)- high affinity IgE receptor (FcεRI) complex found mostly on mast cells. However, there is another pathway of anaphylaxis that is less well-studied. This pathway known as the alternative pathway is mediated by IgG and its Fc gamma receptor (Fcγ). Though it was not documented in human anaphylaxis, a few studies have found that IgG-mediated anaphylaxis can happen as demonstrated in rodent models of anaphylaxis. In these studies, a variety of soluble mediators were being evaluated and they differ from each study which causes confusion in the suitability, and reliability of choice of soluble mediators to be analyzed for diagnosis or therapeutic purposes. Hence, the objective of this meta-analysis is to identify the potential soluble mediators that are involved in an IgG-mediated anaphylaxis reaction. Methods: Studies related to IgG-mediated anaphylaxis were sourced from five search engines namely PubMed, Scopus, Ovid, Cochrane Library, and Center for Agricultural Bioscience International (CABI) regardless of publication year. Relevant studies were then reviewed based on specific inclusion factors. The means and standard deviations of each soluble mediator studied were then extracted using ImageJ or Get Data Graph Digitiser software and the data were subjected to meta-analysis. Results: From our findings, we found that histamine, serotonin, platelet activating factor (PAF), β-hexosaminidase, leukotriene C4 (LTC4), mucosal mast cell protease-1 (MMCP-1), interleukins (IL)-4,-6, and-13; tumor necrosis factor alpha (TNF-α), and macrophage inflammatory protein-1α (MIP-1α) were often being analyzed. Out of these soluble mediators, histamine, PAF, β-hexosaminidase, IL-6, and-13, MIP-1α and TNF-α were more significant with positive effect size and p < 0.001. As study effect was relatively small, we performed publication bias and found that there was publication bias and this could be due to the small sample size studied. Conclusion: As such, we proposed that through meta-analysis, the potential soluble mediators involved in rodent IgG-mediated anaphylaxis to be histamine, PAF, β-hexosaminidase, IL-6 and-13 and MIP-1α, and TNF-α but will require further studies with larger sample size.
    Matched MeSH terms: Immunoglobulin E/immunology
  5. Ng SF, Anuwi NA, Tengku-Ahmad TN
    AAPS PharmSciTech, 2015 Jun;16(3):656-63.
    PMID: 25511806 DOI: 10.1208/s12249-014-0248-y
    Hydrocortisone cream intended for atopic eczema often produces unwanted side effects after long-term use. These side effects are essentially due to repeated percutaneous administration of the medication for skin dermatitis, as atopic eczema is a relapsing disorder. Hence, there is a need to develop a new hydrocortisone formulation that will deliver the drug more effectively and require a reduced dosing frequency; therefore, the side effects could be minimized. In this study, a hydroxypropyl methylcellulose (HPMC) lyogel system based on 80% organic and 20% aqueous solvents containing 1% hydrocortisone was formulated. The hydrocortisone lyogel physicochemical characteristics, rheological properties, stability profile, and in vitro Franz cell drug release properties, as well as the in vivo therapeutic efficacies and dermal irritancy in Balb/c mice were investigated. The HPMC lyogel appeared clear and soft and was easy to rub on the skin. The lyogel also showed a higher drug release profile compared with commercial hydrocortisone cream. Similar to the cream, HPMC lyogels exhibited pseudoplastic behavior. From the mouse model, the hydrocortisone lyogel showed higher inflammatory suppressive effects than the cream. However, it did not reduce the transepidermal water loss as effectively as the control did. The dermal irritancy testing revealed that the hydrocortisone lyogel caused minimal irritation. In conclusion, HPMC lyogel is a promising vehicle to deliver hydrocortisone topically, as it showed a higher drug release in vitro as well as enhanced therapeutic efficacy in resolving eczematous inflammatory reaction compared with commercial cream.
    Matched MeSH terms: Immunoglobulin E/immunology*
  6. Yeoh SM, Sam CK
    Asian Pac J Allergy Immunol, 2001 Mar;19(1):7-10.
    PMID: 11495303
    The significance of food specific serum IgG4 antibody in food allergy is unclear and this led us to investigate the relevance of specific IgG4, along with IgG and IgE antibodies to two common food allergens in Malaysia. Enzyme-linked immunosorbent assay (ELISA) was used to measure the serum antibodies in 143 allergic rhinitis patients' sera, of which 47 were from patients with clinical indication of shrimp allergy, 46 with clinical indication of crab allergy and 50 without indication to either allergy. Clinical indication of allergy was based on answers to a questionnaire or results of the skin prick test. We found that the elevation of specific IgE or IgG4 is associated with shrimp and crab allergies but elevation of specific IgG is not associated with either allergy. However, the clinical utility of elevated specific IgG and IgG4 levels is pending further investigation.
    Study site: Allergic rhinitis clinic, University Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia
    Matched MeSH terms: Immunoglobulin E/immunology*
  7. Hempolchom C, Sookrung N, Srisuka W, Reamtong O, Sakolvaree Y, Chaicumpa W, et al.
    Parasitol Res, 2019 Aug;118(8):2353-2359.
    PMID: 31263951 DOI: 10.1007/s00436-019-06383-x
    Simulium dermatitis is an IgE-mediated skin reaction in animals and humans caused by the bites of black flies. Although Simulium nigrogilvum has been incriminated as the main human-biting black fly species in Thailand, information on its salivary allergens is lacking. Salivary gland extract of S. nigrogilvum females was subjected to sodium dodecylsulfate-polyacrylamide gel electrophoresis, and the separated components were applied onto nitrocellulose membranes for immunoblotting, which was performed by probing the protein blots with sera from 17 individuals who were allergic to the bites of S. nigrogilvum. IgE-reactive protein bands were characterized further by liquid chromatography-mass spectrometry (LC-MS/MS) analysis. Nine protein bands (79, 42, 32, 25, 24, 22, 15, 13, and 11 kDa) were recognized in the serum of the subjects. Four of the nine protein bands (32, 24, 15, and 11 kDa) showed IgE reactivity in all (100%) of the tested sera, and they were identified as salivary secreted antigen 5-related protein, salivary serine protease, erythema protein, and hypothetical secreted protein, respectively. Three other proteins, salivary serine protease (25 kDa), salivary D7 secreted protein (22 kDa), and hypothetical protein (13 kDa), reacted with > 50% of the sera. The relevance of the identified protein bands as allergens needs to be confirmed by using pure recombinant proteins, either in the in vivo skin prick test or in vitro detection of the specific IgE in the serum samples of allergic subjects. This will be useful for the rational design of component-resolved diagnosis and allergen immunotherapy for the allergy mediated by the bites of black flies.
    Matched MeSH terms: Immunoglobulin E/immunology
  8. Woon FC, Chin YS, Ismail IH, Abdul Latiff AH, Batterham M, Chan YM, et al.
    Nutrients, 2020 Aug 12;12(8).
    PMID: 32806653 DOI: 10.3390/nu12082418
    Allergic diseases are the most common chronic illness in childhood. Findings from developed countries have reported associations between Vitamin D levels during pregnancy and offspring allergy risk. This prospective cohort study aimed to determine the associations between maternal Vitamin D levels during late pregnancy and allergic diseases in Malaysian infants during the first year of life. Serum 25(OH)D concentrations of 380 pregnant women in the third trimester were measured using a chemiluminescent immunoassay. Children's allergic outcomes were assessed at 3, 6, and 12 months based on parental reports. Specific IgE antibodies against food and inhalant allergens were measured in infants at 12 months of age. A total of 43.2% pregnant women were Vitamin D deficient (<30 nmol/L) and 56.8% were nondeficient (≥30 nmol/L). A total of 27.6% of the infants had eczema, 6.1% had wheeze, 27.4% had food sensitization, 10.8% had inhalant allergen sensitization, and 3.8% had IgE-mediated food allergy during the first year of life. Compared with the nondeficient group, maternal Vitamin D deficiency in late pregnancy was not associated with any allergic outcomes after adjustment for potential confounding factors. In conclusion, the present study does not support an association between maternal Vitamin D levels in late pregnancy and allergic outcomes during the first year of life.
    Matched MeSH terms: Immunoglobulin E/immunology
  9. Rosmilah M, Shahnaz M, Zailatul HM, Noormalin A, Normilah I
    Trop Biomed, 2012 Sep;29(3):467-78.
    PMID: 23018510
    Crab is an important source of food allergen. Tropomyosin represents the main crab allergen and is responsible for IgE cross-reactivity between various species of crustaceans. Recently, other new crab allergens including arginine kinase have been identified. However, information on allergens of the local Portunidcrab is not available. Thus, the aim of this study was to identify the major allergens of Portunus pelagicus (blue swimming crab) using the allergenomics approach. Raw and cooked extracts of the crab were prepared from the crab meat. Protein profile and IgE binding pattern were demonstrated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting using sera from 30 patients with crab allergy. The major allergens of the crab were then identified by two-dimensional electrophoresis (2-DE), followed by mass spectrometry analysis of the peptide digests. The SDS-PAGE of raw extract revealed approximately 20 protein fractions over a wide molecular weight range, while cooked extract demonstrated fewer protein bands. The raw extract also demonstrated a higher number of IgE reactive bands than the cooked extract. A heat-resistant protein of 36 kDa has been identified as the major allergen in both raw and cooked extracts. In addition, a heat-sensitive protein of 41 kDa was also recognized as a major allergen in raw crab. The 2-DE gel profile of the raw extract demonstrated about >100 distinct proteins spots and immunoblotting of the 2-DE profile demonstrated at least 12 different major IgE reactive spots with molecular masses between 13 to 250 kDa and isoelectric point (pI) values ranging from 4.0 to 7.0. The 36 and 41 kDa proteins were identified as the crab tropomyosin and arginine kinase, respectively by mass spectrometry. Therefore, this study confirmed that tropomyosin and arginine kinase are the major allergens of the local Portunid crab, P. pelagicus.
    Matched MeSH terms: Immunoglobulin E/immunology
  10. Ahmad H, Balachandra D, Arifin N, Nolan TJ, Lok JB, Hayat Khan A, et al.
    Am J Trop Med Hyg, 2020 12;103(6):2288-2293.
    PMID: 32996454 DOI: 10.4269/ajtmh.20-0265
    Strongyloides stercoralis infection is prevalent worldwide and can cause lifelong infection in immunocompetent individuals, and potentially death in immunosuppressed patients. The diagnosis is hindered by the low sensitivity of microscopic examination, thus making serology an important complementary test to improve the detection rate. However, there were reports that some Strongyloides-infected individuals were negative with specific IgG and IgG4 assays, and other helminth infections were positive with commercial Strongyloides IgG-ELISAs. Thus, there is a need to develop better serodiagnostic methods for strongyloidiasis. We investigated the diagnostic potential of IgE-ELISAs using Strongyloides larval lysate. Sera from two groups infected with Strongyloides served as the positive reference, that is, 1) positive by commercial IgG-ELISAs and IgG4 rapid test, and stool samples positive by microscopy and/or PCR (group IA; n = 20); and 2) negative by IgG-ELISAs and IgG4 rapid test, but stool samples were PCR positive (group IB sera; n = 11). Sera from another two groups served as negative reference (controls), that is, 1) infected with other parasites (group II; n = 73) and 2) healthy donors (group III; n = 22). Results showed a 100% diagnostic sensitivity in detecting sera from groups IA and IB. The latter group of individuals probably had early infection because their IgG and IgG4 assays were negative. The optical density values of group IB sera were also significantly lower than those of group IA (P < 0.003). The IgE-ELISA was 100% specific when tested against sera from groups II and III. This study highlights the diagnostic potential of IgE-ELISA using larval lysate to detect strongyloidiasis, especially those with probable early infection.
    Matched MeSH terms: Immunoglobulin E/immunology*
  11. Misnan R, Salahudin Abd Aziz N, Mohamad Yadzir ZH, Bakhtiar F, Abdullah N, Murad S
    Iran J Allergy Asthma Immunol, 2016 Aug;15(4):309-316.
    PMID: 27921412
    Snail is one of the worst causes of food allergy. Thus, the aim of this study was to identify the major and minor allergens of the local marine snail (Cerithidea obtusa) and subsequently to investigate the impacts of heat treatment on the IgE-binding activity of snail allergens. Proteins from raw and heat-treated snails (boiled, roasted and fried) were extracted and then resolved by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Immunoblotting of all extracts were then performed using sera from patients with snail allergy. The results showed that the raw extract contains numerous protein bands between 12 to>250 kDa. Some thermostable proteins, predominantly the 33 and 42 kDa bands, remained detected in all cooked extracts with decreasing intensities from boiled to roasted to fried extracts, while the majority of thermolabile bands denatured after heating. Boiled snail had more protein bands compared to roasted and fried snails. Immunoblotting of raw extract demostrated 19 IgE-binding bands ranging from 15 to 240 kDa. The thermostable bands of 33 and 42 kDa and a thermolabile of 30 kDa band were identified as the major allergens of this snail. The cooked extracts yielded less allergenic bands. The boiled extract yielded approximately 14 IgE-binding bands with some smeared bands at high molecular weight regions. The roasted extract had lesser IgE-binding bands and the majority appeared as smears, while the IgE-reactivity in the fried extract was less visible and appeared as weak smears. This study indicated that both raw and cooked snails played a crucial role in snail allergenicity, as this species of snail contains both thermostable and thermolabile major allergens. The degree of snail allergenicity was revealed in the order: raw> boiled > roasted> fried. Thus, the results would facilitate in the development of effective diagnosis and management strategies of snail allergy in this country.
    Matched MeSH terms: Immunoglobulin E/immunology*
  12. Yadzir ZH, Misnan R, Abdullah N, Bakhtiar F, Arip M, Murad S
    Asian Pac J Trop Biomed, 2012 Jan;2(1):50-4.
    PMID: 23569834 DOI: 10.1016/S2221-1691(11)60189-5
    OBJECTIVE: To characterize the major allergens of Macrobrachium rosenbergii (giant freshwater prawn).

    METHODS: Raw and cooked extracts of the giant freshwater prawn were prepared. The IgE reactivity pattern was identified by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting technique with the sera of 20 skin prick test (SPT) positive patients. The major allergen identified was then characterized using the proteomics approach involving a combination of two-dimensional (2-DE) electrophoresis, mass spectrometry and bioinformatics tools.

    RESULTS: SDS-PAGE of the raw extract showed 23 protein bands (15-250 kDa) but those ranging from 40 to 100 kDa were not found in the cooked extract. From immunoblotting experiments, raw and cooked extracts demonstrated 11 and 5 IgE-binding proteins, respectively, with a molecular mass ranging from 15 to 155 kDa. A heat-resistant 36 kDa protein was identified as the major allergen of both extracts. In addition, a 42 kDa heat-sensitive protein was shown to be a major allergen of the raw extract. The 2-DE gel fractionated the prawn proteins to more than 50 different protein spots. Of these, 10 spots showed specific IgE reactivity with patients' sera. Matrix assisted laser desorption/ionization-time of flight (MALDI-TOF) analysis led to identification of 2 important allergens, tropomyosin and arginine kinase.

    CONCLUSIONS: It can be concluded that the availability of such allergens would help in component-based diagnosis and therapy of prawn allergies.

    Matched MeSH terms: Immunoglobulin E/immunology
  13. Yusoff NA, Hampton SM, Dickerson JW, Morgan JB
    J R Soc Promot Health, 2004 Mar;124(2):74-80.
    PMID: 15067979 DOI: 10.1177/146642400412400211
    Current understanding of the use of exclusion diets in the management of asthma in children is limited and controversial. The aim of this study was to examine the effects of excluding eggs and milk on the occurrence of symptoms in children with asthma and involved 22 children aged between three and 14 years clinically diagnosed as having mild to moderate disease. The investigation was single blind and prospective, and parents were given the option of volunteering to join the 'experiment' group, avoiding eggs, milk and their products for eight weeks, or the 'control' group, who consumed their customary food. Thirteen children were recruited to the experimental group and nine to the control group. A trained paediatrician at the beginning and end of the study period assessed the children. A seven-day assessment of food intake was made before, during and immediately after the period of dietary intervention in both groups. A blood sample was taken from each child for determination of food specific antibodies and in those children who could do so, the peak expiratory flow rate (PEFR) was measured. Based on the recommended nutrient intake (RNI), the mean percentage energy intake of the children in the experimental group was significantly lower (p < 0.05) in the experimental group. After the eight-week study period and compared with baseline values, the mean serum anti-ovalbumin IgG and anti-beta lactoglobulin IgG concentrations were statistically significantly reduced (p < 0.05) for both in the experimental group. In contrast, the values for anti-ovalbumin IgG in the control group were significantly increased and those for anti-beta lactoglobulin IgG were practically unchanged. The total IgE values were unchanged in both groups. Over the study period, the PEFR in those children in the experimental group able to perform the test was significantly increased, but no such change was noted in the children in the control group who could do the test. These results suggest that even over the short time period of eight weeks, an egg- and milk-free diet can reduce atopic symptoms and improve lung function in asthmatic children.
    Study site: Outpatient Department, Royal County Hospital and the Frimley Children’s Centre, United Kingdom
    Matched MeSH terms: Immunoglobulin E/immunology
  14. Joo Chan C, Richardo T, Lim RLH
    Int Rev Immunol, 2018;37(6):279-290.
    PMID: 30638084 DOI: 10.1080/08830185.2018.1509967
    Peanut allergy is a hypersensitivity reaction with symptoms varying from mild to severe anaphylaxis, tends to be lifelong and very few are able to outgrow this allergy. The prevalence of peanut allergy is highest among the Western countries and over the past decade, a 3.5 fold increase in prevalence of peanut allergy was reported among children in the United States. Increasing prevalence has also been observed among the Asian countries. As with other food allergies, peanut allergy reduces quality of life for the affected individuals and the social and economy burden of healthcare for peanut allergy is substantial. To date, there is no effective treatment for peanut allergy and disease management is by avoidance or relieve of symptoms via administration of epinephrine. Peanut allergy is a type-1 hypersensitivity reaction due to specific IgE production by activated T-helper type 2 (TH2) cells. Studies on various immunotherapy routes such as oral immunotherapy (OIT), sublingual immunotherapy and epicutaneous immunotherapy trials using peanut have shown the ability to induce desensitisation, shifting the allergen-specific cytokine production away from a TH2 respond. In the recent years, lactic acid bacteria probiotics have been reported to down-regulate allergy due to its inherent immunomodulatory properties. Wild-type probiotic in combination with peanut proteins or recombinant probiotics harbouring peanut allergens have been explored for OIT due to its ability to down-regulate allergen-specific-IgE production and the TH2 responses, while increasing the beneficiary population of TH1 regulatory T cells (Treg). This review discusses the current strategies in immunotherapy for peanut allergy.
    Matched MeSH terms: Immunoglobulin E/immunology
  15. Chan CJ, Yong YS, Song AAL, Abdul Rahim R, In LLA, Lim RLH
    J Appl Microbiol, 2020 Mar;128(3):862-874.
    PMID: 31758869 DOI: 10.1111/jam.14524
    AIM: To study the prophylactic effect of recombinant Lactococcus lactis (rLl) harbouring Ara h 2.02 peanut allergen, in sensitized and challenged mice.

    METHODS AND RESULTS: Ara h 2.02 cDNA was cloned into pNZ8048 for heterologous expression in L. lactis. The purified recombinant allergen showed IgE binding comparable with native Ara h 2. Balb/c mice were fed with either recombinant (rLl), nonrecombinant L. lactis (Ll) or NaHCO3 (Sham) prior to sensitization and challenged with rAra h 2.02, whereas the baseline group was only fed with Ll. Allergen-specific immunoglobulin and splenocyte cytokines responses were determined for each mouse. Mice fed with either Ll or rLl showed significant alleviation of IgE and IgG1 compared to the Sham group. Despite no significant decrease in Th2 (IL-4, IL-13, IL-6) or increase in Th1 (IFN-γ) cytokines, both groups showed lower IL-10 level, while the IL-4 : IFN-γ ratio was significantly lower for rLl compared to Ll group.

    CONCLUSIONS: Oral administration of rLl harbouring Ara h 2.02 demonstrated alleviation of Th2-associated responses in allergen-challenged mice and a possible added allergen-specific prophylactic effect.

    SIGNIFICANCE AND IMPACT OF THE STUDY: Ara h 2.02 coupled with the intrinsic properties of probiotic L. lactis as a delivery vehicle can be explored for the development of a commercially scalable vaccine.

    Matched MeSH terms: Immunoglobulin E/immunology
  16. Lew MH, Lim RL
    Appl Microbiol Biotechnol, 2016 Jan;100(2):661-71.
    PMID: 26411458 DOI: 10.1007/s00253-015-6953-y
    Current diagnostic tools for peanut allergy using crude peanut extract showed low predictive value and reduced specificity for detection of peanut allergen-specific immunoglobulin E (IgE). The Ara h 2.02, an isoform of the major peanut allergen Ara h 2, contains three IgE epitope recognition sequence of 'DPYSPS' and may be a better reagent for component resolve diagnosis. This research aimed to generate a codon-optimised Ara h 2.02 gene for heterologous expression in Escherichia coli and allergenicity study of this recombinant protein. The codon-optimised gene was generated by PCR using overlapping primers and cloned into the pET-28a (+) expression vector. Moderate expression of a 22.5 kDa 6xhistidine-tagged recombinant Ara h 2.02 protein (6xHis-rAra h 2.02) in BL21 (DE3) host cells was observed upon induction with 1 mM isopropyl β-D-1-thiogalactopyranoside (IPTG). The insoluble recombinant protein was purified under denaturing condition using nickel-nitrilotriacetic acid (Ni-NTA) affinity chromatography and refolded by dialysis in decreasing urea concentration, amounting to a yield of 74 mg/l of expression culture. Matrix-assisted laser desorption/ionisation time-of-flight (MALDI-TOF) and immunoblot analysis confirmed the production of the recombinant 6xHis-rAra h 2.02. The refolded recombinant 6xHis-rAra h 2.02, with or without adjuvant, was able to elicit comparable level of allergen-specific IgE and IgG1 in sensitised Balb/c mice. In addition, the specific IgE antibodies raised against the recombinant protein were able to recognise the native Ara h 2 protein, demonstrating its allergenicity and potential as a reagent for diagnosis and therapeutic study.
    Matched MeSH terms: Immunoglobulin E/immunology
  17. Goh DL, Chua KY, Chew FT, Liang RC, Seow TK, Ou KL, et al.
    J Allergy Clin Immunol, 2001 Jun;107(6):1082-7.
    PMID: 11398089
    BACKGROUND: We have previously described anaphylaxis induced by edible bird's nest (BN) and demonstrated that this condition is IgE mediated.

    OBJECTIVES: This study aimed at describing the immunochemical properties of the BN allergens. Comparative studies between 3 commercially available sources (according to the country of origin) of BN were also made.

    METHODS: Crude extracts of commercially available processed BN from Sarawak (Malaysia), Thailand, and Indonesia and fresh unprocessed BN from the caves of Sarawak were obtained by means of aqueous extraction. Specific IgE toward these sources were determined by using fluorescence allergosorbent tests (FASTs). Cross-reactivity studies between the 3 sources of commercially available processed BN were carried out by means of FAST inhibition. Immunochemical characterization by means of IgE immunoblot, periodate treatment, and heat stability studies were carried out on fresh unprocessed BN from Sarawak.

    RESULTS: Serum from allergic patients showed differences in IgE binding to the 3 sources of commercially available BN, with the highest levels of specific IgE recorded with the Sarawak source (P

    Matched MeSH terms: Immunoglobulin E/immunology
  18. Rosmilah M, Shahnaz M, Meinir J, Masita A, Noormalin A, Jamaluddin M
    Int Arch Allergy Immunol, 2013;162(4):299-309.
    PMID: 24193115 DOI: 10.1159/000354544
    The longtail tuna (Thunnus tonggol) is widely consumed in Asia. Parvalbumin, the main major allergen of fish, has been well identified in multiple fish species, yet little is known about the allergenic proteins in T. tonggol. Thus, the aim of this study was to characterize the major allergens of T. tonggol using a proteomics approach.
    Matched MeSH terms: Immunoglobulin E/immunology
  19. Lee YZ, Shaari K, Cheema MS, Tham CL, Sulaiman MR, Israf DA
    Eur J Pharmacol, 2017 Feb 15;797:53-64.
    PMID: 28089919 DOI: 10.1016/j.ejphar.2017.01.011
    2,4,6-Trihydroxy-3-geranyl acetophenone (tHGA) is a synthetic compound that is naturally found in Melicope ptelefolia. We had previously demonstrated that parenteral administration of tHGA reduces pulmonary inflammation in OVA-sensitized mice. In this study, we evaluated the effect of orally administered tHGA upon airway remodeling in a murine model of chronic asthma. Female BALB/C mice were sensitized intraperitoneally with ovalbumin (OVA) on day 0, 7 and 14, followed by aerosolized 1% OVA 3 times per week for 6 weeks. Control groups were sensitized with saline. OVA sensitized animals were either treated orally with vehicle (saline with 1% DMSO and Tween 80), tHGA (80, 40, 20mg/kg) or zileuton (30mg/kg) 1h prior to each aerosolized OVA sensitization. On day 61, mice underwent methacholine challenge to determine airway hyperresponsiveness prior to collection of bronchoalveolar lavage (BAL) fluid and lung samples. BAL fluid inflammatory cell counts and cytokine concentrations were evaluated while histological analysis and extracellular matrix protein concentrations were determined on collected lung samples. Oral tHGA treatment attenuated airway hyperresponsiveness and inhibited airway remodeling in a dose-dependent fashion. tHGA's effect on airway remodeling could be attributed to the reduction of inflammatory cell infiltration and decreased expression of cytokines associated with airway remodeling. Oral administration of tHGA attenuates airway hyperresponsiveness and remodeling in OVA-induced BALB/c mice. tHGA is an interesting compound that should be evaluated further for its possible role as an alternative non-steroidal pharmacological approach in the management of asthma.
    Matched MeSH terms: Immunoglobulin E/immunology
  20. Ashley SE, Tan HT, Peters R, Allen KJ, Vuillermin P, Dharmage SC, et al.
    Clin Exp Allergy, 2017 Aug;47(8):1032-1037.
    PMID: 28544327 DOI: 10.1111/cea.12942
    BACKGROUND: Food allergies pose a considerable world-wide public health burden with incidence as high as one in ten in 12-month-old infants. Few food allergy genetic risk variants have yet been identified. The Th2 immune gene IL13 is a highly plausible genetic candidate as it is central to the initiation of IgE class switching in B cells.

    OBJECTIVE: Here, we sought to investigate whether genetic polymorphisms at IL13 are associated with the development of challenge-proven IgE-mediated food allergy.

    METHOD: We genotyped nine IL13 "tag" single nucleotide polymorphisms (tag SNPs) in 367 challenge-proven food allergic cases, 199 food-sensitized tolerant cases and 156 non-food allergic controls from the HealthNuts study. 12-month-old infants were phenotyped using open oral food challenges. SNPs were tested using Cochran-Mantel-Haenszel test adjusted for ancestry strata. A replication study was conducted in an independent, co-located sample of four paediatric cohorts consisting of 203 food allergic cases and 330 non-food allergic controls. Replication sample phenotypes were defined by clinical history of reactivity, 95% PPV or challenge, and IL13 genotyping was performed.

    RESULTS: IL13 rs1295686 was associated with challenge-proven food allergy in the discovery sample (P=.003; OR=1.75; CI=1.20-2.53). This association was also detected in the replication sample (P=.03, OR=1.37, CI=1.03-1.82) and further supported by a meta-analysis (P=.0006, OR=1.50). However, we cannot rule out an association with food sensitization. Carriage of the rs1295686 variant A allele was also associated with elevated total plasma IgE.

    CONCLUSIONS AND CLINICAL RELAVANCE: We show for the first time, in two independent cohorts, that IL13 polymorphism rs1295686 (in complete linkage disequilibrium with functional variant rs20541) is associated with challenge-proven food allergy.

    Matched MeSH terms: Immunoglobulin E/immunology*
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