Displaying all 4 publications

Abstract:
Sort:
  1. Mohamad Yadzir ZH, Bakhtiar F, Misnan R, Abdullah N, Leecyous B, Murad S
    Iran J Allergy Asthma Immunol, 2016 Apr;15(2):156-60.
    PMID: 27090369
    Allergy diagnosis needs to be improved in polysensitized patients due to the existence of possible confounding factors in this type of patients. Component resolved diagnosis (CRD) is a new concept in the investigation of polysensitized patients. The aim of this study was to evaluate if the utilization of ImmunoCAP ISAC improve the diagnosis of the polysensitized allergic rhinitis patients. Skin prick test (SPT) to 58 crude allergen extracts and CRD (ImmunoCAP ISAC) were carried out for 5 polysensitized allergic rhinitis patients. Two patients had a shellfish allergy and avoidance of shellfish was the only way to prevent an allergic reaction. In contrast, although the remaining three patients had low risk for shellfish allergy, but they were the best candidates for immunotherapy using mite extracts. CRD and particularly ImmunoCAP ISAC have proven to be a valuable diagnostic tool in polysensitized patients. ImmunoCAP ISAC helps refine the individual patient's sensitization profile and predict the potential risk of allergic reactions and improve the selection of patients for immunotherapy.
    Matched MeSH terms: Allergens/administration & dosage
  2. Turjanmaa K, Palosuo T, Alenius H, Leynadier F, Autegarden JE, André C, et al.
    Allergy, 1997 Jan;52(1):41-50.
    PMID: 9062628
    For the diagnosis of IgE-mediated (immediate) hypersensitivity to natural rubber latex (NRL), skin prick testing with extracts of latex gloves has been widely used, but such extracts are difficult to standardize. The present study aimed to produce on an industrial scale an NRL extract from freshly collected NRL and to evaluate, calibrate, and standardize the extract by both in vivo and in vitro testing. The source material, latex of the rubber tree, Hevea brasiliensis (clone RRIM 600), was frozen immediately after collection in Malaysia and shipped in dry ice to Stallergènes SA, France. Protein and allergen profiles were analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), immunoblotting, isoelectric focusing (IEF), crossed immunoelectrophoresis (CIE), and crossed radioimmunoelectrophoresis (CRIE). Allergen quantification was effected by RAST inhibition. The capacity of the preparation to elicit immediate hypersensitivity reactions in vivo was measured by skin prick testing in 46 latex-allergic patients and 76 nonallergic control subjects. SDS-PAGE and immunoblot profiles of the extract and an NRL standard (E8) provided by the US Food and Drug Administration were almost identical, disclosing several distinct IgE-binding proteins with apparent molecular weights of 14, 20, 27, 30, and 45 kDa, conforming to reported molecular weights of several significant NRL allergens. An arbitrary index of reactivity (IR) of 100 was assigned to the extract at 1:200 dilution (w/v), having a protein content of 22 micrograms/ml. Skin prick testing of latex-allergic patients and controls using the extract at 100 IR revealed 93% sensitivity, 100% specificity, 100% negative predictive value, and 96% positive predictive value. In conclusion, a skin prick test reagent for diagnosis of type I NRL allergy was successfully standardized. The reagent was demonstrated to contain most, if not all, of the currently known clinically significant NRL allergens, and it showed high sensitivity and specificity.
    Matched MeSH terms: Allergens/administration & dosage
  3. Chan SL, Ong TC, Gao YF, Tiong YS, Wang de Y, Chew FT, et al.
    J Immunol, 2008 Aug 15;181(4):2586-96.
    PMID: 18684949
    A high incidence of sensitization to Blomia tropicalis, the predominant house dust mite species in tropical regions, is strongly associated with allergic diseases in Singapore, Malaysia, and Brazil. IgE binding to the group 5 allergen, Blo t 5, is found to be the most prevalent among all B. tropicalis allergens. The NMR structure of Blo t 5 determined represents a novel helical bundle structure consisting of three antiparallel alpha-helices. Based on the structure and sequence alignment with other known group 5 dust mite allergens, surface-exposed charged residues have been identified for site-directed mutagenesis and IgE binding assays. Four charged residues, Glu76, Asp81, Glu86, and Glu91 at around the turn region connecting helices alpha2 and alpha3 have been identified to be involved in the IgE binding. Using overlapping peptides, we have confirmed that these charged residues are located on a major putative linear IgE epitope of Blo t 5 from residues 76-91 comprising the sequence ELKRTDLNILERFNYE. Triple and quadruple mutants have been generated and found to exhibit significantly lower IgE binding and reduced responses in skin prick tests. The mutants induced similar PBMC proliferation as the wild-type protein but with reduced Th2:Th1 cytokines ratio. Mass screening on a quadruple mutant showed a 40% reduction in IgE binding in 35 of 42 sera of atopic individuals. Findings in this study further stressed the importance of surface-charged residues on IgE binding and have implications in the cross-reactivity and use of Blo t 5 mutants as a hypoallergen for immunotherapy.
    Matched MeSH terms: Allergens/administration & dosage
  4. Leecyous B, Bakhtiar F, Tang MM, Yadzir ZHM, Abdullah N
    Allergol Immunopathol (Madr), 2020 06 09;48(6):626-632.
    PMID: 32532468 DOI: 10.1016/j.aller.2020.01.006
    INTRODUCTION: Basophil activation test (BAT) and immunoassays are the most widely used in vitro tests to diagnose IgE-mediated allergic reactions to penicillin. However, studies to determine if one test is interdependent from another are limited.

    OBJECTIVE: The present study aimed to measure the agreement between BAT and immunoassay in diagnosis of penicillin allergy.

    METHOD: BAT was performed using penicillin G (Pen G), penicillin V (Pen V), penicilloyl-polylysine (PPL), minor determinant mix (MDM), amoxicillin (Amx) and ampicillin (Amp) in 25 patients. Immunoassay of total IgE (tIgE) and specific IgE (sIgE) antibodies to Pen G, Pen V, Amx and Amp were quantified. Skin prick test (SPT) using PPL-MDM, Amx, Amp and Clavulanic acid were also performed.

    RESULTS: Minimal agreement was observed between BAT and immunoassay (k=0.25). Of two BAT-positive patients, one patient is positive to Amx (59.27%, SI=59) and Amp (82.32%, SI=82) but sIgE-negative to all drug tested. This patient is also SPT-positive to both drugs. Another patient is BAT-positive to Pen G (10.18%, SI=40), Pen V (25.07%, SI=100) and Amp (19.52%, SI=79). In sIgE immunoassay, four patients were sIgE-positive to at least one of the drugs tested. The sIgE level of three patients was between low and moderate and they were BAT-negative. One BAT-positive patient had a high level of sIgE antibodies (3.50-17.5kU/L) along with relatively high specific to total IgE ratio ≥0.002 (0.004-0.007).

    CONCLUSIONS: The agreement between BAT and immunoassay is minimal. Performing both tests provides little increase in the sensitivity of allergy diagnosis work-up for immediate reactions to penicillin.

    Matched MeSH terms: Allergens/administration & dosage*
Filters
Contact Us

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

External Links