ASCIA-P19: DISCOVERY OF 7S AND 11S GLOBULINS AS PUTATIVE ALLERGENS IN MACADAMIA NUT BY COMBINING ALLERGENOMICS AND PATIENT SERUM IGE BINDING

Cord basophil preparations from 53 term neonates were studied for various factors affecting immediate hypersensitivity reactions including: basophil IgE receptor density and histamine releasability following incubation with calcium ionophore A23187, zymosan-activated serum (C5a), and anti-IgE. Basophil histamine content (geometric mean, 0.4 pg/basophil, with content in 14/28 cord blood samples below 0.2 pg/cell) is considerably below that of atopic and nonatopic individuals (geometric mean, 2.3 pg/basophil). Histamine release is normal with both A23187 (range 33% to 88%) and C5a (range 11% to 58%). Normal release with anti-IgE was shown in five of nine cord blood samples (range 13% of 52%), but four of five cell preparations required IgE preincubation. Indirect evidence indicates that basophils from newborns contain less than 30,000 total IgE receptors /cell. IgE-mediated histamine release in basophils from newborns is minimized by suboptimal IgE binding. Optimal IgE binding is not favored in basophils from neonates because of low serum IgE and low IgE receptor density. Serum IgE and IgE receptors increase to a variable degree as the child grows older and may determine the clinical onset of allergic disease.

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Characterization and Antibacterial Activity of 7S and 11S Globulins Isolated from Cowpea Seed Protein

Molecules ◽

10.3390/molecules24061082 ◽

2019 ◽

Vol 24 (6) ◽

pp. 1082 ◽

Cited By ~ 12

Author(s):

Seham Abdel-Shafi ◽

Abdul-Raouf Al-Mohammadi ◽

Ali Osman ◽

Gamal Enan ◽

Samar Abdel-Hameid ◽

...

Keyword(s):

Antibacterial Activity ◽

Molecular Mass ◽

Klebsiella Pneumonia ◽

Listeria Ivanovii ◽

Sds Page ◽

Cell Components ◽

Cowpea Seed ◽

11S Globulin ◽

7S And 11S Globulins ◽

11S Globulins

The present work was carried out to determine the characteristics and antibacterial activity of 7S and 11S globulins isolated from cowpea seed (Vigna unguiculata (L.) Walp.). The molecular mass of 7S globulin was demonstrated by SDS-PAGE bands to be of about 132, 129 and 95 kDa corresponding the α/, α and β subunits. The molecular mass of 11S globulin was demonstrated by SDS-PAGE bands to be existed between 28 and 52 kDa corresponding the basic and acidic subunits. The minimum inhibitory concentrations MICs of 7S and 11S globulins isolated from cowpea seed were determined against Gram positive bacteria viz: Listeria monocytogenes LMG 10470, Listeria ivanovii FLB 12, Staphylococcus aureus ATCC 25923 and Streptococcus pyogenes ATCC 19615, and Gram negative bacteria such as Klebsiella pneumonia ATCC 43816, Pseudomonas aeruginosa ATCC 26853, Escherichia coli ATCC 25922 and Salmonella ATCC 14028 using disc diffusion assay; they were showed to be in the range 10 to 200 µg/mL. Transmission electron microscope (TEM) examination of the protein-treated bacteria showed the antibacterial action of 11S globulin against S. typhimurium and P. aeruginosa was manifested by signs of cellular deformation, partial and complete lysis of cell components. Adding 11S globulin at both concentrations 50 and 100 µg/g to minced meat showed considerable decreases in bacterial counts of viable bacteria, psychrotrophs and coliforms compared to controls during 15 days storage at 4 °C, reflecting a promising perspective to use such globulin as a meat bio-preservative.

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IgE-binding to vicilin-like antimicrobial peptides is associated with systemic reactions to macadamia nut

Clinical and Translational Allergy ◽

10.1186/s13601-020-00364-5 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Anna M. Ehlers ◽

Stefanie Rohwer ◽

Henny G. Otten ◽

Bettina Brix ◽

Thuy-My Le ◽

...

Keyword(s):

Mass Spectrometry ◽

Antimicrobial Peptides ◽

Dietary Habits ◽

Allergic Reactions ◽

Ige Binding ◽

Tree Nut ◽

Systemic Reactions ◽

Macadamia Nut ◽

Tree Nut Allergy ◽

Industrialised Countries

Abstract Background Macadamia nut can induce fatal allergic reactions and changes in dietary habits will raise their consumption in industrialised countries. Until now diagnosis of macadamia nut allergy by sIgE solely relies on the macadamia nut extract, but single components are lacking. Methods Macadamia nut proteins recognised by IgE from 2 macadamia nut extract positive sera were identified by mass spectrometry (vicilin-like antimicrobial peptides: VLAP). Sensitisation to macadamia nut extract and heterologously expressed isoform VLAP-2–3 was evaluated in 82 nut allergic (NA) and 27 tolerant (NT) patients (no tree nut allergy reported) comprehending 10 macadamia nut allergic (MA) and 18 explicitly reported macadamia nut tolerant patients (MT), using line blots. Co-sensitisation to additional VLAP isoforms and other vicilins was evaluated in 8 MA, 12 MT and 14 NA patients sensitised to VLAP-2–3. Functional properties were determined by indirect basophil activation. Results Even though proteins recognised by IgE were identified as VLAP-2–1, 2–2 and 2–3, only peptides specifically belonging to VLAP-2–3 were detected by mass spectrometry. The macadamia nut extract was recognised by 33% of NA patients (27/82) including 3 MA patients and 26% of NT patients (7/27, 3 MT). Similarly, 29% of NA (24/82) patients showed partly strong sIgE-binding to VLAP-2–3 including 3 MA patients with systemic reactions to macadamia nut. Contrary, VLAP-2–3 was recognised by only 2 NT (1 MT) patients (7%) with very low sIgE titres. Simultaneous recognition of the isoforms VLAP-2–1 and 2–2 was observed in all patients positive for VLAP-2–3 with partly reduced sIgE titres in 59% of these patients. Additionally, all three VLAP isoforms were able to repeatedly induce BAT reactivity upon sensitisation with a MA serum. Conclusion VLAP proteins are the first described macadamia nut components with serological and functional allergenic properties and they are associated with systemic reactions to macadamia nut.

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Elevation of IgE-binding factors in serum of patients with B cell- derived chronic lymphocytic leukemia

Blood ◽

10.1182/blood.v71.1.94.94 ◽

1988 ◽

Vol 71 (1) ◽

pp. 94-98 ◽

Cited By ~ 86

Author(s):

M Sarfati ◽

D Bron ◽

L Lagneaux ◽

C Fonteyn ◽

H Frost ◽

...

Keyword(s):

B Cells ◽

Chronic Lymphocytic Leukemia ◽

High Performance ◽

Solid Phase ◽

Intermediate Stage ◽

Lymphocytic Leukemia ◽

Serum Ige ◽

Ige Binding ◽

Ige Receptors

Abstract One hundred nineteen sera from patients with various lymphoproliferative diseases and normal sera were tested by a solid- phase radioimmunoassay (RIA) for their content in IgE-binding factor (IgE-BF), a soluble glycoprotein binding to IgE and derived from low- affinity IgE receptors (Fc epsilon R). Fc epsilon R, recently identified as CD23, are known to be expressed on the surface of B cells at the intermediate stage of differentiation. The results indicate that in all cases of chronic lymphocytic leukemia (CLL) tested (n = 40), IgE- BF levels (45 to 8,656 U/mL) were 3-fold to 500-fold higher than in 24 controls (15.5 +/- 2 U/mL). With a few exceptions, serum IgE-BF levels could differentiate patients with CLL from those with other leukemias or lymphomas. In vitro studies indicated that B lymphocytes isolated from CLL patients produced 8 to 50 times more IgE-BF than did normal B cells (P less than 0.001). IgE-BF level was correlated with the Rai stage of the disease (P = 0.002) and the lymphocyte count (P = 0.041). IgE-BF was purified to homogeneity from one CLL serum sample by a combination of affinity chromatography and reverse-phase high- performance liquid chromatography (HPLC). this IgE-BF proved identical to IgE-BF isolated from the culture supernatant of RPMI 8866 cells, a B lymphoblastoid cell line bearing Fc epsilon R and secreting IgE-BF. Indeed, the two molecules had the same mol wt (25 to 27 kd), the same isoelectric point, and the same tryptic map. We suggest that determination of serum IgE-BF might prove useful for clinical monitoring of CLL.

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