Lack of cross-reactivity between the Bacillus thuringiensis derived protein Cry1F in maize grain and dust mite Der p7 protein with human sera positive for Der p7-IgE

Background: Global outbreaks caused by emerging or re-emerging arthropod-borne viruses (arboviruses) are becoming increasingly more common. These pathogens include the mosquito-borne viruses belonging to the Flavivirus and Alphavirus genera. These viruses often cause non-specific or asymptomatic infection, which can confound viral prevalence studies. In addition, many acute phase diagnostic tests rely on the detection of viral components such as RNA or antigen. Standard serological tests are often not reliable for diagnosis after seroconversion and convalescence due to cross-reactivity among flaviviruses. Methods: In order to contribute to development efforts for mosquito-borne serodiagnostics, we incubated 137 human sera on individual custom peptide arrays that consisted of over 866 unique peptides in quadruplicate. Our bioinformatics workflow to analyze these data incorporated machine learning, statistics, and B-cell epitope prediction. Results: Here we report the results of our peptide array data analysis, which revealed sets of peptides that have diagnostic potential for detecting past exposure to a subset of the tested human pathogens including Zika virus. These peptides were then confirmed using the well-established ELISA method. Conclusions: These array data, and the resulting peptides can be useful in diverse efforts including the development of new pan-flavivirus antibodies, more accurate epitope mapping, and vaccine development against these viral pathogens.

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Concentrations of 2-hydroxyoestrogens in human sera measured by a heterologous immunoassay with an 125I-labelled ligand

Acta Endocrinologica ◽

10.1530/acta.0.1000154 ◽

1982 ◽

Vol 100 (1) ◽

pp. 154-160 ◽

Cited By ~ 11

Author(s):

D. Berg ◽

F. Thaler ◽

E. Kuss

Keyword(s):

Standard Deviation ◽

Binding Sites ◽

Luteal Phase ◽

Healthy Subjects ◽

Cross Reactivity ◽

Follicular Phase ◽

Underlying Assumption ◽

Human Sera ◽

Tube Accuracy ◽

Serum Components

Abstract. A heterologous immunoassay for 2-hydroxyoestrogens1 has been established in which antibodies raised against 2-hydroxyoestradiol-17-succinyl-BSA serve as binding protein and 2-hydroxyoestrone-17-cmo-[125I]iodohistamine as radioligand. Lipophilic serum components competing for binding sites in this system were defined as 'total 2-hydroxyoestrogens'. The underlying assumption of specificity was supported by the pattern of cross-reactivity evaluated with structural related steroids and o-diphenols and by the fact, that an additional chromatography of the serum extracts preceding the competing reaction had little if any effect. Sensitivity: 2.8 ± 1 pg/tube; accuracy: Y = 0.91x + 2.2; r = 0.989; precision: 5.8% intra-assay; 6.5% inter-assay. The following concentrations ( ± standard deviation) were found in the sera of healthy subjects. Young men: 29 ± 5 pg/ml (n = 11); women follicular phase: 32 ± 8 pg/ml (n = 25); luteal phase: 53 ± 13 pg/ml (n = 23); postmenopausal women: 13 ± 4 pg/ml (n = 10); pregnant women 11th–20th week: 70 ± 16 mg/ml (n = 64); 36th–40th week: 240 ± 23 pg/ml (n = 40); newborn cord blood: 604 ± 43 pg/ml (n = 48).

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Antibodies in human sera to oncorna virus-like proteins from normal or leukemia marrow cell cultures.

Journal of Experimental Medicine ◽

10.1084/jem.144.5.1243 ◽

1976 ◽

Vol 144 (5) ◽

pp. 1243-1253 ◽

Cited By ~ 3

Author(s):

S Louie ◽

J E Curtis ◽

J E Till ◽

E A McCulloch

Keyword(s):

Lupus Erythematosus ◽

Competitive Inhibition ◽

Marrow Cell ◽

Leukemia Virus ◽

Polyacrylamide Gel Electrophoresis ◽

Cross Reactivity ◽

Antibody Activity ◽

Human Sera ◽

Blood Specimens ◽

Radioimmunoprecipitation Assay

Some human marrows in culture release particles with oncornavirus-like properties. This study was designed to examine the immunological properties of similar particles in human marrow culture supernates. Leukemic and nonleukemic marrows were cultured for 5-7 days in the presence of [14C]uridine and [3H]leucine or [3H]glucosamine. Labeled supernatant components banding in sucrose gradient densities of 1.20-1.24 g/ml were used as antigen in a double antibody immunoprecipitation assay. The assay was validated by end point titrations and competition with unlabeled antigen; purified myeloma proteins were used as negative controls. Cross-reactivity with mammalian oncornaviruses, as judged by competitive inhibition of precipitation by these viruses, was slight and at the border of the sensitivity of the method. Precipitated antigens analyzed by SDS polyacrylamide gel electrophoresis contained three distinct polypeptides of about 70,000, 45,000 and 30,000 mol wt; these comigrated with the gp 70, pg 45, and p 30 of a murine leukemia virus. Similar polypeptides were obtained from both leukemic and nonleukemic marrow culture supernates. As determined by the radioimmunoprecipitation assay, 32 of 45 leukemic sera (71%), 36 of 45 normal sera (80%), 15 of 19 sera from family contacts of leukemic patients (79%), 14 of 21 cord blood specimens (67%), and 21 of 23 sera (91%) from patients with systemic lupus erythematosus had detectable antibody activity.

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Immunological cross-reactivity of antibodies to a synthetic undecapeptide analogous to the amino terminal segment of carcinoembryonic antigen, with the intact protein and with human sera.

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.73.6.2123 ◽

1976 ◽

Vol 73 (6) ◽

pp. 2123-2127 ◽

Cited By ~ 17

Author(s):

R. Arnon ◽

M. Bustin ◽

E. Calef ◽

S. Chaitchik ◽

J. Haimovich ◽

...

Keyword(s):

Carcinoembryonic Antigen ◽

Cross Reactivity ◽

Terminal Segment ◽

Intact Protein ◽

Amino Terminal ◽

Human Sera

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Measurement of serum bone gla-protein (BGP) in humans with an ovine BGP-based radioimmunoassay

Clinical Chemistry ◽

10.1093/clinchem/36.9.1620 ◽

1990 ◽

Vol 36 (9) ◽

pp. 1620-1624 ◽

Cited By ~ 11

Author(s):

P Pastoureau ◽

P D Delmas

Keyword(s):

Amino Acids ◽

Primary Hyperparathyroidism ◽

Renal Osteodystrophy ◽

Clinical Investigation ◽

Gel Filtration ◽

Normal Subjects ◽

Conformational Epitope ◽

Cross Reactivity ◽

Bone Gla Protein ◽

Human Sera

Abstract Most RIAs of serum bone gla-protein (BGP; also called osteocalcin) used for clinical investigation are based on bovine BGP for standard, tracer, and immunogen because of the homology between bovine and human BGP. However, ovine BGP differs from human BGP by only five amino acids, being identical from residues 11 to 49, as compared with homology at residues 20-49 between bovine and human BGP. In screening various anti-ovine BGP polyclonal anti-sera we selected one (R310) that exhibits apparently complete cross-reactivity with human BGP, as assessed by dilutions of 13 human sera from normal subjects and from patients with bone disease. This RIA gave a 42% binding at a 10,000-fold final dilution, with intra- and interassay variations less than 7% and 11%, respectively. Gel-filtration chromatography of human serum showed a single immunoreactive peak. Synthetic fragments of human BGP 1-10, 7-19, 25-37, and 37-49 were not recognized by R310, suggesting that either a mid-molecule region or a conformational epitope was its target. Using this RIA, we determined that serum BGP increased with age in women (P less than 0.02), by a mean of 90% from ages 30 to 70 years. Serum BGP was also increased in patients with primary hyperparathyroidism, renal osteodystrophy, and Paget's disease. In contrast with the "normal" concentrations of BGP detected with an anti-bovine BGP antiserum (R102), serum BGP was increased in patients with postmenopausal osteoporosis as measured with the R310 ovine assay, suggesting a greater sensitivity for the latter assay.

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