BACKGROUND: The purpose of this study was to find out the cause of discrepancy between various automated immunoassays for 25-hydroxy-vitamin D (25-[OH]D). METHODS: National Institute of Standards & Technology Standard Reference Material (SRM) 972a is SRM for 25-(OH)D and consists of 4 vials of frozen serum with different concentrations of 25-(OH)D. Each concentration was measured 6 times in 3 different immunoassays: ADVIA Vitamin D Total assay (Siemens Healthcare, Erlangen, Germany), ARCHITECT 25-(OH)D (Abbott Laboratories, Abbott Park, IL, USA), and COBAS Vitamin D Total assay (Roche Diagnostics, Basel, Switzerland). RESULTS: When using the certified reference values of SRM 972a as it is, discarding the cross-reactivity of each immunoassay, for ADVIA, the coefficient of determination (R2) as a score of regression analysis was 0.8995 and maximal difference between measured value and certified reference value was 3.6 ng/mL in level 3. The R2 and maximal differences of ARCHITECT were 0.5377 and 6.9 ng/mL, respectively, in level 4. Those of COBAS were 0.3674 and 22.3 ng/mL, respectively, in level 4. When considering cross-reactivities of each immunoassays to various 25-(OH)D metabolites, the ADVIA had R2 and maximal difference of 0.9254 and 3.3 ng/mL, respectively, in level 3. For ARCHITECT, the R2 and maximal differences were 0.7602 and 5.1 ng/mL, respectively, in level 1. Those of COBAS were 0.9284 and 4.9 ng/mL, respectively, in level 1. CONCLUSIONS: The cause of discrepancies between vitamin D immunoassays was mainly on the difference in cross-reactivities to various vitamin D metabolites. The discrepancies can be considerably decreased by considering cross-reactivities of each immunoassay.
Cross Reactions ; Delivery of Health Care ; Immunoassay* ; Reference Values ; Vitamin D* ; Vitamins*

Antihistamines (histamine receptor antagonists) are widely prescribed medicines in the treatment of allergic disorders, especially the symptoms of hypersensitivity reactions, mainly blocking the activity of vasoactive amines to their receptors. Drug adverse reactions such as sleepiness and dry mouth are frequently encountered. However, drug hypersensitivity provoking itchy hives by antihistamines were rarely reported. A 41-year-old female patient visited allergy clinic for generalized itchy hives from time to time, which had been aggravated 3 months before. Whenever she was exposed to antihistamines for treatment, she felt her hives got immediately full-blown. As a screening, she was tested with various antihistamines on her skin, then skin test-negative antihistamines were orally administered. Finally we failed to choose a safe antihistamine for the treatment of her symptoms. We report a case of drug hypersensitivity to various antihistamines with cross-reactions in a patient with chronic urticaria.
Adult ; Amines ; Cross Reactions ; Drug Hypersensitivity* ; Female ; Histamine Antagonists* ; Humans ; Hypersensitivity ; Mass Screening ; Mouth ; Skin ; Urticaria

The intradermal (ID) test has been widely used in Korea and several reports about the results of the ID test are known. We examined the egg of Clonorchis sinensis (C.s.) by ID test in 443, stool's egg-counting technique in 79 and direct smear (cellophane thick smear technique) in 1204 subjects. The results are as follows: 1. The positive rate of C.s. was 3.8% out of 1304 persons. 2. The sensitivity of ID test was 82.1% out of 39 persons and the specificity was 64.6% out of 404 persons. 3. The false positive of ID test was 35.4% out of 404 persons and, the false negative was 17.9% out of 39 persons. Intradermal test is a rapid, sensitive and useful supplementary diagnostic tool for the detection of Clonorchiasis infection and must be used as screening test with direct smear of stool but cross reaction with other helminth infections and moderate false reaction are the main disadvantages in its practical application.
Clonorchiasis ; Clonorchis sinensis* ; Cross Reactions ; Helminths ; Humans ; Intradermal Tests* ; Korea ; Mass Screening ; Ovum ; Sensitivity and Specificity

Mugwort and ragweed pollens have been considered as important respiratory allergens in Korea. These two pollens are abundant in the air of Seoul from August through October. Many ragweed-sensitive patients have shown concurrent sensitivities to mugwort pollen. However the antigenic relationship between these two pollens has not been clarified. To observe the cross-reactivity between them, we developed polyclonal anti-mugwort and anti-ragweed antibodies by immunization on New Zealand white rabbits, and performed crossed immunoelectrophoresis(CIE) with two pollen extracts. Five precipitation lines were formed by mugwort and anti-mugwort antibody. One precipitation line was formed by ragweed and anti-ragweed antibody. There was no reaction from mugwort and anti-ragweed antibody, and from ragweed and anti-mugwort antibody. These results indicate that there is no cross-antigenicity between mugwort and ragweed pollens.
Animal ; Antibodies/immunology ; Cross Reactions ; Immunoelectrophoresis, Two-Dimensional ; Pollen/*immunology ; Rabbits

OBJECTIVETo develop a time-resolved fluoroimmunoassay (TRFIA) for detection of pertussis toxin (PT) S1 subunit for quality control of human PT vaccine.

METHODSA double antibody sandwich one-step method was used to establish the TRFIA for detecting PT S1 subunit in the vaccine.

RESULTSThe sensitivity of c peptide analysis reached 2.5 ng/ml without cross-reactions with other antigens. This assay could be used in detecting S1 subunit in the vaccine.

CONCLUSIONThe TRFIA for detecting PT S1 subunit is simple, sensitive and rapid for quality control of the PT vaccine.

Cross Reactions ; Fluoroimmunoassay ; methods ; Pertussis Toxin ; analysis ; Pertussis Vaccine ; chemistry ; standards ; Quality Control ; Sensitivity and Specificity

After search at hematopoietic stem cell banks for transplant donors, there may be several donors matched with given standards. To determine the most appropriate donor for a specific patient, the potential donors were analyzed and compared by three methods. The first is cross-reactive group (CREG) antigens, which defined as the public antigens that shared specific serological reaction patterns. The second is residue match theory, which concerned the three residues oriented upward toward the T-cell receptor. The third is comparing HLA three-dimensional structure models. The results of the three methods were not completely accorded in our case. However, some less matched donors could be excluded from the candidates and the range of selection was further reduced. It is concluded that combined application of three methods would contribute in selecting donor for hematopoietic stem cell transplantation in clinics.
Cross Reactions ; HLA Antigens ; immunology ; Hematopoietic Stem Cell Transplantation ; Histocompatibility Testing ; Humans ; Tissue Donors

Vaccination is the primary strategy for the prevention and control of pandemic influenza. Because influenza virus is highly variable across strains, universal influenza vaccines need to be developed to address this problem. This review describes the research progress in conserved epitopes of influenza virus, the advances in the research and development of universal influenza vaccines based on the relatively conserved sequences of NP, M2e, HA2, and headless HA, the mechanisms of cross-protection, and the methods to improve cross-protection.
Animals ; Cross Reactions ; Humans ; Orthomyxoviridae ; immunology ; Species Specificity ; Viral Proteins ; immunology ; Viral Vaccines ; genetics ; immunology

OBJECTIVETo prepare rabbit monoclonal antibody (RabMab) against guanosine 3', 5'-cyclic monophosphate (cGMP) and to develop a competitive ELISA for the detection of cGMP.

METHODSNew Zealand white rabbits were immunized with synthesized cGMP-keyhole limpet hemoeyanin (cGMP-KLH) to prepared a RabMAb with monoclonal antibody technique of Epitomics. A competitive ELISA kit was produced with cGMP RabMAb. The specificity, the precision and the recoveries of the method were determined.

RESULTSThe RabMAb with high sensitivity towards cGMP were prepared with an antibody timer of 3.1 ng/mL and 50% inhibitive concentration (IC50) of 12.57 ng/mL. The cGMP RabMAb had 33% cross-reactivity to inosine 3', 5'-cyclic monophosphate (cIMP) and little or no cross-reactivity to other compounds. A competitive ELISA was developed for detection of cGMP. The range of detection was 0~120 ng/mL with a minimal limit of 1.95 ng/mL. The recovery of assay was 89%~103%. The inter-assay and intra-assay coefficient variations were below 11.68% and 13.85%, respectively.

CONCLUSIONThe RabMab against cGMP with high affinity and high specificity has been generated successfully, and a competitive ELISA for detection of cGMP has been developed with the prepared cGMP RabMAb.

Animals ; Antibodies, Monoclonal ; biosynthesis ; Antibody Specificity ; Cross Reactions ; Cyclic GMP ; immunology ; Enzyme-Linked Immunosorbent Assay ; Rabbits

AIDS Vaccines ; immunology ; China ; Cross Reactions ; Genetic Vectors ; HIV-1 ; immunology ; Humans ; Immunity, Innate ; Immunity, Mucosal

Food allergy is phenotypically an extremely heterogeneous group of diseases affecting multiple organs, sometimes in an isolated way, sometimes simultaneously, with the severity of reactions ranging from mild and local to full-blown anaphylaxis. Mechanistically, it is defined as a Th2-driven immune disorder in which food-specific IgE antibodies are at the basis of immediate-type adverse reactions. The sites of sensitization and symptoms do not necessarily overlap. Food allergy, which is the theme of this paper, is often confused with other adverse reactions to food of both animmune (e.g., celiac disease) and non-immune (e.g., lactose intolerance) nature. To reliably diagnose food allergy, a careful history (immediate-type reactions) needs to be complemented with demonstration of specific IgE (immune mechanism) and confirmed by an oral challenge. Co-factors such as exercise, medication, and alcohol may help trigger food allergy and further complicate accurate diagnosis. Where food extract-based diagnostic tests are poorly correlated to symptom severity, new generation molecular diagnostics that measure IgE against individual food allergens provide clinicians and patients with more reliable symptom severity risk profiles. Molecular diagnostics also support establishing whether food sensitization originates directly from exposure to food or indirectly (cross-reactivity) from pollen sensitization. Epidemiological surveys have indicated that allergy to peach primarily originates from peach consumption in Europe, whereas in China it is the result of primary sensitization to mugwort pollen, in both cases mediated by an allergen molecule from the same family. Epidemiological surveys give insight into the etiology of food allergy, the size of the problem (prevalence), and the risk factors involved, which together support evidence-based strategies for prevention. Over the past decade, food allergy has increased in the affluent world. Economic growth and urbanization in upcoming economies are likewise expected to lead to increased prevalence of food allergies, sometimes to different foods due to dietary habits. Molecular allergology and biotechnology now offer the possibility to combat the increasing burden of food allergy by developing safe immunotherapies for food allergy, using hypoallergenic mutant recombinant molecules. The first clinical trials to evaluate such approaches are underway. Last but not least, the identification and clinical risk characterization of a more and more complete list of food allergens additionally provides the allergenicity risk assessment of genetically modified foods a firmer basis.
Allergens ; China ; Cross Reactions ; Food ; Food Hypersensitivity ; Humans ; Hypersensitivity ; Immunoglobulin E ; Immunotherapy ; Pollen ; Prevalence