We assessed the utility of an enzyme-linked immunosorbent assay (ELISA) for the detection of hantavirus-specific antibodies from sera of Oligoryzomys longicaudatus, the principal reservoir of Andes ...virus (ANDV), using an antigen previously developed for detection of antibodies to Sin Nombre virus (SNV) in sera from Peromyscus maniculatus. The assay uses a protein A/G horseradish peroxidase conjugate and can be performed in as little as 1.5 hours. Serum samples from Oligoryzomys longicaudatus collected in central-south Chile were used and the assay identified several that were antibody positive. This assay can be used for the rapid detection of antibodies to divergent hantaviruses from geographically and phylogenetically distant rodent species.
The aim of the present study was to investigate the sensitivity and specificity of anti-Sjögren's syndrome type B (SSB) antibodies for diagnosing systemic lupus erythematosus (SLE) and to understand ...the correlation between anti-SSB antibodies and the clinical manifestations of SLE. A line immunoassay (LIA) was used to detect the presence of serum anti-SSB antibodies in SLE patients. The clinical manifestations of the patients were recorded to enable their correlation with the serum anti-SSB antibodies to be analyzed. In 25.7% of the 74 SLE patients, the serum was positive for anti-SSB antibodies, whereas only 3.3% of the 30 control cases were positive. The specificity of anti-SSB antibodies for detecting SLE was 96.7%. In anti-SSB antibody-positive SLE patients, the incidence of cheek erythema, alopecia, serositis, secondary Sjögren's syndrome (sSS), leukocytopenia, elevated immunoglobulin (Ig)G and positive presence of anti-Sjögren's syndrome type A (SSA)60 or anti-SSA52 antibodies was higher than in the anti-SSB antibody-negative group (P<0.05). Anti-SSB antibodies are important for the diagnosis of SLE and are associated with cheek erythema, alopecia, serositis, sSS, leukocytopenia, the elevation of IgG and positive presence of anti-SSA60 or anti-SSA52 antibodies.
Abstract The diagnosis of chronic Chagas disease usually is made by detecting antibodies to Trypanosoma cruzi , the protozoan parasite that causes this illness. A highly sensitive and specific ...immunoblot assay developed by us showed a higher analytic sensitivity than the radioimmune precipitation assay, which is used widely as a confirmatory test.
The present study aimed to investigate the distribution of the octadecaneuropeptide (ODN) in the goldfish brain and to look for a possible effect of ODN on somatolactin (SL) release from pituitary ...cells. A discrete population of ODN‐immunoreactive neurones was localised in the lateral part of the nucleus lateralis tuberis. These neurones sent projections through the neurohypophyseal tract towards the neurohypophysis, and nerve fibres were seen in the close vicinity of SL‐producing cells in the pars intermedia. Incubation of cultured goldfish pituitary cells with graded concentrations of ODN (10−9–10−5 m) induced a dose‐dependent stimulation of SL‐β, but not SL‐α, release. ODN‐evoked SL release was blocked by the metabotrophic endozepine receptor antagonist cyclo1–8DLeu5OP but was not affected by the central‐type benzodiazepine receptor antagonist flumazenil. ODN‐induced SL release was suppressed by treatment with the phospholipase C (PLC) inhibitor U‐73122 but not with the protein kinase A (PKA) inhibitor H‐89. These results indicate that, in fish, ODN produced by hypothalamic neurones acts as a hypophysiotrophic neuropeptide stimulating SL release. The effect of ODN is mediated through a metabotrophic endozepine receptor positively coupled to the PLC/inositol 1,4,5‐trisphosphate/protein kinase C‐signalling pathway.
In human toxocariasis, there are few approaches using immunological markers for diagnosis and therapeutic assessment. An immunoblot (IB) assay using excretory-secretory Toxocara canis antigen was ...standardized for monitoring IgG, IgE and IgA antibodies in 27 children with toxocariasis (23 visceral, three mixed visceral and ocular, and one ocular form) for 22-116 months after chemotherapy. IB sensitivity was 100% for IgG antibodies to bands of molecular weight 29-38, 48-54, 95-116, 121-162, >205 kDa, 80.8% for IgE to 29-38, 48-54, 95-121, > 205 kDa, and 65.4% for IgA to 29-38, 48-54, 81-93 kDa. Candidates for diagnostic markers should be IgG antibodies to bands of low molecular weight (29-38 and 48-54 kDa). One group of patients presented the same antibody reactivity to all bands throughout the follow-up study; in the other group, antibodies decayed partially or completely to some or all bands, but these changes were not correlated with time after chemotherapy. Candidates for monitoring patients after chemotherapy may be IgG antibodies to > 205 kDa fractions, IgA to 29-38, 48-54, 81-93 kDa and IgE to 95-121 kDa. Further identification of antigen epitopes related to these markers will allow the development of sensitive and specific immunoassays for the diagnosis and therapeutic assessment of toxocariasis.
In Bushehr province of Iran, Avicennia marina trees have grown in Bordekhoon (Mond Protected Area) and Assaluyeh (Marine National Park of Nayband). Contrary to Bordekhoon, Assaluyeh is a ...petrochemical region with environmental pollution. This study was aimed to studying protein profiles, allergenic bands, ontogeny, structure and elemental composition of tectum of A. marina pollens in Assaluyeh and Bordekhoon. Pollens were collected from two regions and extracted in PBS, and protein profiles of pollens were determined by sulfate–polyacrylamide gel electrophoresis (SDS-PAGE). As an experimental model, 20 female 6–8-week-old Balb/C mice were divided into two groups. The mice of first and second groups were sensitized by Bordekhoon and Assaluyeh pollen extracts, respectively, and mice serum samples were used for immunoblotting. Pollen characteristics were studied using light and scanning electron microscopes. SDS-PAGE showed some differences between pollen protein profiles of two regions. Immunoblotting assay detected that pollens have two allergenic bands and the protein band at 100 KD is the common allergenic protein in two regions. Light microscopy revealed that the development of anther wall was basic type and some abnormalities were observed in microspores and pollens of Assaluyeh. Scanning electron microscopy studies showed that the apertures in considerable numbers of Assaluyeh pollens were closed. The comparison of elemental composition of pollen tectum between two regions showed that pollens of Assaluyeh have accumulated Cu on their tectum. Results obtained indicated that environmental pollution can affect protein profile, allergenic bands, structure and elemental composition of tectum of A. marina pollens.
The routine diagnosis of hepatitis C virus (HCV) infection is based on the detection of anti-HCV antibodies by two main methods (enzyme immunoassay EIA and chemiluminescence immunoassay CIA) but ...false-positives are a problem. We investigated three anti-HCV tests: two CIAs (Cobas® e 601 and Architect® i2000SR); and one EIA (Ortho® HCV 3.0). Two other anti-HCV tests were also performed as supplementary and confirmatory tests, respectively: a recombinant strip immunoblot assay (RIBA HCV 3.0 SIA) and a reverse transcriptase polymerase chain reaction-based assay for HCV-RNA. After discriminating the false-positive results, the true anti-HCV seropositivity rate in 7156 serum samples was 0.91%. The seropositivity and false-positive rates for the Cobas® e 601, Architect® i2000SR and Ortho® HCV 3.0 anti-HCV tests were 1.9% and 0.99%, 1.2% and 0.29%, and 0.87% and 0.01%, respectively. The mean level of HCV-RNA was 3399 × 103 IU/ml. Critical levels for false-positivity for HCV-RNA were a cut-off index of 200 for Cobas® e 601, a signal/cut-off (S/CO) of 5 for Architect® i2000SR and an S/CO of 1.2 for Ortho® HCV 3.0. Positive and negative results for the RIBA HCV 3.0 SIA assay all accorded with the HCV-RNA assay, except for 23 (17%) ‘indeterminate’ results, all of which were negative with the HCV-RNA assay. In conclusion, to eliminate doubts related to false-positive findings in the initial HCV screening tests, additional confirmatory HCV-RNA assay should be performed.
Objectives: (A) To examine the prevalence and demographic characteristics of hepatitis C virus (HCV) infection among childbearing women in Scotland; and (B) to determine the extent of maternal HCV ...infection diagnosed prior to birth. Methods: (A) Residual dried blood spot samples from routine neonatal screening, collected throughout Scotland during March-October 2000, were unlinked from identifiers and tested anonymously for HCV antibodies; and (B) electronic record linkage of Scotland’s databases of births and diagnosed HCV infections was performed. Results: (A) Of 30 259 samples, 121 were enzyme linked immunosorbent assay repeat reactive and 88 of these were confirmed as anti-HCV positive in the recombinant immunoblot assay, representing a seroprevalence of 0.29–0.40%. HCV seroprevalence was high among 25–29 year olds (0.4–0.57%), in high deprivation areas (0.92–1.07%), and in Greater Glasgow (0.83–0.96%) and Grampian (0.38–0.62%). Adjusted relative risk for HCV infection was highest among residents in high deprivation areas of Glasgow (7.2 (95% confidence interval 2.0–25.5)). (B) Of 121 HCV infections found among women at delivery, 24% and 46% were estimated to have been diagnosed prior to pregnancy and birth, respectively. Conclusions: HCV prevalence among Scottish childbearing women is consistent with that expected from injecting drug use. Based on reported rates of mother to child transmission, 8–11 paediatric infections are expected per annum. Diagnosis in only 24% of infected women prior to pregnancy indicates the extent to which HCV goes unrecognised in the injecting community. The current HCV screening approach—to test only those with a history of injecting drug use (or other risk factors for infection)—identifies approximately a quarter of previously undetected infections among pregnant women.
Background: The diagnosis of pemphigus vulgaris (PV) and pemphigus
foliaceous (PF) rests upon clinical, histological and
immunofluorescence features. Enzyme-linked immunosorbent assay (ELISA)
test ...and immunoblot (IB) assay have shown variable sensitivity and
specificity. Aims: We compared the utility of ELISA and IB in
pemphigus patients. Methods: Sixty-six pemphigus cases (PV-54, PF-12)
and 72 controls (other vesicobullous disorders and healthy controls)
were inducted. ELISA for anti-Dsg 3 and 1 antibodies and IB assay were
performed. Results: On ELISA, both mean anti-Dsg 1 and 3 titers were
raised in PV and PF. Mean anti-Dsg 1 in mucocutaneous PV was
significantly higher than in mucosal PV and mean anti-Dsg 3 was
significantly raised in PV than in PF. Anti-Dsg 1 and 3 in the control
group were negative. Sensitivity and specificity of ELISA in PV was
98.14% and 90.5% while in PF it was 91.6% and 61.1%, respectively.On IB
in PV, 36 cases (66.67%) showed the 130 kDa and 160 kDa antigen bands,
12 (22.2%) only the 130 kDa and six (11.1%) only the 160 kDa band.
Eight of the nine pure mucosal cases (88.8%) showed only the 130 kDa.
In PF, only the 160 kDa antigen was detected. These antigens were not
identified in the control group. Sensitivity and specificity of IB in
PV was 88.9% and 100% and in PF it was 100% and 95.2%, respectively.
Conclusion: Both tests could differentiate pemphigus from other
dermatoses, including other blistering disorders. ELISA could not make
a distinction between PV and PF or between the various clinical
phenotypes of PV. IB differentiated between PV and PF and the different
clinical variants of PV.
Antimitochondrial antibodies (AMAs) are the classic serologic marker in primary biliary cirrhosis (PBC). However, there have been only limited attempts to study changes in titer or isotype analysis ...of such AMAs in patients followed for long periods of time. We took advantage of stored sera from well-characterized patients with PBC followed for a period of 7-28 years (mean duration of 13.5 years). Immunoblot and enzyme-linked immunosorbant assays were performed against PDC-E2, BCOADC-E2 and OGDC-E2 as well as isotype analysis of antigen-specific IgG, IgA and IgM antibodies against each of these mitochondrial autoantigens. Sera were analyzed for total IgG, IgA and IgM by radial immunodiffusion. The sera titer of AMAs was significantly higher in younger patients with PBC. Indeed, age of onset of clinical PBC was a significant predictor for the highest values of sera AMAs. In contrast, the AMA titer did not significantly change over time in this prolonged longitudinal study. The total sera levels of the individual immunoglobulins did not show a time-dependent change, when based on age of onset of the disease. Higher titers of AMAs were noted in the younger patients. Furthermore, despite this long follow-up, there was no evidence for a significant change in AMA levels; also, levels were not influenced by drug therapy used during the period of observation.
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