Clinical and diagnostic laboratory immunology
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Clin. Diagn. Lab. Immunol. · Jul 2004
Evaluation of recombinant antigen-based assays for diagnosis of bullous autoimmune diseases.
The diagnosis of autoimmune bullous diseases is based on clinical observation and on the presence of autoantibodies directed to molecules involved in the adhesion systems of the skin. Immunofluorescence assays are the currently accepted method for detection of autoantibodies; such assays depend greatly on the skill of operators and are difficult to standardize. Recombinant desmoglein-1 (Dsg1), Dsg3, and BP180 peptides, the main autoantigens in pemphigus or bullous pemphigoid, have been used to develop new quantitative enzyme immunoassays (EIA) for the detection of specific antibodies. ⋯ The BP180-based assay was positive for 66.6% of patients with bullous pemphigoid and for none of the patients with mucous membrane pemphigoid, and no reactivity was detected in the control sera. In conclusion, the anti-Dsg1 and anti-Dsg3 assays are useful in the diagnosis of pemphigus and provide information on the clinical phenotype of the disease. However, the sensitivity of EIA for detection of autoantibodies in bullous pemphigoid should be improved by the use of additional antigens or epitopes.
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Clin. Diagn. Lab. Immunol. · Mar 2004
Profiles of antibody responses against severe acute respiratory syndrome coronavirus recombinant proteins and their potential use as diagnostic markers.
A new coronavirus (severe acute respiratory syndrome coronavirus [SARS-CoV]) has been identified to be the etiological agent of severe acute respiratory syndrome. Given the highly contagious and acute nature of the disease, there is an urgent need for the development of diagnostic assays that can detect SARS-CoV infection. For determination of which of the viral proteins encoded by the SARS-CoV genome may be exploited as diagnostic antigens for serological assays, the viral proteins were expressed individually in mammalian and/or bacterial cells and tested for reactivity with sera from SARS-CoV-infected patients by Western blot analysis. ⋯ Alternatively, this could be due to the difference in the sensitivities of the two methods. The immunoreactivities to these recombinant viral proteins are highly specific, as sera from 100 healthy donors did not react with any of them. These results suggest that recombinant N, S, and U274 proteins may be used as antigens for the development of serological assays for SARS-CoV.
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Clin. Diagn. Lab. Immunol. · Jan 2004
Cytokine production and monocyte HLA-DR expression as predictors of outcome for patients with community-acquired severe infections.
This study was performed to evaluate the impact of pro- and anti-inflammatory molecules and human leukocyte antigen DR (HLA-DR) expression as markers of immune status for the final outcome of septic patients. The study included 30 patients with severe sepsis due to community-acquired infections. Concentrations of tumor necrosis factor alpha (TNF-alpha), interleukin-6 (IL-6), IL-8, IL-10, and transforming growth factor beta1 (TGF-beta1) in serum, as well as monocyte HLA-DR expression, were determined on admission and on days 3, 10, 13, and 17 during hospitalization. ⋯ Independent risk factors of mortality were IL-10 levels on days 3 and 10, while monocyte HLA-DR expression on admission was a good predictor for survival. Several pro- and anti-inflammatory cytokines are oversynthesized during severe infections, especially in patients with a poor outcome. Monocyte HLA-DR expression is an early and constant predictive marker for survival in severe sepsis, while serum IL-10 levels on days 3 and 10 have negative prognostic value for the final outcome.
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Clin. Diagn. Lab. Immunol. · Nov 2002
Tumor necrosis factor gene polymorphisms, leukocyte function, and sepsis susceptibility in blunt trauma patients.
The tumor necrosis factor alpha (TNF-alpha) -308 G/A and TNF-beta NcO1 polymorphisms have been described to be associated with an increased risk for sepsis in critically ill patients. Functional consequences associated with these polymorphisms remain unclear. We compared the genotype distribution of these TNF polymorphisms with susceptibility to severe sepsis and leukocyte function in blunt trauma patients (n = 70; mean injury severity score, 24 points [range, 4 to 57). ⋯ Patients homozygous for the TNFB1 or TNFB2 allele showed a persistently higher cytokine-producing capacity during at least 4 to 8 days after trauma than the heterozygotes. In patients homozygous for the TNF1 allele, a higher TNF-alpha- and IL-8-producing capacity was found only at day 1 after trauma. Although the TNF-beta NcO1 polymorphism appears to be less likely to be causative for development of severe sepsis after trauma, it is thus far the only genetic marker identified which can be used as a relevant risk estimate for severe sepsis in trauma patients immediately after the injury.
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Clin. Diagn. Lab. Immunol. · Jul 2000
Lack of utility of specific immunoglobulin G antibody avidity for serodiagnosis of reactivated toxoplasmosis in immunocompromised patients.
The avidities of Toxoplasma-specific immunoglobulin G serum antibodies were measured in immunocompromised patients presenting with cerebral or extracerebral toxoplasmosis and/or serological reactivation. Since avidity remained high and stable in 39 of 40 patients with toxoplasmosis and 27 of 28 patients with serological reactivation, we conclude that this test cannot help diagnose toxoplasmosis in these patients.