scholarly journals Purification and Characterisation of Badger IgA and Its Detection in the Context of Tuberculosis

2019 ◽  
Vol 6 (4) ◽  
pp. 89
Author(s):  
Deanna Dalley ◽  
Sandrine Lesellier ◽  
Francisco J. Salguero ◽  
Mark A. Chambers
Keyword(s):  
Tracheal Aspirate ◽  
Secretory Component ◽  
Secretory Iga ◽  
Respiratory Pathogens ◽  
Serological Tests ◽  
Mucosal Vaccination ◽  
Immunodominant Antigen ◽  
Iga Response ◽  
European Badgers ◽  
Dose Dependent

European badgers are a wildlife reservoir of bovine tuberculosis in parts of Great Britain. Accurate diagnosis of tuberculosis in badgers is important for the development of strategies for the control of the disease. Sensitive serological tests for badger TB are needed for reasons such as cost and simplicity. Assay of mucosal IgA could be useful for diagnosing respiratory pathogens such as Mycobacterium bovis and for monitoring the response to mucosal vaccination. To develop an IgA assay, we purified secretory IgA from badger bile, identifying secretory component (SC), heavy chain (HC) and light chain (LC), at 66, 46 and 27 Kda, respectively, on the basis of size comparison with other species. Monoclonal antibodies (mAbs) were generated to purified IgA. We selected two for ELISA development. The detection limit of the IgA-specific mAbs was found to be approximately 20 ng/mL when titrated against purified badger bile. One monoclonal antibody specific for badger IgA was used to detect IgA in serum and tracheal aspirate with specificity to an immunodominant antigen of M. bovis. An M. bovis infection dose-dependent IgA response was observed in experimentally infected badgers. IgA was also detected by immunohistochemistry in the lungs of bTB-infected badgers. With further characterisation, these represent new reagents for the study of the IgA response in badgers.

Secretory Immunoglobulin a in Oral and Respiratory Passages in Man

1975 ◽  
Vol 84 (20_suppl) ◽  
pp. 1-23 ◽  
Author(s):  
Goro Mogi
Keyword(s):  
Immunoglobulin A ◽  
Secretory Component ◽  
Secretory Iga ◽  
Secretory Cells ◽  
Antigenic Relationship ◽  
Serum Iga ◽  
Human Colostrum ◽  
Specific Antisera ◽  
Antigenic Relationships ◽  
Secretory Immunoglobulin

Secretory IgA (SIgA) is the predominant immunoglobulin in certain external secretions and may have an important role in immunological mucosal resistance. SIgA differs in chemical and immunological properties from serum IgA. The present study was undertaken to investigate the antigenic relationship between SIgA, free secretory component (FSC) and serum IgA and the localization of SIgA as well as other immunological classes in tissues of oral and respiratory passages by use of immunofluorescence technique. SIgA and FSC were highly purified from human colostrum and rabbit anti-SIgA and anti-SC antisera were prepared. On the basis of antigenic relationships between SIgA, FSC and serum IgA, it was emphasized that individual specific antisera for SC and IgA and/or SIgA should be used in immunochemical or immunohistological investigations for SIgA. The present study failed to detect SC determinants in palatine and lingual tonsils. However, it was evident that cells present in the pharyngeal tonsillar epithelium contain SC determinants. SC molecules may be synthesized in certain secretory cells of mucous membrane and glandular epithelium and the combining of SC with IgA could occur in the cytoplasm of epithelial cells, the intercellular spaces and/or in the lumens of glandular acini and ductules.

Rat bile as a convenient source of secretory IgA and free secretory component

1977 ◽  
Vol 7 (8) ◽  
pp. 588-590 ◽  
Author(s):  
Isabel Lemaître-Coelho ◽  
G. D. F. Jackson ◽  
J. -P. Vaerman
Keyword(s):  
Secretory Component ◽  
Secretory Iga ◽  
Rat Bile

scholarly journals Head-to-Head Comparison of Two SARS-CoV-2 Serology Assays

2020 ◽  
Vol 5 (6) ◽  
pp. 1351-1357 ◽  
Author(s):  
Anna E Merrill ◽  
J Brooks Jackson ◽  
Alexandra Ehlers ◽  
Dena Voss ◽  
Matthew D Krasowski
Keyword(s):  
Time Frame ◽  
Cross Reactivity ◽  
Molecular Techniques ◽  
Respiratory Pathogens ◽  
Serological Tests ◽  
Antibody Assays ◽  
Clinically Significant ◽  
Low Prevalence ◽  
Roche Diagnostics ◽  
Unique Potential

Abstract Background While molecular techniques remain the gold standard for diagnosis of acute SARS-CoV-2 infection, serological tests have the unique potential to ascertain how much of the population has been exposed to the COVID-19 pathogen. There have been limited published studies to date documenting the performance of SARS-CoV-2 antibody assays. Methods We compared the DiaSorin Liaison SARS-CoV-2 S1/S2 IgG and Roche Diagnostics Elecsys Anti-SARS-CoV-2 assays using 228 samples spanning patients with positive PCR for SARS-CoV-2, patients with compatible symptoms but negative PCR, pre-COVID specimens, and potential cross-reactives. Results Both assays detected antibodies in 18/19 samples collected at least one week after a positive PCR result. Neither method consistently detected antibodies in specimens collected within one week of a positive PCR result (sensitivity < 50%), but antibodies were detected by only Roche in four samples in this time frame. Using 139 pre-COVID and 35 PCR-negative samples, the Roche and DiaSorin assays demonstrated specificities of 100.0% and 98.9%, respectively. Neither assay demonstrated cross-reactivity from other coronaviruses (229E, HKU1, NL63, OC43), respiratory pathogens (adenovirus, metapneumovirus, rhinovirus/enterovirus), or antibodies to other viruses (HIV, EBV, CMV, HBV, HCV, HAV). Discussion Overall, the qualitative interpretations afforded by the Roche and DiaSorin assays agreed for 97% of samples evaluated. Minor discrepancies in sensitivity and specificity were observed between methods, with the differences in specificity more clinically significant for our low-prevalence population. For the DiaSorin assay, all disagreements with the Roche assay occurred in samples with quantitative signals near the cut-off determining positivity.

scholarly journals An outbreak of infection due to verocytotoxin-producing Escherichia coli O157 in four families: the influence of laboratory methods on the outcome of the investigation

1997 ◽  
Vol 119 (2) ◽  
pp. 113-119 ◽  
Author(s):  
P. A. CHAPMAN ◽  
C. A. SIDDONS ◽  
J. MANNING ◽  
C. CHEETHAM
Keyword(s):  
Immunomagnetic Separation ◽  
Bloody Diarrhoea ◽  
Farm Animals ◽  
Secretory Iga ◽  
Macconkey Agar ◽  
E Coli ◽  
Faecal Samples ◽  
The Family ◽  
Iga Response

Three members of family A, who had diarrhoea on 20 October, lived on a small arable farm which had 10 cattle. Manure from the animals was used to fertilize the ground for growing potatoes which were then offered for retail sale, unwashed, directly from the farm. The mother from family B bought potatoes, which were covered with manure, from family A in early November and over the subsequent 10 days she became ill with diarrhoea and her daughter and son both became ill with bloody diarrhoea. The mother from family C visited family B while the daughter from the latter family was symptomatic; the mother developed diarrhoea several days later. The mother and two sons from family D visited family B while the son from the latter family was symptomatic; the first son developed bloody diarrhoea 6 days later which progressed to development of haemolytic-uraemic syndrome. Direct culture of faecal samples onto cefixime rhamnose sorbitol MacConkey agar failed to isolate E. coli O157 from any of the symptomatic patients, and direct culture onto cefixime tellurite sorbitol MacConkey agar isolated the organism from only one patient. In contrast, a combination of isolation of E. coli O157 by immunomagnetic separation and detection of E. coli O157-specific secretory IgA, suggested E. coli O157 infection in all eight symptomatic patients, but not in any of the family members who were not ill. Two children who excreted the organism for 60 and 89 days respectively were the only two patients who did not develop a secretory IgA response. E. coli O157 was not isolated from potatoes from the farm and faecal samples from the farm animals were not available for examination. The study illustrates the need to use the most sensitive methods available during the investigation and follow up of cases of E. coli O157 infection.

Secretory IgA response in oral immunotherapy.

Allergy ◽  
1994 ◽  
Vol 49 (9) ◽  
pp. 760-765 ◽  
Author(s):  
E. Taudorf ◽  
C. Møller ◽  
M. W. Russell
Keyword(s):  
Oral Immunotherapy ◽  
Secretory Iga ◽  
Iga Response

Human eosinophils express a receptor for secretory component. Role in secretory IgA-dependent activation

1995 ◽  
Vol 25 (1) ◽  
pp. 117-125 ◽  
Author(s):  
Bouchaib Lamkhioued ◽  
Abdelillah Soussi Gounni ◽  
Valérie Gruart ◽  
Annick Pierce ◽  
André Capron ◽  
...  
Keyword(s):  
Secretory Component ◽  
Secretory Iga

scholarly journals REGULATION OF THE IMMUNE RESPONSE: SUPPRESSIVE AND ENHANCING EFFECTS OF PASSIVELY ADMINISTERED ANTIBODY

1971 ◽  
Vol 133 (5) ◽  
pp. 987-1003 ◽  
Author(s):  
Carolyn S. Pincus ◽  
Michael E. Lamm ◽  
Victor Nussenzweig
Keyword(s):  
Immune Response ◽  
Antibody Formation ◽  
Secretory Component ◽  
Secretory Iga ◽  
Antigenic Determinants ◽  
Antibody Synthesis ◽  
Serum Iga ◽  
Iga Antibody ◽  
Antigen Antibody

The ability of passively administered antibody to suppress the immune response against homologous antigenic determinants while concomitantly enhancing the response against other unrelated determinants of the same antigen molecule has been established in two distinct antigen-antibody systems: (a) guinea pig γ2-immunoglobulin + passive anti-F(ab')2 antibody, where suppression of anti-F(ab')2 antibody synthesis is accompanied by enhancement of the anti-Fc response; and (b) human secretory IgA + passive anti-serum IgA antibody, where suppression of antibody production against the α and L chains accompanies augmentation of the response to the secretory component. The mechanisms of the suppressive and enhancing effects are probably unrelated for the following reasons: (a) Enhancement of the response to certain determinants may be obtained without discernible suppression of the response to the homologous determinants; and (b) the F(ab')2 fragments of passive antibody can mediate immune suppression but were not observed to enhance the response against the unrelated determinants of the same antigen molecule. Also, the timing for achieving maximum suppression or enhancement of antibody formation is not the same; enhancement was obtained only at a later time. Both the enhancement and suppressive effects were obtained with the purified γG fraction of antisera. This finding rules out an exclusive role of γM antibody in the enhancement phenomenon.

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