Calcium activation of tissue transglutaminase in radioligand binding and enzyme-linked autoantibody immunoassays in childhood celiac disease.
Agardh, Daniel LU ; Roth, Bodil LU ; Lernmark, Åke LU
and Stenberg, Pål
(2005)
In Clinica Chimica Acta
358(1-2).
p.95-103
- Abstract
- Background
Conflicting data have been published concerning the effect of calcium on binding of autoantibodies to tissue transglutaminase (tTG) in celiac disease (CD).
Methods
IgA-tTG and IgG-tTG were measured with radioligand binding assays (RBA) using human recombinant (hr) 35S-tTG produced in lysate of rabbit reticulocytes and with guinea pig (gp) tTG ELISA in 51 CD children (median: 5.7 years) and 35 controls (median: 2.2 years). Assays were performed with and without calcium.
Results
In hr-tTG RBA, IgA-tTG levels remained unchanged after calcium detecting 50/51 CD children and 1/35 controls (p < 0.0001). IgG-tTG levels decreased with calcium (p < 0.0001)... (More) - Background
Conflicting data have been published concerning the effect of calcium on binding of autoantibodies to tissue transglutaminase (tTG) in celiac disease (CD).
Methods
IgA-tTG and IgG-tTG were measured with radioligand binding assays (RBA) using human recombinant (hr) 35S-tTG produced in lysate of rabbit reticulocytes and with guinea pig (gp) tTG ELISA in 51 CD children (median: 5.7 years) and 35 controls (median: 2.2 years). Assays were performed with and without calcium.
Results
In hr-tTG RBA, IgA-tTG levels remained unchanged after calcium detecting 50/51 CD children and 1/35 controls (p < 0.0001). IgG-tTG levels decreased with calcium (p < 0.0001) in CD children and detected 48/51 with and 49/51 without calcium as compared to 1/35 controls (p < 0.0001). In gp-tTG ELISA, levels increased with calcium (p < 0.0001) making it possible to detect an additional three to a total of 50/51 with IgA-tTG and 13 to 39/51 CD children with IgG-tTG compared to 4/35 and 8/35 controls (respectively, p < 0.0001). Rabbit reticulocytes displayed calcium-dependent tTG activity.
Conclusions
Calcium increased binding of IgA-tTG and IgG-tTG in the ELISA test. The reverse effect observed in RBA may be explained by competitive binding between calcium activated native rabbit reticulocyte tTG and hr 35S-tTG. tTG autoantibody assays may need taking calcium into account for accurate diagnostic sensitivity and specificity for CD. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/140151
- author
- Agardh, Daniel
LU
; Roth, Bodil
LU
; Lernmark, Åke
LU
and Stenberg, Pål
- organization
- publishing date
- 2005
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Calcium, Celiac disease, Radioimmunoassays, Tissue transglutaminase
- in
- Clinica Chimica Acta
- volume
- 358
- issue
- 1-2
- pages
- 95 - 103
- publisher
- Elsevier
- external identifiers
-
- wos:000231001600010
- pmid:15946660
- scopus:22144488118
- pmid:15946660
- ISSN
- 0009-8981
- DOI
- 10.1016/j.cccn.2005.02.027
- language
- English
- LU publication?
- yes
- id
- 87bff488-385d-405f-a6aa-39899590e853 (old id 140151)
- date added to LUP
- 2016-04-01 11:43:17
- date last changed
- 2022-01-26 17:12:10
@article{87bff488-385d-405f-a6aa-39899590e853,
abstract = {{Background<br/><br>
<br/><br>
Conflicting data have been published concerning the effect of calcium on binding of autoantibodies to tissue transglutaminase (tTG) in celiac disease (CD).<br/><br>
Methods<br/><br>
<br/><br>
IgA-tTG and IgG-tTG were measured with radioligand binding assays (RBA) using human recombinant (hr) 35S-tTG produced in lysate of rabbit reticulocytes and with guinea pig (gp) tTG ELISA in 51 CD children (median: 5.7 years) and 35 controls (median: 2.2 years). Assays were performed with and without calcium.<br/><br>
Results<br/><br>
<br/><br>
In hr-tTG RBA, IgA-tTG levels remained unchanged after calcium detecting 50/51 CD children and 1/35 controls (p < 0.0001). IgG-tTG levels decreased with calcium (p < 0.0001) in CD children and detected 48/51 with and 49/51 without calcium as compared to 1/35 controls (p < 0.0001). In gp-tTG ELISA, levels increased with calcium (p < 0.0001) making it possible to detect an additional three to a total of 50/51 with IgA-tTG and 13 to 39/51 CD children with IgG-tTG compared to 4/35 and 8/35 controls (respectively, p < 0.0001). Rabbit reticulocytes displayed calcium-dependent tTG activity.<br/><br>
Conclusions<br/><br>
<br/><br>
Calcium increased binding of IgA-tTG and IgG-tTG in the ELISA test. The reverse effect observed in RBA may be explained by competitive binding between calcium activated native rabbit reticulocyte tTG and hr 35S-tTG. tTG autoantibody assays may need taking calcium into account for accurate diagnostic sensitivity and specificity for CD.}},
author = {{Agardh, Daniel and Roth, Bodil and Lernmark, Åke and Stenberg, Pål}},
issn = {{0009-8981}},
keywords = {{Calcium; Celiac disease; Radioimmunoassays; Tissue transglutaminase}},
language = {{eng}},
number = {{1-2}},
pages = {{95--103}},
publisher = {{Elsevier}},
series = {{Clinica Chimica Acta}},
title = {{Calcium activation of tissue transglutaminase in radioligand binding and enzyme-linked autoantibody immunoassays in childhood celiac disease.}},
url = {{https://lup.lub.lu.se/search/files/2610991/624760.pdf}},
doi = {{10.1016/j.cccn.2005.02.027}},
volume = {{358}},
year = {{2005}},
}