Inhibition of transglutaminase 2 enzymatic activity ameliorates the anti-angiogenic effects of coeliac disease autoantibodies.
OBJECTIVE
Earlier work has demonstrated that serum autoantibodies from coeliac patients targeted against transglutaminase 2 (TG2) inhibit in vitro angiogenesis. The aim of this study was to establish whether coeliac patient-derived monoclonal TG2-targeted antibodies produced by recombination technology exert similar anti-angiogenic effects to serum-derived coeliac autoantibodies. In addition, we studied whether the monoclonal patient autoantibodies modulate endothelial cell TG2 activity and whether such modulation is related to the anti-angiogenic effects.


METHODS
The influence of coeliac patient-derived monoclonal TG2-targeted antibodies on endothelial cell tubule formation was studied using a three-dimensional angiogenic cell culture model. Endothelial cell TG2 enzymatic activity was determined by means of a live-cell enzyme-linked immunosorbent assay.


RESULTS
Coeliac patient-derived monoclonal TG2-targeted antibodies produced by recombination technology inhibited endothelial tubule formation and enhanced the crosslinking activity of TG2. When this enzymatic activity was inhibited using site-directed irreversible TG2 inhibitors in the presence of autoantibodies, in vitro angiogenesis reverted to the control level.


CONCLUSIONS
Since we found a significant negative correlation between endothelial cell angiogenesis and TG2 activity, we suggest that the anti-angiogenic effects of coeliac patient-derived TG2-targeted autoantibodies are exerted by enhanced enzymatic activity of TG2.
Caja
Sergio
S
Paediatric Research Centre, Medical School, University of Tampere, Tampere, Finland.
Myrsky
Essi
E
Korponay-Szabo
Ilma R
IR
Nadalutti
Cristina
C
Sulic
Ana-Marija
AM
Lavric
Miha
M
Sblattero
Daniele
D
Marzari
Roberto
R
Collighan
Russell
R
Mongeot
Alexandre
A
Griffin
Martin
M
Mäki
Markku
M
Kaukinen
Katri
K
Lindfors
Katri
K
D000704:Analysis of Variance; D000911:Antibodies, Monoclonal / Q000276:immunology*; D001323:Autoantibodies / Q000502:physiology*; D001706:Biopsy; D015153:Blotting, Western; D002446:Celiac Disease / Q000201:enzymology* / Q000276:immunology*; D018929:Cell Culture Techniques; D042783:Endothelial Cells / Q000276:immunology; D004730:Endothelium, Vascular / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D019204:GTP-Binding Proteins / Q000037:antagonists & inhibitors* / Q000276:immunology*; D006801:Humans; D007070:Immunoglobulin A / Q000276:immunology; D009389:Neovascularization, Pathologic / Q000276:immunology*; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D011503:Transglutaminases / Q000037:antagonists & inhibitors* / Q000276:immunology*
D000911:Antibodies, Monoclonal; D001323:Autoantibodies; D007070:Immunoglobulin A; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D011503:Transglutaminases; D019204:GTP-Binding Proteins