Identification of target antigens of antiendothelial cell antibodies in healthy individuals: A proteomic approach.
In order to identify target antigens of anti-endothelial cell (anti-EC) antibodies (AECA) in healthy individuals, we have used a proteomic approach combining 2-DE and immunoblotting. Whole cell protein extracts obtained from human umbilical vein EC (HUVEC) cultures were used as a source of antigens. Serum IgG from 12 healthy blood donors were tested at a concentration of 200 microg/mL. Targeted spots were identified by MS. The HUVEC proteome was composed of 884 protein spots. Among these, 61 +/- 25.8 (mean +/- SD) spots were recognized by serum IgG from healthy individuals, with marked differences from one individual to another. Among these spots, 11 were recognized by serum IgG from all healthy individuals tested. These spots corresponded to six different proteins with several spots corresponding to different isoforms of the same protein. Target antigens were: cytoskeletal proteins (beta-actin, alpha-tubulin, and vimentin); glycolytic enzymes (glucose-3-phosphate-deshydrogenase and alpha-enolase); and prolyl-4-hydroxylase beta subunit, a member of the disulfide isomerase family. This study shows that the repertoire of IgG AECA is heterogeneous among healthy individuals. IgG from all of the healthy individuals tested recognized a restricted set of highly conserved ubiquitous proteins playing key roles in cell biology and maintenance of homeostasis.
Servettaz
Amélie
A
Faculté de Médecine, UPRES-EA 4058, Université Paris Descartes, Paris, France.
Guilpain
Philippe
P
Camoin
Luc
L
Mayeux
Patrick
P
Broussard
Cédric
C
Tamby
Mathieu C
MC
Tamas
Nicolas
N
Kaveri
Srini V
SV
Guillevin
Loïc
L
Mouthon
Luc
L
D000328:Adult; D000368:Aged; D001323:Autoantibodies / Q000378:metabolism*; D001324:Autoantigens / Q000032:analysis*; D003598:Cytoskeletal Proteins / Q000276:immunology; D015180:Electrophoresis, Gel, Two-Dimensional; D042783:Endothelial Cells / Q000737:chemistry / Q000276:immunology*; D005260:Female; D006801:Humans; D015151:Immunoblotting; D008297:Male; D013058:Mass Spectrometry; D008875:Middle Aged; D040901:Proteomics / Q000379:methods*; D014471:Umbilical Veins / Q000166:cytology
D001323:Autoantibodies; D001324:Autoantigens; D003598:Cytoskeletal Proteins; C087589:anti-endothelial cell antibody