Protein macroarray profiling of serum autoantibodies in pseudoexfoliation glaucoma.
OBJECTIVE
Complex repertoires of IgG autoantibodies have been detected against ocular antigens in patients with glaucoma. The goal was to identify and characterize the IgG autoantibody repertoires in sera of patients with pseudoexfoliation glaucoma (PXFG) with protein macroarrays.


METHODS
Serum samples of 21 patients with PXFG and 19 age- and sex-matched control subjects were profiled on high-density colony protein macroarrays expressing His-tagged recombinant human proteins derived from a human fetal brain cDNA library. Statistically prevalent expression clones in the PXFG group were sequenced. mRNA expression of identified antigens was examined in the rat ganglion cell line RGC-5 and in human brain and optic nerve cDNA. The IgG immunoreactivity of the sera of 20 control and 26 PXFG patients to purified C6orf129 was analyzed in a reverse enzyme-linked immunosorbent assay.


RESULTS
An increased prevalence was detected among the PXFG patients of serum antibodies to seven proteins: C6orf129; stathmin-like 4; transmembrane protein 9 domain family, member B; fibroblast growth factor receptor 3; cleft lip and palate transmembrane protein 1; EH-domain-containing protein 1; and eukaryotic translation elongation factor 2. All antigens were expressed in the RGC-5 cells and in cDNA from human brain and optic nerve, with the exception of stathmin-like 4, which was not expressed in the RGC-5 cells. The patients with PXFG had increased anti-C6orf129 IgG immunoreactivity compared with that in the control subjects (P < 0.05).


CONCLUSIONS
Screening high-density protein arrays identifies unique antibody profiles that may discriminate between patients with and without PXFG. Characterization of the autoantibody repertoire may provide new insights into the pathophysiology of PXFG.
Dervan
Edward W
EW
Institute of Ophthalmology, Mater Misericordiae University Hospital, Dublin, Ireland. edervan@mac.com
Chen
Hong
H
Ho
Su Ling
SL
Brummel
Nikola
N
Schmid
Jasmin
J
Toomey
David
D
Haralambova
Margarita
M
Gould
Edith
E
Wallace
Deborah M
DM
Prehn
Jochen H M
JH
O'Brien
Colm J
CJ
Murphy
Derek
D
D000368:Aged; D000818:Animals; D001323:Autoantibodies / Q000097:blood*; D001324:Autoantigens / Q000235:genetics / Q000276:immunology*; D001921:Brain / Q000276:immunology; D002460:Cell Line; D002896:Chromosomes, Human, Pair 6 / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D017889:Exfoliation Syndrome / Q000276:immunology*; D005260:Female; D005902:Glaucoma, Open-Angle / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D008969:Molecular Sequence Data; D016366:Open Reading Frames / Q000235:genetics; D009900:Optic Nerve / Q000276:immunology; D040081:Protein Array Analysis; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D012165:Retinal Ganglion Cells / Q000276:immunology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA
D001323:Autoantibodies; D001324:Autoantigens; D007074:Immunoglobulin G; D012333:RNA, Messenger