Screening of a HUVEC cDNA library with transplant-associated coronary artery disease sera identifies RPL7 as a candidate autoantigen associated with this disease

A HUVEC cDNA library was screened with sera from two patients who had developed transplant-associated coronary artery disease (TxCAD) following cardiac transplantation. A total of six positive clones were isolated from a primary screen of 40 000 genes. Subsequent DNA sequence analysis identified these to be lysyl tRNA synthetase, ribosomal protein L7, ribosomal protein L9, beta transducin and TANK. Another gene whose product could not be identified showed homology to a human cDNA clone (DKFZp566M063) derived from fetal kidney. Full-length constructs of selected genes were expressed as his-tag recombinant fusion proteins and used to screen a wider patient base by ELISA to determine prevalence and association with TxCAD. Of these ribosomal protein L7 showed the highest prevalence (55.6%) with TxCAD sera compared to 10% non-CAD.