Open AccessAnti‐p57: a novel association with neonatal lupus
Author(s) -
MADDISON P. J.,
LEE L.,
REICHLIN M.,
SINCLAIR A.,
WASSON C.,
SCHEMMER G.,
REICHLIN M.
Publication year - 1995
Publication title -
clinical & experimental immunology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.329
H-Index - 135
eISSN - 1365-2249
pISSN - 0009-9104
DOI - 10.1111/j.1365-2249.1995.tb03470.x
Subject(s) - antibody , immunology , antigen , cord blood , systemic lupus erythematosus , biology , medicine , microbiology and biotechnology , disease
SUMMARY IgG antibodies to a 57‐kD protein (p57) present in various human and bovine extracts were detected by immunoblotting in the serum of the mother of a baby with congenital heart block, but not in the corresponding cord blood, suggesting specific antibody consumption in the baby. Since this indicates a possible functional role for these antibodies, the antigen target was characterized and the association of the antibodies to heart block was further studied. A human K562 λgt11 cDNA library was screened and two clones were identified whose products reacted with the prototype serum. Antibody affinity‐purified by use of the cloned gene products reacted on immunoblot with the 57‐kD band. Partial sequences of both inserts were identical, but differed from DNA encoding the Ro(SSA) and La(SSB) antigens. Antibodies to the p57 were detected in 10% of systemic lupus erythematosus (SLE) sera, almost exclusively in association with anti‐Ro(SSA). Furthermore, they were present in 38% (8/21) mothers of babies with neonatal lupus expressing either cardiac or cutaneous manifestations. Antibodies to this 57‐kD protein may be an additional risk factor for neonatal lupus in anti‐Ro‐positive women. Moreover, disappearance of antibody from cord blood suggests that they may have a role in disease manifestations.