PT  - JOURNAL ARTICLE
AU  - Carolina Llanos
AU  - Edward K.L. Chan
AU  - Songqing Li
AU  - Grant X. Abadal
AU  - Peter Izmirly
AU  - Caroline Byrne
AU  - Robert M. Clancy
AU  - Jill P. Buyon
TI  - Antibody Reactivity to α-Enolase in Mothers of Children with Congenital Heart Block
AID  - 10.3899/jrheum.080860
DP  - 2009 Feb 01
TA  - The Journal of Rheumatology
PG  - jrheum.080860
4099  - http://www.jrheum.org/content/early/2009/02/04/jrheum.080860.short
4100  - http://www.jrheum.org/content/early/2009/02/04/jrheum.080860.full
AB  - Objective To evaluate the frequency of anti-α-enolase antibodies in the sera of mothers whose children have congenital heart block (CHB), given provocative results in which α-enolase, a membrane protein, was recognized by monoclonal antibodies reactive with the peptide p200 of 52 kDa Ro/SSA in a neonatal rat heart library. Methods An ELISA using a recombinant α-enolase protein was developed. Sera from 100 anti-Ro52+ CHB mothers in the Research Registry for Neonatal Lupus, 50 patients with systemic lupus erythematosus (SLE; 7 anti-Ro52+), and 48 healthy controls were tested for anti-α-enolase reactivity. Results There were no significant differences in the median values obtained from CHB mothers, patients with SLE, or controls at each of the dilutions tested. Only 7 (7%) at 1:100 dilution and 2 (2%) at 1:1000 dilution of 100 CHB sera were 3 standard deviations above the mean value obtained for controls. Preincubation with recombinant Ro52 did not inhibit anti-α-enolase reactivity. Conclusion The low frequency of anti-α-enolase antibodies in the sera of CHB mothers and the absence of apparent cross-reactivity with Ro52 suggest that antibodies to Ro52 are not likely to mediate CHB via binding to α-enolase.