FIG. 2.
The concentration of antibodies directed against UspA1360-680 containing the fibronectin-binding (UspA1299-452) and CEACAM-binding (UspA1557-704) domains increased with age. Human sera were diluted in 1:100. The horizontal bars represent the median values. Data shown are the averages of two separate ELISAs performed independently. (A) Low levels of antibodies directed against UspA1 were found in children aged 6 months to 1 year. (B) Elevated levels of antibodies found with increasing age were directed mainly against relatively conserved domains in UspA1360-680. (C) High levels of antibodies directed against UspA1360-680 were found in adults. (D) Recombinant truncated UspA1 fragments spanning the entire protein were used as bait in ELISAs. Abbreviations: abs, antibodies; OD450, optical density at 450 nm.