FIG. 4.

Antigen specificity and recognition of an immunodominant epitope for GPLs. GPL core concentrations ranging from 1 to 5 μg/ml were added to the EIA with a mixture of GPLs prepared from 11 reference strains of MAC and GPL core of a serotype 4 strain. Sera were from five patients with MAC pulmonary disease, patient A (○), patient B (•), patient C (□), patient D (▪), and patient E (▵). Addition of GPL core antigen inhibited the level of optical density (OD) by IgG (panels A and D), IgA (panels B and E), and IgM (panels C and F) antibodies against GPLs (panels A, B, and C) and GPL core (panels D, E, and F) in a dose-dependent fashion.