FIG. 1.

Increase in antibody levels during treatment. Only samples with an antibody titer (ID₅₀) below the cutoff, defined as greater than the mean plus two SD of values from control sera, are shown. Gridlines indicate multiples of the cutoff titer for each monoclonal antibody probe. Antibody levels are defined by extrapolation as the dilution that reduces the maximal binding of the monoclonal antibody by 50%. The second value indicates the first positive titer obtained during treatment for tuberculosis.