Figure 2.

Kinetics of 60-min serum clearance of anti-dansyl IgA1, IgA2m(1), IgA2m(2), and IgA2(n) in C57BL/6 mice. 1 μg of each of the ¹²⁵I-labeled proteins was injected into the tail vein. At indicated times after injection, aliquots of blood obtained from the retroorbital venous plexus were precipitated with 10% TCA to determine protein-bound radioactivity. The first three data points were used to extrapolate the 100% value at zero time point using linear regression analysis. Each data point represents the mean ± SD of three mice. Data are representative of multiple experiments performed using different preparations of IgA containing varying ratios of polymer to monomer. The superimposed dotted gridlines highlight the time (t _50%) required for the disappearance of 50% of the administered dose.