Western blot analysis of undepleted sera from rats treated with PBS alone (1), pIC alone (2), pIC + H-1 (3) or pIC + KRV (4). Protein concentration was assessed by the Bradford assay and equal protein was loaded in each well. Rats were tail bled (a) or cardiac bled (b) at indicated time points. Purified rat haptoglobin was used as a positive control; molecular weight of precursor prohaptoglobin is 47 kD and cleaved, activated haptoglobin is 37 kD (β chain) and 10 kD (α chain). In (a), serum was collected from a single rat in each group for the time points indicated; shown are data from 3 rats per group. In (b), each lane represents serum from a single rat.