Figure 4

Analysis of serum response to GST-gp120_CN54 fragments by Western blot. Expression of each GST fusion protein was induced for 3 hrs and the equivalent of 50 μl of the culture fractionated on 10% SDS-PAGE before the transfer. Lanes 1–5 are the GST-gp120_CN54 fusion proteins 1 to 5 with the origin of the gp120_CN54 fragments as shown in additional file 2. Lane 6 is GST only (western blot reaction at 26 kDa and 54 kDa in panel A are monomer and dimer of GST respectively). The GST serum (Sigma) was used at 1:5000, serum dilutions for blots B-D were as described for figure 3.