Fig. 1.

Purification of rHIgM12 to >97 %. IgM was isolated from culture supernatant using a three-step purification protocol. a shows a flow diagram of the three-step purification protocol. b shows the final eluate from the third step, i.e., separation on a Sephacryl S-300 HR column in the presence of 10 mM NaOH and 150 mM NaCl (pH 7.0). c shows an SDS-PAGE gel of the following: lane 1—molecular weight markers, lanes 2 and 3—20-μl samples of the peak fraction showed in b. The IgM heavy chain (H, 75 kDa) and light chain (L, 25 kDa) are shown