Detection of anti-preS1 antibodies for recovery of hepatitis B patients by immunoassay

Figure 3 Expression and intracellular location of preS1(21-119 aa) in E. coli. BL21(DE3)plysS cells. Protein samples were subjected to 15% SDS-PAGE and stained with Commassia brilliant blue (A), and the duplicate gel was electroblotted onto a nitrocellulose membrane for western analysis (B). Lane M: molecular mass standards. Lane 1-2 are culture lysates of uninduced BL21 cells (lane 1) and induced BL21 cells (lane 2). Lane 3, 4: Supernatant (soluble) and precipitate (insoluble) fractions, respectively; Lane5: purified fusion protein by Ni²⁺-IDA-sepharose 6B.