Stabilized immunogenic HBc chimer particles

摘要

Disclosed is a recombinant chimer hepatitis B core (HBc) protein molecule up to about 600 amino acid residues in length that (a) contains an HBc sequence of at least about 125 of the N-terminal 183 amino acid residues of the HBc molecule that includes the HBc sequence of residue positions 4 through about 75 and about 85 through about 140 in which one or both cysteine residues at positions 48 and 107 is replaced by another residue, and in which the cysteine at residue position 61 is present; (b) contains a peptide-bonded heterologous amino acid residue sequence at one or more of the N-terminus, in the HBc immunodominant loop between residue positions about 76 through about 85 or the C-terminus of the chimer, and wherein (i) zero to all residues in a sequence in said HBc immunodominant loop are present or replaced and said heterologous amino acid residue sequence comprises one to about 245 amino acid residues that constitute an Immunogen or a sequence of 1 to about 40 residues that constitutes an anti-antigen or a chemically-reactive linker residue for a conjugated hapten; or (ii) the sequence of HBc at positions 76 through 85 is present and free from deletions and heterologous residues; or (iii) one or more of residues 76 through 85 is absent or replaced; (c) contains one or both of (i) one to three cysteine residues at an amino acid position of the chimer molecule corresponding to amino acid position -20 to about +1 from the N-terminus of the HBc sequence of SEQ ID NO:1 [N-terminal cysteine residue(s)] in a sequence other than that of the HBc precore sequence and (ii) one to three cysteine residues toward the C-terminus of the chimer molecule [C-terminal cysteine residue(s)]; said chimer molecule (i) containing up to about 5 percent substituted amino acid residues in the HBc sequence relative to SEQ ID NO:1, and (ii) self-assembling into particles that exhibit a ration of absorbance at 280 nm to 260 nm of about 0.9 to about 1.7 after expression.