Antibody binding to hepatitis b virus surface antigen and application of antibody

An antibody or an antigen-binding fragment thereof specifically binding to hepatitis B virus surface antigen (HBsAg), comprising a heavy chain variable region (VH) sequence and a light chain variable region (VL) sequence, wherein:

• the heavy chain variable region comprises complementarity determining region (CDR) amino acid sequences as shown below:
• HCDR1:
• (SEQ ID NO:
• 33)
• X1YX3FX5X6X7Y,
• HCDR2:
• (SEQ ID NO:
• 34)
• X11NX13X14X15X16X17X18,
• and
• HCDR3:
• (SEQ ID NO:
• 35)
• ARDX21WX23X24X25X26DX28YGMDX33;
• the light chain variable region comprises CDR amino acid sequences as shown below:
• LCDR1:
• (SEQ ID NO:
• 36)
• X34X35X36SX38X39,
• LCDR2:
• (SEQ ID NO:
• 37)
• X40X41X42,
• and
• LCDR3:
• (SEQ ID NO:
• 38)
• QQSYSTPLX51;
• wherein:
• X1 is selected from G or A, X3 is selected from T, A or S, X5 is selected from T, A or I, X6 is selected from G, A, Y or D, X7 is selected from Y or A, X11 is selected from I or A, X13 is selected from P or A, X14 is selected from N, A or Y, X15 is selected from S, A or N, X16 is selected from G or A, X17 is selected from G or A, X18 is selected from T or A, X21 is selected from L, V or A, X23 is selected from N, Q or A, X24 is selected from D, Q or A, X25 is selected from D, G or A, X26 is selected from V, G or A, X28 is selected from Y or A, X33 is selected from V or A, X34 is selected from Q or A, X35 is selected from S or A, X36 is selected from I, A or V, X38 is selected from T, A or S, X39 is selected from Y or A, X40 is selected from A, G, D, T or S, X41 is selected from A or S, X42 is selected from A or S, and X51 is selected from T or A.