Fig. 6

Serum cross-reactivity with A35R homologs of OPXV strains. A Amino acid sequence alignment of MPXV A35R protein, its homologs from VACV (red), VACV-like (orange), CPXV (yellow), CPXV-like-1 (green), CPXV-like-2 (purple) and CPXV-like-3 (blue) strains. The different amino acid residues (compared to MPXV A35R) are labeled in yellow. Two recombinant A35R homologous proteins, A35R-h1 and A35R-h2, were expressed for serologic ELISA. The A35R-h1 recombinant protein shared the same amino acid sequence with the A35R homologs of five VACV strains (the red arrow line). The A35R-h2 recombinant protein shared the same amino acid sequence with the A35R homologs of one CPXV, five CPXV-like-1, and eight CPXV-like-2 strains (the blue arrow lines). B-E Serologic ELISA AUC values for two VACV-infected donors (B), eight donors with low reactivity against MPXV proteins (C), and the top 13 antibody responders against MPXV proteins (D and E). Red, individuals born before 1980; blue, individuals born after 1980; orange, individuals recovered from previous VACV infection