Serum titers of lgG (A), lgG1 (B) and lgG2 (C) in mice immunized with recombinant bacille calmette-guerins (rBCGs), including rBCG-1173:A, rBCG-1173:E, rBCG-1173:I, rBCG-1173:C, rBCG-1173:G, rBCG-1173:AE, rBCG-1173:IE, rBCG-1173:GC, rBCG-1173:GE and rBCG-1173:GCE. Mice immunized with BCG-1173 and BCG-1173:361 were considered to be the control groups. *P < 0.05 vs. BCG-1173, rBCG-1173:361, rBCG-1173:A, rBCG-1173:C, rBCG-1173:E, rBCG-1173:I and rBCG-1173:G group.