Influenza/SARS-CoV-2 Omicron Subunit Combined Vaccine Induced High
Levels of IgG1 and IgG2a Antibodies in
Mice
Endpoint titers of HA or SARS-CoV-2 Omicron BA.5 S-RBD-specific
IgG1 and IgG2a in immunized mouse sera
on day 21 and 35 were also detected by ELISA. As shown in Figure 3A, a
quite high level of HA-specific IgG1 was observed in
mice immunized with HA with no significant difference between the HA and
HA+SARS-CoV-2 Omicron BA.5 S immunized groups. The level of IgG1 was
significantly increased on day 35 in mice immunized with HA and
HA+SARS-CoV-2 Omicron BA.5 S, respectively. As shown in Figure 3B, a
high level of SARS-CoV-2 Omicron BA.5 S-RBD-specific
IgG1 was observed in mice immunized with SARS-CoV-2
Omicron BA.5 S. The level of IgG1 was significantly
increased on day 35 in mice immunized with SARS-CoV-2 Omicron BA.5 S and
HA+SARS-CoV-2 Omicron BA.5 S, respectively. As shown in Figure 2C and
2D, HA or SARS-CoV-2 Omicron BA.5 S-RBD-specific IgG2ain immunized mouse sera on day 21 was detected. Moreover, the level of
IgG2a was significantly increased on day 35 in mice
immunized with HA and SARS-CoV-2 Omicron BA.5 S, respectively.
Importantly, the influenza/SARS-CoV-2 Omicron subunit combined vaccine
induced balanced Th1/Th2 cellular immune
response in BALB/c mice.