3.6. Antigen-specific splenocyte proliferation
Splenocyte proliferation was evaluated after stimulation with ORF8. As shown in Fig. 3E, the PI value of the ORF8-CRM group (0.64) was higher than that of the ORF8 group (0.06) (P<0.05) and lower than that of the ORF8/AL group (1.48) (P<0.05). Thus, conjugation with CRM197could stimulate the ORF8-specific splenocyte proliferation, and the ability was lower than administration with aluminum adjuvant. The PI value of the ORF8-PEG group (3.20) was the highest among the five groups. This indicated that slef-conjugation with 8-arm PEG was more effective than aluminum adjuvant and CRM197 conjugation to enhance the splenocyte proliferation.