CpG-Containing Oligodeoxynucleotides and Freund Adjuvant in Combination with Alum Augment the Production of Monoclonal Antibodies Against Recombinant HBsAg

Abstract

Background: Adjuvants are essential to potentiate the immune response to inoculated antigens and play a central role in vaccine development. Alum is generally used as a classic adjuvant, although it does not stimulate proper immunity, and some of the immunized subjects have low or no antibody response. Efforts have been continued to find more efficient adjuvants for better antibody responses. In the present study, the efficacy of three formulations of adjuvants, i.e. Cysteine p Guanine Oligodeoxynucleotide (CpG ODN), alum, and Freund, in the production of monoclonal anti Hepatitis B Surface Antigen (HBsAg) antibodies was investigated.
 Methods: To immunize mice, regular hepatitis B vaccine containing recombinant HBsAg and alum was used with CpG ODN or Freund adjuvants, and splenocytes of hyperimmunized mice were fused with murine myeloma Sp2/0 cells. Positive hybridomas were selected by Enzyme-Linked Immunosorbent Assay (ELISA) using HBsAg as coating antigen followed by a limited dilution process.
 Results: The results showed that by using all three formulations of adjuvants, monoclonal antibody (mAb) specific to HBsAg was successfully generated. It was also found that the mice immunized with (HBsAg + Alum) + CpG had the highest concentration of antibody production in serum and hybridoma supernatants as well as positive clones. Based on these findings, the addition of CpG ODN also induced a higher antibody response compared with Complete Freund’s Adjuvant (CFA).
 Conclusion: Results of this study showed that CpG and Freund adjuvants could be efficient partners for alum in the immunization period of the process of monoclonal antibody production.

Comparison of the effectiveness four years after Homo/Hetero prime-boost with 10 μg HP and 20 μg CHO recombinant hepatitis B vaccine at 1 and 6 months in maternal HBsAg-negative children

“…The most commonly used adjuvant was Al(OH)3, Cysteine p Guanine Oligodeoxynucleotide (CpG-ODN) is a new adjuvant that has been developed in recent years. A recent study showed that CpG-ODN induced a higher antibody response compared to Al(OH)3 ( 23 ). The adjuvants for 10 μg HepB-HP and 20 μg HepB-CHO were the same in our study, which were mainly Al(OH)3 and sodium chloride.…”

Aluminum Adjuvants—‘Back to the Future’

“…Negatively charged CpG ODNs readily adsorb to AH, although phosphate ions inhibited optimal adsorption in a concentration-dependent manner [ 143 ]. Several reports on the AH–CpG ODN combination adjuvant have been performed using different antigens ranging ovalbumin [ 144 ], SARS-CoV-2 RBD subunit [ 145 ], and hepatitis B surface antigen (HbsAg) [ 146 ]. This combination adjuvant will be discussed more in depth in an accompanying review in this journal (Dynavax).…”