Ezeorba, T. P. C. | bioRxiv Science

bioRxiv2021

Abated immune responses against recombinant hepatitis-b vaccine by chitin in mice

Abated immune responses against recombinant hepatitis-b protein vaccine by chitin in miceMajority of recombinant protein vaccines employ alum-based adjuvants to boost their immunogenicity in subjects. However, the safe-profiled alum-based adjuvants demonstrate relative ineffectiveness with these recombinant vaccines. This work investigated the adjuvant potential of chitin with recombinant Hepatitis-B protein vaccine (HBsAg) and its possible toxicological effects. Six to eight weeks old female albino mice, which were randomly and equally distributed into five groups were used for this study. Blood collection was done before each vaccination schedule and the samples were used for analysis. Results revealed that IgG and IgG1 titres of mice administered 2 doses of HBsAg-Chitin formulation was significantly (p < 0.05) lower than those administered 3 doses of HBsAg and was not significantly (p > 0.05) higher than those administered 2 doses of HBsAg. However, a progressive increase in the anti-HBsAg titres in mice that received the HBsAg-Chitin formulation was observed as days came by. Activities of alanine and aspartate aminotransferases of all experimental groups, including their liver weights, inferred that the HBsAg-Chitin formulation exert no toxic effect on the liver. The findings of this research revealed that chitin demonstrated a relatively unimpressive adjuvant activity with the recombinant hepatitis-B protein vaccine. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=81 SRC="FIGDIR/small/436808v1_ufig1.gif" ALT="Figure 1"> View larger version (21K): org.highwire.dtl.DTLVardef@981cd6org.highwire.dtl.DTLVardef@8d46bborg.highwire.dtl.DTLVardef@11ec11forg.highwire.dtl.DTLVardef@18ffba_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

bioRxiv2021

Experimental and Molecular Predictions of the Adjuvanticity of Snail Mucin on Hepatitis B Vaccine in Albino Mice

Although aluminum-containing adjuvants are widely used in human vaccination due to their excellent safety profile, they exhibit low effectiveness with many recombinant antigens. This study investigated the adjuvanticity of snail mucin with recombinant Hepatitis B Vaccine (rHBsAg). Twenty-five (25) female mice distributed unbiasedly into 5 groups were used in the study and were administered different rHBsAg/Mucin formulation at 7 days intervals. Blood samples were collected a day following the administration for analysis. The results of liver function and body weight analysis were indications that snail mucin had no adverse effect on the mice. The treatment group (administer mucin and rHBsAg) showed significantly (P<0.05) higher mean titres of anti-HBsAg antibodies when compared with the negative controls and the positive control administered with two doses of rHBsAg. Furthermore, a comparable immune response to positive control administered with three doses rHBaAG was recorded. In silico prediction, studies of the protein-protein interaction of a homology modelled snail mucus protein and HBsAg gave an indication of enhanced HBV antigen-antibody interaction. Therefore, this study has shown that snail mucin possesses some adjuvant properties and enhances immune response towards rHBsAg vaccine. However, there is a need for further molecular dynamics studies to understand its mechanism of action.

immunology↗