The Use of Xanthan Gum as Vaccine Adjuvant: An Evaluation of Immunostimulatory Potential in BALB/c Mice and Cytotoxicity In Vitro.

Rodrigo Andrade Schuch,Angelita da Silveira Moreira,Thaís Larré Oliveira,Guilherme Roig Inda,Daiane Drawanz Hartwig,Leonardo Garcia Monte,Thaís Farias Collares,Claire Tondo Vendruscolo,Odir Antonio Dellagostin

doi:10.1155/2017/3925024

Rodrigo Andrade Schuch, Angelita da Silveira Moreira + Show 7 more

Open Access

https://doi.org/10.1155/2017/3925024

Copy DOI

Abstract

The successful production of new, safe, and effective vaccines that generate immunological memory is directly related to adjuvant feature, which is responsible for increasing and/or modulating the immune response. Several compounds display adjuvant activity, including carbohydrates. These compounds play important roles in the immune response, as well as having biocompatible properties in vaccine formulations. One such carbohydrate is xanthan gum, a polysaccharide that is produced by the plant-pathogenic bacterium Xanthomonas spp., which has adjuvant attributes. This study evaluated the immune response induced by xanthan gum associated with ovalbumin in BALB/c mice, which were subcutaneously immunized, in terms of antibody production (IgG1, IgG2a, IgG2b, and IgG3), and assessed the levels of IFN-γ in the splenocyte culture using indirect ELISA. Furthermore, we investigated in vitro cytotoxicity of xanthan in the embryo fibroblasts cell line of the NIH/3T3 mouse by MTT assay and propidium iodide uptake assay. The mice immunized with ovalbumin plus xanthan gum exhibited higher antibody IgG1 responses than control groups. Furthermore, the xanthan polysaccharide was capable of increasing the immunogenicity of antigens by producing IFN-γ and did not exhibit cytotoxicity effects in NIH/3T3 mouse fibroblast cells, considered a promising candidate for vaccine adjuvant.

Highlights

Vaccine adjuvants are compounds used to improve the immunogenicity of a particular antigen [1]
All experiments were conducted in accordance with the regulations, policies, and principles of the National Council for Animal Experiments Control in Brazil (CONCEA) and the manual established by the Ethics Committee for Animal Experimentation of the Federal University of Pelotas (UFPel), approved under Protocol number 3418
The xanthan gum used in this experiment had moisture, ash, nitrogen, acetyl, pyruvate, and good viscosity in accordance with the recommendations by the FAO and Burlock for xanthan used as food additives [22, 23]

Summary

Introduction

Vaccine adjuvants are compounds used to improve the immunogenicity of a particular antigen [1]. Aluminumbased mineral salts, approved for human use by the US Food and Drug Administration (FDA), are the most widely used vaccine adjuvants since 1920, inducing predominantly antibody responses. The discovery of new adjuvants is crucial for the development of vaccines that require a cellmediated response [2, 3]. Modern adjuvant development is based on enhancing and shaping vaccine-induced responses without compromising safety by selectively adding welldefined molecules, formulations, or both [4]. New adjuvant formulations are in advanced stages of development and licensing. Preclinical trials show the lack of basic safety requirements for humans use [5,6,7,8,9]

Methods

Results

Conclusion