The Corrective Effect of Fucoidan, a Sulfated Polysaccharide Extracted from Brown Algae Fucus evanescens, in the Formation of a Specific Immune Response Against Seasonal Influenza Viruses in the Elderly

The article establishes the particularities of immune system dysfunction in the elderly during formation of a specific immune response to vaccination with a seasonal influenza vaccine depending on the level of seroconversion. The corrective effect of fucoidan — a sulfated polysaccharide extracted from brown algae Fucus evanescens — was shown in the formation of a spe­cific immune response, accompanied by an increase in the expression of the activation molecules CD69 and CD86 on mono­cytes, a decrease in the expression density of CD20 on B-lymphocytes, and an increase in the relative content of memory cells (CD4 + CD45RO + -T-lymphocytes and cytotoxic CD8 + CD45RO + -T-lymphocytes). Fucoidan extracted from the brown algae Fucus evanescens of the Sea of Okhotsk can be used to increase the effectiveness of seasonal influenza vacci­nation in the elderly.