Effect and Tolerability of a Nutritional Supplement Based on a Synergistic Combination of β-Glucans and Selenium- and Zinc-Enriched Saccharomyces cerevisiae (ABB C1®) in Volunteers Receiving the Influenza or the COVID-19 Vaccine: A Randomized, Double-Blind, Placebo-Controlled Study

Abstract

A single-center, randomized, double-blind, placebo-controlled study was conducted in 72 volunteers who received a synergistic combination of yeast-based ingredients with a unique β-1,3/1,6-glucan complex and a consortium of heat-treated probiotic Saccharomyces cerevisiae rich in selenium and zinc (ABB C1^®) or placebo on the next day after getting vaccinated against influenza (Chiromas^®) (n = 34) or the COVID-19 (Comirnaty^®) (n = 38). The duration of treatment was 30 and 35 days for the influenza and COVID-19 vaccine groups, respectively. Mean levels of CD4+T cells increased from 910.7 at baseline to 1000.2 cells/µL after the second dose of the COVID-19 vaccine in the ABB C1^® group, whereas there was a decrease from 1055.1 to 929.8 cells/µL in the placebo group. Changes of CD3+T and CD8+T lymphocytes showed a similar trend. In the COVID-19 cohort, the increases in both IgG and IgM were higher in the ABB C1^® supplement than in the placebo group. Serum levels of selenium and zinc showed a higher increase in subjects treated with the active product than in those receiving placebo. No serious adverse events related to ABB C1^® or tolerance issues were reported. The study findings validate the capacity of the ABB C1^® product to stimulate trained immunity.

Keywords: COVID-19 vaccine; Saccharomyces cerevisiae; influenza vaccine; nutritional supplementation; selenium; trained immunity; zinc; β-1,3/1,6-glucan complex.

Figure 1

(A) In the influenza vaccine cohort, participants were given supplementation with ABB C1^® or placebo and blood samples for analyses were taken at baseline and at days 7 and 30 (end of study). (B) In the COVID-19 vaccine cohort, participants were given supplementation with ABB C1^® or placebo and received a first vaccine dose (day 1) and a second vaccine dose (day 21) and were followed for 35 days, with blood samples for analyses taken at baseline and at days 7, 21, and 35 (end of study).

Figure 2

Time course of blood levels of CD4+T lymphocytes in the COVID-19 vaccine cohort. In the ABB C1^® supplementation group, CD4+T lymphocytes increased as compared with baseline and after the second vaccine dose, whereas, in the placebo group, there was a decrease as compared with baseline.

Figure 3

Time course of blood levels of CD4+T lymphocytes in the influenza vaccine cohort. There was an increase in CD+T lymphocytes at the end of the study (day 30) as compared with baseline in both supplemented groups, but the magnitude of the increase was greater in the ABB C1^® supplement group than in the placebo group.

Figure 4

Time course of serum levels of IgG and IgM in the COVID-19 cohort during the study.

Figure 5

Changes of mean values of selenium and zinc concentrations in the COVID-19 and influenza vaccine cohorts at the end of the study as compared with baseline in the active supplementation (ABB C1^®) and placebo (standard of care) groups.