Data published in Nutrients indicated that three months of supplementation with three billion colony forming units (CFUs) of Loigolactobacillus coryniformis K8 CECT 5711 (formerly known as Lactobacillus coryniformis) per day resulted in enhanced immune response in elderly people previously infected with the SAR-CoV-2 virus.
The probiotic was also associated with a tendency to improve the postvaccine immune response in subjects over 85 who were not infected with the virus.
“These results add evidence to previous clinical data corroborating the capability of the probiotic strain L. coryniformis K8 to enhance the immune response. Probiotic administration may be a natural and safe strategy to improve the efficacy of vaccines, especially in vulnerable populations such as the elderly,” wrote researchers from the University Clinical Hospital of Santiago de Compostela (SERGAS) and Biosearch Life (a Kerry Company).
The study adds to a growing body of science showing that select probiotic strains may act as adjuvant factors in vaccination. The beneficial bacteria have been studied in combination with different vaccines, notably influenza vaccines.
A 2021 review in Vaccines, concluded: “Since different vaccine platforms are used in COVID-19 vaccine development, we believe that the use of probiotics in this development should be considered. Indeed, probiotic supplementation as adjuvants in boosting immunity and in enhancing vaccine-specific responses could be important in the general population and, in particular, in the elderly and in children, where the effectiveness and duration of immunization could have even more bearing.”
The new study provides evidence that a specific probiotic strain, Loigolactobacillus coryniformis K8 CECT 5711, may indeed boost a response to the Pfizer/ BioNTech COVID-19 vaccine.
The study included 200 nursing home residents 60 or older that had not COVID-19. The subjects were randomly assigned to receive either L. coryniformis K8 or a placebo for three months. All of the participants received the full vaccination schedule for the Pfizer/ BioNTech mRNA vaccine, with the probiotic or placebo starting ten days after the first dose of the vaccine.
Results showed that COVID-19 infections were recorded in 11 people in the K8 group and 8 people in the placebo group, with analysis of these patients showing that people in the K8 group had significantly higher levels of IgG, compared to placebo.
“In the present study, 9.5% of the studied population was infected by the SARS-CoV-2 virus before receiving the second dose of the BNT162b2 mRNA COVID-19 vaccine,” wrote the researchers. “Although the percentage of asymptomatic patients was three times higher in the probiotic group than in the control group, we did not observe significant differences, probably due to the low number of observed cases and, thus, the loss of statistical power.
“In a previous study conducted with the L. coryniformis K8 in the context of the influenza vaccination, the probiotic strain was shown to decrease the incidence of symptoms associated with respiratory infections in an elderly population in a follow-up period of 6 months after the intervention.”
Additionally, among the very old subjects (85 or older) who did not get COVID-19 there was a tendency for increased levels of IgA in the probiotic group, said the researchers.
“In the present study, it was observed that the administration of the probiotic strain tended to increase the IgA response, which could help to increase protection against viral infection and, therefore, may have important clinical applications,” they stated.
2022, 14(1), 228; doi: 10.3390/nu14010228
“Effects of Loigolactobacillus coryniformis K8 CECT 5711 on the Immune Response of Elderly Subjects to COVID-19 Vaccination: A Randomized Controlled Trial”
Authors: A. Fernández-Ferreiro et al.