A Japanese team identified the molecular mechanism of the human immune capacity of Spirulina by analysing blood cells of volunteers with pre- and post-oral administration of hot water extract ofSpirulina platensis. IFN-γ production and Natural Killer (NK) cell damage were increased after administration of the microalga extracts to male volunteers [13].
In a recent double-blind, placebo-controlled study from Turkey evaluating the effectiveness and tolerability of Spirulina for treating patients with allergic rhinitis, Spirulina consumption significantly improved the symptoms and physical findings compared with placebo (), including nasal discharge, sneezing, nasal congestion and itching [14].
It is well understood that deficiency of nutrients is responsible for changes in immunity, which manifests as changes in production of T-cells, secretory IgA antibody response, cytokines and NK-cell activity. The above studies suggest that Spirulina may modulate the immune system by its role in covering nutritional deficiencies.