A study published in 2012 studied the immune response of healthy individuals supplemented with Chlorella. The results showed that Chlorella supplements improve response of normal immune system and help in the activity of cells of "natural killer" immune system in healthy people (Kwak et al., 2012).

The patent US20036551596B2 Ocean Nutrition Canada Company claims a Chlorella extracts based on polysaccharides containing high molecular weight product showed immune activity. These extracts can be administered to mammals to enhance the proliferation of splenocytes and increased production of cytokines such as IL-6, IL-10, IFN-gamma and TNF-alpha.