Isolation of Three High Molecular Weight Polysaccharide Preparations with Potent Immunostimulatory Activity fromSpirulina platensis,Aphanizomenon flos-aquaeandChlorella pyrenoidosa

Abstract

This research describes the identification of three new high molecular weight polysaccharide preparations isolated from food-grade microalgae that are potent activators of human monocytes/macrophages: "Immulina" from Spirulina platensis, "Immunon" from Aphanizomenon flos-aquae, and "Immurella" from Chlorella pyrenoidosa. These polysaccharides are structurally complex and have estimated molecular weights above ten million daltons. All three polysaccharides are highly water soluble and comprise between 0.5 % and 2.0 % of microalgal dry weight. Immunostimulatory activity was measured using a transcription factor-based bioassay for nuclear factor kappa B (NF-kappa B) activation in THP-1 human monocytes/macrophages. Using this system the EC(50) values for these microalgal polysaccharides are between 20 and 110 ng/ml (about 10pM). THP-1 activation was confirmed by measuring immune cytokine mRNA induction using reverse transcriptase-polymerase chain reaction (RT-PCR). Each polysaccharide substantially increased mRNA levels of interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha). These polysaccharides are between one hundred and one thousand times more active for in vitro monocyte activation than polysaccharide preparations that are currently used clinically for cancer immunotherapy.

Immunomodulatory activity of acidic polysaccharides isolated from Tanacetum vulgare L.

“…For example, high M r polysaccharides from Aloe vera increased NF-κB directed luciferase expression in THP-1 cells [46]. Likewise, high M r polysaccharides from Spirulina platensis, Aphanizomenon flos-aquae, and Chlorella pyrenoidosa were found to activate NF-κB, leading to increased immune cytokine mRNA levels [47]. It is well known the activation of NF-κB plays a critical role in the transcriptional regulation of TNF-α and inducible NO synthase (iNOS) genes [45].…”

Characterization of polysaccharides from Hypnea spinella (Gigartinales) and Halopithys incurva (Ceramiales) and their effect on RAW 264.7 macrophage activity

“…In addition, high molecular weight polysaccharide preparations isolated from food-grade microalgae have been described as potent activators of human monocytes/macrophages: "Immulina" from Spirulina platensis, "Immunon" from Aphanizomenon flos-aquae, and "Immurella" from Chlorella pyrenoidosa (Pugh et al 2001). Each of these polysaccharides substantially increased mRNA levels of IL-1β and TNF-α, and they are between 100 and 1,000 times more active for in vitro monocyte activation than polysaccharide preparations that are currently used clinically for cancer immunotherapy.…”

Potential complementarity of high-flavanol cocoa powder and spirulina for health protection

“…The versatile heath protection associated with statin therapy or angiotensin II antagonism -seemingly greater than would be predicted from their hypolipidemic or antihypertensive activities -may be largely attributable to their down-regulatory impacts on the NADPH oxidase activity of certain tissues. 60 Spirulina also is a source of polysaccharide that has immunostimulant activity (reflecting the activation of TLR2 receptors on macrophages), [61][62][63] and is very rich in zeaxanthin, a dietary carotenoid that has been linked to decreased risk for macular degeneration. 64 A recent open clinical trial reports worthwhile reductions in blood pressure and improvements in blood lipid profile in healthy volunteers receiving 4.5 g spirulina daily; this suggests that spirulina-bound PCB may have good oral bioavailability in humans.…”