Enhancement of Natural Killer Cell Activity in Healthy Subjects by Immulina®, a Spirulina Extract Enriched for Braun-Type Lipoproteins

Abstract

Immulina®, a commercial extract of Arthrospira (Spirulina) platensis is a potent activator of THP-1 monocytes and CD4+ T cells in vitro and enhances several immunological functions in mice. We further characterized Immulina® by determining that Braun-type lipoproteins are responsible for a major portion of the in vitro monocyte activation exhibited by this material. In order to understand the effect of Immulina® on NK cell activity, a pilot study was conducted on ten healthy North American individuals who supplemented their diet with Immulina® (400 mg/day) for seven days. We observed a 40 % average increase in the killing of K562 tumor cells by NK cells (p < 0.01) after Immulina® supplementation. In a separate placebo-controlled, crossover study involving 11 healthy Danish subjects, we observed increased mRNA expression of the NK cell marker NKG2D by 37 % (p = 0.02) and by 55 % (p = 0.0003) after administration of Immulina® (200 mg and 400 mg per day, respectively) for seven days. The mRNA expression of the NK- and T-cell marker perforin increased by 75 % (p = 0.008) after administration of 400 mg Immulina® per day. Both markers displayed significant dose-dependent effects (p = 0.0003 and p = 0.02, respectively). The ratio between CD56^bright and CD56^dim NK cells was not affected by Immulina® administration. In summary, two independent studies showed enhancement of NK cell activity following administration of Immulina® for seven days.

Key words

Arthrospira platensis - Phormidiaceae - Spirulina - natural killer (NK) cells - Braun‐type lipoproteins - Immulina - clinical trial

References

• 1 Ciferri O. Spirulina, the edible microorganism.  Microbiol Rev. 1983;  47 551-578
• 2 Kay R A. Microalgae as food and supplement.  Crit Rev Food Sci Nutr. 1991;  30 555-573
• 3 Qureshi M A, Garlich J D, Kidd M T. Dietary Spirulina platensis enhances humoral and cell-mediated immune functions in chickens.  Immunopharmacol Immunotoxicol. 1996;  18 465-476
• 4 Al-Batshan H A, Al-Mufarrej S I, Al-Homaidan A A, Qureshi M A. Enhancement of chicken macrophage phagocytic function and nitrite production by dietary Spirulina platensis.  Immunopharmacol Immunotoxicol. 2001;  23 281-289
• 5 Zhang H Q, Lin A P, Sun Y, Deng Y M. Chemo- and radio-protective effects of polysaccharide of Spirulina platensis on hemopoietic system of mice and dogs.  Acta Pharmacol Sin. 2001;  22 1121-1124
• 6 Hayashi O, Hirahashi T, Katoh T, Miyajima H, Hirano T, Okuwaki Y. Class specific influence of dietary Spirulina platensis on antibody production in mice.  J Nutr Sci Vitaminol (Tokyo). 1998;  44 841-851
• 7 Pugh N, Ross S A, ElSohly H N, ElSohly M A, Pasco D S. Isolation of three new polysaccharide preparations with potent immunostimulatory activity from Spirulina platensis, Aphanizomenon flos-aquae and Chlorella pyrenoidosa.  Planta Med. 2001;  67 737-742
• 8 Grzanna R, Polotsky A, Phan P V, Pugh N, Pasco D, Frondoza C G. Immolina, a high-molecular-weight polysaccharide fraction of Spirulina, enhances chemokine expression in human monocytic THP-1 cells.  J Altern Complement Med. 2006;  12 429-435
• 9 Balachandran P, Pugh N D, Ma G, Pasco D S. Toll-like receptor 2-dependent activation of monocytes by Spirulina polysaccharide and its immune enhancing action in mice.  Int Immunopharmacol. 2006;  6 1808-1814
• 10 Løbner M, Walsted A, Larsen R, Bendtzen K, Nielsen C H. Enhancement of human adaptive immune responses by administration of a high-molecular-weight polysaccharide extract from the cyanobacterium Arthrospira platensis.  J Med Food. 2008;  11 313-322
• 11 Herberman R B, Ortaldo J R. Natural killer cells: their roles in defenses against disease.  Science. 1981;  214 24-30
• 12 Talmadge J E, Meyers K M, Prieur D J, Starkey J R. Role of NK cells in tumour growth and metastasis in beige mice.  Nature. 1980;  284 622-624
• 13 Hirahashi T, Matsumoto M, Hazeki K, Saeki Y, Ui M, Seya T. Activation of the human innate immune system by Spirulina: augmentation of interferon production and NK cytotoxicity by oral administration of hot water extract of Spirulina platensis.  Int Immunopharmacol. 2002;  2 423-434
• 14 Pasco D S, Pugh N D C. Immunostimulatory composition comprising lipoprotein in microalgae extract. U.S. Patent Application Number 12/440552. 2010
• 15 Eagle R A, Trowsdale J. Promiscuity and the single receptor: NKG2D.  Nat Rev Immunol. 2007;  7 737-744
• 16 Kelly-Rogers J, Madrigal-Estebas L, O'Connor T, Doherty D G. Activation-induced expression of CD56 by T cells is associated with a reprogramming of cytolytic activity and cytokine secretion profile in vitro.  Hum Immunol. 2006;  67 863-873
• 17 Chávez-Galán L, Arenas-Del Angel M C, Zenteno E, Chávez R, Lascurain R. Cell death mechanisms induced by cytotoxic lymphocytes.  Cell Mol Immunol. 2009;  6 15-25
• 18 Cooper M A, Fehniger T A, Caligiuri M A. The biology of human natural killer-cell subsets.  Trends Immunol. 2001;  22 633-640
• 19 Aliprantis A O, Weiss D S, Radolf J D, Zychlinsky A. Release of Toll-like receptor-2-activating bacterial lipoproteins in Shigella flexneri culture supernatants.  Infect Immun. 2001;  69 6248-6255
• 20 Hashimoto M, Asai Y, Ogawa T. Separation and structural analysis of lipoprotein in a lipopolysaccharide preparation from Porphyromonas gingivalis.  Int Immunol. 2004;  16 1431-1437
• 21 Hashimoto M, Tawaratsumida K, Kariya H, Aoyama K, Tamura T, Suda Y. Lipoprotein is a predominant Toll-like receptor 2 ligand in Staphylococcus aureus cell wall components.  Int Immunol. 2006;  18 355-362
• 22 Wu H C. Biosynthesis of lipoproteins. Neidhardt FC, Curtiss R, Ingraham JL, Lin ECC, Low KB, Magasanik B, Reznikoff WS, Riley M, Schaechter M, Umbarger HE Escherichia coli and Salmonella: cellular and molecular biology, 2nd ed. Washington DC; ASM Press 1996: 1005-1014
• 23 Muhlradt P F, Meyer H, Jansen R. Identification of S-(2,3-Dihydroxypropyl) cysteine in a macrophage-activating lipopeptide from Mycoplasma fermentans.  Biochemistry. 1996;  35 7781-7786
• 24 Bartizal K F, Salkowski C, Balish E. The influence of a gastrointestinal microflora on natural killer cell activity.  J Reticuloendothel Soc. 1983;  33 381-390
• 25 Bartizal K F, Salkowski C, Pleasants J R, Balish E. The effect of microbial flora, diet, and age on the tumoricidal activity of natural killer cells.  J Leukoc Biol. 1984;  36 739-750
• 26 Takeda K, Okumura K. Effects of a fermented milk drink containing Lactobacillus casei strain Shirota on the human NK-cell activity.  J Nutr. 2007;  137 791S-793S
• 27 Gill H S, Rutherfurd K J, Cross M L, Gopal P K. Enhancement of immunity in the elderly by dietary supplementation with the probiotic Bifidobacterium lactis HN0191.  Am J Clin Nutr. 2001;  74 833-839
• 28 Ezendam J, van Loveren H. Probiotics: immunomodulation and evaluation of safety and efficacy.  Nutr Rev. 2006;  64 1-14
• 29 Chiang B L, Sheih Y H, Wang L H, Liao C K, Gill H S. Enhancing immunity by dietary consumption of a probiotic lactic acid bacterium (Bifidobacterium lactis HN019): optimization and definition of cellular immune responses.  Eur J Clin Nutr. 2000;  54 849-855
• 30 Sheih Y H, Chiang B L, Wang L H, Liao C K, Gill H S. Systemic immunity-enhancing effects in healthy subjects following dietary consumption of the lactic acid bacterium Lactobacillus rhamnosus HN001.  J Am Coll Nutr. 2001;  20 149-156
• 31 Leyer G J, Li S, Mubasher M E, Reifer C, Ouwehand A C. Probiotic effects on cold and influenza-like symptom incidence and duration in children.  Pediatrics. 2009;  124 e172-e179
• 32 Akao Y, Ebihara T, Masuda H, Saeki Y, Akazawa T, Hazeki K, Hazeki O, Matsumoto M, Seya T. Enhancement of antitumor natural killer cell activation by orally administered Spirulina extract in mice.  Cancer Sci. 2009;  100 1494-1501
• 33 Mrozek E, Anderson P, Caligiuri M A. Role of interleukin-15 in the development of human CD56⁺ natural killer cells from CD34⁺ hematopoietic progenitor cells.  Blood. 1996;  87 2632-2640
• 34 Yu H, Fehniger T A, Fuchshuber P, Thiel K S, Vivier E, Carson W E, Caligiuri M A. Flt3 ligand promotes the generation of a distinct CD34⁺ human natural killer cell progenitor that responds to interleukin-15.  Blood. 1998;  92 3647-3657