Utility of fatty acid profile and in vitro immune cell activation for chemical and biological standardization of Arthrospira/Limnospira

Abstract

Commercially cultivated Limnospira (species formerly classified to genus Arthrospira) is a popular food/supplement consumed by millions of people worldwide for health benefits. The objective of the current research was to advance the standardization technology for Limnospira. Quantitative methods were established to detect fatty acids as potential chemical markers and immune-enhancing activity. Analysis of 20 different batches of biomass obtained from one commercial grower demonstrated that there was a statistically significant relationship between the sum of two fatty acids (linoleic and γ-linolenic) and Toll-like receptor (TLR)2/TLR1-dependent activation (R2 = 0.48, p = 0.0007). Investigation of 12 biomass samples sourced from growers in 10 different countries demonstrated that fatty acid content was again significantly correlated with biological activity (R2 = 0.72, p = 0.0005) and the content of fatty acids varied by twofold and activity by 12.5-fold. This large variation between different samples confirms the need to use the present standardization methods to ensure consistent and properly characterized biomass for consumers and for future scientific research.

Immulina as an Immunostimulatory Supplement: Formulation and Pharmacological Studies

“…Immulina Immulina is recognized by TLR2/TLR1 without losing any activity as a TLR2 ligand. In HEK-Blue hTLR2 KO-TLR1/6 cells [9], a parental cell line for HEK-Blue hTLR2-TLR1 cells that harbor TLR1 knockout, none of the Immulina samples induced the SEAP activity above the background level, confirming that the TLR2/TLR1 heterodimer is essential for the bioactivity of the regular and nano-sized Immulina. Together, the above findings indicate that the nanoformulation of Immulina can overcome the solubility limitation while retaining the full bioactivity as a TLR2 agonist.…”

“…Bacterial lipoproteins evoke innate immune responses by functioning as ligands of the mammalian TLR2 [22]. HEK-Blue hTLR2-TLR1 cells, which encode SEAP as a reporter gene under the control of TLR2/TLR1-mediated NF-κB/AP-1 signaling, were employed to quantify the bioactivity of Immulina as a TLR2 agonist [9]. The expression of SEAP in response to TLR2/TLR1 stimulation is indicated by its enzymatic activity in converting an alkaline phosphatase substrate to the product (the absorbance at 620 nm, A 620 nm ).…”

“…Immulina triggers TLR2-mediated activation of NF-κB signaling, resulting in the induction of proinflammatory cytokines [8]. Although the precise chemical structures of Braunʼs lipoproteins in Immulina remain to be elucidated, a recent quantitative fatty acid profiling study shows that palmitic, linoleic, and γ-linolenic acids are the dominant lipid moieties in Immulina, and the sum of linoleic and γ-linolenic acids is correlated with the TLR2 agonistic activity of Immulina [9]. The immunostimulatory effect of Immulina has been demonstrated in a murine model of influenza A virus (H1N1) infection, in which daily ingestion of Immulina that started prophylactically 30 days prior to the inoculation of the H1N1 virus substantially reduced several pathological parameters caused by the H1N1 infection [10].…”

Histomorphometric lung density evaluation of Immulina treatment using a murine influenza pneumonia model

“…The Immulina™ test material used is a crude extract of Arthrospira/Limnospira that was provided by ChromaDex (lot 2290020). Taxonomic identification of the raw material was previously performed using morphological examination and sequence analysis and determined to be Limnospira fusiformis 8 . Immulina is standardized using a bioassay employing THP‐1 human monocytes that quantitates potency to ensure batch to batch consistency of activity.…”

“…Photomicrographs were taken with an AmScope MU1403 camera (AmScope, Irvine, CA) using the associated software‐based program. A detailed description of the mouse pneumonia model was published previously by other investigators 8 …”