Planta Med 2023; 89(15): 1483-1492
DOI: 10.1055/a-2156-4653
Biological and Pharmacological Activity
Original Papers

Immulina as an Immunostimulatory Supplement: Formulation and Pharmacological Studies

Yusheng Li
1   Department of Pharmaceutics and Drug Delivery, University of Mississippi, University, Mississippi, USA
Nan Ji
1   Department of Pharmaceutics and Drug Delivery, University of Mississippi, University, Mississippi, USA
Minia Wang
1   Department of Pharmaceutics and Drug Delivery, University of Mississippi, University, Mississippi, USA
Nirmal D. Pugh
2   National Center for Natural Products Research, Research Institute of Pharmaceutical Sciences, University of Mississippi, University, Mississippi, USA
Ikhlas A. Khan
2   National Center for Natural Products Research, Research Institute of Pharmaceutical Sciences, University of Mississippi, University, Mississippi, USA
3   Department of BioMolecular Sciences, University of Mississippi, University, Mississippi, USA
4   Department of Pharmaceutical Sciences, University of Tennessee Health Science Center, Memphis, Tennessee, USA
› Author Affiliations
This work was supported by the Office of Dietary Supplements and the National Center for Complementary and Integrative Health (NCCIH) of the National Institutes of Health [U19AT010838].


Immulina is a commercially available extract of Arthrospira platensis enriched with bacterial lipoproteins that acts as a potent Toll-like receptor 2 agonist. However, the immunostimulatory effect of Immulina is not well understood in vivo. Here, to devise an Immulina formulation suitable for in vivo oral gavage dosing, Immulina nanosuspension was prepared and freeze-dried to yield lyophilized nano-Immulina, which had an average particle size of around 300 nm and fully retained the bioactivity as a Toll-like receptor 2 agonist. Compared to the regular Immulina powder, lyophilized nano-Immulina notably accelerated the dissolution in aqueous media. Immulina nanosuspension was found to stimulate the production of proinflammatory cytokines in murine bone marrow-derived dendritic cells and macrophages. The immune response to Immulina was investigated in healthy mice by longitudinally monitoring the phagocytic activity of circulating neutrophils as a surrogate marker. Following daily oral ingestion of Immulina nanosuspension (10 mg/mouse/day), the phagocytic activity of circulating neutrophils was significantly elevated, suggesting an important mechanism for Immulina to enhance innate immunity.

Supporting Information

Publication History

Received: 28 April 2023

Accepted after revision: 11 August 2023

Article published online:
30 August 2023

© 2023. Thieme. All rights reserved.

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