Starfish, Asterias amurensis and Asterina pectinifera, as Potential Sources of Th1 Immunity-Stimulating Adjuvants

Abstract

ABSTRACT. Saponin is the generic name of steroid or triterpene glycosides, and the capacities of some saponins to stimulate both Th1 immune response and production of cytotoxic T cells are useful as vaccine components against intracellular pathogens. Because saponins have been found commonly in starfish, we assessed the potential of starfish, Asterias amurensis and Asterina pectinifera, as adjuvant sources. Crude starfish saponins had hemolytic activities (EC 50 =10 to 100 μg/ml) and thin layer chromatography indicated heterogeneity of their constituents. When starfish saponis were subcutaneously injected into mice with ovalbumin (OVA), OVA-specific IgG, especially IgG2a instead of IgG1 was produced in mouse blood, suggesting starfish saponins stimulated Th1 type immunity and they were potential sources of new adjuvants.

Low-molecular-weight polysaccharides from Agaricus�blazei Murrill modulate the Th1 response in cancer immunity

“…Among the serum antibody IgG subtypes, the IgG1 is a marker dominated by Th2-type immune responses, whereas IgG2b is associated with Th1-type immunity ( 22 , 23 ). To analyze which T cell response is preferentially boosted by ABP-AW1, the serum levels of OVA-specific IgG1 and IgG2b were measured using an ELISA ( Fig.…”

A polysaccharide isolated from Agaricus blazei Murill (ABP-AW1) as a potential Th1 immunity-stimulating adjuvant

“…2) were elevated significantly in the OVA/alum and OVA/ABP-AW1 groups compared with the OVA alone group. The IgG1 subtype is reported to be associated with Th2-dominated immune responses, whereas IgG2b is considered to be a mediator of Th1-type immunity (33). Fig.…”

“…Among the T lymphocytes, T cell responses have been divided in two subclasses, Th1 and Th2. Th1 and Th2 immune response profiles correspond to the activation of two distinct major subsets of T cells characterized by their pattern of cytokine production (29,33), i.e. IL-2, TNF-β and IFN-γ vs. IL-4, IL-5 and IL-10, respectively.…”

“…For example, the ABP-AW1 response may be derived from NK cells stimulating IFN-γ production at the injection site (13,42), which may result in the increased activation of dendritic cells (DCs) that are taking up antigen. In turn, DCs stimulate IFN-γ-producing cells, potentially prolonging the release from the NK cells and T cells, while IFN-γ further substantially enhances IgG2b and IgG2a production by effecting the isotype switching of the B-lymphocytes (33,35). Another possible pathway is the spread of ABP-AW1 into the circulation, whereby ABP-AW1 likely acts systemically on the NK or T cells to stimulate IFN-γ production or the clonal expansion of the T cells.…”

Immunological Adjuvant Activity of Pectinioside A, the Steroidal Saponin from the StarfishPatiria pectinifera

“…Although plants have been the main sources of bioactive saponins, starfish are also a desirable source, because about 400 structurally different saponins have been purified from starfish and their diverse bioactivities such as cytotoxic, hemolytic, ichthyotoxic, antifungal, antiviral and anti-inflammatory activities have been reported [4]. Recently, we have investigated the potential of starfish saponins as immunological adjuvants and found that the crude extract from two common littoral species, Asterias amurensis and Patiria (or Asterina) pectinifera, promoted antibody production when they were subcutaneously injected into mice together with the antigen, ovalbumin (OVA) [5]. Accordingly, in this research, we purified the saponin from P. pectinifera and evaluated its adjuvant activity.…”