Immunomodulatory Effect of Rhaphidophora korthalsii on Natural Killer Cell Cytotoxicity

Area of Science:

• Pharmacology
• Immunology
• Ethnobotany

Background:

• Natural products are a source of novel therapeutic agents.
• Rhaphidophora korthalsii is a plant with traditional medicinal uses.
• Understanding its immunomodulatory potential requires in vivo investigation.

Purpose of the Study:

• To evaluate the in vivo immunomodulatory effects of Rhaphidophora korthalsii ethanolic leaf extract.
• To assess the extract's impact on immune cell proliferation, T/NK cell populations, and splenocyte cytotoxicity.
• To compare the duration of the extract's stimulatory effect with recombinant interleukin-2 (rIL-2).

Main Methods:

• BALB/c mice were administered ethanolic extract of Rhaphidophora korthalsii leaves daily for 5 days.
• Immune cell proliferation, T/NK cell phenotyping, and splenocyte cytotoxicity were assessed.
• Plasma cytokine levels (IL-2 and IFN-γ) and splenocyte cytotoxicity against Yac-1 cells were measured on days 5 and 15.

Main Results:

• High concentrations of the extract significantly stimulated immune cell proliferation and splenocyte cytotoxicity.
• The extract increased peripheral blood NK cell populations and plasma levels of IL-2 and IFN-γ.
• The observed immunostimulatory effects persisted until day 15, outlasting the effect of rIL-2.

Conclusions:

• Ethanolic extract of Rhaphidophora korthalsii leaves exhibits significant in vivo immunomodulatory activity.
• The extract demonstrates potential as a natural immunostimulator with sustained effects.
• Further research, including fractionation and purification, is warranted to identify active compounds.