Etlingera rubroloba A.D. Poulsen Fruits as a Candidate of Immunostimulatory Potential in Pulmonary Tuberculosis Infection: Analysis of Interleukin-12 and Interferon Gamma Cytokines

Etlingera rubroloba A.D. Poulsen (E. rubroloba) is traditionally utilized by several ethnic groups in Southeast Sulawesi to treat typhoid fever and enhance immunity. Scientifically, it has been shown to stimulate macrophage phagocytic activity in response to gram-positive bacterial infections. However, its immunostimulatory effects on Mycobacterium tuberculosis (Mtb) remain unexplored, warranting further investigation for potential tuberculosis (TB) applications. This study aims to evaluate the immunostimulatory activity of the ethanol extract of E. rubroloba fruit by assessing interleukin-12 (IL-12) and interferon-gamma (IFN-γ) levels in a murine model infected with Mtb. An experimental research design was implemented using 24 male mice, which were randomly assigned to six treatment groups: normal control (untreated), negative control (0.5% Na-CMC), positive control (commercial Phyllanthus extract), and three dosage groups of E. rubroloba extract (200, 300, and 400 mg/kg BW). Treatments were administered orally for seven consecutive days, followed by Mtb infection on day eight. IL-12 and IFN-γ levels were measured using the sandwich ELISA technique. The results showed the highest IL- 12 and IFN-γ levels in the 400 mg/kg BW extract group, reaching 12.151 ng/mL and 7.28 pg/mL, respectively, while the negative control group exhibited the lowest levels (5.808 ng/mL and 3.08 pg/mL). Statistical analysis with one-way ANOVA and Tukey’s post hoc test indicated that E. rubroloba extracts significantly increased IL- 12 and IFN-γ levels compared to controls (p<0.05), supporting its potential as an immunostimulatory agent. These findings suggest that E. rubroloba fruit extract may be further developed as a promising natural immunostimulant for TB management, providing a novel contribution to the scientific understanding of this species.