Immunomodulatory effects of Umakhonya®: A South African commercial traditional immune booster

• We evaluated the cytotoxicity and immunomodulatory properties of a local commercially available traditional medicine using THP-1 monocytes.
• High concentrations of this product were significantly cytotoxicity.
• Lower non-cytotoxic doses increased chemokines secretion in normal THP-1 cells accompanied by increased NF-κβ activity at the lowest dose.
• LPS stimulated THP-1 cells did not show a significant change in chemokines secretion with no significant increase in NF-κβ activity.

South Africa is currently experiencing an increase in the number of traditional medicine preparations which purport to have immune boosting effects. This is largely related to the high prevalence of HIV infections. This study therefore aimed to evaluate the possible immunomodulatory mechanisms of uMakhonya®, one of the widely used commercial immune boosters, using THP-1 monocyte cells. Endotoxin-free doses of uMakhonya® ranging from 1000 μg/mL to 10 μg/mL were used to evaluate the cytotoxic effects, cell migration, secretion of twelve different chemokines and possible modulation of nuclear factor kappa Beta (NF-κβ) transcriptional activity. This commercial traditional medicine product was shown to induce dose dependent cytotoxicity with high doses significantly (p < 0.05) cytotoxic to monocytes (IC50 of 100.08 and 107.68 μg/mL for normal and LPS stimulated THP-1 cells respectively) when compared to untreated cells. The lower doses were shown to have no significant (p > 0.05) chemo-attractant effects in the cell migration assay. UMakhonya® at these lower and less cytotoxic doses induced a significant (p < 0.05) increase in secretion of chemokines in unstimulated THP-1 cells when compared to untreated and cyclosporine treated cells. In LPS-stimulated THP-1 cells only MIP-1β secretion was significantly increased by both 100 and 10 μg/mL. In both unstimulated and LPS-stimulated THP-1 cells the lowest dose of uMakhonya® increased transcriptional activity of NF-κβ which may explain the increase in chemokines secretion. Therefore this in vitro study showed that uMakhonya® is cytotoxic at high doses, did not show any chemo-attractant effects and induced significant increases in chemokines secretion. Increased transcriptional activity of NF-κβ in treated cells may contribute to increased chemokines secretion. This study on uMakhonya® should form the benchmark for the research of the high number of related products that are sold commercially in South Africa.