"Echinacea : immune boosting or immuno-suppressing?"

Echinacea reportedly boosts the immune system by stimulating antigen-presenting cells, natural killer cells and dendritic cells, whilst enhancing neutrophil phagocytosis. However, Echinacea likely modulates immune functioning at multiple loci and its action immuno-suppressively upon the T-cell system may tilt a net effect against a backdrop of immuno-upping elsewhere.
Hui-Ming Chen

Dong, G. C., Chuang, P. H., Forrest, M. and Chen, H. M.* (2007) "Echinacea : immune boosting or immuno-suppressing?" PharmaChem, 14-15