BACKGROUND: Previous studies have shown that PADMA-28, a multicomponent, traditional Tibetan herbal plant preparation possesses a variety of beneficial effects on several experimental models of inflammatory and immune processes, including autoimmune diabetes and autoimmune encephalomyelitis. In humans, PADMA-28 attenuated the symptoms associated with intermittent claudications in atherosclerotic patients.OBJECTIVE: To assess the effect of PADMA 28 on the immune system, e.g. cytokine (interleukins) production. DESIGN: Cytokine production by human blood monocytes (derived from 12 healthy donors) stimulated in vitro, either by endotoxin (LPS) from Salmonella typhi or by lipoteichoic acid (LTA) from group A Streptococci was modulated by PADMA-28. RESULTS: The present study showed that an aqueous extract of PADMA-28 strongly decreased the production of the inflammatory cytokines IL-1beta, IL-6, IL-8 and TNF-alpha, and more moderately, also decreased the anti-inflammatory cytokine IL-10 induced by LPS. However, the LTA - induced IL-10 production was [not significantly] increased by the low dose PADMA-28, while not effected at all by the higher dose of PADMA-28. CONCLUSIONS: The data from these finding suggest a possible clinical efficacy of PADMA-28 either in autoimmune and in inflammatory conditions or in post-inflammatory sequelae, as previously shown in in vivo and human studies, probably by decreasing inflammatory cytokines.