Characterization of the effects of Butanol fraction from Echinacea purpurea on human dendritic cells using genomic and proteomic studies

Abstract

Echinacea spp. is widely and extensively used as a candidate medicinal herb or food supplement, claimed for stimulating immune function, in American and European countries. Dendritic cells (DC) are professional antigen-presentating cells (APC) and play an important role in innate as well as adaptive immunities. In this study, we analyzed the immune-associated cell surface proteins (CD markers) and the differential genomic or proteomic expression patterns of dendritic cells treated with or without Echinacea butanol fraction of shoot plus leaf tissues (EBF/S plus L). Experimental results of Affymetrix DNA microarray chip analyses showed that specific cytokine genes (eg., IL-8, IL-1 beta, IL-18), chemokine genes (including CXCL 2, CCL 5, CCL 2 etc.,) and an anti-oxidant superoxide dismutase (SOD) gene were up-regulated within 4 h post treatment with the EBF/S plus L. Bioinformatics analyses were carried out to evaluate these responsive genes for possible involvement in immune or cellular-signaling mechanisms. In parallel, proteomics studies showed that expression levels of approximately 15 proteins were affected in DC within 12h or 24 h post treatment with EBF/S plus L. MALDI-TOF mass spectrometry analyses were then used to identify specific protein sequences of the differentially expressed proteins. We obserbed that the SOD protein expresstion was up-regulated 12 hr post EBF/S plus L treatment. In addition specific phytocompounds purified from Echinacea purpurea medicinal herb, were systematically tested by using bioactivity-guided assays for possible application as candidate therapeutics or health care supplements.