In vitro immunomodulatory activity of various extracts of Maltese plants from the Asteraceae family

Abstract

Various extracts of ten plants from the Asteraceae family were studied for their effects of on human peripheral T-lymphocytes in vitro. Five solvent systems were used to extract constituents from these plants. Phytochemical identification of the most prevalent phytochemical classes was carried out, followed by screening for pharmacological activity using the Brine Shrimp Lethality test (BST). One BST-negative and five BST-positive extracts were tested on human lymphocytes. Marked effects were observed in treated lymphocytes with all six extracts. However only two extracts caused lymphocyte activation and pronounced blastogenesis similar to that of phytohaemagglutinin (PHA). The results obtained indicate that in particular the petroleum ether extract of Calendula arvensis is relatively non-toxic to peripheral lymphocytes suggesting its potential use as an immune booster.