title: Condensed tannins from Botswanan forage plants are effective priming agents of γδ T cells in ruminants.
abstract: The potential impact of extracts from forage plants on γδ T cell activity in ruminants was evaluated using an in vitro immunoassay. This study investigated whether plant extracts could prime γδ T cells via up-regulation of CD25 (interleukin-2 receptor alpha). Purified Sephadex LH-20 fractions, isolated from Viscum rotundifolium, Viscum verrucosum, Tapinanthus oleifolius and Grewia flava, were screened against γδ T cells on kid, lamb and calf peripheral blood lymphocytes. Condensed tannins (CT) from G. flava significantly primed γδ T cells in kids up to 64.75% at 10 μg/mL, which was statistically significant relative to the negative control at 22.66% (p=0.004). CT from T. oleifolius also induced priming of γδ T cells in kids, while fractions from V. rotundifolium and V. verrucosum induced minimal priming of γδ T cells. In contrast, there was no significant priming of γδ T cells from lambs and calves for any of the tested fractions (p>0.05). These findings suggest that CT from a selected range of Botswanan forage plants can stimulate the immune system in vivo in selected ruminant species and may participate in enhancing host innate immune responses.
authors.affiliation: Botswana College of Agriculture, Private Bag 0027, Gaborone, Botswana. Olekile_Tibe@hotmail.com
authors.forename: O
authors.initials: O
authors.lastname: Tibe
authors.forename: A
authors.initials: A
authors.lastname: Pernthaner
authors.forename: I
authors.initials: I
authors.lastname: Sutherland
authors.forename: L
authors.initials: L
authors.lastname: Lesperance
authors.forename: D R K
authors.initials: DR
authors.lastname: Harding
mesh_terms: D000818:Animals; D001902:Botswana; D005434:Flow Cytometry; D053645:Interleukin-2 Receptor alpha Subunit / Q000276:immunology; D016018:Least-Squares Analysis; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000276:immunology; D008213:Lymphocyte Activation / Q000187:drug effects; D018515:Plant Leaves / Q000276:immunology; D010944:Plants / Q000187:drug effects / Q000276:immunology*; D044945:Proanthocyanidins / Q000494:pharmacology*; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000276:immunology*; D012418:Ruminants / Q000276:immunology*; D013601:T-Lymphocytes / Q000187:drug effects* / Q000276:immunology*
chemical_list: D053645:Interleukin-2 Receptor alpha Subunit; D044945:Proanthocyanidins; D016692:Receptors, Antigen, T-Cell, gamma-delta