Granulocytes and plasmatocytes from <i>Euclea</i> and <i>Lithacodes</i> display phagocytic activity.

<p>(A) Hemocyte cells from <i>Euclea delphinii</i> and <i>Lithacodes fasciola</i> are capable of phagocytosing beads (a, b) and <i>E. coli</i> bacteria (c, d). Image overlays show hemocytes containing phagocytosed beads (green) in (a) <i>Euclea</i> and (b) <i>Lithacodes</i> as well as labeled <i>E. coli</i> (red) inside phagocytic cells in (c) <i>Euclea</i>, and (d) <i>Lithacodes</i>. Inset in (d) shows non-fluorescent extracellular bacteria. (B) Percentage of phagocytosis-positive cells for each hemocyte type, shown as mean ± SE. Phagocytosis-positive cells were counted from six different field views per animal (n = 4) for both species. Granulocytes (Gr) were significantly more efficient at engulfing bacteria compared to plasmatocytes (Pl) in both <i>Euclea</i> (t = 3.805, df = 6, <i>P</i> = 0.0089) and <i>Lithacodes</i> (t = 3.093, df = 6, <i>P</i> = 0.0213), whereas oenocytoids (Oe) are not phagocytic. ** = <i>P</i><0.01; * = <i>P</i><0.05; Scale bar = 25 µm.