S.C. Johnson K.V. Ewart L.L. Brown N.W. Ross C. A. Ottinger 1999 <p>We investigated the effects of a calcium-dependent mannose-binding lectin isolated from the serum of Atlantic salmon on <i>Aeromonas</i><i>salmonicida</i> viability and the anti-<i>A</i>. <i>salmonicida</i> activity of Atlantic salmon macrophages. In the absence of other factors, binding of this lectin at concentrations of 0.8, 4.0 and 20.0 ng ml⁻¹ to virulent <i>A. salmonicida</i> failed to significantly reduce (<i>P</i>&gt;0.05) cell viability. However, binding of the lectin to <i>A. salmonicida</i> did result in significant (<i>P</i>≤0.05) dose-dependent increases in phagocytosis, and bactericidal activity. Significant increases (<i>P</i>≤0.05) were also observed in phagocyte respiratory burst activity within the lectin concentration range of 4.0–20.0 ng ml⁻¹ but the stimulation was not dose dependent at these lectin concentrations. At the lowest lectin concentration tested (0.32 ng ml⁻¹), a significant decrease (<i>P</i>≤0.05) in respiratory burst was observed. The structure and activity of this lectin are similar to that of mammalian mannose-binding lectins, which are known to play a pivotal role in innate immunity. The presence of this lectin may be an important defense mechanism against Gram-negative bacteria such as <i>A. </i><i>salmonicida.</i></p> application/pdf 10.1016/S0742-8413(99)00009-2 en Elsevier Enhancement of anti-<i>Aeromonas salmonicida</i> activity in Atlantic salmon (<i>Salmo salar</i>) macrophages by a mannose-binding lectin article