개 말초혈액 다형핵 백혈구(PMNs)의 탐식능력과 순간산소과소비력 (OBA) 에 대한 fucoidan의 효과를 검토하였다. Fucoidan 그 자체는 PMNs의 탐식능력과 OBA에 직접적인 효과를 보이지 않았다. 그러나 fucoidan으로 배양한 PBMCs의 배양상층액은 PMNs의 탐식능력과 OBA를 농도의존적으로 증가시켰다. 또한, TNF-${alpha}$에 의한 PMNs의 탐식능력과 OBA의 측정 결과도 fucoidan으로 배양한 PBMCs 배양상층액의 그것과 유사하였다. 이러한 탐식능력과 OBA의 활성은 anti-TNF-${alpha}$ pAb를 처리했을 때 억제되었다. PBMCs 배양 상층액 속의 TNF-${alpha}$의 양을 정량한 결과 대조군에 비해 증가되었으며, PBMCs의 TNF-${alpha}$ mRNA 발현 정도도 fucoidan을 첨가한 경우 증가되었다. 이상의 결과로부터, fucoidan은 개 말초혈액 PMNs의 탐식능력과 OBA에 대하여 면역자극 작용을 가지고 있으며, 이것은 fucoidan의 자극에 의해 PBMCs에서 생산되어 분비되는 가용성 물질인 TNF-${alpha}$에 의해 나타나는 것으로 사료되었다.
The objective of this study was to examine the effect of fucoidan on the phagocytic capapcity and oxidative burst activity (OBA) of canine peripheral blood polymorphonuclear cells (PMNs). The phagocytic capacity and OBA of PMNs were evaluated simultaneously by using a flow cytometer. Fucoidan itself did not cause any direct effect on the phagocytic capacity and OBA of PMNs. However, the phagocytic capacity and OBA of PMNs were enhanced by the culture supernatant from PBMCs treated with fucoidan. The phagocytic capacity and OBA of PMNs were also increased by treatment with recombinant canine (rc) tumor necrosis factor (TNF)-${alpha}$. The ability of the culture supernatant from fucoidan-treated PBMCs to stimulate the phagocytic capacity and OBA of PMNs was inhibited by addition of anti-rc TNF-${alpha}$ polyclonal antibody (PAb) prior to the culture. The amount of TNF-${alpha}$ in the culture supematant from PBMCs was shown to increase upon treatment of fucoidan as compared with that of vehicle-treated PBMCs culture supematant. The level of TNF-${alpha}$ mRNA expression in PBMCs was also up-regulated by the fucoidan treatment. These results suggest that fucoidan has an immunoenhancing effect on the phagocytic capacity and OBA of canine PMNs, which is mainly mediated by TNF-${alpha}$ released from fucoidan-stimulated PBMCs.
