利用樹突狀細胞（Dendritic cells）呈現腫瘤相關的抗原能夠有效地誘發對抗腫瘤的免疫力。當無法得知特定腫瘤抗原的情況下，利用整個腫瘤細胞作為抗原來刺激樹突狀細胞是一個值得研究的策略。本篇論文的研究目的是在小鼠的動物模式上建立攝護腺癌的樹突狀細胞腫瘤疫苗，並且評估以下三種刺激樹突狀細胞的策略：1. 以腫瘤細胞裂解物（Tumor lysates）刺激樹突狀細胞。2. 以放射線照射的腫瘤細胞刺激樹突狀細胞。3. 以放射線照射的腫瘤細胞加上細胞激素-3（Interleukin-3, IL-3）共同刺激樹突狀細胞。樹突狀細胞可經由骨髓細胞在GM-CSF和IL-4五至六天的培養下分化增生而得，LPS的加入則會刺激樹突狀細胞更進一步分化為成熟樹突狀細胞。這些在體外培養產生的骨髓樹突狀細胞具有典型的樹突狀型態、細胞表面特殊分子、吞噬能力以及刺激不同源T細胞增生的能力。在本篇研究中，以放射線照射的TRAMP C1細胞株為抗原刺激樹突狀細胞做為攝護腺癌腫瘤疫苗，在預防腫瘤產生以及減緩腫瘤生長上最為有效，而IL-3的存在並沒有進一步增強這樣的免疫力。以TRAMP C1 lysates刺激樹突狀細胞相較之下無法有效地誘發抗腫瘤的免疫力。從本篇的實驗結果認為，使用放射線照射的腫瘤細胞做為抗原，是發展攝護腺癌樹突狀細胞腫瘤疫苗很有效的方式。

Dendritic cells（DCs）pulsed with tumor-associated antigens can effectively induce anti-tumor immunity. Antigen loading of DC with whole tumor cell preparations is an attractive mean when defined tumor-associated antigens are not available. The goal of this study was to establish a DC-based vaccine model for prostate cancer in mice and to evaluate three antigen loading strategies: DCs pulsed with whole tumor lysates, DCs pulsed with irradiated tumor cells, and DCs pulsed with irradiated tumor cells in the presence of IL-3. Mouse bone marrow-derived dendritic cells（BM-DCs） were generated after 5-6 days culture with GM-CSF and IL-4. Further maturation of BM-DCs could be induced by LPS for 24 hours. In vitro generated BM-DCs displayed typical DC morphology, surface markers expression, phagocytosis capacity and allostimulatory ability of T cell proliferation. DCs pulsed with irradiated TRAMP C1 cells were most effective in preventing or delaying tumor growth on tumor challenge. The presence of IL-3 did not further enhance this protective immunity. DCs pulsed with TRAMP C1 lystates seemed to be less effective compared to irradiated TRAMP C1 cells. These data suggested DCs pulsed with irradiated tumor cells is the most promising strategy in developing DC-based tumor vaccine for prostate cancer.

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