Lymphatic pumping and lymphatic transport of antigen to lymph node

淋巴管在维持液体平衡和促进免疫防御方面起着至关重要的作用。虽然心脏跳动来驱动血液循环，但淋巴的运输主要依靠淋巴管的泵送。淋巴泵是由淋巴管平滑肌细胞(SMC)收缩驱动的。淋巴泵的功能是推动淋巴和细胞运输到引流淋巴结(LN)。当抗原和树突状细胞通过传入淋巴管到达引流淋巴结(LN)时，它们必须离开血管并深入LN以激活T细胞反应。然而，淋巴流量的改变如何影响LN的抗原递送和抗原递呈尚不清楚。在我之前的研究中，我开发了一个活体成像模型来研究小鼠的淋巴泵。使用这个模型，我证明了一氧化氮(NO)是通过激活内皮源性一氧化氮合酶(ENOS)来维持生理状态下的淋巴泵送的。相反，诱导型一氧化氮合酶(INOS)负责在恶唑酮皮肤致敏诱导的炎症(OX-炎症)中抑制淋巴泵送。我们推测，NO调节淋巴泵，进而调节淋巴流速和流型，从而影响淋巴的抗原递送。

Lymphatic vessels play essential roles in maintaining fluid balance and facilitating immune defense. While the heart beats to drive blood circulation, lymph transport primarily relies on lymphatic vessel pumping. Lymphatic pumping is driven by lymphatic smooth muscle cell (SMC) contraction. The function of lymphatic pumping is to propel lymph and cells transport to the draining lymph node (LN). When antigen and dendritic cells reach the draining lymph node (LN) through afferent lymphatic vessels, they must exit the vessels and migrate deep into the LN to activate T cell responses. However, it is not clear how changes in lymph flow may affect antigen delivery and antigen presentation in LN. In my previous studies, I have developed an intravital imaging model to study lymphatic pumping in mice. Using this model, I demonstrated that nitric oxide (NO) is required to maintain lymphatic pumping in physiological condition via the activation of the endothelial-derived nitric oxide synthase (eNOS). In contrast, the inducible nitric oxide synthase (iNOS) is responsible for the inhibition of lymphatic pumping in oxazolone skin sensitization induced inflammation (OX-inflammation). We hypothesize that NO regulates lymphatic pumping, which consequently modulates lymph flow velocity and flow pattern, and affect antigen delivery in lymph node.