T cell motility in tissues is thought to be directed by chemokine gradients and integrin-dependent adhesive interactions within the stromal environment. In Science Immunology, Ruef et al. identify a new form of chemoattractant-independent immune surveillance by tissue-resident CD8⁺ T memory (T_RM) cells that reside in exocrine gland tissues. T_RM cells in exocrine glands expressed more F-actin and non-muscle myosin IIA (MYH9) and exhibited more actomyosin contractility than naive T cells or T_RM cells found in other tissues. These exocrine T_RM cells utilize environmental mechanosensing via nuclear deformation to trigger Ca²⁺-dependent phospholipase A₂ and arachidonic acid signaling to activate their actomyosin-dependent motility. Disruption of this nuclear deformation mechanosensing pathway in T_RM cells suppressed their ability to scan and detect target cells in exocrine tissues, which suggests that this form of immunosurveillance is unique for these tissues. How these exocrine tissues instruct infiltrating CD8⁺ T cells to adopt this scanning behavior remains to be determined.

组织中 T 细胞的运动被认为是由基质环境内的趋化因子梯度和整合素依赖性粘附相互作用引导的。在《科学免疫学》中，Ruef 等人。通过驻留在外分泌腺组织中的组织驻留 CD8 ⁺ T 记忆 (TRM ₎细胞，确定了一种新形式的不依赖于趋化剂的免疫监视。外分泌腺中的T _{RM细胞比其他组织中发现的初始 T 细胞或 T RM}细胞表达更多的 F-肌动蛋白和非肌肉肌球蛋白 IIA (MYH9)，并表现出更多的肌动球蛋白收缩性。这些外分泌 T _RM细胞通过核变形利用环境机械感应来触发 Ca ²⁺依赖性磷脂酶 A ₂和花生四烯酸信号传导，以激活其肌动球蛋白依赖性运动。_{T RM}细胞中这种核变形机械传感途径的破坏抑制了它们扫描和检测外分泌组织中靶细胞的能力，这表明这种形式的免疫监视对于这些组织来说是独特的。这些外分泌组织如何指示浸润的 CD8 ⁺ T 细胞采取这种扫描行为仍有待确定。