Lysophosphatidic acid receptors LPA4and LPA6differentially promote lymphocyte transmigration across high endothelial venules in lymph nodes

• DOI: 10.1093/intimm/dxv072
• Publication Date: 2015-12-30T01:44:36Z
• Authors: Erina Hata; Naoko Sasaki; Akira Takeda; Kazuo Tohya; Eiji Umemoto; Noriyuki Akahoshi; Satoshi Ishii; Kana Bando; Takaya Abe; Kuniyuki Kano; Junken Aoki; Haruko Hayasaka; Masayuki Miyasaka
• Keywords: High endothelial venules; Extravasation; Lymphocyte homing receptor; Autotaxin; Adoptive Cell Transfer

Naive lymphocytes continuously migrate from the blood into lymph nodes (LNs) via high endothelial venules (HEVs). To extravasate HEVs, undergo multiple adhesion steps, including tethering, rolling, firm and transmigration. We previously showed that autotaxin (ATX), an enzyme generates lysophosphatidic acid (LPA), is highly expressed in ATX/LPA axis plays important role lymphocyte transmigration across HEVs. However, detailed mechanism underlying this axis's involvement has remained ill-defined. Here, we show two LPA receptors, LPA4 LPA6, are selectively on HEV cells (ECs) a major HEVs mice. In absence of expression, accumulated heavily within EC layer, compared to wild-type (WT) This accumulation was also observed LPA6 but it less pronounced. Adoptive transfer experiments using WT revealed deficiency ECs specifically compromised process, whereas effect not significant. These results indicate signals evoked differentially regulate extravasation peripheral LNs.