biostudies-literatureKurz LSwiss National Science FoundationNCATS NIH HHSResearch Commission of the Kantonsspital St. GallenNIAID NIH HHSNHLBI NIH HHSAmerican Society of Transplantation and Cellular TherapyAmerican Society of HematologyNCI NIH HHSNIH HHSe20242300https://www.ebi.ac.uk/biostudies/studies/S-EPMC12651234biostudies-literatureUnknown223(2)The interaction of immune cells in the lymph node microenvironment depends on the infrastructure and molecular cues provided by fibroblastic reticular cells (FRCs). In addition, concentric layers of still poorly defined mural cells, including vascular smooth muscle cells (VSMCs), are involved in positioning and regulating immune cell interactions in different lymph node compartments. Using time-resolved single-cell transcriptomics, combined with cell fate mapping and high-resolution confocal microscopy, we found that lymph node FRCs and VSMCs share a proliferating, CCL19-expressing embryonic progenitor. Trajectory analysis identified lymphotoxin β receptor (LTβR)-dependent lineages that gave rise to FRCs underpinning the subcapsular sinus, T and B cell zones, and the medulla. LTβR-independThe Journal of experimental medicineA common progenitor gives rise to fibroblastic reticular cells and vascular smooth muscle cells in murine lymph nodes.PMC12651234T32 HL007439R01-AI09162719/07R01 AI091627212260KL2-TR001879KL2 TR001879R01-CA278976R01 CA278976182583T32-HL007439De Martin ABugar EStanossek YMeili SLutge MBrandstadter JDCheng HWOnder LLudewig BMaillard IKurz LfalseA common progenitor gives rise to fibroblastic reticular cells and vascular smooth muscle cells in murine lymph nodes.The interaction of immune cells in the lymph node microenvironment depends on the infrastructure and molecular cues provided by fibroblastic reticular cells (FRCs). In addition, concentric layers of still poorly defined mural cells, including vascular smooth muscle cells (VSMCs), are involved in positioning and regulating immune cell interactions in different lymph node compartments. Using time-resolved single-cell transcriptomics, combined with cell fate mapping and high-resolution confocal microscopy, we found that lymph node FRCs and VSMCs share a proliferating, CCL19-expressing embryonic progenitor. Trajectory analysis identified lymphotoxin β receptor (LTβR)-dependent lineages that gave rise to FRCs underpinning the subcapsular sinus, T and B cell zones, and the medulla. LTβR-independ2026-01-01T00:00:00Z2026 Feb2026-06-05T17:56:23.656Z2026-05-19T03:12:02.528ZS-EPMC126512344129595010.1084/jem.20242300