Lymph node genesis is induced by signaling through the lymphotoxin β receptor

Abstract

We investigated lymphotoxin (LT) and TNF function in lymph node genesis and cellular organization by manipulating LTβ-R and TNF-R signaling. Lymph nodes developed in LTα(-/-) mice treated in utero with agonist anti-LTβ-R monoclonal antibody. Thus, LTβ-R signaling mediates lymph node genesis. Surprisingly, mucosal lymph nodes that can develop independently of LTα/LTβ-R interaction were generated. Normal mice treated in utero with LTβ-R-Ig and TNF-R55-Ig or anti-TNF lacked all lymph nodes, indicating that TNF signaling contributes to lymph node genesis. Lymph nodes generated in LTα(-/-) mice had disrupted cellular organization. Therefore, LTβ-R signaling during gestation is not sufficient to e..