CD4 and lymphedema: In a mouse model of tail lymphedema, CD4+ T-cell knockout mice were protected from chronic lymphedema.46 In a subsequent paper, the same group identified the proinflammatory cytokine interleukin-6 as a key regulator of adipose deposition in the setting of lymphedema.47 Garcia Nores et al showed that lymphatic injury leads to CD4+ T-cell activation in regional lymph nodes, and that these T cells migrate to the site of the initial injury.48 One might then assume that lymphatic damage creates a pathologic cycle in which migrating CD4+ T cells worsen the original lymphatic insult.