CD4 and lymphedema: Studies by the group of B. J. Mehrara and M. Detmar showed in clinical and experimental lymphedema that the majority of the cells that accumulate chronically in lymphedematous tissues are CD4+ T cells and that they contribute to the pathological changes including fibrosis (Avraham et al., 2010, 2013; Zampell et al., 2012c; Savetsky et al., 2014; Gousopoulos et al., 2016b).