On the other hand, our systematic review suggests the existence of a distinct specific immune cellular signature, namely elevated proinflammatory CD14+ CD16+ monocytes [61], reduction in cytotoxic CD8+ lymphocytes and IL-2-producing T cells [46], and of central memory CD8+, CD4+ T lymphocytes [63] has been shown in CRPS. This evidence concerns the gene CD4 and complex regional pain syndrome.