Several DAMPs have been shown to act as critical determinants in PDT-induced immune responses, for example by elevating calreticulin exposure (CRT) to the cancer cell surface [10–12], via heat shock proteins (HSP70 and HSP90) exposure on cancer cells [13–15], or extracellular adenosine triphosphate (ATP) [16, 17]. Here, CALR is linked to cancer.