CD38 and peripheral arterial disease: Our study confirmed that the study group using the quadruple therapy of Daratumumab combined with PAD regimen had an overall response rate of 67.5%, and that of the control group was 45%, with a statistically significant difference (p=0.04); it also showed no obvious increase in the rate of adverse reactions (p=0.48); obviously higher levels of CD3+, CD4+ and CD4+/CD8+ than those in the control group after treatment (p=0.00); and lower positive expression rate of CD38 and the expression level of Notch one on the membrane of plasma cells than those in the control group (p=0.00).