Enables cytokine activity. Predicted to be involved in several processes, including defense response to other organism; positive regulation of cytokine production; and positive regulation of signal transduction. Predicted to be located in extracellular region. Is expressed in ductus deferens; epididymis; ileum; and testis. Used to study atopic dermatitis; autoimmune hemolytic anemia; cryoglobulinemia; and membranoproliferative glomerulonephritis. Orthologous to human TSLP (thymic stromal lymphopoietin). [provided by Alliance of Genome Resources, Apr 2022]