We applied IL-4, IL-13, or IL-4/IL-13 to primary cultures of adult MG with and without IL-1β to demonstrate a putative signaling mechanism for MG alternative activation, and found that Ym1, arg-1 and CD206 were enhanced by IL-4 and IL-4/IL-13, but not by IL-13 alone. The gene discussed is ARG1; the disease is myasthenia gravis.