Prof Iain McInnes reviews two papers this month, and discusses the increased risk of HZ infection with upadacitinib, as well as the role of the JAK-STAT pathway in SpA pathenogenesis. Keep-up to date with the latest in arthritis and cytokine signalling with Prof Iain McInnes. Everything discussed is available in a more detailed slide format in the publications section at cytokinesignalling.com.