IL1B and primary myelofibrosis: Additionally, by comparing the cytokine gene expression profile of bone marrow cells using Nanostring technologies, Wong et al. showed that the RNA transcript of IL1B, along with other pro-inflammatory cytokines, was 1.5-fold higher in overt-PMF as compared to pre-PMF patients, suggesting the association of IL1B gene expression with bone marrow fibrosis [50].