Researchers analysed 100 blood samples from the Solve ME/CFS Biobank of patients and results included finding 3 clusters. The cluster of Interleukin-16 (IL-16), IL-7 and VEGF-A was both significantly downregulated and tightly correlated with each other. IL-16 is a pro-inflammatory cytokine and the reduction shown may indicate immunodeficiency. IL-7 is indispensable for the creation and survival of immune cells (T cells, B cells, NK cells). VEGF-A: stimulates new blood vessel and muscle growth.