IL6 and tuberculosis: Concomitantly increased IL-6 and IL-10 serum concentrations in tuberculosis patients have been described,10 and Harling et al. demonstrated a correlation between IL-6 and IL-10 levels both spontaneously and after M. tuberculosis-specific stimulation.1 Similar to IL-6, IL-10 induces STAT3 phosphorylation and SOCS3 expression, but in contrast to IL-6, SOCS3 is not capable of inhibiting IL-10 receptor signaling.