IL6 and pulmonary fibrosis: Similarly, B6.129S2-Il6tm1Kopf/J (IL-6 knockout) mice treated with anti-CD47 antibody and the PD-1 blocking reagent HAC similarly resolved their lung fibrosis confirming synergistic antifibrotic efficacy of IL-6 and immune-checkpoint inhibition (Fig. 6e and Supplementary Fig. 6c–e).