RNPC3 and pulmonary fibrosis: Different types of autoantibodies could be a marker for the different types of severity of lung fibrosis; anti-topoisomerase antibodies, anti-U11/U12 ribonucleoprotein (RNP) antibodies and anti-Th/To RNP antibodies are associated with an increased likelihood of developing clinically significant fibrosis (42, 43).