Moreover, evidence has shown that the levels of IL-4 and IL-5 and the frequency of Th2 (IL-5) were significantly higher in patients with SSc with lung fibrosis (SScFib+) than in patients with SSc without lung fibrosis (SScFib+), while the ratio of Th1/Th2 in bronchoalveolar lavage (BLA) samples was significantly lower in patients with SScFib+ than in those with SScFib− [30]. The gene discussed is IL4; the disease is systemic sclerosis.