IL4 and laryngotracheoesophageal cleft: Therefore, the preoperative ratio of the percentage of IFN-g-producing T cells (Th1) to IL-4-producing T cells (Th2) was significantly higher in healthy controls and patients who underwent LC than in those who underwent operations for malignancy, the means being 11.3 ± 4.3, 10.8 ± 5.6 and 6.8 ± 4.2 (p < 0.01), respectively.