Using manual count, patients with EoE before treatment showed a significant larger number of CD3 cells (58.87 ± 25.78 vs 30.57 ± 15.72; p = 0.004), CD8 (57.17 ± 26.78 vs 24.69 ± 11.98; p = 0.002), and CD117/c-kit (12.64 ±7.03 vs 5.61 ± 4.57; p = 0.005), compared with GERD patients. The gene discussed is CD8A; the disease is gastroesophageal reflux disease.