CD31 expression of CD4+ T cells was significantly decreased in patients with HBV-LC and those with HBV-PLC compared with CHB patients (both P<0.05, Fig 3), while no significant difference was observed between the patients with HBV-LC and those with HBV-PLC (P>0.05). The gene discussed is CD4; the disease is laryngotracheoesophageal cleft.