To generate the P.a infection model, we determine the suitable concentration of P.a. Different concentration groups of P.a were cultured with the BEAS-2B cell line (5 × 105 cells), where 5 μl P.a, 50 μl P.a, and 500 μl P.a corresponds to a multiplicity of infection (MOI) of one, 10, and 100. The gene discussed is OCA2; the disease is infection.