Hmc 1

Human airway epithelial cell (A549) and human mast cell (HMC-1) were purchased from American Type Culture Collection (Manassas, VA, USA). A549 cells were cultured in RPMI-1640 and HMC-1 cells were cultured in Iscove’s modified Dulbecco’s medium (Gibco, Grand Island, NY, USA) supplemented with 10% heat-inactivated fetal bovine serum (FBS), 100 U/mL penicillin G sodium and 100 μg/mL of streptomycin sulfate (Gibco). The cells were maintained at 37oC in 5% CO₂ humidified atmosphere.

The HaCaT and HDF cell lines were purchased from the Korean Cell Line Bank (KCLB, Seoul, Korea). The human mast cell line (HMC-1) was purchased from Millipore (Carlsbad, CA, USA). HaCaT and HDF cells were cultured in Dulbecco’s Modified Eagle’s Medium (DMEM) supplemented with 10% heat-inactivated fetal bovine serum (FBS) at 37℃ in a humidified 5% CO₂ atmosphere. HMC-1 cells were maintained in Iscove’s Modified Dulbecco’s Medium (IMDM, Thermo Fisher Scientific Inc.) supplemented with 10% FBS, 1.2 mM α-thioglycerol (Sigma-Aldrich), 2 mM L-glutamine, penicillin (100 IU/ml), and streptomycin (50 µg/ml) in the same CO₂ incubator. The medium for mast cells was changed every 3~4 days. The co-culture medium was prepared using a DMEM:IMDM mixture ratio of 3:1 (Table 1). Upon reaching confluence, the cells were treated with 0.05% trypsin in 0.53 mM EDTA and incubated for 3 to 5 minutes at 37℃. The cells were conditioned for at least 6 hours in serum-free medium before experimentation.

RAW264.7 macrophage cells were purchased from ATCC (Manassas, VA, USA), and human mast cells (HMC-1) were obtained from Jeonju AgroBio-Materials Institute (Jeonju, Korea). The RAW264.7 and HMC-1 cells were grown in DMEM and IMDM culture media, respectively, and supplemented with 10% FBS, 100 units/ml of penicillin and 100 μg/ml of streptomycin (Invitrogen, Carlsbad, CA, USA) in an incubator (37°C, 5% CO₂).