Tolylsulfonyl phenylalanyl chloromethyl ketone tpck treated trypsin

Madin-Darby canine kidney (MDCK) cells were cultured in Eagle's minimum essential medium (MEM) (Invitrogen, California, USA). Media were supplemented with 10% fetal bovine serum (FBS) (Invitrogen, California, USA), except the assays of influenza virus. Infections with human influenza A H3N2 virus (A/HongKong/CUHK-22910/2004) were carried out in serum-free medium formulated with 1 μg/mL of trypsin treated with tolylsulfonyl phenylalanyl chloromethyl ketone (TPCK-treated trypsin) (Sigma-Aldrich, Munich, Germany).

GLY was purchased from Yunnan Labreal Biotechnology Co. Ltd. from Kunming, Yunnan Province, China. The leaves were identified and kept at Li Dak Sum Yip Yio Chin R & D Centre for Chinese Medicine. Minimum essential medium (MEM) and fetal bovine serum (FBS) were purchased from Life Technologies (Gibco, New York, NY, USA). Tolylsulfonyl phenylalanyl chloromethyl ketone (TPCK)-treated trypsin and 4-Methylumbelliferyl-N-acetyl-α-D-neuraminic acid (MUNANA) were purchased from Sigma-Aldrich (St. Louis, MO, USA). The ELISA kit was purchased from BlueGene (Shanghai, China). Thin layer chromatography (TLC) plate, silica gel 60 RP-18 sheets and silica gel 60 sheets were purchased from Merck (Darmstadt, Germany), and a polyamine-6 plate was purchased from Sinopharm (Beijing, China). The stationary phase of column chromatography silica gel was purchased from Qingdao Marine Chemical Inc. (Qingdao, China), silica gel RP-18 was purchased from Merck (Darmstadt, Germany), MCI gel was purchased from Sigma-Aldrich (St. Louis, MO, USA), and Sephadex LH-20 was purchased from GE Healthcare (New York, NY, USA).

Rhei Radix et Rhizoma, Bombyx Batryticatus, Cicadae Periostracum and Curcumae Longae Rhizoma were purchased from Zisun Chinese Pharmaceutical Co., Ltd. (Guangzhou, China). Standard compounds of rhein, chrysophanol, emodin, aloe emodin and curcumin were purchased from Chengdu Pufeide Biotechnology Co., Ltd. (Chengdu, China). Oseltamivir was purchased from Yichang Changjiang Pharcaceutical Co., Ltd. (Wuhan, China). Minimum essential medium (MEM), Dulbecco’s modified eagle medium (DMEM) and fetal bovine serum (FBS) were purchased from Life Technologies (Gibco, NY, USA). Neuraminidase inhibitors screen kit (no. P0309) was purchased from Beyotime Institute of Biotechnology Co., Ltd. (Shanghai, China). Chicken erythrocytes were purchased from Lampire Biological Laboratories (PA, USA). Tolylsulfonyl phenylalanyl chloromethyl ketone (TPCK) treated-trypsin was purchased from Sigma-Aldrich (St. Louis, MO, USA). Mouse TNF-α, IFN-α and IL-2 Enzyme-linked immunosorbent assay (Elisa) kit were purchased from Invitrogen (Carlsbad, CA, USA). Water used in this study was purified by a Milli-Q system (Millipore, MA, USA). All culture plates were obtained from Greiner (Cellstar, Germany).