Protoporphyrin 9 cobalt chloride copp

Madin-darby Bovine Kidney (MDBK) cells were maintained in Dulbecco’s modified Eagle’s medium (DMEM; Life Technologies Corporation, New York, CA, USA) supplemented with 10% fetal bovine serum (FBS) and 1% antibiotic-antimycotic (Life Technologies Corporation, New York, CA, USA) at 37 °C and 5% CO₂. BVDV strain Oregon C24V (CVCC no. AV69) was propagated on MDBK cells and stored at –70°C. Protoporphyrin IX cobalt chloride (CoPP), a classical inducer of HO-1 gene expression, was purchased from Sigma-Aldrich (St. Louis, MO, USA).

Marc-145 cells (an African green embryonic kidney epithelial cell line, ATCC) were cultured in Dulbecco’s modified Eagle’s medium (Invitrogen, USA) supplemented with 10% foetal bovine serum (FBS; GIBCO) at 37 °C in a humidified atmosphere containing 5% CO₂. Porcine alveolar macrophages (PAMs) were collected from lung lavages of 6-week-old Yorkshire pigs (free of PRRSV, PCV2, PRV), as previously described, and cultured in RPMI-1640 (GIBCO) containing 10% FBS at 37 °C. Three North American genotype 2 PRRSV strains were employed. The highly pathogenic PRRSV strain BB0907 (GenBank accession no. HQ315835.1), which is maintained in our laboratory, was used for all experiments and is represented by “PRRSV” in this article. The PRRSV strains S1 (GenBank accession no. DQ459471.1) and FJ1402 (GenBank accession no. KX169191.1) were also used but are specifically mentioned by name (S1, a classical strain; FJ1402, a NADC30-like strain).
Xanthohumol, purity > 99%, was used for in vitro experiments (Selleck Chemicals, Houston TX, USA). Protoporphyrin IX cobalt chloride (CoPP), an inducer of HMOX1 expression, was purchased from Sigma (St. Louis, MO, USA).