Lentiviral Transduction of Mouse MSCs

The lentiviral vector was prepared as described previously.^{23 ,24 (link)} The NF-κB sensing and IL-4 secreting pCDH-NFKBRE-mIL4-copGFP vector^{12 (link)} or the control pCDH-CMV-MCS-copGFP vector (System Biosciences, Palo Alto, CA), pMD2G VSV-G envelope vector, and psPAX2 packaging vector were cotransfected to human embryonic kidney 293T cells (ATCC, Manassas, VA) using the calcium phosphate transfection kit (Clontech, Mountain View, CA) and 25 μM chloroquine. After dilution in the MSC culture medium supplied with 6 μg/mL of Polybrene (Sigma-Aldrich, St. Louis, MO), the virus was infected into mouse MSCs at multiplicity of infection (MOI) of 40. The infectious efficiency of this method was previously confirmed.^{23 ,24 (link)}