Iscove s modified dmem imdm

293T and Burkitt's lymphoma cell lines (Raji, Daudi and Namalwa) were obtained from the Type Culture Collection of the Chinese Academy of Sciences (Shanghai, China); Ramos (Burkitt's lymphoma cell line) and Pfeiffer (DLBCL cell line) cell lines were purchased from the ATCC; and OCI-ly3 (DLBCL cell line) and OCI-ly6 (DLBCL cell line) cell lines were gifted by Dr. X. Jiang (China) and Professor T. Zhao (China), respectively. The 293T cell line was maintained in Dulbecco's modified Eagle's medium with 10% FBS (Gibco). Most lymphoma cell lines were maintained in Roswell Park Memorial Institute-1640 (RPMI-1640) with 10% FBS (Gibco), and the OCI-ly3 and the OCI-ly6 cell lines were maintained in ISCOVE's modified DMEM (IMDM) with 10% FBS (Gibco).

Dihydrofolatereductase deficient CHO cells (dhfr⁻ cells, purchased from Culture Collection of Chinese Academy of Science, Shanghai) were maintained in 37°C with 5% CO₂ in ISCOVE's modified DMEM (IMDM) (Gibco) supplemented with 10% fetal bovine serum (Gibco), 2% HT mix (Sigma), and 100nM methotrexate (MTX) (Sigma). Mouse macrophage cells and bone marrow cells were separated from healthy C57BL/6 mice and similarly cultured in DMEM supplemented with 10% FBS. HTNV strain 76118 was kept in our lab, and all related experiments were performed in a biosafety level 2 (BSL-2) setting.