Bsc 1 cells

For assays where cells were infected before being used to immunize mice, 293A cells (ATCC, CRL-1573) were used. For in vitro viral growth or plaque assays, BSC-1 cells (ATCC, CCL26) were used. For antigen presentation assays; MutuDCs (originally a gift from Hans Acha-Orbea, Lausanne, Switzerland) (56 (link)), 293A cells, and 293KbC2 cells (57 (link)) were used. Unmodified WR was originally a gift from B. Moss (National Institutes of Health, Bethesda, MD). HSV-1 strain KOS was provided by F. Carbone (University of Melbourne, Melbourne, Australia). Both were grown and titrated according to standard methods. Where indicated, virus or virus-infected cells were diluted in PBS and heat inactivated by incubation at 60°C for 1 h. Alternative inactivation methods included treatment of concentrated stocks with H₂O₂ as published (8 (link)) and with 1% paraformaldehyde for 20 min.

HEK293T cells (ATCC, CRL-3216) and BSC-1 cells (ATCC, 3168) were cultured at 37°C in Dulbecco's Modified Eagle medium (DMEM) with 10% fetal bovine serum (FBS). Initial stock of VACV Western Reserve was obtained from Dr. Luis Sigal (Thomas Jefferson University). Specific-pathogen-free (SPF) 6-8-week-old female mice BALB/c and C57BL/6 were purchased from Beijing Vital River Animal Technology Co., Ltd (licensed by Charles River). Body weight of each mouse ranged from 18 g to 20 g. We used a “Completely Randomised” method to randomly allocate mice into intervention or placebo groups [11 (link)]. For example, there were 18 mice that needed to be randomly allocated into three treatments (A, B, and C) with a sample size of six. Briefly, the mice were first numbered from 1 to 18 using ear tags. Six “A”s, six “B”s and six “C”s were entered into column one and 18 random numbers were put in column two using the command “ = rand()”, and pulling down on the small box on the lower right of the cell. Columns one and two were then marked and sorted on column two using “data, sort”. The row numbers represent individual mice identification numbers. All mice used in this study were housed and bred in temperature-, humidity- and light- cycle-controlled SPF mouse facilities in IMCAS (20 ± 2°C; 50 ± 10%; light, 7:00–19:00; dark, 19:00–7:00).

HEK293T cells (ATCC, CRL-3216) and BSC-1 cells (ATCC, 3168) were cultured at 37°C in Dulbecco's Modified Eagle medium (DMEM) with 10% fetal bovine serum (FBS). Initial stock of VACV Western Reserve was obtained from Dr. Luis Sigal (Thomas Jefferson University). Specific-pathogen-free (SPF) 6-8-week-old female mice BALB/c and C57BL/6 were purchased from Beijing Vital River Animal Technology Co., Ltd (licensed by Charles River). Body weight of each mouse ranged from 18 g to 20 g. We used a “Completely Randomised” method to randomly allocate mice into intervention or placebo groups [11 (link)]. For example, there were 18 mice that needed to be randomly allocated into three treatments (A, B, and C) with a sample size of six. Briefly, the mice were first numbered from 1 to 18 using ear tags. Six “A”s, six “B”s and six “C”s were entered into column one and 18 random numbers were put in column two using the command “ = rand()”, and pulling down on the small box on the lower right of the cell. Columns one and two were then marked and sorted on column two using “data, sort”. The row numbers represent individual mice identification numbers. All mice used in this study were housed and bred in temperature-, humidity- and light- cycle-controlled SPF mouse facilities in IMCAS (20 ± 2°C; 50 ± 10%; light, 7:00–19:00; dark, 19:00–7:00).