600 mg/day was administered for 8 weeks.

A549 cells were seeded (2 x 10^5 cells/well) in 24-well plates and cultured with MEM supplemented with 10% FBS at 37 C under 5% CO2. For the pretreatment of the compounds, the confluent monolayers were washed once with FBS-free MEM at 24 h prior to virus inoculation, and incubated in FBS-free MEM supplemented with the pantetheine (0, 0.4 or 2 mM). For virus inoculation, A549 cells are infected with IAV at a multiplicity of infection (MOI) of 0.1 PFU/cell or mock-infected. One hr later, the virus inocula were removed, and infected cells were washed twice and then maintained in FBS-free MEM supplemented with trypsin (1.0 mkg/ml) and the pantetheine (0, 0.4 or 2 mM) at 34 C under 5% CO2. At designated hr post-inoculation (h.p.i.), culture supernatants were harvested for the plaque assay, and A549 cells were directly lysed with lysis buffer for RNA extraction and subjected to the measurement of viral and cellular mRNA. Five hundred mkl of IAV(1 x 10^5 PFU/100 ml) and an equal amount MEM containing 0, 0.4 or 2 mM of test substances (pantetheine, cysteamine, or pantothenic acid) were mixed and incubated for 30 min at 34 C, and then 100 mkl of the mixtures was subjected to the plaque assay.