Figure 6.

Evaluation of bone marrow plasma cells and spleen antibody-secreting cells. Numbers of influenza-specific IgG (A) and IgA (B) plasma cells in the bone marrow and IgG ASCs in the spleen (C) were determined 3 months after a single vaccination. The cells were cultured in the presence of either 4 μg/mL purified inactivated A/California/04/09 virus or with 1 μg/ml LPS which is a polyclonal stimulator as a positive control. Sixteen hours later, the supernatants were transferred to ELISPOT plates coated with purified inactivated A/California/04/09 virus (4 μg/mL). ASC and plasma cell numbers of vaccinated mice were considered positive if the numbers of spots were higher than the sum of naive infected group spots plus 3 times the standard deviation [25]. Data represent the mean ± standard error of the mean (SEM).