Water bath sonicator

All peptide formulations indicated in Table 1 (except OVA-SA peptide) were
prepared as
follows. One milligram of the peptide was hydrated with 40 μL
of 0.2 M NaOH solution, and subsequently, phosphate buffered saline
(PBS, 140 mM NaCl, 13 mM Na₂HPO₄, and 2.5 mM
NaH₂PO₄, pH 7.4) was added in 200 μL portions
up to 1 mL. After each step, the peptide dispersion was sonicated
in a water bath sonicator (Fisher Scientific, Loughborough, UK) for
3 min at 30 °C. Before reaching to final volume, the pH was adjusted
to pH 7.4 by dropwise adding 0.2 M HCl. To prepare the OVA-SA peptide
formulation, one milligram of this peptide was dissolved in 200 μL
of HFIP. After solvent evaporation, the obtained peptide film was
hydrated in 40 μL of 0.2 M NaOH, and then similar to other peptide
preparations, 1 mL of PBS (140 mM NaCl, 13 mM Na₂HPO₄, and 2.5 mM NaH₂PO₄, pH 7.4) was added
in 200 μL portions. After pH adjustment, some of the peptide
formulations were supplemented with CpG (20 μg per injection;
10 μL of a 2 mg/mL of a stock solution of CpG in PBS) as an
adjuvant (Table 2).