Jalalvand et al. (2014). Vaccine. doi: 10.1016/j.vaccine.2014.02.082
…of rabbit anti-PF Abs. Briefly, differentiation of HL60 cells into granulocytes was induced by suspending cells into culture medium containing 1.25% dimethyl sulfoxide for 5 days. Baby rabbit complement (Pel-freez Biologi- cals Rogers, AR) was used as a standardized source of complement. Bacteria were pre-incubated with various titers of affinity-purified Abs for 30 min at RT on a mini-orbital shaker. Subsequently,…
Pel-Freez products cited: Baby Rabbit Complement (31061)
Abstract
Nontypeable Haemophilus influenzae (NTHi) is one of the main aetiologies of childhood bacterial infections as well as exacerbations in COPD patients. Currently, no licensed NTHi vaccine exists. In the present study, we evaluated the potential of the conserved and ubiquitous surface protein Haemophilus Protein F (PF) as a vaccine candidate. Our results show that incubation of NTHi with anti-PF antibodies significantly increased the opsonophygocytosis of human promyelocytic leukemia cell line-derived granulocytes, leading to efficient killing of the bacteria (P≤0.05). The presence of anti-PF IgG titers in healthy adults (n=60) was investigated, and we found that 26% of healthy blood donors carried antibodies with the main antigenic epitope being PF(23-48). Finally, mice immunized with PF(23-48) attained a significantly increased capacity to clear NTHi as compared to a control group immunized with a peptide derived from Moraxella catarrhalis β-lactamase (P≤0.05). Taken together, our results indicate that PF is a potential NTHi-vaccine candidate.