Hiromi Nagano1,2*, Issei Nagano1,2, Masaki Kawabata1,2, Junichiro Ohori1,2 and Yuichi Kurono1,2
1Department of Pediatric Dentistry, Immunobiology Vaccine Center, Institute of Oral Health Research University of Alabama at Birmingham, USA
2Department of Otolaryngology, Head and Neck Surgery, Kagoshima University Graduate School of Medical and Dental Sciences, Japan
Purpose: The purpose of the study was to investigate the efficacy of intranasolacrimal immunization for induction of Pneumococcal surface protein A (PspA)-specific Secretory IgA (S-IgA) Antibody (Ab) responses in the upper respiratory tract.
Methods: Mice intranasolacrimally immunized with PspA and Polyinosinic-polycytidylic acid (Poly(I:C)) four times at weekly intervals were compared with intranasolacrimal controls and intranasal immunization on the same schedule. One week after final immunization, Nasal Washes (NWs), saliva and plasma were evaluated with PspA-specific ELISA. Mice were challenged with S.
pneumoniae strain and CFUs in NWs was determined.
Results: Higher PspA-specific IgG (10.71 ± 1.60, P<0.01) and IgA (5.71 ± 1.25, P<0.01) Abs were present in plasma of vaccinated mice compared with controls (0.0 ± 0.0, 0.0 ± 0.0). Significantly increased PspA-specific S-IgA Ab responses were seen in NW (3.0 ± 1.0, P<0.01) and saliva (5.87 ± 1.46, P<0.01) of mice given intranasolacrimal PspA+Poly(I:C) compared with controls (0.0 ± 0.0, 0.0 ± 0.0). Importantly, mice given intranasolacrimal PspA+Poly(I:C) had significantly lower numbers of bacteria CFUs in NWs (2.43 ± 0.41, P<0.05) and NPs (3.57 ± 0.73, P<0.05) compared with controls (3.21 ± 0.47, 4.29 ± 0.58).
Conclusion: These results show that intranasolacrimal immunization induces antigen-specificmucosal and systemic immune responses same as intranasal immunization.
Intranasolacrimal immunization; Streptococcus pneumoniae; PspA; Poly(I:C)
Nagano H, Nagano I, Kawabata M, Ohori J, Kurono Y. Intranasolacrimal Immunization of Mice with Pneumococcal Surface Protein A Plus Poly(I:C) Protective Against Nasopharyngeal Carriage of Streptococcus pneumonia. Am J Otolaryngol Head Neck Surg. 2022;5(4): 1186..