The authors thank Dr. G. Brennan, Queen’s University of Belfast, for his help in proof reading and language corrections. None of the authors has any conflicts of interest associated with this study. “
“Cry1Ac protoxin from Bacillus thuringiensis is a potent mucosal immunogen and adjuvant. When delivered BAY 80-6946 concentration intranasally (i.n.) Cry1Ac elicits significant antibody response and is able to improve vaccination against Naegleria
fowleri infection, but the functional effects occurring in nasal lymphocytes when this protein is administered alone have not been determined. Here, we investigated the effects of i.n. immunization with Cry1Ac on antibody production, lymphocyte activation and cytokine production in lymphocytes from nasal-associated lymphoid tissue (NALT) and nasal passages (NP). Our results show that i.n. immunization with Cry1Ac induced significant specific IgA and IgG cell responses, especially in NP. Besides, it increased the proportion of lymphocytes expressing the activation markers CD25 and CD69 in both nasal tissues, selleck chemical but differently. CD25 was increased in B cells along with CD4 and CD8 T cells from NALT and
NP, while CD69 was increased in B cells from both tissues but only in CD4 T cells from NP. Finally, we found that Cry1Ac augmented especially a Th2 profile of cytokines, as the proportion of T cells that spontaneously
produced IL-4, IL-5 and IL-10 was increased and this effect was higher in NP than in NALT. Fluorouracil mw These data contribute to explain the potent immunogenicity of Cry1Ac via i.n. route. The nasal mucosa is an important site for host defence against invading pathogens as it is the first site of contact with inhaled antigens [1]. In addition to its role in the defence of the upper and lower respiratory tracts, the nasal lymphoid system cooperates with the systemic immune system and affects immune reactions at distant mucosal sites, such as the urogenital tract and the gut [2, 3]. Consequently, new vaccination strategies based on nasal application have been designed and have proven to be effective procedures for the induction of antigen-specific immunity in respiratory and reproductive tissues [4]. There is much evidence to suggest that nasal-associated lymphoid tissue (NALT) may have an important role in the induction of mucosal immune responses after nasal immunization [5], while nasal passages (NP) and their associated lymphocytes are considered effector sites. However, only a few studies have systematically analysed the distinctive phenotypic and functional features existing in the lymphocyte populations residing at the different nasal compartments [5–8].