title: A Probiotic Adjuvant Lactobacillus rhamnosus Enhances Specific Immune Responses after Ocular Mucosal Immunization with Chlamydial Polymorphic Membrane Protein C.
abstract: Recent advances in the development of chlamydia vaccines, using live-attenuated or ultraviolet light-inactivated chlamydia, are paving the way for new possibilities to oppose the societal challenges posed by chlamydia-related diseases, such as blinding trachoma. An effective subunit vaccine would mitigate the risks associated with the use of a whole-cell vaccine. Our rationale for the design of an efficient subunit vaccine against Chlamydia trachomatis (Ct) is based on the membrane proteins involved in the initial Ct-host cell contact and on the route of immunization that mimics the natural infection process (i.e., via the ocular mucosa). The first aim of our study was to characterize the specific conjunctival and vaginal immune responses following eye drop immunization in BALB/c mice, using the N-terminal portion of the Ct serovar E polymorphic membrane protein C (N-PmpC) as the subunit vaccine antigen. Second, we aimed to examine the adjuvant properties of the probiotic Lactobacillus rhamnosus (LB) when formulated with N-PmpC. N-PmpC applied alone stimulated the production of N-PmpC- and Ct serovar B-specific antibodies in serum, tears and vaginal washes, whereas the combination with LB significantly enhanced these responses. The N-PmpC/LB combination initiated a T cell response characterized by an elevated percentage of CD25+ T cells and CD8+ effector T cells, enhanced CD4+ T-helper 1 skewing, and increased regulatory T cell responses. Together, these results show that eye drop vaccination with combined use of N-PmpC and a live probiotic LB stimulates specific cellular and humoral immune responses, not only locally in the conjunctiva but also in the vaginal mucosa, which could be a promising approach in Ct vaccine development.
authors.affiliation: OCUVAC - Center of Ocular Inflammation and Infection, Laura Bassi Centres of Expertise, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria.
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Inic-Kanada
authors.affiliation: Department of Research and Development, Institute of Virology, Vaccines and Sera - TORLAK, Belgrade, Serbia.
authors.forename: Marijana
authors.initials: M
authors.lastname: Stojanovic
authors.affiliation: Department of Research and Development, Institute of Virology, Vaccines and Sera - TORLAK, Belgrade, Serbia.
authors.forename: Emilija
authors.initials: E
authors.lastname: Marinkovic
authors.affiliation: Institut für Funktionelle Genomforschung der Mikroorganismen, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, Gebäude 25.02.U1, 40225, Düsseldorf, Germany.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Becker
authors.affiliation: OCUVAC - Center of Ocular Inflammation and Infection, Laura Bassi Centres of Expertise, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Stein
authors.affiliation: Department of Research and Development, Institute of Virology, Vaccines and Sera - TORLAK, Belgrade, Serbia.
authors.forename: Ivana
authors.initials: I
authors.lastname: Lukic
authors.affiliation: Department of Research and Development, Institute of Virology, Vaccines and Sera - TORLAK, Belgrade, Serbia.
authors.forename: Radmila
authors.initials: R
authors.lastname: Djokic
authors.affiliation: OCUVAC - Center of Ocular Inflammation and Infection, Laura Bassi Centres of Expertise, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria.
authors.forename: Nadine
authors.initials: N
authors.lastname: Schuerer
authors.affiliation: Institut für Funktionelle Genomforschung der Mikroorganismen, Heinrich-Heine-Universität Düsseldorf, Universitätsstr. 1, Gebäude 25.02.U1, 40225, Düsseldorf, Germany.
authors.forename: Johannes H
authors.initials: JH
authors.lastname: Hegemann
authors.affiliation: OCUVAC - Center of Ocular Inflammation and Infection, Laura Bassi Centres of Expertise, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria.
authors.forename: Talin
authors.initials: T
authors.lastname: Barisani-Asenbauer
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000276:immunology*; D002692:Chlamydia trachomatis / Q000276:immunology*; D005260:Female; D052201:Lacticaseibacillus rhamnosus; D051379:Mice; D008807:Mice, Inbred BALB C; D009061:Mouth Mucosa / Q000276:immunology*; D019936:Probiotics
chemical_list: D001426:Bacterial Proteins