ABSTRACT Oral vaccines that elicit a mucosal immune response may be effective against human immunodeficiency virus type 1 (HIV-1) because its transmission occurs mainly at the mucosa. The aim of this study was to construct recombinant Lactobacillus for oral delivery HIV-1 and evaluate their immunogenicity. A acidophilus strain expressing Gag on bacterial cell surface established by fusion with signal peptide anchor motif mucus binding protein (Mub) from L. or without coexpression Salmonella...

ABSTRACT Lactobacillus species are commensal bacteria that have long been recognized as probiotic microbes and generally regarded safe (GRAS) for human consumption. We investigated the use of L. gasseri a vaccine vector oral immunization against mucosal pathogens. Recent research has shown immune response to different lactobacilli can vary widely depending on or subspecies being studied. While some seem induce tolerance, others an adaptive response. This study characterized systemic...

ABSTRACT Display of heterologous antigens on the cell surface is considered a useful technique for vaccine delivery by recombinant lactobacilli. In this study, two Lactobacillus acidophilus derivatives displaying Salmonella flagellin (FliC) were constructed using different anchor motifs. one instance, FliC protein was fused to C-terminal region envelope proteinase (PrtP) and bound wall electrostatic bonds. other case, same antigen conjugated mucus binding (Mub) covalently associated with an...

Surface layer proteins of probiotic lactobacilli are theoretically efficient epitope-displaying scaffolds for oral vaccine delivery due to their high expression levels and surface localization. In this study, we constructed genetically modified Lactobacillus acidophilus strains expressing the membrane proximal external region (MPER) from human immunodeficiency virus type 1 (HIV-1) within context major S-layer protein, SlpA. Intragastric immunization mice with recombinants induced...

The potential role of probiotic bacteria as adjuvants in vaccine trials led to their use nonparenteral live mucosal vectors. Yet, interactions between these vectors, the host and microbiome are poorly understood. This study evaluates impact three probiotic, Lactobacillus acidophilus, vector strains, with host's immune response, on gut microbiome. One strain expressed membrane proximal external region from HIV-1 (MPER). other two MPER either secreted interleukin-1ß (IL-1ß) or surface...

Feline infectious peritonitis is a devastating, fatal disease of domestic cats caused by pathogenic mutant virus derived from the ubiquitous feline enteric coronavirus (FECV). Infection FECV generally subclinical, and little known about mucosal immune response that controls eliminates virus. We investigated against in an endemically infected breeding colony over seven-month period. Thirty-three were grouped according to seropositivity fecal shedding into naïve/immunologically quiescent,...

Safe and efficacious orally-delivered mucosal vaccine platforms are desperately needed to combat the plethora of mucosally transmitted pathogens. Lactobacillus spp. have emerged as attractive candidates meet this need known activate host innate immune response in a species- strain-specific manner. For selected bacterial isolates mutants, we investigated role key pathways required for induction subsequent adaptive responses. Co-culture murine macrophages with L. gasseri (strain NCK1785),...

The development of lactic acid bacteria as mucosal vaccine vectors requires the identification robust adjuvants to increase effectiveness. E. coli type I fimbriae adhesion protein FimH is interest a adjuvant it targets microfold (M) cells enhancing uptake into Peyer’s patches and can activate innate immune system via Toll-like receptor (TLR) 4 binding. Here, we displayed N-terminal domain on surface Lactobacillus acidophilus vector evaluated its ability L. responses. was robustly but did not...

Thymus involvement and the development of thymic lesions in HIV-1 infection is hypothesized to suppress thymus function limit T cell maturation replenishment peripheral lymphoid pool. Therapeutic modulation protect or enhance may therefore ameliorate lymphocytopenia retard disease progression. Thymotrophic agents, such as insulin-like growth factor type I (IGF-I), represent adjunctive but important methods treatment promote function. The assessment rhIGF-I lentiviral its impact on was...

In vitro data suggest that innate immune function in human immunodeficiency virus type 1-infected patients is compromised; however, vivo studies are lacking. Feline (FIV) infection cats provides an excellent model to explore vivo. The response against Listeria monocytogenes well understood, making it a useful probe.Recombinant L. carrying eukaryotic expression plasmids for feline tumor necrosis factor (TNF)- alpha , interleukin (IL)-10, interferon (IFN)- gamma and IL-15 were created...

Abstract The potential role of probiotic bacteria as adjuvants in vaccine trials led to their use nonparenteral live mucosal vectors. Yet, interactions between these vectors, the host and microbiome are poorly understood. This study evaluates impact three probiotic, Lactobacillus acidophilus , vector strains, with host’s immune response, on gut microbiome. One strain expressed membrane proximal external region from HIV-1 (MPER). other two MPER either secreted interleukin-1β (IL-1β) or...

Feline infectious peritonitis (FIP) is a systemic disease manifestation of feline coronavirus (FCoV) and the most important cause disease-related deaths in domestic cats. FIP has variable clinical but often characterized by widespread vasculitis with visceral involvement and/or neurological that typically fatal absence antiviral therapy. Using an aptamer-based proteomics assay, we analyzed plasma protein profiles cats who were naturally infected (n = 19) comparison to clinically healthy...

Regulatory T cells (Treg) are key players in the maintenance of peripheral tolerance, preventing autoimmune diseases and restraining chronic inflammatory diseases. Evidence suggests Treg NK have important roles feline immunodeficiency virus (FIV) pathogenesis; however, vivo studies investigating interplay between these two cell populations lacking. We previously described innate immune defects FIV-infected cats characterized by cytokine deficits impaired natural killer (NK) (NKT) functions....

The enzyme-linked immunospot (ELISPOT) assay is a sensitive and relatively simple for detecting secreted cellular products such as cytokines has become an invaluable immunological tool. ELISPOT been used extensively in human murine research but only recently to assess the feline immune system. For researchers studying disease or using cat model of disease, quantification cytokine-producing cells by technique investigations immunopathogenesis vaccine efficacy. example, use interferon (IFN)-γ...

Background Transmission of HIV-1 across mucosal surfaces is the most prevalent mode viral infection. Therefore, a successful vaccine must induce broad anti-viral immunity at surface. In present study, we investigated immunogenicity novel Lactobacillus gasseri vector for use in oral delivery HIV antigens. L. was genetically engineered to express Salmonella spp. flagellin (L. gasseri-FliC) – agonist Toll-like receptor 5 (TLR5) and potent activator innate immune cells.