Severe Fever with Thrombocytopenia Syndrome (SFTS) is a newly emerging tick-borne disease caused by the SFTS virus (SFTSV), which belongs to the phlebovirus in the Bunyaviridae family. SFTSV is enveloped with a tripartite ambisense RNA genome. The L segment encodes the viral RNA-dependent RNA polymerase, the M segment encodes the two glycoproteins, Gc and Gn, and the S segment encodes the nucleoprotein (NP) and the nonstructural protein (NSs). NP participates in ribonucleoprotein (RNP) packaging and commonly detected early after infection, suggesting that the N protein is possible to be used as a target antigen for early diagnosis of SFTSV infection. In this study, we analyzed a highly immunogenic multi-epitope using GnGc and NP genes from a consensus sequence of SFTSV strain isolated from infected patients in Korea. The selected genes are constructed to the expression vector plasmid pJHL65 and the recombinant plasmid vector was transformed into the Δasd Δlon ΔcpxR Salmonella Typhimurium attenuated strain JOL912 and the expression of these antigens was verified by immunoblotting assay. We observed the significant levels of systemic IgG and mucosal IgM responses against the JOL912-derived antigen in the immunized BALB/c mice. The level of CD3+CD4+, CD3+CD8+ T lymphocyte subpopulation and TNF-α were also highly regulated in splenic T cells re-stimulated in vitro with NP and Gn/Gc multi-epitope selected antigens. Therefore, immunized mice with NP and Gn/GC multi-epitope recombinant proteins of attenuated Salmonella delivery system elicited T cell-related immune response, inducing an effective immune response. In conclusion, the attenuated Salmonella expressing NP-GnGc multi-epitopes could be a novel vaccine candidate against the SFTS virus.

In this study, we examined the protective immunity of a combination of seven Brucella abortus recombinant proteins; superoxide dismutase (rSodC), riboflavin synthase subunit beta (rRibH), 50S ribosomal protein (50s rL7/L12), nucleoside diphosphate kinase (rNdk), malate dehydrogenase (rMDH), arginase (rRocF), and elongation factor (rTsf) cloned in a pMal vector system and expressed in DH5α. Mice groups were immunized thrice with a combined subunit vaccine (CSV-7) at 0, 2, and 5 weeks and subsequently challenged with B. abortus at 5 × 104 CFU at 6 weeks. At four weeks post-infection, the mice were sacrificed and the bacterial burden in their spleens was quantified. Results revealed bacterial log reductions of 0.63 and 0.34 in comparison to PBS and maltose-binding protein (MBP), respectively. Cytokine profiling revealed a marked increase in IFN-γ (interferon-gamma), MCP-1 (macrophage chemoattractant protein-1) and IL-6 (interleukin 6) cytokines at 5-weeks post-immunization. On the other hand, only TNF was heightened at 7-weeks post-immunization. In general, this cytokine profile is consistently reflective of a Th1 immune response, which is beneficial for host immunoresistance.

We investigated the effects of two Brucella proteins expressed in a pMAL expression system, RocF and EF-Ts, as subunit vaccines on immune modulation and protective efficacy using a mouse model. Mice vaccinated with MBP-RocF and MBP-EF-Ts displayed increased production of TNF, IFN-, MCP-1, IL-10 and IL-6, and TNF and MCP-1, respectively. Furthermore, mice vaccinated with MBP-EF-Ts showed decreased induction of IFN- and Th2-related cytokines, IL-10 and IL-6. Higher proportions of CD4+ and CD8+ T cells were observed in the blood of mice vaccinated with MBP-RocF than in the PBS-vaccinated group, although the increases were not significant. Furthermore, significantly reduced Brucella proliferation in the spleens of the MBP-RocF and MBP-EF-Ts groups were observed, but inflammation of these organs was not attenuated. Overall, these results indicate that RocF and EF-Ts could be potential subunit vaccine candidates against animal brucellosis.

The bacterial lipopolysaccharide (LPS) mainly contributes to the structural integrity, survival and protection barrier against harsh environments. Therefore, the early stages in LPS or lipid A biosynthesis are attractive targets in the identification and development of inhibitors which would be effective against infections caused by Gram-negative bacteria. The bacterial outer membrane proteins (OMPs) meanwhile function as maintenance for structure, adhesion to other cells and substances, as well as development of resistance to antimicrobials. The LPS and LPS-related molecules, and OMPs are important immunogenic components of several important pathogens including Brucella, which have been extensively used in immunological studies and in the diagnosis of diseases. Here we review the importance, structure, functions and immunogenic aspects of LPS and OMPs particularly of Brucella which can be targeted for the prevention and diagnosis of brucellosis.

ReαlITent aphthous stomatitis (RAS) appears to be one of the most common oral diseases. However, the defmitive etiology of RAS is not well established, though many etiologic faαors have been suggested and examined. The present study was petformed to investigate the association between HIA and Korean recurrent aphthous stomatitis pa디ents. πle proportions of class 1 and class II HIA types expressed in 49 Korean subjects affected by recurrent aphthous stomatitis (RAS) and in 50 healthy controls were deteffi1Í11ed by microlymphocytotoxicity test. 까le sig띠ficance of the data was analyzed by chi-square test and Fisher' s exact test. πle proportions of HIA-Cw1 and -DR9 antigens were significantly higher in RAS pa디ents (p(0.05), whereas those of HIA-DR4 and -DQ2 antigens were significantly lower (p(0.05). 까le odds ratio (OR) were 2.8 for HIA-Cw1 and 2.7 for -DR9. πle etiologic fractions (EF) were 0.262 and 0.193, respectively. The results s맹gest that, in Koreans, there Í$ a sig띠ficant relation between HIA antigens and RAS. Genetic faαors ， reflected in the HIA type, may play an in1portant role in the development of RAS.