Qing-an Xu

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Targeting antigens to antigen-presenting cells by fusion to cytotoxic T lymphocyte-associated antigen 4 (CTLA4) has been shown to be a highly efficient method to enhance the efficacy of DNA vaccines. The purpose of this study was to determine the immunogenicity and protective efficacy of the targeted fusion DNA construct pGJA-P, which contains the signal(More)
AIM To evaluate the comparative immunogenicity and protective efficacy of the cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) fusion anti-caries DNA vaccines pGJA-P/VAX1, pGJA-P, and non-fusion anti-caries DNA construct pGLUA-P in hamsters. In addition, the ability of CTLA-4 to target pGJA-P/VAX1-encoding antigen to dendritic cells was tested in vitro.(More)
The rationale of bacterial replacement therapy against dental caries is that relatively avirulent strains of Mutans Streptococi (MS) are most likely to occupy the same ecological niche in plaque as their more cariogenic counterparts. As known, lactate dehydrogenase (LDH) deficiency has been proposed as one aspect of a strategy to construct an effector(More)
AIM To investigate the effects of co-delivering IL-6 expressing plasmid pCI-IL-6 on the immunogenicity of the anti-caries DNA vaccine pCIA-P, which encodes the surface protein antigen PAc of Streptococcus mutans. METHODS Plasmid pCI-IL-6 was constructed by inserting the murine IL-6 gene into the pCI vector. Expression of IL-6 in vitro was assessed using(More)
AIM To investigate how co-delivery of the gene encoding C-C chemokine ligand-19 (CCL-19) affected the systemic immune responses to an anti-caries DNA vaccine pCIA-P in mice. METHODS Plasmid encoding CCL19-GFP fusion protein (pCCL19/GFP) was constructed by inserting murine ccl19 gene into GFP-expressing vector pAcGFP1-N1. Chemotactic effect of the fusion(More)
Vitamin D is known to be closely associated with periodontitis; however, its exact mechanisms remain to be clarified. The present study aimed to investigate the influence of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) on Porphyromonas gingivalis (Pg)-stimulated cytokine production and the involved signaling pathways in macrophages. The main observation was that(More)
AIM To construct a dendritic cell (DC)-targeted DNA vaccine against FimA of Porphyromonas gingivalis and evaluate the immunogenicity and protection in mice. MATERIALS AND METHODS A targeted DNA plasmid pCTLA4-FimA, which encodes the signal peptide and extracellular regions of mouse cytotoxic T lymphocyte-associated antigen 4 (CTLA4), the hinge and Fc(More)
Periodontitis are among the most frequent infectious diseases affecting children and adolescents. The primary etiology of periodontal diseases is the bacterial plaque. Studies have demonstrated the feasibility of inducing immune responses by DNA vaccines against Porphyromonas gingivalis, the major aetiological agent of chronic periodontitis, and the(More)
OBJECTIVE To construct a new fusion anti-caries DNA vaccine pGJGAC/VAX encoding antigens of both S. mutans and S. sobrinus so as to enhance the protective effect of DNA vaccine against S. sobrinus infection. METHODS The CAT fragment of S. sobrinus OMZ176 gtf-I was amplified by semi-nest PCR and then inserted into the plasmid pGJA-P/VAX to construct the(More)
AIM To investigate the effects of anti-caries DNA vaccine-induced salivary secretory immunoglobulin A (S-IgA) antibodies on Streptococcus mutans (S. mutans) adherence and biofilms formation in vitro. METHODS Adult female Wistar rats were intranasally immunized with the anti-caries DNA vaccine pGJA-P/VAX. Their saliva samples were collected at different(More)