Quantity of the antigens of Streptococcus mutans serotype e and Candida albicans and its correlation with the salivary flow rate in early childhood caries.

Background: Streptococcus mutans involved in caries pathogenesis is classified into four serotypes, namely serotypes c, e, f, and k. Candida albicans can be found in the plaque of children with early childhood caries (ECC). Aims: The aim of this study was to analyze the quantity of the antigens of S. mutans serotype e and C. albicans and its correlation with the salivary flow rate in ECC. Materials and Methods: The antigen quantities of caries plaque samples and caries-free were determined using an enzyme-linked immunoassay with 450-nm optical density. Results: There was a significant difference between the quantity of S. mutans serotype e and C. albicans antigens in each salivary flow rate category (P < 0.05). The relationship between the antigen quantity of S. mutans serotype e and C. albicans was r = 0.624 (P > 0.05) for caries plaque samples and r = 0.628 (P > 0.05) for caries-free samples. Conclusion: the antigen quantities of S. mutans serotype e and C. albicans and the salivary flow rate might correlate to the pathogenesis of ECC.

Expression of TNF, IL1B, and iNOS2 in the neural cell after induced by Porphyromonas gingivalis with and without coating antibody anti -Porphyromonas gingivalis.

Porphyromonas gingivalis has virulence factors such as gingipain and lipopolysaccharide, causing bacteremia to reach the brain and activate neuroinflammatory release cytokines. This study analyzed the effect of the co-culture of neuron cells with P. gingivalis coated with anti -P. gingivalis antibodies against cytokines produced by neuron cells. The gene expressions of the TNF, IL1B, NOS2 in neurons was evaluated using RT-qPCR. The results showed that P. gingivalis coated with anti -P. gingivalis antibody before co-culture with neuron cells could decrease the gene expression of TNF, IL1B, and NOS2 of neuron cells.

Experimental and Field Results Regarding Immunity Induced by a Recombinant Turkey Herpesvirus H5 Vector Vaccine Against H5N1 and Other H5 Highly Pathogenic Avian Influenza Virus Challenges.

Vaccination against H5N1 highly pathogenic avian influenza (AI) virus (HPAIV) is one of the possible complementary means available for affected countries to control AI when the disease has become, or with a high risk of becoming, endemic. Efficacy of the vaccination against AI relies essentially, but not exclusively, on the capacity of the vaccine to induce immunity against the targeted virus (which is prone to undergo antigenic variations), as well as its capacity to overcome interference with maternal immunity transmitted by immunized breeding hens to their progeny. This property of the vaccine is a prerequisite for its administration at the hatchery, which assures higher and more reliable vaccine coverage of the populations than vaccination at the farm. A recombinant vector vaccine (Vectormune® AI), based on turkey herpesvirus expressing the hemagglutinin gene of an H5N1 HPAIV as an insert, has been used in several experiments conducted in different research laboratories, as well as in controlled field trials. The results have demonstrated a high degree of homologous and cross protection against different genetic clades of the H5N1 HPAIV. Furthermore, vaccine-induced immunity was not impaired by the presence of passive immunity, but on the contrary, cumulated with it for improved early protection. The demonstrated levels of protection against the different challenge viruses exhibited variations in terms of postchallenge mortality, as well as challenge virus shedding. The data presented here highlight the advantages of this vaccine as a useful and reliable tool to complement biosecurity and sanitary policies for better controlling the disease due to HPAIV of H5 subtypes, when the vaccination is applied as a control measure.

Effect of topical anti-Streptococcus mutans IgY gel on quantity of S. mutans on rats' tooth surface.

This study aims to evaluate the effect of anti-Streptococcus mutans IgY gel on quantity of S. mutans on rats' tooth surface. Sprague Dawley rats were exposed intra-orally with S. mutans Xc and were fed a caries-inducing diet 2000. The 24 rats were divided into four groups: group A had their teeth coated with IgY gel; group B received sterilized water as a control; group C had their teeth coated with IgY gel starting on the 29(th) day; and group D had their teeth coated with a gel without IgY. Plaque samples were swabbed from the anterior teeth for S. mutans colony quantification, and saliva was collected to measure immunoreactivity by enzyme-linked immunosorbent assay. The results indicated that the quantity of S. mutans in rats treated with IgY gel showed significant difference compared with the controls. After coating with IgY anti-S. mutans gel, the mean immunoreactivity in rat saliva was higher than that of the no treatment group. In conclusion, topical application with anti-S. mutans IgY gel reduced the quantity of S. mutans on the tooth surface.

Effects of soybean milk, chitosan, and anti-Streptococcus mutans IgY in malnourished rats' dental biofilm and the IgY persistency in saliva.

OBJECTIVE: This study aims to evaluate the eff ect of soybean milk containing a combination of anti-Streptococcus mutans IgY and chitosan to the colonization of S. mutans in the saliva and to the IgY persistency in the saliva. MATERIALS AND METHODS: Experimental malnourished Sprague-Dawley rats were fed with soybean milk that is enriched with anti-S. mutans IgY and chitosan. After 15 days of feeding, we evaluated the S. mutans in dental biofilm, in addition to the persistency level of anti-S. mutans IgY. RESULTS: The rats that received soybean milk supplemented with anti-S. mutans IgY had the lowest number of S. mutans colonies (p < 0.05). Anti-S. mutans IgY was detected in saliva after 15 days of feeding. CONCLUSIONS: Soybean milk supplemented with anti-S. mutans IgY and chitosan could signifi cantly reduce S. mutans biofilm, and the supplemented anti-S. mutans IgY persisted in these rats' saliva following the feeding period.

The large-scale production of an artificial influenza virus-like particle vaccine in silkworm pupae.

We successfully established a mass production system for an influenza virus-like particle (VLP) vaccine using a synthetic H5 hemagglutinin (HA) gene codon-optimized for the silkworm. A recombinant baculovirus containing the synthetic gene was inoculated into silkworm pupae. Four days after inoculation, the hemagglutination titer in homogenates from infected pupae reached a mean value of 0.8 million hemagglutination units (HAU), approximately 2,000 µg HA protein per pupa, more than 50-fold higher than that produced with an embryonated chicken egg. VLPs ranging from 30 nm to 300 nm in diameter and covered with a large number of spikes were detected in the homogenates. The spikes were approximately 14 nm long, similar to an authentic influenza HA spike. Detailed electron micrographs indicated that the VLP spike density was similar to that of authentic influenza virus particles. The results clearly show that the expression of a single HA gene can efficiently produce VLPs in silkworm pupae. When chickens were immunized with the pupae homogenate, the hemagglutination inhibition titer in their sera reached values of 2,048-8,192 after approximately 1 month. This is the first report demonstrating that a large amount of VLP vaccine could be produced by single synthetic HA gene in silkworm pupae. Our system might be useful for future vaccine development against other viral diseases.

Efficacy of a recombinant HVT-H5 vaccine against challenge with two genetically divergent Indonesian HPAI H5N1 strains.

The swift evolution rate of avian influenza (AI) H5N1 virus demands constant efforts to update inactivated vaccines to match antigenically with the emerging new field virus strains. Recently, a recombinant turkey herpesvirus (rHVT)-AI vaccine, rHVT-H5, expressing the HA gene of a highly pathogenic avian influenza (HPAI) H5N1 clade 2.2 A/Swan/Hungary/499/ 2006 strain inserted into FC-126 strain of HVT vector, has been developed to combat current threats in poultry industry. Here, we present the results of two trials where rHVT-H5 was tested alone or in combination with inactivated H5N1 vaccines (the latter vaccines contained antigens produced by using a clade 2.1.3 HPAI H5N1 virus [A/Ck/WestJava-Nagrak/2007] in the first trial or mixture of antigen produced by strain A/Ck/WestJava-Nagrak/2007 and A/Ck/Banten-Tangerang/2010 [bivalent vaccine] for second trial) in broiler chickens (Gallus gallus domesticus) carrying maternally derived antibodies to H5N1 and then challenged with Indonesian HPAI H5N1 field isolates. The effectiveness of vaccination was evaluated on the basis of clinical protection (morbidity and mortality) and measurement of virus shedding after challenge. Immune response to vaccination was followed by serology. In the first experiment, chickens were vaccinated at the day of hatch with rHVT-H5 alone (Group 1) or combined with inactivated vaccine at day old (Group 2) or at 10 days of age (Group 3). The chickens along with nonvaccinated hatch-mates were challenged at 28 days of age with the HPAI H5N1 field isolate dade 2.1.3 A/Chicken/WestJava-Subang/29/2007. Eighty, 100%, and 80% clinical protection was recorded in Group 1, 2, and 3, respectively. A similar experiment was performed a second time, but the chicks in Group 3 received the inactivated vaccine earlier, at 7 days of age. Challenge was performed at 28 days of age using a different H5N1 isolate, clade 2.1.3 A/Ck/Purwakarta-Cilingga/142/10. Clinical protection achieved in the second trial was 95%, 75%, and 90% in Group 1, 2, and 3, respectively. Shedding of challenge virus was significantly lower in the vaccinated groups compared with controls in both experiments. Vaccinated birds developed hemagglutination inhibition antibody response to H5N1 by the time of challenge. These experiments confirmed that the rHVT-H5 vaccine applied alone or in combination with inactivated H5N1 vaccines could provide high level (> 80%) clinical protection against divergent HPAI H5N1 field isolates after single immunization by 4 wk of age and a significant reduction in the excretion of challenge virus.

Complementary monoclonal antibody-based dot ELISA for universal detection of H5 avian influenza virus.

BACKGROUND: Rapid diagnosis and surveillance for H5 subtype viruses are critical for the control of H5N1 infection. RESULTS: In this study, H5 Dot ELISA, a rapid test for the detection of avian H5N1 influenza virus, was developed with two complementary H5 monoclonal antibodies. HA sequencing of escape mutants followed by epitope mapping revealed that the two Mabs target the epitope component (189th amino acid) on the HA protein but are specific for different amino acids (189Lys or 189Arg). Gene alignment indicated that these two amino acids are the most frequent types on this position among all of the H5 AIV reported in GeneBank. These two H5 Mabs were used together in a dot ELISA to detect H5 viral antigen. The detection limit of the developed test for multiple clades of H5N1 viruses, including clades 0, 1, 2.1, 2.2, 2.3, 4, 7, and 8, was less than 0.5 hemagglutinin units. The specificity of the optimized dot ELISA was examined by using 100 H5 strains, including H5N1 HPAI strains from multiple clades, 36 non-H5N1 viruses, and 4 influenza B viruses. No cross-reactivity was observed for any of the non-H5N1 viruses tested. Among 200 random poultry samples, the test gave 100% positive results for all of the twelve RT-PCR-positive samples. CONCLUSIONS: Considering that the test is convenient for field use, this H5 Dot ELISA can be used for on-site detection of H5N1 infection in clinical or environmental specimens and facilitate the investigation of H5N1 influenza outbreaks and surveillance in poultry.

An inactivated H5N2 vaccine reduces transmission of highly pathogenic H5N1 avian influenza virus among native chickens.

Vaccination against H5N1 highly pathogenic avian influenza in endemically affected areas is a potentially attractive option for local prevention and control. In Indonesia the majority of local outbreaks have occurred in back yard flocks with native chickens, and it is therefore of interest to determine whether these birds can be protected against infection by vaccination. To this end two transmission experiments were carried out with H5N1 virus (A/chicken/Legok/2003) in vaccinated and unvaccinated native chickens. The vaccine contained an inactivated heterologous H5N2 strain (A/turkey/England/N28/73 H5N2). Birds were vaccinated at 4 and 7 weeks of age and challenged at 10 weeks of age. During 10 days post-challenge tracheal and cloacal swabs were taken for virus isolation, and serum blood was collected regularly to measure haemaglutinin inhibiting (HI) antibody responses. The results show that transmission of H5N1 virus was rapid and efficient in unvaccinated birds, that infection and transmission were completely prevented in vaccinated birds, and that vaccinated birds that were exposed to unvaccinated inoculated birds were still protected from infection. These findings indicate that vaccination with a heterologous H5N2 vaccine is able to prevent virus transmission in flocks of native chickens.