Development of a reverse genetics system to generate vaccine strain of Hepatitis A virus

Objective

Reverse genetic system have been used to generate mutant viruses to investigate the genetic features as well as to produce vaccine strain of various viruses. However, the virus producing system has not been applied to produce vaccine strain of Hepatitis A virus (HAV). Here, we established reverse genetic system to generate vaccine strain of HAV and assessed the generated HAV in terms of immunogenicity.

Methods

To produce HAV, MRC-5 cells were transfected with HAV RNA generated via in vitro transcription. To confirm the virus generation, we performed RT-PCR, Western blot, Rapid amplification of cDNA ends (RACE) and transmission electron microscopy (TEM) analysis using the supernatant of the HAV RNA transfected cells. To assess the immunogenicity of the generated HAV, mice were immunized with the generated and inactivated HAV and performed enzyme-linked immunosorbent assay (ELISA) to assess anti-HAV IgG using sera from the immunized mice.

Results

From the supernatant of HAV RNA transfected cells, HAV-specific RNA and protein were detected. TEM analysis showed that there are two types of HAV particles as shown in a previous report: naked and enveloped HAV, which is one of HAV features. Although seven nucleotide sequences are different in the coding sequence for structural protein compared to those of wildtype vaccine strain of HAV, genomic RNA analysis using RACE showed that the generated HAV have HAV-specific RNA as genome. In the immunogenicity study using mouse, the generated HAV induced HAV-specific IgG and the titer was comparable to wild-type vaccine strain of HAV.

Conclusions

We established the reverse genetic system to produce vaccine strain of HAV and confirmed that the generated HAV can be used as vaccine strain.

Identifying key gait features associated with the radiological grade of knee osteoarthritis

PURPOSE

Knee osteoarthritis (KOA) is characterized by pain and decreased gait function. This study assessed key features that can be used as mechanical biomarkers for KOA severity and progression. The identified features were validated statistically and were further examined by developing a classification model based on a machine-learning algorithm.

METHODS

The study included 227 volunteers with various grades of KOA. The severity of KOA was graded using the Kellgren-Lawrence (KL) system. A total of 165 features were extracted from the gait data. The key features were selected using neighborhood component analysis. The selected features were validated using the t-test. Then, the features were examined by building a classification model using a random forest algorithm.

RESULTS

Twenty features were identified that could discriminate the grade of KOA, including nine features extracted from the knee joint, seven from the hip, two from the ankle and two from the spatiotemporal gait parameters. The t-test showed that some features differed significantly between health and sever group, while some were significantly different among the severe group, and others were significantly different for all KL grades. The areas under the receiver operating characteristic curves for classification were 0.974, 0.992, 0.845, 0.894, and 0.905 for KL grades 0 through 4, respectively.

CONCLUSION

Key gait features reflecting the grade of KOA were identified. The results of the statistical analysis and machine-learning algorithm show that the features can discriminate the severity of disease according to the KL grade.

Intranasal immunization with pneumococcal surface protein A in the presence of nanoparticle forming polysorbitol transporter adjuvant induces protective immunity against the Streptococcus pneumoniae infection

Developing effective mucosal subunit vaccine for the Streptococcus pneumoniae has been unsuccessful mainly because of their poor immunogenicity with insufficient memory T and B cell responses. We thus address whether such limitation can be overcome by introducing effective adjuvants that can enhance immunity and show here that polysorbitol transporter (PST) serves as a mucosal adjuvant for a subunit vaccine against the Streptococcus pneumoniae. Pneumococcal surface protein A (PspA) with PST adjuvant induced protective immunity against S. pneumoniae challenge, especially long-term T and B cell immune responses. Moreover, we found that the PST preferentially induced T helper (Th) responses toward Th2 or T follicular helper (Tfh) cells and, importantly, that the responses were mediated through antigen-presenting cells via activating a peroxisome proliferator-activated receptor gamma (PPAR-γ) pathway. Thus, these data indicate that PST can be used as an effective and safe mucosal vaccine adjuvant against S. pneumoniae infection. STATE OF SIGNIFICANCE: In this study, we suggested the nanoparticle forming adjuvant, PST works as an effective adjuvant for the pneumococcal vaccine, PspA. The PspA subunit vaccine together with PST adjuvant efficiently induced protective immunity, even in the long-term memory responses, against Streptococcus pneumoniae lethal challenge. We found that PspA with PST adjuvant induced dendritic cell activation followed by follicular helper T cell responses through PPAR-γ pathway resulting long-term memory antibody-producing cells. Consequently, in this paper, we suggest the mechanism for safe nanoparticle forming subunit vaccine adjuvant against pneumococcal infection.

Sublingual Immunization With an RSV G Glycoprotein Fragment Primes IL-17-Mediated Immunopathology Upon Respiratory Syncytial Virus Infection

Respiratory syncytial virus (RSV) is the leading cause of serious respiratory tract disease but there is no licensed RSV vaccine. Immunopathological mechanisms have long been suspected as operating in the development of severe RSV disease and have hampered the development of safe and effective vaccines. Here, we show that unlike intranasal immunization, sublingual immunization with RSV glycoprotein fragment containing the central conserved region (Gcf) primes the host for severe disease upon RSV challenge. This increased pathology does not require replication by the challenge virus and is associated with massive infiltration of inflammatory cells, extensive cell death, and excessive mucus production in the airway and lungs. This exacerbated RSV disease primed by sublingual Gcf immunization is distinct from the immunopathology by G-expressing vaccinia virus or formalin-inactivated RSV, and preceded by prominent IL-17 production. IL-17 deficiency abolished the enhanced disease. Our results suggest a novel mechanism of RSV vaccine-induced immunopathology by IL-17, and highlights the importance of vaccination site.

Alveolar Macrophages Treated With Bacillus subtilis Spore Protect Mice Infected With Respiratory Syncytial Virus A2

Respiratory syncytial virus (RSV) is a major pathogen that infects lower respiratory tract and causes a common respiratory disease. Despite serious pathological consequences with this virus, effective treatments for controlling RSV infection remain unsolved, along with poor innate immune responses induced at the initial stage of RSV infection. Such a poor innate defense mechanism against RSV leads us to study the role of alveolar macrophage (AM) that is one of the primary innate immune cell types in the respiratory tract and may contribute to protective responses against RSV infection. As an effective strategy for enhancing anti-viral function of AM, this study suggests the intranasal administration of Bacillus subtilis spore which induces expansion of AM in the lung with activation and enhanced production of inflammatory cytokines along with several genes associated with M1 macrophage differentiation. Such effect by spore on AM was largely dependent on TLR-MyD88 signaling and, most importantly, resulted in a profound reduction of viral titers and pathological lung injury upon RSV infection. Taken together, our results suggest a protective role of AM in RSV infection and its functional modulation by B. subtilis spore, which may be a useful and potential therapeutic approach against RSV.

The recent ancestry of Middle East respiratory syndrome coronavirus in Korea has been shaped by recombination

Middle East respiratory syndrome coronavirus (MERS-CoV) causes severe cases of human respiratory disease. Since 2012, the victims have mainly come from the Middle East countries or sporadically from some other geographical regions seeded by the travelers who visited the Middle East. Such an introduction through travelling led to the emergence of a MERS-CoV outbreak in Korea in May 2015, which caused more than 140 confirmed human cases in less than a month. Using 70 complete genome sequences of MERS-CoV isolates, including the most recent sequences for the Korean and Chinese isolates, we reconstructed the phylogenetic relationships of the complete genome and the individual protein coding regions. The Korean MERS-CoV strain clustered in the previously established Hafr-Al-Batin-1_2013 clade together with two Saudi Arabian and one Chinese strain sampled in 2015. Although these four strains remained monophyletic in the entire protein-coding region, this clade showed different phylogenetic relationships across the genome, indicating a shared unique recombination pattern that is different from previously reported putative recombination strains. Our findings suggest that the recent ancestor of the Korean and its related MERS-CoV strains is characterized by unique mosaic genome pattern that is different from other putative recombinants.

Pandemic influenza virus, pH1N1, induces asthmatic symptoms via activation of innate lymphoid cells

BACKGROUND

The pandemic strain of the influenza A virus (pH1N1) in 2009 caused many complications in patients. In this study, we introduce asthmatic symptoms as a complication of pH1N1 infection in children, not having a relationship with asthma history. The aim of this study was to quantify asthmatic symptoms in pH1N1-infected children and elucidate the underlying mechanisms of airway hyper-responsiveness (AHR) induced in a murine model of pH1N1 infection.

METHODS

As a retrospective study, pH1N1-infected children who were hospitalized with moderate to severe acute asthmatic symptoms were enrolled and administered a methacholine challenge test (MCT) at 3 months post-discharge. Additionally, the induction of AHR by pH1N1 infection was measured by MCT in wild-type and Rag1(-/-) mice. The effect of the innate immune response on the development of AHR following pH1N1 infection was investigated.

RESULTS

More than 70% of the pH1N1-infected children without a pre-infection diagnosis of asthma had a negative response on the MCT. None of these children had recurrent wheezing or asthma during the 3 years following pH1N1 infection. The development of AHR in pH1N1-infected mice was associated with an elevation in IL-33 and innate lymphoid cells 2 (ILC2).

CONCLUSIONS

This study demonstrates that pH1N1 infection directly induces transient asthmatic symptoms in patients regardless of their medical history. pH1N1 infection was shown to stimulate the rapid development of AHR and Th2-type cytokine secretion in mice via the activation of ILC2; it may be activated independently of adaptive immunity.

Intranasal immunization with protective antigen of Bacillus anthracis induces a long-term immunological memory response

Although intranasal vaccination has been shown to be effective for the protection against inhalational anthrax, establishment of long-term immunity has yet to be achieved. Here, we investigated whether intranasal immunization with recombinant protective antigen (rPA) of Bacillus anthracis induces immunological memory responses in the mucosal and systemic compartments. Intranasal immunization with rPA plus cholera toxin (CT) sustained PA-specific antibody responses for 6 months in lung, nasal washes, and vaginal washes as well as serum. A significant induction of PA-specific memory B cells was observed in spleen, cervical lymph nodes (CLNs) and lung after booster immunization. Furthermore, intranasal immunization with rPA plus CT remarkably generated effector memory CD4(+) T cells in the lung. PA-specific CD4(+) T cells preferentially increased the expression of Th1- and Th17-type cytokines in lung, but not in spleen or CLNs. Collectively, the intranasal immunization with rPA plus CT promoted immunologic memory responses in the mucosal and systemic compartments, providing long-term immunity.

Immunogenicity of inactivated polio vaccine, given with or without mucosal adjuvants dmLT and TCTA1T in rat model (VAC9P.1102)

To eradicate polio, the use of oral polio vaccine (OPV) should be stopped to avoid circulation of vaccine-derived polioviruses (VDPVs). After OPV cessation, transition to inactivated polio vaccine (IPV) is recommended. This can only be accomplished when IPV induce better mucosal protection. This can be achieved by adding mucosal adjuvant to the IPV formulation. In the present study we used wistar rats to elucidate the adjuvant effect of double mutant heat-labile toxin (dmLT) of E. coli and recombinant cholera toxin (TCTA1T) on IPV. Rats were administered by intramuscular injection of 1.0-0.6-1.0 D-antigen units (DU) of Inactivated Polio type 1, 2 and 3 /rat. The E. coli dmLT and TCTA1T was used as adjuvant and was administered subcutaneously along with IPV. The control groups received IPV alone or PBS. Rats were immunized on days 0, 14 and 28 days. After last vaccination mice were sacrificed and spleen cells and blood were collected. IgA secreting cells specific for Polio Type1, 2 and 3 were measured by ELISPOT. Intramuscular immunization results in robust mucosal response in inactivated polio antigens + dmLT group compared to other groups. Further measurement of antibodies in serum doesn’t show significant difference among IPV and adjuvanted IPV groups. Thus the present data suggest that vaccination with IPV and dmLT results in specific induction of mucosal immunity, which will provide barrier to infection from oral fecal route.

Decontamination method using heat and relative humidity for radish seeds achieves a 7-log reduction of Escherichia coli O157:H7 without affecting product quality

We developed a novel decontamination method to inactivate Escherichia coli O157:H7 on radish seeds without adversely affecting seed germination or product quality. The use of heat (55, 60, and 65 °C) combined with relative humidity (RH; 25, 45, 65, 85, and 100%) for 24h was evaluated for effective microbial reduction and preservation of seed germination rates. A significant two-way interaction of heat and RH was observed for both microbial reduction and germination rate (P<0.0001). Increases in heat and RH were associated with corresponding reductions in E. coli O157:H7 and in germination rate (P<0.05). The order of lethality for the different treatments was generally as follows: no treatment <55 °C/25-65% RH ≒60 °C/25-45% RH ≒65 °C/25% RH <55 °C/85% RH =60 °C/65% RH <55 °C/100% RH =60 °C/85-100% RH =65 °C/45-100% RH. The most effective condition, 65 °C/45% RH, completely inactivated E. coli O157:H7 on the seeds (7.0 log CFU/g reduction) and had no significant effect on the germination rate (85.4%; P>0.05) or product quality. The method uses only heat and relative humidity without chemicals, and is thus applicable as a general decontamination procedure in spout producing plants where the use of growth chambers is the norm.

Effects of Defaunation on Fermentation Characteristics and Methane Production by Rumen Microbes In vitro When Incubated with Starchy Feed Sources

An in vitro experiment was conducted to examine the effects of defaunation (removal of protozoa) on ruminal fermentation characteristics, CH₄ production and degradation by rumen microbes when incubated with cereal grains (corn, wheat and rye). Sodium lauryl sulfate as a defaunation reagent was added into the culture solution at a concentration of 0.000375 g/ml, and incubated anaerobically for up to 12 h at 39°C. Following defaunation, live protozoa in the culture solution were rarely observed by microscopic examination. A difference in pH was found among grains regardless of defaunation at all incubation times (p<0.01 to 0.001). Defaunation significantly decreased pH at 12 h (p<0.05) when rumen fluid was incubated with grains. Ammonia-N concentration was increased by defaunation for all grains at 6 h (p<0.05) and 12 h (p<0.05) incubation times. Total VFA concentration was increased by defaunation at 6 h (p<0.05) and 12 h (p<0.01) for all grains. Meanwhile, defaunation decreased acetate and butyrate proportions at 6 h (p<0.05, p<0.01) and 12 h (p<0.01, p<0.001), but increased the propionate proportion at 3 h, 6 h and 12 h incubation (p<0.01 to 0.001) for all grains. Defaunation increased in vitro effective degradability of DM (p<0.05). Production of total gas and CO₂ was decreased by defaunation for all grains at 1 h (p<0.05, p<0.05) and then increased at 6 h (p<0.05, p<0.05) and 12 h (p<0.05, p<0.05). CH₄ production was higher from faunation than from defaunation at all incubation times (p<0.05).

Vaccinia-based influenza vaccine overcomes previously induced immunodominance hierarchy for heterosubtypic protection

Growing concerns about unpredictable influenza pandemics require a broadly protective vaccine against diverse influenza strains. One of the promising approaches was a T cell-based vaccine, but the narrow breadth of T-cell immunity due to the immunodominance hierarchy established by previous influenza infection and efficacy against only mild challenge condition are important hurdles to overcome. To model T-cell immunodominance hierarchy in humans in an experimental setting, influenza-primed C57BL/6 mice were chosen and boosted with a mixture of vaccinia recombinants, individually expressing consensus sequences from avian, swine, and human isolates of influenza internal proteins. As determined by IFN-γ ELISPOT and polyfunctional cytokine secretion, the vaccinia recombinants of influenza expanded the breadth of T-cell responses to include subdominant and even minor epitopes. Vaccine groups were successfully protected against 100 LD50 challenges with PR/8/34 and highly pathogenic avian influenza H5N1, which contained the identical dominant NP366 epitope. Interestingly, in challenge with pandemic A/Cal/04/2009 containing mutations in the dominant epitope, only the group vaccinated with rVV-NP + PA showed improved protection. Taken together, a vaccinia-based influenza vaccine expressing conserved internal proteins improved the breadth of influenza-specific T-cell immunity and provided heterosubtypic protection against immunologically close as well as distant influenza strains.

Development of safe and effective RSV vaccine by modified CD4 epitope in G protein core fragment (Gcf)

Respiratory syncytial virus (RSV) is a major cause of respiratory tract infection in infants and young children worldwide, but currently no safe and effective vaccine is available. The RSV G glycoprotein (RSVG), a major attachment protein, is an important target for the induction of protective immune responses during RSV infection. However, it has been thought that a CD4⁺ T cell epitope (a.a. 183–195) within RSVG is associated with pathogenic pulmonary eosinophilia. To develop safe and effective RSV vaccine using RSV G protein core fragment (Gcf), several Gcf variants resulting from modification to CD4⁺ T cell epitope were constructed. Mice were immunized with each variant Gcf, and the levels of RSV-specific serum IgG were measured. At day 4 post-challenge with RSV subtype A or B, lung viral titers and pulmonary eosinophilia were determined and changes in body weight were monitored. With wild type Gcf derived from RSV A2 (wtAGcf), although RSV A subtype-specific immune responses were induced, vaccine-enhanced disease characterized by excessive pulmonary eosinophil recruitment and body weight loss were evident, whereas wtGcf from RSV B1 (wtBGcf) induced RSV B subtype-specific immune responses without the signs of vaccine-enhanced disease. Mice immunized with Th-mGcf, a fusion protein consisting CD4⁺ T cell epitope from RSV F (F_51–66) conjugated to mGcf that contains alanine substitutions at a.a. position 185 and 188, showed higher levels of RSV-specific IgG response than mice immunized with mGcf. Both wtAGcf and Th-mGcf provided complete protection against RSV A2 and partial protection against RSV B. Importantly, mice immunized with Th-mGcf did not develop vaccine-enhanced disease following RSV challenge. Immunization of Th-mGcf provided protection against RSV infection without the symptom of vaccine-enhanced disease. Our study provides a novel strategy to develop a safe and effective mucosal RSV vaccine by manipulating the CD4⁺ T cell epitope within RSV G protein.

Mucosal vaccination with recombinant Lactobacillus casei-displayed CTA1-conjugated consensus matrix protein-2 (sM2) induces broad protection against divergent influenza subtypes in BALB/c mice

To develop a safe and effective mucosal vaccine against pathogenic influenza viruses, we constructed recombinant Lactobacillus casei strains that express conserved matrix protein 2 with (pgsA-CTA1-sM2/L. casei) or without (pgsA-sM2/L. casei) cholera toxin subunit A1 (CTA1) on the surface. The surface localization of the fusion protein was verified by cellular fractionation analyses, flow cytometry and immunofluorescence microscopy. Oral and nasal inoculations of recombinant L. casei into mice resulted in high levels of serum immunoglobulin G (IgG) and mucosal IgA. However, the conjugation of cholera toxin subunit A1 induced more potent mucosal, humoral and cell-mediated immune responses. In a challenge test with 10 MLD₅₀ of A/EM/Korea/W149/06(H5N1), A/Puerto Rico/8/34(H1N1), A/Aquatic bird /Korea/W81/2005(H5N2), A/Aquatic bird/Korea/W44/2005(H7N3), and A/Chicken/Korea/116/2004(H9N2) viruses, the recombinant pgsA-CTA1-sM2/L. casei provided better protection against lethal challenges than pgsA-sM2/L. casei, pgsA/L. casei and PBS in mice. These results indicate that mucosal immunization with recombinant L. casei expressing CTA1-conjugated sM2 protein on its surface is an effective means of eliciting protective immune responses against diverse influenza subtypes.

Gender-specific pleiotropic bone-muscle relationship in the elderly from a nationwide survey (KNHANES IV)

SUMMARY

The aim of this study was to examine the gender-specific association between sarcopenia and bone geometry/metabolic parameters. Low muscle mass was associated with greater deterioration of bone than in deterioration of glucose or lipid profiles. This bone-muscle relationship was more prominent in men than in women.

INTRODUCTION

There are few studies that report on gender differences in the effects of low muscle mass on bone and metabolic parameters in elderly subjects. This study aimed to assess the gender-specific influence of muscle mass on bone and metabolic parameters.

METHODS

A total of 2,264 participants (940 men and 1,324 women) whose age ranged from 65 to 92 years were analyzed using data from The Fourth Korea National Health and Nutrition Examination Surveys (2008-2009). We measured bone mineral density (BMD) and appendicular muscle mass using the dual-energy X-ray absorptiometry and also measured metabolic profiles.

RESULTS

The age-related trend in bone and muscle coincided in men but not in women. Femoral neck (FN) and total hip (TH) BMD were highly correlated with muscle mass in both genders. However, in women, this correlation was not significant in the lumbar spine (LS). In addition, this positive correlation was stronger in the FN or TH than in the LS and was stronger in men than in women. Subjects with sarcopenia were at a higher risk for osteoporosis in the FN, TH, and LS in men, and in the TH and FN in women. The degree of association between muscle mass and metabolic profiles was relatively very weak.

CONCLUSION

Bone-muscle relationship was more prominent in men than in women. The gender differences in bone-muscle relationship may be helpful for the development of gender-specific preventive strategies in the elderly, especially in men.

Evaluation of heterosubtypic cross-protection against highly pathogenic H5N1 by active infection with human seasonal influenza A virus or trivalent inactivated vaccine immunization in ferret models

The threat of highly pathogenic avian influenza (HPAI) H5N1 viruses to cause the next pandemic remains a major concern. Here, we evaluated the cross-protection induced by natural infection of human seasonal influenza strains or immunization with trivalent inactivated influenza vaccine (TIV) against HPAI H5N1 (A/Vietnam/1203/2004) virus in ferrets. Groups were treated with PBS (group A), infected with H1N1 (group B) or H3N2 (group C) virus, or immunized with TIV (group D). Twelve weeks after the last treatment, serological assays revealed that groups B and C, but not group D, sustained moderate immunogenicity against homologous viruses; cross-reactivity against the H5N1 virus was not detected in any group. Following challenge with A/Vietnam/1203/2004 (H5N1) virus, only groups B and C exhibited attenuated viral loads leading to 100 % survival. Our data suggest that natural infection with human seasonal strains could potentially provide better heterosubtypic protection against HPAI H5N1 virus infection compared to TIV immunization.

Supplementation of oil-based inactivated H9N2 vaccine with M2e antigen enhances resistance against heterologous H9N2 avian influenza virus infection

Avian influenza virus (AIV) subtype H9N2 has been evolving rapidly and vaccine escape variants have been reported to cause circulation of infections and economic losses. In the present study, we developed and evaluated ectodomain of the AIV matrix 2 (M2e) protein as a supplementing antigen for oil-based inactivated H9N2 vaccine to increase resistance against vaccine escape variants. AIV H9N2 M2e antigen was expressed in Escherichia coli and supplemented to inactivated H9N2 oil emulsion vaccine. Specific pathogen-free chickens received a single injection of inactivated H9N2 oil emulsion vaccines with or without M2e supplementation. At three weeks post vaccination, hemagglutination inhibition tests and enzyme-linked immunosorbent assays were performed to determine serological immune responses. Challenge study using a vaccine escape H9N2 variant was performed to evaluate the efficacy of M2e supplementation. M2e antigen supplemented in oil emulsion vaccine was highly immunogenic, and a single M2e-supplemented vaccination reduced challenge virus replication and shedding more effectively than non-supplemented vaccination.

Mucosal immunization with recombinant adenovirus encoding soluble globular head of hemagglutinin protects mice against lethal influenza virus infection

Influenza virus is one of the major sources of respiratory tract infection. Due to antigenic drift in surface glycoproteins the virus causes annual epidemics with severe morbidity and mortality. Although hemagglutinin (HA) is one of the highly variable surface glycoproteins of the influenza virus, it remains the most attractive target for vaccine development against seasonal influenza infection because antibodies generated against HA provide virus neutralization and subsequent protection against the virus infection. Combination of recombinant adenovirus (rAd) vector-based vaccine and mucosal administration is a promising regimen for safe and effective vaccination against influenza. In this study, we constructed rAd encoding the globular head region of HA from A/Puerto Rico/8/34 virus as vaccine candidate. The rAd vaccine was engineered to express high level of the protein in secreted form. Intranasal or sublingual immunization of mice with the rAd-based vaccine candidates induced significant levels of sustained HA-specific mucosal IgA and IgG. When challenged with lethal dose of homologous virus, the vaccinated mice were completely protected from the infection. The results demonstrate that intranasal or sublingual vaccination with HA-encoding rAd elicits protective immunity against infection with homologous influenza virus. This finding underlines the potential of our recombinant adenovirus-based influenza vaccine candidate for both efficacy and rapid production.

Mucosal vaccination with recombinant adenovirus encoding nucleoprotein provides potent protection against influenza virus infection

Influenza vaccines that target the highly variable surface glycoproteins hemagglutinin and neuraminidase cause inconvenience of having vaccination every year. For this reason, development of universal vaccines targeting conserved viral components is needed. In this study, we generated recombinant adenovirus (rAd) vaccine encoding nucleoprotein (NP) of A/PR/8/34 influenza virus, designated rAd/NP. BALB/c mice were immunized intranasally or sublingually with rAd/NP vaccine and subsequently challenged with lethal doses of heterologous as well as homologous influenza viruses. We found that intranasal immunization of rAd/NP elicited strong mucosal IgA responses as well as stronger CD8 T-cell responses toward immunodominant K^d-restricted NP_147-155 epitope than sublingual immunization. Importantly, only single intranasal but not sublingual immunization of rAd/NP provides potent protection against both homologous and heterologous influenza virus challenges. These results suggest that recombinant rAd/NP could be a universal vaccine candidate for mucosal administration against influenza virus.

Neonatal immunization with respiratory syncytial virus glycoprotein fragment induces protective immunity in the presence of maternal antibodies in mice

Respiratory syncytial virus (RSV) is a major cause of severe lower respiratory tract infections in infants and the elderly worldwide. The significant morbidity and mortality associated with this infection underscores the urgent need for development of RSV vaccine. In this study, we first show that intranasal administration of RSV glycoprotein core fragment (Gcf) to neonatal mice can induce systemic humoral immune responses and protective immunity against RSV without causing lung eosinophilia, although antibody response was shifted to a Th2 response. Next, we examined whether the presence of maternal anti-RSV antibodies would affect the responsiveness and protection efficacy of Gcf in newborn mice, since infants can possess RSV-specific maternal antibodies due to frequent RSV re-infections to adults. Intranasal administration of Gcf induced antibody response and increased IFNγ secretion and protected mice against RSV challenge without severe lung eosinophilia, even in the presence of high levels of RSV-specific maternal antibodies. Thus, our findings suggest that Gcf may be an effective and safe RSV vaccine during the neonatal period.

Immunogenicity and safety of H1N1 influenza hemagglutinin protein expressed in a baculovirus system

Although most influenza vaccines are produced in eggs, new types of vaccines must be developed. In this study, the immunogenicity and safety of a baculovirus-expressed hemagglutinin (HA) of H1N1 influenza virus (Korea/01/2009; designated "HA-Bac-K") was compared with those of a commercially available baculovirus-expressed HA (designated "HA-Bac-C") and an Escherichia coli-expressed HA (designated "HA-E. Coli-K"). HA-Bac-K succeeded in inducing hemagglutination inhibition and neutralization antibodies in mouse and ferret models. The different immunogenicities observed may be attributable to the different expression systems and purification protocols used. Our work suggests that HA expressed in a baculovirus system is an effective and safe candidate influenza vaccine.

Sublingual delivery of vaccines for the induction of mucosal immunity

The mucosal surfaces are constantly exposed to incoming pathogens which can cause infections that result in severe morbidity and/or mortality. Studies have reported that mucosal immunity is important for providing protection against these pathogens and that mucosal vaccination is effective in preventing local infections. For many years, the sublingual mucosa has been targeted to deliver immunotherapy to treat allergic hypersensitivities. However, the potential of vaccine delivery via sublingual mucosal has received little attention until recently. Recent studies exploring such potential have documented the safety and effectiveness of sublingual immunization, demonstrating the ability of sublingual immunization to induce both systemic and mucosal immune responses against a variety of antigens, including soluble proteins, inter particulate antigens, and live-attenuated viruses. This review will summarize the recent findings that address the promising potential of sublingual immunization in proving protection against various mucosal pathogens.

Neonatal immunization with respiratory syncytial virus glycoprotein fragment induces protective immunity in the presence of maternal antibodies in mice (P4277)

Respiratory syncytial virus (RSV) is the major cause of severe lower respiratory tract infections in infants and the elderly worldwide. The significant morbidity and mortality associated with this infection underscores the urgent need for development of an RSV vaccine. In this study, we first show that intranasal administration of RSV glycoprotein core fragment (Gcf) to neonatal mice can induce systemic humoral immune responses and protective immunity against RSV without causing lung eosinophilia, although antibody response was shifted to a Th2 response. Next, we examined whether the presence of maternal anti-RSV antibodies affects the responsiveness and protection efficacy of Gcf in newborn mice, since infants can have RSV-specific maternal antibodies since adults are frequently reinfected with RSV. Intranasal administration of Gcf induced antibody response and IFNγ secretion and protected mice against RSV challenge without lung eosinophilia even in the presence of high levels of RSV-specific maternal antibodies. Thus, our findings suggest that Gcf may be an effective and safe RSV vaccine during the neonatal period.

Prokaryote-expressed M2e protein improves H9N2 influenza vaccine efficacy and protection against lethal influenza A virus in mice

BACKGROUND

Influenza vaccines are prepared annually based on global epidemiological surveillance data. However, since there is no method by which to predict the influenza strain that will cause the next pandemic, the demand to develop new vaccination strategies with broad cross-reactivity against influenza viruses are clearly important. The ectodomain of the influenza M2 protein (M2e) is an attractive target for developing a vaccine with broad cross-reactivity. For these reasons, we investigated the efficacy of an inactivated H9N2 virus vaccine (a-H9N2) mixed with M2e (1xM2e or 4xM2e) proteins expressed in Escherichia coli, which contains the consensus of sequence the extracellular domain of matrix 2 (M2e) of A/chicken/Vietnam/27262/09 (H5N1) avian influenza virus, and investigated its humoral immune response and cross-protection against influenza A viruses.

RESULTS

Mice were intramuscularly immunized with a-H9N2, 1xM2e alone, 4xM2e alone, a-H9N2/1xM2e, or a-H9N2/4xM2e. Three weeks post-vaccination, mice were challenged with lethal homologous (A/ chicken /Korea/ma163/04, H9N2) or heterosubtypic virus (A/Philippines/2/82, H3N2 and A/aquatic bird/Korea/maW81/05, H5N2). Our studies demonstrate that the survival of mice immunized with a-H9N2/1xM2e or with a-H9N2/4xM2e (100% survival) was significantly higher than that of mouse-adapted H9N2 virus-infected mice vaccinated with 1xM2e alone or with 4xM2e alone (0% survival). We also evaluated the protective efficacy of the M2e + vaccine against infection with mouse-adapted H5N2 influenza virus. Protection from death in the control group (0% survival) was similar to that of the 1×M2e alone and 4xM2e alone-vaccinated groups (0% survival). Only 40% of mice vaccinated with vaccine alone survived challenge with H5N2, while the a-H9N2/1×M2e and a-H9N2/4×M2e groups showed 80% and 100% survival following mouse-adapted H5N2 challenge, respectively. We also examined cross-protection against human H3N2 virus and found that the a-H9N2/1×M2e group displayed partial cross-protection against H3N2 (40% survival), whereas vaccine alone, 1×M2e alone, 4×M2e alone, or H9N2/1×M2e groups showed incomplete protection (0% survival) in response to challenge with a lethal dose of human H3N2 virus.

CONCLUSIONS

Taken together, these results suggest that prokaryote-expressed M2e protein improved inactivated H9N2 virus vaccine efficacy and achieved cross-protection against lethal influenza A virus infection in mice.

Sublingual administration of bacteria-expressed influenza virus hemagglutinin 1 (HA1) induces protection against infection with 2009 pandemic H1N1 influenza virus

Influenza viruses are respiratory pathogens that continue to pose a significantly high risk of morbidity and mortality of humans worldwide. Vaccination is one of the most effective strategies for minimizing damages by influenza outbreaks. In addition, rapid development and production of efficient vaccine with convenient administration is required in case of influenza pandemic. In this study, we generated recombinant influenza virus hemagglutinin protein 1 (sHA1) of 2009 pandemic influenza virus as a vaccine candidate using a well-established bacterial expression system and administered it into mice via sublingual (s.l.) route. We found that s.l. immunization with the recombinant sHA1 plus cholera toxin (CT) induced mucosal antibodies as well as systemic antibodies including neutralizing Abs and provided complete protection against infection with pandemic influenza virus A/CA/04/09 (H1N1) in mice. Indeed, the protection efficacy was comparable with that induced by intramuscular (i.m.) immunization route utilized as general administration route of influenza vaccine. These results suggest that s.l. vaccination with the recombinant non-glycosylated HA1 protein offers an alternative strategy to control influenza outbreaks including pandemics.

Induction of BAFF expression by IFN-γ via JAK/STAT signaling pathways in human intestinal epithelial cells

BAFF plays an important role in the development of B cells. Here, we investigated the effect of IFN-γ on BAFF expression in human intestinal epithelial cells. IFN-γ induced soluble and membrane-bound BAFF production in a dose- and time-dependent manner. IFN-γ-induced BAFF release from polarized intestinal epithelial cells was observed in apical and basolateral compartments. JAK I inhibitor suppressed IFN-γ-induced BAFF expression. Moreover, IFN-γ enhanced STAT1 phosphorylation and expression of IRF-1. Transient transfection and reporter gene assay showed that the BAFF promoter region spanning -750 to -500 bp from the translation initiation site was crucial for IFN-γ-induced BAFF expression. Nucleotide sequence analysis revealed a GAS element in the promoter region. ChIP assay confirmed the enhanced binding of phosphorylated STAT1 to the BAFF promoter region at -800 to -601 bp. Furthermore, IFN-γ enhanced DNA binding to GAS and its transcriptional activation, as determined by the EMSA and reporter gene assay. Collectively, these results suggest that IFN-γ induces BAFF expression in human intestinal epithelial cells through JAK/STAT signaling pathways that might activate the GAS and IRF-1-binding element in the BAFF promoter.

Conjugated linoleic acid synthesis-related protein proteasome subunit α 5 (PSMA5) is increased by vaccenic acid treatment in goat mammary tissue

This study was conducted to identify proteins associated with the endogenous synthesis of conjugated linoleic acid (CLA) from trans-vaccenic acid (TVA; trans-11 C18:1, a precursor for CLA endogenous synthesis) in mammary tissues. Six lactating goats were divided into 2 groups. One group was given an intravenous bolus injection of TVA (150mg) twice daily over 4 d; the other group received saline injections. Treatment with TVA increased the concentration of cis-9,trans-11 CLA and TVA in goat milk. Additionally, TVA treatment increased the expression of stearoyl-CoA desaturase (SCD) in mammary tissue. Using 2-dimensional gel electrophoresis and electrospray ionization quadrupole time-of-flight mass spectrometry, 3 proteins affected by infusions of TVA were identified. Proteasome (prosome, macropain) subunit α type 5 (PSMA5) was upregulated, whereas peroxiredoxin-1 and translationally controlled tumor protein 1 were downregulated in TVA-treated animals compared with the vehicle-injected controls. Only the effect of TVA on PSMA5 could be confirmed by Western blot analysis. To further explore the regulation of PSMA5 in mammary epithelial cells when TVA is converted into CLA, we used a differentiated bovine mammary epithelial cell line treated with TVA for 6h. Changes in cis-9,trans-11 CLA concentrations and mRNA expression patterns of both SCD and PSMA5 were monitored. The concentration of cis-9,trans-11 CLA increased after TVA treatment. The mRNA expression level of PSMA5 was significantly elevated to 6h, but SCD mRNA expression only increased in 2h after TVA treatment. These results indicate that PSMA5 is highly expressed in goat mammary tissue and bovine mammary epithelial cells when TVA is converted into CLA. Our data suggest that PSMA5 protein is associated with CLA biosynthesis in mammary tissue.

Sublingual immunization with recombinant adenovirus encoding SARS-CoV spike protein induces systemic and mucosal immunity without redirection of the virus to the brain

Background

Sublingual (s.l.) administration of soluble protein antigens, inactivated viruses, or virus-like particles has been shown to induce broad immune responses in mucosal and extra-mucosal tissues. Recombinant replication-defective adenovirus vectors (rADVs) infect mucosa surface and therefore can serve as a mucosal antigen delivery vehicle. In this study we examined whether s.l. immunization with rADV encoding spike protein (S) (rADV-S) of severe acute respiratory syndrome-associated coronavirus (SARS-CoV) induces protective immunity against SARS-CoV and could serve as a safe mucosal route for delivery of rADV.

Results

Here, we show that s.l. administration of rADV-S induced serum SARS-CoV neutralizing and airway IgA antibodies in mice. These antibody responses are comparable to those induced by intranasal (i.n.) administration. In addition, s.l. immunization induced antigen-specific CD8⁺ T cell responses in the lungs that are superior to those induced by intramuscular immunization. Importantly, unlike i.n. administration, s.l. immunization with rADV did not redirect the rADV vector to the olfactory bulb.

Conclusion

Our study indicates that s.l. immunization with rADV-S is safe and effective in induction of a broad spectrum of immune responses and presumably protection against infection with SARS-CoV.

Effect of maternal immune status on responsiveness of bacillus calmette-gurin vaccination in mouse neonates

OBJECTIVES

Bacillus Calmette-Guérin (BCG) vaccination has proven to be efficient in immunologically naïve infants; however, it has not been investigated that maternal natural exposure to Mycobacterium and/or BCG vaccine could influence the characteristics of immune responses to BCG in newborns. In this study, we analyzed whether the maternal immune status to M tuberculosis (M tb) can affect neonatal immunity to BCG using a mouse model.

METHODS

Neonates were obtained from mice that were previously exposed to live BCG, to live M avium, or to heat-killed M tb H37Rv, and from naïve control mothers. One week after birth, the neonates were divided into two subgroups: one group immunized with live BCG via the subcutaneous route and the other group of neonates sham-treated. Interferon-gamma (IFNγ) secretion in response to in vitro stimulation with heat-killed BCG or purified protein derivative (PPD) was examined. Protection against M tb infection was evaluated by challenging mice nasally with live M tb H37Rv followed by counting colonies from spleen and lung homogenates.

RESULTS

BCG-immunized neonates showed increased IFNγ secretion in response to heat-killed BCG or PPD. All mice in BCG-immunized neonates subgroups showed reduced bacterial burden (colony forming unit) in the lungs when compared with control naive neonate mice. However, no statistically significant difference was observed when comparing BCG-immunized mice born from mothers previously exposed to M avium or immunized with either heat-killed H37Rv or live BCG and mice born from naïve mothers.

CONCLUSION

The maternal immune status to M tb does not appear to impact on the immunogenicity of BCG vaccine in their progeny in our experimental conditions.

Dual role of respiratory syncytial virus glycoprotein fragment as a mucosal immunogen and chemotactic adjuvant

Respiratory syncytial virus (RSV) is a major cause of severe lower respiratory tract disease in infancy and early childhood. Despite its importance as a pathogen, there is no licensed vaccine to prevent RSV infection. The G glycoprotein of RSV, a major attachment protein, is a potentially important target for protective antiviral immune responses and has been shown to exhibit chemotactic activity through CX3C mimicry. Here, we show that sublingual or intranasal immunization of a purified G protein fragment of amino acids from 131 to 230, designated Gcf, induces strong serum IgG and mucosal IgA responses. Interestingly, these antibody responses could be elicited by Gcf even in the absence of any adjuvant, indicating a novel self-adjuvanting property of our vaccine candidate. Gcf exhibited potent chemotactic activity in in vitro cell migration assay and cysteine residues are necessary for chemotactic activity and self-adjuvanticity of Gcf in vivo. Mucosal immunization with Gcf also provides protection against RSV challenge without any significant lung eosinophilia or vaccine-induced weight loss. Together, our data demonstrate that mucosal administration of Gcf vaccine elicits beneficial protective immunity and represents a promising vaccine regimen preventing RSV infection.

Evaluation of protective efficacy of respiratory syncytial virus vaccine against A and B subgroup human isolates in Korea

Human respiratory syncytial virus (HRSV) is a significant cause of upper and lower respiratory tract illness mainly in infants and young children worldwide. HRSV is divided into two subgroups, HRSV-A and HRSV-B, based on sequence variation within the G gene. Despite its importance as a respiratory pathogen, there is currently no safe and effective vaccine for HRSV. In this study, we have detected and identified the HRSV by RT-PCR from nasopharyngeal aspirates of Korean pediatric patients. Interestingly, all HRSV-B isolates exhibited unique deletion of 6 nucleotides and duplication of 60 nucleotides in the G gene. We successfully amplified two isolates ('KR/A/09-8' belonging to HRSV-A and 'KR/B/10-12' to HRSV-B) on large-scale, and evaluated the cross-protective efficacy of our recombinant adenovirus-based HRSV vaccine candidate, rAd/3xG, by challenging the immunized mice with these isolates. The single intranasal immunization with rAd/3xG protected the mice completely from KR/A/09-8 infection and partially from KR/B/10-12 infection. Our study contributes to the understanding of the genetic characteristics and distribution of subgroups in the seasonal HRSV epidemics in Korea and, for the first time, to the evaluation of the cross-protective efficacy of RSV vaccine against HRSV-A and -B field-isolates.

Intranasal immunization with plasmid DNA encoding spike protein of SARS-coronavirus/polyethylenimine nanoparticles elicits antigen-specific humoral and cellular immune responses

Background

Immunization with the spike protein (S) of severe acute respiratory syndrome (SARS)-coronavirus (CoV) in mice is known to produce neutralizing antibodies and to prevent the infection caused by SARS-CoV. Polyethylenimine 25K (PEI) is a cationic polymer which effectively delivers the plasmid DNA.

Results

In the present study, the immune responses of BALB/c mice immunized via intranasal (i.n.) route with SARS DNA vaccine (pci-S) in a PEI/pci-S complex form have been examined. The size of the PEI/pci-S nanoparticles appeared to be around 194.7 ± 99.3 nm, and the expression of the S mRNA and protein was confirmed in vitro. The mice immunized with i.n. PEI/pci-S nanoparticles produced significantly (P < 0.05) higher S-specific IgG1 in the sera and mucosal secretory IgA in the lung wash than those in mice treated with pci-S alone. Compared to those in mice challenged with pci-S alone, the number of B220⁺ cells found in PEI/pci-S vaccinated mice was elevated. Co-stimulatory molecules (CD80 and CD86) and class II major histocompatibility complex molecules (I-A^d) were increased on CD11c⁺ dendritic cells in cervical lymph node from the mice after PEI/pci-S vaccination. The percentage of IFN-γ-, TNF-α- and IL-2-producing cells were higher in PEI/pci-S vaccinated mice than in control mice.

Conclusion

These results showed that intranasal immunization with PEI/pci-S nanoparticles induce antigen specific humoral and cellular immune responses.

Direct multiplex reverse transcription-nested PCR detection of influenza viruses without RNA purification

This paper describes the development a of direct multiplex reverse transcription-nested polymerase chain reaction (PCR) method, devised for simultaneous detection and typing of influenza viruses. This method combines the direct reverse transcription reaction without RNA purification with the enhancement of sensitivity and specificity of nested PCR. The method successfully detected three major human influenza viruses: influenza virus A subtype 1 (H1N1) and subtype 3 (H3N2), and influenza B virus (B). The minimum number of virus particles (pfu/ml) necessary for detection in spiked saliva samples was 200 (H1N1), 140 (H3N2), and 4.5 (B). The method's sensitivity and simplicity will be convenient for use in clinical laboratories for the detection and subtyping of influenza and possibly other RNA viruses.

Conjugated linoleic acids content in M.longissimus dorsi of Hanwoo steers fed a concentrate supplemented with soybean oil, sodium bicarbonate-based monensin, fish oil

We hypothesized that increasing ruminal pH would lead to enrichment of adipose tissue with conjugated linoleic acid (CLA). Twenty-four Korean native (Hanwoo) steers were used to investigate the additive effects of monensin (30ppm, SO-BM) and/or fish oil (0.7%, SO-BMF) in the diets along with soybean oil (7%) and sodium bicarbonate (0.5%, SO-B) on cis-9, trans-11 and trans-10, cis-12 CLAs in adipose tissue. The steers were assigned to randomly four groups of six animals each based on body weight. The control group (CON) was fed a commercial concentrate for the late fattening stage. Supplementation of oil and sodium bicarbonate reduced feed intake and daily gain, and fish oil further decreased feed intake (P<0.001) and daily gain (P<0.087) compared to steers fed other diets. Total CLA and CLA isomers in M.longissimus dorsi were not affected when steers were fed SO-B and SO-BM diets compared with those of steers fed CON and SO-BMF diets. However, total poly unsaturated fatty acids were higher (P=0.03) in steers fed SO than in CON steers.

Body weight reduction in rats by oral treatment with zinc plus cyclo-(His-Pro)

BACKGROUND AND PURPOSE

We have previously shown that treatment with zinc plus cyclo-(His-Pro) (CHP) significantly stimulated synthesis of the insulin degrading enzyme and lowered plasma insulin and blood glucose levels, alongside improving oral glucose tolerance in genetically type 2 diabetic Goto-Kakizaki (G-K) rats and in aged obese Sprague-Dawley (S-D) rats. Thus, we postulated that zinc plus CHP (ZC) treatment might also improve body weight control in these rats. We therefore determined the effects of ZC treatment on body weights in both genetically diabetic, mature G-K rats and non-diabetic, obese S-D rats.

EXPERIMENTAL APPROACH

G-K rats aged 1.5-10 months and non-diabetic overweight or obese S-D rats aged 6-18 months were treated with 0-6 mg CHP plus 0-10 mg zinc L(-1) drinking water for 2-4 weeks, and changes in weight, serum leptin and adiponectin levels, food and water intakes were measured.

KEY RESULTS

The optimal dose of CHP (in combination with zinc) to reduce weight and plasma leptin levels and to increase plasma adiponectin levels was close to 0.1 mg kg(-1) day(-1), in either mature G-K rats and aged overweight or obese S-D rats. Food and water intake significantly decreased in ZC treated rats in both aged S-D rats and mature G-K rats, but not in young S-D and G-K rats.

CONCLUSIONS AND IMPLICATIONS

ZC treatment improved weight control and may be a possible treatment for overweight and obesity.

Intranasal delivery of cholera toxin induces th17-dominated T-cell response to bystander antigens

Cholera toxin (CT) is a potent vaccine adjuvant, which promotes mucosal immunity to protein antigen given by nasal route. It has been suggested that CT promotes T helper type 2 (Th2) response and suppresses Th1 response. We here report the induction of Th17-dominated responses in mice by intranasal delivery of CT. This dramatic Th17-driving effect of CT, which was dependent on the B subunit, was observed even in Th1 or Th2-favored conditions of respiratory virus infection. These dominating Th17 responses resulted in the significant neutrophil accumulation in the lungs of mice given CT. Both in vitro and in vivo treatment of CT induced strongly augmented IL-6 production, and Th17-driving ability of CT was completely abolished in IL-6 knockout mice, indicating a role of this cytokine in the Th17-dominated T-cell responses by CT. These data demonstrate a novel Th17-driving activity of CT, and help understand the mechanisms of CT adjuvanticity to demarcate T helper responses.

Direct detection of Shigella flexneri and Salmonella typhimurium in human feces by real-time PCR

We have established a SYBR Green-based realtime PCR method using AnyDirect solution, which enhances PCR from whole blood, for direct amplification of the virA gene of Shigella flexneri and the invA gene of Salmonella typhimurium from human feces without prior DNA purification. When we compared the efficiency of conventional or realtime PCR amplification of the virA and invA genes from the supernatant of boiled feces supplemented with S. flexneri and S. typhimurium in the presence or absence of AnyDirect solution, amplification products were detected only in reactions to which AnyDirect solution had been added. The detection limit of real-time PCR was 1 x 10(4) CFU/g feces for S. flexneri and 2 x 10(4) CFU/g feces for S. typhimurium this sensitivity level was comparable to other studies. Our real-time PCR assay with AnyDirect solution is simple, rapid, sensitive, and specific, and allows simultaneous detection of S. flexneri and S. typhimurium directly from fecal samples without prior DNA purification.

The clinical and immunogenetic characteristics of adult-onset type 1 diabetes mellitus in Korea

Although the HLA class II alleles and immunological abnormalities are associated with type 1 diabetes mellitus (T1DM) in all racial groups, there are considerable variations in the genotypes and the prevalence of autoantibodies. In order to investigate the characteristics of the immunogenetic patterns and to use these as an early diagnostic tool and guideline for a therapeutic plan, we examined the clinical characteristics and the patterns of anti-GAD antibody (GADA), IA-2 antibody (IA-2A), HLA-DR and HLA-DQ in Korean adult-onset T1DM patients. Adult-onset patients had higher serum C-peptide levels than child-onset patients. In adult-onset patients, the prevalence of GADA and IA-2A were 59.5% and 15.3% respectively, and increased frequencies of HLADR4 and-DR9 were found. The frequencies of HLADQA1,-DQB1 and-DQ heterodimers were similar to those of the control, but child-onset patients had high frequencies of the HLA-DR3,-DR4,-DR9, DQA1*0301, DQA1*0501 and DQB1*0201 genotypes. In conclusion, Korean adult-onset T1DM patients had a lower prevalence of GADA, which was comparable to that found in Caucasian patients. The detection of GADA might help to predict the insulin dependency of adult-onset diabetes. Difference in the frequencies of diabetes associated with HLA type suggests that there might be a heterogeneity in the pathogenesis of diabetes according to the age of onset.

Characterization of immune responses induced by intramuscular vaccination with DNA vaccines encoding measles virus hemagglutinin and/or fusion proteins

Measles virus (MV) hemagglutinin (MV-H) and fusion (MV-F) proteins induce plaque reduction neutralizing (PRN) antibodies and cell-mediated immune responses that protect against clinical measles. DNA vaccines that encode MV-H and MV-F are being investigated as a new generation of measles vaccine to protect infants too young to receive currently licensed attenuated measles vaccines. However, it is unclear whether DNA vaccines encoding both MV-H and MV-F act synergistically to induce stronger immunity than immunization with plasmids encoding MV-H or MV-F alone. To address this question, we generated Sindbis virus-based pSINCP DNA vaccines that encode either MV-H or MV-F alone or bicistronic or fusion system vectors that encode both MV-H and MV-F (to mimic MV infection where both MV-H and MV-F proteins are expressed by the same mammalian cell). Mice immunized with DNA vaccine encoding MV-H alone developed significantly greater PRN titers than mice immunized with bicistronic constructs. Interestingly, the presence of MV-F in the bicistronic constructs stimulated serum MV-specific immunoglobulin G of reduced avidity. By contrast, mice immunized with bicistronic constructs induced equivalent or higher levels of MV-specific gamma interferon responses than mice immunized with DNA vaccine encoding MV-H alone. These data will help guide the design of DNA-based MV vaccines to be used early in life in a heterologous prime-boost strategy.

Effects of cyclo (his-pro) plus zinc on glucose metabolism in genetically diabetic obese mice

AIMS

The specific objective of this study was to determine acute and long-term effects of cyclo (his-pro) (CHP) plus zinc and l-histidine (CZH) treatment on glucose metabolism in genetically obese (ob/ob), type 2 diabetic mice.

METHODS

Acute effects of 0.3 mg of CHP plus 10 mg of zinc and 0.5 mg of l-histidine/kg body weight (BW) on fed blood glucose concentrations and 3-h average of above fasting blood glucose concentrations (TAFGCs), an index of oral glucose tolerance test, in lean and ob/ob mice were determined. To evaluate long-term effects of CZH on TAFGCs, lean and ob/ob mice were treated with drinking water containing increasing doses of CHP (0, 0.5, 1.0 or 1.5 mg/l) plus 10 mg zinc and 0.5 mg of l-histidine/l for 3 weeks. During the treatment period, fed blood glucose concentrations, BW and food and water intake were determined. At the end of the treatment, fasting blood glucose concentrations, TAFGC and fed plasma insulin concentrations were determined.

RESULTS

Blood glucose concentrations significantly decreased when CZH was administered acutely via gastric gavage in food-deprived ob/ob mice. Similarly, 1.0 mg/l CHP treatment of mice with fixed amounts of 10 mg zinc and 0.5 mg l-histidine/l was optimal to decrease fed blood glucose and plasma insulin concentrations during a 3-week treatment period in ob/ob mice. TAFGC values in these mice also improved most significantly with the same combination of CHP, zinc and l-histidine used to test for fed blood glucose and plasma insulin levels. Fasting blood glucose concentrations and BW gains also decreased in ob/ob mice treated with 1.0 mg of CHP/l plus the same amount of zinc and l-histidine used in the above experiments. No effects of CZH treatment in lean mice were observed.

CONCLUSIONS

CZH is effective in decreasing blood glucose concentrations in genetically obese (ob/ob), type 2 diabetic mice. These data support our working hypothesis that CZH may be an important anti-hyperglycaemic agent.

Effects of arachidonic acid plus zinc on glucose disposal in genetically diabetic (ob/ob) mice

AIM

The present study is designed to determine whether arachidonic acid (AA) plus zinc improves clinical signs of diabetes in genetically diabetic ob/ob mice.

METHODS

In the first study, effects of acute administration of AA plus zinc on glucose disposal were determined in ob/ob and lean mice (n = 6 each). In the second study, ob/ob and lean mice were treated with increasing doses of AA plus zinc for 2 weeks (n = 5 each). Postprandial and fasting blood glucose concentrations, three-hour-area-average above fasting glucose concentration (TAFGC), water and food intake, body weight and plasma insulin concentrations were measured.

RESULTS

Acute administration of AA plus zinc significantly increased glucose disposal in ob/ob mice. In the second study, postprandial and fasting blood glucose concentrations, TAFGC, and water and food intake in ob/ob mice treated with AA plus zinc for 2 weeks were significantly decreased compared with those in mice given no AA. Plasma insulin concentrations in both lean and ob/ob mice were not changed by AA treatment in drinking water.

CONCLUSIONS

AA plus zinc in drinking water is effective in decreasing blood glucose levels in obese mice. These results indicate that use of these compounds should be considered as a dietary supplement to control hyperglycaemia in patients with type II diabetes.

Effects of arachidonic acid and cyclo (his-pro) on zinc transport across small intestine and muscle tissues

Previously we have shown that arachidonic acid (AA) plus zinc or cyclo (his-pro) (CHP) plus zinc improve clinical signs of diabetes in streptozotocin-induced diabetic rats. Since streptozotocin destroys pancreatic beta-cells, we hypothesize that the effect of either AA or CHP, plus zinc on glucose metabolism is via mobilization of intracellular zinc which in turn stimulates glucose uptake by peripheral tissues. We now report the relationship between zinc and AA and between zinc and CHP in controlling zinc influx and efflux across hindlimb muscle cells isolated from three-month old rats. Although CHP increased muscle zinc influx in a dose-dependent manner, AA was not effective. However, AA was more effective in stimulating zinc efflux than CHP. We have previously demonstrated that AA stimulates intestinal zinc uptake and absorption, and now present evidence that CHP also influences intestinal zinc transport. These results suggest that both AA and CHP affect glucose uptake in muscle cells via stimulating intestinal zinc absorption and muscle cell zinc flux.

Synergistic antidiabetic activities of zinc, cyclo (his-pro), and arachidonic acid

Previous studies have already shown that prostate extract (PE) has antidiabetic activity when given to animals and humans. In this study, we explore whether this antidiabetic activity is related to the high concentrations of zinc, cyclo (his-pro) (CHP), and the prostaglandin precursor, arachidonic acid (AA), in prostate tissue. When streptozotocin-induced diabetic rats were given drinking water containing 10 mg/L zinc and 100 mg/L PE for 3 weeks, fasting blood glucose levels and glucose clearance rates, but not plasma insulin levels, were significantly lower than at pretreatment. In subsequent experiments, blood glucose levels in rats given PE for 3 weeks were significantly lower than in rats given distilled water or 10 mg/L zinc alone. However, in rats given 100 mg/L CHP with zinc, blood glucose levels were also lower than in rats given PE alone. Time-course studies in diabetic rats given drinking water containing 20 mg/L Zn, 20 mg/L L-histidine, and 10 mg/L CHP showed that blood glucose levels dropped 209 +/- 53 mg/dL in 1 day and stayed low for 2 weeks. When CHP was replaced with 100 mg AA/L, blood glucose levels dropped 230 +/- 64 mg/dL in 5 days, but returned to the original values 11 days later. Growth rate improved and water consumption decreased significantly in CHP- and AA-treated diabetic rats. High intake of L-histidine and testosterone increased blood glucose concentrations in diabetic rats. To determine optimal dosages of CHP and AA, we gave rats drinking water containing 10 mg/L Zn and 0.5 mg/L L-histidine with various concentrations of CHP or AA. The most effective doses for reducing blood glucose levels were 0.32 mg CHP/kg/day and 11 mg AA/kg/day. These data suggest that the active antidiabetic ingredients in the PE are CHP, zinc, and AA or its precursors.

US identification of the anal sphincter complex and levator ani muscle in neonates: infracoccygeal approach

PURPOSE

To identify the anal sphincter complex and levator ani muscle at transperineal ultrasonography (US) with the infracoccygeal approach.

MATERIALS AND METHODS

Infracoccygeal US was performed with a 7-MHz linear-array transducer in 40 healthy neonates. The babies were placed in the supine position, and both legs were drawn up to the chest. The buttocks were accordingly lifted up. The approach site was just inferior to the coccyx and posterior to the anus. Scanning was performed to obtain transverse images of the anorectal area. The thickness of the anal sphincter complex and the puborectalis muscle were measured.

RESULTS

Infracoccygeal US revealed the internal anal sphincter (IAS), the external anal sphincter (EAS), and the puborectalis muscle in all babies. The IAS and EAS were depicted as inner and outer hypoechoic ringlike structures, respectively. A round, hyperechoic space (intersphincteral space) was present between the hypoechoic IAS and EAS. The puborectalis muscle was identified as a U-shaped hypoechoic structure. The bulbocavernosus and ischiocavernous muscles were also identified. Mean thicknesses were as follows: IAS, 1.3 mm +/- 0.3 (SD) (range, 0.8-1.9 mm); EAS, 1.6 mm +/- 0.3 (range, 1.2-2.3 mm); and puborectalis muscle, 1.1 mm +/- 0.3 (range, 0.6-1.9 mm).

CONCLUSION

Infracoccygeal transperineal US is an excellent diagnostic modality for demonstrating the anal sphincter complex and levator ani muscle in neonates.

Drug-induced suppression of phosphorylase kinase activity correlates with resolution of psoriasis as assessed by clinical, histological and immunohistochemical parameters

BACKGROUND

Phosphorylase kinase (PhK), also known as adenosine triphosphate (ATP)-phosphorylase b phosphotransferase, integrates multiple calcium/calmodulin-dependent signalling pathways, including those involved in cell migration and cell proliferation, while coupling these pathways to glycogenolysis and ATP-dependent phosphorylation, thus ensuring continuing energy supply for these activities.

OBJECTIVES

Our laboratory recently reported correlation of elevated PhK activity with psoriatic activity. This study further evaluates the significance of drug-induced suppression of PhK activity on psoriatic activity.

PATIENTS AND METHODS

PhK activity was assayed in four groups, each with 10 patients: (i) active untreated psoriasis; (ii) resolving psoriasis treated by calcipotriol (Dovonex(R), Bristol Myers Squibb, Princeton, NJ, U.S.A. ), a vitamin D3 analogue and an indirect inhibitor of PhK; (iii) curcumin (diferuloylmethane), a selective PhK inhibitor; and (iv) 10 normal non-psoriatic subjects.

RESULTS

PhK activity in units mg-1 protein was highest in active untreated psoriasis (1204 +/- 804.3; mean +/- SD), lower in the calcipotriol-treated group (550.7 +/- 192. 9), lower in curcumin-treated group (207.2 +/- 97.6), and lowest in normal skin (105.4 +/- 44.6). One-way analysis of variance performed on log-transformed PhK activity measure showed significant differences among the four groups, F3,36 = 48.79, P < 0.0001. Decreased PhK activity in curcumin-and calcipotriol-treated psoriasis was associated with corresponding decreases in keratinocyte transferrin receptor (TRR) expression, severity of parakeratosis and density of epidermal CD8+ T cells.

CONCLUSIONS

Our results demonstrate that drug-induced suppression of PhK activity is associated with resolution of psoriatic activity as assessed by clinical, histological and immunohistochemical criteria, and support the hypothesis that effective antipsoriatic activity may be achieved through modulation of PhK activity.

Effects of a hexameric deoxyriboguanosine run conjugation into CpG oligodeoxynucleotides on their immunostimulatory potentials

CpG oligodeoxynucleotides (ODNs) are promising immunomodulatory agents for treating human diseases and vaccine development. Phosphodiester CpG ODNs were demonstrated to have poor immunostimulatory potentials for cytokine production. However, the conjugation of consecutive deoxyriboguanosine residues, called a dG run, at the 3' terminus of phosphodiester CpG ODNs significantly enhanced TNF-alpha and IL-12 production from mouse splenic dendritic cells (DCs). The optimal induction of cytokine production was achieved by the addition of a hexameric dG (dG6) run. In contrast, the existence of a dG6 run either at the 5' terminus of phosphodiester CpG ODNs or at the 3' terminus of phosphorothioate CpG ODNs diminished CpG-mediated cytokine induction, suggesting that the effects of a dG run depend on its location and the chemical property of the ODN backbone, respectively. In addition, we provided the evidence that the conjugation of a dG6 run caused the structural transformation of CpG ODNs, which facilitates their targeting into mouse APCs such as splenic DCs, B cells, and peritoneal macrophages with a scavenger receptor type A ligand specificity. Among primary APCs, DCs were the most potent for CpG ODN-mediated IL-12 production. Furthermore, we demonstrated that the conjugation of a dG6 run into the 3' terminus of phosphodiester CpG ODNs was crucial for their ability to generate Th1 immunity in vivo. Thus, the conjugation of a dG6 run into phosphodiester CpG ODNs would be an alternative way to optimize their immunostimulatory potentials in vitro and in vivo.

Systemic toxicity of topical and periocular corticosteroid therapy in an 11-year-old male with posterior uveitis

PURPOSE

To report a case of systemic corticosteroid toxicity resulting from topical and periocular therapy.

METHODS

Treatment and follow-up of an 11-year-old male with uveitis are illustrated. Initial presentation of the patient was bilateral iridocyclitis, for which he was treated with prednisolone acetate 1% every 2 hours for 6 months. Subsequently, posterior uveitis developed, necessitating posterior subtenon injections.

RESULTS

After initial topical corticosteroid therapy, the patient developed a cushingoid habitus accompanied by increased lanugo hair, acanthosis nigricans, posterior subcapsular lens opacities, and increased intraocular pressure. Cushingoid stigmata worsened after administration of posterior subtenon injection of corticosteroids. The patient's truncal obesity worsened, and his linear growth stopped.

CONCLUSIONS

Systemic toxic effects may develop as a result of topical and local use of ophthalmic corticosteroid preparations in susceptible patients.

Characterization of reactivation of cytomegalovirus retinitis in patients healed after treatment with highly active antiretroviral therapy

PURPOSE

To delineate the immune parameters associated with reactivation of cytomegalovirus (CMV) retinitis in patients for whom highly active antiretroviral therapy (HAART) was not successful.

METHODS

Prospective, longitudinal observational study of a cohort of 102 patients with CMV retinitis treated with HAART and being followed up at the AIDS Ocular Research Unit of the University of California, San Diego from November 1995 to November 1998. The study included serial clinical and fundus photographic examinations with CD4 T-lymphocyte counts and HIV viral load measurements.

RESULTS

Forty-seven of the 102 patients with CMV retinitis responded to HAART. Thirty-five of the patients were successfully withdrawn from anti-CMV therapy. During a median follow-up of 74.71 weeks (range, 4.86-144 weeks) after discontinuation of anti-CMV therapy, four patients experienced a reactivation of CMV retinitis. In each case, the CD4 count decreased before reactivation to a median of 31.5 cells/mm3 (mean, 31.25 cells/mm3; range, 23-39 cells/mm3). The association between the CD4 count decreasing to less than 50 cells/mm3 and reactivation of CMV retinitis was statistically significant (P < 0.0003).

CONCLUSION

Four patients treated with HAART experienced reactivation of CMV retinitis as their CD4 count decreased. The threshold CD4 count below which reactivation of CMV retinitis occurred in patients for whom HAART was not successful appeared to be 50 cells/mm3. Despite an initial response to HAART, patients are still at risk for reactivation of CMV retinitis if their CD4 count decreases to less than 50 cells/mm3. The HIV viral load did not appear to predict CMV reactivation.