The reported coverage rates of first and second doses of measles containing vaccine (MCV) are almost 95% in China, while measles cases are constantly being reported. This study evaluated the vaccine coverage, timeliness, and barriers to immunization of MCV1 and MCV2 in children aged from 8–48 months.
We assessed 718 children aged 8–48 months, of which 499 children aged 18–48 months in September 2011. Face to face interviews were administered with children’s mothers to estimate MCV1 and MCV2 coverage rate, its timeliness and barriers to vaccine uptake.
The coverage rates were 76.9% for MCV1 and 44.7% for MCV2 in average. Only 47.5% of surveyed children received the MCV1 timely, which postpone vaccination by up to one month beyond the stipulated age of 8 months. Even if coverage thus improves with time, postponed vaccination adds to the pool of unprotected children in the population. Being unaware of the necessity for vaccination and its schedule, misunderstanding of side-effect of vaccine, and child being sick during the recommended vaccination period were significant preventive factors for both MCV1 and MCV2 vaccination. Having multiple children, mother’s education level, household income and children with working mothers were significantly associated with delayed or missing MCV1 immunization.
To avoid future outbreaks, it is crucial to attain high coverage levels by timely vaccination, thus, accurate information should be delivered and a systematic approach should be targeted to high-risk groups.
The excision of uracil bases from DNA is accomplished by the enzyme uracil DNA glycosylase (UNG). Recognition of uracil bases in free DNA is facilitated by uracil base pair dynamics, but it is not known whether this same mechanistic feature is relevant for detection and excision of uracil residues embedded in nucleosomes. Here we investigate this question using nucleosome core particles (NCPs) generated from X. laevis histones and the high-affinity “Widom 601” positioning sequence. The reactivity of uracil residues in NCPs under steady-state multiple turnover conditions was generally decreased as compared to free 601 DNA, mostly due to anticipated steric effects of histones. However, some sites in NCPs had equal or even greater reactivity than free DNA, and the observed reactivities were not readily explained by simple steric considerations, or by global DNA unwrapping models for nucleosome invasion. In particular, some reactive uracils were found in occluded positions, while some unreactive uracils were found in exposed positions. One feature of many exposed reactive sites is a wide DNA minor groove, which allows penetration of a key active site loop of the enzyme. In single-turnover kinetic measurements, multi-phasic reaction kinetics were observed for several uracil sites, where each kinetic transient was independent of the UNG concentration. These kinetic measurements, and supporting structural analyses, support a mechanism where some uracils are transiently exposed to UNG by local, rate-limiting nucleosome conformational dynamics, followed by rapid trapping of the exposed state by the enzyme. We present structural models and plausible reaction mechanisms for the reaction of UNG at three distinct uracil sites in the NCP.
Some syphilis patients remain in a serologically active state after the recommended therapy. We currently know too little about the characteristics of this serological response.
We conducted a cohort study using the clinical database from Zhongshan Hospital, Medical College of Xiamen. In total, 1,327 HIV-negative patients with primary, secondary, latent, and tertiary syphilis were enrolled. Bivariate and multivariate analyses were utilised to identify factors associated with a serological cure and serofast state in syphilis patients one year after therapy. Chi-square tests were used to determine the differences in the serological cure rate across different therapy time points.
One year after the recommended therapy, 870 patients achieved a serological cure, and 457 patients (34.4%) remained in the serofast state. The serological cure rate increased only within the first 6 months. The bivariate analysis indicated that male or younger patients had a higher likelihood of a serological cure than female or older patients. Having a baseline titre ≤1∶2 or ≥1∶64 was associated with an increased likelihood of a serological cure. The serological cure rate decreased for the different disease stages in the order of primary, secondary, latent, and tertiary syphilis. A distinction should be drawn between early and late syphilis. The multivariate analysis indicated that a serological cure was significantly associated with the disease phase, gender, age, and baseline rapid plasma reagin (RPR) titre.
The serofast state is common in clinical work. After one year of the recommended therapy, quite a few syphilis patients remained RPR positive. The primary endpoint of the study indicated that disease phase, gender, age and baseline RPR titre were crucial factors associated with a serological cure.
Risk perception is a reported predictor of vaccination uptake, but which measures of risk perception best predict influenza vaccination uptake remain unclear.
During the main influenza seasons (between January and March) of 2009 (Wave 1) and 2010 (Wave 2),505 Chinese students and employees from a Hong Kong university completed an online survey. Multivariate logistic regression models were conducted to assess how well different risk perceptions measures in Wave 1 predicted vaccination uptake against seasonal influenza in Wave 2.
The results of the multivariate logistic regression models showed that feeling at risk (β = 0.25, p = 0.021) was the better predictor compared with probability judgment while probability judgment (β = 0.25, p = 0.029 ) was better than beliefs about risk in predicting subsequent influenza vaccination uptake. Beliefs about risk and feeling at risk seemed to predict the same aspect of subsequent vaccination uptake because their associations with vaccination uptake became insignificant when paired into the logistic regression model. Similarly, to compare the four scales for assessing probability judgment in predicting vaccination uptake, the 7-point verbal scale remained a significant and stronger predictor for vaccination uptake when paired with other three scales; the 6-point verbal scale was a significant and stronger predictor when paired with the percentage scale or the 2-point verbal scale; and the percentage scale was a significant and stronger predictor only when paired with the 2-point verbal scale.
Beliefs about risk and feeling at risk are not well differentiated by Hong Kong Chinese people. Feeling at risk, an affective-cognitive dimension of risk perception predicts subsequent vaccination uptake better than do probability judgments. Among the four scales for assessing risk probability judgment, the 7-point verbal scale offered the best predictive power for subsequent vaccination uptake.
Immunization against influenza is considered an essential public health intervention to control both seasonal epidemics and pandemic influenza. According to the World Health Organization (WHO), there are five key policy and three key programmatic issues that decision-makers should consider before introducing a vaccine. These are (a) public health priority, (b) disease burden, (c) efficacy, quality and safety of the vaccine, (d) other inventions, (e) economic and financial issues, (f) vaccine presentation, (g) supply availability and (h) programmatic strength. We analyzed the body of evidence currently available on these eight issues in the WHO Western Pacific Region.
Studies indexed in PubMed and published in English between 1 January 2000 and 31 December 2010 from the 37 countries and areas of the Western Pacific Region were screened for keywords pertaining to the five policy and three programmatic issues. Studies were grouped according to country income level and vaccine target group. There were 133 articles that met the selection criteria, with most (90%) coming from high-income countries. Disease burden (n = 34), vaccine efficacy, quality and safety (n = 27) and public health priority (n = 27) were most frequently addressed by studies conducted in the Region. Many studies assessed influenza vaccine policy and programmatic issues in the general population (42%), in the elderly (24%) and in children (17%). Few studies (2%) addressed the eight issues relating to pregnant women.
The evidence for vaccine introduction in countries and areas in this Region remains limited, particularly in low- and middle-income countries that do not currently have influenza vaccination programmes. Surveillance activities and specialized studies can be used to assess the eight issues including disease burden among vaccine target groups and the cost-effectiveness of influenza vaccine. Multi-country studies should be considered to maximize resource utilization for cross-cutting issues such as vaccine presentation and other inventions.
The HIV-1 envelope glycoprotein (Env) gp41 plays a crucial role in the viral fusion process. The peptides derived from the C-terminal heptad repeat (CHR) of gp41 are potent HIV fusion inhibitors. However, the activity of these anti-HIV-1 peptides in vivo may be attenuated by their induction of anti-gp41 antibodies. Thus, it is essential to identify antiviral peptides or proteins with low, or no, immunogenicity to humans. Here, we found that the C-terminal fragment (aa 462–521) of the human POB1 (the partner of RalBP1), designated C60, is an HIV-1 fusion inhibitor. It bound to N36, the peptide derived from the N-terminal heptad repeat (NHR) of gp41, and to the six-helix bundle (6-HB) formed by N36 and C34, a CHR-peptide, but it did not bind to C34. Unlike the CHR-peptides, C60 did not block gp41 6-HB formation. Rather, results suggest that C60 inhibits HIV-1 fusion by binding to the 6-HB, in particular, the residues in the gp41 NHR domain that are exposed on the surface of 6-HB. Since 6-HB plays a crucial role in the late stage of fusion between the viral envelope and endosomal membrane during the endocytic process of HIV-1, C60 may serve as a host restriction factor to suppress HIV-1 entry into CD4+ T lymphocytes. Taken together, it can be concluded from these results that C60 can be used as a lead for the development of anti-HIV-1 therapeutics or microbicides for the treatment and prevention of HIV-1 infection, as well as a molecular probe to study the fusogenic mechanism of HIV-1.
The Rosetta molecular modeling software package provides experimentally tested and rapidly evolving tools for the 3D structure prediction and high-resolution design of proteins, nucleic acids, and a growing number of non-natural polymers. Despite its free availability to academic users and improving documentation, use of Rosetta has largely remained confined to developers and their immediate collaborators due to the code’s difficulty of use, the requirement for large computational resources, and the unavailability of servers for most of the Rosetta applications. Here, we present a unified web framework for Rosetta applications called ROSIE (Rosetta Online Server that Includes Everyone). ROSIE provides (a) a common user interface for Rosetta protocols, (b) a stable application programming interface for developers to add additional protocols, (c) a flexible back-end to allow leveraging of computer cluster resources shared by RosettaCommons member institutions, and (d) centralized administration by the RosettaCommons to ensure continuous maintenance. This paper describes the ROSIE server infrastructure, a step-by-step ‘serverification’ protocol for use by Rosetta developers, and the deployment of the first nine ROSIE applications by six separate developer teams: Docking, RNA de novo, ERRASER, Antibody, Sequence Tolerance, Supercharge, Beta peptide design, NCBB design, and VIP redesign. As illustrated by the number and diversity of these applications, ROSIE offers a general and speedy paradigm for serverification of Rosetta applications that incurs negligible cost to developers and lowers barriers to Rosetta use for the broader biological community. ROSIE is available at http://rosie.rosettacommons.org.
B-1 cells are innate-like cells that play important roles in host defense against infection. However, the function of B-1 cells in fungi infection remains unclear. Previously we produced IgH transgenic mice TgVH3B4 with VH derived from a natural antibody 3B4 that can identify C. albicans, and found that TgVH3B4 mice were resistant to intraperitoneal (i. p.) and intravenous C. albicans infection. Most of the peritoneal cavity (PEC) B-1 cells in TgVH3B4 mice express transgenic BCR that binds C. albicans. In the present study, we explored the response of B-1 cells to C. albicans infection by applying i. p. inoculation of fungi in TgVH3B4 mice. We found that C. albicans was cleared more efficiently in TgVH3B4 mice after i. p. inoculation than that of littermate control. The level of C. albicans-reactive IgM in PEC of TgVH3B4 mice was much higher than that of control, and the number of B-1a B cells was also elevated in TgVH3B4 mice, which was mainly due to enhanced proliferation of B-1 cells. Additionally, numbers of C. albicans-specific B cells increased greatly in TgVH3B4 mice after C. albicans inoculation. Our data suggested that in situ IgM production and clonal expansion of B-1 cells in PEC participate in host defense against C. albicans infection.
Cystic echinococcosis is a global parasitic disease caused by infection with Echinococcus granulosus larvae with potentially life-threatening complications in humans. To date, the status of the immune cells believed to be associated with the pathogenicity of E. granulosus infection has not been demonstrated clearly.
In this study, we developed a multiplex flow cytometry assay to investigate the systemic immune status of innate and adaptive immunity at 30, 180, 360 days post-infection (dpi) in mice infected with E. granulousus. At 30 dpi, an increase in the number of CD11b+ and CD11c+ antigen-presenting cells (APCs) was observed. This was accompanied by the slight down-regulated expression of the co-stimulatory molecule MHC-II, indicating the impairment of APCs in early infection through the release of secretory-excretory products. In all infected groups, we observed a significant increase in innate immune cells, including APCs and GR-1+ cells, and a dramatic increase in the myeloid-derived suppressor cells (MDSC) expressing CD11b+/GR-1+. Moreover, the upregulation of the activated markers CD69, CD44, CD40L, and the downregulation of CD62L were observed in the CD4+ and CD8+ T cells following infection. Regulatory T cells expressing CD4+/CD25+/FoxP3+ increased significantly over the course of infection.
Our findings demonstrate that the microenvironment in the peripheral immune system after E. granulosus infection changes in subtle but detectably ways, especially during the persistent period of infection. We found that T cells were activated following infection, but observed that the significant increase of immunosuppressive cells such as MDSC and Treg cells could inhibit T cell response to E. granulosus antigens. We suggest these cells may play a neglected but key role in the downregulation of the immune response in long-term parasitic infection. Understanding the basic functions and temporal interactions of these immunosuppressive cells will pave the way for new strategies of parasite vaccine design.
In recent years, the population of men who have sex with men (MSM) have become the most significant increasing group of HIV-1 transmission in China. To identify new recombinant strains and transmission patterns of HIV-1 in Chinese MSM population, a cross-sectional investigation of MSM in Anhui Province (in south-eastern China) was performed in 2011. The diagnosed AIDS case rate, CD4 T-cell counts, HIV subtypes, and origin of the recombinant strains were investigated in 138 collected samples. The phylogenetic and bootscan analyses demonstrated that, apart from three previously reported circulating strains (CRF07_BC, CRF01_AE, subtype B), various recombinant strains among subtype B, subtype C, CRF01_AE, and CRF07_BC were simultaneously identified in Chinese MSM for the first time. The introducing time of B subtype in Chinese MSM populations was estimated in 1985, CRF01_AE in 2000, and CRF07_BC in 2003; the latter two account for more than 85% of MSM infections. Notably, in comparison with B subtype infections in Anhui MSM, CRF01_AE, with the highest prevalence rate, may accelerate AIDS progression. Over half of patients (56%) infected with new recombinant strains infection are diagnosed as progression into AIDS. Both Bayes and phylogenetic analyses indicated that there was active HIV transmission among MSM nationwide, which may facilitate the transmission of the new 01B recombinant strains in MSM. In conclusion, new recombinant strains and active transmission were identified in the Chinese MSM population, which may lead to a new alarming HIV pandemic in this population due to the increased pathogenesis of the newly emerging strains.
The highly pathogenic avian influenza (HPAI) H5N1 viruses, especially the laboratory-generated H5N1 mutants, have demonstrated the potential to cross the species barrier and infect mammals and humans. Consequently, the design of an effective and safe anti-H5N1 vaccine is essential. We previously demonstrated that the full-length hemagglutinin 1 (HA1) could induce significant neutralizing antibody response and protection. Here, we intended to identify the critical neutralizing domain (CND) in an optimal conformation that can elicit strong cross-neutralizing antibodies and protection against divergent H5N1 strains. We thus constructed six recombinant proteins covering different regions of HA1 of A/Anhui/1/2005(H5N1), each of which was fused with foldon (Fd) and Fc of human IgG. We found that the critical fragment fused with Fd/Fc (HA-13–263-Fdc, H5 numbering) that could elicit the strongest neutralizing antibody response is located in the N-terminal region of HA1 (residues 13–263), which covers the receptor-binding domain (RBD, residues 112–263). We then constructed three additional recombinants fused with Fd plus His tag (HA-13–263-Fd-His), Fc only (HA-13–263-Fc), and His tag only (HA-13–263-His), respectively. We found that the HA-13–263-Fdc, which formed an oligomeric conformation, induced the strongest neutralizing antibody response and cross-protection against challenges of two tested H5N1 virus strains covering clade 1: A/VietNam/1194/2004 (VN/1194) or clade 2.3.4: A/Shenzhen/406H/06 (SZ/406H), while HA-13–263-Fc dimer and HA-13–263-Fd-His trimer elicited higher neutralizing antibody response and protection than HA-13–263-His monomer. These results suggest that the oligomeric form of the CND containing the RBD can be further developed as an effective and safe vaccine for cross-protection against divergent strains of H5N1 viruses.
As one of prevalence HIV-1 strains in IDUs in Asia, the origination and full transmission map of CRF07_BC is of great interested and remains unclear. In the study, we collected 769 CRF07_BC derived sequences (including 45 sequences generated in our laboratory) from 12 provinces in China for reconstructing transmission map. Meanwhile, ample historic epidemic evidences were also reviewed to assist sequences analysis.
In the study, we collected 769 CRF07_BC derived sequences and identified 138 independent sequences from 12 provinces in China for subsequent phylogeographic tree analysis, Bayes Factor test and the estimation of state tMRCA. The analyses demonstrated that CRF07_BC was originated in 1993 in IDU in Yunnan province and then initially spread to Guangxi (eastern neighbor to Yunnan) in 1994, to Xinjiang (northwest) in 1995 and to Sichuan (northern neighbor to Yunnan) in 1996. The subsequent transmissions occurred from Yunnan to Liaoning (northeast) in 1997 and to Jiangsu in 1998. Interestingly, after the early introduction of CRF07_BC into Guangxi, Xinjiang and Sichuan, these three regions served as secondary epicenters for further spreading into Gansu, Ningxia, Qinghai, Beijing and Hunan during 1999–2001. These analyzed results are in accordance with early epidemic investigations.
Our data not just reconstructed the migration map of CRF07_BC, but also firstly revealed the active roles of these secondary epicenters in the dynamic migration of CRF07_BC in China.
Vaccination has proven effective in controlling many infectious diseases. However, differential effectiveness with regard to pathogen genotype is a frequent reason for failures in vaccine development. Often, insufficient immune response is induced to prevent infection by the diversity of existing serotypes present in pathogenic populations of bacteria. These vaccines that target a too narrow spectrum of serotypes do not offer sufficient prevention of infections, and can also lead to undesirable strain replacements. Here, we examine a novel idea to specifically exploit the narrow spectrum coverage of some vaccines to combat specific, emerging multi- and pan-resistant strains of pathogens. Application of a narrow-spectrum vaccine could serve to prevent infections by some strains that are hard to treat, rather than offer the vaccinated individual protection against infections by the pathogenic species as such. We suggest that vaccines targeted to resistant serotypes have the potential to become important public health tools, and would represent a new approach toward reducing the burden of particular multi-resistant strains occurring in hospitals. Vaccines targeting drug-resistant serotypes would also be the first clinical intervention with the potential to drive the evolution of pathogenic populations toward drug-sensitivity. We illustrate the feasibility of this approach by modeling a hypothetical vaccine that targets a subset of methicillin-resistant Staphylococcus aureus (MRSA) genotypes, in combination with drug treatment targeted at drug-sensitive genotypes. We find that a combined intervention strategy can limit nosocomial outbreaks, even when vaccine efficacy is imperfect. The broader utility of vaccine-based resistance control strategies should be further explored taking into account population structure, and the resistance and transmission patterns of the pathogen considered.
For the diagnosis of seasonal influenza, clinicians rely on point-of-care testing (POCT) using commercially available kits developed against seasonal influenza viruses. However, POCT has not yet been established for the diagnosis of pandemic influenza A virus (H1N1pdm) infection due to the low sensitivity of the existing kits for H1N1pdm.
An immunochromatography (IC) test kit was developed based on a monoclonal antibody against H1N1pdm, which does not cross-react with seasonal influenza A or B viruses. The efficacy of this kit (PDM-IC kit) for the diagnosis of H1N1pdm infection was compared with that of an existing kit for the detection of seasonal influenza viruses (SEA-IC kit). Nasal swabs (n = 542) were obtained from patients with flu-like syndrome at 13 clinics in Osaka, Japan during the winter of 2010/2011. Among the 542 samples, randomly selected 332 were further evaluated for viral presence by reverse transcriptase polymerase chain reaction (RT-PCR). The PDM-IC kit versus the SEA-IC kit showed higher sensitivity to and specificity for H1N1pdm, despite several inconsistencies between the two kits or between the kits and RT-PCR. Consequently, greater numbers of false-negative and false-positive cases were documented when the SEA-IC kit was employed. Significant correlation coefficients for sensitivity, specificity, and negative prediction values between the two kits were observed at individual clinics, indicating that the results could be affected by clinic-related techniques for sampling and kit handling. Importantly, many patients (especially influenza-negative cases) were prescribed anti-influenza drugs that were incongruous with their condition, largely due to physician preference for patient responses to questionnaires and patient symptomology, as opposed to actual viral presence.
Concomitant use of SEA-IC and PDM-IC kits increased the likelihood of correct influenza diagnosis. Increasing the credibility of POCT is anticipated to decrease the inappropriate dispensing of anti-influenza drugs, thereby minimizing the emergence of drug-resistant H1N1pdm strains.
In order to adequately assess the effectiveness of vaccination in helping to control vaccine-preventable infectious disease, it is important to identify the adherence and uptake of risk-based recommendations.
The current project includes data from five consecutive datasets of the National Health and Wellness Survey (NHWS): 2007 through 2011. The NHWS is an annual, Internet-based health questionnaire, administered to a nationwide sample of adults (aged 18 or older) which included items on vaccination history as well as high-risk group status. Vaccination rates and characteristics of vaccinees were reported descriptively. Logistic regressions were conducted to predict vaccination behavior from sociodemographics and risk-related variables.
The influenza vaccination rate for all adults 18 years and older has increased significantly from 28.0% to 36.2% from 2007 to 2011 (ps<.05). Compared with those not at high risk (25.1%), all high-risk groups were vaccinated at a higher rate, from 36.8% (pregnant women) to 69.7% (those with renal/kidney disease); however, considerable variability among high-risk groups was observed. Vaccination rates among high-risk groups for other vaccines varied considerably though all were below 50%, with the exception of immunocompromised respondents (57.5% for the hepatitis B vaccine and 52.5% for the pneumococcal vaccine) and the elderly (50.4% for the pneumococcal). Multiple risk factors were associated with increased rate of vaccination for most vaccines. Significant racial/ethnic differences with influenza, hepatitis, and herpes zoster vaccination rates were also observed (ps<.05).
Rates of influenza vaccination have increased over time. Rates varied by high-risk status, demographics, and vaccine. There was a pattern of modest vaccination rate increases for individuals with multiple risk factors. However, there were relatively low rates of vaccination for most risk-based recommendations and all fell below national goals.
To examine the risk of adverse effects of special interest in persons vaccinated against seasonal influenza compared with unvaccinated persons aged 65 and above.
We retrospectively observed 41,986 vaccinated elderly persons and 50,973 unvaccinated elderly persons in Taiwan from October 1, 2008, through September 30, 2009, using the National Health Insurance database. Neurological and autoimmune disorders and one-year hospitalization rates and in-hospital mortality rates were analyzed according to the vaccination status. Propensity score analysis was used to assess the relationship between adverse outcomes, hospitalization rates, and vaccination status.
45% of the elderly received influenza vaccination. Multiple logistic regression showed that the probability of being vaccinated was related to more patients visiting for URI symptoms (odds ratio (OR), 1.03; 95% CI, 1.02–1.03), men (OR, 1.15; 95% CI, 1.12–1.17), increased age (OR, 1.02; 95% CI, 1.02–1.03), and more comorbidities (OR, 1.2; 95% CI, 1.17–1.23). There were no statistical differences in neurological and autoimmune diseases between the vaccinated and unvaccinated individuals using propensity score analysis, but vaccinated persons had a reduced hospitalization rate of 19% (odds ratio [OR], 0.81; 95% CI, 0.77–0.84) for the first six-months and 13% for one-year of follow-up (OR, 0.87; 95% CI, 0.85–0.9).
Based on data from the one-year follow-ups among 93,049 elderly persons in Taiwan, reassuring results for selected neurological and autoimmune diseases were found among the vaccinated individuals after adjusting other factors. Influenza vaccination decreased the risk for hospitalization. Public health strategies must continue to improve the influenza vaccination rate among the elderly with information based upon tangible evidence.
Disseminated Candida albicans infection results in high morbidity and mortality despite treatment with existing antifungal drugs. Recent studies suggest that modulating the host immune response can improve survival, but specific host targets for accomplishing this goal remain to be identified. The extracellular matrix protein thrombospondin-1 is released at sites of tissue injury and modulates several immune functions, but its role in C. albicans pathogenesis has not been investigated. Here, we show that mice lacking thrombospondin-1 have an advantage in surviving disseminated candidiasis and more efficiently clear the initial colonization from kidneys despite exhibiting fewer infiltrating leukocytes. By examining local and systemic cytokine responses to C. albicans and other standard inflammatory stimuli, we identify a crucial function of phagocytes in this enhanced resistance. Subcutaneous air pouch and systemic candidiasis models demonstrated that endogenous thrombospondin-1 enhances the early innate immune response against C. albicans and promotes activation of inflammatory macrophages (inducible nitric oxide synthase+, IL-6high, TNF-αhigh, IL-10low), release of the chemokines MIP-2, JE, MIP-1α, and RANTES, and CXCR2-driven polymorphonuclear leukocytes recruitment. However, thrombospondin-1 inhibited the phagocytic capacity of inflammatory leukocytes in vivo and in vitro, resulting in increased fungal burden in the kidney and increased mortality in wild type mice. Thus, thrombospondin-1 enhances the pathogenesis of disseminated candidiasis by creating an imbalance in the host immune response that ultimately leads to reduced phagocytic function, impaired fungal clearance, and increased mortality. Conversely, inhibitors of thrombospondin-1 may be useful drugs to improve patient recovery from disseminated candidiasis.
Previous studies suggested that both the frequency and the mean fluorescence intensity (MFI) of cytokine secreting T cells could be of great value for immunogenicity evaluation of a vaccine. In this study, by constructing epitope-based DNA vaccines encoding a previously identified CD8+ T cell epitope, we investigated the influence of multiplying epitope copies on both the frequency and the MFI of specific IFN-γ secreting CD8+ T cells. We found that frequencies of specific CD8+ T cell could be improved by multiplying epitope copies, while the MFI of IFN-γ secreted by epitope-specific CD8+ T cells decreased synchronously. And further analysis showed that the decrease of MFI was not caused by the functional avidity variation of CD8+ T cell receptor.
The ability of Notch signaling to regulate T helper cell development and differentiation has been widely accepted. Fringe, O-fucose-β1,3-N-acetylglucosaminyltransferases modulate Notch receptor expression and promote the Notch signaling pathway through receptor-ligand binding. In this study, we assayed the expression levels of three Fringe homologs in naive CD4+T cells in asthmatic rats. We found that Radical Fringe (Rfng) was highly expressed, whereas both Lunatic Fringe (Lfng) and Manic Fringe (Mfng) were expressed at low levels. Down-regulation of Rfng using siRNA, and overexpression of Lfng or Mfng enhanced Th1 subset lineages and diminished Th2 subset lineages. Notch signaling was more activated in asthmatic naïve CD4+T cells than in control cells, and Lfng, but not Mfng or Rfng, partly inhibited Notch signaling in asthmatic naïve CD4+T lymphocytes. Lfng overexpression resulted in significantly decreased Th2 cytokine production in asthma, which was the same effect as the GSI (γ-secretase inhibitor) treatment alone, but had an increased effect on Th1 cytokines than GSI treatment. Collectively, these data identify the essential role of Fringe modulating naïve CD4+T cells differentiation through Notch signaling. Lfng regulated Th2 cells differentiation via a Notch-dependent manner and Th1 cells differentiation via a Notch-independent manner. Fringe could be a therapeutic strategy for the management and prevention of allergic asthma.
We report the rational design and in vivo testing of mosaic proteins for a polyvalent pan-filoviral vaccine using a computational strategy designed for the Human Immunodeficiency Virus type 1 (HIV-1) but also appropriate for Hepatitis C virus (HCV) and potentially other diverse viruses. Mosaics are sets of artificial recombinant proteins that are based on natural proteins. The recombinants are computationally selected using a genetic algorithm to optimize the coverage of potential cytotoxic T lymphocyte (CTL) epitopes. Because evolutionary history differs markedly between HIV-1 and filoviruses, we devised an adapted computational technique that is effective for sparsely sampled taxa; our first significant result is that the mosaic technique is effective in creating high-quality mosaic filovirus proteins. The resulting coverage of potential epitopes across filovirus species is superior to coverage by any natural variants, including current vaccine strains with demonstrated cross-reactivity. The mosaic cocktails are also robust: mosaics substantially outperformed natural strains when computationally tested against poorly sampled species and more variable genes. Furthermore, in a computational comparison of cross-reactive potential a design constructed prior to the Bundibugyo outbreak performed nearly as well against all species as an updated design that included Bundibugyo. These points suggest that the mosaic designs would be more resilient than natural-variant vaccines against future Ebola outbreaks dominated by novel viral variants. We demonstrate in vivo immunogenicity and protection against a heterologous challenge in a mouse model. This design work delineates the likely requirements and limitations on broadly-protective filoviral CTL vaccines.
In recent years, the prevalence of HIV-1 infection has been rapidly increasing among men who have sex with men (MSM). However, it remains unknown how the host immune system responds to the infection in this population. We assessed the quantity of HIV-specific CD8+ T-cell responses by using Elispot assay and their functionalities by measuring 5 CD8+ T-cell evaluations (IL-2, MIP-1β, CD107a, TNF-α, IFN-γ) with flow cytometry assays among 18 primarily and 37 early chronically HIV-infected MSM. Our results demonstrated that subjects at early chronic phase developed HIV-specific CD8+ T-cell responses with higher magnitudes and more diversified functionalities in comparison with those at primary infection. However, populations with IL-2+ CD107a+ or in combination with other functionality failed to develop in parallel. The multifunctional but not monofunctional HIV-specific CD8+ T cells were associated with higher CD4+ T -cell counts and lower viral loads. These data revealed that prolonged infection from primary to early chronic infection could selectively increase the functionalities of HIV-specific CD8+ T cells in HIV-infected MSM population, the failure to develop IL-2 and cytotoxic functionalities in parallel may explain why the increased HIV-specific CD8+ T cells were unable to enhance the containment of HIV-1 replication at the early chronic stage.
An effective anti-human immunodeficiency virus-1 (HIV-1) microbicide should exert its action in the absence of causing aberrant activation of topical immunity that will increase the risk of HIV acquisition. In the present study, we demonstrated that the vaginal application of cellulose sulfate (CS) gel induced topical mucosal inflammatory responses; the addition of minocycline to CS gel could significantly attenuate the inflammation in a mice model. The combined gel of CS plus minocycline not only reduced the production of inflammatory cytokines in cervicovaginal lavages (CVLs), also down-regulated the activation of CD4+ T cells and the recruitment of other immune cells including HIV target cells into vaginal tissues. Furthermore, an In vitro HIV-1 pseudovirus infection inhibition assay showed that the combined gel decreased the infection efficacy of different subtypes of HIV-1 pseudoviruses compared with that of CS gel alone. These results implicate that minocycline could be integrated into microbicide formulation to suppress the aberrant activation of topical mucosal immunity and enhance the safety profile during the application of microbicides.
Advances in HIV antiretroviral therapy (ART) has reduced mortality in people living with HIV (PLHIV), resulting in an ageing population of PLHIV. Knowledge of demographic details such as age, geographical location and sex, will aid in the planning of training and resource allocation to effectively care for the future complex health needs of PLHIV.
An agent-based, stochastic, geographical model was developed to determine the current and future demographic of PLHIV in Australia. Data and parameters were sourced from Australia's National HIV Registry and peer reviewed literature. Processes that were simulated include progression to AIDS, mortality and internal migration.
The model estimates the mean age of PLHIV in Australia is increasing at a rate of 0.49 years each year. The expected proportion of PLHIV in over 55 years is estimated to increase from 25.3% in 2010 to 44.2% in 2020. Median age is lower in inner-city areas of the capital cities than in rural areas. The areas with the highest prevalence of HIV will continue to be capital cities; however, other areas will have greater percentage growth from 2010 to 2020.
The age of the population of people living with HIV is expected to increase considerably in the future. As the population of PLHIV ages, specialist clinical training and resource provision in the aged care sector will also need to be addressed.
H3N2 influenza viruses have now circulated in the human population for 43 years since the pandemic of 1968, accumulating sequence changes in the hemagglutinin (HA) and neuraminidase (NA) that are believed to be predominantly due to selection for escape from antibodies. Examination of mutations that persist and accumulate led to identification of antigenically significant mutations that are contained in five antigenic sites (A–E) mapped on to the H3 HA. In early H3N2 isolates, antigenic site A appeared to be dominant while in the 1990s site B seemed more important. To obtain experimental evidence for dominance of antigenic sites on modern H3 HAs, we have measured antibodies in plasma of human subjects who received the 2006–07 trivalent subunit influenza vaccine (H3 component A/Wisconsin/67/05) or the 2008–09 formulation (H3 component A/Uruguay/716/07). Plasmas were tested against expressed HA of Wisconsin-like influenza A/Oklahoma/309/06 and site-directed mutants in antigenic site A (NNES121-124ITEG, N126T, N133D, TSSS135-138GSNA, K140I, RSNNS142-146PGSG), and antigenic site B (HL156-157KS, KFK158-160GST, NDQI189-192QEQT, A196V). “Native ELISA” analysis and escape mutant selection with two human monoclonal antibodies demonstrated that antibody E05 binds to antigenic site A and 1_C02 binds to site B. We find that most individuals, after vaccination in seasons 2006–07 and/or 2008–09, showed dominance of antigenic site B recognition over antigenic site A. A minority showed dominance of site A in 2006 but these were reduced in 2008 when the vaccine virus had a site A mutation. A better understanding of immunodominance may allow prediction of future antigenic drift and assist in vaccine strain selection.
Cytotoxic T lymphocyte associated antigen-4 (CTLA-4) is involved in the activation pathways of T lymphocytes. It has been shown that the circulating form of CTLA-4 is elevated in patients with hymenoptera allergy and can be down regulated by immunotherapy.
to assess the effects on CTLA-4 of venom immunotherapy, given with different induction protocols: conventional (6 weeks), rush (3 days) or ultra rush (1 day).
Sera from patients with hymenoptera allergy were collected at baseline and at the end of the induction phase. CTLA-4 and IL-10 were assayed in the same samples. A subset of patients were assayed also after 12 months of VIT maintenance.
Ninety-four patients were studied. Of them, 50 underwent the conventional induction, 20 the rush and 24 the ultra-rush. Soluble CTLA-4 was detectable in all patients at baseline, and significantly decreased at the end of the induction, irrespective of its duration. Of note, a significant decrease of sCTLA-4 could be seen already at 24 hours. In parallel, IL-10 significantly increased at the end of the induction. At 12 months, sCTLA-4 remained low, whereas IL-10 returned to the baseline values.
Serum CTLA4 is an early marker of the immunological effects of venom immunotherapy, and its changes persist after one year of maintenance treatment.