Single-dose replicating poxvirus vector-based RBD vaccine drives robust humoral and T cell immune response against SARS-CoV-2 infection

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Hepatitis B and circadian rhythm of the liver

The circadian rhythm in humans is determined by the central clock located in the hypothalamus’s suprachiasmatic nucleus, and it synchronizes the peripheral clocks in other tissues. Circadian clock genes and clock-controlled genes exist in almost all cell types. They have an essential role in many physiological processes, including lipid metabolism in the liver, regulation of the immune system, and the severity of infections. In addition, circadian rhythm genes can stimulate the immune response of host cells to virus infection. Hepatitis B virus (HBV) infection is the leading cause of liver disease and liver cancer globally. HBV infection depends on the host cell, and hepatocyte circadian rhythm genes are associated with HBV replication, survival, and spread. The core circadian rhythm proteins, REV-ERB and brain and muscle ARNTL-like protein 1, have a crucial role in HBV replication in hepatocytes. In addition to influencing the virus’s life cycle, the circadian rhythm also affects the pharmacokinetics and efficacy of antiviral vaccines. Therefore, it is vital to apply antiviral therapy at the appropriate time of day to reduce toxicity and improve the effectiveness of antiviral treatment. For these reasons, understanding the role of the circadian rhythm in the regulation of HBV infection and host responses to the virus provides us with a new perspective of the interplay of the circadian rhythm and anti-HBV therapy. Therefore, this review emphasizes the importance of the circadian rhythm in HBV infection and the optimization of antiviral treatment based on the circadian rhythm-dependent immune response.     

基于微流控核酸等温扩增的 登革病毒现场快速检测技术研究

[摘要]?目的?结合环介导等温扩增技术（loop-mediated isothermal amplification, LAMP）和微流控芯片技术，建立一种适合现场快速检测登革病毒的方法。方法?利用RT-LAMP，针对登革病毒基因组中3’非编码区中特异性序列进行扩增，建立基于微流控芯片技术的LAMP检测方法，优化检测体系，并对该方法的灵敏性和特异性进行评估。结果?基于LAMP 和微流控芯片技术的登革病毒检测方法，通过对病毒模板进行扩增，发现与其他病毒无交叉反应，特异性良好；同时，结果显示该方法对登革病毒检测灵敏性可达61.2 pg/μl，与实时荧光定量PCR仪所达到的检测灵敏性一致。结论?基于LAMP和微流控芯片技术的登革病毒检测方法具有操作简单、快速、对设备要求低等优势,并且灵敏性、特异性均较好，是一种便于开展现场快速检测的方法。     

A candidate multi-epitope vaccine against porcine reproductive and respiratory syndrome virus and Mycoplasma hyopneumoniae induces robust humoral and cellular response in mice

Porcine reproductive and respiratory syndrome virus (PRRSV) and Mycoplasma hyopneumoniae (M. hyopneumoniae, Mhp) are two of the most common pathogens involved in the porcine respiratory disease complex (PRDC) resulting in significant economic losses worldwide. Vaccination is the most effective approach to disease prevention. Since PRRSV and Mhp co-infections are very common, an efficient dual vaccine against these pathogens is required for the global swine industry. Compared with traditional vaccines, multi-epitope vaccines have several advantages, they are comparatively easy to produce and construct, are chemically stable, and do not have an infectious potential. In this study, to develop a safe and effective vaccine, B cell and T cell epitopes of PRRSV-GP5, PRRSV-M, Mhp-P46, and Mhp-P65 protein had been screened to construct a recombinant epitope protein rEP-PM that has good hydrophilicity, strong antigenicity, and high surface accessibility, and each epitope is independent and complete. After immunization in mice, rEP-PM could induce the production of high levels of antibodies, and it had good immunoreactivity with anti-rEP-PM, anti-PRRSV, and anti-Mhp antibodies. The anti-rEP-PM antibody specifically recognizes proteins from PRRSV and Mhp. Moreover, rEP-PM induced a Th1-dominant cellular immune response in mice. Our results showed that the rEP-PM protein could be a potential candidate for the development of a safe and effective multi-epitope peptide combined vaccine to control PRRSV and Mhp infections.     

Variability in non-core vaccination rates of dogs and cats in veterinary clinics across the United States

Vaccination guidelines for dogs and cats indicate that core vaccines (for dogs, rabies, distemper, adenovirus, parvovirus; for cats, feline parvovirus, herpes virus-1, calicivirus) are essential to maintain health, and that non-core vaccines be administered according to a clinician’s assessment of a pet’s risk of exposure and susceptibility to infection. A reliance on individual risk assessment introduces the potential for between-practice inconsistencies in non-core vaccine recommendations. A study was initiated to determine non-core vaccination rates of dogs (Leptospira, Borrelia burgdorferi, Bordetella bronchiseptica, canine influenza virus) and cats (feline leukemia virus) in patients current for core vaccines in veterinary practices across the United States. Transactional data for 5,531,866 dogs (1,670 practices) and 1,914,373 cats (1,661 practices) were retrieved from practice management systems for the period November 1, 2016 through January 1, 2020, deidentified and normalized. Non-core vaccination status was evaluated in 2,798,875 dogs and 788,772 cats that were core-vaccine current. Nationally, median clinic vaccination rates for dogs were highest for leptospirosis (70.5%) and B. bronchiseptica (68.7%), and much lower for canine influenza (4.8%). In Lyme-endemic states, the median clinic borreliosis vaccination rate was 51.8%. Feline leukemia median clinic vaccination rates were low for adult cats (34.6%) and for kittens and 1-year old cats (36.8%). Individual clinic vaccination rates ranged from 0 to 100% for leptospirosis, B. bronchiseptica and feline leukemia, 0–96% for canine influenza, and 0–94% for borreliosis. Wide variation in non-core vaccination rates between clinics in similar geographies indicates that factors other than disease risk are driving the use of non-core vaccines in pet dogs and cats, highlighting a need for veterinary practices to address gaps in patient protection. Failure to implement effective non-core vaccination strategies leaves susceptible dogs and cats unprotected against vaccine-preventable diseases.     

内脏利什曼病合并HIV感染患者诊断和治疗研究进展

内脏利什曼病是全球被忽视的传染病之一,危害严重。而利什曼原虫-人类免疫缺陷病毒(human immunodeficiency virus,HIV)合并感染对流行地区造成的威胁更甚。利什曼原虫与HIV存在相互作用,合并感染者在临床表现、诊断及治疗方面具有一定特殊性,其病死率及复发率均高于HIV阴性的内脏利什曼病患者。本文对利什曼原虫-HIV合并感染患者的临床表现、诊断和治疗进展进行综述。     

乙肝孕妇血清标志物模式与HBV-DNA载量及肝功能关系研究

目的探讨乙肝孕妇血清标志物模式、HBV-DNA载量及肝功能三者之间的关系,为孕期乙肝病毒感染情况的监控和乙肝病毒母婴传播的预防提供参考。方法选取2019年1月-11月在我院产检的767例乙肝表面抗原阳性孕妇的乙肝血清标志物模式、肝功能指标的丙氨酸氨基转移酶(alamine aminotransferase,ALT)及HBVDNA载量进行研究,探讨三者间的关系。结果HBsAg、HBeAg、HBcAb阳性组孕妇HBV-DNA阳性率及病毒载量均高于其余两组(P<0.05);ALT升高程度与HBV-DNA载量具有一定相关性(r=0.255,χ^2=80.150,P=0.000);HBeAg阳性组和HBeAg阴性组间HBV-DNA阳性率、ALT异常率差异均有统计学意义。结论HBV-M、HBV-DNA与肝功能之间有一定的相关性,大三阳孕妇中高病毒载量比例高,应加强乙肝孕妇孕期各项指标的监测,必要时进行干预治疗。     

广西防城港市2017年活禽市场环境样本禽流感监测

目的 了解防城港市活禽市场环境禽流感病毒监测情况,为科学评判疫情并采取适当的防控措施提供理论依据。方法 2017年3—4月在全市活禽市场外环境采集笼具擦物、冼禽污水、禽粪、砧板擦物、禽类饮用水等标本,用荧光定量PCR法检测禽流感病毒FluA、H5、H9、H7核酸,并进行统计学分析。结果 采集全市36个活禽市场外环境标本1 855份,阳性393份,阳性率为21.19%,其中H5阳性28份,H7阳性2份,H9阳性198份,H5和H9混合阳性37份,其他亚型（FluA阳性,H5、H7、H9 阴性）128份;不同地区标本阳性率差异有统计学意义（P<0.05）;城区和乡镇市场采集的标本的阳性率差异无统计学意义。5种类型的标本中,洗禽污水的阳性率最高,其次是砧板擦物, 再次是禽类饮用水和笼具擦物,禽粪的阳性率最低,差异有统计学意义（P<0.05）。结论 防城港市活禽市场环境普遍存在高致病性禽流感病毒的污染,H9亚型是主要的病原体,采取了综合防控措施后,防城港市没有发生人间禽流感疫情。     

The emergence of human Powassan virus infection in North America

Powassan virus (POWV) is a tickborne flavivirus discovered in Ontario, Canada in 1958 that causes long-term neurological sequelae in about half the reported cases and death in a little more than 10 % of cases. The incidence of POWV disease is rising in the United States but there is limited understanding of the scope and causes of recent changes in POWV epidemiology. We focus on quantifying the increase in human POWV disease incidence and infection prevalence in the United States. We also examine differences in the frequency of symptomatic cases and asymptomatic or mildly symptomatic cases, as well as limitations in national and state surveillance for POWV infection. We searched SCOPUS for all articles containing original POWV prevalence research, case studies, or literature reviews published in English. Case studies were supplemented by Morbidity and Mortality Weekly Report POWV data from the Centers for Disease Control and Prevention (CDC) and surveillance information from state health department websites. An increase in the number of POWV cases has been reported in the United States over the past 50 yr, and the geographic range of human POWV cases has expanded. The age distribution of symptomatic POWV cases has shifted, with significantly more individuals over 40 yr old being diagnosed after 1998. The emergence of POWV is due in large part to: (i) a change in transmission of POWV from a vector that rarely bites people (Ixodes cookei) to a new vector that often bites people (Ixodes scapularis) and has expanded its geographic range, (ii) enhanced surveillance efforts for arboviruses, and (iii) a greater awareness of POWV infection.     

The respiratory syncytial virus fusion protein-specific B cell receptor repertoire reshaped by post-fusion subunit vaccination

Respiratory syncytial virus (RSV) is the major cause of acute lower respiratory illness in children of less than 5 years of age which usually results in hospitalization or even in death. Vaccine development is hampered in consequence of a failed vaccine trial with fatalities in the 1960s. Even though research has been more focused on the RSV fusion protein in its pre-fusion conformation, maternal vaccination with post-fusion protein (post F) was considered as a promising vaccine strategy for passive immunization of babies, because post F preserves very potent neutralizing epitopes. We extensively analyzed post F-binding B cell receptor (BCR) repertoires of three vaccinees who received a post F-subunit vaccine in the context of a first-in-human, Phase 1, randomized, observer-blind, placebo-controlled clinical trial (ClinicalTrials.gov Identifier: NCT02298179). In order to compare the vaccine-induced BCR repertoires with BCR repertoires induced by natural infection, we also analyzed pre F- and post F-binding BCRs isolated from a healthy blood donor with relatively high F-binding memory B cell (MBC) frequencies. Analysis of the vaccine-induced repertoires revealed that preferentially V_H4-encoded BCRs were expanded in response to vaccination. Estimation of antigen-driven selection further demonstrated that expanded BCRs accumulated positively selected replacement mutations which substantiated the hypothesis that post F-vaccination induces diversification of V_H4-encoded BCRs in germinal centers. Comparison of the vaccine-induced BCR repertoires with clonally related pre and post F-binding BCRs of the healthy blood donor suggested that the vaccine expanded pre/post F cross-reactive MBCs. Interestingly, several vaccine-induced BCRs shared stereotypic VDJ gene junctions with known neutralizing Abs. Once expressed for functional characterization, the selected monoclonal Abs demonstrated the predicted neutralization activities in plaque reduction neutralization assays indicating that the post F-vaccine induced expansion of neutralizing BCRs.