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1.
Since 1814,when rubella was first described,the origins of the disease and its causative agent,rubella virus(Matonaviridae:Rubivirus),have remained unclear1.Here we describe ruhugu virus and rustrela virus in Africa and Europe,respectively,which are,to our knowledge,the first known relatives of rubella virus.Ruhugu virus,which is the closest relative of rubella virus,was found in apparently healthy cyclops leaf-nosed bats(Hipposideros cyclops)in Uganda.Rustrela virus,which is an outgroup to the clade that comprises rubella and ruhugu viruses,was found in acutely encephalitic placental and marsupial animals at a zoo in Germany and in wild yellow-necked field mice(Apodemus flavicollis)at and near the zoo.Ruhugu and rustrela viruses share an identical genomic architecture with rubella virus2,3.  相似文献   

2.
The first appearance of lipid rafts, or lipid rafts-like structure, was occasionally observed by cryo-electronic microscopy in 1980s as cavity, such as caveolae. However, the fully understanding of lipid raft was attributed by the studies of T cell activation, virus entry/budding, and other membrane events. During the interaction of T cell and antigen presenting cell, a highly organized structure is formed at the interface of the two cells, where cholesterol and sphingolipids are enriched, and form a liquid ordered phase that facilitates the signaling proteins on and off. Lipid rafts are also involved in virus entry and assembly. In this review, we will discuss cholesterolsphingolipid floating microdomain, the lipid raft as a unique compartment of the plasma membrane, with biological functions that ensure correct intracellular traffic of proteins and lipids, such as protein-protein interactions by concentrating certain proteins in these microdomains, while excluding others. We also discuss the disruption of lipid rafts is related to different diseases and aging, and we especially exploit the lipid rafts as pharmaceutical targets for anti-virus and anti-inflammation, particularly a new approach to control HIV infection for AIDS prevention and protection by inhibition or disruption of lipid rafts. Cellular & Molecular Immunology.  相似文献   

3.
Protein ubiquitination is essential for diverse cellular functions including spermatogenesis.The tripartite motif(TRIM)family proteins,most of which have E3 ubiquitin ligase activity,are highly conserved in mammals.They are involved in important cellular processes such as embryonic development,immunity,and fertility.Our previous studies indicated that Trim69,a testis-specific expressed TRIM family gene,potentially participates in the spermatogenesis by mediating testicular cells apoptosis.In this study,we investigated the biological functions of Trim69 in male mice by established Trim69 knockout mice with CRISPR/Cas9 genomic editing technology.Here,we reported that the male Trim69 knockout mice had normal fertility.The adult knockout mice have shown that the appearance of testes,testis/body weight ratios,testicular histomorphology,and the number and quality of sperm were consistent with wild-type mice.These results indicated that the E3 ubiquitin ligase protein Trim69 was not essential for male mouse fertility,and it might be compensated by other TRIM family members such as Trim58 in Trim69-deficiency testis.This study would help to elucidate the functions of tripartite motif protein family and the regulation of spermatogenesis.  相似文献   

4.
Many B cell epitopes within p24 of human immunodeficiency virus type 1 (HIV-1) were identified, while most of them were determined by using murine monoclonal antibodies reacting with overlapping peptides of p24. Therefore these epitopes may not represent the actual epitopes recognized by the HIV-1 infected individuals. In the present study, immune responses of 67 HIV-1 positive sera from Yunnan Province, China to five peptides on p24 of HIV-1 and one of HIV-2 were analyzed. All of 67 sera did not recognize peptide GA-12 on HIV-1 and peptide AG-23 on HIV-2, which indicated that GA-12 was not human B cell epitope and AG-23 did not cross-react with HIV-1 positive serum. Except 13 sera (19.4%), all remaining sera did not recognize peptides NI-15, DR-16, DC-22 and PS-18, which indicated that these four peptides represented B cell linear epitopes of HIV-1 p24 in some HIV-1 infected individuals but not the immuno-dominant epitopes in most individuals.  相似文献   

5.
Objective To investigate the evolution of HIV-1 envelope (env) gene from the individuals infected by the virus from one donor, the entry mediated by the envelope glycoprotein and the variation in the main neutralizing epitopes of envelope. Methods The genetic distances of the HIV-1 envelope genes derived from previous studies were analyzed. A series of envelope-pseudotyped viruses were constructed by co-transfecting HEK293T cells with a HIV-1 plasmid bearing the firefly luciferase reporter gene and an envelope expression plasmid. The entry ability of the envelope-pseudotyped viruses into U87. CD4. CCR5 or U87. CD4. CXCR4 cell lines was examined. The ami-no acid sequences representing the epitopes to the broad-neutralizing antibodies within the envelope glycoproteins were also investigated. Results It was found that the genetic distance of the 24 env genes with complete open reading frame was (7.91 ±0.78)% towards HIV-1 CNHN24, and (6.90 ±0.79)% towards RL42. Among the variable regions, the genetic distance of V1/V2 showed the biggest distance, and that of V3 showed the smallest distance. There were CCR5-tropic, CXCR4-tropic and CCR5/CXCR4-dual-tropic Env-pseudoviruses. Furthermore, in these envelopes, the epitopes to IgG1 b12 2F5 and 4E10 antibody were conserved, while the epitope to 447-52D was variable. Conclusion There is definite env gene variation among the viruses derived from the same donor. The variation influences the entry ability and tropism of emelope pseudoviruses. The epitopes to the main broad-neutralizing antibodies are conserved.  相似文献   

6.
Embryos express paternal antigens that are foreign to the mother, but the mother provides a special immune milieu at the fetal-maternal interface to permit rather than reject the embryo growth in the uterus until parturition by establishing precise crosstalk between the mother and the fetus. There are unanswered questions in the maintenance of pregnancy, including the poorly understood phenomenon of maternal tolerance to the allogeneic conceptus, and the remarkable biological roles of placental trophoblasts that invade the uterine wall. Chemokines are multifunctional molecules initially described as having a role in leukocyte trafficking and later found to participate in developmental processes such as differentiation and directed migration. It is increasingly evident that the gestational uterine microenvironment is characterized, at least in part, by the differential expression and secretion of chemokines that induce selective trafficking of leukocyte subsets to the maternal-fetal interface and regulate multiple events that are closely associated with normal pregnancy. Here, we review the expression and function of chemokines and their receptors at the maternal-fetal interface, with a special focus on chemokine as a key component in trophoblast invasiveness and placental angiogenesis, recruitment and instruction of immune cells so as to form a fetus-supporting milieu during pregnancy. The chemokine network is also involved in pregnancy complications.  相似文献   

7.
Objective To investigate the evolution of HIV-1 envelope (env) gene from the individuals infected by the virus from one donor, the entry mediated by the envelope glycoprotein and the variation in the main neutralizing epitopes of envelope. Methods The genetic distances of the HIV-1 envelope genes derived from previous studies were analyzed. A series of envelope-pseudotyped viruses were constructed by co-transfecting HEK293T cells with a HIV-1 plasmid bearing the firefly luciferase reporter gene and an envelope expression plasmid. The entry ability of the envelope-pseudotyped viruses into U87. CD4. CCR5 or U87. CD4. CXCR4 cell lines was examined. The ami-no acid sequences representing the epitopes to the broad-neutralizing antibodies within the envelope glycoproteins were also investigated. Results It was found that the genetic distance of the 24 env genes with complete open reading frame was (7.91 ±0.78)% towards HIV-1 CNHN24, and (6.90 ±0.79)% towards RL42. Among the variable regions, the genetic distance of V1/V2 showed the biggest distance, and that of V3 showed the smallest distance. There were CCR5-tropic, CXCR4-tropic and CCR5/CXCR4-dual-tropic Env-pseudoviruses. Furthermore, in these envelopes, the epitopes to IgG1 b12 2F5 and 4E10 antibody were conserved, while the epitope to 447-52D was variable. Conclusion There is definite env gene variation among the viruses derived from the same donor. The variation influences the entry ability and tropism of emelope pseudoviruses. The epitopes to the main broad-neutralizing antibodies are conserved.  相似文献   

8.
To investigate the phenotypic knockout of HIV-1 chemokine coreceptor CXCR4 and CCR5 by intrakines and its inhibitory effect on HIV-1 infection. Primary human PBLs were transduced with the recombinant vector pLNCX-R-K-S-K(△NGFR), followed by anti-NGFR/anti-IgG-magnetic bead method selection and FCM detection. The transduced PBLs were infected with DP1 HIV-1 virus thereafter envelope-mediated syncytium formation and p24 detection were carried out to study the blockage of HIV-1 infection by co-inactivation of CCR5 and CXCR4. pLNCX-R-K-S-K (△NGFR)-transduced PBILs were isolated with an anti-NGFR/anti-IgG-magnetic bead method. After isolation, about 70% of the PBLs were positive for the NGFR marker. When the transduced PBLs were infected with DP1 HIV-1 virus, envelop-mediated syncytium formation was almost completely inhibited by pLNCX-R-K-S-K(△NGFR) transfection. Also, p24 antigen was very low in the cultures of pLNCX-R-K-S-K (△NGFR) transduced PBLs. pLNCX-R-K-S-K(△NGFR) transduction inhibited the production of DP1 p24 antigen by 15%, 43% and 19% on days 4, 7 and 10 respectively. The lymphocytes with the phenotypic knockout of CCR5 and CXCR4 could protect primary human PBLs from DP1 HIV-1 virus infection.  相似文献   

9.
In recent years, our understanding of how the immune system interacts with the developing fetus and placenta has greatly expanded. There are many laboratories that provide tests for diagnosis of pregnancy outcome in women who have recurrent pregnancy loss (RPL) or pre-eclampsia. These tests are based on the premise that immune response to the fetus is equivalent to the adaptive immune response to a transplant. New understanding leads to the concept that the activated innate response is vital for pregnancy and this can result in more effective testing and treatment to prevent an abnormal pregnancy in the future. We describe here only three such areas for future testing: one area involves sperm and semen and factors necessary for successful fertilization; another area would determine conditions for production of growth factors necessary for implantation in the uterus; finally, the last area would be to determine conditions necessary for the vascularization of the placenta and growing fetus by activated natural killer (NK) cells (combinations of killer cell immunoglobulin-like receptor (KIR) family genes with HLA-C haplotypes) that lead to capability of secreting angiogenic growth factors. These areas are novel but understanding their role in pregnancy can lead to insight into how to maintain and treat pregnancies with complicating factors.  相似文献   

10.
11.
12.
L-ficolin, one of lectin families, is a recently identified complement factor that initiates lectin pathway of complement. Little is known about its role in viral hepatitis. In the present study, we found that L-ficolin in serum from 103 patients with hepatitis C virus (HCV), were significantly higher than that in 150 healthy controls. We further found that L-ficolin expressions were significantly increased in vitro study by HCV JFH-1 infected human hepatocyte cell line Huh7.5.1. Investigation of the mechanisms of the L-ficolin action on HCV demonstrated that L-ficolin protein could recognize and bind to envelope glycoproteins E1 and E2 of HCV, activating the lectin complement pathway-mediated cytolytic activity in HCV-infected hepatocyte. This interaction between L-ficolin and HCV E1 and E2 glycoproteins was attributed to the N-glycans of E1 and E2. These findings provide new insights into the biological functions of L-ficolin in clinically important hepatic viral diseases.  相似文献   

13.
T cells modified with chimeric antigen receptor are an attractive strategy to treat Epstein-Barr virus(EBV) associated malignancies.The EBV latent membrane protein 1(LMP1) is a 66-KD integral membrane protein encoded by EBV that consists of transmembrane-spanning loops.Previously,we have identified a functional signal chain variable fragment(scFv) that specifically recognizes LMP1 through phage library screening.Here,we constructed a LMP1 specific chimeric antigen receptor containing anti-LMP1 scFv,the CD28 signalling domain,and the CD3ζchain(HELA/CAR).We tested its functional ability to target LMP1 positive nasopharyngeal carcinoma cells.HELA/CAR cells were efficiently generated using lentivirus vector encoding the LMP1-specific chimeric antigen receptor to infect activated human CD3+ T cells.The HELA/CAR T cells displayed LMP1 specific cytolytic action and produced IFN-γ and IL-2 in response to nasopharyngeal carcinoma cells overexpressing LMP1.To demonstrate in vivo anti-tumor activity,we tested the HELA/CAR T cells in a xenograft model using an LMP1 overexpressing tumor.Intratumoral injection of anti-LMP1 HELA/CAR-T cells significantly reduced tumor growth in vivo.These results show that targeting LMP1 using HELA/CAR cells could represent an alternative therapeutic approach for patients with EBV-positive cancers.  相似文献   

14.
15.
In this study,we hypothesized that Piezo 1 channels mediate the compression-enhanced invasive phenotype of cancer cells via a caveolae-dependent mechanism.To test this hypothesis,we examined in vitro cultured human breast cancer cells for their ability to invade and degrade extracellular matrix in the presence or absence of compressive stress,together with corresponding changes in Piezo1 as well as cytoskeletal remodeling and calcium signaling.Here we show that compressive stress enhanced invasion,matrix degradation,and invadopodia formation of breast cancer cells.We further identified Piezo1 as the putative mechanosensitive cellular component that transmits compression to induce calcium influx,which in turn triggers several downstream pathways.Interestingly,for the first time we observed inv-adopodia with matrix degradation ability on the apical side of the cells, similar to those commonly observed at the cell s ventral side.Furthermore,we demonstrate that Piezo1 and caveolae were both involved in mediating the compressive stress-induced cancer cell invasive phenotype as Piezo 1 and caveolae were often colocalized,and reduction of Cav-1 expression or disruption of caveolae with methyl-β-cyclodextrin led to not only reduced Piezo1 expression but also attenuation of the invasive phenotypes promoted by compressive stress.Taken together,we first observed that in breast cancer cells,simulating uncontrolled growth-induced compressive stress enhanced cancer cell invasion,matrix degradation,and invadopodia and stress fiber formation.Our study also confirmed that Piezo1 channels are highly expressed in breast cancer cells compared to normal breast cells,and is consistent with the data that compressive stress regulates cell migration of breast cancer cells but not normal breast cells.Additionally,we identified that Piezol mediated these processes and the invasive phenotypes also depended on the integrity of caveolae.These findings provide the first demonstration that compressive stress enhances matrix degradation by breast cancer cells and Piezo1 is an essential mechanosensor and transducer for such stress in breast cancer.Additionally,our data supports the model where caveolae might be the"mechanical force foci"which concentrates Piezol to facilitate force sensing and transduction in mammalian cells.Our work may have relevance to human tumors in vivo.As solid tumor experiences high compressive stress due to uncontrolled proliferation and confinement by the stiff extracellular matrix environment,this microenvironment facilitates compression-enhanced cell invasion.The identification of Piezo1's crucial role in this process provides the first demonstration of the dependence of Piezo1 channels on the response of breast cancer cells to physiological compressive stress.The functional dependence of Piezo1 on caveolae further highlights the importance of membrane organization and composition on forcegated ion channels.Both of these findings underscore the cardinal role that Piezo1 channels play in regulating cell invasion and may inspire further development targeting Piezol as a potential cancer therapeutic target.  相似文献   

16.
The dengue viruses (DEN, genus Flavivirus, family Flaviviridae) are mosquito borne and have caused 100 million cases of dengue fever each year in most tropical and subtropical areas of the world. However, in the Southwest area of Yunnan-Guizhou Plateau, China, the previous work demonstrated that different geographic strains of Aedes albopictus were susceptible to dengue virus. In this study, we collected 456 sera samples from patients with fever and 994 sera samples from healthy population in Dushan and Xingyi area of Yunnan-Guizhou Plateau, China. All sera samples were tested for dengue IgG by enzyme-linked immunosorbent assay (ELISA). Patients' sera samples were tested for dengue IgM and DEN antigen was checked in the sera of 6 from 456 samples with which C6/36 cell in culated by IFA. The results indicate that these patients with fever were infected with DEN-2 and suggest that DEN infection had existed in Dushan and Xingyi area of Yunnan-Guizhou Plateau, China.  相似文献   

17.
Integrase has become an attractive target for the design of anti-HIV inhibitor because it plays a quite important role in the process of HIV-1 virus replication. The quinoline ring derivatives, which have the similar pharmacophore toβ-diketoacids, are the kind of integrase inhibitor with highly antiviral activity. A series of quinoline ring derivatives were analyzed by the comparative molecular field analysis(Co MFA), comparative molecular similarity induces analysis(Co MSIA) and Topomer Co MFA methods. Firstly, we chose 77 compounds from former papers as a dataset,followed by dividing it into the training set and test set randomly. Then, we constructed predictive models of Co MFA, Co MSIA and Topomer Co MFA, respectively. The Co MFA yielded the best cross-validated model with a q2=0.758, non-cross-validated r2=0.988.The Co MSIA model yielded a q2=0.701 and r2=0.986 while the Topomer Co MFA model has q2=0.661 and r2=0.966. Through verification, these results suggested a strong predictive ability to the design of novel highly active HIV-1 integrase inhibitors for therapy.  相似文献   

18.
In a new step forward in artificial heart technology, French medical company has developed a new artificial heart that is part bovine and part machine. The idea behind this design was to use actual bovine tissue for parts of the artificial heart that would come in contact with a wearer's blood, thus leading to greater biocompatibility. Their design consists of two chambers separated by a membrane taken from a cow's heart. One chamber houses the wearer's actual blood and the other chamber houses hydraulic fluid that is driven by a motor to exert force on the membrane, thereby causing flow in the chamber housing blood, leading to circulation. In addition to the dividing membrane being made of bovine tissue, the heart valves are also made of components taken from cows. The bovine components used to make the valve not only serves the purpose of greater biocompatibility, but is also equipped with embedded sensors to measure the pressure on them. Such measurements could be used to monitor exertion and adiust "hear rate" as needed.  相似文献   

19.
Type I interferons are critical antiviral cytokines produced following herpes simplex virus type-1 (HSV-1) infection that act to inhibit viral spread.In the present study,we identify HSV-infected and adjacent uninfected corneal epithelial cells as the source of interferon-α.We also report mice deficient in the A1 chain of the type I IFN receptor (CD118-/) are extremely sensitive to ocular infection with low doses (100 PFU) of HSV-1 as seen by significantly elevated viral titers in the cornea compared to wild type (WT) controls.The enhanced susceptibility correlated with a loss of CD4 + and CD8 + T cell recruitment and aberrant chemokine production in the cornea despite mounting an adaptive immune response in the draining mandibular lymph node of CD118-/mice.Taken together,these results highlight the importance of IFN production in both the innate immune response as well as eliciting chemokine production required to facilitate adaptive immune cell trafficking.  相似文献   

20.
The class A scavenger receptor,encoded by the macrophage scavenger receptor 1(MSR1) gene,is a pattern recognition receptor(PPR) primarily expressed in macrophages.It has been reported that genetic polymorphisms of MSR1 are significantly associated with the number of diseased vessels and coronary artery narrowing greater than 20% in Caucasians.However,whether it links genetically to coronary artery disease(CAD) in Chinese is not defined.Here,we performed an independent case-control study in a Chinese population consisting of 402 CAD cases and 400 controls by genotyping ten single nucleotide polymorphisms(SNPs) of MSR1.We found that rs416748 and rs13306541 were significantly associated with an increased risk of CAD with per allele odds ratio(OR) of 1.56 [95% confidence interval(CI) = 1.28-1.90;P < 0.001] and 1.70(95% CI = 1.27-2.27;P < 0.001),respectively.Our results indicate that genetic variants of MSR1 may serve as predictive markers for the risk of CAD in combination with traditional risk factors of CAD in Chinese population.  相似文献   

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