Hla-Bb, Dr3 T Cell Impairhent is Completely Restored by in Vitho Treatment with Interleukin-2

The activity of recombinant interleukin-2 (rIL-2) on the in vitro lymphocyte proliferative response to phytohemagglutinin mitogen was investigated in healthy HLA-BB, DR3 positive and negative subjects. the response to mitogen, significantly decreased in HLA-BB, DR3 positive subjects, was completely restored by adding rIL-2. Moreover, in HLA-BB, DR3 positive subjects the in vitro treatment with rIL-2 significantly increased the reduced frequency of mitogen responsive T lymphocyte precursors, as assessed by limiting dilution analysis. These data suggest that a decrease in the size of the pool of T cell precursors able to produce IL-2 is responsible for the impairment of T cell function observed in HLA-BB, DR3 positive subjects. Since in autoimmune diseases it is possible to show the same impairment(s) of T cell functions which can be observed in HLA-BB, DRB positive subjects, these results could be of practical value for the understanding of pathogenetic mechanismts) of autoimmune diseases and, in case, for therapeutical purposes.     

False-Positive IgM Antibody Tests for Cytomegalovirus in Patients with Acute Epstein-Barr Virus Infection

 The diagnosis of acute cytomegalovirus (CMV) infection is frequently based on a positive IgM result. False-positive reactions due to interfering infections may exist. Between August 1998 and May 1999, 62 patients were found to be IgM positive and IgG negative with the Axsym assay (Abbott, Germany). Serological testing for Epstein-Barr virus (EBV) was performed in these patients to detect any cross-reactivity due to acute mononucleosis. Additionally, the results of the CMV Axsym was evaluated in 40 patients with acute EBV infection. The results suggest that the CMV-IgM Axsym assay shows a lack of specificity due to acute EBV infection. Precautions must be taken when CMV-IgM Axsym results are interpreted. It seems necessary to confirm equivocal results with another technique and to take into account other clinical and biological observations.     

Neutralizing Antibody Response of Guinea Pigs to Lymphocytic Choriomeningitis Virus

A 24-h neutralization test that is based on fluorescent cell counting was used for the detection and quantitative determination of serum-neutralizing antibody against lymphocytic choriomeningitis virus. The earliest manifestation of serum-neutralizing antibody in guinea pigs was shown to occur within 1 week after inoculation with lymphocytic choriomeningitis virus. Within 11 weeks, serum-neutralizing antibody increased from 20- to 300-fold. Neutralizing end points of serum samples, obtained from 3 through 11 weeks, were enhanced as much as sevenfold by complement. Anti-guinea pig immunoglobulin G or anti-whole guinea pig serum potentiated the neutralizing activity of serum as much as 20- and 40-fold, respectively.     

Guinea Pig Herpes-Like Virus Infections II. Antibody Response and Virus Persistence in Mice and Rabbits

Mice inoculated with guinea pig herpes-like virus produced minimal, if any, antibody response, and no virus was isolated from the inoculated animals 64 days after administration. The antibody response in rabbits inoculated with the same virus was prompt and reached a high level within 14 to 29 days regardless of the site of inoculation. Long-term persistence of viremia was observed only in intravenously inoculated rabbits; a brief period of viremia was observed in intraperitoneally inoculated rabbits, but no viremia was obtained in rabbits inoculated by the subcutaneous route. Maternal antibody was transferred readily to offspring; however, transference of infectious virus from mother to offspring was demonstrable in only one of 75 fetuses tested.     

IgA Antibody Response of Swine to Foot-and-Mouth Disease Virus Infection and Vaccination

Foot-and-mouth disease virus (FMDV) continues to be a significant economic problem worldwide. Control of the disease involves the use of killed-virus vaccines, a control measure developed decades ago. After natural infection, the primary site of replication of FMDV is the pharyngeal area, suggesting that a mucosal immune response is the most effective. Humoral immunity to killed-virus vaccination induces antibodies that can prevent the clinical disease but not local infection. Determining whether infection or vaccination stimulates IgA-mediated local immunity depends on the method of analysis. Different assays have been described to analyze the quality of antibody responses of cattle and swine to FMDV, including indirect double-antibody sandwich enzyme-linked immunosorbent assay (IDAS-ELISA) and antibody capture assay-ELISA (ACA-ELISA). We tested these assays on swine and show that vaccinated animals had FMDV-specific IgM and IgG but no IgA in either serum or saliva. After the infection, both assays detected FMDV-specific IgM, IgG, and IgA in serum. Notably, serum IgA was more readily detected using the ACA-ELISA, whereas IgA was not detected in saliva with this assay. FMDV-specific IgA antibodies were detected in saliva samples using the IDAS-ELISA. These data show that parenterally administered, killed-virus vaccine does not induce a mucosal antibody response to FMDV and illuminates limitations and appropriate applications of the two ELISAs used to measure FMDV-specific responses. Further, the presence of the IgA antivirus in serum correlates with the presence of such antibodies in saliva.Foot-and-mouth disease virus (FMDV) continues to be a significant economic problem worldwide. In FMDV-free countries, an outbreak of the virus freezes the export of all animal products, causing significant loss of revenue to the livestock industry. Eradication of the disease from areas of endemicity involves the use of killed-virus vaccines, a control measure developed decades ago. The vaccine offers clinical protection against FMDV, but it does not prevent virus excretion or the establishment of latency after challenge infection (14). Recovery from FMDV and protection from reinfection are associated predominantly with the presence of circulating neutralizing antibody (20, 25, 32).Transmission of FMDV between animals is primarily via oral-pharyngeal exposure from contaminated feed and aerosols emitted from infected animals. This has led to a particular interest in the local, mucosal immune response to FMDV infection in the pharynx since, following exposure, this region is the most common site for primary virus replication (30, 36). Unfortunately, analysis of mucosal immunity has essentially been limited to assessment of immunoglobulin A (IgA) responses to FMDV infection of swine. Alternatively, the virus can gain direct entry into the skin through cuts or abrasions, particularly during infection of swine, as reviewed by Alexandersen and colleagues (2). The latter route of viral entry is more common in swine than in other susceptible species.The role of T cells in stimulating B cell proliferation and subsequent differentiation to high-affinity antibody production in the swine response to FMDV is of particular interest. In the response of other species to different pathogens, it has been clearly demonstrated that both Th1 and Th2 responses contribute to effective immunity and clearance of pathogens (4, 26, 28, 33, 34). Manipulating vaccine formulations to target immune responses will be useful for FMDV prophylactics in swine and cattle, but the present knowledge of immune responses in these species offers little insight into the importance of the Th1/Th2 paradigm in effective antiviral immunity. Thus, extrapolating the Th1/Th2 paradigm of mice to swine is problematic.In mice, the B cell switch from IgM to IgG2b antibody secretion is mediated by Th1 cytokines, specifically, gamma interferon (IFN-γ), whereas Th2 cytokines, including interleuken-4 (IL-4), IL-5, IL-13, and transforming growth factor β (TGF-β), accompany class switch to IgG1, IgG3, IgE, and IgA. However, IgG1 and IgG2b are not homologous immunoglobulins among distantly related mammals since speciation preceded subclass diversification (13, 23).Further complicating our understanding of antibody responses in pigs is the fact that there are six subclasses of porcine IgG, five of which occur in at least two allelic forms (13). IgG1 is transcribed predominately in fetal and adult swine but not in the ileal Peyer''s patches and mesenteric lymph nodes of fetal and neonatal piglets, where IgG3 predominates (11). IgG2 is poorly transcribed in all tissues of fetal and neonatal piglets. IgG3, the primordial porcine IgG, is most 5′ in the CH locus and, based on sequences motifs, is best equipped to activate complement and bind to Fcγ receptors (13, 17a). Currently, only two monoclonal antibodies (MAbs) that are described as specific for IgG1 and IgG2 are available. Based on preliminary results, anti-IgG1 is quite likely IgG1 specific, whereas the anti-IgG2 MAb likely recognizes an infraclass group that includes IgG2, IgG4, and IgG6. Since purified forms of IgG4 and IgG6 are not yet available, this has yet to be tested.There are other factors that complicate understanding antibody responses to viral infection of mucosal surfaces in swine. In their studies on the distribution of antibody-containing cells, Bianchi and colleagues recognized differential reactivities among anti-porcine IgA MAb, which they suggested might reflect different IgA subclasses, as in humans (3). At nearly the same time, the porcine Cα gene was cloned and was shown to occur in two allelic forms, one of which was missing 4 amino acids of the hinge due to a splice accepter site mutation (5, 6). Sera from swine homozygous for IgAa and IgAb were exchanged to show that the MAbs generated by Bianchi and colleagues differentially recognized the two allotypic variants (29). The distribution of the two allotypes appears to be founder and breed associated, with IgAa occurring in the highest frequency (29).The study reported here focuses on the mucosal antibody response of swine and utilizes isotype-specific reagents in two different, sensitive enzyme-linked immunosorbent assays (ELISAs). The comparison of assays for determination of the quality of antibody responses to FMDV addresses the limitations of presently available reagents. We tested for antibody responses in serum and saliva at 7, 14, or 21 days postvaccination (dpv) with a single dose of vaccine and compared the responses to those resulting from direct inoculation of pigs or following contact transmission of infection. FMDV-specific IgA, IgM, and IgG antibodies were readily detected in serum after infection, and IgA was detected in the saliva of the same animals. However, following vaccination, there were IgM and IgG responses in serum but no IgA antibodies in serum or saliva. These results illuminate the need to develop alternative FMDV vaccines designed for more efficient mucosal delivery and the induction of a mucosal IgA response that is predicted to yield better control of FMDV in an outbreak.     

EB病毒与胃癌

多种恶性肿瘤细胞内存在EB病毒（EBV）,本文综述了EBV和胃癌的关系,EBV相关胃癌的病理特点及临床诊断、治疗、预后的现状,并对存在的问题及进展作了简要介绍,     

An Antibody Targeting the Fusion Machinery Neutralizes Dual-Tropic Infection and Defines a Site of Vulnerability on Epstein-Barr Virus

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抗P选择素功能域单抗对人树突状细胞表型及IL-12分泌的影响

观察抗P选择素Lectin EGF功能域单抗 (PsL EGFmAb )对体外培养人树突状细胞 (DC )表型以及促炎细胞因子IL 1 2分泌的影响 ,探讨PsL EGFmAb对DC炎性成熟过程中的调节作用。通过SCF、GM CSF、TGF β1 、Flt 3和TNF α体外培养体系 ,从脐血CD34+ 造血干细胞中诱导扩增获得DC ,并于成熟中用PsL EGFmAb进行干预。采用流式细胞仪分析细胞表型CD1a、CD1 1c、CD83、CD80、CD86和HLA DR ;采用RT PCR检测IL 1 2p35、p4 0mRNA表达 ;以及ELISA法测定IL 1 2p70分泌的含量。结果显示 ,PsL EGFmAb可下调成熟中DC表面CD1 1c、CD83、CD80、CD86和HLA DR的表达 ,同时能抑制DC内IL 1 2p35、p4 0mRNA的转录和IL 1 2p70的分泌。本研究提示 ,PsL EGFmAb对DC黏附共刺激分子表达和促炎细胞因子合成具有抑制作用 ,并可能影响和调抑DC成熟及其提呈抗原功能     

Oligopeptide Induction of a Secondary Cytotoxic T-cell Response to Epstein-Barr Virus In Vitro

Three Epstein-Barr virus (EBV) nuclear antigen (EBNA)-encoded oligopeptide epitopes have been mapped, each capable of acting as a recognition determinant for class I-restricted lysis by CD8+ cytotoxic T lymphocytes (CTL). This report shows that each peptide, when presented on an appropriate autologous antigen-presenting cell (APC), also stimulates EBV-specific memory T cells present in peripheral blood mononuclear cell (PBMC) populations to develop in vitro into peptide-specific CTL. These CTL specifically lysed autologous EBV-infected lymphoblastoid cell lines (LCL) and peptide-sensitized uninfected targets. Identical viral oligopeptides could therefore function as recognition determinants for both the induction and commission of class I-restricted specific cytotoxicity. A model system is described in which autologous phytohaemagglutinin (PHA) blasts present exogenous peptide during the stimulation phase. The magnitude of the peptide-specific CTL response was dependent on the concentration of peptide added to the APC and specific lysis was inhibited by anti-class I monoclonal antibody (MoAb) but not anti-class II MoAb. Cultures depleted of CD8+ T cells by cell separation with immunomagnetic beads prior to stimulation invariably failed to generate a peptide-specific CTL response. However, the effect of CD4 depletion on CTL activity was equivocal and indicated that a need for CD4+ T cells as accessory helper cells may depend on the efficiency of the APC to elaborate their own help. This model has advantages in the analysis of events involved in the development of CTL activity in vitro.     

Guinea Pig Herpes-Like Virus Infection I. Antibody Response and Virus Persistence in Guinea Pigs After Experimental Infection

Guinea pigs, experimentally infected with guinea pig herpes-like virus produced antibodies which were detectable by indirect hemagglutination (IHA), complement-fixation (CF), and neutralization tests. The IHA test appeared to be a more sensitive method than the CF or neutralization test for determining antibody response in guinea pigs immediately after infection, but the IHA method was not suitable for the detection of antibody in animals receiving small doses of virus. Antibody titers obtained by CF tests were generally higher than those obtained by the neutralization test, and they followed the same time course when individual animals were studied serially. Intracardiac inoculation produced the best antibody response in guinea pigs when compared with other routes of infection. Guinea pigs infected by the intraperitoneal, intranasal, or oral route showed rising antibody titers but the levels were low. Infectious virus was isolated from and persisted in all inoculated animals in the presence of antibody regardless of the route of inoculation. Recovery of infectious virus required cultivation or cocultivation of tissue cells containing virus. The administration of antilymphocyte sera delayed the appearance of IHA antibody but had no effect on antibodies determined by the CF- and neutralization tests.     

Cytotoxic Antibody Response to Tumors Induced in Adult and Newborn Rabbits by Fibroma Virus

Cells cultured from tumors induced in rabbits by inoculation of fibroma virus possessed virus-specific cell surface and cytoplasmic antigens. Tumor cell cultures were capable of a limited number of cell divisions before degenerating. Employing the (51)Cr-release test and the microcytotoxicity test, it was demonstrated that sera from rabbits with regressed fibroma tumors contained antibodies cytotoxic for cells infected in culture with fibroma virus. These sera were only weakly cytotoxic for cultured fibroma tumor cells. In addition, newborn rabbits bearing progressively growing tumors had serum antibodies cytotoxic for cells infected with fibroma virus in culture but not for fibroma tumor cells. Immunofluorescence studies also showed that the reaction of immune serum with the surface antigens of fibroma tumor cells was markedly weaker than with the surface antigens of cells infected with virus in culture. Furthermore, membrane cytotoxicity and immunofluorescence reaction were significantly reduced when cells were tested after prolonged incubation or cell division, or both, following infection with fibroma virus. The failure of tumors to regress in newborn rabbits in spite of the presence of cytotoxic antibodies is discussed in respect to a possible reduction or alteration of virus-specific surface antigens on proliferating tumor cells.     

EHF病毒感染家兔后血清特异性抗体水平的动态观察

本文报告了流行性出血热病毒(Epidemic haemorrhagic fever virus,EHFV)J10、A9株分别感染实验家兔后,用反向间接ELISA(RIELISA)和间接免疫荧光(IFA)方法,动态观察了家兔特异性IgG抗体水平的变化。发现特异性IgG于感染后第1周开始出现,以后抗体水平稳步上升,于第5—7周便达到最高水平,高滴度的抗体可以维持较长时间。结果还表明;RIELISA检测家兔抗体的敏感性明显优于IFA法。用IFA进行的交叉反应还证实;EHFV-J10、A9两种毒株的抗血清能与不同来源的数株病毒发生特异性结合反应。     

Kinetics of the Neutralizing Antibody Response to Respiratory Syncytial Virus Infections in a Birth Cohort

The kinetics of respiratory syncytial virus (RSV) neutralizing antibodies following birth, primary and secondary infections are poorly defined. The aims of the study were to measure and compare neutralizing antibody responses at different time points in a birth cohort followed‐up over three RSV epidemics. Rural Kenyan children, recruited at birth between 2002 and 2003, were monitored for RSV infection over three epidemic seasons. Cord and 3‐monthly sera, and acute and convalescent sera following RSV infection, were assayed in 28 children by plaque reduction neutralization test (PRNT). Relative to the neutralizing antibody titers of pre‐exposure control sera (1.8 log₁₀ PRNT), antibody titers following primary infection were (i) no different in sera collected between 0 and 0.4 months post‐infection (1.9 log₁₀ PRNT_, P = 0.146), (ii) higher in sera collected between 0.5 and 0.9 (2.8 log₁₀ PRNT_, P < 0.0001), 1.0–1.9 (2.5 log₁₀ PRNT, P < 0.0001), and 2.0–2.9 (2.3 log₁₀ PRNT, P < 0.001) months post‐infection, and (iii) no different in sera collected at between 3.0 and 3.9 months post‐infection (2.0 log₁₀ PRNT, P = 0.052). The early serum neutralizing response to secondary infection (3.02 log₁₀ PRNT) was significantly greater than the early primary response (1.9 log₁₀ PRNT, P < 0.0001). Variation in population‐level virus transmission corresponded with changes in the mean cohort‐level neutralizing titers. It is concluded that following primary RSV infection the neutralizing antibody response declines to pre‐infection levels rapidly (～3 months) which may facilitate repeat infection. The kinetics of the aggregate levels of acquired antibody reflect seasonal RSV occurrence, age, and infection history. J Med. Virol. 85:2020–2025, 2013. © 2013 The Authors. Journal of Medical Virology published by Wiley Periodicals, Inc.     

Antibody Response of Hamsters to A2/Hong Kong Virus Vaccine after Priming by Heterotypic Virus Infection

Hamsters previously infected with influenza virus A1/FM/1/47 produced serum hemagglutination inhibition (HI) antibody in response to 1/100 the antigenic dose of inactivated influenza virus A2/Hong Kong vaccine necessary to induce antibody in normal animals. This priming effect was believed to be due to the virus infection which caused an immune response to a virus antigen common to both the infecting virus and the virus vaccine; this antigen acted as a carrier for the specific vaccine virus hemagglutinin and potentiated the immune response to the new antigen. This theory, which has been established in other immune systems, was tested, and the results obtained did not contradict the conditions imposed in the above explanation. Thus, the priming effect could be transferred to normal hamsters by inoculation of spleen cells from virus-infected animals, and the HI antibody response to the virus vaccine was characteristic of a secondary response. The theory also required that the new antigen be coupled to the carrier protein; however, primed hamsters produced serum HI antibody after inoculation with ether-Tween-split virus vaccine, but there was no proof that this vaccine was completely dissociated.     

False Positive Immunoglobulin M Antibody to Cytomegalovirus in Child with Infectious Mononucleosis Caused by Epstein-Barr Virus Infection

A 16-month-old boy was admitted because of cough that had lasted for 10 days. The patient showed severe hepatomegaly incidentally, and dual positivity of Immunoglobulin (Ig) M to Epstein-Barr virus (EBV) viral capsid antigen (VCA) and cytomegalovirus (CMV). On the basis of seroconversion to Epstein-Barr nuclear antigen (EBNA) Ig G positivity and reduced CMV Ig M titer with persistently negative CMV Ig G, a definite diagnosis of EBV-induced infectious mononucleosis was established 1 year 2 month later.     

Analysis of the Neutralizing Antibody Response to the Measles Virus Using Synthetic Peptides of the Haemagglutinin Protein

Infection or immunization with measles virus induces a protective immune reaction including neutralizing antibodies against the haemagglutinin and fusion protein. The reactivity of the polyclonal IgG response of sera obtained from late convalescent donors was studied, using overlapping 15mer peptides covering the complete sequence of the measles virus haemagglutinin. Most sera reacted with a similar set of peptides generating a characteristic binding pattern. The reactive peptides correspond to a region mediating cell hemolysis (aa310–325), to regions which serve as targets to neutralizing antibodies and to a putative transmembrane region (aa35–58). The latter region contains also a human T-cell epitope providing evidence of a non-random association of T- and B-cell epitopes. We also immunized different strains of mice and rabbits with measles virus. In contrast to the human sera, animal sera with strong neutralizing activities did not react with any of the H-protein peptides. The mostly weak reactivities with the linear sequences contrast with the strong neutralizing activities of the human or animal antibodies, suggesting that these primarily recognize the fusion protein or conformational epitopes of the haemagglutinin protein.     

Virus Antibody Levels and IgA Deficiency

IgA-deficient blood donors and their age- and sex-matched controls were compared for the occurrence of complement-fixing antibodies in serum against several viruses. The level in the IgA-deficient persons was slightly higher against several respiratory pathogens (adenoviruses, type B influenza virus, parainfluenza virus, and respiratory syncytial virus) that give rise to localized infections, and against coxsackie B group of viruses. No corresponding difference was observed in mumps, varicella, and cytomegalovirus infections, where viraemia is a characteristic feature, or in Mycoplasma pneumoniae infection.     

泛素-蛋白酶体途径与EBV潜伏蛋白

泛素-蛋白酶体途径是真核细胞内重要的蛋白质调控系统,参与调节细胞周期进程、细胞增生与分化,以及信号传导等多种细胞生理过程,因此,细胞内蛋白泛素化降解是蛋白质重要的转录后修饰方式。EBV编码多种病毒蛋白,通过泛素．蛋白酶体途径调节病毒的潜伏,使病毒能在免疫活性较高的宿主体中存活。LMP1和LMP2A可能作为泛素．蛋白酶体途径的底物而受其调控,EBNA1则充当蛋白酶体降解过程中的阻滞剂。对它们在该途径中不同作用的深入了解将促使我们发展治疗EBV相关癌症的新策略。