应用VIDAS免疫分析系统检测血清抗伯氏包柔螺旋体抗体

莱姆病（Ｌｙｍｅｄｉｓｅａｓｅ）是最近十年来才被认识的一种蜱媒传染流行病，Ｌｙｍｅ病的血清学诊断方法有间接荧光免疫法（ＩＦＡ），酶免疫试验（）ＥＩＡ），免疫印迹法（ＷＢ），梅里埃生物公司（Ｂｉｏｍｅｒｉｅｕｘ）推出ＶＩＤＡＳ免疫诊断系统能够自动定性和半定量地检查Ｌｙｍｅ病的抗伯氏包柔螺旋体抗（抗ＢＢ抗体）。本方法结合了酶和荧光免疫两种方法。硷性磷酸酶标记二抗的底物是４ｍｅｔｈｙｌｕｍｂｅｌｌｉｆｅ     

Histopathological studies on the local reactions induced by complete Freund's adjuvant (CFA), bacterial lipopolysaccharide (LPS), and synthetic lipopeptide (P3C) conjugates

The inflammatory reactions following subcutaneous application of adjuvants revealed characteristic pathological patterns. The injection of complete Freund's adjuvant (CFA) resulted in the formation of large lipid deposits encircled by an inflammatory reaction and concentrically arranged collagen bundles. Bacterial lipopolysaccharide (LPS) caused granulomatous aggregations of mononuclear cells with thrombotic vessel occlusions. Inoculation of the lipopeptide adjuvants induced accumulation of mononuclear cells with only minimal fibrotic changes which were resolved after day 28. Lipopeptide conjugates based on the head group tripalmitoyl-S-glyceryl-cysteinyl-serin (P3CS) can thus be used as effective immunogens and adjuvants without long-term tissue damage.     

Recognition of a novel naturally processed, A2 restricted, HCV-NS4 epitope triggers IFN-gamma release in absence of detectable cytopathicity

Using short term CTL lines derived from HLA A2/K^b transgenic mice and IFN-gamma release assays we demonstrate that the NS4.1769 epitope, is generated from natural processing of the NS4 antigen, and presented in the context of the A2/K^b molecules. Interestingly, T cell recognition of the naturally processed form of the NS4.1769 epitope was associated with significant IFN-gamma release, but no direct cytolytic activity. Epitopes of this phenotype might be of interest, in terms of therapy of chronic HCV infection by associating the benefit of localized lymphokine release with low or absent direct cytopathicity.     

Shared allergenic and antigenic determinants in Alternaria and Stemphylium extracts

To develop a model for mold allergen extract standardization, we studied eight commercial Alternaria extracts from various suppliers by a variety of immunochemical and physicochemical techniques, including measurement of Alt-I, a purified allergenic fraction of Alternaria. Wide variations were noted in the allergenic and antigenic potencies of these extracts. Estimates of Alt-I content measured by Alt-I RAST inhibition and by radioimmunoassay correlated significantly (p < 0.05), but Alt-I activity by either method could not be correlated with allergenic potency as measured by RAST inhibition using solid-phase Alternaria. Each test extract produced unique and differing patterns of Coomassie blue-stained bands in isoelectrofocusing gels and in crossed immunoelectrophoresis gels using rabbit antibodies to Alternaria. The optimal method for mold allergen standardization involves a combination of RAST inhibition, isoelectrofocusing, and crossed immunoelectrophoresis techniques, and, if possible, quantitation of individual allergens.     

Influence of Various Immunomodulators on the Induction of Experimental Autoimmune Encephalomyelitis in Lewis Rats

The effect of various immunomodulators on the induction of experimental autoimmune encephalomyelitis (EAE) is evaluated in the Lewis rat. Bordetella pertussis (BP) is the optimal inductor of EAE in this rat strain. Treatment of the animals with BP either before or after or simultaneously with guinea-pig spinal cord preparation (GpSC) resulted in an EAE about two weeks thereafter. Additional injection of living BCG, of CFA, IFA (incomplete Freund's adjuvant) or Vibrio cholerae neuraminidase (VCN) did not augment or mitigate the effect induced by BP or GpSC. Living BCG, IFA, VCN or Corynebacterium parvum (CP) did not induce EAE when given in combination with GpSC but without BP. CFA combined with GpSC only occasionally induced EAE. However, EAE could be induced by the combination of CFA and GpSC or IFA and GpSC in a part of the animals tested if they had been pretreated or simultaneously been injected with living BCG by intravenous route. EAE could not be enhanced by the additional injection of VCN. Surprisingly, most of the animals peracutely died after injection of CFA and BP in combination with GpSC when they had been pretreated with CP. This effect was most pronounced when pretreatment was done on day -4. No acute effect could be seen when CP was given simultaneously to CFA, BP and GpSC. Animals which did not peracutely succumb developed EAE similarly as those in the positive control groups. CP treatment simultaneously with BP but without CFA resulted in a reduction of the EAE specific mortality. This reduction could not be seen if treatment with CP was done after injection of GpSC and BP.     

Diagnostic tools for Toscana virus infection

Toscana virus (TOSV; Phlebovirus, Bunyaviridae) is an important etiological agent of acute meningitis and meningoencephalitis in Mediterranean countries. Laboratory diagnosis has been carried out in serological studies using ELISA, immunofluorescence and/or neutralization tests that are not influenced by the virus viability; however, in the acute phase of the infection, nucleic acid amplification techniques are the methods of choice to diagnose viral meningitis from cerebrospinal fluid samples. Molecular methods are rapid and sensitive and, unlike traditional methods, such as virus isolation by cell culture, they are not influenced by the viability of the virus in the clinical specimen; however, the RNA integrity is crucial for the success of these methods. Real-time PCR is the most important molecular method used in laboratories worldwide, since it is less time-consuming and it reduces the risk of contamination. Therefore, a sensitive real-time PCR has been developed for diagnosis of suspected cases of TOSV infection either autochthonous and/or imported, since a new lineage of TOSV, divergent from the Italian prototype, has recently been reported in Spain.     

Plasmodium falciparum synthetic LbL microparticle vaccine elicits protective neutralizing antibody and parasite-specific cellular immune responses

Epitopes of the circumsporozoite (CS) protein of Plasmodium falciparum, the most pathogenic species of the malaria parasite, have been shown to elicit protective immunity in experimental animals and human volunteers. The mechanisms of immunity include parasite-neutralizing antibodies that can inhibit parasite motility in the skin at the site of infection and in the bloodstream during transit to the hepatocyte host cell and also block interaction with host cell receptors on hepatocytes. In addition, specific CD4+ and CD8+ cellular mechanisms target the intracellular hepatic forms, thus preventing release of erythrocytic stage parasites from the infected hepatocyte and the ensuing blood stage cycle responsible for clinical disease. An innovative method for producing particle vaccines, layer-by-layer (LbL) fabrication of polypeptide films on solid CaCO₃ cores, was used to produce synthetic malaria vaccines containing a tri-epitope CS peptide T1BT* comprising the antibody epitope of the CS repeat region (B) and two T-cell epitopes, the highly conserved T1 epitope and the universal epitope T*. Mice immunized with microparticles loaded with T1BT* peptide developed parasite-neutralizing antibodies and malaria-specific T-cell responses including cytotoxic effector T-cells. Protection from liver stage infection following challenge with live sporozoites from infected mosquitoes correlated with neutralizing antibody levels. Although some immunized mice with low or undetectable neutralizing antibodies were also protected, depletion of T-cells prior to challenge resulted in the majority of mice remaining resistant to challenge. In addition, mice immunized with microparticles bearing only T-cell epitopes were not protected, demonstrating that cellular immunity alone was not sufficient for protective immunity. Although the microparticles without adjuvant were immunogenic and protective, a simple modification with the lipopeptide TLR2 agonist Pam₃Cys increased the potency and efficacy of the LbL vaccine candidate. This study demonstrates the potential of LbL particles as promising malaria vaccine candidates using the T1BT* epitopes from the P. falciparum CS protein.     

A recombinant varicella vaccine harboring a respiratory syncytial virus gene induces humoral immunity

The varicella-zoster virus (VZV) Oka vaccine strain (vOka) is highly efficient and causes few adverse events; therefore, it is used worldwide. We previously constructed recombinant vOka (rvOka) harboring the mumps virus gene. Immunizing guinea pigs with rvOka induced the production of neutralizing antibodies against the mumps virus and VZV.Here, we constructed recombinant vOka viruses containing either the respiratory syncytial virus (RSV) subgroup A fusion glycoprotein (RSV A–F) gene or RSV subgroup B fusion glycoprotein (RSV B–F) gene (rvOka-RSV A–F or rvOka-RSV B–F). Indirect immunofluorescence and Western blot analyses confirmed the expression of each recombinant RSV protein in virus-infected cells. Immunizing guinea pigs with rvOka-RSV A–F or rvOka-RSV B–F led to the induction of antibodies against RSV proteins. These results suggest that the current varicella vaccine genome can be used to generate custom-made vaccine vectors to develop the next generation of live vaccines.     

卡氏肺孢子虫感染的免疫诊断研究

目的：探讨肺泡灌洗液、血清抗原及血清抗体检测诊断卡氏肺孢子虫感染的价值。方法：利用免疫抑制大鼠模型及双夹心ＥＬＩＳＡ法检测不同时期感染大鼠肺泡灌洗液和血清中肺孢子虫抗原，用ＩＦＡ法检测血清中的肺孢子虫ＩｇＧ抗体，并与病原学检查结果进行比较。结果：感染大鼠肺泡灌洗液的抗原检测于免疫抑制６－８ｗｋ后均呈阳性，而对照组大鼠均呈阴性；大多数感染大鼠血清抗原检测为阴性；正常大鼠血清中有低滴度肺孢子虫ＩｇＧ抗体，感染大鼠抗体滴度轻度升高或不升高，但中止免疫抑制后血清抗体滴度明显升高，而肺泡灌洗液中抗原逐渐阴转。结论：肺泡灌洗液抗原检测可用于肺孢子虫感染的诊断，但血清中很难检出这种抗原；血清ＩｇＧ抗体的上升并不表示为现症感染。     

马来丝虫感染沙鼠血清中特异性抗体水平的动态研究

应用马来丝虫和牛丝虫成虫冰冻切片抗原作IFAT和IEST检测马来丝虫感染长爪沙鼠血清中抗体IgG和IgM水平的动态变化,结果分别在感染后12～14周及2～6周达高峰。感染沙鼠IgG水平与感染时期长短密切相关,但与感染度无关。认为IFAT和IEST,特别是后者,可望成为丝虫病诊断中较为理想的方法;牛丝虫抗原可望能代替马来丝虫抗原用于丝虫病血清诊断中。