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.     

Grading score system: A method for evaluation of the degree of senescence in Senescence Accelerated Mouse (SAM)

For evaluation of the degree of senescence in SAM-P, accelerated senescence prone mouse, formerly called SAM or prone series or P-series, consisting of SAM-P/1, SAM-P/2, SAM-P/3 and SAM-P/4 corresponding to P-1, P-2, P-3 and P-4 series, respectively, in the previous reports, and in SAM-R, accelerated senescence resistant mouse, formerly called resistant series or R-series, consisting of SAM-R/1, SAM-R/2 and SAM-R/3 corresponding to R-1, R-2 and R-3 series, respectively, in the previous reports, the grading score system was adopted. The items to be examined in this system include 11 categories selected from the clinical signs and gross lesions considered to be associated with the aging process. The degree of the senescence in each category was graded from 0 to 4 according to the detailed criteria devised in our laboratory. After 8 months of age each mouse was examined every 4 months, and some of the mice were examined after 2 months of age.In almost all categories, the grading score and incidence began to increase from 4 or 6 months of age and continued to increase with advancing age in both SAM-P and SAM-R. The increase, however, was more marked in SAM-P than in SAM-R. The slow but steady increase in the SAM-R levelled out at 24 months of age and was comparable to that of 12 months of age in SAM-P. In both SAM-P/1 at 8 months of age and SAM-R/2 at 12 months of age, there was a significant reverse correlation between total score of this grading score system and length of residual life after examination.Systematic and extensive studies using the grading score system showed that if the validity of the system is, based on “irreversibility” and “universality” of the changes in     

肾细胞癌中c-erbB-2表达及其意义

目的子研究c—erbB-2在肾细胞癌中的表达及其与临床分期、病理分型、病理分级和预后的关系。方法 应用免疫组化S-P法分别用鼠抗人c-erbB-2胞内段单克隆抗体(CB11)和鼠抗人c-erbB-2胞外段单克隆抗体(9G6．10)检测77例肾细胞癌及相应癌旁肾组织c—erbB-2蛋白表达。应用RT-PCR方法检测10例新鲜肾癌组织及癌旁正常组织c—erbB-2 mRNA的表达。透明细胞癌、颗粒细胞癌及乳头状肾细胞癌c—erbB-2的表达分别为68．2％、93．1％及75．0％。结果 77例肾癌组织CB11和9G6．10的阳性率分别为61%(47／77)和45．5%(35／77)；二者联合检测总阳性率为77．9％(60／77)。透明细胞癌、颗粒细胞癌及乳头状肾细胞癌c—erbB-2的表达分别为68．9％、92．9％及75%。RT-PCR检测新鲜肾癌组织c—erbB-2mRNA的阳性率为100％(10／10)。结论 肾癌中c—erbB-2蛋白及c—erbB-2mRNA均过表达。不同的肾癌病理类型c—erbB-2蛋白表达不同，颗粒细胞癌表达最高。c—erbB-2在肾癌的不同临床分期均过表达，说明可能在病变的早期c—erbB-2已经发生改变。c-erbB-2的表达与临床分期及肿瘤分级无明显相关性。     

Enzyme-immunoassay in diagnosis of hepatitis with emphasis on the detection of "e" antigen (HBeAg).

A brief survey of the application of enzyme-immunoassay (EIA) for the detection of hepatitis B surface antigen (HBsAg), hepatitis A, and their corresponding antibodies is given. The preliminary results of a similar EIA for detection of hepatitis B-related "e" antigen (HBeAg) and its antibody (anti-HBe) are reported. This EIA is much more sensitive than immunodiffusion: at least 128 times for HBeAg and at least 512 times for anti-HBe. HBsAg and its antibody do not interfere with the test. Only a few sera strongly positive for rheumatoid factor gave rise to false-positive results, as was demonstrated by a confirmatory test.     

Different ion channel mechanisms between low concentrations of capsaicin and high concentrations of capsaicin and nicotine regarding peptide release from pulmonary afferents

Vagal nerve stimulation (1 Hz for 1 min), capsaicin (10^-8 M and 10^-6 M), resiniferatoxin (3 × 10^-10 M) and nicotine (10^-4 M) evoked a non-cholinergic bronchoconstriction in the isolated perfused guinea-pig lung preparation. Simultaneously there was an increase in the perfusate levels of calcitonin gene-related peptide-like immunoreactivity, suggesting release from sensory nerves. Both the bronchoconstriction and peptide release evoked by a low concentration of capsaicin (10^-8 M) and that evoked by nerve stimulation were depressed by tetrodotoxin, suggesting involvement of Na⁺ channel dependent depolarization. Since the effects of capsaicin (10^-8 M) and vagal nerve stimulation were inhibited by ω-conotoxin but not influenced by nifedipine, the Ca²⁺-channel involved is probably of N-type. Furthermore, the capsaicin analogue resiniferatoxin also evoked ω-conotoxin sensitive peptide release and bronchoconstriction. At the higher capsaicin concentration (10^-6 M), the functional response was only slightly inhibited by wconotoxin or tetrodotoxin indicating that capsaicin at this concentration evoked peptide release and functional effects through other mechanisms, probably involving Ca²⁺ fluxes in the non-selective cation channel associated with the proposed capsaicin receptor. The nicotine (10^-4 M) evoked peptide release and bronchoconstriction were only marginally influenced by ω-conotoxin or tetrodotoxin. It is concluded that the ion-channel mechanisms underlying the peptide releasing properties of antidromic nerve stimulation and low concentrations of capsaicin are similar and depend on action potential propagation, whereas capsaicin in high, toxic concentration and nicotine mainly act via receptor operated channels.     

The pharmacology of fever

The ability to minimise, if not prevent, large variations in deep body temperature that would otherwise result from some environmental conditions is a homeostatic function of unquestioned benefit that is demonstrated only by the more highly evolved animals. Nevertheless, body temperature is raised above normal values in many pathological conditions. This increase in temperature or fever is an active and co-ordinated response, which indicates the involvement of the CNS. Central injection and lesion studies have shown that the brain, in particular the PO/AH, is the site of action of fever-inducing agents, termed pyrogens. Electrophysiological data show that pyrogens modify the activity of central thermosensitive neurones as if to increase heat gain and decrease heat loss. The common response of fever to pyrogens of diverse origins is attributable to fever being mediated by an endogenous pyrogen released by phagocytic cells in the host. The mechanism by which central neuronal function is disturbed by pyrogens present in the periphery is not known. Tracer studies have yet to demonstrate the passage of a pyrogen across the blood-brain barrier. The possible involvement of several putative neuro- transmitters and modulators in fever has been reviewed here, but most compounds have not been studied sufficiently to allow firm conclusions to be drawn. Much of the data is limited to the effects of the putative mediators on normal thermoregulation but, even when the effect is hyperthermia, such observations do not necessarily indicate a role for the endogenous material in fever. Dose-response curves for agonists and the effects of antagonists are often undetermined. This shortfall in data is due to some extent to the nature of fever; a central response in vivo over several hours. Although fever may enhance other host reactions to combat infection and inflammation, neither this benefit nor the undesirability of antipyretic therapy has been demonstrated unequivocally in either homeothermic laboratory animals or humans. Consequently, antipyretic drugs continue to be used clinically to alleviate the fever, malaise and/or pain commonly associated with disease. The drugs in common usage are the nonsteroidal antipyretic analgesics, many of which also have an anti-flammatory effect. The primary mode of action of these drugs as antipyretics appears at present to be the inhibition of cyclo-oxygenase and a consequent reduction of prostanoid material in pyrogen-sensitive areas of the brain. PGEs in the PO/AH have received most study to date, but other mediators in other parts of the CNS, where the density of pyrogen receptors may be sparse, cannot be discounted and await further investigation.     

Complex pattern of Th1 and Th2 activation with a preferential increase of autoreactive Th1 cells in BALB/c mice with proteoglycan (aggrecan)-induced arthritis

The central role of CD4+ T cells and the balance between T helper (Th) subpopulations in the pathogenesis of autoimmune diseases have been extensively studied. Proteoglycan (aggrecan)-induced arthritis (PGIA) is a murine model for rheumatoid arthritis (RA), which is characterized by a Th1 dominance at the onset of the disease. In addition to CD4+ T cells, antigen-presenting B cells and autoantibodies seem to play an important role in the development and regulation of PGIA. To identify proteoglycan-specific CD4+ T cell subsets and Th1- and Th2-supported antibody isotypes during the progression of PGIA, spleen cells of proteoglycan-immunized BALB/c mice were harvested at different times of immunization, and at different stages of the disease, and their cytokine production and antigen-specific antibody isotype profiles were determined by enzyme-linked immunospot (ELISPOT) assays. Both Th1 and Th2 cytokine-producing cells, with the predominance of IL-4/IL-5-secreting cells, were detected during the prearthritic stage, and a shift toward a Th1 dominance was observed at the time of onset of arthritis. Tissue homogenates of acutely inflamed joints contained significantly higher levels of interferon-gamma than IL-4. The prearthritic period and both the acute and chronic phases of joint inflammation were characterized by IgG1 dominance in the sera and this correlated with the number of IgG1-secreting B cells in the spleen. However, the ratio of autoreactive IgG1/IgG2a-secreting cells decreased in arthritic animals. These results indicate the activation and possible regulatory roles of both Th1 and Th2 subsets in the autoimmune process, with the necessity of a relative increase of autoreactive Th1 cells for the induction of joint inflammation.     

BMP4 is required in the anterior heart field and its derivatives for endocardial cushion remodeling, outflow tract septation, and semilunar valve development

The endocardial cushions play a critical role in septation of the four-chambered mammalian heart and in the formation of the valve leaflets that control blood flow through the heart. Within the outflow tract (OFT), both cardiac neural crest and endocardial-derived mesenchymal cells contribute to the endocardial cushions. Bone morphogenetic protein 4 (BMP4) is required for endocardial cushion development and for normal septation of the OFT. In the present study, we show that anterior heart field (AHF)-derived myocardium is an essential source of BMP4 required for normal endocardial cushion expansion and remodeling. Loss of BMP4 from the AHF in mice results in an insufficient number of cells in the developing OFT endocardial cushions, defective cushion remodeling, ventricular septal defects, persistent truncus arteriosus, and abnormal semilunar valve formation.