Effective control of foot-and-mouth disease (FMD)--prevention, surveillance and response--requires integrated animal disease management as a cooperative effort between stakeholders, scientists and decision makers, at all levels: local, national, regional and international. This paper suggests a process and outlines specific critical issues that need to be addressed in order to best use the science and technology that is available now and to develop new technologies that will lead to significant improvements. The overall objective is not to allow the disease or the disease control measures to damage, violate or destroy public health, the environment, or the economy, or to allow politics to drive disease control policies at the expense of the ethical relationship between man and animals. Critical issues of prevention, surveillance and response policies are examined, and specific recommendations are made to reduce the risk or effect of natural and deliberate introductions. For prevention: a) rapid portable diagnostics and provision of vaccines to control and eradicate the reservoirs of disease. b) alerts, leading to increased controls at borders, animal movement restrictions and biosecurity on farms. For surveillance: a) reporting of unusual symptoms, rapid diagnostics and identification of patterns. b) enhanced role of geographic information systems (GIS) linked to an IT system. c) collection, storage and sharing of disease information. For response policies: a) the role and implementation of stamping out and of vaccination. b) simulation exercises with stakeholder participation. For all aspects of FMD control, consideration should be given to: a) the composition, responsibilities and role of the balanced, permanently operational Expert Group in EU member states as specified in the EU FMD Directive. b) establishment of a balanced, permanently operational European Expert Group. c) establishment of both a European and an International FMD Task Force. Stakeholders need access to accurate, up-to-date, unbiased information about the science of disease control, how the technologies work and can be used, and an assurance that the technologies best fit for the required purpose will be used. Researchers need to work together to avoid duplications and gaps in their research and to recognise the benefit of new, and sometimes innovative, technologies. They also need feedback from stakeholders on the acceptability and best use of the technologies. A process to achieve these goals through an EU funded collaborative research project will be described.
The aetiology of schizophrenia and the other psychoses is not yet established. The Knight model, based on genetic and other evidence, proposes that schizophrenia is an autoimmune disease, caused by the development of forbidden clones of B lymphocytes that secrete autoantibodies that accidentally stimulate cell surface receptors on certain neurons, affecting the limbic system of the brain. An unusual defect in a Maori man with Graves' disease rendered him unresponsive to the usually effective antithyroid drugs, prompting his being treated with prednisone, a non-specific immunosuppressant agent. This was highly successful, reducing the blood level of the causative thyroid-stimulating autoantibodies with reduction of thyroid hormone levels and thyroid gland size. Unfortunately, high dosage prednisone can be used for only a month, because of steroid toxicity. A research pathway to effective therapy of receptor-mediated autoimmune diseases, which probably include the psychoses, is now apparent. It involves finding the autoantibodies, then cloning of their antigenic targets, as has been done for Graves' disease. This will provide knowledge of the peptide sequences necessary for constructing therapeutic agents for selectively destroying the pathogenic forbidden clones. Meanwhile, usage of short-term therapy with prednisone could be helpful in the management of schizophrenia and should be explored.
Natural measles virus infection is recognised to induce immunosuppression, contributing to an increased susceptibility to other infections. A cell population that could be involved in this process is the CD8CD57 double-positive lymphocyte subset (CD8+CD57+), known to be significantly expanded in some viral infections, e.g. human immunodeficiency virus (HIV) infection. We therefore studied the level of CD8+CD57+ lymphocytes during measles infection and measles vaccination. Twenty-two measles patients were examined 5-57 days after the onset of fever and several months later. Healthy, age-matched controls were examined twice. Eleven children receiving measles-mumps-rubella (MMR) vaccination were examined before, 9-19 days and 5-9 months afterwards. Blood samples were analysed for the proportion of peripheral blood mononuclear cells carrying both CD8 and CD57, and for other cell surface markers (CD4, CD14, CD3, CD16(CD56) or CD20). Elevated proportions of CD8CD57 double-positive cells were found in the peripheral blood of children with natural measles early after infection (p < 0.05), whereas the proportion of other cell surface markers remained stable. No corresponding change in CD8+CD57+ lymphocytes was noted in MMR-vaccinated children or in healthy controls. Since CD8+CD57+ lymphocytes could be related to the immunosuppression seen in some viral infections, our finding of elevated CD8CD57 double-positive lymphocytes during acute measles infection would suggest that this population of lymphocytes is involved in measles-induced immunosuppression. The absence of an increase of CD8CD57 in children vaccinated with the conventional live attenuated measles vaccine, in contrast to children with natural measles infection, would thus indicate that the vaccine does not induce immunosuppression as measured in our in vitro system.
Bovine spongiform encephalopathy (BSE) is a neurological disease of cattle. Antibody responses to Acinetobacter radioresistens and six other bacteria, as well as to bovine myelin basic protein and bovine neurofilaments were measured in 128 BSE positive animals, 63 BSE negative animals and 64 healthy control animals. Animals positive for BSE had the highest levels of antibodies to Acinetobacter radioresistens (p < 0.0001) and also autoantibodies to bovine myelin basic protein (p < 0.0001) and bovine neurofilaments (p < 0.0001). In an endeavour to develop an antemortem test for BSE, 12 different strains of Acinetobacter were further tested in a MAN (myelin-Acinetobacter-neurofilament) assay involving 28 BSE positive and 18 BSE negative animals and defined bovine brain peptides. Five out of the 12 Acinetobacter bacteria tested [Acinetobacter (sp3), A. haemolyticus (sp4), A. johnsonii (sp7), A. lwoffii (sp8) and Acinetobacter (sp9)] gave 100% sensitivity and 100% specificity for detecting BSE. The highest anti-bacterial antibody level compared to controls was obtained with A. johnsonii. Further field studies are required to determine the validity of the MAN assay in detecting animals affected with BSE.
This mini-review highlights the growing number of indications for the immunological importance of pregnancy-associated plasma protein-A (PAPP-A), which is a remote member of the alpha-macroglobulin plasma protein family. PAPP-A can bind a variety of cytokines and specifically cleave a binding protein for insulin-like growth factors, thereby serving as a modulator of cytokine activity. Important immune functions, such as lymphocyte proliferation response to alloantigens and lectins and expression of HLA-DR molecules are predominantly suppressed in vitro by PAPP-A. It is likely that the immunoregulatory properties of PAPP-A are very similar to that of alpha 2-macroglobulin. The experimental data allows us to suppose that PAPP-A serves to prevent the recognition of the fetus by the maternal immune system and to suppress locally the host's immune response to the tumour.
The immunity system has the daunting task of producing lymphocyte clones able to react with any pathogenic microbe, new or old, to defend against infectious disease. It cannot do this without occasionally producing a forbidden clone, Burnet's apt name for the pathogenic lymphocyte clones that cause the autoimmune diseases by accidentally reacting with a host antigen instead of an antigen on an invading microbe. Unfortunately, Burnet's insight has been lost by immunologists, for four decades. V genes code for the specificity of receptors for antigen on B and T lymphocytes. They change by the DNA sequence copying errors (somatic mutations) that create new clones during the lymphocyte cell divisions that occur in an immune response to microbial infection. These mutations are necessary for achievement of the higher affinity, between a lymphocyte clone and the microbe, that enables recovery from infectious disease. H genes code for histocompatibility antigens, major, minor and HY. These are peptides, which, unlike V gene products, are invariant throughout life. H genes dictate the immune repertoire by constantly deleting any nascent lymphocyte clone reactive with them. This protects, with imperfect success, against autoimmune disease arising from the V gene changes that produce forbidden clones. Microbial triggers cause an autoimmune disease by initiating a cascade of clonal development that produces a forbidden clone by unlucky somatic mutations in lymphocyte V genes, exemplified by group A streptococci triggering rheumatic fever and measles triggering encephalomyelitis. Specific immunotherapy will come from finding and targeting forbidden clones.
Raised levels of circulating natural antibodies (NABS) have been found in association with systemic lupus erythematosus (SLE) and chronic active hepatitis (CAH), indicative of polyclonal B-cell activation associated with these relatively non-organ specific autoimmune diseases. This study examined the natural antibody response in the organ-specific autoimmune disease Hashimoto's thyroiditis. Serum samples obtained from 69 women with newly diagnosed Hashimoto's thyroiditis together with 64 controls were analysed for IgG and IgM NABS directed at DNA, actin, myoglobin, myosin, trinitrophenyl hapten (TNP) and tubulin as the NAB antigen panel using an established ELISA. The same technique was also used to estimate thyroglobulin and thyroid microsomal autoantibody activities. Compared to a reference panel of normal serum samples, 31 of the Hashimoto's samples showed a greater than 2SD elevation of IgG and/or IgM NABS against one or more of the panel antigens together with elevated IgG thyroglobulin and thyroid microsomal antibody levels. The cases positive for one or more of the NAB panel also showed a greater incidence of active Hashimoto's thyroiditis as indicated by the presence of antibodies directed against the thyroid specific antigens. The above findings suggest that raised levels of NABS are also a feature of this organ-specific autoimmune disease. The wide ranging NAB specificities involved are consistent with an underlying or epiphenomenal state of polyclonal B-cell activation.
Anti-thyroid peroxidase (TPO) antibodies, from patients with autoimmune disease, bind predominantly to two neighbouring, non-identical, conformational domains referred to as domains A and B. In recent years a number of ELISA assays have been developed for the detection of anti-TPO antibodies, however, considerable variation between the different commercial assay kits has been documented in inter-laboratory surveys (UK NEQAS). This investigation assessed the differences between nine commercial ELISA assays currently available in the UK. The anti-TPO kits varied in terms of their imprecision and accuracy and in the density of coated antigen. Recombinant antigen containing kits demonstrated partial destruction of the B epitope, possibly due to the close proximity of both epitope regions in the recombinant molecule. None of the kits expressed only one epitope although there were differences in the degrees of expression of each epitope. Clinicians should be aware of the variability of the numbers generated, when interpreting test results.
We investigated the effect of a potent synthetic steroid, budesonide (BUD), on the survival of nasal polyp (NP) derived eosinophils (EOS). BUD, at the highest dose used, 10(-6) M, decreased this survival but only by approximately one third. We speculated that the relatively small inhibitory effect of budesonide on the survival of NP-EOS could be the result of these EOS being exposed to substantial amounts of GM-CSF, IL-5 or IL-3. In this regard, we detected 148 pg of GM-CSF per 150 mg of tissue, which approximately contained 106 of eosinophils, in the supernatant of NP explants for 24 h without any stimulation. Contents of both IL-5 and IL-3 were much less. We further studied survival of PB-EOS exposed to rhGM-CSF and found that 10(-6) M of BUD could only inhibit by less than one third the survival of PB-EOS exposed to an amount of rhGM-CSF, similar to that detected in the supernatant of NP explants. In addition, we exposed PB-EOS to 200 pg/ml of rhGM-CSF for a relatively long period of time (4 days) in order to mimic chronic exposure in the tissue and found that the survival of these cells was prolonged to the extent similar to that observed in NP-EOS. Our data suggests that the prolonged spontaneous survival of NP-EOS ex vivo is likely the result of sustained in vivo exposure to GM-CSF and budesonide has a smaller inhibitory effect in the survival of these eosinophils as compared to those from peripheral blood.
Radiolabeled leukocytes have a potential for clinical use in detecting sites of inflammation. The increasing interest in the use of Tc-99m-labeled white blood cells (WBC) encourages exploration into the site(s) of binding of Tc-99m to the WBC components. Here we present the differential centrifugation study of the labeled leukocytes using a simple and low cost technique (SnTec). The results show most part of radioactivity bound to cytosol. We concluded that this is an intracellular labeling procedure that has the citoplasm, ribosomes unbound to membrane and soluble molecules as targets.
Densiometric quantitation and spreadsheet normalization were used to refine the parameters defining a treponemal Western blot (TWB) test for syphilis. Initially using 84 defined reactive and 105 defined non-reactive sera, we determined that the immune response to the 17 kDa antigen was the most critical of the following three candidate test determinants: the 47 kDa, 17 kDa and 15.5 kDa bands. In a second study using 124 cases of clinically diagnosed syphilis and 354 "normal" donors, a diluted serum sample was included as a minimal reactive control for the 17-kDa immune response. Reactivity to all three test determinants was obligatory for a test result to be interpreted as positive. Of the 124 cases of syphilis, 7 were nonreactive by TWB (sensitivity = 94%); of the 354 normal donors, 7 tested reactive (specificity = 98%). Forty (11%) normal serum samples had detectable but less than minimal reactivity to the 17 kDa band. Frequencies of immune response to a larger group of 12 antigens were tallied for the 124 clinically diagnosed cases of syphilis and an equal subset (124) of the normal group. In the normal subset, 72% and 52% of the samples had detectable reactivity to the 47 and 15.5 kDa antigens, respectively, while 10%, 5% and 3% reacted with the 17, 24 and 44.5 kDa antigens, respectively. Follow-up TWB testing of the clinically diagnosed cases revealed that previously untreated patients with primary or secondary syphilis were more likely to a show decrease in TWB reactivity than patients with latent symptoms who had been treated previously. As a diagnostic indicator of syphilis, the 17-kDa antigen was found to have the best combined attributes of sensitivity and specificity. Although, the highly specific 44.5 kDal and 24 kDal bands were often redundant as diagnostic indicators they are useful for the interpretation of borderline results. In addition, absence of the highly sensitive 47 and 15.5 kDa indicators should be useful in resolving some problem diagnoses.
Cytokines are a group of low molecular weight glycoproteins important in cellular signaling for various responses such as activation and proliferation. They separate the cellular responses into Th1 and Th2 pathways, where each pathway releases its own cytokine group. Interleukins are an important section of the cytokine group and consist of a number of members with their respective receptors such as interleukin-2 and interleukin-2 receptor (IL-2 and IL-2R, respectively). In this study, a soluble interleukin-2 receptor alpha (sIL-2R alpha) sandwich ELISA was developed and tested with different samples. This method was compared with other mono- and polyclonal antibodies that measure sIL-2R alpha molecule using the same subjects and recombinant sIL-2R alpha. The results showed that different antibody combinations measure different epitopes on the receptor molecule.
Chronic Fatigue Immune Dysfunction Syndrome (CFIDS) is a disorder characterized by debilitating fatigue associated with immunological abnormalities and cognitive impairments. The recently cloned RNase L Inhibitor (RLI) gene encodes a specific protein which is believed to regulate 2-5A synthetase and RNase L activity via the formation of a latent heterodimeric protein complex. In the present study, we investigated the levels of 2-5A synthetase, RNase L and RLI in patients with CFIDS as compared to healthy controls. Quantitative Competitive PCR (Q/C PCR) analysis showed a statistically significant decrease in RLI mRNA present in the peripheral blood lymphocytes (PBL) of patients with CFIDS (n = 25, mean = 569, S.E = 154) as compared to RLI mRNA level present in peripheral blood lymphocytes (PBL) of healthy controls (n = 15, mean = 2296, S.E = 506; p < 0.0001). The decrease in RLI mRNA in CFIDS individuals correlated directly with RLI and RLI: RNase L protein ratio while showing an inverse relationship to the 2-5A synthetase and RNase L activity. This RLI mRNA and protein deficiency in CFIDS patients may explain the increase in activity of RNase L found in CFIDS patients. The unidirectional decrease in RLI message and protein levels in CFIDS individuals may contribute to the destabilization of the latent RLI:RNase L heterodimeric protein complex, resulting in the excessive activation of RNase L shown in this study. The increased activation of RNase L may result in an increased cellular RNA turnover and subsequent inhibition of protein synthesis; thus resulting in general fatigue, myalgia muscle weakness and other symptomatologies shown in CFIDS patients. Furthermore, this data supports the hypothesis that the antiviral 2-5 oligoadenylate synthetase (2-5OAS) overexpression in individuals with CFIDS correlates with an increase in RNase L activity and with a decrease in RNase L inhibitor.
In this study time for initial assessment of monthly intravenous cyclophosphamide (CP) pulse therapy is discussed for a better outcome with less complications. Eleven patients with lupus nephritis (LN) resistant to conventional therapy (serum creatinine level < or = 2.7 mg/dl) were given 500 mg/m2 of CP 7-9 times with an interval of one month. Urinary protein (Up) decreased in all patients after 3 courses of CP pulse therapy and kept similar levels thereafter. In one group of patients (n = 7), Up decreased to < 2 g/day after 3 courses, while in the other group (n = 4), it did not decrease to < 4 g/day. Creatinine clearance increased by 0-100% in the former group, while it decreased by 5-20% in the latter group after 6-9 courses. Renal function of the patients with insufficient response after 3 courses tended to show no further improvement or worsened thereafter, although Up decreased during CP pulse therapy. A relatively small dose of CP (500 mg/m2) pulse therapy was useful in most LN patients regardless of the renal histology and it was thought important to assess its effects after 3 courses for a prediction of the clinical course. Modification of the protocol at that time might be necessary in regard to dose or interval of CP administration especially for patients with insufficient outcome.
Cytokines are a group of low molecular weight glycoproteins important in cellular signaling for various responses such as activation and proliferation. They separate the cellular responses into Th1 and Th2 pathways, where each pathway releases its own cytokine group. Interleukins are an important section of the cytokine group, and consist of a number of members with their respective receptors such as interleukin-2 and interleukin-2 receptor (IL-2 and IL-2R, respectively). In this study, a soluble interleukin-2 receptor (sIL-2R alpha) sandwich ELISA was developed and tested with different samples. This method was compared with commercial test kits that measure sIL-2R alpha molecule. The results showed that different kits measure different epitopes on this molecule.
The aim of this study was to analyse the lymphocyte subpopulations in the peripheral blood of HIV-1-infected adults to compare them with four patients with acute EBV infection. Lymphocyte subsets in 15 healthy controls, 40 HIV-1-infected adults and 4 EBV-infected patients with infectious mononucleosis were analysed by flow cytometry. The immunophenotyping of HIV-1-infected patients in different stages of disease showed a significant reduction in the percentage and absolute count of CD4+ T-lymphocytes, significantly increased percentage of CD8+ T-lymphocytes, inverted CD4/CD8 ratio and an increase in the expression of activation marker HLA-DR compared to controls. The immuno-phenotyping profiles of HIV and EBV infection share some similarities as they both result in the decreased percentage of CD4+ T-lymphocytes, increased CD8+ T-lymphocytes and an inverted CD4/CD8 ratio. Patients with HIV infection could be distinguished from patients with EBV infection by the absolute lymphocytosis and increased expression of HLA-DR seen in the patients with infectious mononucleosis. In conclusion, both HIV-1 and EBV profoundly change the distribution of lymphocyte subpopulations in the peripheral blood. It is our opinion that flow cytometry could be an aid in the rapid distinguishing of patients with suspected primary HIV-1 infection from those with infectious mononucleosis (before serology data are available).
We have previously reported a CD3+ CD4+ CD8- T cell line, J-2R which specifically recognized J558 individual idiotope (IdI) of anti-alpha (1-->3) dextran antibodies in an I-E(d) restricted manner. The J-2R proliferated in response to J558 IdI-derived peptides; however, the ability of the peptides to evoke the proliferation of J-2R was different. In the present study, we investigated the interaction between J558 IdI-derived peptides and I-E(d) molecules in competition experiments using a M104E IdI-derived peptide, M88-105. The M88-105 inhibited the proliferation of J-2R induced by J558 IdI-derived peptides. Furthermore, the proliferation induced by the peptides J92-109 and J96-105 was inhibited by the M88-105 at much lower inhibitor/antigenic peptide ratios, compared to the proliferation induced by the J88-105. Thus, shift of the framework to C-terminus and deletion of N-terminus amino acid residues from the 18-mer peptide J88-105 made the peptides more susceptible to the inhibition by the M88-105. Sequencing of the J-2R T cell receptor (TcR) revealed that J-2R used TcR, V alpha 1, J alpha 44; V beta 15, D beta 1, J beta 1.5. These results suggest that the peptides, J88-105, J92-109 and J96-105, directly bind to I-E(d) molecules, and that the capacity of J558 IdI-derived peptides to activate J-2R depends on the affinity to the I-E(d) molecules.
Phenotypic analysis of peripheral blood mononuclear cells from uterine cervix cancer patients, with increased natural killer cell activity, treated with radiation therapy was carried out. An increase in the percentage of CD56+ cells was observed in 5 out of 7 patients. When the expression of CD69, a phenotypic marker of cellular activation, was analyzed in 6 patients, an increase was observed in 4 of them. No direct correlation between cytolytic activity and the levels of CD56+ or CD69+ cells were observed. After 72 hr, an increased expression of CD56 was observed in 3 patients and a similar picture was seen at the same time following activation with IL-2 or IFN.
The authors present a case of a patient who developed recurrent bacterial upper respiratory and pulmonary infections and marked hypogammaglobulinemia with a gradual decrease of serum IgG, IgA and IgM some months after acute Epstein-Barr virus infection. Test for identification of lymphocyte subpopulation showed increased CD8+ T-cells with a surface phenotype (CD8+, CD57+, HLA-DR+) characteristic of virus-induced, activated cytotoxic cells. Viral investigations showed a positive anti-EBNA titer, an IgG titer anti-VCA of 1:40, a negative IgG titer anti-EA and human immunodeficiency virus negativity. The authors conclude that these clinical features are indicative of possible common variable immunodeficiency following Epstein-Barr virus infection.
We have previously reported a CD3+ CD4+ CD8- T cell line, J-2R which specifically recognized J558 individual idiotope (IdI) of anti-alpha (1-->3) dextran antibodies in an I-E(d) restricted manner. The J-2R proliferated in response to J558 IdI-derived peptides; however, the ability of the peptides to evoke the proliferation of J-2R was different. In the present study, we investigated the interaction between J558 IdI-derived peptides and I-E(d) molecules in competition experiments using a M104E IdI-derived peptide, M88-105. The M88-105 inhibited the proliferation of J-2R induced by J558 IdI-derived peptides. Furthermore, the proliferation induced by the peptides J92-109 and J96-105 was inhibited by the M88-105 at much lower inhibitor/antigenic peptide ratios, compared to the proliferation induced by the J88-105. Thus, shift of the framework to C-terminus and deletion of N-terminus amino acid residues from the 18-mer peptide J88-105 made the peptides more susceptible to the inhibition by the M88-105. Sequencing of the J-2R T cell receptor (TcR) revealed that J-2R used TcR, V alpha 1, J alpha 44; V beta 15, D beta 1, J beta 1.5. These results suggest that the peptides, J88-105, J92-109 and J96-105, directly bind to I-E(d) molecules, and that the capacity of J558 IdI-derived peptides to activate J-2R depends on the affinity to the I-E(d) molecules.
