In this report, we describe a short peptide, containing a T helper- and a B-cell epitope, located in the Gag protein of the caprine arthritis encephalitis virus (CAEV). This T-cell epitope is capable ...of inducing a robust T-cell proliferative response in vaccinated goats with different genetic backgrounds and to provide help for a strong antibody response to the B-cell epitope, indicating that it may function as a universal antigen-carrier for goat vaccines. The primary immune response of goats homozygous for MHC class I and II genes showed an MHC-dependent partitioning in rapid-high and slow-low responses, whereas the memory immune response was strong in both groups, demonstrating that a vaccine based on this immunodominant T helper epitope is capable to overcome genetic differences.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
A partir do século XVI, encontram-se nos textos médicos imagens de nascituros ou fetos. Observadas em seqüência cronológica, aquelas ilustrações atestam a passagem de uma idéia “afetiva” da formação ...da vida no ventre materno a uma imagem científica e “verossímil”. Por muito tempo, depois dos estudos de Leonardo sobre o feto, continuam sendo desenhados fetos fantásticos, uma vez que o único “estudo” possível sobre o feto era aquele de um cadáver. Estudar a morte para conhecer a vida esteve, durante séculos, em contradição com a mentalidade difundida. Realmente, até o século XVIII o olhar médico se deteve aquém do ventre grávido, respeitando o segredo queenvolvia a gestação. Somente no século XIX o pensamento científico separará o nascituro da mãe: os fetos começam a ser desenhados em um fundo branco ao invés de dentro do útero. O habitat não é mais a simbiose materna, mas um livro ou um atlas, onde o feto começará a ser pensado quase como uma espécie em si, e não mais como um bebê que é esperado.
Institute of Veterinary Virology, University of Berne, Länggass-Str. 122, CH-3012 Berne, Switzerland 1
Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington ...State University, Pullman, Washington 99164-7040, USA 2
Génétique des Virus (ICGM-CNRS UPR 0415), Institut Cochin de Génétique moléculaire, 75014 Paris, France 3
Author for correspondence: Giuseppe Bertoni. Fax +41 31 631 25 34. e-mail bertoni{at}ivv.unibe.ch
Goats infected with caprine arthritisencephalitis virus (CAEV) develop high titres of antibodies to Env. Not only is no consistent neutralizing response found but anti-Env antibodies have even been associated with disease in infected goats. To identify the continuous antigenic determinants involved in this atypical anti-Env response, we mapped CAEV-CO Env by screening an epitope expression library with infected goat sera. In addition to the four previously described epitopes, seven novel antigenic sites were identified, of which five were located on the surface (SU) and two in the transmembrane (TM) subunits of Env. The SU antibody-binding domains located in the variable regions of the C-terminal part of the molecule (SU3 to SU5) showed the strongest reactivity and induced a rapid seroconversion in six experimentally infected goats. However, the response to these immunodominant epitopes did not appear to be associated with any neutralizing activity. The pattern of serum reactivity of naturally infected goats with these epitopes was restricted, suggesting a type-specific reaction. Interestingly, the reactivity of peptides representing SU5 sequences derived from CAEV field isolates varied with the geographical and/or breeding origin of the animals. This suggests that peptides corresponding to the immunodominant SU epitopes may well be useful in the serotyping of CAEV isolates. Furthermore, the identification of the CAEV Env epitopes will permit us to functionally dissect the antibody response and to address the role of anti-Env antibodies either in the protection from or in the pathogenesis of CAEV infection.
The first Dominique Dormont International Conference on "Viral and host determinantsof HCV, HCMV, and HIV infections "was held in Paris, Val-de-Grâce, on December 3-4, 2004. The following is a ...summary of the scientific sessions of this meeting (http://www.congres-evenement.fr/ddormont).
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
To study the progression of HIV-1 infection and coreceptor usages in Central African Republic, clinical data, plasma viral load, and coreceptor usage of sequential HIV-1 isolates were analyzed in a ...seroincident prospective cohort (PRIMOCA). Twenty-three HIV-1 infected individuals from the Central African Armed Forces were followed from 1995 to 2000. Viruses were isolated from 17 patients at various time points after seroconversion and their coreceptor usage was examined using GHOST cells expressing CD4 and one of the HIV-1 chemokine coreceptors CCR5, CXCR4, BOB/GPR15, and Bonzo/STRL33/CXCR6. Eleven patients died from AIDS. Eight of them died between 2 and 5 years after seroconversion, after a brief symptomatic stage. Patients who rapidly progressed to AIDS and death displayed the highest viral loads after seroconversion. All isolates obtained soon after seroconversion used CCR5, albeit, in some cases, CXCR4, BOB, or Bonzo were also used. Most isolates remained R5 (59 out of 61 isolates), although viruses using CXCR4 appeared in some cases of progression to AIDS. In several cases, a broad tropism was observed during the course of infection, with a frequent usage of BOB and Bonzo in addition to CCR5. Rapid progression to disease and short survival time among Central African HIV-1 patients appear more frequent than those reported in industrialized countries. Viral coreceptor used was mainly CCR5, but, interestingly, a large part of isolates also used BOB and Bonzo. However, there was no strict correlation between the clinical outcome and extended viral tropism.
High titers of antibodies to caprine arthritis-encephalitis virus (CAEV) envelope (Env) glycoproteins are found in infected goats developing a progressive arthritis. In order to identify linear B ...epitopes of the CAEV Env, which may be involved in the immunopathology of arthritis, we constructed a lambda gt11 Env expression library. By combining library screening with sera from naturally infected Swiss goats with an enzyme immunoassay with overlapping peptides (pepscan), four group-specific epitopes could be precisely defined in the transmembrane envelope proteins: TM1 to TM4, including a conserved structure (TM3) that corresponds to the immunodominant epitope of human immunodeficiency virus type 1 and other lentiviruses. A panel of 190 CAEV naturally infected goat serum samples. obtained from animals with defined clinical status, was tested for reactivity to synthetic peptides corresponding to the TM epitopes in an enzyme-linked immunosorbent assay. Antibody reactivity to two epitopes was highly associated (TM3, P = 0.062, and TM4, P 0.001) with the presence of clinically detectable arthritis. Such an association is absent for anti-Gag antibody. Antibodies to the immunodominant structures of the TM glyeoprotein could thus have an important role in the immunopathogenic process leading to disease
This report describes a method for the production of murine monoclonal antibodies (MAbs) against cellular antigens preserved during formol fixation and paraffin embedding of human tissues in an ...attempt to select markers that would be useful in immunopathology. Hybridomas were prepared using spleen cells from mice immunized with cell suspensions obtained from formalin-fixed paraffin block sections of a human breast carcinoma. A monoclonal antibody 83 D4 was selected, which was reactive with paraffin embedded breast carcinoma tissues, but not with normal breast. The reactive antigen has a high molecular weight (400-1000 kD) and was detected on the cell surface of live human breast cancer cell lines and on frozen tissues sections. These results demonstrate that the MAb 83 D4 identifies a native breast tumor associated epitope conserved during tissue fixation and embedding and could be used as an immunohistochemical marker.
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