99 resultados para nonhuman primate pathology
Resumo:
UNLABELLED: We compared the HIV-1-specific cellular and humoral immune responses elicited in rhesus macaques immunized with two poxvirus vectors (NYVAC and ALVAC) expressing the same HIV-1 antigens from clade C, Env gp140 as a trimeric cell-released protein and a Gag-Pol-Nef polyprotein as Gag-induced virus-like particles (VLPs) (referred to as NYVAC-C and ALVAC-C). The immunization protocol consisted of two doses of the corresponding poxvirus vector plus two doses of a combination of the poxvirus vector and a purified HIV-1 gp120 protein from clade C. This immunogenicity profile was also compared to that elicited by vaccine regimens consisting of two doses of the ALVAC vector expressing HIV-1 antigens from clades B/E (ALVAC-vCP1521) plus two doses of a combination of ALVAC-vCP1521 and HIV-1 gp120 protein from clades B/E (similar to the RV144 trial regimen) or clade C. The results showed that immunization of macaques with NYVAC-C stimulated at different times more potent HIV-1-specific CD4(+) T-cell responses and induced a trend toward higher-magnitude HIV-1-specific CD8(+) T-cell immune responses than did ALVAC-C. Furthermore, NYVAC-C induced a trend toward higher levels of binding IgG antibodies against clade C HIV-1 gp140, gp120, or murine leukemia virus (MuLV) gp70-scaffolded V1/V2 and toward best cross-clade-binding IgG responses against HIV-1 gp140 from clades A, B, and group M consensus, than did ALVAC-C. Of the linear binding IgG responses, most were directed against the V3 loop in all immunization groups. Additionally, NYVAC-C and ALVAC-C also induced similar levels of HIV-1-neutralizing antibodies and antibody-dependent cellular cytotoxicity (ADCC) responses. Interestingly, binding IgA antibody levels against HIV-1 gp120 or MuLV gp70-scaffolded V1/V2 were absent or very low in all immunization groups. Overall, these results provide a comprehensive survey of the immunogenicity of NYVAC versus ALVAC expressing HIV-1 antigens in nonhuman primates and indicate that NYVAC may represent an alternative candidate to ALVAC in the development of a future HIV-1 vaccine. IMPORTANCE: The finding of a safe and effective HIV/AIDS vaccine immunogen is one of the main research priorities. Here, we generated two poxvirus-based HIV vaccine candidates (NYVAC and ALVAC vectors) expressing the same clade C HIV-1 antigens in separate vectors, and we analyzed in nonhuman primates their immunogenicity profiles. The results showed that immunization with NYVAC-C induced a trend toward higher HIV-1-specific cellular and humoral immune responses than did ALVAC-C, indicating that this new NYVAC vector could be a novel optimized HIV/AIDS vaccine candidate for human clinical trials.
Resumo:
Waddlia chondrophila is a known bovine abortigenic Chlamydia-related bacterium that has been associated with adverse pregnancy outcomes in human. However, there is a lack of knowledge regarding how W. chondrophila infection spreads, its ability to elicit an immune response and induce pathology. A murine model of genital infection was developed to investigate the pathogenicity and immune response associated with a W. chondrophila infection. Genital inoculation of the bacterial agent resulted in a dose-dependent infection that spread to lumbar lymph nodes and successively to spleen and liver. Bacterial-induced pathology peaked on day 14, characterized by leukocyte infiltration (uterine horn, liver, and spleen), necrosis (liver) and extramedullary hematopoiesis (spleen). Immunohistochemistry demonstrated the presence of a large number of W. chondrophila in the spleen on day 14. Robust IgG titers were detected by day 14 and remained high until day 52. IgG isotypes consisted of high IgG2a, moderate IgG3 and no detectable IgG1, indicating a Th1-associated immune response. This study provides the first evidence that W. chondrophila genital infection is capable of inducing a systemic infection that spreads to major organs, induces uterus, spleen, and liver pathology and elicits a Th1-skewed humoral response. This new animal model will help our understanding of the mechanisms related to intracellular bacteria-induced miscarriages, the most frequent complication of pregnancy that affects one in four women.
Resumo:
Since Waddlia chondrophila is closely related to Chlamydia trachomatis, we hypothesise that W. chondrophila may also be associated with tubal factor infertility (TFI) in women, a major complication of chronic C. trachomatis infection. Five hundred twenty serum samples were tested for anti-Waddlia antibodies by ELISA. Among the 520 investigated women, a total number of 142 (27.3%) has had laparoscopic diagnosis performed, and were either classified TFI positive or negative. Presence of high titres of W. chondrophila antibodies was linked to TFI (p < 0.0001; OR: 7.5; 95% CI: 3.3-17). Moreover, antibody positivity to both W. chondrophila and C. trachomatis-MOMP was strongly associated with TFI (p < 0.0001; OR: 21; 95% CI: 3.8-12E1). This association was much stronger than the statistical association of C. trachomatis-MOMP antibodies only (p < 0.0001; OR: 7.1; 95% CI: 3.7-14), suggesting that co-infection with W. chondrophila and C. trachomatis may lead to more severe reproductive sequelae and immune responses than single infection with either Chlamydiales members.
Resumo:
Background: Endometriosis is an estrogen-dependent, pro-inflammatory, pro-angiogenic condition that affects 5 to 10% of women of reproductive age. Its defining feature is the presence of endometrium-like tissue in sites outside the uterine cavity, primarily on the pelvic peritoneum and ovaries. The main clinical features are chronic pain, pain during intercourse and infertility. In patients with endometriosis, inflammatory and immune responses, angiogenesis and apoptosis are altered in favour of the survival and replenishment of endometriotic tissue. These basic pathological processes depend on the excessive formation of estrogen and prostaglandins. Recently, new cellular and molecular mechanisms for the resolution of inflammation have been discovered, revealing key roles for lipid mediators such as lipoxins, resolvins and protectins. It is possible that disequilibrium in the expression of these molecules exists in endometriosis. Objective: To compare the expression of two proteins involved in the synthe sis and in the function of lipid mediators; the Arachidonate 15-lipoxygenase (ALOXI5), implicated in the synthesis of lipoxins A4 and B4 and the Formyl peptide receptor 1 (FPRLI), the specific receptor for Lipoxin A4 and B4, between women who suffer from endometriosis and a control group. We wish to demonstrate the cellular localisation of these two molecules and to investigate if their expression is alteted in this pathology. Methods and Materials Using immunohistochemistry we will compare ALOXI5 and FPRLI staining, in endometrium, normal peritoneum and endometriotic lesions. The samples are being collected in the department of Gynaecology and Obstetrics at the Centre Hospitalier Universitaire Lausanne (CHUV). Women attending the department for laparoscopic investigation of pain/infertility, suspected endometriosis or for a hysterectomy, are invited to participate. Approval of the ethics committee (Commission d'Ethique de la recherché clinique) was obtained in March 2009. Clinical samples will only be obtained from subjects having consented. Expected results and interpretation: No published studies investigating the expression of these two molecules in endometriotic lesions exist. A better understanding of the mechanisms underlying this disease will result in the development of new medical therapies and new diagnostic tests, with the aim of ameliorating the quality of life of endometriosis patients.
Resumo:
Communication is an essential element of good medical practice also in pathology. In contrast to technical or diagnostic skills, communication skills are not easy to define, teach, or assess. Rules almost do not exist. In this paper, which has a rather personal character and cannot be taken as a set of guidelines, important aspects of communication in pathology are explored. This includes what should be communicated to the pathologist on the pathology request form, communication between pathologists during internal (interpathologist) consultation, communication around frozen section diagnoses, modalities of communication of a final diagnosis, with whom and how critical and unexpected findings should be communicated, (in-)adequate routes of communication for pathology diagnoses, who will (or might) receive pathology reports, and what should be communicated and how in case of an error or a technical problem. An earlier more formal description of what the responsibilities are of a pathologist as communicator and as collaborator in a medical team is added in separate tables. The intention of the paper is to stimulate reflection and discussion rather than to formulate strict rules.