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ROLE OF THE MUCOSAE-ASSOCIATED EPITHELIAL CHEMOKINE (MEC/CCL28) IN THE MODULATION OF THE IMMUNE RESPONSE AGAINST VIRAL INFECTIONS
Get PDFSecretory immunity is the main line of defence against mucosal infections as it can provide pathogen blocking
secretory IgA at the mucosal surface. CCL28 is a chemokine that binds to CCR3 and CCR10 and
potently recruits IgA-secreting plasma cells (IgA-ASCs) in the mucosal lamina propria. Virus-like particles
(VLPs) are a novel vaccine approach based on non-pathogenic particles that mimic the structure of authentic
virus particles. Immunogenicity of vaccines can be improved by the use of chemokine molecular adjuvants.
Here we propose experimental strategies for evaluating CCL28 immunomodulatory effects in mice after
vaccination with VLPs of HIV-1IIIB, Influenza A virus (H7N1) and HPV-16 for potential future use of the
chemokine as an adjuvant in the development of preventive vaccines against mucosal infections.
HIV1IIIB-, H7N1- and HPV16-VLPs were produced in collaboration with the Ruhr-Bochum University, the
University of Montpellier and the German Research Cancer Centre of Heidelbergh, respectively. Inbred
female Balb/c mice were randomized to receive HIV1IIIB-VLPs or H7N1-VLPs or HPV16-VLPs in the
presence or absence of the murine CCL28-expressing plasmid on days 0 and 14. Mice were euthanized on
day 28. The murine CCL19 expression vector was used as negative control, as this chemokine binds to
CCR7 receptor. HIV1IIIB-VLPs, HPV16-VLPs and CCL28- and CCL19-expressing plasmids were
administrated intramuscularly; H7N1-VLPs were administrated intraperitoneally. Blood samples and vaginal
secretions were collected by standard methods on days 0, 14 and 28. Saliva samples of H7N1-VLPs treated
mice were collected on days 0, 14 and 28 after intraperitoneal injection of carbachol to induce mice drooling.
Bronchoalveolar lavages were collected on day 28 by insertion into the trachea of a blunt animal-feeding
needle and repeated cycles of injection and aspiration of PBS. Tissues obtained from the spleen, colon,
lungs and the uterine cervix were collected on day 28 to obtain the lymphocyte-enriched cell population for
cell culture assays and to evaluate IgA-plasma cell distribution at the mucosal level by
immunohistochemistry analyses. CCR3 and CCR10 surface receptors were evaluated on circulating
splenocytes by flow cytometry. Th1- and Th2-type cytokine production was evaluated in the supernatants
from cultivated splenocytes and mucosal T-cells after ex vivo re-stimulation with recombinant HIV-1IIIB gp120
or hemagglutinin (HA) from Influenza virus A H7N1 or HPV-1 L1 protein. Antigen-specific IgG and IgA were
measured in sera and mucosal secretions by an ELISA method based on recombinant HIV-1IIIB gp120, HA
from Influenza A virus H7N1 and HPV-16 L1 protein. Neutralizing activity of both systemic and mucosal
antibodies was assessed as well. Finally, CCL28-mediated recruitment of IgA-ASCs at mucosal sites was
evaluated by immunohistochemistry analyses of tissues obtained from the mucosa-associated lymphoid
tissue (MALT).
Results presented herein show a significant increase in the percentage and in the mean fluorescence
intensity (MFI) of CCR3 and CCR10 on CD19+ splenocytes in VLP-CCL28 mice compared to VLP-CCL19 or
VLP alone or CCL28 alone or CCL19 alone or saline mice. Antigen-specific production of Th1-type (IFN-gamma)
and Th2-type (IL-4 and IL-5) cytokines was significantly augmented in splenocytes and mucosal tissues of
VLP-CCL28 mice compared to VLP-CCL19 or VLP alone mice. Total IgA levels were significantly increased
compared to baseline values in vaginal secretions of HIV1IIIB-VLP-CCL28 and HPV16-VLP-CCL28 mice, and
in saliva samples, BALs and lung homogenates of H7N1-VLP-CCL28 mice on day 28. Antigen-specific IgA
were similarly augmented in vaginal secretions of HIV1IIIB-VLP-CCL28 and HPV16-VLP-CCL28 mice and in
lungs of H7N1-VLP treated mice. Data were confirmed by the observation that the neutralization ability of
both immune sera and mucosal secretions was significantly up-regulated in mice receiving CCL28. Finally,
results presented here indicate that immunization on the presence of the CCL28-expressing plasmid
significantly increases the quantity of mucosal IgA-ASCs in the rectum of HIV1IIIB-VLP-receiving mice, in the
lungs of H7N1-VLP-receiving mice and in the uterine cervix of HPV16-VLP-receiving mice.
CCL28 mediates mucosal immunity; the effect is reproducible using this chemokine as an adjuvant in mice
immunized with VLPs of mucosally transmitted viruses. CCL28-containing adjuvants should be considered in
the development of vaccines against HIV-1, Influenza A virus and HPV to prevent infection of mucosal sites
via modulation of mucosal IgA. Nevertheless, the efficacy evaluation of CCL28 adjuvanticity requires further
experiments to define immune correlates of mucosal responses to vaccination with VLPs in combination with
chemokine adjuvants
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Maraviroc reduces arterial stiffness in PI-treated HIV-infected patients
Get PDFThe Delta 32-CCR5 deletion of the CCR5 receptor is protective toward coronary artery pathology and myocardial infarction. Maraviroc (MVC), a CCR5 antagonist, was recently introduced in the therapy of HIV infection; we evaluated whether this drug could modulate the atherosclerotic burden in aviremic PI-treated HIV-positive individuals who underwent MVC intensification. Thus, the effect of MVC on intima media thickness, arterial stiffness, metabolic parameters, pro-inflammatory cytokines, endothelial dysfunction, and microbial traslocation markers was analyzed in 6 aviremic PI-treated HIV-positive individuals and were compared to those obtained in 9 additional aviremic PI-treated subjects that were enrolled retrospectively from our outpatients cohort. MVC intensification resulted in a significant reduction in intima media thickness, pulse wave velocity and triglycerides compared to baseline. Notably, MVC was also associated with a significant reduction of IL-6, microbial translocation indexes, sICAM and sVCAM; these changes were maintained throughout the 6 months of MVC intensification. No significant modifications were observed in CD4 counts, HIV viral load, and cholesterolemia. Results herein support a role of CCR5 antagonists in reducing the cardiovascular risk in HIV-infection. The hampering of inflammation, microbial translocation and the improvement of endothelial function could justify the protective role of CCR5 antagonists on atherosclerotic burden
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Efficacy of HPV vaccination in HIV+ adolescents and young adults for the induction of strong HPV-specific humoral and cell mediated immune responses
No full textEfficacy of HPV vaccination in HIV+ adolescents and young adults for the induction of strong HPV-specific humoral and cell mediated immune responses
Dendritic Cell Labelling with Paramagnetic Nanoparticles, 111In-Oxine and PKH26 for In Vivo Magnetic Resonance, SPECT and Optical Imaging of their Migration
No full textAim: The aim of this study is the development and the evaluation of a tumour-specific DC vaccine in a transgenic murine model of breast cancer (MMTV-v-Ha-Ras). DC labelling with commercial paramagnetic nanoparticles (MNPs, Endorem®), 111In-Oxine or PKH26 will permit to study their distribution and migration to local lymph-nodes by MRI, SPECT or optical imaging, respectively. Methods: Total bone marrow cells were extracted from wt mice. DC differentiation was studied by flow cytometry; at the 6th day of culture DCs were labelled with commercial MNPs, 111In-Oxine or PKH26. Dose response and kinetic of labelling studies were performed. Labelling efficiency was evaluated. iDCs were loaded with tumour antigens and maturation was monitored by flow cytometry. Stimulatory activity of antigen-loaded DCs was evaluated by T-cell proliferation and IFN-γ production by T cells; DC migration was evaluated in the presence of 6Ckine, MIP-3β, MIP-1α and MIP-1β. MNP-labelled DCs, loaded with tumour antigens were injected into the footpad of transgenic tumour bearing mice. Perl’s staining of the draining lymph nodes was carried out to evaluate DC migration. Results: FACS analyses identified the best time point to perform DC labelling. Results showed that labelling efficiency with MNPs was proportional to the medium iron content and to the incubation time (ideal conditions 200 μg Fe/ml, for 16h with 85% efficiency) as confirmed by relaxometric assay. Labelling with MNPs did not affect DC immune-phenotype or functionality as demonstrated by CD86 and CD83 expression levels, and by LPS induction of labelled DC maturation. Labelling with 30 and 60 μCi of 111In-Oxine resulted in a 75% and 72% efficiency, respectively. Concurrent DC labelling with PKH26 and 30 μCi of 111In-Oxine did not impair labelling efficiency. DC vitality was not highly affected by all the labelling procedures. Antigen-loaded DCs induced T-cell proliferation and INF-γ production. Migration assays showed that antigen-loaded DCs were able to migrate in the presence of stimulatory chemokines (6Ckine and MIP3β). Perl’s staining of lymph node sections after in vivo injection of labelled DCs loaded with the antigens, showed the presence of iron within the node, indicating that mature and labelled DCs migrate in vivo from the site of injection to the draining lymph node. Conclusions: Cell labelling with different probes for multimodal imaging of DCs will permit to overcome the limitation of the single imaging techniques and to in vivo visualise their migration and limph-node localisation, shedding light on the fundamental parameters responsible for the anti-neoplasic efficacy
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