34 research outputs found

    What is the influence of vaccination’s routes on the regression of tumors located at mucosal sites?

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    Tumor-regressions following tumor-associated-antigen vaccination in animal models contrast with the limited clinical outcomes in cancer patients. Most animal studies however used subcutaneous-tumor-models and questions arise as whether these are relevant for tumors growing in mucosae; whether specific mucosal-homing instructions are required; and how this may be influenced by the tumor

    Vaccination against human papillomavirus in Switzerland: simulation of the impact on infection rates

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    Objectives: Human papillomavirus (HPV) is a sexually transmitted infection of particular interest because of its high prevalence rate and strong causal association with cervical cancer. Two prophylactic vaccines have been developed and different countries have made or will soon make recommendations for the vaccination of girls. Even if there is a consensus to recommend a vaccination before the beginning of sexual activity, there are, however, large discrepancies between countries concerning the perceived usefulness of a catch-up procedure and of boosters. The main objective of this article is to simulate the impact on different vaccination policies upon the mid- and long-term HPV 16/18 age-specific infection rates. Methods: We developed an epidemiological model based on the susceptible-infective-recovered approach using Swiss data. The mid- and long-term impact of different vaccination scenarios was then compared. Results: The generalization of a catch-up procedure is always beneficial, whatever its extent. Moreover, pending on the length of the protection offered by the vaccine, boosters will also be very useful. Conclusions: To be really effective, a vaccination campaign against HPV infection should at least include a catch-up to early reach a drop in HPV 16/18 prevalence, and maybe boosters. Otherwise, the protection insured for women in their 20s could be lower than expected, resulting in higher risks to later develop cervical cance

    Specific Antibody Levels at the Cervix During the Menstrual Cycle of Women Vaccinated With Human Papillomavirus 16 Virus-Like Particles

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    Background: In early-phase trials, a human papillomavirus 16 (HPV16) virus-like particle (VLP) vaccine has been shown to be well tolerated, immunogenic, and protective against HPV16 in women, most of whom were taking oral contraceptives. Previous studies have not determined whether HPV immunization results in specific antibody levels in the human genital tract or whether these levels might vary during contraceptive or ovulatory cycles. Therefore, we determined the levels of total and specific antibodies in the cervical secretions of women who had been immunized with HPV16 VLPs and examined the influence of the menstrual cycle and oral contraceptive use on these levels. Methods: Two groups of women were immunized, seven who were taking oral contraceptives and 11 who were ovulating. After seroconversion, serum and cervical secretions were collected twice weekly for 5 weeks. Total immunoglobulins (IgG and IgA) and vaccine-specific IgGs were determined by enzyme-linked immunosorbent assay. Nonparametric statistical analyses were used to determine the statistical significance of differences in IgG levels between groups, and correlations between serum- and cervical-specific IgG levels were determined by the Spearman correlation coefficient. Results: All participants developed detectable titers of anti-HPV16 VLP IgGs in their cervical secretions after immunization. The cervical titers of specific IgG and total IgGs and IgAs among participants in the contraceptive group were relatively constant throughout the contraceptive cycle. In contrast, the cervical titers of specific IgG and total IgGs and IgAs among participants in the ovulatory group varied during the menstrual cycle, being highest during the proliferative phase, decreasing approximately ninefold around ovulation, and increasing approximately threefold during the luteal phase. Serum- and cervical-specific IgG levels were correlated (r = .86) in women in the contraceptive group but not in women in the ovulatory group (r = .27). Conclusions: The relatively high titer of anti-HPV16 antibodies at the cervix is promising in terms of vaccine efficacy; however, the decrease in antibody titer around ovulation raises the possibility that the HPV16 VLP vaccine might be less effective during the peri-ovulatory phas

    RESPONSABILIDADE SOCIAL: FATORES CULTURAIS PERCEBIDOS PELOS ATORES DA ORGANIZAÇÃO

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    Responsabilidade social e sustentabilidade são temas discutidos atualmente, devido ao impacto que as organizações geram nas comunidades nas quais estão inseridas. A cultura organizacional pode ser refletida pelas ações da organização em relação ao tema, com o compartilhamento de experiências, decisões, histórias e padrões de comportamento que são apreendidas, transmitidas e posteriormente modificadas. Este estudo tem por objetivo analisar a relação entre cultura e responsabilidade social por meio da percepção dos atores organizacionais, em uma empresa do ramo de confecção de pijamas e lingerie de Brusque, Santa Catarina. Realizou-se pesquisa quantitativa, descritiva transversal, do tipo survey. Para a coleta de dados utilizou-se questionário com 40 questões estruturado em nove dimensões de cultura que se relacionam com responsabilidade social, elaborado a partir dos estudos de Machado e Vasconcelos (2005; 2007), Machado, Lehmann e Araújo (2008) e Machado et al. (2008; 2009). A população é formada por 144 funcionários, sendo a amostra composta por 80 respondentes representantes de todas as funções existentes na empresa. Para a análise utilizou-se a análise de frequência, alfa de Cronbach e correlação de Pearson. Os resultados indicam investimentos da organização em aspectos concretos da cultura, porém quanto à Responsabilidade Social, a cultura está em fase de construção

    ILC2-modulated T cell-to-MDSC balance is associated with bladder cancer recurrence.

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    Non-muscle-invasive bladder cancer (NMIBC) is a highly recurrent tumor despite intravesical immunotherapy instillation with the bacillus Calmette-Guérin (BCG) vaccine. In a prospective longitudinal study, we took advantage of BCG instillations, which increase local immune infiltration, to characterize immune cell populations in the urine of patients with NMIBC as a surrogate for the bladder tumor microenvironment. We observed an infiltration of neutrophils, T cells, monocytic myeloid-derived suppressor cells (M-MDSCs), and group 2 innate lymphoid cells (ILC2). Notably, patients with a T cell-to-MDSC ratio of less than 1 showed dramatically lower recurrence-free survival than did patients with a ratio of greater than 1. Analysis of early and later time points indicated that this patient dichotomy existed prior to BCG treatment. ILC2 frequency was associated with detectable IL-13 in the urine and correlated with the level of recruited M-MDSCs, which highly expressed IL-13 receptor α1. In vitro, ILC2 were increased and potently expressed IL-13 in the presence of BCG or tumor cells. IL-13 induced the preferential recruitment and suppressive function of monocytes. Thus, the T cell-to-MDSC balance, associated with a skewing toward type 2 immunity, may predict bladder tumor recurrence and influence the mortality of patients with muscle-invasive cancer. Moreover, these results underline the ILC2/IL-13 axis as a targetable pathway to curtail the M-MDSC compartment and improve bladder cancer treatment

    Monitoring of Vaccine-Specific Gamma Interferon Induction in Genital Mucosa of Mice by Real-Time Reverse Transcription-PCR▿

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    Monitoring of T-cell responses in genital mucosa has remained a major challenge because of the absence of lymphoid aggregates and the low abundance of T cells. Here we have adapted to genital tissue a sensitive real-time reverse transcription-PCR (TaqMan) method to measure induction of gamma interferon (IFN-γ) mRNA transcription after 3 h of antigen-specific activation of CD8 T cells. For this purpose, we vaccinated C57BL/6 mice subcutaneously with human papillomavirus type 16 L1 virus-like particles and monitored the induction of CD8 T cells specific to the L1165-173 H-2Db-restricted epitope. Comparison of the responses induced in peripheral blood mononuclear cells and lymph nodes (LN) by L1-specific IFN-γ enzyme-linked immunospot assay and TaqMan determination of the relative increase in L1-specific IFN-γ mRNA induction normalized to the content of CD8b mRNA showed a significant correlation, despite the difference in the readouts. Most of the cervicovaginal tissues could be analyzed by the TaqMan method if normalization to glyceraldehyde-3-phosphate dehydrogenase mRNA was used and a significant L1-specific IFN-γ induction was found in one-third of the immunized mice. This local response did not correlate with the immune responses measured in the periphery, with the exception of the sacral LN, an LN draining the genital mucosa, where a significant correlation was found. Our data show that the TaqMan method is sensitive enough to detect antigen-specific CD8 T-cell responses in the genital mucosa of individual mice, and this may contribute to elaborate effective vaccines against genital pathogens

    A Murine Genital-Challenge Model Is a Sensitive Measure of Protective Antibodies against Human Papillomavirus Infection ▿

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    The available virus-like particle (VLP)-based prophylactic vaccines against specific human papillomavirus (HPV) types afford close to 100% protection against the type-associated lesions and disease. Based on papillomavirus animal models, it is likely that protection against genital lesions in humans is mediated by HPV type-restricted neutralizing antibodies that transudate or exudate at the sites of genital infection. However, a correlate of protection was not established in the clinical trials because few disease cases occurred, and true incident infection could not be reliably distinguished from the emergence or reactivation of prevalent infection. In addition, the current assays for measuring vaccine-induced antibodies, even the gold standard HPV pseudovirion (PsV) in vitro neutralization assay, may not be sensitive enough to measure the minimum level of antibodies needed for protection. Here, we characterize the recently developed model of genital challenge with HPV PsV and determine the minimal amounts of VLP-induced neutralizing antibodies that can afford protection from genital infection in vivo after transfer into recipient mice. Our data show that serum antibody levels >100-fold lower than those detectable by in vitro PsV neutralization assays are sufficient to confer protection against an HPV PsV genital infection in this model. The results clearly demonstrate that, remarkably, the in vivo assay is substantially more sensitive than in vitro PsV neutralization and thus may be better suited for studies to establish correlates of protection

    Improved Efficiency of a Salmonella-Based Vaccine against Human Papillomavirus Type 16 Virus-Like Particles Achieved by Using a Codon-Optimized Version of L1

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    Cervical cancer results from cervical infection by human papillomaviruses (HPVs), especially HPV16. An effective vaccine against these HPVs is expected to have a dramatic impact on the incidence of this cancer and its precursor lesions. The leading candidate, a subunit prophylactic HPV virus-like particle (VLP) vaccine, can protect women from HPV infection. An alternative improved vaccine that avoids parenteral injection, that is efficient with a single dose, and that induces mucosal immunity might greatly facilitate vaccine implementation in different settings. In this study, we have constructed a new generation of recombinant Salmonella organisms that assemble HPV16 VLPs and induce high titers of neutralizing antibodies in mice after a single nasal or oral immunization with live bacteria. This was achieved through the expression of a HPV16 L1 capsid gene whose codon usage was optimized to fit with the most frequently used codons in Salmonella. Interestingly, the high immunogenicity of the new recombinant bacteria did not correlate with an increased expression of L1 VLPs but with a greater stability of the L1-expressing plasmid in vitro and in vivo in absence of antibiotic selection. Anti-HPV16 humoral and neutralizing responses were also observed with different Salmonella enterica serovar Typhimurium strains whose attenuating deletions have already been shown to be safe after oral vaccination of humans. Thus, our findings are a promising improvement toward a vaccine strain that could be tested in human volunteers
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