Les «lettres de protection» coptes

Etude des «lettres de protection» copte, notamment de leur formulaire. Réédition de trois documents.

Rapid immunological diagnosis of active tuberculosis, and differentiation from asymptomatic infection

info:eu-repo/semantics/nonPublished

HBHA-specific CD4+, CD8+ and CD4+CD25+FOXP3+ T cells as biomarkers for protection and disease in human tuberculosis

info:eu-repo/semantics/nonPublished

Genetic deficiency of the fourth component of complement :clinical, immunological and genetical studies in a further family. IXth International Complement Workshop

info:eu-repo/semantics/published

Different T cell memory in preadolescents after whole-cell or acellular pertussis vaccination.

To better understand vaccine-induced protection and its potential failure in light of recent whooping cough resurgence, we evaluated quantity as well as quality of memory T cell responses in B. pertussis-vaccinated preadolescent children. Using a technique based on flow cytometry to detect proliferation, cytokine production and phenotype of antigen-specific cells, we evaluated residual T cell memory in a cohort of preadolescents who received a whole-cell pertussis (wP; n=11) or an acellular pertussis vaccine (aP; n=13) during infancy, and with a median of 4 years elapsed from the last pertussis booster vaccine, which was aP for all children. We demonstrated that B. pertussis-specific memory T cells are detectable in the majority of preadolescent children several years after vaccination. CD4(+) and CD8(+) T cell proliferation in response to pertussis toxin and/or filamentous hemagglutinin was detected in 79% and 60% of the children respectively, and interferon-γ or tumor necrosis factor-α producing CD4(+) T cells were detected in 65% and 53% of the children respectively. Phenotyping of the responding cells showed that the majority of antigen-specific cells, whether defined by proliferation or cytokine production, were CD45RA(-)CCR7(-) effector memory T cells. Although the time since the last booster vaccine was significantly longer for wP-compared to aP-vaccinated children, their proliferation capacity in response to antigenic stimulation was comparable, and more children had a detectable cytokine response after wP- compared to aP-vaccination. This study supports at the immunological level recent epidemiological studies indicating that infant vaccination with wP induces longer lasting immunity than vaccination with aP-vaccines.

Immunological Signatures Identifying Different Stages of Latent Mycobacterium tuberculosis Infection and Discriminating Latent from Active Tuberculosis in Humans

Objectives: One third of the world population is considered latently infected with Mycobacterium tuberculosis(LTBI) and sterilizing this reservoir of bacteria that may reactivate is required for tuberculosis (TB) elimination. Thegroup of individuals with LTBI is heterogeneous with some of them being more at risk to develop TB disease thanothers. Improved diagnosis of subjects with LTBI is needed, allowing to differentiate subjects with LTBI from thosewith active TB, and to select among LTBI subjects those who are more at risk to develop active TB. We havecharacterized at the cellular level both the quantitative and qualitative T cell responses to different mycobacterialantigens in selected populations of infected subjects in order to identify new biomarkers that could help to identify M.tuberculosis-infected subjects and to stratify them in risk groups for reactivation of the infection.Methods: Lymphoblast frequencies and cytokine production (IFN-γ, TNF-α, IL-2) among CD4+ and CD8+ T cellswere analyzed by flow cytometry after in vitro stimulation with the latency antigen heparin-binding haemagglutinin(HBHA) or early-secreted antigen Target-6 (ESAT-6) of peripheral blood mononuclear cells from clinically wellcharacterized M. tuberculosis-infected humans (28 LTBI, 22 TB disease,12 controls). The LTBI group definedaccording to the Center for Disease Control guidelines was subdivided into QuantiFERON-TB Gold in-Tube (QFT)positive and negative subgroups.Results: Similar to TB patients, QFT+ LTBI subjects had higher proportions of HBHA-induced TNF-αsingle+ CD4+lymphocytes than QFT- LTBI subjects (p<0.05). Compared to LTBI subjects, TB patients had higher frequencies ofESAT-6-induced CD8+ lymphoblasts (p<0.001), higher proportions of ESAT-6-induced IFN-γ+TNF-α+ CD4+ Tlymphocytes (p<0.05), and lower proportions of HBHA-induced IFN-γ+TNF-α+IL-2+ (p<0.05) CD4+ T lymphocytes.Conclusions: These data provide new biomarkers to discriminate active TB from LTBI, and more interestingly,help to identify LTBI subjects with increased likelihood to develop TB disease.

Preliminary results on clinical and immunological effects of thymopentin in AIDS

SCOPUS: ar.j