Rapid diagnosis of active Mycobacterium tuberculosis (Mtb) infection remains a clinical and laboratory challenge. We have analyzed the cytokine profile (interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α) and interleukin-2 (IL-2)) of Mtb-specific T cells by polychromatic flow cytometry. We studied Mtb-specific CD4+ T cell responses in subjects with latent Mtb infection and active tuberculosis disease. The results showed substantial increase in the proportion of single-positive TNF-α Mtb-specific CD4+ T cells in subjects with active disease, and this parameter was the strongest predictor of diagnosis of active disease versus latent infection. We validated the use of this parameter in a cohort of 101 subjects with tuberculosis diagnosis unknown to the investigator. The sensitivity and specificity of the flow cytometry-based assay were 67% and 92%, respectively, the positive predictive value was 80% and the negative predictive value was 92.4%. Therefore, the proportion of single-positive TNF-α Mtb-specific CD4+ T cells is a new tool for the rapid diagnosis of active tuberculosis disease.

We studied CD8 T cell responses against HIV-1, cytomegalovirus, Epstein-Barr virus, and influenza in 128 subjects and demonstrate that polyfunctional CD8 T cell responses, also including IL-2 production and Ag-specific proliferation, are predominantly driven by virus epitopes restricted by HLA-B alleles. Interestingly, these protective CD8 T cells are equipped with low-avidity T cell receptors (TCRs) for the cognate virus epitope. Conversely, HLA-Arestricted epitopes are mostly associated with ''only effector'' IFN-␥-secreting, with cytotoxicity, and with the lack of IL-2 production and Ag-specific proliferation. These CD8 T cells are equipped with high-avidity TCR and express higher levels of the T cell exhaustion marker PD-1. Thus, the functional profile of the CD8 T cell response is strongly influenced by the extent to which there is stimulation of polyfunctional (predominantly restricted by HLA-B) versus only effector (restricted by HLA-A) T cell responses. These results provide the rationale for the observed protective role of HLA-B in HIV-1-infection and new insights into the relationship between TCR avidity, PD-1 expression, and the functional profile of CD8 T cells.

BackgroundIn 2012, a European initiative called Single Hub and Access point for pediatric Rheumatology in Europe (SHARE) was launched to optimise and disseminate diagnostic and management regimens in Europe for children and young adults with rheumatic diseases. Juvenile dermatomyositis (JDM) is a rare disease within the group of paediatric rheumatic diseases (PRDs) and can lead to significant morbidity. Evidence-based guidelines are sparse and management is mostly based on physicians' experience. Consequently, treatment regimens differ throughout Europe.ObjectivesTo provide recommendations for diagnosis and treatment of JDM.MethodsRecommendations were developed by an evidence-informed consensus process using the European League Against Rheumatism standard operating procedures. A committee was constituted, consisting of 19 experienced paediatric rheumatologists and 2 experts in paediatric exercise physiology and physical therapy, mainly from Europe. Recommendations derived from a validated systematic literature review were evaluated by an online survey and subsequently discussed at two consensus meetings using nominal group technique. Recommendations were accepted if >80% agreement was reached.ResultsIn total, 7 overarching principles, 33 recommendations on diagnosis and 19 recommendations on therapy were accepted with >80% agreement among experts. Topics covered include assessment of skin, muscle and major organ involvement and suggested treatment pathways.ConclusionsThe SHARE initiative aims to identify best practices for treatment of patients suffering from PRD. Within this remit, recommendations for the diagnosis and treatment of JDM have been formulated by an evidence-informed consensus process to produce a standard of care for patients with JDM throughout Europe.