The Status of Human Rights Protection in Europe: It’s complicated

The UK has voted to leave the European Union and Prime Minister Theresa May has expressed her aversion to the European Convention on Human Rights, but confusion abounds as to what the current architecture of Europe is, let alone what it might look like in the future. This article seeks to provide a comprehensive overview of the development of supranational human rights protections in Europe and the status of the current quest for greater integration. In particular, the stalled movement towards the accession of the EU to the ECHR is examined and likened to a riddle: to avoid subjecting Member States to conflicting obligations, the ECHR must be granted ultimate authority in the field of human rights, but without compromising the autonomy of EU law. The article concludes with a conversation with Dr Sonia Morano-Foadi, whose extensive research into the European human rights institutions enables her to shed some light on the likelihood of the accession riddle ever being solved and to provide a prognosis for European rights protections in the future

T cell epitope clustering in the highly immunogenic BZLF1 antigen of Epstein-Barr virus

Polymorphism in the human leukocyte antigen (HLA) loci ensures that the CD8 T cell response to viruses is directed against a diverse range of antigenic epitopes, thereby minimizing the impact of virus escape mutation across the population. The BZLF1 antigen of Epstein-Barr virus is an immunodominant target for CD8 T cells, but the response has been characterized only in the context of a limited number of HLA molecules due to incomplete epitope mapping. We have now greatly expanded the number of defined CD8 T cell epitopes from BZLF1, allowing the response to be evaluated in a much larger proportion of the population. Some regions of the antigen fail to be recognized by CD8 T cells, while others include clusters of overlapping epitopes presented by different HLA molecules. These highly immunogenic regions of BZLF1 include polymorphic sequences, such that up to four overlapping epitopes are impacted by a single amino acid variation common in different regions of the world. This focusing of the immune response to limited regions of the viral protein could be due to sequence similarity to human proteins creating "immune blind spots" through self-tolerance. This study significantly enhances the understanding of the immune response to BZLF1, and the precisely mapped T cell epitopes may be directly exploited in vaccine development and adoptive immunotherapy

Multivariate analysis using high definition flow cytometry reveals distinct T cell repertoires between the fetal–maternal interface and the peripheral blood

The human T cell compartment is a complex system and while some information is known on repertoire composition and dynamics in the peripheral blood, little is known about repertoire composition at different anatomical sites. Here, we determine the T cell receptor beta variable (TRBV) repertoire at the decidua and compare it with the peripheral blood during normal pregnancy and pre-eclampsia. We found total T cell subset disparity of up to 58% between sites, including large signature TRBV expansions unique to the fetal–maternal interface. Defining the functional nature and specificity of compartment-specific T cells will be necessary if we are to understand localized immunity, tolerance, and pathogenesis

Pre-emptive and therapeutic adoptive immunotherapy for nasopharyngeal carcinoma: Phenotype and effector function of T cells impact on clinical response

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Day-4 Myeloid Dendritic Cells Pulsed with Whole Tumor Lysate Are Highly Immunogenic and Elicit Potent Anti-Tumor Responses

“Day-7” myeloid DCs are commonly used in the clinic. However, there is a strong need to develop DCs faster that have the same potent immunostimulatory capacity as “Day-7” myeloid DCs and at the same time minimizing time, labor and cost of DC preparations. Although “2 days” DCs can elicit peptide-specific responses, they have not been demonstrated to engulf, process and present complex whole tumor lysates, which could be more convenient and personalized source of tumor antigens than defined peptides. In this preclinical study, we evaluated the T-cell stimulatory capacity of Day-2, Day-4, and Day-7 cultured monocyte-derived DCs loaded with SKOV3 cell whole lysate prepared by freeze-thaw or by UVB-irradiation followed by freeze-thaw, and matured with lipopolysaccharide (LPS) and interferon (IFN)-gamma. DCs were evaluated for antigen uptake, and following maturation with LPS and IFN-gamma, DCs were assessed for expression of CD80, CD40, CD86, ICAM-1 and CCR7, production of IL-12p70 and IP-10, and induction of tumor-specific T-cell responses. Day-4 and Day-7 DCs exhibited similar phagocytic abilities, which were superior to Day-2 DCs. Mature Day-7 DCs expressed the highest CD40 and ICAM-1, but mature Day-4 DCs produced the most IL-12p70 and IP-10. Importantly, Day-4 and Day-7 DCs derived from ovarian cancer patients stimulated equally strongly tumor-specific T-cell responses. This is the first study demonstrating the highly immunogenic and strong T-cell stimulatory properties of Day-4 myeloid DCs, and provided important preclinical data for rapid development of potent whole tumor lysate-loaded DC vaccines that are applicable to many tumor types

Allelic polymorphism in the T cell receptor and its impact on immune responses

In comparison to human leukocyte antigen (HLA) polymorphism, the impact of allelic sequence variation within T cell receptor (TCR) loci is much less understood. Particular TCR loci have been associated with autoimmunity, but the molecular basis for this phenomenon is undefined. We examined the T cell response to an HLA-B*3501-restricted epitope (HPVGEADYFEY) from Epstein-Barr virus (EBV), which is frequently dominated by a TRBV9*01 public TCR (TK3). However, the common allelic variant TRBV9*02, which differs by a single amino acid near the CDR2β loop (Gln55→His55), was never used in this response. The structure of the TK3 TCR, its allelic variant, and a nonnaturally occurring mutant (Gln55→Ala55) in complex with HLA-B*3501 revealed that the Gln55→His55 polymorphism affected the charge complementarity at the TCR-peptide-MHC interface, resulting in reduced functional recognition of the cognate and naturally occurring variants of this EBV peptide. Thus, polymorphism in the TCR loci may contribute toward variability in immune responses and the outcome of infection

Comparison of peptide-major histocompatibility complex tetramers and dextramers for the identification of antigen-specific T cells

Fluorochrome-conjugated peptide–major histocompatibility complex (pMHC) multimers are widely used for flow cytometric visualization of antigen-specific T cells. The most common multimers, streptavidin–biotin-based ‘tetramers’, can be manufactured readily in the laboratory. Unfortunately, there are large differences between the threshold of T cell receptor (TCR) affinity required to capture pMHC tetramers from solution and that which is required for T cell activation. This disparity means that tetramers sometimes fail to stain antigen-specific T cells within a sample, an issue that is particularly problematic when staining tumour-specific, autoimmune or MHC class II-restricted T cells, which often display TCRs of low affinity for pMHC. Here, we compared optimized staining with tetramers and dextramers (dextran-based multimers), with the latter carrying greater numbers of both pMHC and fluorochrome per molecule. Most notably, we find that: (i) dextramers stain more brightly than tetramers; (ii) dextramers outperform tetramers when TCR–pMHC affinity is low; (iii) dextramers outperform tetramers with pMHC class II reagents where there is an absence of co-receptor stabilization; and (iv) dextramer sensitivity is enhanced further by specific protein kinase inhibition. Dextramers are compatible with current state-of-the-art flow cytometry platforms and will probably find particular utility in the fields of autoimmunity and cancer immunology

CD8+ T cells from a novel T cell receptor transgenic mouse induce liver-stage immunity that can be boosted by blood-stage infection in rodent malaria

To follow the fate of CD8+ T cells responsive to Plasmodium berghei ANKA (PbA) infection, we generated an MHC I-restricted TCR transgenic mouse line against this pathogen. T cells from this line, termed PbT-I T cells, were able to respond to blood-stage infection by PbA and two other rodent malaria species, P. yoelii XNL and P. chabaudi AS. These PbT-I T cells were also able to respond to sporozoites and to protect mice from liver-stage infection. Examination of the requirements for priming after intravenous administration of irradiated sporozoites, an effective vaccination approach, showed that the spleen rather than the liver was the main site of priming and that responses depended on CD8α+ dendritic cells. Importantly, sequential exposure to irradiated sporozoites followed two days later by blood-stage infection led to augmented PbT-I T cell expansion. These findings indicate that PbT-I T cells are a highly versatile tool for studying multiple stages and species of rodent malaria and suggest that cross-stage reactive CD8+ T cells may be utilized in liver-stage vaccine design to enable boosting by blood-stage infections