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Evidence of autoimmune disease associated with hepatitis C virus (HCV)-infection has important clinical implications. A systematic profile of these autoantibodies in relevant clinical cohorts relative to healthy controls is needed to better inform current standard of care for chronic hepatitis C. Samples from an Australian cohort of chronic HCV-infected subjects (n=127) were tested for the presence of 19 diagnostic autoantibodies and compared with data available from a control cohort representing a general Caucasian population (n=198). Chronic HCV-infected individuals had a greater number of autoantibodies than controls (p

Abacavir hypersensitivity syndrome (ABC HSS) is strongly associated with carriage of human leukocyte antigen (HLA)-B*57:01, which has a 100% negative predictive value for the development of ABC HSS. However, 45% of individuals who carry HLA-B*57:01 can tolerate ABC. We investigated immune and non-immune related genes in ABC HSS (n = 95) and ABC tolerant (n = 43) HLA-B*57:01 + patients to determine other factors required for the development of ABC HSS. Assignment of phenotype showed that ABC HSS subjects were significantly less likely than tolerants to carry only ERAP1 hypoactive trimming allotypes (p = 0.02). An altered self-peptide repertoire model by which abacavir activates T cells is in keeping with observation that endoplasmic reticulum aminopeptidase 1 (ERAP1) allotypes that favour efficient peptide trimming are more common in ABC HSS patients compared to patients who tolerate ABC. Independently, non-specific immune activation via soluble cluster of differentiation antigen 14 (sCD14) may also influence susceptibility to ABC HSS.

Tissue integrity and repair is assisted by tissue-resident leukocytes, which also provide immediate responses to infection. It is unclear to what extent tissue-resident cells are perturbed following solid organ transplantation. For the first time, we report on the varied fates of 13 subsets of B, T and ILC lymphocytes after murine liver and heart transplantation in the absence of tissue mismatch and immunosuppression . Strikingly, donor-derived unconventional lymphocytes are predominantly maintained in livers, but not hearts, as long-term tissue-resident and self-renewing populations. In contrast, donor conventional lymphocytes are rapidly displaced by recipient populations, but this does not occur in the absence of recipient T and B cells. Overall, infiltrating recipient cells fail to recreate the native organ’s phenotypically diverse tissue-resident lymphocyte composition. These changes in post-transplant immunity are likely to leave the graft vulnerable to infection and impair long-term graft function.

HLA-B*27 is associated with spontaneous HCV genotype 1 clearance. HLA-B*27-restricted CD8+ T cells target three NS5B epitopes. Two of these epitopes are dominantly targeted in the majority of HLA-B*27+ patients. In chronic infection, viral escape occurs consistently in these two epitopes. The third epitope (NS5B2820) was dominantly targeted in an acutely infected patient. This was in contrast, however, to the lack of recognition and viral escape in the large majority of HLA-B*27+ patients. Here, we set out to determine the host factors contributing to selective targeting of this epitope. Four-digit HLA class I typing and viral sequence analyses were performed in 78 HLA-B*27+ patients with chronic HCV genotype 1 infection. CD8+ T cell analyses were performed in a subset of patients. In addition, HLA/peptide affinity was compared for HLA-B*27:02 and 05. The NS5B2820 epitope is only restricted by the HLA-B*27 subtype HLA-B*27:02 (that is frequent in Mediterranean populations), but not by the prototype HLA-B*27 subtype B*27:05. Indeed, the epitope is very dominant in HLA-B*27:02+ patients and is associated with viral escape mutations at the anchor position for HLA-binding in 12 out of 13 HLA-B*27:02+ chronically infected patients. The NS5B2820 epitope is immunodominant in the context of HLA-B*27:02, but is not restricted by other HLA-B*27 subtypes. This finding suggests an important role of HLA subtypes in the restriction of HCV-specific CD8+ responses. With minor HLA subtypes covering up to 39% of specific populations, these findings may have important implications for the selection of epitopes for global vaccines. Financial support: CNH was supported by the Deutsche Forschungsgemeinschaft (DFG; Emmy Noether Program, NE 1567/1-1). CNH and RT were supported by the European Union (EFRE Interreg IV Oberrhein, project A30). SV was supported by the German Ministry of Education and Research (BMBF, grant no. 01 KI 1008E). DL was supported by the Ministerio de Ciencia e Innovación, Spain. This project was funded, in part, by Federal funds from the National Institute of Allergy and Infectious Diseases (NIAID), grants R01-AI067926 (TMA) and U19 AI082630 (TMA and GML), and the Swiss HIV Cohort Study, supported by the Swiss National Science Foundation (grant #33CS30_134277). Sí

The Killer Ig-like receptors (KIRs) on NK cells regulate NK activity via the recognition of specific HLA class I products on the surface of target cells. To investigate the level at which these genetically polymorphic receptors and ligands influence HIV-1 disease progression, we examined the effect of KIR and HLA genotype on HIV outcome. We observed a significant association between particular combinations of KIR epitopes expressed by HLA-B/-C haplotypes and propose that the repertoire of KIR epitopes expressed by HLA-B and HLA-C alleles within the context of particular haplotypes may be an important component of the NK mediated immune response to HIV and/or other infectious pathogens.

Members of the killer immunoglobulin (Ig)-like receptor (KIR) gene family are tightly clustered on human chromosome 19q13.4. Despite considerable variation in KIR gene content and allelic polymorphism, most KIR haplotypes belong to one of two broad groups termed A and B. The availability of contiguous genomic sequences for these haplotypes has allowed us to compare their genomic organization, nucleotide (nt) diversity and reconstruct their evolutionary history. The haplotypes have a framework of three conserved blocks containing (i) KIR3DL3, (ii) KIR3DP1, 2DL4, and (iii) KIR3DL2 that are interrupted by two variable segments that differ in the number and type of KIR genes. Low (0.05%) nucleotide diversity was detected across the centromeric and telomeric boundaries of the KIR gene cluster while higher SNP density (0.2%) occurred within the central region containing the KIR2DL4 gene. Phylogenetic and genomic analyses have permitted the reconstruction of a hypothetical ancestral haplotype that has revealed common groupings and differences between the KIR genes of the two haplotypes. The present phylogenetic and genomic comparison of the two sequenced KIR haplotypes provides a framework for a more thorough examination of KIR haplotype variations, diversity and evolution in human populations and between humans and non-human primates.

The genomic matching technique (GMT) improves survival following bone marrow transplantation (BMT) between unrelated donor and recipient pairs correlating with a decrease in incidence and severity of graft-versus-host disease (GvHD). The principles of this technique are based on the duplication and polymorphic characteristics of the major histocompatibility complex (MHC). Specifically, the beta block GMT matches for a 300 kb region that contains the human leukocyte antigen (HLA-B and -C) genes as well as other non-HLA genes such as the natural killer cell receptor ligand PERB11 (MIC). The block contains two large segmental duplications. One results in two PERB11 genes (11.1 and 11.2), the other in two class I genes (HLA-B and -C). With the complete sequencing of the class I region of the MHC in different haplotypes, we can now show that the beta block GMT profiles reflect amplification of the duplicated PERB11 segments and not the duplicated segments containing HLA-B and -C, and yet provide a signature that characterizes the entire block rather than individual loci.

The genomic matching technique (GMT) was developed to characterize polymorphic sequences within the human major histocompatibility complex (MHC), known as polymorphic frozen blocks (PFBs). PFBs are 200–300 kb sequences containing duplications, indels and SNPs. The power of the GMT to differentiate between individuals at the DNA level means that it can be applied as an exclusion tool in forensic science. Here, the GMT is applied to the alpha block in the MHC.

Chimpanzees (Pan Troglodytes) and humans are closely related and belong to the same subfamily, Homininae. The approximately 1.8% genetic difference that exists between humans and the chimpanzees must be responsible for observed differences between these two species. It has been shown that chimpanzees can be infected with HIV, but AIDS has not been reported. Furthermore, the prevalence of autoimmune diseases may be low in this species. For instance, type II diabetes occurs, but type I (autoimmune) diabetes (IDDM), to our knowledge, has not been reported. In humans, susceptibility genes for MG and IDDM have been localized to the region between TNF and HLA-B. This region may also influence the rate of progression to death after HIV infection. We have identified differences in this region between humans and the chimpanzees. As shown by PFGE, the TNF to Patr-B region in the chimpanzees is approximately 130-160 kb shorter than the equivalent in humans. Southern and sequence analyses indicate that the deletions in chimpanzees (insertions in humans) include one copy of CL (approximately 10 kb) and the X sequences (30 kb). Obviously, other deletions/insertions (approximately 120 kb) need to be identified. Since CL has been shown to be transcribed, the results imply the lack of the gene or, at least, a different gene copy number in the chimpanzees, and we propose that such differences may be relevant to the observed functional differences. We demonstrate here a strategy to identify critical genes responsible for disease development.

vectors have generated great scientific interest in recent years and appear to be superior viral vectors with great potential in vaccine regimes. Their potential use in humans, however, is limited by natural anti-vector immunity to human adenoviruses, but this problem could be largely circumvented by the use of simian adenoviral vaccine vectors. Recent clinical trials have suggested that the simian adenoviral vector AdCh63 is a promising clinical candidate. We have developed vectors (of human and simian origin) and MVA encoding a novel construct based on P. falciparum MSP-1 and have undertaken comparative immunogenicity studies in mice. The antigen, termed ‘PfM128, is based on the five highly conserved blocks from P. falciparum MSP-1, plus both dimorphic alleles of the 42 kDa region. We have used these vectors to map novel murine Tcell epitopes within PfMSP-1. We compare antibody titres and polyfunctional T cell responses when simian adenoviral vector AdCh63 is used to replace AdHu5 in a heterologous prime-boost regime. These data suggest that simian adenoviral vectors have great potential for use in future blood-stage malaria vaccination regimes in humans.

Background Environmental changes influencing the interaction between the maturing immune system and pathogen exposure are implicated in the rising rates of allergic disease. There is emerging evidence that differences in innate immune function contribute to the development of allergy. Consequently, associated genetic factors may be critical for the difference in immune ontogeny, seen in allergic children. Aims We examined if genetic variation associated with the IL28B gene, encoding for the potent immune modulator IFN lambda 3, contributes to the divergent immune response in selected children who were followed from birth to 5 years of age (35 allergic and 35 non-allergic children). Results We found that carriage of the T allele of the SNP rs12979860, tagging the IL28B gene, is significantly associated with allergy ( p = 0.004; OR 4.56). This association increases with age and is particularly evident in girls (OR 16). In addition, variation at rs12979860 correlates with differences in the pro-inflammatory profile (IL1B production) at birth after TLR stimulation of cord blood cells. Conclusion In the context of rising rates of disease, the genetic variation described may contribute to key differences in innate immune development of allergic children and points towards a role of IFN lambda III in allergic disease pathogenesis.

Methods: HBV-specific T cells were expanded in a 2-dimensional combinatorial expansion assay (67 different conditions from 11 factors) and the frequency of HBV-specific T cells was quantified by intra-cellular cytokine staining. Due to the exponentially increasing technical difficulties associated with analyzing multiple factors of T cell dysfunction, we coupled the expansion assay together with fluorescent cell barcoding to achieve a high throughput flow cytometric analysis. Results: By varying the concentration of an amine reactive dye, we were able to obtain 5 distinct fluorescent barcodes which were used to label different samples. This allows us to pool 5 samples into a single tube, reducing staining antibody consumption and the number of flow cytometer acquisitions to an operationally manageable quantity (from 70 to 14 tubes). The flow cytometric data of each tube was then deconvoluted into the individual samples based on the fluorescent barcodes and analyzed. Interestingly, preliminary results from 4 chronic HBV patients and 4 healthy subjects show that combinations which blocks apoptosis through the action of a pan-caspase inhibitor was able to preferentially enhance the in vitro expansion of exhausted HBV-specific T cells and not functional T cells specific for other viruses (CMV or FLU). Conclusion: The development of this assay makes it possible to simultaneously analyze combinations of multiple strategies to rescue exhausted HBV-specific T cells. Further in-depth analysis is ongoing to determine the ideal combinations to rescue exhausted HBV-specific T cells.

NK cell receptors and HLA molecules are intimately involved in the immune response against viral infections. The killer immunoglobulin-like receptors (KIRs) on NK cells regulate NK cell responses via the recognition of their particular HLA class I ligands. At the genomic level, both genetic systems are polymorphic and have recognised haplotypes, which adds complexity to their interaction. Previously, we and others have shown the association of HLA class I with HIV progression. Recently, the Carrington group observed a synergistic effect involving the activating KIR3DS1 gene and HLA-B Bw4–80Ile on the rate of depletion of CD4+ T cells. To further investigate the relationship between the two genetic systems, we examined changes in viral load in 249 pre-treatment patients from the Western Australia HIV cohort. Genetic variants known to affect HIV progression including HLA-Bw4–80Ile but not KIR3DS1 were associated with differences in HIV-1 viral load set point. When we examined only those patients with known seroconversion dates, we found that the presence of the KIR3DS1 gene was associated with more rapid decline in the proportion of CD4+ T cells (p=0.01) but were unable to show a KIR3DS1 and Bw4–80Ile interaction. The presence of other KIR genes (viz KIR2DS2, KIR2DL2 and KIR2DS1), all found on KIR B group haplotypes, were also associated with a more rapid progression, whilst some KIR genes found the A haplotype with delayed progression We suggest that multiple KIR genes influence outcome in HIV infection. Further analyses of KIR haplotypes is needed to understand the complex interactions between KIR genes and their ligands in driving NK cell responses to HIV.