Disease-association of different killer cell immunoglobulin-like receptors (KIR) and HLA-C gene combinations in reactive arthritis

Drivers of Inflammation in Psoriatic Arthritis: the Old and the New

PURPOSE OF REVIEW

The recognition that IL-17 is produced by many lymphoid-like cells other than CD4+ T helper (Th17) cells raises the potential for new pathogenic pathways in IBD/psoriasis/SpA. We review recent knowledge concerning the role of unconventional and conventional lymphocytes expressing IL-17 in human PsA and axSpA.

RECENT FINDINGS

Innate-like lymphoid cells, namely gamma delta (γδ) T-cells, invariant natural killer T (iNKT) cells and mucosal-associated invariant T (MAIT) cells, together with innate lymphoid cells (ILCs) are found at sites of disease in PsA/SpA. These cells are often skewed to Type-17 profiles and may significantly contribute to IL-17 production. Non-IL-23 dependent IL-17 production pathways, utilising cytokines such as IL-7 and IL-9, also characterise these cells. Both conventional CD4 and CD8 lymphocytes show pathogenic phenotypes at sites of disease. A variety of innate-like lymphoid cells and conventional lymphocytes contribute towards IL-17-mediated pathology in PsA/SpA. The responses of these cells to non-conventional immune and non-immune stimuli may explain characteristic clinical features of these diseases and potential therapeutic mechanisms of therapies such as Jak inhibitors.

The Genetics of Spondyloarthritis

The term spondyloarthritis (SpA) encompasses a group of chronic inflammatory diseases with common features in terms of clinical presentation and genetic predisposition. SpA is characterized by inflammation of the spine and peripheral joints, and is also be associated with extra-articular inflammatory manifestations such as psoriasis, uveitis, or inflammatory bowel disease (IBD). The etiology of SpA is not completely understood, but it is known to have a strong genetic component dominated by the human leukocyte antigen (HLA)-B27. In the last few years, our understanding of genetic susceptibility to SpA, particularly ankylosing spondylitis (AS), has greatly improved thanks to the findings derived from powered genome-wide association studies (GWAS) based on single nucleotide polymorphism (SNP) arrays. These studies have identified many candidate genes, therefore providing new potential directions in the exploration of disease mechanisms, especially with regard to the key role of the immune system in the pathogenesis of SpA. SpA is a complex disease where genetic variability, environmental factors, and random events interact to trigger pathological pathways. The aim of this review is to summarize current findings on the genetics of SpA, some of which might help to study new treatment approaches.

Association of Killer Cell Immunoglobulin-like Receptor and Human Leukocyte antigen-C Genotype with HLA-B27 Associated Acute Anterior Uveitis and Idiopathic Acute Anterior Uveitis in a Chinese Han Population

Purpose whether killer cell immunoglobulin-like receptors (KIRs) and human leukocyte antigens C (HLA-C) are associated with HLA-B27 associated acute anterior uveitis (B27AAU) and idiopathic AAU (IAAU) remains unclear.Methods PCR with sequence-specific primers was used to analyze KIR genes and HLA-C alleles in a Chinese Han population of 196AAU patients and 210 control subjects.Results The higher frequencies of HLA-C2 and KIR2DL1/HLA-C2 (p = .009 and p = .044, respectively) and the lower frequencies of HLA-C1C1 and HLA-C1 (p = .034 and p = .009, respectively) were observed in B27AAU than control group. The higher frequencies of KIR2DL2 and KIR2DL2/HLA-C1 (p = .009 and p = .044, respectively) and the lower frequencies of KIR2DL3 and KIR2DL3/HLA-C1 (p = .000 and p = .001, respectively) were observed in IAAU than control group.Conclusions HLA-C2 and KIR2DL1/HLA-C2, KIR2DL2, and KIR2DL2/HLA-C1 might be susceptible for B27AAU and IAAU, respectively. HLA-C1C1 and HLA-C1, KIR2DL3 and KIR2DL3/HLA-C1 might protect from B27AAU and IAAU, respectively.

European Patent in Immunoncology: From Immunological Principles of Implantation to Cancer Treatment

The granted European patent EP 2 561 890 describes a procedure for an immunological treatment of cancer. It is based on the principles of the HLA-supported communication of implantation and pregnancy. These principles ensure that the embryo is not rejected by the mother. In pregnancy, the placenta, more specifically the trophoblast, creates an “interface” between the embryo/fetus and the maternal immune system. Trophoblasts do not express the “original” HLA identification of the embryo/fetus (HLA-A to -DQ), but instead show the non-classical HLA groups E, F, and G. During interaction with specific receptors of NK cells (e.g., killer-immunoglobulin-like receptors (KIR)) and lymphocytes (lymphocyte-immunoglobulin-like receptors (LIL-R)), the non-classical HLA groups inhibit these immunocompetent cells outside pregnancy. However, tumors are known to be able to express these non-classical HLA groups and thus make use of an immuno-communication as in pregnancies. If this occurs, the prognosis usually worsens. This patent describes, in a first step, the profiling of the non-classical HLA groups in primary tumor tissue as well as metastases and recurrent tumors. The second step comprises tailored antibody therapies, which is the subject of this patent. In this review, we analyze the underlying mechanisms and describe the currently known differences between HLA-supported communication of implantation and that of tumors.