Autoimmunity in 2013

Autoimmunity in 2016

The number of peer-reviewed articles published during the 2016 solar year and retrieved using the "autoimmunity" key word remained stable while gaining a minimal edge among the immunology articles. Nonetheless, the quality of the publications has been rising significantly and, importantly, acquisitions have become available through scientific journals dedicated to immunology or autoimmunity. Major discoveries have been made in the fields of systemic lupus erythematosus, rheumatoid arthritis, autoimmunity of the central nervous system, vasculitis, and seronegative spondyloarthrithritides. Selected examples include the role of IL17-related genes and long noncoding RNAs in systemic lupus erythematosus or the effects of anti-pentraxin 3 (PTX3) in the treatment of this paradigmatic autoimmune condition. In the case of rheumatoid arthritis, there have been reports of the role of induced regulatory T cells (iTregs) or fibrocytes and T cell interactions with exciting implications. The large number of studies dealing with neuroimmunology pointed to Th17 cells, CD56(bright) NK cells, and low-level TLR2 ligands as involved in multiple sclerosis, along with a high salt intake or the micriobiome-derived Lipid 654. Lastly, we focused on the rare vasculitides to which numerous studies were devoted and suggested that unsuspected cell populations, including monocytes, mucosal-associated invariant T cells, and innate lymphoid cells, may be crucial to ANCA-associated manifestations. This brief and arbitrary discussion of the findings published in 2016 is representative of a promising background for developments that will enormously impact the work of laboratory scientists and physicians at an exponential rate.

Autoimmunity in 2014

Our PubMed search for peer-reviewed articles published in the 2014 solar year retrieved a significantly higher number of hits compared to 2013 with a net 28 % increase. Importantly, full articles related to autoimmunity constitute approximately 5 % of immunology articles. We confirm that our understanding of autoimmunity is becoming a translational paradigm with pathogenetic elements rapidly followed by new treatment options. Furthermore, numerous clinical and pathogenetic elements and features are shared among autoimmune diseases, and this is well illustrated in the recent literature. More specifically, the past year witnessed critical revisions of our understanding and management of antiphospholipid syndrome with new exciting data on the pathogenicity of the serum anti-beta2 glycoprotein autoantibody, a better understanding of the current and new treatments for rheumatoid arthritis, and new position papers on important clinical questions such as vaccinations in patients with autoimmune disease, comorbidities, or new classification criteria. Furthermore, data confirming the important connections between innate immunity and autoimmunity via toll-like receptors or the critical role of T regulatory cells in tolerance breakdown and autoimmunity perpetuation were also reported. Lastly, genetic and epigenetic data were provided to confirm that the mosaic of autoimmunity warrants a susceptible individual background which may be geographically determined and contribute to the geoepidemiology of diseases. The 2014 literature in the autoimmunity world should be cumulatively regarded as part of an annus mirabilis in which, on a different level, the 2014 Annual Meeting of the American College of Rheumatology in Boston was attended by over 16,000 participants with over selected 3000 abstracts.

T-helper 17 cell polarization in pulmonary arterial hypertension

BACKGROUND

Inflammation may contribute to the pathobiology of pulmonary arterial hypertension (PAH). Deciphering the PAH fingerprint on the inflammation orchestrated by dendritic cells (DCs) and T cells, key driver and effector cells, respectively, of the immune system, may allow the identification of immunopathologic approaches to PAH management.

METHODS

Using flow cytometry, we performed immunophenotyping of monocyte-derived DCs (MoDCs) and circulating lymphocytes from patients with idiopathic PAH and control subjects. With the same technique, we performed cytokine profiling of both populations following stimulation, coculture, or both. We tested the immunomodulatory effects of a glucocorticoid (dexamethasone [Dex]) on this immunophenotype and cytokine profile. Using an epigenetic approach, we confirmed the immune polarization in blood DNA of patients with PAH.

RESULTS

The profile of membrane costimulatory molecules of PAH MoDCs was similar to that of control subjects. However, PAH MoDCs retained higher levels of the T-cell activating molecules CD86 and CD40 after Dex pretreatment than did control MoDCs. This was associated with an increased expression of IL-12p40 and a reduced migration toward chemokine (C-C motif) ligand 21. Moreover, both with and without Dex, PAH MoDCs induced a higher activation and proliferation of CD4+ T cells, associated with a reduced expression of IL-4 (T helper 2 response) and a higher expression of IL-17 (T helper 17 response). Purified PAH CD4+ T cells expressed a higher level of IL-17 after activation than did those of control subjects. Lastly, there was significant hypomethylation of the IL-17 promoter in the PAH blood DNA as compared with the control blood.

CONCLUSIONS

We have highlighted T helper 17 cell immune polarization in patients with PAH, as has been previously demonstrated in other chronic inflammatory and autoimmune conditions.