Human CD8 tumor-infiltrating lymphocytes (TILs) with impaired effector functions and PD-1 expression are categorized as exhausted. However, the exhaustion-like features reported in TILs might stem ...from their activation rather than the consequence of T cell exhaustion itself. Using CRISPR-Cas9 and lentiviral overexpression in CD8 T cells from non-cancerous donors, we show that the T cell receptor (TCR)-induced transcription factor interferon regulatory factor 4 (IRF4) promotes cell proliferation and PD-1 expression and hampers effector functions and expression of nuclear factor κB (NF-κB)-regulated genes. While CD8 TILs with impaired interferon γ (IFNγ) production exhibit activation markers IRF4 and CD137 and exhaustion markers thymocyte selection associated high mobility group box (TOX) and PD-1, activated T cells in patients with COVID-19 do not demonstrate elevated levels of TOX and PD-1. These results confirm that IRF4+ TILs are exhausted rather than solely activated. Our study indicates, however, that PD-1 expression, low IFNγ production, and active cycling in TILs are all influenced by IRF4 upregulation after T cell activation.
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•IRF4 impairs cytokine production in human CD8 T cells•IRF4 promotes PD-1 expression and T cell proliferation•IRF4 regulates cell cycle genes and impairs NF-κB-regulated gene expression•Exhaustion features in TILs are correlated to their activation and IRF4 expression
Hirsch et al. subjected primary human CD8 T cells to IRF4 overexpression or knockout and assessed T cell functions and the transcriptome. The TCR-induced transcription factor IRF4 promotes proliferation and PD-1 expression but hampers effector functions and expression of NF-κB-regulated genes. They also compared CD8 tumor-infiltrating lymphocytes to activated T cells in patients with COVID-19.
The transcription factor HELIOS is primarily known for its expression in CD4 regulatory T cells, both in humans and mice. In mice, HELIOS is found in exhausted CD8 T cells. However, information on ...human HELIOS
CD8 T cells is limited and conflicting.
In this study, we characterized by flow cytometry and transcriptomic analyses human HELIOS
CD8 T cells.
These T cells primarily consist of memory cells and constitute approximately 21% of blood CD8 T cells. In comparison with memory HELIOS
T-BET
CD8 T cells that displayed robust effector functions, the memory HELIOS
T-BET
CD8 T cells produce lower amounts of IFN-γ and TNF-α and have a lower cytotoxic potential. We wondered if these cells participate in the immune response against viral antigens, but did not find HELIOS
cells among CD8 T cells recognizing CMV peptides presented by HLA-A2 and HLA-B7. However, we found HELIOS
CD8 T cells that recognize a CMV peptide presented by MHC class Ib molecule HLA-E. Additionally, a portion of HELIOS
CD8 T cells is characterized by the expression of CD161, often used as a surface marker for identifying T
cells. These CD8 T cells express T
/T
-related genes encoding RORgt, RORa, PLZF, and CCL20.
Our findings emphasize that HELIOS is expressed across various CD8 T cell populations, highlighting its significance beyond its role as a transcription factor for Treg or exhausted murine CD8 T cells. The significance of the connection between HELIOS and HLA-E restriction is yet to be understood.
PITX1 is a homeobox transcription factor essential for hindlimb morphogenesis. Two PITX1‐related human disorders have been reported to date: PITX1 ectopic expression causes Liebenberg syndrome, ...characterized by malformation of upper limbs showing a “lower limb” appearance; PITX1 deletions or missense variation cause a syndromic picture including clubfoot, tibial hemimelia, and preaxial polydactyly. We report two novel PITX1 missense variants, altering PITX1 transactivation ability, in three individuals from two unrelated families showing a distinct recognizable autosomal dominant syndrome, including first branchial arch, pelvic, patellar, and male genital abnormalities. This syndrome shows striking similarities with the Pitx1−/− mouse model. A partial phenotypic overlap is also observed with Ischiocoxopodopatellar syndrome caused by TBX4 haploinsufficiency, and with the phenotypic spectrum caused by SOX9 anomalies, both genes being PITX1 downstream targets. Our study findings expand the spectrum of PITX1‐related disorders and suggest a common pattern of developmental abnormalities in disorders of the PITX1–TBX4–SOX9 signaling pathway.
Thrombocytopenia‐absent radius (TAR) syndrome is characterized by radial defect and neonatal thrombocytopenia. It is caused by biallelic variants of RBM8A gene (1q21.1) with the association of a null ...allele and a hypomorphic noncoding variant. RBM8A encodes Y14, a core protein of the exon junction complex involved in messenger RNA maturation. To date, only two hypomorphic variants have been identified. We report on a cohort of 26 patients affected with TAR syndrome and carrying biallelic variants in RBM8A. Half patients carried a 1q21.1 deletion and one of the two known hypomorphic variants. Four novel noncoding variants of RBM8A were identified in the remaining patients. We developed experimental models enabling their functional characterization in vitro. Two variants, located respectively in the 5′‐untranslated region (5′‐UTR) and 3′‐UTR regions, are responsible for a diminished expression whereas two intronic variants alter splicing. Our results bring new insights into the molecular knowledge of TAR syndrome and enabled us to propose genetic counseling for patients' families.
Island birds that were victims of anthropic extinctions were often more specialist species, having evolved their most distinctive features in isolation, making the study of fossil insular birds most ...interesting. Here we studied a fossil cranium of the 'giant' extinct scops owl Otus murivorus from Rodrigues Island (Mascarene Islands, southwestern Indian Ocean), to determine any potential unique characters. The fossil and extant strigids were imaged through X-ray microtomography, providing 3D views of external and internal (endocast, inner ear) cranial structures. Geometric morphometrics and analyses of traditional measurements yielded new information about the Rodrigues owl's evolution and ecology. Otus murivorus exhibits a 2-tier "lag behind" phenomenon for cranium and brain evolution, both being proportionately small relative to increased body size. It also had a much more developed olfactory bulb than congeners, indicating an unexpectedly developed olfactory sense, suggesting a partial food scavenging habit. In addition, O. murivorus had the eyes placed more laterally than O. sunia, the species from which it was derived, probably a side effect of a small brain; rather terrestrial habits; probably relatively fearless behavior; and a less vertical posture (head less upright) than other owls (this in part an allometric effect of size increase). These evolutionary features, added to gigantism and wing reduction, make the extinct Rodrigues owl's evolution remarkable, and with multiple causes.
Perfluoropolyalkylethers (PFPAEs) are a class of fluorinated polymers having −OCF2–, −OCF2CF2–, and −OCF2CF(CF3)– as common chain units. The ether linkages distinguish them from other famous ...fluorinated polymers such as poly(tetrafluoroethylene). Their higher mobility highlighted by below zero glass transition temperatures permit them to be noncrystalline, which makes them easy to use for many applications. They possess interesting tribological properties, combined with an excellent thermal and chemical stability, make them very useful as lubricants. However, after chemical modifications, they also demonstrated to be very useful in numerous applications as surfactants, electrolytes, high performance coatings, vitrimers, or microfluidic devices, to give a few examples. This Perspective aims to summarize all the chemical modifications reported on these PFPAEs to provide a new insight into their potential utility in emerging fields. Indeed, the end group can modulate the properties of PFPAE-based materials such as lubricity, superhydrophobicity, biofouling, antibacterial activity, amphiphilicity, and the ability to react further with comonomers under photochemical and thermal processes. It can also modulate their intrinsic properties such as viscosity and solubility in common organic solvents. The chemical modifications are sorted in five main parts: the condensation reactions, the nucleophilic reactions, the click chemistry reactions, the radical reactions, and finally reactions going through other mechanisms or requiring a multistep process. They can be employed as such or for further polymerization processes depending on the targeted application. Examples of applications are thoroughly described to demonstrate their current usefulness and to help provide direction for their future use.
Many model inversion problems occur in industry. These problems consist in finding the set of parameter values such that a certain quantity of interest respects a constraint, for example remains ...below a threshold. In general, the quantity of interest is the output of a simulator, costly in computation time. An effective way to solve this problem is to replace the simulator by a Gaussian process regression, with an experimental design enriched sequentially by a well chosen acquisition criterion. Different inversion-adapted criteria exist such as the Bichon criterion (also known as expected feasibility function) and deviation number . There also exist a class of enrichment strategies (stepwise uncertainty reduction—SUR) which select the next point by measuring the expected uncertainty reduction induced by its selection. In this paper we propose a SUR version of the Bichon criterion. An explicit formulation of the criterion is given and test comparisons show good performances on classical test functions.
The majority of inherited retinal degenerations converge on the phenotype of photoreceptor cell death. Second- and third-order neurons are spared in these diseases, making it possible to restore ...retinal light responses using optogenetics. Viral expression of channelrhodopsin in the third-order neurons under ubiquitous promoters was previously shown to restore visual function, albeit at light intensities above illumination safety thresholds. Here, we report (to our knowledge, for the first time) activation of macaque retinas, up to 6 months post-injection, using channelrhodopsin-Ca2+-permeable channelrhodopsin (CatCh) at safe light intensities. High-level CatCh expression was achieved due to a new promoter based on the regulatory region of the gamma-synuclein gene (SNCG) allowing strong expression in ganglion cells across species. Our promoter, in combination with clinically proven adeno-associated virus 2 (AAV2), provides CatCh expression in peri-foveolar ganglion cells responding robustly to light under the illumination safety thresholds for the human eye. On the contrary, the threshold of activation and the proportion of unresponsive cells were much higher when a ubiquitous promoter (cytomegalovirus CMV) was used to express CatCh. The results of our study suggest that the inclusion of optimized promoters is key in the path to clinical translation of optogenetics.
Vision restoration using microbial opsins has substantial clinical potential; however, it requires high-level expression of a foreign protein in the patient’s eyes. Our study shows the feasibility of obtaining safe and functional expression in primates using a cell-specific promoter and provides the basis for further clinical development of this optogenetic strategy.
Highlights • Freezing of gait was related to hypometabolism of premotor area during actual gait. • Freezers presented a hypermetabolism of the posterior parietal cortex during gait. • Parietofrontal ...network was involved in freezing phenomenon. • Basal ganglia overactivation during gait was observed in freezers patients. • The balance between external and internal signals may fail during freezing.
Introduction
Soluble markers of B cell activation are interesting diagnostic and prognostic tools in autoimmune diseases. Data in systemic sclerosis (SSc) are scarce and few studies focused on their ...association with disease characteristics.
Methods
1. Serum levels of 14 B cell biomarkers (β2-microglobulin, rheumatoid factor (RF), immunoglobulins (Ig) G, IgA, IgM, BAFF, APRIL, soluble (s)TACI, sBCMA sCD21, sCD23, sCD25, sCD27, CXCL13) were measured in SSc patients and healthy controls (HC). 2. Associations between these biomarkers and SSc characteristics were assessed. 3. The pathophysiological relevance of identified associations was explored by studying protein production in B cell culture supernatant.
Results
In a discovery panel of 80 SSc patients encompassing the broad spectrum of disease manifestations, we observed a higher frequency of RF positivity, and increased levels of β2-microglobulin, IgG and CXCL13 compared with HC. We found significant associations between several biomarkers and SSc characteristics related to disease phenotype, activity and severity. Especially, serum IgG levels were associated with pulmonary hypertension (PH); β2-microglobulin with Nt-pro-BNP and DLCO; and BAFF with peak tricuspid regurgitation velocity (TRV). In a validation cohort of limited cutaneous SSc patients without extensive ILD, we observed lower serum IgG levels, and higher β2-microglobulin, sBCMA, sCD23 and sCD27 levels in patients with pulmonary arterial hypertension (PAH). BAFF levels strongly correlated with Nt-pro-BNP levels, FVC/DLCO ratio and peak TRV in SSc-PAH patients. Cultured SSc B cells showed increased production of various angiogenic factors (angiogenin, angiopoietin-1, VEGFR-1, PDGF-AA, MMP-8, TIMP-1, L-selectin) and decreased production of angiopoietin-2 compared to HC.
Conclusion
Soluble markers of B cell activation could be relevant tools to assess organ involvements, activity and severity in SSc. Their associations with PAH could plead for a role of B cell activation in the pathogenesis of pulmonary microangiopathy. B cells may contribute to SSc vasculopathy through production of angiogenic mediators.
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