Antiviral CD8+ T-cell immune responses are impaired by cigarette smoke and in COPD

BACKGROUND

Virus infections drive COPD exacerbations and progression. Antiviral immunity centres on the activation of virus-specific CD8+ T-cells by viral epitopes presented on major histocompatibility complex (MHC) class I molecules of infected cells. These epitopes are generated by the immunoproteasome, a specialised intracellular protein degradation machine, which is induced by antiviral cytokines in infected cells.

METHODS

We analysed the effects of cigarette smoke on cytokine- and virus-mediated induction of the immunoproteasome in vitro, ex vivo and in vivo using RNA and Western blot analyses. CD8+ T-cell activation was determined in co-culture assays with cigarette smoke-exposed influenza A virus (IAV)-infected cells. Mass-spectrometry-based analysis of MHC class I-bound peptides uncovered the effects of cigarette smoke on inflammatory antigen presentation in lung cells. IAV-specific CD8+ T-cell numbers were determined in patients' peripheral blood using tetramer technology.

RESULTS

Cigarette smoke impaired the induction of the immunoproteasome by cytokine signalling and viral infection in lung cells in vitro, ex vivo and in vivo. In addition, cigarette smoke altered the peptide repertoire of antigens presented on MHC class I molecules under inflammatory conditions. Importantly, MHC class I-mediated activation of IAV-specific CD8+ T-cells was dampened by cigarette smoke. COPD patients exhibited reduced numbers of circulating IAV-specific CD8+ T-cells compared to healthy controls and asthmatics.

CONCLUSION

Our data indicate that cigarette smoke interferes with MHC class I antigen generation and presentation and thereby contributes to impaired activation of CD8+ T-cells upon virus infection. This adds important mechanistic insight on how cigarette smoke mediates increased susceptibility of smokers and COPD patients to viral infections.

Creating a list of word alignments from parallel Russian simplification data

This work describes the development of a list of monolingual word alignments taken from parallel Russian simplification data. This word lists can be used in such lexical simplification tasks as rule-based simplification applications and lexically constrained decoding for neural machine translation models. Moreover, they constitute a valuable source of information for developing educational materials for teaching Russian as a second/foreign language. In this work, a word list was compiled automatically and post-edited by human experts. The resulting list contains 1409 word pairs in which each “complex” word has an equivalent “simpler” (shorter, more frequent, modern, international) synonym. We studied the contents of the word list by comparing the frequencies of the words in the pairs and their levels in the special CEFR-graded vocabulary lists for learners of Russian as a foreign language. The evaluation demonstrated that lexical simplification by means of single-word synonym replacement does not occur often in the adapted texts. The resulting list also illustrates the peculiarities of the lexical simplification task for L2 learners, such as the choice of a less frequent but international word.

A Comparative Study of Educational Texts for Native, Foreign, and Bilingual Young Speakers of Russian: Are Simplified Texts Equally Simple?

Studies on simple language and simplification are often based on datasets of texts, either for children or learners of a second language. In both cases, these texts represent an example of simple language, but simplification likely involves different strategies. As such, this data may not be entirely homogeneous in terms of text simplicity. This study investigates linguistic properties and specific simplification strategies used in Russian texts for primary school children with different language backgrounds and levels of language proficiency. To explore the structure and variability of simple texts for young readers of different age groups, we have trained models for multiclass and binary classification. The models were based on quantitative features of texts. Subsequently, we evaluated the simplification strategies applied to readers of the same age with different linguistic backgrounds. This study is particularly relevant for the Russian language material, where the concept of easy and plain language has not been sufficiently investigated. The study revealed that the three types of texts cannot easily be distinguished from each other by judging the performance of multiclass models based on various quantitative features. Therefore, it can be said that texts of all types exhibit a similar level of accessibility to young readers. In contrast, binary classification tasks demonstrated better results, especially in the R-native vs. non R-native track (with 0.78 F1-score), these results may indicate that the strategies used for adapting or creating texts for each type of audience are different.

Machine learning-enabled phenotyping for GWAS and TWAS of WUE traits in 869 field-grown sorghum accessions

Sorghum (Sorghum bicolor) is a model C4 crop made experimentally tractable by extensive genomic and genetic resources. Biomass sorghum is studied as a feedstock for biofuel and forage. Mechanistic modeling suggests that reducing stomatal conductance (gs) could improve sorghum intrinsic water use efficiency (iWUE) and biomass production. Phenotyping to discover genotype-to-phenotype associations remains a bottleneck in understanding the mechanistic basis for natural variation in gs and iWUE. This study addressed multiple methodological limitations. Optical tomography and a machine learning tool were combined to measure stomatal density (SD). This was combined with rapid measurements of leaf photosynthetic gas exchange and specific leaf area (SLA). These traits were the subject of genome-wide association study and transcriptome-wide association study across 869 field-grown biomass sorghum accessions. The ratio of intracellular to ambient CO2 was genetically correlated with SD, SLA, gs, and biomass production. Plasticity in SD and SLA was interrelated with each other and with productivity across wet and dry growing seasons. Moderate-to-high heritability of traits studied across the large mapping population validated associations between DNA sequence variation or RNA transcript abundance and trait variation. A total of 394 unique genes underpinning variation in WUE-related traits are described with higher confidence because they were identified in multiple independent tests. This list was enriched in genes whose Arabidopsis (Arabidopsis thaliana) putative orthologs have functions related to stomatal or leaf development and leaf gas exchange, as well as genes with nonsynonymous/missense variants. These advances in methodology and knowledge will facilitate improving C4 crop WUE.

Machine learning-enabled phenotyping for GWAS and TWAS of WUE traits in 869 field-grown sorghum accessions

Sorghum (Sorghum bicolor) is a model C4 crop made experimentally tractable by extensive genomic and genetic resources. Biomass sorghum is studied as a feedstock for biofuel and forage. Mechanistic modeling suggests that reducing stomatal conductance (gs) could improve sorghum intrinsic water use efficiency (iWUE) and biomass production. Phenotyping to discover genotype-to-phenotype associations remains a bottleneck in understanding the mechanistic basis for natural variation in gs and iWUE. This study addressed multiple methodological limitations. Optical tomography and a machine learning tool were combined to measure stomatal density (SD). This was combined with rapid measurements of leaf photosynthetic gas exchange and specific leaf area (SLA). These traits were the subject of genome-wide association study and transcriptome-wide association study across 869 field-grown biomass sorghum accessions. The ratio of intracellular to ambient CO2 was genetically correlated with SD, SLA, gs, and biomass production. Plasticity in SD and SLA was interrelated with each other and with productivity across wet and dry growing seasons. Moderate-to-high heritability of traits studied across the large mapping population validated associations between DNA sequence variation or RNA transcript abundance and trait variation. A total of 394 unique genes underpinning variation in WUE-related traits are described with higher confidence because they were identified in multiple independent tests. This list was enriched in genes whose Arabidopsis (Arabidopsis thaliana) putative orthologs have functions related to stomatal or leaf development and leaf gas exchange, as well as genes with nonsynonymous/missense variants. These advances in methodology and knowledge will facilitate improving C4 crop WUE.

FRI0386 EARLY OSTEOARTHRITIS: IS ASYMPTOMATIC CLINICAL COURSE REAL?

Background:

Osteoarthritis (OA) is the leading cause of disability among all RMDs. Early diagnosis of OA is complicated. So, there is an absence of clear markers of the diagnosis of OA, and this issue is now being discussed.

Objectives:

The aim of this study is to examine relatively healthy individuals without symptoms in order to evaluate MR-markers of early OA of the knee.

Methods:

We included 29 relatively healthy individuals. 55,17% (n=16) were women. Median age was 35 (32-41) years. They didn’t have any complaints, according to the preliminary criteria of early OA, symptoms of OA (1), didn’t have any significant concomitant diseases and elevated ESR, CRP. The exclusion criteria were previous trauma, orthopedic surgery, X-Ray signs of OA. MRI was performed on 1,5 Tl Siemens Magnetom Essenza. WORMS-scale was used to evaluate the knee joint structures.

Results:

In all examined joints we observed small changes characteristic of symptomatic OA (osteophytes, cartilage damage etc.). In 4 knees we found undamaged cartilage (0 points). In 5 knees we observed cartilage damage >=4 points with marrow abnormality. In the Table 1 we present the frequency of any abnomaly (>=1 points) in each parameter present in examined joints. The most commonly asymptomatic changes were observed in the patellofemoral joint. Small osteophytes were the most common changes.

Table 1.

Number of examined knee joints with different anomalies according to WORMS (>=1 point).

ParameterMFTJ (percent, total)LFTJ, (percent, total)PFJ (percent, total)S-region, (percent, total)Total, (percent, total)Cartilage19,44% (n=7)19,44% (n=7)75,00% (n=27)-83,33% (n=30)Marrow abnormality0,00%2,78% (n=1)0,00%13,89% (n=5)16,67%(n=6)Bone cysts0,00%0,00%0,00%0,00%0,00%Bone attrition66,67% (n=24)0,00%--66,67% (n=24)Osteophytes88,89% (n=32)86,11% (n=31)97,22% (n=35)-100,00% (n=36)Menisci0,00%2,78% (n=1)--2,78% (n=1)Ligaments----0,00%Synovitis----33,33% (n=12)Total––––100,00% (n=36)

Besides, we calculated mean points in each parameter in the scale and compared it with the maximum score in this parameter (in percent). Table 2 shows the results. The most severe change was bone attrition.

Table 2.

Mean points of different WORMS parameters in examined knee joints.

ParameterMFTJ (percent, total)LFTJ, (percent, total)PFJ (percent, total)S-region, (percent, total)Total, (percent, total)Cartilage1,30%1,02%7,64%-2,91%Marrow abnormality0,00%0,37%0,00%4,63%0,31%Bone cysts0,00%0,00%0,00%0,00%0,00%Bone attrition15,37%0,00%0,00%-1,75%Osteophytes6,59%5,48%8,33%-6,69%Menisci0,00%0,93%--0,46%Ligaments----0,00%Synovitis----12,04%Total----3,61%

We didn’t observe asymptomatic lesions in the medial meniscus, marrow abnormality in MFTJ and LFTJ, subchondral cysts in any location, ligament lesions. Despite minimal osteophytes almost in all individuals, they didn’t have any clinical features of knee OA.

Conclusion:

MRI of the knee joints in the cohort of young relatively healthy individuals without clinical features of OA revealed irreversible structural changes characteristic of symptomatic OA. There is no association between symptoms and structural damage. Based on these, we can make an assumption about asymptomatic stage of OA. In order to distinguish between definitions of early asymptomatic OA as a disease onset and asymptomatic structural changes as reflection of metabolic disorders it is necessary to follow up and to perform an in-depth examination of these individuals.

References:

[1]Migliore, A., Scirè, C.A., Carmona, L.et al.The challenge of the definition of early symptomatic knee osteoarthritis: a proposal of criteria and red flags from an international initiative promoted by the Italian Society for Rheumatology.Rheumatol Int37, 1227–1236 (2017).

Disclosure of Interests:

Natalia Martusevich Shareholder of: k, Svetlana Duben: None declared, Alexander Aleshkevich: None declared, Alena Dmitrieva: None declared, Tatsiana Bondar: None declared, Katsiarina Gudkevich: None declared

Statins lower plasma and lymphocyte ubiquinol/ubiquinone without affecting other antioxidants and PUFA

It has been shown that treating hypercholesterolemic patients (HPC) with statins leads to a decrease, at least in plasma, not only in cholesterol, but also in important non-sterol compounds such as ubiquinone (CoQ10), and possibly dolichols, that derive from the same biosynthetic pathway. Plasma CoQ10 decrease might result in impaired antioxidant protection, therefore leading to oxidative stress. In the present paper we investigated the levels in plasma, lymphocytes and erythrocytes, of ubiquinol and ubiquinone, other enzymatic and non-enzymatic lipophilic and hydrophilic antioxidants, polyunsaturated fatty acids of phosfolipids and cholesterol ester fractions, as well as unsaturated lipid and protein oxidation in 42 hypercholesterolemic patients treated for 3 months. The patients were treated with different doses of 3 different statins, i.e. atorvastatin 10 mg (n = 10) and 20 mg (n = 7), simvastatin, 10 mg (n = 5) and 20 mg (n = 10), and pravastatin, 20 mg (n = 5) and 40 mg (n = 5). Simvastatin, atorvastatin and pravastatin produced a dose dependent plasma depletion of total cholesterol (t-CH), LDL-C, CoQ10H2, and CoQ10, without affecting the CoQ10H2/CoQ10 ratio. The other lipophilic antioxidants (d-RRR-alpha-tocopherol-vit E-, gamma-tocopherol, vit A, lycopene, and beta-carotene), hydrophilic antioxidants (vit C and uric acid), as well as, TBA-RS and protein carbonyls were also unaffected. Similarly the erythrocyte concentrations of GSH and PUFA, and the activities of enzymatic antioxidants (Cu,Zn-SOD, GPx, and CAT) were not significantly different from those of the patients before therapy. In lymphocytes the reduction concerned CoQ10H2, CoQ10, and vit E; other parameters were not investigated. The observed decline of the levels of CoQ10H2 and CoQ10 in plasma and of CoQ10H2, CoQ10 and vit E in lymphocytes following a 3 month statin therapy might lead to a reduced antioxidant capacity of LDL and lymphocytes, and probably of tissues such as liver, that have an elevated HMG-CoA reductase enzymatic activity. However, this reduction did not appear to induce a significant oxidative stress in blood, since the levels of the other antioxidants, the pattern of PUFA as well as the oxidative damage to PUFA and proteins resulted unchanged. The concomitant administration of ubiquinone with statins, leading to its increase in plasma, lymphocytes and liver may cooperate in counteracting the adverse effects of statins, as already pointed out by various authors on the basis of human and animal studies.