Associations of BCL-2 (RS17759659), CTLA-4 (RS231775), APO-1/FAS (RS2234767) genes polymorphisms with activity of proliferation and apoptosis in thyroid tissue of patients with nodular forms of goiter combined with autoimmune thyroiditis and thyroid adenoma

The study of apoptosis and proliferative activity in the thyroid gland (TG) tissue of patients with nodular goiter and autoimmune thyroiditis (NGAIT) and thyroid adenoma (TA) is based on the expression/density of Fas/FasL, BCL-2, p53, and Ki-67 markers assessment depending on the genetic polymorphisms of BCL-2 (rs17759659), CTLA-4 (rs231775) and APO-1/Fas (rs2234767) genes.Several mechanisms of thyroid cells' programmed killing are activated in NGAIT and TA with domination of Fas-induced apoptosis, which strongly associates with the BCL-2 gene's (rs17759659) promoter (F=25.33; p<0.001) and almost six fold weaker associates with the CTLA-4 gene's (rs231775) promoter (F=4.23, p=0.017). Factors that decrease the likelihood of NGAIT and TA regardless of the CTLA-4 (rs231775) and APO-1/Fas (rs2234767) genes' genotypes are the high Ki-67 density and reduction of cells containing p53 or BCL-2 proteins (OR=0.07-0.17; 95% CI OR: 0.03-0.36; p<0.001, and OR=0.08-0.11; 95% CI OR: 0.02-0.31; p<0.001, re­spectively). High expression of surface Fas and FasL in lymphoid infiltration and de­struction of thyroid cells (stronger in GG-genotype carriers of the BCL-2 gene by 18.54% (pAA=0.043) and 36.18% (pAG=0.018), respectively) indicates the initiation of the external pathway of apoptosis through the caspase mechanism (effector caspase- 8)

Constant regulation for stable CD8 T-cell functional avidity and its possible implications for cancer immunotherapy.

The functional avidity (FA) of cytotoxic CD8 T cells impacts strongly on their functional capabilities and correlates with protection from infection and cancer. FA depends on TCR affinity, downstream signaling strength, and TCR affinity-independent parameters of the immune synapse, such as costimulatory and inhibitory receptors. The functional impact of coreceptors on FA remains to be fully elucidated. Despite its importance, FA is infrequently assessed and incompletely understood. There is currently no consensus as to whether FA can be enhanced by optimized vaccine dose or boosting schedule. Recent findings suggest that FA is remarkably stable in vivo, possibly due to continued signaling modulation of critical receptors in the immune synapse. In this review, we provide an overview of the current knowledge and hypothesize that in vivo, codominant T cells constantly "equalize" their FA for similar function. We present a new model of constant FA regulation, and discuss practical implications for T-cell-based cancer immunotherapy

Dissecting the role of single nucleotide polymorphism of lymphotoxin beta gene during pig domestication using bioinformatic and experimental approaches

Studies of wild and laboratory animals have revealed a trade-off between reproductive success and immunity. Therefore, it is likely that domestication favored selection of individuals with high reproductive performance but low immunity. The low responsiveness of the immune system could become hereditary through fixation of genes with “unfavorable” mutations in populations. The objectives of this work are: 1) determination of frequencies of genotypes and alleles of the rs340283541 SNP in the gene for the lymphotoxin beta (LTB) cytokine in pigs of domestic breeds and wild boars; 2) investigation of the expression of LTB mRNA in minipigs with different genotypes, and 3) bioinformational analysis of the putative functional role of the SNP. The frequency of the GG genotype in the wild boar sample was significantly lower than in the pooled sample of domestic pigs. The LTB mRNA expression rate in the lymph node of minipigs with genotype GG tended to increase (p < 0.06) in comparison with carriers o allele A. The rs340283541 SNP occurs in a DNA motif highly conservative among 11 mammalian species; thus, it may be of functional significance. Context analysis shows that allele A has putative binding sites for  transcription factors BRN-2 and AP-1, whereas allele G has binding sites for transcription factors RFX1, ISGF3 (site ISRE), and USF expressed in cells of the immune system. Thus, pig domestication was accompanied by an increase in the frequency of the GG genotype for the rs340283541 SNP, occurring in the 3’ region of the LTB gene. It is likely that the GG genotype is associated with elevated LTB mRNA expression in the lymph node tissue. This increase may be related to the formation of binding sites for RFX1, ISRE, and USF and/or disruption of binding sites for BRN-2 and AP-1. A linkage disequilibrium between rs340283541 and another functionally significant mutation in LTB is also conceivable

Effective transcription factor binding site prediction using a combination of optimization, a genetic algorithm and discriminant analysis to capture distant interactions

<p>Abstract</p> <p>Background</p> <p>Reliable transcription factor binding site (TFBS) prediction methods are essential for computer annotation of large amount of genome sequence data. However, current methods to predict TFBSs are hampered by the high false-positive rates that occur when only sequence conservation at the core binding-sites is considered.</p> <p>Results</p> <p>To improve this situation, we have quantified the performance of several Position Weight Matrix (PWM) algorithms, using exhaustive approaches to find their optimal length and position. We applied these approaches to bio-medically important TFBSs involved in the regulation of cell growth and proliferation as well as in inflammatory, immune, and antiviral responses (NF-κB, ISGF3, IRF1, STAT1), obesity and lipid metabolism (PPAR, SREBP, HNF4), regulation of the steroidogenic (SF-1) and cell cycle (E2F) genes expression. We have also gained extra specificity using a method, entitled SiteGA, which takes into account structural interactions within TFBS core and flanking regions, using a genetic algorithm (GA) with a discriminant function of locally positioned dinucleotide (LPD) frequencies.</p> <p>To ensure a higher confidence in our approach, we applied resampling-jackknife and bootstrap tests for the comparison, it appears that, optimized PWM and SiteGA have shown similar recognition performances. Then we applied SiteGA and optimized PWMs (both separately and together) to sequences in the Eukaryotic Promoter Database (EPD). The resulting SiteGA recognition models can now be used to search sequences for BSs using the web tool, SiteGA.</p> <p>Analysis of dependencies between close and distant LPDs revealed by SiteGA models has shown that the most significant correlations are between close LPDs, and are generally located in the core (footprint) region. A greater number of less significant correlations are mainly between distant LPDs, which spanned both core and flanking regions. When SiteGA and optimized PWM models were applied together, this substantially reduced false positives at least at higher stringencies.</p> <p>Conclusion</p> <p>Based on this analysis, SiteGA adds substantial specificity even to optimized PWMs and may be considered for large-scale genome analysis. It adds to the range of techniques available for TFBS prediction, and EPD analysis has led to a list of genes which appear to be regulated by the above TFs.</p

Myocardial Tissue Remodeling in Adolescent Obesity

Background: Childhood obesity is a significant risk factor for cardiovascular disease in adulthood. Although ventricular remodeling has been reported in obese youth, early tissue‐level markers within the myocardium that precede organ‐level alterations have not been described. Methods and Results: We studied 21 obese adolescents (mean age, 17.7±2.6 years; mean body mass index [BMI], 41.9±9.5 kg/m2, including 11 patients with type 2 diabetes [T2D]) and 12 healthy volunteers (age, 15.1±4.5 years; BMI, 20.1±3.5 kg/m2) using biomarkers of cardiometabolic risk and cardiac magnetic resonance imaging (CMR) to phenotype cardiac structure, function, and interstitial matrix remodeling by standard techniques. Although left ventricular ejection fraction and left atrial volumes were similar in healthy volunteers and obese patients (and within normal body size‐adjusted limits), interstitial matrix expansion by CMR extracellular volume fraction (ECV) was significantly different between healthy volunteers (median, 0.264; interquartile range [IQR], 0.253 to 0.271), obese adolescents without T2D (median, 0.328; IQR, 0.278 to 0.345), and obese adolescents with T2D (median, 0.376; IQR, 0.336 to 0.407; P=0.0001). ECV was associated with BMI for the entire population (r=0.58, P<0.001) and with high‐sensitivity C‐reactive protein (r=0.47, P<0.05), serum triglycerides (r=0.51, P<0.05), and hemoglobin A1c (r=0.76, P<0.0001) in the obese stratum. Conclusions: Obese adolescents (particularly those with T2D) have subclinical alterations in myocardial tissue architecture associated with inflammation and insulin resistance. These alterations precede significant left ventricular hypertrophy or decreased cardiac function

Protection of Melanized Cryptococcus neoformans from Lethal Dose Gamma Irradiation Involves Changes in Melanin's Chemical Structure and Paramagnetism

Certain fungi thrive in highly radioactive environments including the defunct Chernobyl nuclear reactor. Cryptococcus neoformans (C. neoformans), which uses L-3,4-dihydroxyphenylalanine (L-DOPA) to produce melanin, was used here to investigate how gamma radiation under aqueous aerobic conditions affects the properties of melanin, with the aim of gaining insight into its radioprotective role. Exposure of melanized fungal cell in aqueous suspensions to doses of γ-radiation capable of killing 50 to 80% of the cells did not lead to a detectable loss of melanin integrity according to EPR spectra of melanin radicals. Moreover, upon UV-visible (Xe-lamp) illumination of melanized cells, the increase in radical population was unchanged after γ-irradiation. Gamma-irradiation of frozen cell suspensions and storage of samples for several days at 77 K however, produced melanin modification noted by a reduced radical population and reduced photoresponse. More direct evidence for structural modification of melanin came from the detection of soluble products with absorbance maxima near 260 nm in supernatants collected after γ-irradiation of cells and cell-free melanin. These products, which include thiobarbituric acid (TBA)-reactive aldehydes, were also generated by Fenton reagent treatment of cells and cell-free melanin. In an assay of melanin integrity based on the metal (Bi+3) binding capacity of cells, no detectable loss in binding was detected after γ-irradiation. Our results show that melanin in C. neoformans cells is susceptible to some damage by hydroxyl radical formed in lethal radioactive aqueous environments and serves a protective role in melanized fungi that involves sacrificial breakdown

Sheddable Coatings for Long-Circulating Nanoparticles

Nanoparticles, such as liposomes, polymeric micelles, lipoplexes and polyplexes are frequently studied as targeted drug carrier systems. The ability of these particles to circulate in the bloodstream for a prolonged period of time is often a prerequisite for successful targeted delivery. To achieve this, hydrophilic ‘stealth’ polymers, such as poly(ethylene glycol) (PEG), are used as coating materials. Such polymers shield the particle surface and thereby reduce opsonization by blood proteins and uptake by macrophages of the mononuclear phagocyte system. Yet, after localizing in the pathological site, nanoparticles should deliver their contents in an efficient manner to achieve a sufficient therapeutic response. The polymer coating, however, may hinder drug release and target cell interaction and can therefore be an obstacle in the realization of the therapeutic response. Attempts have been made to enhance the therapeutic efficacy of sterically stabilized nanoparticles by means of shedding, i.e. a loss of the coating after arrival at the target site. Such an ‘unmasking’ process may facilitate drug release and/or target cell interaction processes. This review presents an overview of the literature regarding different shedding strategies that have been investigated for the preparation of sterically stabilized nanoparticulates. Detach mechanisms and stimuli that have been used are described