Pre-clinical and clinical aspects of peptide-based vaccine against human solid tumors

Peptides deriving from tumor-associated antigens and recognized by patient T cells have been firstly defined in the early 90's, and then used as vaccine in animal models and in cancer patients. Early trials showed a variable, often even high frequency of patients developing peptide-specific T-cell mediated immune response usually accompanied by a lower frequency of clinical response. Modified, long peptides could be synthesized with a higher in vitro binding to the corresponding HLA allele that only seldom translated into a clear improvement in the tumor response. However, we show here that more recent studies of multipeptide-based vaccines resulted in a higher and more robust T cell response causing also a more effective clinical response particularly in melanoma and prostate cancer patients. In this article, we also used some of the recent patents describing different inventions related to pre-clinical and clinical aspects of peptide based vaccines against human solid tumors.     

The molecular basis for the broad substrate specificity of human sulfotransferase 1A1

Cytosolic sulfotransferases (SULTs) are mammalian enzymes that detoxify a wide variety of chemicals through the addition of a sulfate group. Despite extensive research, the molecular basis for the broad specificity of SULTs is still not understood. Here, structural, protein engineering and kinetic approaches were employed to obtain deep understanding of the molecular basis for the broad specificity, catalytic activity and substrate inhibition of SULT1A1. We have determined five new structures of SULT1A1 in complex with different acceptors, and utilized a directed evolution approach to generate SULT1A1 mutants with enhanced thermostability and increased catalytic activity. We found that active site plasticity enables binding of different acceptors and identified dramatic structural changes in the SULT1A1 active site leading to the binding of a second acceptor molecule in a conserved yet non-productive manner. Our combined approach highlights the dominant role of SULT1A1 structural flexibility in controlling the specificity and activity of this enzyme.     

Effect of the cannabinoid receptor-1 antagonist rimonabant on inflammation in mice with diet-induced obesity

We studied whether cannabinoid receptor (CB1) blockade with rimonabant has an anti-inflammatory effect in obese mice, and whether this effect depends on weight loss and/or diet consumption. High-fat diet (HFD)-induced obese mice were treated orally with rimonabant (HFD-R) or vehicle (HFD-V) for 4 weeks. Paired-feeding was conducted in two additional groups of obese mice to achieve either the same body weight (HFD-BW) or the same HFD intake (HFD DI) as HFD-R. All these groups of mice were maintained on HFD throughout, with mice on normal diet (ND) throughout as lean controls. Rimonabant treatment of obese mice induced marked diet-intake reduction and weight loss during the first week, which was followed by maintenance of low body weight but not diet-intake reduction. Lower HFD intake was required to reach the same degree of weight loss in HFD-BW. HFD-DI had similar weight loss initially, but then started to gain weight, reaching a higher body weight than HFD-R. Despite the same degree of weight loss, HFD-R had less fat mass and lower adipogenic gene expression than HFD-BW. Compared to HFD-V or HFD-DI, HFD-R had reduced inflammation in adipose tissue (AT) and/or liver indicated primarily by lower monocyte chemoattractant protein-1 (MCP-1) levels. However, MCP-1 levels were not significantly different between HFD-R and HFD-BW. In vitro incubation of rimonabant with AT explants did not change MCP-1 levels. Thus, rimonabant induced weight loss in obese mice by diet-intake-dependent and -independent fashions. Rimonabant decreased inflammation in obese mice, possibly through a primary effect on weight reduction.     

Do Women's Voices Provide Cues of the Likelihood of Ovulation? The Importance of Sampling Regime

The human voice provides a rich source of information about individual attributes such as body size, developmental stability and emotional state. Moreover, there is evidence that female voice characteristics change across the menstrual cycle. A previous study reported that women speak with higher fundamental frequency (F0) in the high-fertility compared to the low-fertility phase. To gain further insights into the mechanisms underlying this variation in perceived attractiveness and the relationship between vocal quality and the timing of ovulation, we combined hormone measurements and acoustic analyses, to characterize voice changes on a day-to-day basis throughout the menstrual cycle. Voice characteristics were measured from free speech as well as sustained vowels. In addition, we asked men to rate vocal attractiveness from selected samples. The free speech samples revealed marginally significant variation in F0 with an increase prior to and a distinct drop during ovulation. Overall variation throughout the cycle, however, precluded unequivocal identification of the period with the highest conception risk. The analysis of vowel samples revealed a significant increase in degree of unvoiceness and noise-to-harmonic ratio during menstruation, possibly related to an increase in tissue water content. Neither estrogen nor progestogen levels predicted the observed changes in acoustic characteristics. The perceptual experiments revealed a preference by males for voice samples recorded during the pre-ovulatory period compared to other periods in the cycle. While overall we confirm earlier findings in that women speak with a higher and more variable fundamental frequency just prior to ovulation, the present study highlights the importance of taking the full range of variation into account before drawing conclusions about the value of these cues for the detection of ovulation.     

Mapping the organization of axis of motion selective features in human area MT using high-field fMRI

Functional magnetic resonance imaging (fMRI) at high magnetic fields has made it possible to investigate the columnar organization of the human brain in vivo with high degrees of accuracy and sensitivity. Until now, these results have been limited to the organization principles of early visual cortex (V1). While the middle temporal area (MT) has been the first identified extra-striate visual area shown to exhibit a columnar organization in monkeys, evidence of MT's columnar response properties and topographic layout in humans has remained elusive. Research using various approaches suggests similar response properties as in monkeys but failed to provide direct evidence for direction or axis of motion selectivity in human area MT. By combining state of the art pulse sequence design, high spatial resolution in all three dimensions (0.8 mm isotropic), optimized coil design, ultrahigh field magnets (7 Tesla) and novel high resolution cortical grid sampling analysis tools, we provide the first direct evidence for large-scale axis of motion selective feature organization in human area MT closely matching predictions from topographic columnar-level simulations.     

Hyperspectral computed tomographic imaging spectroscopy of vascular oxygen gradients in the rabbit retina in vivo

Diagnosis of retinal vascular diseases depends on ophthalmoscopic findings that most often occur after severe visual loss (as in vein occlusions) or chronic changes that are irreversible (as in diabetic retinopathy). Despite recent advances, diagnostic imaging currently reveals very little about the vascular function and local oxygen delivery. One potentially useful measure of vascular function is measurement of hemoglobin oxygen content. In this paper, we demonstrate a novel method of accurately, rapidly and easily measuring oxygen saturation within retinal vessels using in vivo imaging spectroscopy. This method uses a commercially available fundus camera coupled to two-dimensional diffracting optics that scatter the incident light onto a focal plane array in a calibrated pattern. Computed tomographic algorithms are used to reconstruct the diffracted spectral patterns into wavelength components of the original image. In this paper the spectral components of oxy- and deoxyhemoglobin are analyzed from the vessels within the image. Up to 76 spectral measurements can be made in only a few milliseconds and used to quantify the oxygen saturation within the retinal vessels over a 10-15 degree field. The method described here can acquire 10-fold more spectral data in much less time than conventional oximetry systems (while utilizing the commonly accepted fundus camera platform). Application of this method to animal models of retinal vascular disease and clinical subjects will provide useful and novel information about retinal vascular disease and physiology.     

Fiber-based liquid-phase micro-extraction of mebeverine enantiomers followed by chiral high-performance liquid chromatography analysis and its application to pharmacokinetics study in rat plasma

The applicability of two-phase liquid-phase micro-extraction (LPME) in porous hollow polypropylene fiber for the sample preparation and the stereoselective pharmacokinetics of mebeverine (MEB) enantiomers (an antispasmodic drug) in rat after intramuscular administration were studied. Plasma was assayed for MEB enantiomer concentrations using stereospecific high-performance liquid chromatography with ultraviolet detection after a simple, inexpensive, and efficient preconcentration and clean-up hollow fiber-based LPME. Under optimized micro-extraction conditions, MEB enantiomers were extracted with 25 μl of 1-octanol within a lumen of a hollow fiber from 0.5 ml of plasma previously diluted with 4.5 ml alkalized water (pH 10). The chromatographic analysis was carried out through chiral liquid chromatography using a DELTA S column and hexane-isopropyl alcohol (85:15 v/v) containing 0.2% triethylamine as mobile phase. The mean recoveries of (+)-MEB and (-)-MEB were 75.5% and 71.0%, respectively. The limit of detection (LOD) was 3.0 ng/ml with linear response over the concentration range of 10-2500 ng/ml with correlation coefficient higher than 0.993 for both enantiomers. The pharmacokinetic studies showed that the mean plasma levels of (+)-MEB were higher than those of (-)-MEB at almost all time points. Also, (+)-MEB exhibited greater t(max) (peak time in concentration-time profile), C(max) (peak concentration in concentration-time profile), t(1/2) (elimination half-life), and AUC(0-240 min) (area under the curve for concentration versus time) and smaller CL (clearance) and V(d) (apparent distribution volume) than its antipode. The obtained results implied that the absorption, distribution, and elimination of (-)-MEB were more rapid than those of (+)-MEB and there were stereoselective differences in pharmacokinetics.     

The potential therapeutic use of renin–angiotensin system inhibitors in the treatment of inflammatory diseases

Inflammation is a normal part of the immune response to injury or infection but its dysregulation promotes the development of inflammatory diseases, which cause considerable human suffering. Nonsteroidal anti-inflammatory agents are the most commonly prescribed agents for the treatment of inflammatory diseases, but they are accompanied by a broad range of side effects, including gastrointestinal and cardiovascular events. The renin–angiotensin system (RAS) is traditionally known for its role in blood pressure regulation. However, there is increasing evidence that RAS signaling is also involved in the inflammatory response associated with several disease states. Angiotensin II increases blood pressure by binding to angiotensin type 1 (AT₁) receptor, and direct renin inhibitors, angiotensin-converting enzyme (ACE) inhibitors and AT₁ receptor blockers (ARBs) are clinically used as antihypertensive agents. Recent data suggest that these drugs also have anti-inflammatory effects. Therefore, this review summarizes these recent findings for the efficacy of two of the most widely used antihypertensive drug classes, ACE inhibitors and ARBs, to reduce or treat inflammatory diseases such as atherosclerosis, arthritis, steatohepatitis, colitis, pancreatitis, and nephritis.