HLA-G Is Widely Expressed by Mast Cells in Regions of Organ Fibrosis in the Liver, Lung and Kidney

We previously demonstrated that mast cells expressing HLA-G are associated with regions of hepatitis C virus-induced liver fibrosis. Here, we aimed to determine whether HLA-G expression in mast cells is specific to viral etiology, the liver, or to the general process of fibrosis. We enumerated HLA-G+ cells and mast cells by the immunohistochemistry of (i) liver blocks from 41 cases of alcoholic cirrhosis, (ii) 10 of idiopathic pulmonary fibrosis (IPF), and (iii) 10 of renal fibrosis. The nature of the HLA-G+ cells was specified by multiplex immunofluorescence using software. More than half of all HLA-G+ cells were mast cells in fibrotic areas of alcoholic cirrhosis and IPF. In the kidneys, subjected to fibrosis, the HLA-G+ cells were indeed mast cells but could not be counted. Moreover, in certain cases of the liver and lung, we observed a number of cellular nodes, which were secondary or tertiary follicles, in which HLA-G was highly expressed by B lymphocytes. In conclusion, HLA-G+ mast cells could be observed in the fibrotic regions of all organs studied. Previous studies suggest a protective role for HLA-G+ mast cells against inflammation and fibrosis. The observed follicles with B lymphocytes that express HLA-G may also reinforce their antifibrotic role.

Histologic features in an autoimmune gastritis patient with hypergastrinemia: Call for a grading system for G cell hyperplasia

Introduction/Objective Autoimmune gastritis (AG) is characterized by oxyntic glands destruction, metaplasia, enterochromaffin-like endocrine cell abnormality and G-cell hyperplasia with hypergastrinemia. The gastrin level can be extraordinarily high in certain cases to justify suspicion of Zollinger-Ellison syndrome. We herein report one such case and discuss clinical implication of a grading system for G-cell hyperplasia to correlate histology with gastrin levels. Methods/Case Report The patient was a symptomatic 65 year-old female with hypergastrinemia (2,068 pg/mL), negative abdomen/pelvis CT scan, positive anti-intrinsic factor and anti-parietal cell antibodies. Under esophagogastroduodenoscopy, biopsies were obtained from gastric cardia, fundus, corpus, incisura angularis, and antrum. Morphology and immunostains confirmed autoimmune gastritis. Diffuse linear pattern G-cell hyperplasia was evident in antrum and incisura angularis, counting up to 200 G-cells per linear millimeter. One study defined G-cell hyperplasia as >140 gastrin-positive cells per linear millimeter while another proposed a 2-tier stratification, i.e., simple hyperplasia (4-5 cells for each gland) and linear hyperplasia (continuous chain-like distribution of G-cells). Such scoring, however, was largely qualitative and fell short in delineating the extent of G-cell hyperplasia and correlation with gastrinemia. Results (if a Case Study enter NA) NA Conclusion Lack of G-cell grading system hindered our unequivocal determination of the G-cell hyperplasia as underlying or contributing cause of hypergastrenemia. The unique features of our case highlighted the necessity for installing a practical grading system that incorporates G-cell density, pattern (linear vs. nodular), extent of involved areas, other features of AG to correspond to gastrin level. With accumulation of clinical information, one such grading system is feasible and will improve our knowledge and patient care.

L-Arginine Reduces Nitro-Oxidative Stress in Cultured Cells with Mitochondrial Deficiency

L-Arginine (L-ARG) supplementation has been suggested as a therapeutic option in several diseases, including Mitochondrial Encephalomyopathy, Lactic Acidosis, and Stroke-like syndrome (MELAS), arguably the most common mitochondrial disease. It is suggested that L-ARG, a nitric oxide (NO) precursor, can restore NO levels in blood vessels, improving cerebral blood flow. However, NO also participates in mitochondrial processes, such as mitochondrial biogenesis, the regulation of the respiratory chain, and oxidative stress. This study investigated the effects of L-ARG on mitochondrial function, nitric oxide synthesis, and nitro-oxidative stress in cell lines harboring the MELAS mitochondrial DNA (mtDNA) mutation (m.3243A>G). We evaluated mitochondrial enzyme activity, mitochondrial mass, NO concentration, and nitro-oxidative stress. Our results showed that m.3243A>G cells had increased NO levels and protein nitration at basal conditions. Treatment with L-ARG did not affect the mitochondrial function and mass but reduced the intracellular NO concentration and nitrated proteins in m.3243A>G cells. The same treatment led to opposite effects in control cells. In conclusion, we showed that the main effect of L-ARG was on protein nitration. Lowering protein nitration is probably involved in the mechanism related to L-ARG supplementation benefits in MELAS patients.

A remixed-fermentation technique for the simultaneous bioconversion of corncob C6 and C5 sugars to probiotic Bacillus subtilis

The probiotic strain of Bacillus subtilis presents a promising application potential for the value-added bio-utilization of lignocellulosic carbohydrates. By the combined acidolysis pretreatment and enzymatic hydrolysis, hemicellulose and cellulose constituents of corncob were efficiently converted respectively into fermentable C5 and C6 sugars, mainly including xylose and glucose. B. subtilis grew well in xylose solution while it was hindered completely in the acidolysis broth because of the bio-toxicity of degraded chemicals derived from corncob. A mixed-fermentation technique was therefore developed and performed to blend the acidolysis broth and enzymatic hydrolysis slurry together, by which C5 and C6 sugar molecules were successfully fermented and efficiently utilized for the growth of B. subtilis cells with a yield of 0.33 g cells/g sugar consumed. A net amount of 186.1 ± 0.9 g of B. subtilis powder was obtained from 1000 g of corncob that could improve the economic benefits of the process to around 5–7 times.

Isolation of HLA-G+ cells using MEM-G/9 antibody-conjugated magnetic nanoparticles for prenatal screening: a reliable, fast and efficient method

Selective isolation of HLA-G+ cells from HLA-G− cells with MEM-G/9-MNPs. It is an efficient tool for the isolation of fetal cells from the endocervical sample for prenatal screening.

Ultrasound-assisted l-cysteine whole-cell bioconversion by recombinant Escherichia coli with tryptophan synthase

l-Cysteine is widely used in food, medicine, and cosmetics. In this study, a recombinant Escherichia coli whole-cell system with tryptophan synthase was used to complete the biological transformation of l-serine to l-cysteine, and bioconversion of l-cysteine was investigated by tryptophan synthase. The biotransformation of l-cysteine was optimized by response surface methodology. The optimal conditions obtained are 0.13 mol·L−1 l-serine, 75 min, 130 W ultrasound operation, where the V max of tryptophan synthase is 25.27 ± 0.16 (mmol·h−1·(g-cells)−1). The V max of tryptophan synthase for the biosynthesis without ultrasound is 12.91 ± 0.34 (mmol·h−1·(g-cells)−1). Kinetic analysis of the recombinant Escherichia coli whole-cell system with tryptophan synthase also showed that under the ultrasound treatment, the K m values of l-cysteine biosynthesis increase from 1.342 ± 0.11 mM for the shaking biotransformation to 2.555 ± 0.13 mM for ultrasound operation. The yield of l-cysteine reached 91% after 75 min of treatment after 130 W ultrasound, which is 1.9-fold higher than no ultrasound.

Effect of pH on xylitol production by Candida species from a prairie cordgrass hydrolysate

Using hydrolysates of the North American prairie grass prairie cordgrass buffered at pH 4.5, 5.0, 5.5 or 6.0, xylitol production, xylitol yield, cell biomass production and productivity were investigated for three strains of yeast Candida. Of the three strains, the highest xylitol concentration of 20.19 g xylitol (g xylose consumed)−1 and yield of 0.89 g xylitol (g xylose consumed)−1 were produced by Candida mogi ATCC 18364 when grown for 120 h at 30° C on the pH 5.5-buffered hydrolysate-containing medium. The highest biomass level being 7.7 g cells (kg biomass)−1 was observed to be synthesized by Candida guilliermondii ATCC 201935 after 120 h of growth at 30° C on a pH 5.5-buffered hydrolysate-containing medium. The highest xylitol specific productivity of 0.73 g xylitol (g cells h)−1 was determined for C. guilliermondii ATCC 20216 after 120 h of growth at 30°C on a pH 5.0-buffered hydrolysate-containing medium. Xylitol production and yield by the three Candida strains was higher on prairie cordgrass than what was previously observed for the same strains after 120 h at 30° C when another North American prairie grass big bluestem served as the plant biomass hydrolysate indicating that prairie cordgrass may be a superior plant biomass substrate.

The Release Behavior, Biocompatibility and Physical Properties of Ald-loaded Strontium Doped Calcium Phosphate Cement

The effect of concurrent attendance of two inhibitors of bone degradation, namely Alendronate (Ald) sodium trihydrate and Strontium (Sr), on Calcium Phosphate Cement (CPC) characteristics was explored. To this aim, 5 wt% Strontium and 21 mM Alendronate sodium trihydrate were used in calcium phosphate cement and setting time, ion and drug release were analyzed. RAW264.7 and G cell were cultured on cement samples and Tartrate-Resistant Acid Phosphatase (TRAP), Alkaline phosphatase (ALP) activity and MTT assay were studied. The results of structural analysis indicated that 21 mM Ald did not let the cement set. Therefore, colloidal silica was added to the cement formula and successfully decreased the setting time. In vitro tests showed Sr-loaded sample had a greater inhibitory effect on biocompatibility of G cells than Ald-loaded and Sr-Ald-loaded samples. In addition, the findings about osteoblast MTT and ALP activity indicated that Sr was more effective in osteogenic activity of G cells. The simultaneous presence of Ald and Sr in Calcium Phosphate Cement (CPC) was not as effective in its biocompatibility as the presence of Sr alone.

Stomach gastrin is regulated by sodium via PPAR-α and dopamine D1 receptor

Gastrin, secreted by stomach G cells in response to ingested sodium, stimulates the renal cholecystokinin B receptor (CCKBR) to increase renal sodium excretion. It is not known how dietary sodium, independent of food, can increase gastrin secretion in human G cells. However, fenofibrate (FFB), a peroxisome proliferator-activated receptor-α (PPAR-α) agonist, increases gastrin secretion in rodents and several human gastrin-secreting cells, via a gastrin transcriptional promoter. We tested the following hypotheses: (1.) the sodium sensor in G cells plays a critical role in the sodium-mediated increase in gastrin expression/secretion, and (2.) dopamine, via the D1R and PPAR-α, is involved. Intact human stomach antrum and G cells were compared with human gastrin-secreting gastric and ovarian adenocarcinoma cells. When extra- or intracellular sodium was increased in human antrum, human G cells, and adenocarcinoma cells, gastrin mRNA and protein expression/secretion were increased. In human G cells, the PPAR-α agonist FFB increased gastrin protein expression that was blocked by GW6471, a PPAR-α antagonist, and LE300, a D1-like receptor antagonist. LE300 prevented the ability of FFB to increase gastrin protein expression in human G cells via the D1R, because the D5R, the other D1-like receptor, is not expressed in human G cells. Human G cells also express tyrosine hydroxylase and DOPA decarboxylase, enzymes needed to synthesize dopamine. G cells in the stomach may be the sodium sensor that stimulates gastrin secretion, which enables the kidney to eliminate acutely an oral sodium load. Dopamine, via the D1R, by interacting with PPAR-α, is involved in this process.