24 research outputs found
In-vitro effect of heat stress on bovine monocytes lifespan and polarization
Heat stress (HS) has a negative impact on dairy cows’ health, milk production, reproductive performance and immune defenses. Cellular and molecular responses to high temperatures in bovine polymorphonuclear cells and peripheral blood mononuclear cells (PBMCs) have been investigated so far. On the contrary, the effects of high temperatures on isolated monocytes remain almost undisclosed. The aim of this study was to unravel the in vitro effects of high temperatures, simulating a severe HS related body hyperthermia, on bovine lifespan and M1/M2 polarisation. The PBMCs were isolated from whole blood of 9 healthy dairy cattle. Monocytes were sorted by magnetic activated cell sorting and cultured over night at 39 °C (normothermia) or 41 °C (HS). Apoptotic rate and viability were assessed and mRNA abundance for heat shock proteins (HSPs), heat transcription factors (HSFs) and genes involved in monocyte/macrophage polarization (STAT1, STAT2, STAT3, STAT6, IL1β, TGF1β, IL-10, COX2) were quantified by qPCR. We found that apoptosis increased in monocytes exposed to 41 °C, as compared to control, while viability conversely decreased. HS increased the abundance of HSF1 and HSP70. The concomitant decrease of STAT1 and STAT2 and the increase of STAT6 genes abundance at 41 °C suggest, at transcriptional factors level, a polarization of monocytes from a classical activated M1 to a non-classically activated M2 monocytes. In conclusion, the exposure of bovine monocytes to high temperatures affects their lifespan as well as the abundance of genes involved in HS response and in monocyte/macrophages polarization phenotype, confirming that bovine immune response may be significantly affected by hyperthermia
GZMKhigh CD8+ T effector memory cells are associated with CD15high neutrophil abundance in non-metastatic colorectal tumors and predict poor clinical outcome.
CD8(+) T cells are a major prognostic determinant in solid tumors, including colorectal cancer (CRC). However, understanding how the interplay between different immune cells impacts on clinical outcome is still in its infancy. Here, we describe that the interaction of tumor infiltrating neutrophils expressing high levels of CD15 with CD8(+) T effector memory cells (T(EM)) correlates with tumor progression. Mechanistically, stromal cell-derived factor-1 (CXCL12/SDF-1) promotes the retention of neutrophils within tumors, increasing the crosstalk with CD8(+) T cells. As a consequence of the contact-mediated interaction with neutrophils, CD8(+) T cells are skewed to produce high levels of GZMK, which in turn decreases E-cadherin on the intestinal epithelium and favors tumor progression. Overall, our results highlight the emergence of GZMK(high) CD8(+) T(EM) in non-metastatic CRC tumors as a hallmark driven by the interaction with neutrophils, which could implement current patient stratification and be targeted by novel therapeutics
Stereoselective synthesis of alpha and beta-L-C-fucosyl aldehydes and their utility in the assembly of C-fucosides of biological relevance
An efficient synthesis of O-benzylated derivatives of the title sugar aldehydes via thiazole addition to tri-O-benzyl-L-fuconolactone followed by highly stereoselective deoxygenation of the resulting thiazolylketose and thiazole to formyl transformation is described. Wittig olefination of these aldehydes with galactopyranose and glucopyranose 6-phosphoranes and reduction of the resulting alkenes afforded alpha- and beta-linked (1-6)-L-C-fucosyl disaccharides, namely, beta-L-C-Fuc-(1-6)-alpha-DGal, alpha-L-C-Fuc-(1-6)-alpha-D-Gal, and alpha-L-C-Fuc-(1-6)-alpha-D-Glc. The alpha-anomer of the above C-fucosyl aldehydes was transformed into a C-fucosylmethyl triphenylphosphonium iodide from which the corresponding C-fucosylmethylene phosphorane was generated upon treatment with BuLi. This phosphorane reacted with the Garner aldehyde (N-Boc D-serinal acetonide) and its one-carbon higher homologue to give alkenes whose reduction and unveiling of the glycinyl group from the oxazolidine ring afforded C-fucosyl alpha-amino acids, namely alpha-L-linked C-fucosyl serines and C-fucosyl asparagines.
As a final test of the synthetic utility of the title aldehydes, the beta-anomer was employed as starting material in the stereoselective synthesis of both R- and S-epimer L-C-fucosyl phenylhydroxy acetates. One epimer was obtained by reaction of the sugar aldehyde with phenylmagnesium bromide, oxidation of the resulting alcohol to ketone, addition of 2-lithiothiazole to the latter, and transformation of the thiazole ring into the carboxyl group through an aldehyde intermediate. The other epimer was obtained by the same procedure and inverting the timing of phenyl and thiazolyl group addition. In both routes, the key step establishing the configuration of the quaternary carbon atom of the aliphatic chain was the highly stereoselective addition of the organometal to the ketone intermediate
Concise and practical synthesis of C-glycosyl ketones from sugar benzothiazoles and their transformation into chiral tertiary alcohols
A collection of 13 unsymmetrical ketones, each one featuring a sugar (D-glucosyl, D-galactosyl, D-mannosyl, and L-fucosyl) and an aglycone moiety (phenyl, 2-thiazolyl, TMS-ethynyl, allyl, and 1-propenyl) was prepared by a uniform route based on the use of benzothiazole as a carbonyl group equivalent. Succinctly, C-glycosylbenzothiazoles readily prepared by addition of 2-lithiobenzothiazole to sugar lactones and deoxygenation, were subjected to a one-pot reaction sequence involving N-methylation of the heterocyclic ring by MeOTf, treatment of the N-methylbenzothiazolium salt with a Grignard reagent, and HgCl2-promoted hydrolysis of the benzothiazoline thus formed. The resulting ketones were isolated in yields varying from 35 to 80%. Treatment of the sugar ketones
with various organometals containing the phenyl, 2-thiazolyl, TMS-ethynyl, or ethynyl group as a substituent afforded chiral tertiary alcohols. These addition reactions were highly stereoselective as observed by crude NMR analysis and isolation of a single epimer in high yield in each case examined. However, because of the complexity of the reagents involved, the stereochemical outcome of these reactions appears to be difficult to rationalize by simple classical steric models, thus, ab
initio studies taking into account the role of the sugar fragment are advisable. An interesting synthetic elaboration of a propargylic alcohol containing the thiazole ring into a propargylic alcohol bearing the formyl and carboxylate groups is reported
In-vitro effect of heat stress on bovine monocytes lifespan and polarization
Heat stress (HS) has a negative impact on dairy cows' health, milk production, reproductive performance and immune defenses. Cellular and molecular responses to high temperatures in bovine polymorphonuclear cells and peripheral blood mononuclear cells (PBMCs) have been investigated so far. On the contrary, the effects of high temperatures on isolated monocytes remain almost undisclosed. The aim of this study was to unravel the in vitro effects of high temperatures, simulating a severe HS related body hyperthermia, on bovine lifespan and M1/M2 polarisation. The PBMCs were isolated from whole blood of 9 healthy dairy cattle. Monocytes were sorted by magnetic activated cell sorting and cultured over night at 39 \ub0C (normothermia) or 41 \ub0C (HS). Apoptotic rate and viability were assessed and mRNA abundance for heat shock proteins (HSPs), heat transcription factors (HSFs) and genes involved in monocyte/macrophage polarization (STAT1, STAT2, STAT3, STAT6, IL1\u3b2, TGF1\u3b2, IL-10, COX2) were quantified by qPCR. We found that apoptosis increased in monocytes exposed to 41 \ub0C, as compared to control, while viability conversely decreased. HS increased the abundance of HSF1 and HSP70. The concomitant decrease of STAT1 and STAT2 and the increase of STAT6 genes abundance at 41 \ub0C suggest, at transcriptional factors level, a polarization of monocytes from a classical activated M1 to a non-classically activated M2 monocytes. In conclusion, the exposure of bovine monocytes to high temperatures affects their lifespan as well as the abundance of genes involved in HS response and in monocyte/macrophages polarization phenotype, confirming that bovine immune response may be significantly affected by hyperthermia
Role of the microbiome in the development and treatment of gastric cancer: an overview of the biological and clinical landscape
For decades, the stomach was considered a sterile organ, due to the acid environment. However, starting from the discovery of Helicobacter pylori, this concept has progressively refined. By damaging the hydrochloric acid-secreting glands, H. pylori infection primes the progression from acute to chronic inflammation in gastric mucosa resulting in atrophic gastritis, intestinal metaplasia, dysplasia and ultimately gastric cancer (GC). Due to the challenging identification of culturing bacteria, the carcinogenic role of gastric microbial community, other than H. pylori, remains underestimated. More recently, a growing body of evidence has pointed out the dynamism of gastric microbiota as a crucial step for GC development, besides elucidating some additional activity in modulating the efficacy of cancer treatments. In turn, anticancer therapies can shape gastric microbiota with consequent dysbiosis and a potential correlation with drug-related toxicity. In conclusion, the current review aims to deepen the role of gut microbiota as a key factor in gastric disease at multiple levels, from carcinogenesis to the metastatic phase. It also provides novel insights on gastric microbiota as potential target for tailoring multimodal strategies, either surgical or oncological, to finally provide our patients with more individualized treatment options
Radioligand binding assay versus immunoenzimatic tecnique for steroid receptor determination in mammary cancer
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Transcriptomic analysis of the developing rabbit's lung: implication of premature birth and post-natal oxygen exposure
Preterm birth alters normal lung development, leading to bronchopulmonary dysplasia (BPD). Preterm rabbit is being recognized as a relevant BPD model, but a deeper molecular characterization is needed.
The aim was to characterize premature birth and postnatal oxygen impact on lung molecular pathways. Preterm pups delivered at 28 days of gestation were randomly assigned to hyperoxia (HOX 70% O2, n=12) or room-air (RA, 21% O2, n=27) for 14 days. Lungs were harvested at postnatal days 1, 3, 5, 7, 9, 11, and 14. Age-matched term pups were used as controls (n=27). Radial alveolar count (RAC), acute lung injury (ALI) and transcriptomic analyses were performed.
Term pups showed significantly better RAC and ALI scores compared to preterm groups (P< 0.05 Term vs RA; and P<0.001 Term vs HOX), while the HOX group showed significantly worse RAC and ALI scores than preterm RA and term animals (P<0.001). The amount of differentially expressed genes between term and preterm pups increases with increasing distance from birth. On day 14, 1056 genes appear dysregulated due to premature birth. Pathway enrichment analysis showed that premature birth alone triggers the upregulation of pro-inflammatory and immune activation pathways and downregulates lung and vasculature development pathways. These pathways are exacerbated by postnatal oxygen exposure.
Premature birth by itself leads to a lung and vasculature developmental gap compared to age-matched term controls, which can be enhanced by postnatal HOX exposure, highlighting the translational value of preterm rabbits for studying the dysregulation of lung development-related pathways common to human BPD
GZMKhigh CD8+ T effector memory cells are associated with CD15high neutrophil abundance in non-metastatic colorectal tumors and predict poor clinical outcome
CD8+ T cells are a major prognostic determinant in solid tumors, including colorectal cancer (CRC). However, understanding how the interplay between different immune cells impacts on clinical outcome is still in its infancy. Here, we describe that the interaction of tumor infiltrating neutrophils expressing high levels of CD15 with CD8+ T effector memory cells (TEM) correlates with tumor progression. Mechanistically, stromal cell-derived factor-1 (CXCL12/SDF-1) promotes the retention of neutrophils within tumors, increasing the crosstalk with CD8+ T cells. As a consequence of the contact-mediated interaction with neutrophils, CD8+ T cells are skewed to produce high levels of GZMK, which in turn decreases E-cadherin on the intestinal epithelium and favors tumor progression. Overall, our results highlight the emergence of GZMKhigh CD8+ TEM in non-metastatic CRC tumors as a hallmark driven by the interaction with neutrophils, which could implement current patient stratification and be targeted by novel therapeutics
