27 research outputs found
Molecular diagnosis of Theileria and Babesia species infecting cattle in Northern Spain using reverse line blot macroarrays
BACKGROUND: Piroplasmosis in cattle is caused by tick-borne haemoprotozoan parasites of the genera Theileria and Babesia. Molecular detection techniques offer higher sensitivity and specificity than microscopy examination methods and serological tests. A reverse line blot (RLB) macroarray that included generic and species-specific probes for Theileria annulata, Theileria buffeli, Babesia bovis, Babesia bigemina, Babesia divergens and Babesia major was used to study the presence and identity of the piroplasm species infecting 263 bovine blood samples from 79 farms, most of them in Northern Spain. Microscopy examination of blood smears and haematology were also performed whenever possible to identify animals with parasitaemia. RESULTS: RLB hybridisation identified infection in 54.0% of the samples, whereas only 28.8% were positive by microscopy examination. The most frequently found species was T. buffeli, present in 42.6% of the samples. T. annulata was found in 22 samples (8.4%) from 12 farms, including 9 farms (14 samples) located in Northern Spain where presence of the vector is not very common. Babesia infections were less frequently detected: B. major was found in 3.0% of the samples, B. bigemina in 2.7%, B. bovis in 2.3% and B. divergens in 1.1%. Mixed infections were detected in 14 samples, accounting for six different combinations of species. CONCLUSION: This is the first report in which B. major and B. divergens have been detected in Spain using molecular identification techniques and the first time that B. bovis has been detected in Northern Spain. The detection of T. annulata in Northern Spain suggests that the distribution of Mediterranean theileriosis might be changing. Samples with positive RLB hybridisation but negative microscopy had haematology values within the normal ranges suggesting that they corresponded to chronic carriers that may serve as reservoirs of the infection. In this sense, sensitive and specific laboratorial tests like RLB that clearly identify the parasite and can detect subclinical infections are essential to establish good control measures
Bioorthogonal Self-Immolative Linker Based on Grob Fragmentation.
A self-immolative bioorthogonal conditionally cleavable linker based on Grob fragmentation is described. It is derived from 1,3-aminocyclohexanols and allows the release of sulfonate-containing compounds in aqueous media. Modulation of the amine pKa promotes fragmentation even at slightly acidic pH, a common feature of several tumor environments. The Grob fragmentation can also occur under physiological conditions in living cells, highlighting the potential bioorthogonal applicability of this reaction
In vivo biocompatibility testing of nanoparticle-functionalized alginateâchitosan scaffolds for tissue engineering applications
Background: There is a strong interest in designing new scaffolds for their potential application in tissue engineering and regenerative medicine. The incorporation of functionalization molecules can lead to the enhancement of scaffold properties, resulting in variations in scaffold compatibility. Therefore, the efficacy of the therapy could be compromised by the foreign body reaction triggered after implantation.Methods: In this study, the biocompatibilities of three scaffolds made from an alginateâchitosan combination and functionalized with gold nanoparticles (AuNp) and alginate-coated gold nanoparticles (AuNp + Alg) were evaluated in a subcutaneous implantation model in Wistar rats. Scaffolds and surrounding tissue were collected at 4-, 7- and 25-day postimplantation and processed for histological analysis and quantification of the expression of genes involved in angiogenesis, macrophage profile, and proinflammatory (IL-1ÎČ and TNFα) and anti-inflammatory (IL-4 and IL-10) cytokines.Results: Histological analysis showed a characteristic foreign body response that resolved 25 days postimplantation. The intensity of the reaction assessed through capsule thickness was similar among groups. Functionalizing the device with AuNp and AuNp + Alg decreased the expression of markers associated with cell death by apoptosis and polymorphonuclear leukocyte recruitment, suggesting increased compatibility with the host tissue. Similarly, the formation of many foreign body giant cells was prevented. Finally, an increased detection of alpha smooth muscle actin was observed, showing the angiogenic properties of the elaborated scaffolds.Conclusion: Our results show that the proposed scaffolds have improved biocompatibility and exhibit promising potential as biomaterials for elaborating tissue engineering constructs
Bioorthogonal Self-Immolative Linker Based on Grob Fragmentation
A self-immolative bioorthogonal conditionally
cleavable linker based on Grob fragmentation is described. It is
derived from 1,3-aminocyclohexanols and allows the release of
sulfonate-containing compounds in aqueous media. Modulation of
the amine pKa promotes fragmentation even at slightly acidic pH, a
common feature of several tumor environments. The Grob
fragmentation can also occur under physiological conditions in
living cells, highlighting the potential bioorthogonal applicability of
this reaction.We thank the Agencia Estatal de InvestigaciĂłn of Spain (AEI;
Grant No. RTI2018-099592âB-C21). This project has
received funding from the European Unionâs Horizon 2020
research and innovation programme under the Marie
SkĆodowska-Curie Grant Agreement No. 675007. M.S.-C.
thanks the AsociaciĂłn EspanÌola Contra el CĂĄncer AECC (La
Rioja) for the predoctoral fellowship. E.J.-M. acknowledges the
contract Beatriz Galindo from the Ministry of Universities of
Spain.Peer reviewe
Structure-Guided Approach for the Development of MUC1-Glycopeptide-Based Cancer Vaccines with Predictable Responses
Mucin-1 (MUC1) glycopeptides are exceptional candidates for potential cancer vaccines. However, their autoantigenic nature often results in a weak immune response. To overcome this drawback, we carefully engineered synthetic antigens with precise chemical modifications. To be effective and stimulate an anti-MUC1 response, artificial antigens must mimic the conformational dynamics of natural antigens in solution and have an equivalent or higher binding affinity to anti-MUC1 antibodies than their natural counterparts. As a proof of concept, we have developed a glycopeptide that contains noncanonical amino acid (2S,3R)-3-hydroxynorvaline. The unnatural antigen fulfills these two properties and effectively mimics the threonine-derived antigen. On the one hand, conformational analysis in water shows that this surrogate explores a landscape similar to that of the natural variant. On the other hand, the presence of an additional methylene group in the side chain of this analog compared to the threonine residue enhances a CH/Ï interaction in the antigen/antibody complex. Despite an enthalpyâentropy balance, this synthetic glycopeptide has a binding affinity slightly higher than that of its natural counterpart. When conjugated with gold nanoparticles, the vaccine candidate stimulates the formation of specific anti-MUC1 IgG antibodies in mice and shows efficacy comparable to that of the natural derivative. The antibodies also exhibit cross-reactivity to selectively target, for example, human breast cancer cells. This investigation relied on numerous analytical (e.g., NMR spectroscopy and X-ray crystallography) and biophysical techniques and molecular dynamics simulations to characterize the antigenâantibody interactions. This workflow streamlines the synthetic process, saves time, and reduces the need for extensive, animal-intensive immunization procedures. These advances underscore the promise of structure-based rational design in the advance of cancer vaccine development
Structure-Guided Approach for the Development of MUC1-Glycopeptide-Based Cancer Vaccines with Predictable Responses
Mucin-1(MUC1)glycopeptidesareexceptionalcandidatesforpotentialcancervaccines.However,theirautoantigenicnatureoftenresultsinaweakimmuneresponse.Toovercomethisdrawback,wecarefullyengineeredsyntheticantigenswithprecisechemicalmodifications.Tobeeffectiveandstimulateananti-MUC1response,artificialantigensmustmimictheconforma-tionaldynamicsofnaturalantigensinsolutionandhaveanequivalentorhigherbindingaffinitytoanti-MUC1antibodiesthantheirnaturalcounterparts.Asa proofofconcept,wehavedevelopeda glycopeptidethatcontainsnoncanonicalaminoacid(2S,3R)-3-hydroxynorvaline.Theunnaturalantigenfulfillsthesetwopropertiesandeffectivelymimicsthethreonine-derivedantigen.Ontheonehand,conformationalanalysisinwatershowsthatthissurrogateexploresalandscapesimilartothatofthenaturalvariant.Ontheotherhand,thepresenceofanadditionalmethylenegroupinthesidechainofthisanalogcomparedtothethreonineresidueenhancesa CH/interactionintheantigen/antibodycomplex.Despiteanenthalpyentropybalance,thissyntheticglycopeptidehasabindingaffinityslightlyhigherthanthatofitsnaturalcounterpart.Whenconjugatedwithgoldnanoparticles,thevaccinecandidatestimulatestheformationofspecificanti-MUC1IgGantibodiesinmiceandshowsefficacycomparabletothatofthenaturalderivative.Theantibodiesalsoexhibitcross-reactivitytoselectivelytarget,forexample,humanbreastcancercells.Thisinvestigationreliedonnumerousanalytical(e.g.,NMRspectroscopyandX-raycrystallography)andbiophysicaltechniquesandmoleculardynamicssimulationstocharacterizetheantigenantibodyinteractions.Thisworkflowstreamlinesthesyntheticprocess,savestime,andreducestheneedforextensive,animal-intensiveimmunizationprocedures.Theseadvancesunderscorethepromiseofstructure-basedrationaldesignintheadvanceofcance
Adrenomedullin and tumour microenvironment
Adrenomedullin (AM) is a regulatory peptide whose involvement in tumour progression is becoming more relevant with recent studies. AM is produced and secreted by the tumour cells but also by numerous stromal cells including macrophages, mast cells, endothelial cells, and vascular smooth muscle cells. Most cancer patients present high levels of circulating AM and in some cases these higher levels correlate with a worst prognosis. In some cases it has been shown that the high AM levels return to normal following surgical removal of the tumour, thus indicating the tumour as the source of this excessive production of AM. Expression of this peptide is a good investment for the tumour cell since AM acts as an autocrine/paracrine growth factor, prevents apoptosis-mediated cell death, increases tumour cell motility and metastasis, induces angiogenesis, and blocks immunosurveillance by inhibiting the immune system. In addition, AM expression gets rapidly activated by hypoxia through a HIF-1α mediated mechanism, thus characterizing AM as a major survival factor for tumour cells. Accordingly, a number of studies have shown that inhibition of this peptide or its receptors results in a significant reduction in tumour progression. In conclusion, AM is a great target for drug development and new drugs interfering with this system are being developed
Agaricus Mushroom-Enriched Diets Modulate the Microbiota-Gut-Brain Axis and Reduce Brain Oxidative Stress in Mice
Neurodegenerative diseases pose a major problem for developed countries, and stress has been identified as one of the main risk factors in the development of these disorders. Here, we have examined the protective properties against brain oxidative stress of two diets supplemented with 5% (w/w) of Agaricus bisporus (white button mushroom) or Agaricus bisporus brunnescens (Portobello mushroom) in mice. These diets did not modify the weight gain of the animals when compared to those fed with a regular diet, even after feeding on them for 15 weeks. The long-term modification of the microbiota after 12 weeks on the diets was investigated. At the phylum level, there was a large increase of Verrucomicrobia and a reduction of Cyanobacteria associated with the mushroom diets. No changes were observed in the Firmicutes/Bacteroidetes ratio, whose stability is a marker for a healthy diet. At the family level, three groups presented significant variations. These included Akkermansiaceae and Tannerellaceae, which significantly increased with both diets; and Prevotellaceae, which significantly decreased with both diets. These bacteria participate in the generation of microbiota-derived short-chain fatty acids (SCFAs) and provide a link between the microbiota and the brain. Mice subjected to restraint stress showed an upregulation of Il-6, Nox-2, and Hmox-1 expression; a reduction in the enzymatic activities of catalase and superoxide dismutase; and an increase in lipid peroxidation in their brains. All these parameters were significantly prevented by feeding for 3 weeks on the Agaricus-supplemented diets. In summary, the supplementation of a healthy diet with Agaricus mushrooms may significantly contribute to prevent neurodegenerative diseases in the general population
Adrenomedullin regulates club cell recovery following lung epithelial injury
The equilibrium between lung epithelium
damage and recovery in the context of chronic injury is
at the basis of numerous lung diseases, including lung
cancer and COPD. Understanding the contribution of
growth factors and other molecular intermediates to this
crosstalk may help in devising new therapeutic
approaches. To better understand the contribution of
adrenomedullin (AM) to lung homeostasis, we built club
cell-specific conditional knockout (KO) mice for AM
and subjected them to naphthalene injury. Untreated KO
mice had lower levels of club cell 10 KDa protein
(CC10) immunoreactivity than their wild type (WT)
littermates in both terminal and regular bronchioles.
Naphthalene injury resulted in a rapid necrosis of club
cells followed by a progressive recovery of the
epithelium. Club cells proliferated at higher rates in the
KO mice and at 21 days post-injury the club cell
coverage of the main bronchioles was higher and more
homogeneous than in the WT animals. In conclusion, the
paracrine/autocrine influence of AM in club cells subtly
modulates their proliferation and spreading kinetics
during lung epithelium recovery