144 research outputs found
Interleukin-13 induces expression and release of interleukin-1 decoy receptor in human polymorphonuclear cells.
The aim of this study was to examine whether interleukin-13 (IL-13), a cytokine with anti-inflammatory activities, affected expression of interleukin-1 (IL-1) receptors (R) in human polymorphonuclear cells (PMN). Treatment with IL-13 augmented both type I and type II (decoy) R transcripts, with the latter being by far the most represented. The transcriptional inhibitor actinomycin D blocked the induction of IL-1 R mRNAs by IL-13. Nuclear run-off experiments demonstrated an augmented transcriptional rate of IL-1 decoy R in IL-13-treated B lymphoblastoid cells. The protein synthesis inhibitor cycloheximide blocked type I R expression but superinduced decoy R expression. IL-13 augmented the binding of radiolabeled IL-1 beta on the PMN surface with an increased number of IL-1 receptors and no change in Kd values. IL-13 induced the surface expression of IL-1 decoy R and the release by PMN of an IL-1-binding protein identified as a soluble version of the IL-1 decoy R. These results show that PMN is an important target for IL-13 and that induction of expression and release of the IL-1 decoy R, in concert with inhibition of cytokine synthesis, may represent an important mechanism by which IL-13 blocks IL-1, a central mediator of inflammatory reactions
B Cell Anergy Modulated by TLR1/2 and the miR-17∼92 Cluster Underlies the Indolent Clinical Course of Chronic Lymphocytic Leukemia Stereotyped Subset #4
Abstract
Chronic lymphocytic leukemia (CLL) patients assigned to stereotyped subset #4 (mutated IGHV4-34/IGKV2-30 BCR Ig) display a particularly indolent disease course. Immunogenetic studies of the clonotypic BCR Ig of CLL subset #4 suggested a resemblance with B cells rendered anergic through chronic autoantigenic stimulation. In this article, we provide experimental evidence that subset #4 CLL cells show low IgG levels, constitutive ERK1/2 activation, and fail to either release intracellular Ca2+ or activate MAPK signaling after BCR cross-linking, thus displaying a signature of B cell anergy at both biochemical and functional levels. Interestingly, TLR1/2 triggering restored BCR functionality, likely breaching the anergic state, and this was accompanied by induction of the miR-17∼92 cluster, whose members target critical BCR-associated molecules, including MAPKs. In conclusion, we demonstrate BCR anergy in CLL subset #4 and implicate TLR signaling and the miR-17∼92 cluster in the regulation of the anergic state. This detailed signaling profiling of subset #4 has implications for advanced understanding of the complex regulation of intracellular signaling pathways in CLL, currently a major therapeutic target of the disease
Nanoscale mapping of the conductivity and interfacial capacitance of an electrolyte-gated organic field-effect transistor under operation
Versió postprint del document publicat a: https://doi.org/10.1002/adfm.202008032Probing nanoscale electrical properties of organic semiconducting materials at the interface with an electrolyte solution under externally applied voltages is key in the field of organic bioelectronics. It is demonstrated that the conductivity and interfacial capacitance of the active channel of an electrolyte-gated organic field‐effect transistor (EGOFET) under operation can be probed at the nanoscale using scanning dielectric microscopy in force detection mode in liquid environment. Local electrostatic force versus gate voltage transfer characteristics are obtained on the device and correlated with the global current–voltage transfer characteristics of the EGOFET. Nanoscale maps of the conductivity of the semiconducting channel show the dependence of the channel conductivity on the gate voltage and its variation along the channel due to the space charge limited conduction. The maps reveal very small electrical heterogeneities, which correspond to local interfacial capacitance variations due to an ultrathin non-uniform insulating layer resulting from a phase separation in the organic semiconducting blend. Present results offer insights into the transduction mechanism at the organic semiconductor/electrolyte interfaces at scales down to ≈100 nm, which can bring substantial optimization of organic electronic devices for bioelectronic applications such as electrical recording on excitable cells or label-free biosensing
Innovative superparamagnetic iron-oxide nanoparticles coated with silica and conjugated with linoleic acid: Effect on tumor cell growth and viability
One of the goals for the development of more effective cancer therapies with reduced toxic side effects is the optimization of innovative treatments to selectively kill tumor cells. The use of nanovectors loaded with targeted therapeutic payloads is one of the most investigated strategies. In this paper superparamagnetic iron oxide nanoparticles (SPIONs) coated by a silica shell or uncoated, were functionalized with single-layer and bi-layer conjugated linoleic acid (CLA). Silica was used to protect the magnetic core from oxidation, improve the stability of SPIONs and tailor their surface reactivity. CLA was used as novel grafting biomolecule for its anti-tumor activity and to improve particle dispersibility. Mouse breast cancer 4T1 cells were treated with these different SPIONs. SPIONs functionalized with the highest quantity of CLA and coated with silica shell were the most dispersed. Cell viability was reduced by SPIONs functionalized with CLA in comparison with cells which were untreated or treated with SPIONs without CLA. As regards the types of SPIONs functionalized with CLA, the lowest viability was observed in cells treated with uncoated SPIONs with the highest quantity of CLA. In conclusion, the silica shell free SPIONs functionalized with the highest amount of CLA can be suggested as therapeutic carriers because they have the best dispersion and ability to decrease 4T1 cell viability
Clinical expression of facioscapulohumeral muscular dystrophy in carriers of 1-3 D4Z4 reduced alleles: Experience of the FSHD Italian National Registry
OBJECTIVES:
Facioscapulohumeral muscular dystrophy type 1 (FSHD1) has been genetically linked to reduced numbers ( 64 8) of D4Z4 repeats at 4q35. Particularly severe FSHD cases, characterised by an infantile onset and presence of additional extra-muscular features, have been associated with the shortest D4Z4 reduced alleles with 1-3 repeats (1-3 DRA). We searched for signs of perinatal onset and evaluated disease outcome through the systematic collection of clinical and anamnestic records of de novo and familial index cases and their relatives, carrying 1-3 DRA.
SETTING:
Italy.
PARTICIPANTS:
66 index cases and 33 relatives carrying 1-3 DRA.
OUTCOMES:
The clinical examination was performed using the standardised FSHD evaluation form with validated inter-rater reliability. To investigate the earliest signs of disease, we designed the Infantile Anamnestic Questionnaire (IAQ). Comparison of age at onset was performed using the non-parametric Wilcoxon rank-sum or Kruskal-Wallis test. Comparison of the FSHD score was performed using a general linear model and Wald test. Kaplan-Meier survival analysis was used to estimate the age-specific cumulative motor impairment risk.
RESULTS:
No patients had perinatal onset. Among index cases, 36 (54.5%) showed the first signs by 10 years of age. The large majority of patients with early disease onset (26 out of 36, 72.2%) were de novo; whereas the majority of patients with disease onset after 10 years of age were familial (16, 53.3%). Comparison of the disease severity outcome between index cases with age at onset before and over 10 years of age, failed to detect statistical significance (Wald test p value=0.064). Of 61 index cases, only 17 (27.9%) presented extra-muscular conditions. Relatives carrying 1-3 DRA showed a large clinical variability ranging from healthy subjects, to patients with severe motor impairment.
CONCLUSIONS:
The size of the D4Z4 allele is not always predictive of severe clinical outcome. The high degree of clinical variability suggests that additional factors contribute to the phenotype complexity
Innovative superparamagnetic iron-oxide nanoparticles coated with silica and conjugated with linoleic acid: Effect on tumor cell growth and viability
One of the goals for the development of more effective cancer therapies with reduced toxic side effects is the optimization of innovative treatments to selectively kill tumor cells. The use of nanovectors loaded with targeted therapeutic payloads is one of the most investigated strategies. In this paper superparamagnetic iron oxide nanoparticles (SPIONs) coated by a silica shell or uncoated, were functionalized with single-layer and bi-layer conjugated linoleic acid (CLA). Silica was used to protect the magnetic core from oxidation, improve the stability of SPIONs and tailor their surface reactivity. CLA was used as novel grafting biomolecule for its anti-tumor activity and to improve particle dispersibility. Mouse breast cancer 4T1 cells were treated with these different SPIONs. SPIONs functionalized with the highest quantity of CLA and coated with silica shell were the most dispersed. Cell viability was reduced by SPIONs functionalized with CLA in comparison with cells which were untreated or treated with SPIONs without CLA. As regards the types of SPIONs functionalized with CLA, the lowest viability was observed in cells treated with uncoated SPIONs with the highest quantity of CLA. In conclusion, the silica shell free SPIONs functionalized with the highest amount of CLA can be suggested as therapeutic carriers because they have the best dispersion and ability to decrease 4T1 cell viability
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