Matzenshapiro7539
Hsp70 chaperone is one of the key protein machines responsible for the quality control of protein production in cells. Facilitating in vivo protein folding by counteracting misfolding and aggregation is the essence of its biological function. Although the allosteric cycle during its functional actions has been well characterized both experimentally and computationally, the mechanism by which Hsp70 assists protein folding is still not fully understood. In this work, we studied the Hsp70-mediated folding of model proteins with rugged energy landscape by using molecular simulations. Different from the canonical scenario of Hsp70 functioning, which assumes that folding of substrate proteins occurs spontaneously after releasing from chaperones, our results showed that the substrate protein remains in contacts with the chaperone during its folding process. The direct chaperone-substrate interactions in the open conformation of Hsp70 tend to shield the substrate sites prone to form non-native contacts, which therefore avoids the frustrated folding pathway, leading to a higher folding rate and less probability of misfolding. Our results suggest that in addition to the unfoldase and holdase functions widely addressed in previous studies, Hsp70 can facilitate the folding of its substrate proteins by remodeling the folding energy landscape and directing the folding processes, demonstrating the foldase scenario. These findings add new, to our knowledge, insights into the general molecular mechanisms of chaperone-mediated protein folding.
Neutrophil accumulation in the skin is a hallmark of psoriasis. Novel insights on neutrophil phenotypic and functional heterogeneity raise the question to what extent these cells contribute to the sustained inflammatory skin reaction.
We sought to examine the phenotype and functional properties of neutrophils in blood and skin of patients with psoriasis, and the effect of TNF-α and p40(IL-12/IL-23) antibody therapy on circulating neutrophils.
Thirty-two patients with psoriasis were enrolled in an observational study performed in 2 university hospitals. We evaluated neutrophil phenotype and function using invitro (co)culture stimulation assays, flow cytometry, multiplex immunohistochemistry, and multispectral imaging of patient-derived blood and skin samples.
Cluster of differentiation (CD)10
and CD10
neutrophils were increased in peripheral blood of patients with psoriasis. In CD10
neutrophils, different maturation stages were observed, including a subset resembling aged neutrophils that was 3 times more abundant than in healthy individuals. These aged neutrophils displayed suboptimal canonical neutrophil functions and induced IL-17 and IFN-γ production by T cells invitro, mediated by neutrophil extracellular trap formation. GDC-0941 research buy Also, mature and aged neutrophils were present in psoriatic skin and were found in the vicinity of T cells. Upon antibody therapy, numbers of these cells in circulation decreased.
Patients with psoriasis reveal a unique neutrophil profile in circulation, and 2 distinct neutrophil subsets are present in psoriatic skin. Targeted biological treatment may aid in the containment of sustained neutrophil-mediated inflammation.
Patients with psoriasis reveal a unique neutrophil profile in circulation, and 2 distinct neutrophil subsets are present in psoriatic skin. Targeted biological treatment may aid in the containment of sustained neutrophil-mediated inflammation.
Lipoprotein apheresis (LA) is an extracorporeal therapy which removes apolipoprotein B-containing particles from the circulation. We evaluated techniques and efficiency of lipoprotein apheresis procedures applied to patients with familial and non-familial hypercholesterolemia (FH) at our center.
We retrospectively evaluated 250 LA procedures applied to 27 patients with dyslipidemia between March 2011 and August 2019.
A total of 27 patients, of whom 19 (70.4%) were male and 8 (29.6%), female, were included. Eighteen (66.7%), 6 (22.2%) and 3 (11.1%) patients were diagnosed with non-FH, homozygous FH (HoFH) and heterozygous FH (HeFH), respectively. Two different apheresis techniques, direct adsorption of lipoproteins (DALI) (48.8%) and double filtration plasmapheresis (DFPP) (51.2%), were used. The change in the serum total cholesterol (TC) level was the median 302 mg/dl (171-604 mg/dl) (60.4%) in HoFH patients, 305 mg/dl (194-393 mg/dl) (60.8%) in HeFH patients and 227 mg/dl (75-749 mg/dl) (65.3%) in non-FH patients. The change in the serum low-density lipoprotein (LDL) level was the median 275 mg/dl (109-519 mg/dl) (64.2%), 232 mg/dl (207-291 mg/dl) (64.5%) and 325 mg/dl (22-735 mg/dl) (70.9%) in patients with HoFH, HeFH and non-FH, respectively. A significantly effective reduction in serum lipid levels, including TC, LDL and triglycerides, was achieved in all patients, regardless of the technique, p < .001. The decrease in the serum TC and LDL levels was significantly higher in the DFPP, compared to the DALI, being 220 mg/dl (-300 to 771) vs 184 mg/dl (64-415), p < .001 and 196 mg/dl (11-712) vs 157 mg/dl (54-340), p < .001, respectively.
Our results showed that LA is a highly effective treatment in reducing serum lipid levels and safe, without any major adverse event.
Our results showed that LA is a highly effective treatment in reducing serum lipid levels and safe, without any major adverse event.The American Initiative in Mast Cell Diseases (AIM) held its inaugural investigator conference at Stanford University School of Medicine in May 2019. The overarching goal of this meeting was to establish a Pan-American organization of physicians and scientists with multidisciplinary expertise in mast cell disease. To serve this unmet need, AIM envisions a network where basic, translational, and clinical researchers could establish collaborations with both academia and biopharma to support the development of new diagnostic methods, enhanced understanding of the biology of mast cells in human health and disease, and the testing of novel therapies. In these AIM proceedings, we highlight selected topics relevant to mast cell biology and provide updates regarding the recently described hereditary alpha-tryptasemia. In addition, we discuss the evaluation and treatment of mast cell activation (syndromes), allergy and anaphylaxis in mast cell disorders, and the clinical and biologic heterogeneity of the more indolent forms of mastocytosis.