Isolation method of brain microvessels from small frozen human brain tissue for blood-brain barrier protein expression analysis.

Background: Protein expression analysis of isolated brain microvessels provides valuable insights into the function of the blood-brain barrier (BBB). However, isolation of brain microvessels from human brain tissue, particularly in small quantities, poses significant challenges. This study presents a method for isolating brain microvessels from a small amount of frozen human brain tissue, adapting techniques from an established mouse brain capillary isolation method.

Increased CSN5 expression enhances the sensitivity to lenalidomide in multiple myeloma cells.

Lenalidomide (LEN) is commonly used as an effective therapeutic agent for multiple myeloma (MM). However, in some patients, primary resistance to LEN is observed, the mechanisms of which remain poorly understood. In this study, we combined a LEN sensitivity assay with proteomics data from 15 MM cell lines to identify protein expression profiles associated with primary LEN resistance.

Fibrillin-1 G234D mutation in the hybrid1 domain causes tight skin associated with dysregulated elastogenesis and increased collagen cross-linking in mice.

Fibrillin-1, an extracellular matrix (ECM) protein encoded by the FBN1 gene, serves as a microfibril scaffold crucial for elastic fiber formation and homeostasis in pliable tissue such as the skin. Aside from causing Marfan syndrome, some mutations in FBN1 result in scleroderma, marked by hardened and thicker skin which limits joint mobility. Here, we describe a tight skin phenotype in the Fbn1 mice carrying a corresponding variant of FBN1 in the hybrid1 domain that was identified in a patient with familial aortic dissection.

Regulatory Role of eIF2αK4 in Amino Acid Transporter Expression in Mouse Brain Capillary Endothelial Cells.

Purpose: Amino acid transporters are expressed in the brain capillary endothelial cells that form the blood-brain barrier (BBB), and their expression levels change during the neonatal period. This study aimed to investigate the molecular mechanisms regulating amino acid transporter levels in mouse brain capillary endothelial cells.

Methods: Capillaries were isolated from the brains of neonatal and adult mice.

Progressive Amyloid-β Accumulation in the Brain leads to Altered Protein Expressions in the Liver and Kidneys of APP knock-in Mice.

Impaired hepatic and renal function influence Alzheimer's disease (AD) progression; however, whether AD progression affects these important organ functions remains unclear. Here, we investigated the impact of AD progression, characterized by brain amyloid-beta (Aβ) accumulation, on liver and kidney function of App (APP-KI) mice using quantitative proteomics. SWATH-based quantitative proteomics revealed changes in mitochondrial, drug metabolism, and pharmacokinetic-related proteins in mouse liver and kidneys during the early (2-month-old) and intermediate (5-month-old) stages of Aβ accumulation.

Insulin receptor at the blood-brain barrier: Transport and signaling.

The blood-brain barrier (BBB) is a unique system of the brain microvasculature that limits the exchange between the blood and the brain. Brain microvascular endothelial cells form the BBB as part of the neurovascular unit and express insulin receptors. The insulin receptor at the BBB has been studied in two different functional aspects.

PREX1 improves homeostatic proliferation to maintain a naive CD4+ T cell compartment in older age.

The human adult immune system maintains normal T cell counts and compensates for T cell loss throughout life, mainly through peripheral homeostatic proliferation after the ability of the thymus to generate new T cells has rapidly declined at adolescence. This process is mainly driven by STAT5-activating cytokines, most importantly IL-7, and is very effective in maintaining a large naive CD4+ T cell compartment into older age. Here, we describe that naive CD4+ T cells undergo adaptations to optimize IL-7 responses by upregulating the guanine-nucleotide exchange factor PREX1 in older age.

Bakuchiol targets mitochondrial proteins, prohibitins and voltage-dependent anion channels: New insights into developing antiviral agents.

We previously reported that bakuchiol, a phenolic isoprenoid anticancer compound, and its analogs exert anti-influenza activity. However, the proteins targeted by bakuchiol remain unclear. Here, we investigated the chemical structures responsible for the anti-influenza activity of bakuchiol and found that all functional groups and C6 chirality of bakuchiol were required for its anti-influenza activity.

Proteomic alterations in the brain and blood-brain barrier during brain Aβ accumulation in an APP knock-in mouse model of Alzheimer's disease.

Background: Blood-brain barrier (BBB) dysfunction is supposed to be an early event in the development of Alzheimer's disease (AD). This study aimed to investigate the relationship between BBB alterations and AD progression in terms of amyloid-β peptide (Aβ) accumulation in the brains of humanized amyloid precursor protein knock-in (APP-KI) mice.

Methods: Brain Aβ accumulation was examined using immunohistochemical analysis.

Development and Functional Evaluation of MDR1-expressing Microvascular Endothelial-like Cells Derived from Human iPS Cells as an In vitro Blood-brain Barrier Model.

In order to establish an in vitro model of the human blood-brain barrier (BBB), MDR1-overexpressing human induced pluripotent stem cells (hiPSCs) were generated, and they were differentiated to MDR1-expressing brain microvascular endothelial-like cells (MDR1-expressing hiPS-BMECs). MDR1-expressing hiPS-BMECs monolayers showed good barrier function in terms of tight junction protein expression and trans-epithelial electrical resistance (TEER). In sequential window acquisition of all theoretical fragment ion spectra mass spectrometry (SWATH-MS), MDR1 protein expression was markedly increased in MDR1-expressing hiPS-BMECs, whereas other ABC and SLC transporters showed almost identical expression between MDR1-expressing hiPS-BMECs and mock hiPS-BMECs, suggesting that MDR1 overexpression had little or no knock-on effect on other proteins.

G protein-biased LPAR1 agonism of prototypic antidepressants: Implication in the identification of novel therapeutic target for depression.

Prototypic antidepressants, such as tricyclic/tetracyclic antidepressants (TCAs), have multiple pharmacological properties and have been considered to be more effective than newer antidepressants, such as selective serotonin reuptake inhibitors, in treating severe depression. However, the clinical contribution of non-monoaminergic effects of TCAs remains elusive. In this study, we discovered that amitriptyline, a typical TCA, directly binds to the lysophosphatidic acid receptor 1 (LPAR1), a G protein-coupled receptor, and activates downstream G protein signaling, while exerting a little effect on β-arrestin recruitment.

Stem-like CD4 T cells in perivascular tertiary lymphoid structures sustain autoimmune vasculitis.

Autoimmune vasculitis of the medium and large elastic arteries can cause blindness, stroke, aortic arch syndrome, and aortic aneurysm. The disease is often refractory to immunosuppressive therapy and progresses over decades as smoldering aortitis. How the granulomatous infiltrates in the vessel wall are maintained and how tissue-infiltrating T cells and macrophages are replenished are unknown.

SETD1A function in leukemia is mediated through interaction with mitotic regulators BuGZ/BUB3.

The H3K4 methyltransferase SETD1A plays a crucial role in leukemia cell survival through its noncatalytic FLOS domain-mediated recruitment of cyclin K and regulation of DNA damage response genes. In this study, we identify a functional nuclear localization signal in and interaction partners of the FLOS domain. Our screen for FLOS domain-binding partners reveals that the SETD1A FLOS domain binds mitosis-associated proteins BuGZ/BUB3.

Logistics and distribution of small extracellular vesicles from the subcutaneous space to the lymphatic system.

Small extracellular vesicles (sEVs) are small, cell-derived particles with sizes of approximately 100 nm. Since these particles include cargos such as host cell-derived proteins, messenger RNAs, and micro RNAs, they serve as mediators of cell-cell communication. While the analysis of the pharmacokinetic of sEVs after the intravenous injection have been reported, the lymphatic transport of sEVs remains unclear.

Development of a method for isolating brain capillaries from a single neonatal mouse brain and comparison of proteomic profiles between neonatal and adult brain capillaries.

Background: The functions and protein expressions of the blood-brain barrier are changed throughout brain development following birth. This study aimed to develop a method to isolate brain capillaries from a single frozen neonatal mouse brain and elucidate the enrichment of brain capillaries by quantitative proteomic analysis. We further compared the expression profile of proteins between neonatal and adult brain capillary fractions.

Effect of antibiotic-administration period on hepatic bile acid profile and expression of pharmacokinetic-related proteins in mouse liver, kidney, and brain capillaries.

Antibiotic administration affects pharmacokinetics through changes in the intestinal microbiota, and bile acids are involved in this regulation. The purpose of the present study was to clarify the effect of different periods of antibiotic administration on the hepatic bile acid profile and expression of pharmacokinetic-related proteins in mouse liver, kidney, and brain capillaries. Vancomycin and polymyxin B were orally administered to mice for either 5- or 25-days.

Deficiency of the CD155-CD96 immune checkpoint controls IL-9 production in giant cell arteritis.

Loss of function of inhibitory immune checkpoints, unleashing pathogenic immune responses, is a potential risk factor for autoimmune disease. Here, we report that patients with the autoimmune vasculitis giant cell arteritis (GCA) have a defective CD155-CD96 immune checkpoint. Macrophages from patients with GCA retain the checkpoint ligand CD155 in the endoplasmic reticulum (ER) and fail to bring it to the cell surface.

Hyperactivity of the CD155 immune checkpoint suppresses anti-viral immunity in patients with coronary artery disease.

Pre-existent cardiovascular disease is a risk factor for weak anti-viral immunity, but underlying mechanisms remain undefined. Here, we report that patients with coronary artery disease (CAD) have macrophages (Mϕ) that actively suppress the induction of helper T cells reactive to two viral antigens: the SARS-CoV2 Spike protein and the Epstein-Barr virus (EBV) glycoprotein 350. CAD Mϕ overexpressed the methyltransferase METTL3, promoting the accumulation of N⁶-methyladenosine (m6A) in Poliovirus receptor (CD155) mRNA.

Aging-associated HELIOS deficiency in naive CD4 T cells alters chromatin remodeling and promotes effector cell responses.

Immune aging combines cellular defects in adaptive immunity with the activation of pathways causing a low-inflammatory state. Here we examined the influence of age on the kinetic changes in the epigenomic and transcriptional landscape induced by T cell receptor (TCR) stimulation in naive CD4 T cells. Despite attenuated TCR signaling in older adults, TCR activation accelerated remodeling of the epigenome and induced transcription factor networks favoring effector cell differentiation.

SETD1A regulates transcriptional pause release of heme biosynthesis genes in leukemia.

Histone methyltransferase SETD1A is critical for acute myeloid leukemia (AML) cell survival, but the molecular mechanism driving SETD1A gene regulation remains elusive. To delineate the role of SETD1A, we utilize a protein degrader technology to induce rapid SETD1A degradation in AML cell lines. SETD1A degradation results in immediate downregulation of transcripts associated with DNA repair and heme biosynthesis pathways.

Human Hepatic Transporter Signature Peptides for Quantitative Targeted Absolute Proteomics: Selection, Digestion Efficiency, and Peptide Stability.

Purpose: Quantitative targeted absolute proteomics (QTAP) quantifies proteins by measuring the signature peptides produced from target proteins by trypsin digestion. The selection of signature peptides is critical for reliable peptide quantification. The purpose of this study was to comprehensively assess the digestion efficiency and stability of tryptic peptides and to identify optimal signature peptides for human hepatic transporters and membrane marker proteins.