Proteome Analysis of Serum Purified Using Solanum tuberosum and Lycopersicon esculentum Lectins.

Serum and plasma exhibit a broad dynamic range of protein concentrations, posing challenges for proteome analysis. Various technologies have been developed to reduce this complexity, including high-abundance depletion methods utilizing antibody columns, extracellular vesicle enrichment techniques, and trace protein enrichment using nanobead cocktails. Here, we employed lectins to address this, thereby extending the scope of biomarker discovery in serum or plasma using a novel approach. We enriched serum proteins using 37 different lectins and subjected them to LC-MS/MS analysis with data-independent acquisition. Solanum tuberosum lectin (STL) and Lycopersicon esculentum lectin (LEL) enabled the detection of more serum proteins than the other lectins. STL and LEL bind to N-acetylglucosamine oligomers, emphasizing the significance of capturing these oligomer-binding proteins when analyzing serum trace proteins. Combining STL and LEL proved more effective than using them separately, allowing us to identify over 3000 proteins from serum through single-shot proteome analysis. We applied the STL/LEL trace-protein enrichment method to the sera of systemic lupus erythematosus model mice. This revealed differences in >1300 proteins between the systemic lupus erythematosus model and control mouse sera, underscoring the utility of this method for biomarker discovery.

Acsbg1-dependent mitochondrial fitness is a metabolic checkpoint for tissue Treg cell homeostasis.

Regulatory T (Treg) cells are critical for immunological tolerance and immune homeostasis. Treg cells strongly rely on mitochondrial metabolism and show a lower level of glycolysis. However, little is known about the role of lipid metabolism in the regulation of Treg cell homeostasis. Some members of the ACSL family of acyl-coenzyme A (CoA) synthases are expressed in T cells, but their function remains unclear. A combination of RNA-sequencing and proteome analyses shows that Acsbg1, a member of ACSL, is selectively expressed in Treg cells. We show that the genetic deletion of Acsbg1 not only causes mitochondrial dysfunction, but it also dampens other metabolic pathways. The extrinsic supplementation of Acsbg1-deficient Treg cells with oleoyl-CoA restores the phenotype of the Treg metabolic signature. Furthermore, this pathway in ST2+ effector Treg cells enhances immunosuppressive capacity in airway inflammation. Thus, Acsbg1 serves as a metabolic checkpoint governing Treg cell homeostasis and the resolution of lung inflammation.

A highly efficient method for extracting peptides from a single mouse hypothalamus.

Living organisms contain a variety of endogenous peptides that function as significant regulators of many biological processes. Endogenous peptides are typically analyzed using liquid chromatography-mass spectrometry (LC-MS). However, due to the low efficiency of peptide extraction and low abundance of peptides in a single animal, LC-MS-based peptidomics studies have not facilitated an understanding of the individual differences and tissue specificity of peptide abundance. In this study, we developed a peptide extraction method followed by nano-flow LC-MS/MS analysis. This method enabled highly efficient and reproducible peptide extraction from sub-milligram quantities of hypothalamus dissected from a single animal. Diverse bioactive and authentic peptides were detected from a sample volume equivalent to 135 µg of hypothalamus. This method may be useful for elucidating individual differences and tissue specificity, as well as for facilitating the discovery of novel bioactive peptides and biomarkers and developing peptide therapeutics.

Hyperthermia in the treatment of recurrent abdominal desmoid tumor.

The most suitable management of recurrent abdominal desmoid tumor is still unclear. A case of recurrent huge abdominal desmoid tumor successfully treated by hyperthermia therapy is described. A 63-year-old man was operated upon for desmoid tumor in the retroperitoneum involving pancreas, posterior wall of the stomach and transverse mesocolon in 2007. In 2008, the tumor recurred and could not be resected because of the patient refused the operation. Several therapies using tamoxifen, anastrozole, imatinib mesylate and radiotherapy were all ineffective. The tumor grew bigger and bigger during a treatment period. Finally, hyperthermia treatment was applied to the tumor. The size of the recurrent desmoid tumor reduced 75% by hyperthermia treatment for 46-month. Base on this experience, we recommend hyperthermia as the treatment for patients with recurrent abdominal desmoid tumor that several therapeutic strategies did not achieve a remarkable response.

Proteomic study of sera from patients with bladder cancer: usefulness of S100A8 and S100A9 proteins.

To effectively obtain tumour-specific markers, fractionated proteins obtained using reversed-phase high-performance liquid chromatography for patient-matched pre- and postoperative sera from bladder cancer patients were compared by two-dimensional gel electrophoresis. The usefulness of the identified proteins was confirmed immunohistochemically. S100A8 and S100A9 were identified as tumour-associated proteins. The increased immunoreactive expression of S100A8 protein was associated with bladder wall muscle invasion of the tumour and cancer-specific survival (p<0.05), and the increased immunoreactive expression of S100A9 protein was associated with the tumour grade (p<0.05). In addition, increased expressions of both proteins was associated with recurrence-free survival at a median follow-up of 32.9 months (both p<0.05). On multivariate analysis, the expression of S100A8 was a significant predictor of recurrence (p<0.05). These findings may help to identify biologically aggressive tumors and, thus, patients who might benefit from more intensive adjuvant therapy.