Hematopoietic stem cells (HSCs) possess unique abilities such as self-renewal and differentiation to generate their progeny throughout life. HSCs have been shown to reside in a specifi c microenvironment called “HSC niche” in the bone marrow, and various types of cells have been identifi ed as HSC niche components. Among them, a perivascular area in the bone marrow has been paid much attention as a microenvironment regulating HSCs. Recent studies revealed that both endothelial cells and perivascular stromal cells contribute to HSC maintenance or quiescence. In this review, we provide an overview of recent studies uncovering the HSC niche function and focus on the roles of niche cells in the perivascular area.

For post-translational protein modifications such as phosphorylation, the involved residues have been recently identified by mass spectrometers. However, it is not easy to efficiently detect the therapeutic target from the vast amount of proteomic data. Neuronal growth cones are specialized, highly motile structures formed at the tip of axons, that are indispensable for synaptogenesis in the developing brain and for neuronal plasticity in the adult brain. However, there is lack of information on the molecular basis of growth cones in the mammalian brain. We performed a phosphoproteomic analysis of growth cone membrane fractions (2 mg) isolated from the rat forebrain on postnatal day 1. We chose the more abundant peptides as research-targets, based on the hypothesis that abundant phosphorylated sites are involved in important biological functions. The phosphopeptides detected with high frequency at the 1st (Serine [S] 96) and 9th (Threonine [T] 172) positions were the phosphorylation sites of neuronal growth-associated protein - 43 kDa (GAP 43). C-jun N-terminal kinase (JNK) was responsible for phosphorylation at these sites, which increased during neuronal development and axonal regeneration. T172 phosphorylation was also confi rmed in rodents and primates. This review introduces our methodology for fi nding novel phospho-proteins as therapeutic molecular targets for specifi c diseases, along with their regulatory kinases. We believe that our serial approach, as illustrated here, can be applied to various research fi elds. In future research, we propose to demonstrate that pT172 antibody can be utilized as an axonal growth and regeneration marker in humans.

Flow cytometry is a measuring device frequently used in basic research, in our facility, we have developed a fully automatic fl ow cytometer device that performs cell isolation, staining of cell nuclei, and measurement, and is using it for intraoperative diagnosis. Placing a small specimen in a reagent containing PI calculates, the total number of cells, the DNA histogram, and the Malignancy Index (MI), which means in the proliferation phase, the ratio of the number of cells (S, G2, M) / total number of cells. High MI reveals the appearance of DNA aneuploidy and an increase in cells in the proliferative phase. The major feature of this device is that calculating takes only within 10minutes by specializing in DNA amount analysis and thoroughly reviewing the process. Therefore, we can evaluate the malignancy of tumors in a short time. This report introduces our previous study of this device, stump diagnosis, WHO grading, prognosis in glioma, and differentiation from primary central nervous system lymphoma, then how to use it in decision making in the operation. Intraoperative flow cytometry has enabled various intraoperative decision-making support by converting rapid intraoperative diagnosis, which was an analog-like transmission, into digitized histological information. In the future, the development of this research makes expectations for more accurate diagnosis and prediction by artifi cial intelligence and the development of other departments.