Pontocerebellar hypoplasia (PCH) is a group of neurological disorders that affect the development of the brain, in particular, the pons and cerebellum. Homozygous mutations of TBC1D23 have been found recently to lead to PCH; however, the underlying molecular mechanisms remain unclear. Here, we show that the crystal structure of the TBC1D23 C-terminal domain adopts a Pleckstrin homology domain fold and selectively binds to phosphoinositides, in particular, PtdIns(4)P, through one surface while binding FAM21 via the opposite surface. Mutation of key residues of TBC1D23 or FAM21 selectively disrupts the endosomal vesicular trafficking toward the Trans-Golgi Network. Finally, using the zebrafish model, we show that PCH patient-derived mutants, impacting either phosphoinositide binding or FAM21 binding, lead to abnormal neuronal growth and brain development. Taken together, our data provide a molecular basis for the interaction between TBC1D23 and FAM21, and suggest a plausible role for PtdIns(4)P in the TBC1D23-mediating endosome-to-TGN trafficking pathway. Defects in this trafficking pathway are, at least partially, responsible for the pathogenesis of certain types of PCH.

Systemic inflammatory responses can severely injure lungs, prompting efforts to explore how to attenuate such injury. Here we explored whether platelets can help attenuate lung injury in mice resulting from extracorporeal circulation (ECC)-induced systemic inflammatory responses. Mice were subjected to ECC for 30 min, then treated with phosphate-buffered saline, platelets, the GPIIb/IIIa inhibitor Tirofiban, or the combination of platelets and Tirofiban. Blood and lung tissues were harvested 60 min later, and lung injury and inflammatory status were assessed. As expected, ECC caused systemic inflammation and pulmonary dysfunction, and platelet transfusion resulted in significantly milder lung injury and higher lung function. It also led to greater numbers of circulating platelet-leukocyte aggregates and greater platelet accumulation in the lung. Platelet transfusion was associated with higher production of transforming growth factor-β and as well as lower levels of tumour necrosis factor-α and neutrophil elastase in plasma and lung. None of these platelet effects was observed in the presence of Tirofiban. Our results suggest that, at least under certain conditions, platelets can protect lung from injury induced by systemic inflammatory responses.

Adipose-derived stem cells (ASCs) have been defined as cells that undergo sustained in vitro growth and have multilineage differentiation potential. However, the identity and purification of ASCs has proved elusive due to the lack of specific markers and poor understanding of their physiological roles. Here, we prospectively isolated and identified a restricted homogeneous subpopulation of ASCs (Lin(-)CD271(+)Sca-1(+)) from mouse adipose tissues on the basis of cell-surface markers. Individual ASCs generated colony-forming unit-fibroblast at a high frequency and could differentiate into adipocytes, osteoblasts, and chondrocytes in vitro. Expansion of ASCs in a large quantity was feasible in medium supplemented with fibroblast growth factor-2 and leukemia inhibitory factor, without loss of adipogenic and osteogenic differentiation capacity. Moreover, we found that the transplanted ASCs can differentiate into adipocytes in adipogenic microenvironment in vivo and osteoblasts in osteogenic microenvironment in vivo. Thus we proved that Lin, CD271, and Sca-1 could be used as the specific markers to purify ASCs from adipose tissue. The method we established to identify ASCs as defined in vivo entities will help develop ASCs transplantation as a new therapeutic strategy for bone regeneration and adipose tissue regeneration in clinic.

The use of stem cells combined with gene therapy could be an important way to facilitate bone regeneration. In this study, the aim was to investigate the potential of growth and differentiation factor-5 (GDF5) to genetically manipulate human mesenchymal stem cells (hMSCs) for bone regeneration. Recombinant adenovirus Ad-GDF5 and Ad-GFP were constructed and identified, and the titer of both were determined. Third-passage hMSCs were infected with adenovirus, and the expression of GDF5 was confirmed by detection of GFP-positive cells, GDF5 mRNA levels, Western blotting, and enzyme-linked immunosorbent assay (ELISA). hMSCs at passage 3 were divided into four groups: (1) an experimental group infected with Ad-GDF5, (2) a positive control group cultured with osteogenic differentiation medium, (3) a control group infected with Ad-GFP cultured with standard medium, and (4) a blank control group cultured with standard medium. Evaluation of cell morphology and proliferation, analysis of the expression of genes related to osteogenic differentiation, von Kossa staining, and immunofluorescent staining of collagen I were used to investigate the osteogenesis of cells among the groups. After culturing the cells for 2 days under each corresponding condition, the cells were detached and subcutaneously injected into the backs of nude mice to evaluate bone formation. Samples were collected for histological staining, protein Western blotting, and micro-computer tomography. When infected with Ad-GDF5, hMSCs could overexpress GDF5 for a prolonged period in vitro and reach a concentration of 160 ng/ml. Cells infected with Ad-GDF5 or cultured in osteogenic medium displayed osteogenic differentiation based on their histological and cellular properties and on their gene and protein expression patterns. Furthermore, Ad-GDF5 showed a better ability to upregulate the expression of collagen I, alkaline phosphatase, and osteocalcin mRNA than the osteogenic medium. Furthermore, Ad-GDF5 expression was associated with enhanced bone formation in vivo. Our findings suggest that hMSCs infected with Ad-GDF5 can differentiate in an osteogenic direction and may be a promising cell source for bone regeneration.

Immunophenotype is critical for diagnosing common B-cell acute lymphoblastic leukemia (common ALL) and detecting minimal residual disease. We developed a protocol to explore the immunophenotypic profiles of common ALL based on the expression levels of the antigens associated with B lymphoid development, including IL-7Rα (CD127), cytoplasmic CD79a (cCD79a), CD19, VpreB (CD179a), and sIgm, which are successive and essential for progression of B cells along their developmental pathway. Analysis of the immunophenotypes of 48 common ALL cases showed that the immunophenotypic patterns were highly heterogeneous, with the leukemic cell population differing from case to case. Through the comprehensive analysis of immunophenotypic patterns, the profiles of patient-specific composite leukemia cell populations could provide detailed information helpful for the diagnosis, therapeutic monitoring, and individualized therapies for common ALL.

This study has investigated the growth-inhibitory and apoptosis-inducing effects of dihydrotanshinone, tanshinone I, tanshinone IIA, and cryptotanshinone on hematological malignancy cell lines, aiming to explore their structure-activity relationship. The growth-inhibitory effects of the tanshinones on K562 and Raji cells were assessed using a modified MTT assay; the apoptosis-inducing effects were assessed by fluorescence microscopy and flow cytometry analysis. The changes in cellular morphology were observed using an inverted phase-contrast microscope. MTT results revealed that these tanshinones inhibited cell proliferation in a concentration-dependent and time-dependent manner. The IC50 values of dihydrotanshinone, tanshinone I, tanshinone IIA, and cryptotanshinone for K562 cells were 3.50, 13.52, 19.32, and 47.52 μmol/l at 24 h; 1.36, 4.70, 5.67, and 22.72 μmol/l at 48 h; and 1.15, 1.59, 2.82, and 19.53 μmol/l at 72 h, and the values for Raji cells were 3.30, 4.37, 12.92, and 52.36 μmol/l at 24 h; 1.55, 1.71, 6.54, and 25.45 μmol/l at 48 h; and 1.07, 1.38, 1.89, and 18.47 μmol/l at 72 h. The flow cytometry analysis demonstrated that these tanshinones induced apoptosis of K562 cells in a concentration-dependent manner, and dihydrotanshinone as well as tanshinone I were more potent than tanshinone IIA and cryptotanshinone. Some noticeable apoptotic morphologies could be observed by fluorescence microscopy on tanshinones-treated Raji cells. Collectively, these tanshinones caused growth inhibition and apoptosis in hematological malignancy cell lines, with dihydrotanshinone being the most potent, followed by tanshinone I, tanshinone IIA, and cryptotanshinone. These results suggested that the structure of aromatic ring A enhanced the cytotoxicity and the structure of ring C may have contributed to the cytotoxicity, but the mechanisms need to be further investigated.

Fibroblasts and myofibroblasts are major mesenchymal cells in the lamina propria of colon mucosa and in colon cancer tissues. Detailed insight into the highly specific populations of fibroblasts and myofibroblasts is required to understand the integrity and homeostasis of human colon mucosa and colon cancer. Based on gene expression profiles of single cells, we identified fibroblast populations that produce extracellular matrix components, Wnt ligand- and BMP-secreting fibroblasts, chemokine- and chemokine ligand-generating fibroblasts, highly activated fibroblasts, immune-modulating fibroblasts, epithelial cell-modulating myofibroblasts, stimuli-responsive myofibroblasts, proliferating myofibroblasts, fibroblast-like myofibroblasts, matrix producing myofibroblasts, and contractile myofibroblasts in human colon mucosa. In colon cancer tissue, the compositions of fibroblasts and myofibroblasts were highly altered, as were the expressing patterns of genes including BMPs, Wnt ligands, chemokines, chemokine ligands, growth factors and extracellular matrix components in fibroblasts and myofibroblasts. Our work expands the working atlas of fibroblasts and myofibroblasts and provides a framework for interrogating the complexity of stromal cells in human healthy colon mucosa and colon cancer tissues.

Background:Intraoperative blood salvage (IBS) recovers most lost blood, and is widely used in the clinic. It is unclear why IBS does not reduce long-term postoperative requirements for red blood cells (RBCs), and 1 possibility is that IBS affects RBC lifespan.Methods:Prospectively enrolled patients who underwent spine, pelvic, or femur surgery not involving allogeneic RBC transfusion were grouped based on whether they received IBS or not. Volumes of blood lost and of RBCs salvaged during surgery were recorded. Total blood cell counts, levels of plasma-free hemoglobin, and CD235a-positive granulocytes were determined perioperatively.Results:Although intraoperative blood loss was higher in the IBS group (n = 45) than in the non-IBS group (n = 52) (P < .001), hemoglobin levels were similar between groups (P = .125) at the end of surgery. Hemoglobin levels increased in non-IBS patients (4 ± 11 g/L), but decreased in IBS patients (−7 ± 12 g/L) over the first 3 postoperative days. Nadir hemoglobin levels after surgery were higher in the non-IBS group (107 ± 12 g/L) than in the IBS group (91 ± 12 g/L). Salvaged RBC volume correlated with hemoglobin decrease (r = 0.422, P = .004). In multivariate analysis, salvaged RBC volume was an independent risk factor for hemoglobin decrease (adjusted odds ratio 1.002, 95% confidence interval 1.001–1.004, P = .008). Flow cytometry showed the numbers of CD235a-positive granulocytes after surgery to be higher in the IBS group than in the non-IBS group (P < .05).Conclusion:IBS may shorten the lifespan of RBCs by triggering their engulfment upon re-infusion (China Clinical Trial Registry ChiCTR-OCH-14005140).