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Objective: To establish a mesenchymal stem cell（MSC）-based in vitro cell model for the evaluation of mouse bone marrow acute graft-versus-host disease (aGVHD)., Methods: Female C57BL/6N mice aged 6-8 weeks were used as bone marrow and lymphocyte donors, and female BALB/c mice aged 6-8 weeks were used as aGVHD recipients. The recipient mouse received a lethal dose (8.0 Gy,72.76 cGy/min) of total body γ irradiation, and injected with donor mouse derived bone marrow cells (1×10 7 /mouse) in 6-8 hours post irradiation to establish a bone marrow transplantation (BMT) mouse model ( n =20). In addition, the recipient mice received a lethal dose (8.0 Gy,72.76 cGy/min) of total body γ irradiation, and injected with donor mouse derived bone marrow cells (1×10 7 /mouse) and spleen lymphocytes (2×10 6 /mouse) in 6-8 hours post irradiation to establish a mouse aGVHD model ( n =20). On the day 7 after modeling, the recipient mice were anesthetized and the blood was harvested post eyeball enucleation. The serum was collected by centrifugation. Mouse MSCs were isolated and cultured with the addition of 2%, 5%, and 10% recipient serum from BMT group or aGVHD group respectively. The colony-forming unit-fibroblast（CFU-F) experiment was performed to evaluate the potential effects of serums on the self-renewal ability of MSC. The expression of CD29 and CD105 of MSC was evaluated by immunofluorescence staining. In addition, the expression of self-renewal-related genes including Oct-4 , Sox-2 , and Nanog in MSC was detected by real-time fluorescence quantitative PCR（RT-qPCR)., Results: We successfully established an in vitro cell model that could mimic the bone marrow microenvironment damage of the mouse with aGVHD. CFU-F assay showed that, on day 7 after the culture, compared with the BMT group, MSC colony formation ability of aGVHD serum concentrations groups of 2% and 5% was significantly reduced （ P < 0．05）; after the culture, at day 14, compared with the BMT group, MSC colony formation ability in different aGVHD serum concentration was significantly reduced （ P < 0．05）. The immunofluorescence staining showed that, compared with the BMT group, the proportion of MSC surface molecules CD29 + and CD105 + cells was significantly dereased in the aGVHD serum concentration group ( P < 0.05), the most significant difference was at a serum concentration of 10% （ P < 0．001, P < 0.01）. The results of RT-qPCR detection showed that the expression of the MSC self-renewal-related genes Oct-4 , Sox-2 , and Nanog was decreased, the most significant difference was observed at an aGVHD serum concentration of 10% （ P < 0.01, P < 0．001, P < 0．001）., Conclusion: By co-culturing different concentrations of mouse aGVHD serum and mouse MSC, we found that the addition of mouse aGVHD serum at different concentrations impaired the MSC self-renewal ability, which providing a new tool for the field of aGVHD bone marrow microenvironment damage.

Skeletal stem cells (SSC) have gained attentions as candidates for the treatment of osteoarthritis due to their osteochondrogenic capacity. However, the immunomodulatory properties of SSC, especially under delivery operations, have been largely ignored. In the study, we found that Pdpn + and Grem1 + SSC subpopulations owned immunoregulatory potential, and the single-cell RNA sequencing (scRNA-seq) data suggested that the mechanical activation of microgel carriers on SSC induced the generation of Pdpn + Grem1 + Ptgs2 + SSC subpopulation, which was potent at suppressing macrophage inflammation. The microgel carriers promoted the YAP nuclear translocation, and the activated YAP protein was necessary for the increased expression of Ptgs2 and PGE 2 in microgels-delivered SSC, which further suppressed the expression of TNF-ɑ, IL-1β and promoted the expression of IL-10 in macrophages. SSC delivered with microgels yielded better preventive effects on articular lesions and macrophage activation in osteoarthritic rats than SSC without microgels. Chemically blocking the YAP and Ptgs2 in microgels-delivered SSC partially abolished the enhanced protection on articular tissues and suppression on osteoarthritic macrophages. Moreover, microgel carriers significantly prolonged SSC retention time in vivo without increasing SSC implanting into osteoarthritic joints. Together, our study demonstrated that microgel carriers enhanced SSC reprogramming towards immunomodulatory phenotype to regulate macrophage phenotype transformation for effectively osteoarthritic therapy by promoting YAP protein translocation into nucleus. The study not only complement and perfect the immunological mechanisms of SSC-based therapy at the single-cell level, but also provide new insight for microgel carriers in stem cell-based therapy., (© 2023 The Authors.)

Objective: To establish an intestinal organoid model that mimic acute graft versus host disease (aGVHD) caused intestinal injuries by using aGVHD murine model serum and organoid culture system, and explore the changes of aGVHD intestine in vitro by advantage of organoid technology., Methods: 20-22 g female C57BL/6 mice and 20-22 g female BALB/c mice were used as donors and recipients for bone marrow transplantation, respectively. Within 4-6 h after receiving a lethal dose (8.0 Gy) of γ ray total body irradiation, a total of 0.25 ml of murine derived bone marrow cells (1×10 7 /mice, n =20) and spleen nucleated cells (5×10 6 /mice, n =20) was infused to establish a mouse model of aGVHD ( n =20). The aGVHD mice were anesthetized at the 7th day after transplantation, and the veinal blood was harvested by removing the eyeballs, and the serum was collected by centrifugation. The small intestinal crypts of healthy C57BL/6 mice were harvested and cultivated in 3D culture system that maintaining the growth and proliferation of intestinal stem cells in vitro. In our experiment, 5%, 10%, 20% proportions of aGVHD serum were respectively added into the organoid culture system for 3 days. The formation of small intestinal organoids were observed under an inverted microscope and the morphological characteristics of intestinal organoids in each groups were analyzed. For further evaluation, the aGVHD intestinal organoids were harvested and their pathological changes were observed. Combined with HE staining, intestinal organ morphology evaluation was performed. Combined with Alcian Blue staining, the secretion function of aGVHD intestinal organoids was observed. The distribution and changes of Lgr5 + and Clu + intestinal stem cells in intestinal organoids were analyzed under the conditions of 5%, 10% and 20% serum concentrations by immunohistochemical stainings., Results: The results of HE staining showed that the integrity of intestinal organoids in the 5% concentration serum group was better than that in the 10% and 20% groups. The 5% concentration serum group showed the highest number of organoids, the highest germination rate and the lowest pathological score among experimental groups, while the 20% group exhibited severe morphological destruction and almost no germination was observed, and the pathological score was the highest among all groups( t =3.668, 4.334,5.309, P <0.05). The results of Alican blue staining showed that the secretion function of intestinal organoids in serum culture of aGVHD in the 20% group was weaker than that of the 5% group and 10% of the organoids, and there was almost no goblet cells, and mucus was stainned in the 20% aGVHD serum group. The immunohistochemical results showed that the number of Lgr5 + cells of intestinal organoids in the 5% group was more than that of the intestinal organoids in the 10% aGVHD serum group and 20% aGVHD serum group. Almost no Clu + cells were observed in the 5% group. The Lgr5 + cells in the 20% group were seriously injuried and can not be observed. The proportion of Clu + cells in the 20% group significantly increased., Conclusion: The concentration of aGVHD serum in the culture system can affect the number and secretion function of intestinal organoids as well as the number of intestinal stem cells in organoids. The higher the serum concentration, the greater the risk of organoid injury, which reveal the characteristics of the formation and functional change of aGVHD intestinal organoids, and provide a novel tool for the study of intestinal injury in aGVHD.

Hematopoietic stem cell transplantation (HSCT) is one of the effective options for the treatment of irradiation-induced injury on hematopoiesis, malignant hematological diseases, and numerous benign severe hematopathy. However, the cellular composition of the graft for HSCT, as well as the significant events of transplanted HSCs in receipients including HSC homing, engraftment, differentiation, remains to be further elucidated. In recent years, with advances in single-cell techniques, the hematopoiesis has been decoding at single cell scale. In addition, single-cell RNA sequencing (scRNA-seq) has been used in the evaluation of hematopoietic dynamics post HSCT, which may be helpful to improve HSCT protocols and clinical outcomes. Hence, the recent advances of evaluating HSCT at single cell scale and the directions worthy paying attention to in the field have been reviewed briefly.

Mesenchymal stem cells (MSC) are capable of supporting hematopoiesis, regulating immune responses, promoting tissue regeneration and homing to damaged tissues, but their efficacy cannot completely exploit due to various factors. Studies in recent years have shown that the biological characteristics of mesenchymal stem cells have plasticity. Researchers can enhance the biological performance of MSC by pretreatment with hypoxia, bioactive molecules, genetic modification, and mechanical stimulation, as well as adjusting MSC transplantation strategies, which has great significance for promoting the transformation of MSC. Therefore, in this review, the recent research advances in the plasticity of the biological characteristics of MSC are summarized briefly.

Objectives Medical knowledge extraction (MKE) plays a key role in natural language processing (NLP) research in electronic medical records (EMR), which are the important digital carriers for recording medical activities of patients. Named entity recognition (NER) and medical relation extraction (MRE) are two basic tasks of MKE. This study aims to improve the recognition accuracy of these two tasks by exploring deep learning methods. Methods This study discussed and built two application scenes of bidirectional long short-term memory combined conditional random field (BiLSTM-CRF) model for NER and MRE tasks. In the data preprocessing of both tasks, a GloVe word embedding model was used to vectorize words. In the NER task, a sequence labeling strategy was used to classify each word tag by the joint probability distribution through the CRF layer. In the MRE task, the medical entity relation category was predicted by transforming the classification problem of a single entity into a sequence classification problem and linking the feature combinations between entities also through the CRF layer. Results Through the validation on the I2B2 2010 public dataset, the BiLSTM-CRF models built in this study got much better results than the baseline methods in the two tasks, where the F1-measure was up to 0.88 in NER task and 0.78 in MRE task. Moreover, the model converged faster and avoided problems such as overfitting. Conclusion This study proved the good performance of deep learning on medical knowledge extraction. It also verified the feasibility of the BiLSTM-CRF model in different application scenarios, laying the foundation for the subsequent work in the EMR field.

Objective: To explore the relations between fasting blood glucose (FBG), glycosylated hemoglobin A1c (HbA1c) and glycosylated serum protein (GSP)., Methods: FBG, HbA1c and GSP were measured in 303 patients with diabetic nephropathy and in 167 non-diabetic patients with comparable baseline data, and the correlations between FBG, HbA1c and GSP were analyzed., Results: GSP levels were significantly higher in patients with diabetic nephropathy than in the non-diabetic patients (P<0.01). In patients with diabetic nephropathy, GSP levels were found to positively correlate to FBG (r=0.606) and HbA1c (r=0.733)., Conclusion: Patients with diabetic nephropathy show strong correlations between FBG, HbA1c and GSP. GSP detection is convenient, stable, and practical in evaluating the average FBG over a short term, which reduces the interference by FBG fluctuations in conventional blood glucose monitoring.

Cytokines and beta-chemokines are important mediators of the immune system and are expressed in many infectious diseases. To study cytokine and beta-chemokine profiles during pathogenesis of lentiviral infection and progression to AIDS in rhesus macaques, we established new quantitative real-time reverse transcriptase-polymerase chain reaction (RT-PCR) assays based on TaqMan chemistry. Using synthetic RNA standards, we quantified mRNAs of IL-2, IL-4, IL-6, IL-10, IL-12 p40, interferon gamma (IFN-gamma), tumor necrosis factor alpha (TNF-alpha), RANTES, macrophage inflammatory protein 1 alpha (MIP-1 alpha), and MIP-1 beta in unstimulated peripheral blood mononuclear cells (PBMCs) and lymph nodes from macaques chronically infected with SIV or SHIV. Viremic monkeys with decreased CD4(+) T cell counts (<500 cells/microl) had significantly higher IL-10 mRNA expression than uninfected controls, which parallels the findings in HIV-1-infected humans. In addition, MIP-1 alpha, MIP-1 beta, and RANTES mRNA expression increased in viremic monkeys with decreased CD4(+) T cell counts; gene expression was inversely correlated with CD4(+) T cell counts, but not viral load. The newly established quantitative real-time RT-PCR assays will allow the determination of cytokine and beta-chemokine patterns in rhesus macaques in studies of microbial pathogenesis or vaccine development.